diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2020-10-20 08:14:25 -0400 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-10-20 08:14:25 -0400 |
| commit | 1b21c8db0e3b71523ada0cf568372ebfcf0d3466 (patch) | |
| tree | 70e537fadc469c5fddabbdf116ea6090baaf4cf8 /arch/arm64 | |
| parent | 628ade2d0816b2675ab61ba6aadfc9a94e3e1589 (diff) | |
| parent | 4e5dc64c43192b4fd4c96ac150a8f013065f5f5b (diff) | |
Merge tag 'kvmarm-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into HEAD
KVM/arm64 updates for Linux 5.10
- New page table code for both hypervisor and guest stage-2
- Introduction of a new EL2-private host context
- Allow EL2 to have its own private per-CPU variables
- Support of PMU event filtering
- Complete rework of the Spectre mitigation
Diffstat (limited to 'arch/arm64')
61 files changed, 3417 insertions, 3420 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 6d232837cbee..51259274a819 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1165,32 +1165,6 @@ config UNMAP_KERNEL_AT_EL0 If unsure, say Y. -config HARDEN_BRANCH_PREDICTOR - bool "Harden the branch predictor against aliasing attacks" if EXPERT - default y - help - Speculation attacks against some high-performance processors rely on - being able to manipulate the branch predictor for a victim context by - executing aliasing branches in the attacker context. Such attacks - can be partially mitigated against by clearing internal branch - predictor state and limiting the prediction logic in some situations. - - This config option will take CPU-specific actions to harden the - branch predictor against aliasing attacks and may rely on specific - instruction sequences or control bits being set by the system - firmware. - - If unsure, say Y. - -config ARM64_SSBD - bool "Speculative Store Bypass Disable" if EXPERT - default y - help - This enables mitigation of the bypassing of previous stores - by speculative loads. - - If unsure, say Y. - config RODATA_FULL_DEFAULT_ENABLED bool "Apply r/o permissions of VM areas also to their linear aliases" default y diff --git a/arch/arm64/include/asm/assembler.h b/arch/arm64/include/asm/assembler.h index 54d181177656..ddbe6bf00e33 100644 --- a/arch/arm64/include/asm/assembler.h +++ b/arch/arm64/include/asm/assembler.h @@ -219,6 +219,23 @@ lr .req x30 // link register .endm /* + * @dst: destination register + */ +#if defined(__KVM_NVHE_HYPERVISOR__) || defined(__KVM_VHE_HYPERVISOR__) + .macro this_cpu_offset, dst + mrs \dst, tpidr_el2 + .endm +#else + .macro this_cpu_offset, dst +alternative_if_not ARM64_HAS_VIRT_HOST_EXTN + mrs \dst, tpidr_el1 +alternative_else + mrs \dst, tpidr_el2 +alternative_endif + .endm +#endif + + /* * @dst: Result of per_cpu(sym, smp_processor_id()) (can be SP) * @sym: The name of the per-cpu variable * @tmp: scratch register @@ -226,11 +243,7 @@ lr .req x30 // link register .macro adr_this_cpu, dst, sym, tmp adrp \tmp, \sym add \dst, \tmp, #:lo12:\sym -alternative_if_not ARM64_HAS_VIRT_HOST_EXTN - mrs \tmp, tpidr_el1 -alternative_else - mrs \tmp, tpidr_el2 -alternative_endif + this_cpu_offset \tmp add \dst, \dst, \tmp .endm @@ -241,11 +254,7 @@ alternative_endif */ .macro ldr_this_cpu dst, sym, tmp adr_l \dst, \sym -alternative_if_not ARM64_HAS_VIRT_HOST_EXTN - mrs \tmp, tpidr_el1 -alternative_else - mrs \tmp, tpidr_el2 -alternative_endif + this_cpu_offset \tmp ldr \dst, [\dst, \tmp] .endm diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index 07b643a70710..c4ac9a13ad5f 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -31,13 +31,13 @@ #define ARM64_HAS_DCPOP 21 #define ARM64_SVE 22 #define ARM64_UNMAP_KERNEL_AT_EL0 23 -#define ARM64_HARDEN_BRANCH_PREDICTOR 24 +#define ARM64_SPECTRE_V2 24 #define ARM64_HAS_RAS_EXTN 25 #define ARM64_WORKAROUND_843419 26 #define ARM64_HAS_CACHE_IDC 27 #define ARM64_HAS_CACHE_DIC 28 #define ARM64_HW_DBM 29 -#define ARM64_SSBD 30 +#define ARM64_SPECTRE_V4 30 #define ARM64_MISMATCHED_CACHE_TYPE 31 #define ARM64_HAS_STAGE2_FWB 32 #define ARM64_HAS_CRC32 33 diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 89b4f0142c28..fba6700b457b 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -698,30 +698,6 @@ static inline bool system_supports_tlb_range(void) cpus_have_const_cap(ARM64_HAS_TLB_RANGE); } -#define ARM64_BP_HARDEN_UNKNOWN -1 -#define ARM64_BP_HARDEN_WA_NEEDED 0 -#define ARM64_BP_HARDEN_NOT_REQUIRED 1 - -int get_spectre_v2_workaround_state(void); - -#define ARM64_SSBD_UNKNOWN -1 -#define ARM64_SSBD_FORCE_DISABLE 0 -#define ARM64_SSBD_KERNEL 1 -#define ARM64_SSBD_FORCE_ENABLE 2 -#define ARM64_SSBD_MITIGATED 3 - -static inline int arm64_get_ssbd_state(void) -{ -#ifdef CONFIG_ARM64_SSBD - extern int ssbd_state; - return ssbd_state; -#else - return ARM64_SSBD_UNKNOWN; -#endif -} - -void arm64_set_ssbd_mitigation(bool state); - extern int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt); static inline u32 id_aa64mmfr0_parange_to_phys_shift(int parange) diff --git a/arch/arm64/include/asm/hyp_image.h b/arch/arm64/include/asm/hyp_image.h new file mode 100644 index 000000000000..daa1a1da539e --- /dev/null +++ b/arch/arm64/include/asm/hyp_image.h @@ -0,0 +1,36 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020 Google LLC. + * Written by David Brazdil <dbrazdil@google.com> + */ + +#ifndef __ARM64_HYP_IMAGE_H__ +#define __ARM64_HYP_IMAGE_H__ + +/* + * KVM nVHE code has its own symbol namespace prefixed with __kvm_nvhe_, + * to separate it from the kernel proper. + */ +#define kvm_nvhe_sym(sym) __kvm_nvhe_##sym + +#ifdef LINKER_SCRIPT + +/* + * KVM nVHE ELF section names are prefixed with .hyp, to separate them + * from the kernel proper. + */ +#define HYP_SECTION_NAME(NAME) .hyp##NAME + +/* Defines an ELF hyp section from input section @NAME and its subsections. */ +#define HYP_SECTION(NAME) \ + HYP_SECTION_NAME(NAME) : { *(NAME NAME##.*) } + +/* + * Defines a linker script alias of a kernel-proper symbol referenced by + * KVM nVHE hyp code. + */ +#define KVM_NVHE_ALIAS(sym) kvm_nvhe_sym(sym) = sym; + +#endif /* LINKER_SCRIPT */ + +#endif /* __ARM64_HYP_IMAGE_H__ */ diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h index 6f98fbd0ac81..54387ccd1ab2 100644 --- a/arch/arm64/include/asm/kvm_asm.h +++ b/arch/arm64/include/asm/kvm_asm.h @@ -7,11 +7,9 @@ #ifndef __ARM_KVM_ASM_H__ #define __ARM_KVM_ASM_H__ +#include <asm/hyp_image.h> #include <asm/virt.h> -#define VCPU_WORKAROUND_2_FLAG_SHIFT 0 -#define VCPU_WORKAROUND_2_FLAG (_AC(1, UL) << VCPU_WORKAROUND_2_FLAG_SHIFT) - #define ARM_EXIT_WITH_SERROR_BIT 31 #define ARM_EXCEPTION_CODE(x) ((x) & ~(1U << ARM_EXIT_WITH_SERROR_BIT)) #define ARM_EXCEPTION_IS_TRAP(x) (ARM_EXCEPTION_CODE((x)) == ARM_EXCEPTION_TRAP) @@ -38,17 +36,34 @@ #define __SMCCC_WORKAROUND_1_SMC_SZ 36 +#define KVM_HOST_SMCCC_ID(id) \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + (id)) + +#define KVM_HOST_SMCCC_FUNC(name) KVM_HOST_SMCCC_ID(__KVM_HOST_SMCCC_FUNC_##name) + +#define __KVM_HOST_SMCCC_FUNC___kvm_hyp_init 0 +#define __KVM_HOST_SMCCC_FUNC___kvm_vcpu_run 1 +#define __KVM_HOST_SMCCC_FUNC___kvm_flush_vm_context 2 +#define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid_ipa 3 +#define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_vmid 4 +#define __KVM_HOST_SMCCC_FUNC___kvm_tlb_flush_local_vmid 5 +#define __KVM_HOST_SMCCC_FUNC___kvm_timer_set_cntvoff 6 +#define __KVM_HOST_SMCCC_FUNC___kvm_enable_ssbs 7 +#define __KVM_HOST_SMCCC_FUNC___vgic_v3_get_ich_vtr_el2 8 +#define __KVM_HOST_SMCCC_FUNC___vgic_v3_read_vmcr 9 +#define __KVM_HOST_SMCCC_FUNC___vgic_v3_write_vmcr 10 +#define __KVM_HOST_SMCCC_FUNC___vgic_v3_init_lrs 11 +#define __KVM_HOST_SMCCC_FUNC___kvm_get_mdcr_el2 12 +#define __KVM_HOST_SMCCC_FUNC___vgic_v3_save_aprs 13 +#define __KVM_HOST_SMCCC_FUNC___vgic_v3_restore_aprs 14 + #ifndef __ASSEMBLY__ #include <linux/mm.h> -/* - * Translate name of a symbol defined in nVHE hyp to the name seen - * by kernel proper. All nVHE symbols are prefixed by the build system - * to avoid clashes with the VHE variants. - */ -#define kvm_nvhe_sym(sym) __kvm_nvhe_##sym - #define DECLARE_KVM_VHE_SYM(sym) extern char sym[] #define DECLARE_KVM_NVHE_SYM(sym) extern char kvm_nvhe_sym(sym)[] @@ -60,10 +75,53 @@ DECLARE_KVM_VHE_SYM(sym); \ DECLARE_KVM_NVHE_SYM(sym) +#define DECLARE_KVM_VHE_PER_CPU(type, sym) \ + DECLARE_PER_CPU(type, sym) +#define DECLARE_KVM_NVHE_PER_CPU(type, sym) \ + DECLARE_PER_CPU(type, kvm_nvhe_sym(sym)) + +#define DECLARE_KVM_HYP_PER_CPU(type, sym) \ + DECLARE_KVM_VHE_PER_CPU(type, sym); \ + DECLARE_KVM_NVHE_PER_CPU(type, sym) + +/* + * Compute pointer to a symbol defined in nVHE percpu region. + * Returns NULL if percpu memory has not been allocated yet. + */ +#define this_cpu_ptr_nvhe_sym(sym) per_cpu_ptr_nvhe_sym(sym, smp_processor_id()) +#define per_cpu_ptr_nvhe_sym(sym, cpu) \ + ({ \ + unsigned long base, off; \ + base = kvm_arm_hyp_percpu_base[cpu]; \ + off = (unsigned long)&CHOOSE_NVHE_SYM(sym) - \ + (unsigned long)&CHOOSE_NVHE_SYM(__per_cpu_start); \ + base ? (typeof(CHOOSE_NVHE_SYM(sym))*)(base + off) : NULL; \ + }) + +#if defined(__KVM_NVHE_HYPERVISOR__) + +#define CHOOSE_NVHE_SYM(sym) sym +#define CHOOSE_HYP_SYM(sym) CHOOSE_NVHE_SYM(sym) + +/* The nVHE hypervisor shouldn't even try to access VHE symbols */ +extern void *__nvhe_undefined_symbol; +#define CHOOSE_VHE_SYM(sym) __nvhe_undefined_symbol +#define this_cpu_ptr_hyp_sym(sym) (&__nvhe_undefined_symbol) +#define per_cpu_ptr_hyp_sym(sym, cpu) (&__nvhe_undefined_symbol) + +#elif defined(__KVM_VHE_HYPERVISOR__) + #define CHOOSE_VHE_SYM(sym) sym -#define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) +#define CHOOSE_HYP_SYM(sym) CHOOSE_VHE_SYM(sym) + +/* The VHE hypervisor shouldn't even try to access nVHE symbols */ +extern void *__vhe_undefined_symbol; +#define CHOOSE_NVHE_SYM(sym) __vhe_undefined_symbol +#define this_cpu_ptr_hyp_sym(sym) (&__vhe_undefined_symbol) +#define per_cpu_ptr_hyp_sym(sym, cpu) (&__vhe_undefined_symbol) + +#else -#ifndef __KVM_NVHE_HYPERVISOR__ /* * BIG FAT WARNINGS: * @@ -75,12 +133,21 @@ * - Don't let the nVHE hypervisor have access to this, as it will * pick the *wrong* symbol (yes, it runs at EL2...). */ -#define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() ? CHOOSE_VHE_SYM(sym) \ +#define CHOOSE_HYP_SYM(sym) (is_kernel_in_hyp_mode() \ + ? CHOOSE_VHE_SYM(sym) \ : CHOOSE_NVHE_SYM(sym)) -#else -/* The nVHE hypervisor shouldn't even try to access anything */ -extern void *__nvhe_undefined_symbol; -#define CHOOSE_HYP_SYM(sym) __nvhe_undefined_symbol + +#define this_cpu_ptr_hyp_sym(sym) (is_kernel_in_hyp_mode() \ + ? this_cpu_ptr(&sym) \ + : this_cpu_ptr_nvhe_sym(sym)) + +#define per_cpu_ptr_hyp_sym(sym, cpu) (is_kernel_in_hyp_mode() \ + ? per_cpu_ptr(&sym, cpu) \ + : per_cpu_ptr_nvhe_sym(sym, cpu)) + +#define CHOOSE_VHE_SYM(sym) sym +#define CHOOSE_NVHE_SYM(sym) kvm_nvhe_sym(sym) + #endif /* Translate a kernel address @ptr into its equivalent linear mapping */ @@ -98,15 +165,19 @@ struct kvm_vcpu; struct kvm_s2_mmu; DECLARE_KVM_NVHE_SYM(__kvm_hyp_init); +DECLARE_KVM_NVHE_SYM(__kvm_hyp_host_vector); DECLARE_KVM_HYP_SYM(__kvm_hyp_vector); #define __kvm_hyp_init CHOOSE_NVHE_SYM(__kvm_hyp_init) +#define __kvm_hyp_host_vector CHOOSE_NVHE_SYM(__kvm_hyp_host_vector) #define __kvm_hyp_vector CHOOSE_HYP_SYM(__kvm_hyp_vector) -#ifdef CONFIG_KVM_INDIRECT_VECTORS +extern unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; +DECLARE_KVM_NVHE_SYM(__per_cpu_start); +DECLARE_KVM_NVHE_SYM(__per_cpu_end); + extern atomic_t arm64_el2_vector_last_slot; DECLARE_KVM_HYP_SYM(__bp_harden_hyp_vecs); #define __bp_harden_hyp_vecs CHOOSE_HYP_SYM(__bp_harden_hyp_vecs) -#endif extern void __kvm_flush_vm_context(void); extern void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, @@ -149,26 +220,6 @@ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; addr; \ }) -/* - * Home-grown __this_cpu_{ptr,read} variants that always work at HYP, - * provided that sym is really a *symbol* and not a pointer obtained from - * a data structure. As for SHIFT_PERCPU_PTR(), the creative casting keeps - * sparse quiet. - */ -#define __hyp_this_cpu_ptr(sym) \ - ({ \ - void *__ptr; \ - __verify_pcpu_ptr(&sym); \ - __ptr = hyp_symbol_addr(sym); \ - __ptr += read_sysreg(tpidr_el2); \ - (typeof(sym) __kernel __force *)__ptr; \ - }) - -#define __hyp_this_cpu_read(sym) \ - ({ \ - *__hyp_this_cpu_ptr(sym); \ - }) - #define __KVM_EXTABLE(from, to) \ " .pushsection __kvm_ex_table, \"a\"\n" \ " .align 3\n" \ @@ -199,20 +250,8 @@ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; #else /* __ASSEMBLY__ */ -.macro hyp_adr_this_cpu reg, sym, tmp - adr_l \reg, \sym - mrs \tmp, tpidr_el2 - add \reg, \reg, \tmp -.endm - -.macro hyp_ldr_this_cpu reg, sym, tmp - adr_l \reg, \sym - mrs \tmp, tpidr_el2 - ldr \reg, [\reg, \tmp] -.endm - .macro get_host_ctxt reg, tmp - hyp_adr_this_cpu \reg, kvm_host_data, \tmp + adr_this_cpu \reg, kvm_host_data, \tmp add \reg, \reg, #HOST_DATA_CONTEXT .endm @@ -221,6 +260,16 @@ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] .endm +.macro get_loaded_vcpu vcpu, ctxt + adr_this_cpu \ctxt, kvm_hyp_ctxt, \vcpu + ldr \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] +.endm + +.macro set_loaded_vcpu vcpu, ctxt, tmp + adr_this_cpu \ctxt, kvm_hyp_ctxt, \tmp + str \vcpu, [\ctxt, #HOST_CONTEXT_VCPU] +.endm + /* * KVM extable for unexpected exceptions. * In the same format _asm_extable, but output to a different section so that @@ -236,6 +285,45 @@ extern char __smccc_workaround_1_smc[__SMCCC_WORKAROUND_1_SMC_SZ]; .popsection .endm +#define CPU_XREG_OFFSET(x) (CPU_USER_PT_REGS + 8*x) +#define CPU_LR_OFFSET CPU_XREG_OFFSET(30) +#define CPU_SP_EL0_OFFSET (CPU_LR_OFFSET + 8) + +/* + * We treat x18 as callee-saved as the host may use it as a platform + * register (e.g. for shadow call stack). + */ +.macro save_callee_saved_regs ctxt + str x18, [\ctxt, #CPU_XREG_OFFSET(18)] + stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] + stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] + stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] + stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] + stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] + stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] +.endm + +.macro restore_callee_saved_regs ctxt + // We require \ctxt is not x18-x28 + ldr x18, [\ctxt, #CPU_XREG_OFFSET(18)] + ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] + ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] + ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] + ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] + ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] + ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] +.endm + +.macro save_sp_el0 ctxt, tmp + mrs \tmp, sp_el0 + str \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] +.endm + +.macro restore_sp_el0 ctxt, tmp + ldr \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] + msr sp_el0, \tmp +.endm + #endif #endif /* __ARM_KVM_ASM_H__ */ diff --git a/arch/arm64/include/asm/kvm_emulate.h b/arch/arm64/include/asm/kvm_emulate.h index 1cc5f5f72d0b..5ef2669ccd6c 100644 --- a/arch/arm64/include/asm/kvm_emulate.h +++ b/arch/arm64/include/asm/kvm_emulate.h @@ -391,20 +391,6 @@ static inline unsigned long kvm_vcpu_get_mpidr_aff(struct kvm_vcpu *vcpu) return vcpu_read_sys_reg(vcpu, MPIDR_EL1) & MPIDR_HWID_BITMASK; } -static inline bool kvm_arm_get_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu) -{ - return vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG; -} - -static inline void kvm_arm_set_vcpu_workaround_2_flag(struct kvm_vcpu *vcpu, - bool flag) -{ - if (flag) - vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG; - else - vcpu->arch.workaround_flags &= ~VCPU_WORKAROUND_2_FLAG; -} - static inline void kvm_vcpu_set_be(struct kvm_vcpu *vcpu) { if (vcpu_mode_is_32bit(vcpu)) { diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 905c2b87e05a..0aecbab6a7fb 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -11,6 +11,7 @@ #ifndef __ARM64_KVM_HOST_H__ #define __ARM64_KVM_HOST_H__ +#include <linux/arm-smccc.h> #include <linux/bitmap.h> #include <linux/types.h> #include <linux/jump_label.h> @@ -79,8 +80,8 @@ struct kvm_s2_mmu { * for vEL1/EL0 with vHCR_EL2.VM == 0. In that case, we use the * canonical stage-2 page tables. */ - pgd_t *pgd; phys_addr_t pgd_phys; + struct kvm_pgtable *pgt; /* The last vcpu id that ran on each physical CPU */ int __percpu *last_vcpu_ran; @@ -110,6 +111,13 @@ struct kvm_arch { * supported. */ bool return_nisv_io_abort_to_user; + + /* + * VM-wide PMU filter, implemented as a bitmap and big enough for + * up to 2^10 events (ARMv8.0) or 2^16 events (ARMv8.1+). + */ + unsigned long *pmu_filter; + unsigned int pmuver; }; struct kvm_vcpu_fault_info { @@ -262,8 +270,6 @@ struct kvm_host_data { struct kvm_pmu_events pmu_events; }; -typedef struct kvm_host_data kvm_host_data_t; - struct vcpu_reset_state { unsigned long pc; unsigned long r0; @@ -480,18 +486,15 @@ int kvm_test_age_hva(struct kvm *kvm, unsigned long hva); void kvm_arm_halt_guest(struct kvm *kvm); void kvm_arm_resume_guest(struct kvm *kvm); -u64 __kvm_call_hyp(void *hypfn, ...); - -#define kvm_call_hyp_nvhe(f, ...) \ - do { \ - DECLARE_KVM_NVHE_SYM(f); \ - __kvm_call_hyp(kvm_ksym_ref_nvhe(f), ##__VA_ARGS__); \ - } while(0) - -#define kvm_call_hyp_nvhe_ret(f, ...) \ +#define kvm_call_hyp_nvhe(f, ...) \ ({ \ - DECLARE_KVM_NVHE_SYM(f); \ - __kvm_call_hyp(kvm_ksym_ref_nvhe(f), ##__VA_ARGS__); \ + struct arm_smccc_res res; \ + \ + arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(f), \ + ##__VA_ARGS__, &res); \ + WARN_ON(res.a0 != SMCCC_RET_SUCCESS); \ + \ + res.a1; \ }) /* @@ -517,7 +520,7 @@ u64 __kvm_call_hyp(void *hypfn, ...); ret = f(__VA_ARGS__); \ isb(); \ } else { \ - ret = kvm_call_hyp_nvhe_ret(f, ##__VA_ARGS__); \ + ret = kvm_call_hyp_nvhe(f, ##__VA_ARGS__); \ } \ \ ret; \ @@ -565,7 +568,7 @@ void kvm_set_sei_esr(struct kvm_vcpu *vcpu, u64 syndrome); struct kvm_vcpu *kvm_mpidr_to_vcpu(struct kvm *kvm, unsigned long mpidr); -DECLARE_PER_CPU(kvm_host_data_t, kvm_host_data); +DECLARE_KVM_HYP_PER_CPU(struct kvm_host_data, kvm_host_data); static inline void kvm_init_host_cpu_context(struct kvm_cpu_context *cpu_ctxt) { @@ -631,46 +634,6 @@ static inline void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) {} static inline void kvm_clr_pmu_events(u32 clr) {} #endif -#define KVM_BP_HARDEN_UNKNOWN -1 -#define KVM_BP_HARDEN_WA_NEEDED 0 -#define KVM_BP_HARDEN_NOT_REQUIRED 1 - -static inline int kvm_arm_harden_branch_predictor(void) -{ - switch (get_spectre_v2_workaround_state()) { - case ARM64_BP_HARDEN_WA_NEEDED: - return KVM_BP_HARDEN_WA_NEEDED; - case ARM64_BP_HARDEN_NOT_REQUIRED: - return KVM_BP_HARDEN_NOT_REQUIRED; - case ARM64_BP_HARDEN_UNKNOWN: - default: - return KVM_BP_HARDEN_UNKNOWN; - } -} - -#define KVM_SSBD_UNKNOWN -1 -#define KVM_SSBD_FORCE_DISABLE 0 -#define KVM_SSBD_KERNEL 1 -#define KVM_SSBD_FORCE_ENABLE 2 -#define KVM_SSBD_MITIGATED 3 - -static inline int kvm_arm_have_ssbd(void) -{ - switch (arm64_get_ssbd_state()) { - case ARM64_SSBD_FORCE_DISABLE: - return KVM_SSBD_FORCE_DISABLE; - case ARM64_SSBD_KERNEL: - return KVM_SSBD_KERNEL; - case ARM64_SSBD_FORCE_ENABLE: - return KVM_SSBD_FORCE_ENABLE; - case ARM64_SSBD_MITIGATED: - return KVM_SSBD_MITIGATED; - case ARM64_SSBD_UNKNOWN: - default: - return KVM_SSBD_UNKNOWN; - } -} - void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu); void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu); diff --git a/arch/arm64/include/asm/kvm_hyp.h b/arch/arm64/include/asm/kvm_hyp.h index 46689e7db46c..6b664de5ec1f 100644 --- a/arch/arm64/include/asm/kvm_hyp.h +++ b/arch/arm64/include/asm/kvm_hyp.h @@ -12,6 +12,9 @@ #include <asm/alternative.h> #include <asm/sysreg.h> +DECLARE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); +DECLARE_PER_CPU(unsigned long, kvm_hyp_vector); + #define read_sysreg_elx(r,nvh,vh) \ ({ \ u64 reg; \ @@ -87,11 +90,11 @@ void activate_traps_vhe_load(struct kvm_vcpu *vcpu); void deactivate_traps_vhe_put(void); #endif -u64 __guest_enter(struct kvm_vcpu *vcpu, struct kvm_cpu_context *host_ctxt); +u64 __guest_enter(struct kvm_vcpu *vcpu); -void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt); +void __noreturn hyp_panic(void); #ifdef __KVM_NVHE_HYPERVISOR__ -void __noreturn __hyp_do_panic(unsigned long, ...); +void __noreturn __hyp_do_panic(bool restore_host, u64 spsr, u64 elr, u64 par); #endif #endif /* __ARM64_KVM_HYP_H__ */ diff --git a/arch/arm64/include/asm/kvm_mmu.h b/arch/arm64/include/asm/kvm_mmu.h index 189839c3706a..331394306cce 100644 --- a/arch/arm64/include/asm/kvm_mmu.h +++ b/arch/arm64/include/asm/kvm_mmu.h @@ -9,6 +9,7 @@ #include <asm/page.h> #include <asm/memory.h> +#include <asm/mmu.h> #include <asm/cpufeature.h> /* @@ -43,16 +44,6 @@ * HYP_VA_MIN = 1 << (VA_BITS - 1) * HYP_VA_MAX = HYP_VA_MIN + (1 << (VA_BITS - 1)) - 1 * - * This of course assumes that the trampoline page exists within the - * VA_BITS range. If it doesn't, then it means we're in the odd case - * where the kernel idmap (as well as HYP) uses more levels than the - * kernel runtime page tables (as seen when the kernel is configured - * for 4k pages, 39bits VA, and yet memory lives just above that - * limit, forcing the idmap to use 4 levels of page tables while the - * kernel itself only uses 3). In this particular case, it doesn't - * matter which side of VA_BITS we use, as we're guaranteed not to - * conflict with anything. - * * When using VHE, there are no separate hyp mappings and all KVM * functionality is already mapped as part of the main kernel * mappings, and none of this applies in that case. @@ -117,15 +108,10 @@ static __always_inline unsigned long __kern_hyp_va(unsigned long v) #define kvm_phys_size(kvm) (_AC(1, ULL) << kvm_phys_shift(kvm)) #define kvm_phys_mask(kvm) (kvm_phys_size(kvm) - _AC(1, ULL)) -static inline bool kvm_page_empty(void *ptr) -{ - struct page *ptr_page = virt_to_page(ptr); - return page_count(ptr_page) == 1; -} - +#include <asm/kvm_pgtable.h> #include <asm/stage2_pgtable.h> -int create_hyp_mappings(void *from, void *to, pgprot_t prot); +int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot); int create_hyp_io_mappings(phys_addr_t phys_addr, size_t size, void __iomem **kaddr, void __iomem **haddr); @@ -141,149 +127,9 @@ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, int kvm_handle_guest_abort(struct kvm_vcpu *vcpu); -void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu); - phys_addr_t kvm_mmu_get_httbr(void); phys_addr_t kvm_get_idmap_vector(void); int kvm_mmu_init(void); -void kvm_clear_hyp_idmap(void); - -#define kvm_mk_pmd(ptep) \ - __pmd(__phys_to_pmd_val(__pa(ptep)) | PMD_TYPE_TABLE) -#define kvm_mk_pud(pmdp) \ - __pud(__phys_to_pud_val(__pa(pmdp)) | PMD_TYPE_TABLE) -#define kvm_mk_p4d(pmdp) \ - __p4d(__phys_to_p4d_val(__pa(pmdp)) | PUD_TYPE_TABLE) - -#define kvm_set_pud(pudp, pud) set_pud(pudp, pud) - -#define kvm_pfn_pte(pfn, prot) pfn_pte(pfn, prot) -#define kvm_pfn_pmd(pfn, prot) pfn_pmd(pfn, prot) -#define kvm_pfn_pud(pfn, prot) pfn_pud(pfn, prot) - -#define kvm_pud_pfn(pud) pud_pfn(pud) - -#define kvm_pmd_mkhuge(pmd) pmd_mkhuge(pmd) -#define kvm_pud_mkhuge(pud) pud_mkhuge(pud) - -static inline pte_t kvm_s2pte_mkwrite(pte_t pte) -{ - pte_val(pte) |= PTE_S2_RDWR; - return pte; -} - -static inline pmd_t kvm_s2pmd_mkwrite(pmd_t pmd) -{ - pmd_val(pmd) |= PMD_S2_RDWR; - return pmd; -} - -static inline pud_t kvm_s2pud_mkwrite(pud_t pud) -{ - pud_val(pud) |= PUD_S2_RDWR; - return pud; -} - -static inline pte_t kvm_s2pte_mkexec(pte_t pte) -{ - pte_val(pte) &= ~PTE_S2_XN; - return pte; -} - -static inline pmd_t kvm_s2pmd_mkexec(pmd_t pmd) -{ - pmd_val(pmd) &= ~PMD_S2_XN; - return pmd; -} - -static inline pud_t kvm_s2pud_mkexec(pud_t pud) -{ - pud_val(pud) &= ~PUD_S2_XN; - return pud; -} - -static inline void kvm_set_s2pte_readonly(pte_t *ptep) -{ - pteval_t old_pteval, pteval; - - pteval = READ_ONCE(pte_val(*ptep)); - do { - old_pteval = pteval; - pteval &= ~PTE_S2_RDWR; - pteval |= PTE_S2_RDONLY; - pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval); - } while (pteval != old_pteval); -} - -static inline bool kvm_s2pte_readonly(pte_t *ptep) -{ - return (READ_ONCE(pte_val(*ptep)) & PTE_S2_RDWR) == PTE_S2_RDONLY; -} - -static inline bool kvm_s2pte_exec(pte_t *ptep) -{ - return !(READ_ONCE(pte_val(*ptep)) & PTE_S2_XN); -} - -static inline void kvm_set_s2pmd_readonly(pmd_t *pmdp) -{ - kvm_set_s2pte_readonly((pte_t *)pmdp); -} - -static inline bool kvm_s2pmd_readonly(pmd_t *pmdp) -{ - return kvm_s2pte_readonly((pte_t *)pmdp); -} - -static inline bool kvm_s2pmd_exec(pmd_t *pmdp) -{ - return !(READ_ONCE(pmd_val(*pmdp)) & PMD_S2_XN); -} - -static inline void kvm_set_s2pud_readonly(pud_t *pudp) -{ - kvm_set_s2pte_readonly((pte_t *)pudp); -} - -static inline bool kvm_s2pud_readonly(pud_t *pudp) -{ - return kvm_s2pte_readonly((pte_t *)pudp); -} - -static inline bool kvm_s2pud_exec(pud_t *pudp) -{ - return !(READ_ONCE(pud_val(*pudp)) & PUD_S2_XN); -} - -static inline pud_t kvm_s2pud_mkyoung(pud_t pud) -{ - return pud_mkyoung(pud); -} - -static inline bool kvm_s2pud_young(pud_t pud) -{ - return pud_young(pud); -} - -#define hyp_pte_table_empty(ptep) kvm_page_empty(ptep) - -#ifdef __PAGETABLE_PMD_FOLDED -#define hyp_pmd_table_empty(pmdp) (0) -#else -#define hyp_pmd_table_empty(pmdp) kvm_page_empty(pmdp) -#endif - -#ifdef __PAGETABLE_PUD_FOLDED -#define hyp_pud_table_empty(pudp) (0) -#else -#define hyp_pud_table_empty(pudp) kvm_page_empty(pudp) -#endif - -#ifdef __PAGETABLE_P4D_FOLDED -#define hyp_p4d_table_empty(p4dp) (0) -#else -#define hyp_p4d_table_empty(p4dp) kvm_page_empty(p4dp) -#endif struct kvm; @@ -325,77 +171,9 @@ static inline void __invalidate_icache_guest_page(kvm_pfn_t pfn, } } -static inline void __kvm_flush_dcache_pte(pte_t pte) -{ - if (!cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) { - struct page *page = pte_page(pte); - kvm_flush_dcache_to_poc(page_address(page), PAGE_SIZE); - } -} - -static inline void __kvm_flush_dcache_pmd(pmd_t pmd) -{ - if (!cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) { - struct page *page = pmd_page(pmd); - kvm_flush_dcache_to_poc(page_address(page), PMD_SIZE); - } -} - -static inline void __kvm_flush_dcache_pud(pud_t pud) -{ - if (!cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) { - struct page *page = pud_page(pud); - kvm_flush_dcache_to_poc(page_address(page), PUD_SIZE); - } -} - void kvm_set_way_flush(struct kvm_vcpu *vcpu); void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled); -static inline bool __kvm_cpu_uses_extended_idmap(void) -{ - return __cpu_uses_extended_idmap_level(); -} - -static inline unsigned long __kvm_idmap_ptrs_per_pgd(void) -{ - return idmap_ptrs_per_pgd; -} - -/* - * Can't use pgd_populate here, because the extended idmap adds an extra level - * above CONFIG_PGTABLE_LEVELS (which is 2 or 3 if we're using the extended - * idmap), and pgd_populate is only available if CONFIG_PGTABLE_LEVELS = 4. - */ -static inline void __kvm_extend_hypmap(pgd_t *boot_hyp_pgd, - pgd_t *hyp_pgd, - pgd_t *merged_hyp_pgd, - unsigned long hyp_idmap_start) -{ - int idmap_idx; - u64 pgd_addr; - - /* - * Use the first entry to access the HYP mappings. It is - * guaranteed to be free, otherwise we wouldn't use an - * extended idmap. - */ - VM_BUG_ON(pgd_val(merged_hyp_pgd[0])); - pgd_addr = __phys_to_pgd_val(__pa(hyp_pgd)); - merged_hyp_pgd[0] = __pgd(pgd_addr | PMD_TYPE_TABLE); - - /* - * Create another extended level entry that points to the boot HYP map, - * which contains an ID mapping of the HYP init code. We essentially - * merge the boot and runtime HYP maps by doing so, but they don't - * overlap anyway, so this is fine. - */ - idmap_idx = hyp_idmap_start >> VA_BITS; - VM_BUG_ON(pgd_val(merged_hyp_pgd[idmap_idx])); - pgd_addr = __phys_to_pgd_val(__pa(boot_hyp_pgd)); - merged_hyp_pgd[idmap_idx] = __pgd(pgd_addr | PMD_TYPE_TABLE); -} - static inline unsigned int kvm_get_vmid_bits(void) { int reg = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1); @@ -430,19 +208,17 @@ static inline int kvm_write_guest_lock(struct kvm *kvm, gpa_t gpa, return ret; } -#ifdef CONFIG_KVM_INDIRECT_VECTORS /* * EL2 vectors can be mapped and rerouted in a number of ways, * depending on the kernel configuration and CPU present: * - * - If the CPU has the ARM64_HARDEN_BRANCH_PREDICTOR cap, the - * hardening sequence is placed in one of the vector slots, which is - * executed before jumping to the real vectors. + * - If the CPU is affected by Spectre-v2, the hardening sequence is + * placed in one of the vector slots, which is executed before jumping + * to the real vectors. * - * - If the CPU has both the ARM64_HARDEN_EL2_VECTORS cap and the - * ARM64_HARDEN_BRANCH_PREDICTOR cap, the slot containing the - * hardening sequence is mapped next to the idmap page, and executed - * before jumping to the real vectors. + * - If the CPU also has the ARM64_HARDEN_EL2_VECTORS cap, the slot + * containing the hardening sequence is mapped next to the idmap page, + * and executed before jumping to the real vectors. * * - If the CPU only has the ARM64_HARDEN_EL2_VECTORS cap, then an * empty slot is selected, mapped next to the idmap page, and @@ -452,19 +228,16 @@ static inline int kvm_write_guest_lock(struct kvm *kvm, gpa_t gpa, * VHE, as we don't have hypervisor-specific mappings. If the system * is VHE and yet selects this capability, it will be ignored. */ -#include <asm/mmu.h> - extern void *__kvm_bp_vect_base; extern int __kvm_harden_el2_vector_slot; -/* This is called on both VHE and !VHE systems */ static inline void *kvm_get_hyp_vector(void) { struct bp_hardening_data *data = arm64_get_bp_hardening_data(); void *vect = kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); int slot = -1; - if (cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR) && data->fn) { + if (cpus_have_const_cap(ARM64_SPECTRE_V2) && data->fn) { vect = kern_hyp_va(kvm_ksym_ref(__bp_harden_hyp_vecs)); slot = data->hyp_vectors_slot; } @@ -481,102 +254,8 @@ static inline void *kvm_get_hyp_vector(void) return vect; } -/* This is only called on a !VHE system */ -static inline int kvm_map_vectors(void) -{ - /* - * HBP = ARM64_HARDEN_BRANCH_PREDICTOR - * HEL2 = ARM64_HARDEN_EL2_VECTORS - * - * !HBP + !HEL2 -> use direct vectors - * HBP + !HEL2 -> use hardened vectors in place - * !HBP + HEL2 -> allocate one vector slot and use exec mapping - * HBP + HEL2 -> use hardened vertors and use exec mapping - */ - if (cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR)) { - __kvm_bp_vect_base = kvm_ksym_ref(__bp_harden_hyp_vecs); - __kvm_bp_vect_base = kern_hyp_va(__kvm_bp_vect_base); - } - - if (cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)) { - phys_addr_t vect_pa = __pa_symbol(__bp_harden_hyp_vecs); - unsigned long size = __BP_HARDEN_HYP_VECS_SZ; - - /* - * Always allocate a spare vector slot, as we don't - * know yet which CPUs have a BP hardening slot that - * we can reuse. - */ - __kvm_harden_el2_vector_slot = atomic_inc_return(&arm64_el2_vector_last_slot); - BUG_ON(__kvm_harden_el2_vector_slot >= BP_HARDEN_EL2_SLOTS); - return create_hyp_exec_mappings(vect_pa, size, - &__kvm_bp_vect_base); - } - - return 0; -} -#else -static inline void *kvm_get_hyp_vector(void) -{ - return kern_hyp_va(kvm_ksym_ref(__kvm_hyp_vector)); -} - -static inline int kvm_map_vectors(void) -{ - return 0; -} -#endif - -#ifdef CONFIG_ARM64_SSBD -DECLARE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required); - -static inline int hyp_map_aux_data(void) -{ - int cpu, err; - - for_each_possible_cpu(cpu) { - u64 *ptr; - - ptr = per_cpu_ptr(&arm64_ssbd_callback_required, cpu); - err = create_hyp_mappings(ptr, ptr + 1, PAGE_HYP); - if (err) - return err; - } - return 0; -} -#else -static inline int hyp_map_aux_data(void) -{ - return 0; -} -#endif - #define kvm_phys_to_vttbr(addr) phys_to_ttbr(addr) -/* - * Get the magic number 'x' for VTTBR:BADDR of this KVM instance. - * With v8.2 LVA extensions, 'x' should be a minimum of 6 with - * 52bit IPS. - */ -static inline int arm64_vttbr_x(u32 ipa_shift, u32 levels) -{ - int x = ARM64_VTTBR_X(ipa_shift, levels); - - return (IS_ENABLED(CONFIG_ARM64_PA_BITS_52) && x < 6) ? 6 : x; -} - -static inline u64 vttbr_baddr_mask(u32 ipa_shift, u32 levels) -{ - unsigned int x = arm64_vttbr_x(ipa_shift, levels); - - return GENMASK_ULL(PHYS_MASK_SHIFT - 1, x); -} - -static inline u64 kvm_vttbr_baddr_mask(struct kvm *kvm) -{ - return vttbr_baddr_mask(kvm_phys_shift(kvm), kvm_stage2_levels(kvm)); -} - static __always_inline u64 kvm_get_vttbr(struct kvm_s2_mmu *mmu) { struct kvm_vmid *vmid = &mmu->vmid; diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h new file mode 100644 index 000000000000..52ab38db04c7 --- /dev/null +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -0,0 +1,309 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 Google LLC + * Author: Will Deacon <will@kernel.org> + */ + +#ifndef __ARM64_KVM_PGTABLE_H__ +#define __ARM64_KVM_PGTABLE_H__ + +#include <linux/bits.h> +#include <linux/kvm_host.h> +#include <linux/types.h> + +typedef u64 kvm_pte_t; + +/** + * struct kvm_pgtable - KVM page-table. + * @ia_bits: Maximum input address size, in bits. + * @start_level: Level at which the page-table walk starts. + * @pgd: Pointer to the first top-level entry of the page-table. + * @mmu: Stage-2 KVM MMU struct. Unused for stage-1 page-tables. + */ +struct kvm_pgtable { + u32 ia_bits; + u32 start_level; + kvm_pte_t *pgd; + + /* Stage-2 only */ + struct kvm_s2_mmu *mmu; +}; + +/** + * enum kvm_pgtable_prot - Page-table permissions and attributes. + * @KVM_PGTABLE_PROT_X: Execute permission. + * @KVM_PGTABLE_PROT_W: Write permission. + * @KVM_PGTABLE_PROT_R: Read permission. + * @KVM_PGTABLE_PROT_DEVICE: Device attributes. + */ +enum kvm_pgtable_prot { + KVM_PGTABLE_PROT_X = BIT(0), + KVM_PGTABLE_PROT_W = BIT(1), + KVM_PGTABLE_PROT_R = BIT(2), + + KVM_PGTABLE_PROT_DEVICE = BIT(3), +}; + +#define PAGE_HYP (KVM_PGTABLE_PROT_R | KVM_PGTABLE_PROT_W) +#define PAGE_HYP_EXEC (KVM_PGTABLE_PROT_R | KVM_PGTABLE_PROT_X) +#define PAGE_HYP_RO (KVM_PGTABLE_PROT_R) +#define PAGE_HYP_DEVICE (PAGE_HYP | KVM_PGTABLE_PROT_DEVICE) + +/** + * enum kvm_pgtable_walk_flags - Flags to control a depth-first page-table walk. + * @KVM_PGTABLE_WALK_LEAF: Visit leaf entries, including invalid + * entries. + * @KVM_PGTABLE_WALK_TABLE_PRE: Visit table entries before their + * children. + * @KVM_PGTABLE_WALK_TABLE_POST: Visit table entries after their + * children. + */ +enum kvm_pgtable_walk_flags { + KVM_PGTABLE_WALK_LEAF = BIT(0), + KVM_PGTABLE_WALK_TABLE_PRE = BIT(1), + KVM_PGTABLE_WALK_TABLE_POST = BIT(2), +}; + +typedef int (*kvm_pgtable_visitor_fn_t)(u64 addr, u64 end, u32 level, + kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, + void * const arg); + +/** + * struct kvm_pgtable_walker - Hook into a page-table walk. + * @cb: Callback function to invoke during the walk. + * @arg: Argument passed to the callback function. + * @flags: Bitwise-OR of flags to identify the entry types on which to + * invoke the callback function. + */ +struct kvm_pgtable_walker { + const kvm_pgtable_visitor_fn_t cb; + void * const arg; + const enum kvm_pgtable_walk_flags flags; +}; + +/** + * kvm_pgtable_hyp_init() - Initialise a hypervisor stage-1 page-table. + * @pgt: Uninitialised page-table structure to initialise. + * @va_bits: Maximum virtual address bits. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_hyp_init(struct kvm_pgtable *pgt, u32 va_bits); + +/** + * kvm_pgtable_hyp_destroy() - Destroy an unused hypervisor stage-1 page-table. + * @pgt: Page-table structure initialised by kvm_pgtable_hyp_init(). + * + * The page-table is assumed to be unreachable by any hardware walkers prior + * to freeing and therefore no TLB invalidation is performed. + */ +void kvm_pgtable_hyp_destroy(struct kvm_pgtable *pgt); + +/** + * kvm_pgtable_hyp_map() - Install a mapping in a hypervisor stage-1 page-table. + * @pgt: Page-table structure initialised by kvm_pgtable_hyp_init(). + * @addr: Virtual address at which to place the mapping. + * @size: Size of the mapping. + * @phys: Physical address of the memory to map. + * @prot: Permissions and attributes for the mapping. + * + * The offset of @addr within a page is ignored, @size is rounded-up to + * the next page boundary and @phys is rounded-down to the previous page + * boundary. + * + * If device attributes are not explicitly requested in @prot, then the + * mapping will be normal, cacheable. Attempts to install a new mapping + * for a virtual address that is already mapped will be rejected with an + * error and a WARN(). + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_hyp_map(struct kvm_pgtable *pgt, u64 addr, u64 size, u64 phys, + enum kvm_pgtable_prot prot); + +/** + * kvm_pgtable_stage2_init() - Initialise a guest stage-2 page-table. + * @pgt: Uninitialised page-table structure to initialise. + * @kvm: KVM structure representing the guest virtual machine. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm *kvm); + +/** + * kvm_pgtable_stage2_destroy() - Destroy an unused guest stage-2 page-table. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * + * The page-table is assumed to be unreachable by any hardware walkers prior + * to freeing and therefore no TLB invalidation is performed. + */ +void kvm_pgtable_stage2_destroy(struct kvm_pgtable *pgt); + +/** + * kvm_pgtable_stage2_map() - Install a mapping in a guest stage-2 page-table. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address at which to place the mapping. + * @size: Size of the mapping. + * @phys: Physical address of the memory to map. + * @prot: Permissions and attributes for the mapping. + * @mc: Cache of pre-allocated GFP_PGTABLE_USER memory from which to + * allocate page-table pages. + * + * The offset of @addr within a page is ignored, @size is rounded-up to + * the next page boundary and @phys is rounded-down to the previous page + * boundary. + * + * If device attributes are not explicitly requested in @prot, then the + * mapping will be normal, cacheable. + * + * Note that this function will both coalesce existing table entries and split + * existing block mappings, relying on page-faults to fault back areas outside + * of the new mapping lazily. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, + u64 phys, enum kvm_pgtable_prot prot, + struct kvm_mmu_memory_cache *mc); + +/** + * kvm_pgtable_stage2_unmap() - Remove a mapping from a guest stage-2 page-table. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address from which to remove the mapping. + * @size: Size of the mapping. + * + * The offset of @addr within a page is ignored and @size is rounded-up to + * the next page boundary. + * + * TLB invalidation is performed for each page-table entry cleared during the + * unmapping operation and the reference count for the page-table page + * containing the cleared entry is decremented, with unreferenced pages being + * freed. Unmapping a cacheable page will ensure that it is clean to the PoC if + * FWB is not supported by the CPU. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size); + +/** + * kvm_pgtable_stage2_wrprotect() - Write-protect guest stage-2 address range + * without TLB invalidation. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address from which to write-protect, + * @size: Size of the range. + * + * The offset of @addr within a page is ignored and @size is rounded-up to + * the next page boundary. + * + * Note that it is the caller's responsibility to invalidate the TLB after + * calling this function to ensure that the updated permissions are visible + * to the CPUs. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size); + +/** + * kvm_pgtable_stage2_mkyoung() - Set the access flag in a page-table entry. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address to identify the page-table entry. + * + * The offset of @addr within a page is ignored. + * + * If there is a valid, leaf page-table entry used to translate @addr, then + * set the access flag in that entry. + * + * Return: The old page-table entry prior to setting the flag, 0 on failure. + */ +kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr); + +/** + * kvm_pgtable_stage2_mkold() - Clear the access flag in a page-table entry. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address to identify the page-table entry. + * + * The offset of @addr within a page is ignored. + * + * If there is a valid, leaf page-table entry used to translate @addr, then + * clear the access flag in that entry. + * + * Note that it is the caller's responsibility to invalidate the TLB after + * calling this function to ensure that the updated permissions are visible + * to the CPUs. + * + * Return: The old page-table entry prior to clearing the flag, 0 on failure. + */ +kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); + +/** + * kvm_pgtable_stage2_relax_perms() - Relax the permissions enforced by a + * page-table entry. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address to identify the page-table entry. + * @prot: Additional permissions to grant for the mapping. + * + * The offset of @addr within a page is ignored. + * + * If there is a valid, leaf page-table entry used to translate @addr, then + * relax the permissions in that entry according to the read, write and + * execute permissions specified by @prot. No permissions are removed, and + * TLB invalidation is performed after updating the entry. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, + enum kvm_pgtable_prot prot); + +/** + * kvm_pgtable_stage2_is_young() - Test whether a page-table entry has the + * access flag set. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address to identify the page-table entry. + * + * The offset of @addr within a page is ignored. + * + * Return: True if the page-table entry has the access flag set, false otherwise. + */ +bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr); + +/** + * kvm_pgtable_stage2_flush_range() - Clean and invalidate data cache to Point + * of Coherency for guest stage-2 address + * range. + * @pgt: Page-table structure initialised by kvm_pgtable_stage2_init(). + * @addr: Intermediate physical address from which to flush. + * @size: Size of the range. + * + * The offset of @addr within a page is ignored and @size is rounded-up to + * the next page boundary. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_stage2_flush(struct kvm_pgtable *pgt, u64 addr, u64 size); + +/** + * kvm_pgtable_walk() - Walk a page-table. + * @pgt: Page-table structure initialised by kvm_pgtable_*_init(). + * @addr: Input address for the start of the walk. + * @size: Size of the range to walk. + * @walker: Walker callback description. + * + * The offset of @addr within a page is ignored and @size is rounded-up to + * the next page boundary. + * + * The walker will walk the page-table entries corresponding to the input + * address range specified, visiting entries according to the walker flags. + * Invalid entries are treated as leaf entries. Leaf entries are reloaded + * after invoking the walker callback, allowing the walker to descend into + * a newly installed table. + * + * Returning a negative error code from the walker callback function will + * terminate the walk immediately with the same error code. + * + * Return: 0 on success, negative error code on failure. + */ +int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, + struct kvm_pgtable_walker *walker); + +#endif /* __ARM64_KVM_PGTABLE_H__ */ diff --git a/arch/arm64/include/asm/kvm_ptrauth.h b/arch/arm64/include/asm/kvm_ptrauth.h index 0ddf98c3ba9f..0cd0965255d2 100644 --- a/arch/arm64/include/asm/kvm_ptrauth.h +++ b/arch/arm64/include/asm/kvm_ptrauth.h @@ -60,7 +60,7 @@ .endm /* - * Both ptrauth_switch_to_guest and ptrauth_switch_to_host macros will + * Both ptrauth_switch_to_guest and ptrauth_switch_to_hyp macros will * check for the presence ARM64_HAS_ADDRESS_AUTH, which is defined as * (ARM64_HAS_ADDRESS_AUTH_ARCH || ARM64_HAS_ADDRESS_AUTH_IMP_DEF) and * then proceed ahead with the save/restore of Pointer Authentication @@ -78,7 +78,7 @@ alternative_else_nop_endif .L__skip_switch\@: .endm -.macro ptrauth_switch_to_host g_ctxt, h_ctxt, reg1, reg2, reg3 +.macro ptrauth_switch_to_hyp g_ctxt, h_ctxt, reg1, reg2, reg3 alternative_if_not ARM64_HAS_ADDRESS_AUTH b .L__skip_switch\@ alternative_else_nop_endif @@ -96,7 +96,7 @@ alternative_else_nop_endif #else /* !CONFIG_ARM64_PTR_AUTH */ .macro ptrauth_switch_to_guest g_ctxt, reg1, reg2, reg3 .endm -.macro ptrauth_switch_to_host g_ctxt, h_ctxt, reg1, reg2, reg3 +.macro ptrauth_switch_to_hyp g_ctxt, h_ctxt, reg1, reg2, reg3 .endm #endif /* CONFIG_ARM64_PTR_AUTH */ #endif /* __ASSEMBLY__ */ diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h index a7a5ecaa2e83..cbff2d42c1d8 100644 --- a/arch/arm64/include/asm/mmu.h +++ b/arch/arm64/include/asm/mmu.h @@ -45,7 +45,6 @@ struct bp_hardening_data { bp_hardening_cb_t fn; }; -#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR DECLARE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void) @@ -57,21 +56,13 @@ static inline void arm64_apply_bp_hardening(void) { struct bp_hardening_data *d; - if (!cpus_have_const_cap(ARM64_HARDEN_BRANCH_PREDICTOR)) + if (!cpus_have_const_cap(ARM64_SPECTRE_V2)) return; d = arm64_get_bp_hardening_data(); if (d->fn) d->fn(); } -#else -static inline struct bp_hardening_data *arm64_get_bp_hardening_data(void) -{ - return NULL; -} - -static inline void arm64_apply_bp_hardening(void) { } -#endif /* CONFIG_HARDEN_BRANCH_PREDICTOR */ extern void arm64_memblock_init(void); extern void paging_init(void); diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h index 0b6409b89e5e..1599e17379d8 100644 --- a/arch/arm64/include/asm/percpu.h +++ b/arch/arm64/include/asm/percpu.h @@ -19,7 +19,16 @@ static inline void set_my_cpu_offset(unsigned long off) :: "r" (off) : "memory"); } -static inline unsigned long __my_cpu_offset(void) +static inline unsigned long __hyp_my_cpu_offset(void) +{ + /* + * Non-VHE hyp code runs with preemption disabled. No need to hazard + * the register access against barrier() as in __kern_my_cpu_offset. + */ + return read_sysreg(tpidr_el2); +} + +static inline unsigned long __kern_my_cpu_offset(void) { unsigned long off; @@ -35,7 +44,12 @@ static inline unsigned long __my_cpu_offset(void) return off; } -#define __my_cpu_offset __my_cpu_offset() + +#ifdef __KVM_NVHE_HYPERVISOR__ +#define __my_cpu_offset __hyp_my_cpu_offset() +#else +#define __my_cpu_offset __kern_my_cpu_offset() +#endif #define PERCPU_RW_OPS(sz) \ static inline unsigned long __percpu_read_##sz(void *ptr) \ @@ -227,4 +241,14 @@ PERCPU_RET_OP(add, add, ldadd) #include <asm-generic/percpu.h> +/* Redefine macros for nVHE hyp under DEBUG_PREEMPT to avoid its dependencies. */ +#if defined(__KVM_NVHE_HYPERVISOR__) && defined(CONFIG_DEBUG_PREEMPT) +#undef this_cpu_ptr +#define this_cpu_ptr raw_cpu_ptr +#undef __this_cpu_read +#define __this_cpu_read raw_cpu_read +#undef __this_cpu_write +#define __this_cpu_write raw_cpu_write +#endif + #endif /* __ASM_PERCPU_H */ diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index d400a4d9aee2..2b5f822fb033 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -156,7 +156,6 @@ #define PTE_CONT (_AT(pteval_t, 1) << 52) /* Contiguous range */ #define PTE_PXN (_AT(pteval_t, 1) << 53) /* Privileged XN */ #define PTE_UXN (_AT(pteval_t, 1) << 54) /* User XN */ -#define PTE_HYP_XN (_AT(pteval_t, 1) << 54) /* HYP XN */ #define PTE_ADDR_LOW (((_AT(pteval_t, 1) << (48 - PAGE_SHIFT)) - 1) << PAGE_SHIFT) #ifdef CONFIG_ARM64_PA_BITS_52 @@ -173,34 +172,11 @@ #define PTE_ATTRINDX_MASK (_AT(pteval_t, 7) << 2) /* - * 2nd stage PTE definitions - */ -#define PTE_S2_RDONLY (_AT(pteval_t, 1) << 6) /* HAP[2:1] */ -#define PTE_S2_RDWR (_AT(pteval_t, 3) << 6) /* HAP[2:1] */ -#define PTE_S2_XN (_AT(pteval_t, 2) << 53) /* XN[1:0] */ -#define PTE_S2_SW_RESVD (_AT(pteval_t, 15) << 55) /* Reserved for SW */ - -#define PMD_S2_RDONLY (_AT(pmdval_t, 1) << 6) /* HAP[2:1] */ -#define PMD_S2_RDWR (_AT(pmdval_t, 3) << 6) /* HAP[2:1] */ -#define PMD_S2_XN (_AT(pmdval_t, 2) << 53) /* XN[1:0] */ -#define PMD_S2_SW_RESVD (_AT(pmdval_t, 15) << 55) /* Reserved for SW */ - -#define PUD_S2_RDONLY (_AT(pudval_t, 1) << 6) /* HAP[2:1] */ -#define PUD_S2_RDWR (_AT(pudval_t, 3) << 6) /* HAP[2:1] */ -#define PUD_S2_XN (_AT(pudval_t, 2) << 53) /* XN[1:0] */ - -/* * Memory Attribute override for Stage-2 (MemAttr[3:0]) */ #define PTE_S2_MEMATTR(t) (_AT(pteval_t, (t)) << 2) /* - * EL2/HYP PTE/PMD definitions - */ -#define PMD_HYP PMD_SECT_USER -#define PTE_HYP PTE_USER - -/* * Highest possible physical address supported. */ #define PHYS_MASK_SHIFT (CONFIG_ARM64_PA_BITS) diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index 4d867c6446c4..8f094c43072a 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -56,7 +56,6 @@ extern bool arm64_use_ng_mappings; #define PROT_SECT_NORMAL_EXEC (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL)) #define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL)) -#define _HYP_PAGE_DEFAULT _PAGE_DEFAULT #define PAGE_KERNEL __pgprot(PROT_NORMAL) #define PAGE_KERNEL_RO __pgprot((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY) @@ -64,11 +63,6 @@ extern bool arm64_use_ng_mappings; #define PAGE_KERNEL_EXEC __pgprot(PROT_NORMAL & ~PTE_PXN) #define PAGE_KERNEL_EXEC_CONT __pgprot((PROT_NORMAL & ~PTE_PXN) | PTE_CONT) -#define PAGE_HYP __pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_HYP_XN) -#define PAGE_HYP_EXEC __pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY) -#define PAGE_HYP_RO __pgprot(_HYP_PAGE_DEFAULT | PTE_HYP | PTE_RDONLY | PTE_HYP_XN) -#define PAGE_HYP_DEVICE __pgprot(_PROT_DEFAULT | PTE_ATTRINDX(MT_DEVICE_nGnRE) | PTE_HYP | PTE_HYP_XN) - #define PAGE_S2_MEMATTR(attr) \ ({ \ u64 __val; \ @@ -79,19 +73,6 @@ extern bool arm64_use_ng_mappings; __val; \ }) -#define PAGE_S2_XN \ - ({ \ - u64 __val; \ - if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC)) \ - __val = 0; \ - else \ - __val = PTE_S2_XN; \ - __val; \ - }) - -#define PAGE_S2 __pgprot(_PROT_DEFAULT | PAGE_S2_MEMATTR(NORMAL) | PTE_S2_RDONLY | PAGE_S2_XN) -#define PAGE_S2_DEVICE __pgprot(_PROT_DEFAULT | PAGE_S2_MEMATTR(DEVICE_nGnRE) | PTE_S2_RDONLY | PTE_S2_XN) - #define PAGE_NONE __pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN) /* shared+writable pages are clean by default, hence PTE_RDONLY|PTE_WRITE */ #define PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE) diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 240fe5e5b720..7d90ea2e2063 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -38,6 +38,7 @@ #include <asm/pgtable-hwdef.h> #include <asm/pointer_auth.h> #include <asm/ptrace.h> +#include <asm/spectre.h> #include <asm/types.h> /* @@ -197,40 +198,15 @@ static inline void start_thread_common(struct pt_regs *regs, unsigned long pc) regs->pmr_save = GIC_PRIO_IRQON; } -static inline void set_ssbs_bit(struct pt_regs *regs) -{ - regs->pstate |= PSR_SSBS_BIT; -} - -static inline void set_compat_ssbs_bit(struct pt_regs *regs) -{ - regs->pstate |= PSR_AA32_SSBS_BIT; -} - static inline void start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) { start_thread_common(regs, pc); regs->pstate = PSR_MODE_EL0t; - - if (arm64_get_ssbd_state() != ARM64_SSBD_FORCE_ENABLE) - set_ssbs_bit(regs); - + spectre_v4_enable_task_mitigation(current); regs->sp = sp; } -static inline bool is_ttbr0_addr(unsigned long addr) -{ - /* entry assembly clears tags for TTBR0 addrs */ - return addr < TASK_SIZE; -} - -static inline bool is_ttbr1_addr(unsigned long addr) -{ - /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ - return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; -} - #ifdef CONFIG_COMPAT static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, unsigned long sp) @@ -244,13 +220,23 @@ static inline void compat_start_thread(struct pt_regs *regs, unsigned long pc, regs->pstate |= PSR_AA32_E_BIT; #endif - if (arm64_get_ssbd_state() != ARM64_SSBD_FORCE_ENABLE) - set_compat_ssbs_bit(regs); - + spectre_v4_enable_task_mitigation(current); regs->compat_sp = sp; } #endif +static inline bool is_ttbr0_addr(unsigned long addr) +{ + /* entry assembly clears tags for TTBR0 addrs */ + return addr < TASK_SIZE; +} + +static inline bool is_ttbr1_addr(unsigned long addr) +{ + /* TTBR1 addresses may have a tag if KASAN_SW_TAGS is in use */ + return arch_kasan_reset_tag(addr) >= PAGE_OFFSET; +} + /* Forward declaration, a strange C thing */ struct task_struct; diff --git a/arch/arm64/include/asm/spectre.h b/arch/arm64/include/asm/spectre.h new file mode 100644 index 000000000000..fcdfbce302bd --- /dev/null +++ b/arch/arm64/include/asm/spectre.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Interface for managing mitigations for Spectre vulnerabilities. + * + * Copyright (C) 2020 Google LLC + * Author: Will Deacon <will@kernel.org> + */ + +#ifndef __ASM_SPECTRE_H +#define __ASM_SPECTRE_H + +#include <asm/cpufeature.h> + +/* Watch out, ordering is important here. */ +enum mitigation_state { + SPECTRE_UNAFFECTED, + SPECTRE_MITIGATED, + SPECTRE_VULNERABLE, +}; + +struct task_struct; + +enum mitigation_state arm64_get_spectre_v2_state(void); +bool has_spectre_v2(const struct arm64_cpu_capabilities *cap, int scope); +void spectre_v2_enable_mitigation(const struct arm64_cpu_capabilities *__unused); + +enum mitigation_state arm64_get_spectre_v4_state(void); +bool has_spectre_v4(const struct arm64_cpu_capabilities *cap, int scope); +void spectre_v4_enable_mitigation(const struct arm64_cpu_capabilities *__unused); +void spectre_v4_enable_task_mitigation(struct task_struct *tsk); + +#endif /* __ASM_SPECTRE_H */ diff --git a/arch/arm64/include/asm/stage2_pgtable.h b/arch/arm64/include/asm/stage2_pgtable.h index 996bf98f0cab..fe341a6578c3 100644 --- a/arch/arm64/include/asm/stage2_pgtable.h +++ b/arch/arm64/include/asm/stage2_pgtable.h @@ -8,7 +8,6 @@ #ifndef __ARM64_S2_PGTABLE_H_ #define __ARM64_S2_PGTABLE_H_ -#include <linux/hugetlb.h> #include <linux/pgtable.h> /* @@ -37,217 +36,12 @@ #define stage2_pgdir_mask(kvm) ~(stage2_pgdir_size(kvm) - 1) /* - * The number of PTRS across all concatenated stage2 tables given by the - * number of bits resolved at the initial level. - * If we force more levels than necessary, we may have (stage2_pgdir_shift > IPA), - * in which case, stage2_pgd_ptrs will have one entry. - */ -#define pgd_ptrs_shift(ipa, pgdir_shift) \ - ((ipa) > (pgdir_shift) ? ((ipa) - (pgdir_shift)) : 0) -#define __s2_pgd_ptrs(ipa, lvls) \ - (1 << (pgd_ptrs_shift((ipa), pt_levels_pgdir_shift(lvls)))) -#define __s2_pgd_size(ipa, lvls) (__s2_pgd_ptrs((ipa), (lvls)) * sizeof(pgd_t)) - -#define stage2_pgd_ptrs(kvm) __s2_pgd_ptrs(kvm_phys_shift(kvm), kvm_stage2_levels(kvm)) -#define stage2_pgd_size(kvm) __s2_pgd_size(kvm_phys_shift(kvm), kvm_stage2_levels(kvm)) - -/* * kvm_mmmu_cache_min_pages() is the number of pages required to install * a stage-2 translation. We pre-allocate the entry level page table at * the VM creation. */ #define kvm_mmu_cache_min_pages(kvm) (kvm_stage2_levels(kvm) - 1) -/* Stage2 PUD definitions when the level is present */ -static inline bool kvm_stage2_has_pud(struct kvm *kvm) -{ - return (CONFIG_PGTABLE_LEVELS > 3) && (kvm_stage2_levels(kvm) > 3); -} - -#define S2_PUD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(1) -#define S2_PUD_SIZE (1UL << S2_PUD_SHIFT) -#define S2_PUD_MASK (~(S2_PUD_SIZE - 1)) - -#define stage2_pgd_none(kvm, pgd) pgd_none(pgd) -#define stage2_pgd_clear(kvm, pgd) pgd_clear(pgd) -#define stage2_pgd_present(kvm, pgd) pgd_present(pgd) -#define stage2_pgd_populate(kvm, pgd, p4d) pgd_populate(NULL, pgd, p4d) - -static inline p4d_t *stage2_p4d_offset(struct kvm *kvm, - pgd_t *pgd, unsigned long address) -{ - return p4d_offset(pgd, address); -} - -static inline void stage2_p4d_free(struct kvm *kvm, p4d_t *p4d) -{ -} - -static inline bool stage2_p4d_table_empty(struct kvm *kvm, p4d_t *p4dp) -{ - return false; -} - -static inline phys_addr_t stage2_p4d_addr_end(struct kvm *kvm, - phys_addr_t addr, phys_addr_t end) -{ - return end; -} - -static inline bool stage2_p4d_none(struct kvm *kvm, p4d_t p4d) -{ - if (kvm_stage2_has_pud(kvm)) - return p4d_none(p4d); - else - return 0; -} - -static inline void stage2_p4d_clear(struct kvm *kvm, p4d_t *p4dp) -{ - if (kvm_stage2_has_pud(kvm)) - p4d_clear(p4dp); -} - -static inline bool stage2_p4d_present(struct kvm *kvm, p4d_t p4d) -{ - if (kvm_stage2_has_pud(kvm)) - return p4d_present(p4d); - else - return 1; -} - -static inline void stage2_p4d_populate(struct kvm *kvm, p4d_t *p4d, pud_t *pud) -{ - if (kvm_stage2_has_pud(kvm)) - p4d_populate(NULL, p4d, pud); -} - -static inline pud_t *stage2_pud_offset(struct kvm *kvm, - p4d_t *p4d, unsigned long address) -{ - if (kvm_stage2_has_pud(kvm)) - return pud_offset(p4d, address); - else - return (pud_t *)p4d; -} - -static inline void stage2_pud_free(struct kvm *kvm, pud_t *pud) -{ - if (kvm_stage2_has_pud(kvm)) - free_page((unsigned long)pud); -} - -static inline bool stage2_pud_table_empty(struct kvm *kvm, pud_t *pudp) -{ - if (kvm_stage2_has_pud(kvm)) - return kvm_page_empty(pudp); - else - return false; -} - -static inline phys_addr_t -stage2_pud_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) -{ - if (kvm_stage2_has_pud(kvm)) { - phys_addr_t boundary = (addr + S2_PUD_SIZE) & S2_PUD_MASK; - - return (boundary - 1 < end - 1) ? boundary : end; - } else { - return end; - } -} - -/* Stage2 PMD definitions when the level is present */ -static inline bool kvm_stage2_has_pmd(struct kvm *kvm) -{ - return (CONFIG_PGTABLE_LEVELS > 2) && (kvm_stage2_levels(kvm) > 2); -} - -#define S2_PMD_SHIFT ARM64_HW_PGTABLE_LEVEL_SHIFT(2) -#define S2_PMD_SIZE (1UL << S2_PMD_SHIFT) -#define S2_PMD_MASK (~(S2_PMD_SIZE - 1)) - -static inline bool stage2_pud_none(struct kvm *kvm, pud_t pud) -{ - if (kvm_stage2_has_pmd(kvm)) - return pud_none(pud); - else - return 0; -} - -static inline void stage2_pud_clear(struct kvm *kvm, pud_t *pud) -{ - if (kvm_stage2_has_pmd(kvm)) - pud_clear(pud); -} - -static inline bool stage2_pud_present(struct kvm *kvm, pud_t pud) -{ - if (kvm_stage2_has_pmd(kvm)) - return pud_present(pud); - else - return 1; -} - -static inline void stage2_pud_populate(struct kvm *kvm, pud_t *pud, pmd_t *pmd) -{ - if (kvm_stage2_has_pmd(kvm)) - pud_populate(NULL, pud, pmd); -} - -static inline pmd_t *stage2_pmd_offset(struct kvm *kvm, - pud_t *pud, unsigned long address) -{ - if (kvm_stage2_has_pmd(kvm)) - return pmd_offset(pud, address); - else - return (pmd_t *)pud; -} - -static inline void stage2_pmd_free(struct kvm *kvm, pmd_t *pmd) -{ - if (kvm_stage2_has_pmd(kvm)) - free_page((unsigned long)pmd); -} - -static inline bool stage2_pud_huge(struct kvm *kvm, pud_t pud) -{ - if (kvm_stage2_has_pmd(kvm)) - return pud_huge(pud); - else - return 0; -} - -static inline bool stage2_pmd_table_empty(struct kvm *kvm, pmd_t *pmdp) -{ - if (kvm_stage2_has_pmd(kvm)) - return kvm_page_empty(pmdp); - else - return 0; -} - -static inline phys_addr_t -stage2_pmd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) -{ - if (kvm_stage2_has_pmd(kvm)) { - phys_addr_t boundary = (addr + S2_PMD_SIZE) & S2_PMD_MASK; - - return (boundary - 1 < end - 1) ? boundary : end; - } else { - return end; - } -} - -static inline bool stage2_pte_table_empty(struct kvm *kvm, pte_t *ptep) -{ - return kvm_page_empty(ptep); -} - -static inline unsigned long stage2_pgd_index(struct kvm *kvm, phys_addr_t addr) -{ - return (((addr) >> stage2_pgdir_shift(kvm)) & (stage2_pgd_ptrs(kvm) - 1)); -} - static inline phys_addr_t stage2_pgd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) { @@ -256,13 +50,4 @@ stage2_pgd_addr_end(struct kvm *kvm, phys_addr_t addr, phys_addr_t end) return (boundary - 1 < end - 1) ? boundary : end; } -/* - * Level values for the ARMv8.4-TTL extension, mapping PUD/PMD/PTE and - * the architectural page-table level. - */ -#define S2_NO_LEVEL_HINT 0 -#define S2_PUD_LEVEL 1 -#define S2_PMD_LEVEL 2 -#define S2_PTE_LEVEL 3 - #endif /* __ARM64_S2_PGTABLE_H_ */ diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h index ba85bb23f060..1c17c3a24411 100644 --- a/arch/arm64/include/uapi/asm/kvm.h +++ b/arch/arm64/include/uapi/asm/kvm.h @@ -159,6 +159,21 @@ struct kvm_sync_regs { struct kvm_arch_memory_slot { }; +/* + * PMU filter structure. Describe a range of events with a particular + * action. To be used with KVM_ARM_VCPU_PMU_V3_FILTER. + */ +struct kvm_pmu_event_filter { + __u16 base_event; + __u16 nevents; + +#define KVM_PMU_EVENT_ALLOW 0 +#define KVM_PMU_EVENT_DENY 1 + + __u8 action; + __u8 pad[3]; +}; + /* for KVM_GET/SET_VCPU_EVENTS */ struct kvm_vcpu_events { struct { @@ -242,6 +257,15 @@ struct kvm_vcpu_events { #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL 0 #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL 1 #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_REQUIRED 2 + +/* + * Only two states can be presented by the host kernel: + * - NOT_REQUIRED: the guest doesn't need to do anything + * - NOT_AVAIL: the guest isn't mitigated (it can still use SSBS if available) + * + * All the other values are deprecated. The host still accepts all + * values (they are ABI), but will narrow them to the above two. + */ #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2 KVM_REG_ARM_FW_REG(2) #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL 0 #define KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNKNOWN 1 @@ -329,6 +353,7 @@ struct kvm_vcpu_events { #define KVM_ARM_VCPU_PMU_V3_CTRL 0 #define KVM_ARM_VCPU_PMU_V3_IRQ 0 #define KVM_ARM_VCPU_PMU_V3_INIT 1 +#define KVM_ARM_VCPU_PMU_V3_FILTER 2 #define KVM_ARM_VCPU_TIMER_CTRL 1 #define KVM_ARM_VCPU_TIMER_IRQ_VTIMER 0 #define KVM_ARM_VCPU_TIMER_IRQ_PTIMER 1 diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile index a561cbb91d4d..bd12b9a2ab4a 100644 --- a/arch/arm64/kernel/Makefile +++ b/arch/arm64/kernel/Makefile @@ -19,7 +19,7 @@ obj-y := debug-monitors.o entry.o irq.o fpsimd.o \ return_address.o cpuinfo.o cpu_errata.o \ cpufeature.o alternative.o cacheinfo.o \ smp.o smp_spin_table.o topology.o smccc-call.o \ - syscall.o + syscall.o proton-pack.o targets += efi-entry.o @@ -59,7 +59,6 @@ arm64-reloc-test-y := reloc_test_core.o reloc_test_syms.o obj-$(CONFIG_CRASH_DUMP) += crash_dump.o obj-$(CONFIG_CRASH_CORE) += crash_core.o obj-$(CONFIG_ARM_SDE_INTERFACE) += sdei.o -obj-$(CONFIG_ARM64_SSBD) += ssbd.o obj-$(CONFIG_ARM64_PTR_AUTH) += pointer_auth.o obj-$(CONFIG_SHADOW_CALL_STACK) += scs.o diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index c332d49780dc..6c8303559beb 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -106,365 +106,6 @@ cpu_enable_trap_ctr_access(const struct arm64_cpu_capabilities *cap) sysreg_clear_set(sctlr_el1, SCTLR_EL1_UCT, 0); } -atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1); - -#include <asm/mmu_context.h> -#include <asm/cacheflush.h> - -DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); - -#ifdef CONFIG_KVM_INDIRECT_VECTORS -static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start, - const char *hyp_vecs_end) -{ - void *dst = lm_alias(__bp_harden_hyp_vecs + slot * SZ_2K); - int i; - - for (i = 0; i < SZ_2K; i += 0x80) - memcpy(dst + i, hyp_vecs_start, hyp_vecs_end - hyp_vecs_start); - - __flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K); -} - -static void install_bp_hardening_cb(bp_hardening_cb_t fn, - const char *hyp_vecs_start, - const char *hyp_vecs_end) -{ - static DEFINE_RAW_SPINLOCK(bp_lock); - int cpu, slot = -1; - - /* - * detect_harden_bp_fw() passes NULL for the hyp_vecs start/end if - * we're a guest. Skip the hyp-vectors work. - */ - if (!hyp_vecs_start) { - __this_cpu_write(bp_hardening_data.fn, fn); - return; - } - - raw_spin_lock(&bp_lock); - for_each_possible_cpu(cpu) { - if (per_cpu(bp_hardening_data.fn, cpu) == fn) { - slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu); - break; - } - } - - if (slot == -1) { - slot = atomic_inc_return(&arm64_el2_vector_last_slot); - BUG_ON(slot >= BP_HARDEN_EL2_SLOTS); - __copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end); - } - - __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot); - __this_cpu_write(bp_hardening_data.fn, fn); - raw_spin_unlock(&bp_lock); -} -#else -static void install_bp_hardening_cb(bp_hardening_cb_t fn, - const char *hyp_vecs_start, - const char *hyp_vecs_end) -{ - __this_cpu_write(bp_hardening_data.fn, fn); -} -#endif /* CONFIG_KVM_INDIRECT_VECTORS */ - -#include <linux/arm-smccc.h> - -static void __maybe_unused call_smc_arch_workaround_1(void) -{ - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); -} - -static void call_hvc_arch_workaround_1(void) -{ - arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); -} - -static void qcom_link_stack_sanitization(void) -{ - u64 tmp; - - asm volatile("mov %0, x30 \n" - ".rept 16 \n" - "bl . + 4 \n" - ".endr \n" - "mov x30, %0 \n" - : "=&r" (tmp)); -} - -static bool __nospectre_v2; -static int __init parse_nospectre_v2(char *str) -{ - __nospectre_v2 = true; - return 0; -} -early_param("nospectre_v2", parse_nospectre_v2); - -/* - * -1: No workaround - * 0: No workaround required - * 1: Workaround installed - */ -static int detect_harden_bp_fw(void) -{ - bp_hardening_cb_t cb; - void *smccc_start, *smccc_end; - struct arm_smccc_res res; - u32 midr = read_cpuid_id(); - - arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, - ARM_SMCCC_ARCH_WORKAROUND_1, &res); - - switch ((int)res.a0) { - case 1: - /* Firmware says we're just fine */ - return 0; - case 0: - break; - default: - return -1; - } - - switch (arm_smccc_1_1_get_conduit()) { - case SMCCC_CONDUIT_HVC: - cb = call_hvc_arch_workaround_1; - /* This is a guest, no need to patch KVM vectors */ - smccc_start = NULL; - smccc_end = NULL; - break; - -#if IS_ENABLED(CONFIG_KVM) - case SMCCC_CONDUIT_SMC: - cb = call_smc_arch_workaround_1; - smccc_start = __smccc_workaround_1_smc; - smccc_end = __smccc_workaround_1_smc + - __SMCCC_WORKAROUND_1_SMC_SZ; - break; -#endif - - default: - return -1; - } - - if (((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR) || - ((midr & MIDR_CPU_MODEL_MASK) == MIDR_QCOM_FALKOR_V1)) - cb = qcom_link_stack_sanitization; - - if (IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR)) - install_bp_hardening_cb(cb, smccc_start, smccc_end); - - return 1; -} - -DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required); - -int ssbd_state __read_mostly = ARM64_SSBD_KERNEL; -static bool __ssb_safe = true; - -static const struct ssbd_options { - const char *str; - int state; -} ssbd_options[] = { - { "force-on", ARM64_SSBD_FORCE_ENABLE, }, - { "force-off", ARM64_SSBD_FORCE_DISABLE, }, - { "kernel", ARM64_SSBD_KERNEL, }, -}; - -static int __init ssbd_cfg(char *buf) -{ - int i; - - if (!buf || !buf[0]) - return -EINVAL; - - for (i = 0; i < ARRAY_SIZE(ssbd_options); i++) { - int len = strlen(ssbd_options[i].str); - - if (strncmp(buf, ssbd_options[i].str, len)) - continue; - - ssbd_state = ssbd_options[i].state; - return 0; - } - - return -EINVAL; -} -early_param("ssbd", ssbd_cfg); - -void __init arm64_update_smccc_conduit(struct alt_instr *alt, - __le32 *origptr, __le32 *updptr, - int nr_inst) -{ - u32 insn; - - BUG_ON(nr_inst != 1); - - switch (arm_smccc_1_1_get_conduit()) { - case SMCCC_CONDUIT_HVC: - insn = aarch64_insn_get_hvc_value(); - break; - case SMCCC_CONDUIT_SMC: - insn = aarch64_insn_get_smc_value(); - break; - default: - return; - } - - *updptr = cpu_to_le32(insn); -} - -void __init arm64_enable_wa2_handling(struct alt_instr *alt, - __le32 *origptr, __le32 *updptr, - int nr_inst) -{ - BUG_ON(nr_inst != 1); - /* - * Only allow mitigation on EL1 entry/exit and guest - * ARCH_WORKAROUND_2 handling if the SSBD state allows it to - * be flipped. - */ - if (arm64_get_ssbd_state() == ARM64_SSBD_KERNEL) - *updptr = cpu_to_le32(aarch64_insn_gen_nop()); -} - -void arm64_set_ssbd_mitigation(bool state) -{ - int conduit; - - if (!IS_ENABLED(CONFIG_ARM64_SSBD)) { - pr_info_once("SSBD disabled by kernel configuration\n"); - return; - } - - if (this_cpu_has_cap(ARM64_SSBS)) { - if (state) - asm volatile(SET_PSTATE_SSBS(0)); - else - asm volatile(SET_PSTATE_SSBS(1)); - return; - } - - conduit = arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_WORKAROUND_2, state, - NULL); - - WARN_ON_ONCE(conduit == SMCCC_CONDUIT_NONE); -} - -static bool has_ssbd_mitigation(const struct arm64_cpu_capabilities *entry, - int scope) -{ - struct arm_smccc_res res; - bool required = true; - s32 val; - bool this_cpu_safe = false; - int conduit; - - WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); - - if (cpu_mitigations_off()) - ssbd_state = ARM64_SSBD_FORCE_DISABLE; - - /* delay setting __ssb_safe until we get a firmware response */ - if (is_midr_in_range_list(read_cpuid_id(), entry->midr_range_list)) - this_cpu_safe = true; - - if (this_cpu_has_cap(ARM64_SSBS)) { - if (!this_cpu_safe) - __ssb_safe = false; - required = false; - goto out_printmsg; - } - - conduit = arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, - ARM_SMCCC_ARCH_WORKAROUND_2, &res); - - if (conduit == SMCCC_CONDUIT_NONE) { - ssbd_state = ARM64_SSBD_UNKNOWN; - if (!this_cpu_safe) - __ssb_safe = false; - return false; - } - - val = (s32)res.a0; - - switch (val) { - case SMCCC_RET_NOT_SUPPORTED: - ssbd_state = ARM64_SSBD_UNKNOWN; - if (!this_cpu_safe) - __ssb_safe = false; - return false; - - /* machines with mixed mitigation requirements must not return this */ - case SMCCC_RET_NOT_REQUIRED: - pr_info_once("%s mitigation not required\n", entry->desc); - ssbd_state = ARM64_SSBD_MITIGATED; - return false; - - case SMCCC_RET_SUCCESS: - __ssb_safe = false; - required = true; - break; - - case 1: /* Mitigation not required on this CPU */ - required = false; - break; - - default: - WARN_ON(1); - if (!this_cpu_safe) - __ssb_safe = false; - return false; - } - - switch (ssbd_state) { - case ARM64_SSBD_FORCE_DISABLE: - arm64_set_ssbd_mitigation(false); - required = false; - break; - - case ARM64_SSBD_KERNEL: - if (required) { - __this_cpu_write(arm64_ssbd_callback_required, 1); - arm64_set_ssbd_mitigation(true); - } - break; - - case ARM64_SSBD_FORCE_ENABLE: - arm64_set_ssbd_mitigation(true); - required = true; - break; - - default: - WARN_ON(1); - break; - } - -out_printmsg: - switch (ssbd_state) { - case ARM64_SSBD_FORCE_DISABLE: - pr_info_once("%s disabled from command-line\n", entry->desc); - break; - - case ARM64_SSBD_FORCE_ENABLE: - pr_info_once("%s forced from command-line\n", entry->desc); - break; - } - - return required; -} - -/* known invulnerable cores */ -static const struct midr_range arm64_ssb_cpus[] = { - MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), - MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53), - MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER), - MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER), - {}, -}; - #ifdef CONFIG_ARM64_ERRATUM_1463225 DEFINE_PER_CPU(int, __in_cortex_a76_erratum_1463225_wa); @@ -519,83 +160,6 @@ cpu_enable_cache_maint_trap(const struct arm64_cpu_capabilities *__unused) .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, \ CAP_MIDR_RANGE_LIST(midr_list) -/* Track overall mitigation state. We are only mitigated if all cores are ok */ -static bool __hardenbp_enab = true; -static bool __spectrev2_safe = true; - -int get_spectre_v2_workaround_state(void) -{ - if (__spectrev2_safe) - return ARM64_BP_HARDEN_NOT_REQUIRED; - - if (!__hardenbp_enab) - return ARM64_BP_HARDEN_UNKNOWN; - - return ARM64_BP_HARDEN_WA_NEEDED; -} - -/* - * List of CPUs that do not need any Spectre-v2 mitigation at all. - */ -static const struct midr_range spectre_v2_safe_list[] = { - MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), - MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), - MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53), - MIDR_ALL_VERSIONS(MIDR_HISI_TSV110), - MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER), - MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER), - { /* sentinel */ } -}; - -/* - * Track overall bp hardening for all heterogeneous cores in the machine. - * We are only considered "safe" if all booted cores are known safe. - */ -static bool __maybe_unused -check_branch_predictor(const struct arm64_cpu_capabilities *entry, int scope) -{ - int need_wa; - - WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); - - /* If the CPU has CSV2 set, we're safe */ - if (cpuid_feature_extract_unsigned_field(read_cpuid(ID_AA64PFR0_EL1), - ID_AA64PFR0_CSV2_SHIFT)) - return false; - - /* Alternatively, we have a list of unaffected CPUs */ - if (is_midr_in_range_list(read_cpuid_id(), spectre_v2_safe_list)) - return false; - - /* Fallback to firmware detection */ - need_wa = detect_harden_bp_fw(); - if (!need_wa) - return false; - - __spectrev2_safe = false; - - if (!IS_ENABLED(CONFIG_HARDEN_BRANCH_PREDICTOR)) { - pr_warn_once("spectrev2 mitigation disabled by kernel configuration\n"); - __hardenbp_enab = false; - return false; - } - - /* forced off */ - if (__nospectre_v2 || cpu_mitigations_off()) { - pr_info_once("spectrev2 mitigation disabled by command line option\n"); - __hardenbp_enab = false; - return false; - } - - if (need_wa < 0) { - pr_warn_once("ARM_SMCCC_ARCH_WORKAROUND_1 missing from firmware\n"); - __hardenbp_enab = false; - } - - return (need_wa > 0); -} - static const __maybe_unused struct midr_range tx2_family_cpus[] = { MIDR_ALL_VERSIONS(MIDR_BRCM_VULCAN), MIDR_ALL_VERSIONS(MIDR_CAVIUM_THUNDERX2), @@ -887,9 +451,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = { }, #endif { - .capability = ARM64_HARDEN_BRANCH_PREDICTOR, + .desc = "Spectre-v2", + .capability = ARM64_SPECTRE_V2, .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, - .matches = check_branch_predictor, + .matches = has_spectre_v2, + .cpu_enable = spectre_v2_enable_mitigation, }, #ifdef CONFIG_RANDOMIZE_BASE { @@ -899,11 +465,11 @@ const struct arm64_cpu_capabilities arm64_errata[] = { }, #endif { - .desc = "Speculative Store Bypass Disable", - .capability = ARM64_SSBD, + .desc = "Spectre-v4", + .capability = ARM64_SPECTRE_V4, .type = ARM64_CPUCAP_LOCAL_CPU_ERRATUM, - .matches = has_ssbd_mitigation, - .midr_range_list = arm64_ssb_cpus, + .matches = has_spectre_v4, + .cpu_enable = spectre_v4_enable_mitigation, }, #ifdef CONFIG_ARM64_ERRATUM_1418040 { @@ -956,40 +522,3 @@ const struct arm64_cpu_capabilities arm64_errata[] = { { } }; - -ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, - char *buf) -{ - return sprintf(buf, "Mitigation: __user pointer sanitization\n"); -} - -ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, - char *buf) -{ - switch (get_spectre_v2_workaround_state()) { - case ARM64_BP_HARDEN_NOT_REQUIRED: - return sprintf(buf, "Not affected\n"); - case ARM64_BP_HARDEN_WA_NEEDED: - return sprintf(buf, "Mitigation: Branch predictor hardening\n"); - case ARM64_BP_HARDEN_UNKNOWN: - default: - return sprintf(buf, "Vulnerable\n"); - } -} - -ssize_t cpu_show_spec_store_bypass(struct device *dev, - struct device_attribute *attr, char *buf) -{ - if (__ssb_safe) - return sprintf(buf, "Not affected\n"); - - switch (ssbd_state) { - case ARM64_SSBD_KERNEL: - case ARM64_SSBD_FORCE_ENABLE: - if (IS_ENABLED(CONFIG_ARM64_SSBD)) - return sprintf(buf, - "Mitigation: Speculative Store Bypass disabled via prctl\n"); - } - - return sprintf(buf, "Vulnerable\n"); -} diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 6424584be01e..a4debb63ebfb 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -227,7 +227,7 @@ static const struct arm64_ftr_bits ftr_id_aa64pfr0[] = { static const struct arm64_ftr_bits ftr_id_aa64pfr1[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_MPAMFRAC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_RASFRAC_SHIFT, 4, 0), - ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI), + ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64PFR1_SSBS_SHIFT, 4, ID_AA64PFR1_SSBS_PSTATE_NI), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_BTI), FTR_STRICT, FTR_LOWER_SAFE, ID_AA64PFR1_BT_SHIFT, 4, 0), ARM64_FTR_END, @@ -487,7 +487,7 @@ static const struct arm64_ftr_bits ftr_id_pfr1[] = { }; static const struct arm64_ftr_bits ftr_id_pfr2[] = { - ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0), ARM64_FTR_END, }; @@ -1583,48 +1583,6 @@ static void cpu_has_fwb(const struct arm64_cpu_capabilities *__unused) WARN_ON(val & (7 << 27 | 7 << 21)); } -#ifdef CONFIG_ARM64_SSBD -static int ssbs_emulation_handler(struct pt_regs *regs, u32 instr) -{ - if (user_mode(regs)) - return 1; - - if (instr & BIT(PSTATE_Imm_shift)) - regs->pstate |= PSR_SSBS_BIT; - else - regs->pstate &= ~PSR_SSBS_BIT; - - arm64_skip_faulting_instruction(regs, 4); - return 0; -} - -static struct undef_hook ssbs_emulation_hook = { - .instr_mask = ~(1U << PSTATE_Imm_shift), - .instr_val = 0xd500401f | PSTATE_SSBS, - .fn = ssbs_emulation_handler, -}; - -static void cpu_enable_ssbs(const struct arm64_cpu_capabilities *__unused) -{ - static bool undef_hook_registered = false; - static DEFINE_RAW_SPINLOCK(hook_lock); - - raw_spin_lock(&hook_lock); - if (!undef_hook_registered) { - register_undef_hook(&ssbs_emulation_hook); - undef_hook_registered = true; - } - raw_spin_unlock(&hook_lock); - - if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) { - sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_DSSBS); - arm64_set_ssbd_mitigation(false); - } else { - arm64_set_ssbd_mitigation(true); - } -} -#endif /* CONFIG_ARM64_SSBD */ - #ifdef CONFIG_ARM64_PAN static void cpu_enable_pan(const struct arm64_cpu_capabilities *__unused) { @@ -1976,19 +1934,16 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .field_pos = ID_AA64ISAR0_CRC32_SHIFT, .min_field_value = 1, }, -#ifdef CONFIG_ARM64_SSBD { .desc = "Speculative Store Bypassing Safe (SSBS)", .capability = ARM64_SSBS, - .type = ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE, + .type = ARM64_CPUCAP_SYSTEM_FEATURE, .matches = has_cpuid_feature, .sys_reg = SYS_ID_AA64PFR1_EL1, .field_pos = ID_AA64PFR1_SSBS_SHIFT, .sign = FTR_UNSIGNED, .min_field_value = ID_AA64PFR1_SSBS_PSTATE_ONLY, - .cpu_enable = cpu_enable_ssbs, }, -#endif #ifdef CONFIG_ARM64_CNP { .desc = "Common not Private translations", diff --git a/arch/arm64/kernel/entry.S b/arch/arm64/kernel/entry.S index 55af8b504b65..aeb337029d56 100644 --- a/arch/arm64/kernel/entry.S +++ b/arch/arm64/kernel/entry.S @@ -132,9 +132,8 @@ alternative_else_nop_endif * them if required. */ .macro apply_ssbd, state, tmp1, tmp2 -#ifdef CONFIG_ARM64_SSBD -alternative_cb arm64_enable_wa2_handling - b .L__asm_ssbd_skip\@ +alternative_cb spectre_v4_patch_fw_mitigation_enable + b .L__asm_ssbd_skip\@ // Patched to NOP alternative_cb_end ldr_this_cpu \tmp2, arm64_ssbd_callback_required, \tmp1 cbz \tmp2, .L__asm_ssbd_skip\@ @@ -142,11 +141,10 @@ alternative_cb_end tbnz \tmp2, #TIF_SSBD, .L__asm_ssbd_skip\@ mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2 mov w1, #\state -alternative_cb arm64_update_smccc_conduit +alternative_cb spectre_v4_patch_fw_mitigation_conduit nop // Patched to SMC/HVC #0 alternative_cb_end .L__asm_ssbd_skip\@: -#endif .endm .macro kernel_entry, el, regsize = 64 @@ -697,11 +695,9 @@ el0_irq_naked: bl trace_hardirqs_off #endif -#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR tbz x22, #55, 1f bl do_el0_irq_bp_hardening 1: -#endif irq_handler #ifdef CONFIG_TRACE_IRQFLAGS diff --git a/arch/arm64/kernel/hibernate.c b/arch/arm64/kernel/hibernate.c index 68e14152d6e9..c7b00120dc3e 100644 --- a/arch/arm64/kernel/hibernate.c +++ b/arch/arm64/kernel/hibernate.c @@ -332,11 +332,7 @@ int swsusp_arch_suspend(void) * mitigation off behind our back, let's set the state * to what we expect it to be. */ - switch (arm64_get_ssbd_state()) { - case ARM64_SSBD_FORCE_ENABLE: - case ARM64_SSBD_KERNEL: - arm64_set_ssbd_mitigation(true); - } + spectre_v4_enable_mitigation(NULL); } local_daif_restore(flags); diff --git a/arch/arm64/kernel/image-vars.h b/arch/arm64/kernel/image-vars.h index 8982b68289b7..fbd4b6b1fde5 100644 --- a/arch/arm64/kernel/image-vars.h +++ b/arch/arm64/kernel/image-vars.h @@ -61,16 +61,11 @@ __efistub__ctype = _ctype; * memory mappings. */ -#define KVM_NVHE_ALIAS(sym) __kvm_nvhe_##sym = sym; - /* Alternative callbacks for init-time patching of nVHE hyp code. */ -KVM_NVHE_ALIAS(arm64_enable_wa2_handling); KVM_NVHE_ALIAS(kvm_patch_vector_branch); KVM_NVHE_ALIAS(kvm_update_va_mask); /* Global kernel state accessed by nVHE hyp code. */ -KVM_NVHE_ALIAS(arm64_ssbd_callback_required); -KVM_NVHE_ALIAS(kvm_host_data); KVM_NVHE_ALIAS(kvm_vgic_global_state); /* Kernel constant needed to compute idmap addresses. */ diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index f1804496b935..085d8ca39e47 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -21,6 +21,7 @@ #include <linux/lockdep.h> #include <linux/mman.h> #include <linux/mm.h> +#include <linux/nospec.h> #include <linux/stddef.h> #include <linux/sysctl.h> #include <linux/unistd.h> @@ -421,8 +422,7 @@ int copy_thread(unsigned long clone_flags, unsigned long stack_start, cpus_have_const_cap(ARM64_HAS_UAO)) childregs->pstate |= PSR_UAO_BIT; - if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) - set_ssbs_bit(childregs); + spectre_v4_enable_task_mitigation(p); if (system_uses_irq_prio_masking()) childregs->pmr_save = GIC_PRIO_IRQON; @@ -472,8 +472,6 @@ void uao_thread_switch(struct task_struct *next) */ static void ssbs_thread_switch(struct task_struct *next) { - struct pt_regs *regs = task_pt_regs(next); - /* * Nothing to do for kernel threads, but 'regs' may be junk * (e.g. idle task) so check the flags and bail early. @@ -485,18 +483,10 @@ static void ssbs_thread_switch(struct task_struct *next) * If all CPUs implement the SSBS extension, then we just need to * context-switch the PSTATE field. */ - if (cpu_have_feature(cpu_feature(SSBS))) - return; - - /* If the mitigation is enabled, then we leave SSBS clear. */ - if ((arm64_get_ssbd_state() == ARM64_SSBD_FORCE_ENABLE) || - test_tsk_thread_flag(next, TIF_SSBD)) + if (cpus_have_const_cap(ARM64_SSBS)) return; - if (compat_user_mode(regs)) - set_compat_ssbs_bit(regs); - else if (user_mode(regs)) - set_ssbs_bit(regs); + spectre_v4_enable_task_mitigation(next); } /* @@ -620,6 +610,11 @@ void arch_setup_new_exec(void) current->mm->context.flags = is_compat_task() ? MMCF_AARCH32 : 0; ptrauth_thread_init_user(current); + + if (task_spec_ssb_noexec(current)) { + arch_prctl_spec_ctrl_set(current, PR_SPEC_STORE_BYPASS, + PR_SPEC_ENABLE); + } } #ifdef CONFIG_ARM64_TAGGED_ADDR_ABI diff --git a/arch/arm64/kernel/proton-pack.c b/arch/arm64/kernel/proton-pack.c new file mode 100644 index 000000000000..68b710f1b43f --- /dev/null +++ b/arch/arm64/kernel/proton-pack.c @@ -0,0 +1,792 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Handle detection, reporting and mitigation of Spectre v1, v2 and v4, as + * detailed at: + * + * https://developer.arm.com/support/arm-security-updates/speculative-processor-vulnerability + * + * This code was originally written hastily under an awful lot of stress and so + * aspects of it are somewhat hacky. Unfortunately, changing anything in here + * instantly makes me feel ill. Thanks, Jann. Thann. + * + * Copyright (C) 2018 ARM Ltd, All Rights Reserved. + * Copyright (C) 2020 Google LLC + * + * "If there's something strange in your neighbourhood, who you gonna call?" + * + * Authors: Will Deacon <will@kernel.org> and Marc Zyngier <maz@kernel.org> + */ + +#include <linux/arm-smccc.h> +#include <linux/cpu.h> +#include <linux/device.h> +#include <linux/nospec.h> +#include <linux/prctl.h> +#include <linux/sched/task_stack.h> + +#include <asm/spectre.h> +#include <asm/traps.h> + +/* + * We try to ensure that the mitigation state can never change as the result of + * onlining a late CPU. + */ +static void update_mitigation_state(enum mitigation_state *oldp, + enum mitigation_state new) +{ + enum mitigation_state state; + + do { + state = READ_ONCE(*oldp); + if (new <= state) + break; + + /* Userspace almost certainly can't deal with this. */ + if (WARN_ON(system_capabilities_finalized())) + break; + } while (cmpxchg_relaxed(oldp, state, new) != state); +} + +/* + * Spectre v1. + * + * The kernel can't protect userspace for this one: it's each person for + * themselves. Advertise what we're doing and be done with it. + */ +ssize_t cpu_show_spectre_v1(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "Mitigation: __user pointer sanitization\n"); +} + +/* + * Spectre v2. + * + * This one sucks. A CPU is either: + * + * - Mitigated in hardware and advertised by ID_AA64PFR0_EL1.CSV2. + * - Mitigated in hardware and listed in our "safe list". + * - Mitigated in software by firmware. + * - Mitigated in software by a CPU-specific dance in the kernel. + * - Vulnerable. + * + * It's not unlikely for different CPUs in a big.LITTLE system to fall into + * different camps. + */ +static enum mitigation_state spectre_v2_state; + +static bool __read_mostly __nospectre_v2; +static int __init parse_spectre_v2_param(char *str) +{ + __nospectre_v2 = true; + return 0; +} +early_param("nospectre_v2", parse_spectre_v2_param); + +static bool spectre_v2_mitigations_off(void) +{ + bool ret = __nospectre_v2 || cpu_mitigations_off(); + + if (ret) + pr_info_once("spectre-v2 mitigation disabled by command line option\n"); + + return ret; +} + +ssize_t cpu_show_spectre_v2(struct device *dev, struct device_attribute *attr, + char *buf) +{ + switch (spectre_v2_state) { + case SPECTRE_UNAFFECTED: + return sprintf(buf, "Not affected\n"); + case SPECTRE_MITIGATED: + return sprintf(buf, "Mitigation: Branch predictor hardening\n"); + case SPECTRE_VULNERABLE: + fallthrough; + default: + return sprintf(buf, "Vulnerable\n"); + } +} + +static enum mitigation_state spectre_v2_get_cpu_hw_mitigation_state(void) +{ + u64 pfr0; + static const struct midr_range spectre_v2_safe_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), + MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53), + MIDR_ALL_VERSIONS(MIDR_HISI_TSV110), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER), + { /* sentinel */ } + }; + + /* If the CPU has CSV2 set, we're safe */ + pfr0 = read_cpuid(ID_AA64PFR0_EL1); + if (cpuid_feature_extract_unsigned_field(pfr0, ID_AA64PFR0_CSV2_SHIFT)) + return SPECTRE_UNAFFECTED; + + /* Alternatively, we have a list of unaffected CPUs */ + if (is_midr_in_range_list(read_cpuid_id(), spectre_v2_safe_list)) + return SPECTRE_UNAFFECTED; + + return SPECTRE_VULNERABLE; +} + +#define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED (1) + +static enum mitigation_state spectre_v2_get_cpu_fw_mitigation_state(void) +{ + int ret; + struct arm_smccc_res res; + + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_1, &res); + + ret = res.a0; + switch (ret) { + case SMCCC_RET_SUCCESS: + return SPECTRE_MITIGATED; + case SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED: + return SPECTRE_UNAFFECTED; + default: + fallthrough; + case SMCCC_RET_NOT_SUPPORTED: + return SPECTRE_VULNERABLE; + } +} + +bool has_spectre_v2(const struct arm64_cpu_capabilities *entry, int scope) +{ + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + + if (spectre_v2_get_cpu_hw_mitigation_state() == SPECTRE_UNAFFECTED) + return false; + + if (spectre_v2_get_cpu_fw_mitigation_state() == SPECTRE_UNAFFECTED) + return false; + + return true; +} + +DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data); + +enum mitigation_state arm64_get_spectre_v2_state(void) +{ + return spectre_v2_state; +} + +#ifdef CONFIG_KVM +#include <asm/cacheflush.h> +#include <asm/kvm_asm.h> + +atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1); + +static void __copy_hyp_vect_bpi(int slot, const char *hyp_vecs_start, + const char *hyp_vecs_end) +{ + void *dst = lm_alias(__bp_harden_hyp_vecs + slot * SZ_2K); + int i; + + for (i = 0; i < SZ_2K; i += 0x80) + memcpy(dst + i, hyp_vecs_start, hyp_vecs_end - hyp_vecs_start); + + __flush_icache_range((uintptr_t)dst, (uintptr_t)dst + SZ_2K); +} + +static void install_bp_hardening_cb(bp_hardening_cb_t fn) +{ + static DEFINE_RAW_SPINLOCK(bp_lock); + int cpu, slot = -1; + const char *hyp_vecs_start = __smccc_workaround_1_smc; + const char *hyp_vecs_end = __smccc_workaround_1_smc + + __SMCCC_WORKAROUND_1_SMC_SZ; + + /* + * detect_harden_bp_fw() passes NULL for the hyp_vecs start/end if + * we're a guest. Skip the hyp-vectors work. + */ + if (!is_hyp_mode_available()) { + __this_cpu_write(bp_hardening_data.fn, fn); + return; + } + + raw_spin_lock(&bp_lock); + for_each_possible_cpu(cpu) { + if (per_cpu(bp_hardening_data.fn, cpu) == fn) { + slot = per_cpu(bp_hardening_data.hyp_vectors_slot, cpu); + break; + } + } + + if (slot == -1) { + slot = atomic_inc_return(&arm64_el2_vector_last_slot); + BUG_ON(slot >= BP_HARDEN_EL2_SLOTS); + __copy_hyp_vect_bpi(slot, hyp_vecs_start, hyp_vecs_end); + } + + __this_cpu_write(bp_hardening_data.hyp_vectors_slot, slot); + __this_cpu_write(bp_hardening_data.fn, fn); + raw_spin_unlock(&bp_lock); +} +#else +static void install_bp_hardening_cb(bp_hardening_cb_t fn) +{ + __this_cpu_write(bp_hardening_data.fn, fn); +} +#endif /* CONFIG_KVM */ + +static void call_smc_arch_workaround_1(void) +{ + arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); +} + +static void call_hvc_arch_workaround_1(void) +{ + arm_smccc_1_1_hvc(ARM_SMCCC_ARCH_WORKAROUND_1, NULL); +} + +static void qcom_link_stack_sanitisation(void) +{ + u64 tmp; + + asm volatile("mov %0, x30 \n" + ".rept 16 \n" + "bl . + 4 \n" + ".endr \n" + "mov x30, %0 \n" + : "=&r" (tmp)); +} + +static enum mitigation_state spectre_v2_enable_fw_mitigation(void) +{ + bp_hardening_cb_t cb; + enum mitigation_state state; + + state = spectre_v2_get_cpu_fw_mitigation_state(); + if (state != SPECTRE_MITIGATED) + return state; + + if (spectre_v2_mitigations_off()) + return SPECTRE_VULNERABLE; + + switch (arm_smccc_1_1_get_conduit()) { + case SMCCC_CONDUIT_HVC: + cb = call_hvc_arch_workaround_1; + break; + + case SMCCC_CONDUIT_SMC: + cb = call_smc_arch_workaround_1; + break; + + default: + return SPECTRE_VULNERABLE; + } + + install_bp_hardening_cb(cb); + return SPECTRE_MITIGATED; +} + +static enum mitigation_state spectre_v2_enable_sw_mitigation(void) +{ + u32 midr; + + if (spectre_v2_mitigations_off()) + return SPECTRE_VULNERABLE; + + midr = read_cpuid_id(); + if (((midr & MIDR_CPU_MODEL_MASK) != MIDR_QCOM_FALKOR) && + ((midr & MIDR_CPU_MODEL_MASK) != MIDR_QCOM_FALKOR_V1)) + return SPECTRE_VULNERABLE; + + install_bp_hardening_cb(qcom_link_stack_sanitisation); + return SPECTRE_MITIGATED; +} + +void spectre_v2_enable_mitigation(const struct arm64_cpu_capabilities *__unused) +{ + enum mitigation_state state; + + WARN_ON(preemptible()); + + state = spectre_v2_get_cpu_hw_mitigation_state(); + if (state == SPECTRE_VULNERABLE) + state = spectre_v2_enable_fw_mitigation(); + if (state == SPECTRE_VULNERABLE) + state = spectre_v2_enable_sw_mitigation(); + + update_mitigation_state(&spectre_v2_state, state); +} + +/* + * Spectre v4. + * + * If you thought Spectre v2 was nasty, wait until you see this mess. A CPU is + * either: + * + * - Mitigated in hardware and listed in our "safe list". + * - Mitigated in hardware via PSTATE.SSBS. + * - Mitigated in software by firmware (sometimes referred to as SSBD). + * + * Wait, that doesn't sound so bad, does it? Keep reading... + * + * A major source of headaches is that the software mitigation is enabled both + * on a per-task basis, but can also be forced on for the kernel, necessitating + * both context-switch *and* entry/exit hooks. To make it even worse, some CPUs + * allow EL0 to toggle SSBS directly, which can end up with the prctl() state + * being stale when re-entering the kernel. The usual big.LITTLE caveats apply, + * so you can have systems that have both firmware and SSBS mitigations. This + * means we actually have to reject late onlining of CPUs with mitigations if + * all of the currently onlined CPUs are safelisted, as the mitigation tends to + * be opt-in for userspace. Yes, really, the cure is worse than the disease. + * + * The only good part is that if the firmware mitigation is present, then it is + * present for all CPUs, meaning we don't have to worry about late onlining of a + * vulnerable CPU if one of the boot CPUs is using the firmware mitigation. + * + * Give me a VAX-11/780 any day of the week... + */ +static enum mitigation_state spectre_v4_state; + +/* This is the per-cpu state tracking whether we need to talk to firmware */ +DEFINE_PER_CPU_READ_MOSTLY(u64, arm64_ssbd_callback_required); + +enum spectre_v4_policy { + SPECTRE_V4_POLICY_MITIGATION_DYNAMIC, + SPECTRE_V4_POLICY_MITIGATION_ENABLED, + SPECTRE_V4_POLICY_MITIGATION_DISABLED, +}; + +static enum spectre_v4_policy __read_mostly __spectre_v4_policy; + +static const struct spectre_v4_param { + const char *str; + enum spectre_v4_policy policy; +} spectre_v4_params[] = { + { "force-on", SPECTRE_V4_POLICY_MITIGATION_ENABLED, }, + { "force-off", SPECTRE_V4_POLICY_MITIGATION_DISABLED, }, + { "kernel", SPECTRE_V4_POLICY_MITIGATION_DYNAMIC, }, +}; +static int __init parse_spectre_v4_param(char *str) +{ + int i; + + if (!str || !str[0]) + return -EINVAL; + + for (i = 0; i < ARRAY_SIZE(spectre_v4_params); i++) { + const struct spectre_v4_param *param = &spectre_v4_params[i]; + + if (strncmp(str, param->str, strlen(param->str))) + continue; + + __spectre_v4_policy = param->policy; + return 0; + } + + return -EINVAL; +} +early_param("ssbd", parse_spectre_v4_param); + +/* + * Because this was all written in a rush by people working in different silos, + * we've ended up with multiple command line options to control the same thing. + * Wrap these up in some helpers, which prefer disabling the mitigation if faced + * with contradictory parameters. The mitigation is always either "off", + * "dynamic" or "on". + */ +static bool spectre_v4_mitigations_off(void) +{ + bool ret = cpu_mitigations_off() || + __spectre_v4_policy == SPECTRE_V4_POLICY_MITIGATION_DISABLED; + + if (ret) + pr_info_once("spectre-v4 mitigation disabled by command-line option\n"); + + return ret; +} + +/* Do we need to toggle the mitigation state on entry to/exit from the kernel? */ +static bool spectre_v4_mitigations_dynamic(void) +{ + return !spectre_v4_mitigations_off() && + __spectre_v4_policy == SPECTRE_V4_POLICY_MITIGATION_DYNAMIC; +} + +static bool spectre_v4_mitigations_on(void) +{ + return !spectre_v4_mitigations_off() && + __spectre_v4_policy == SPECTRE_V4_POLICY_MITIGATION_ENABLED; +} + +ssize_t cpu_show_spec_store_bypass(struct device *dev, + struct device_attribute *attr, char *buf) +{ + switch (spectre_v4_state) { + case SPECTRE_UNAFFECTED: + return sprintf(buf, "Not affected\n"); + case SPECTRE_MITIGATED: + return sprintf(buf, "Mitigation: Speculative Store Bypass disabled via prctl\n"); + case SPECTRE_VULNERABLE: + fallthrough; + default: + return sprintf(buf, "Vulnerable\n"); + } +} + +enum mitigation_state arm64_get_spectre_v4_state(void) +{ + return spectre_v4_state; +} + +static enum mitigation_state spectre_v4_get_cpu_hw_mitigation_state(void) +{ + static const struct midr_range spectre_v4_safe_list[] = { + MIDR_ALL_VERSIONS(MIDR_CORTEX_A35), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A53), + MIDR_ALL_VERSIONS(MIDR_CORTEX_A55), + MIDR_ALL_VERSIONS(MIDR_BRAHMA_B53), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_3XX_SILVER), + MIDR_ALL_VERSIONS(MIDR_QCOM_KRYO_4XX_SILVER), + { /* sentinel */ }, + }; + + if (is_midr_in_range_list(read_cpuid_id(), spectre_v4_safe_list)) + return SPECTRE_UNAFFECTED; + + /* CPU features are detected first */ + if (this_cpu_has_cap(ARM64_SSBS)) + return SPECTRE_MITIGATED; + + return SPECTRE_VULNERABLE; +} + +static enum mitigation_state spectre_v4_get_cpu_fw_mitigation_state(void) +{ + int ret; + struct arm_smccc_res res; + + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_FEATURES_FUNC_ID, + ARM_SMCCC_ARCH_WORKAROUND_2, &res); + + ret = res.a0; + switch (ret) { + case SMCCC_RET_SUCCESS: + return SPECTRE_MITIGATED; + case SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED: + fallthrough; + case SMCCC_RET_NOT_REQUIRED: + return SPECTRE_UNAFFECTED; + default: + fallthrough; + case SMCCC_RET_NOT_SUPPORTED: + return SPECTRE_VULNERABLE; + } +} + +bool has_spectre_v4(const struct arm64_cpu_capabilities *cap, int scope) +{ + enum mitigation_state state; + + WARN_ON(scope != SCOPE_LOCAL_CPU || preemptible()); + + state = spectre_v4_get_cpu_hw_mitigation_state(); + if (state == SPECTRE_VULNERABLE) + state = spectre_v4_get_cpu_fw_mitigation_state(); + + return state != SPECTRE_UNAFFECTED; +} + +static int ssbs_emulation_handler(struct pt_regs *regs, u32 instr) +{ + if (user_mode(regs)) + return 1; + + if (instr & BIT(PSTATE_Imm_shift)) + regs->pstate |= PSR_SSBS_BIT; + else + regs->pstate &= ~PSR_SSBS_BIT; + + arm64_skip_faulting_instruction(regs, 4); + return 0; +} + +static struct undef_hook ssbs_emulation_hook = { + .instr_mask = ~(1U << PSTATE_Imm_shift), + .instr_val = 0xd500401f | PSTATE_SSBS, + .fn = ssbs_emulation_handler, +}; + +static enum mitigation_state spectre_v4_enable_hw_mitigation(void) +{ + static bool undef_hook_registered = false; + static DEFINE_RAW_SPINLOCK(hook_lock); + enum mitigation_state state; + + /* + * If the system is mitigated but this CPU doesn't have SSBS, then + * we must be on the safelist and there's nothing more to do. + */ + state = spectre_v4_get_cpu_hw_mitigation_state(); + if (state != SPECTRE_MITIGATED || !this_cpu_has_cap(ARM64_SSBS)) + return state; + + raw_spin_lock(&hook_lock); + if (!undef_hook_registered) { + register_undef_hook(&ssbs_emulation_hook); + undef_hook_registered = true; + } + raw_spin_unlock(&hook_lock); + + if (spectre_v4_mitigations_off()) { + sysreg_clear_set(sctlr_el1, 0, SCTLR_ELx_DSSBS); + asm volatile(SET_PSTATE_SSBS(1)); + return SPECTRE_VULNERABLE; + } + + /* SCTLR_EL1.DSSBS was initialised to 0 during boot */ + asm volatile(SET_PSTATE_SSBS(0)); + return SPECTRE_MITIGATED; +} + +/* + * Patch a branch over the Spectre-v4 mitigation code with a NOP so that + * we fallthrough and check whether firmware needs to be called on this CPU. + */ +void __init spectre_v4_patch_fw_mitigation_enable(struct alt_instr *alt, + __le32 *origptr, + __le32 *updptr, int nr_inst) +{ + BUG_ON(nr_inst != 1); /* Branch -> NOP */ + + if (spectre_v4_mitigations_off()) + return; + + if (cpus_have_final_cap(ARM64_SSBS)) + return; + + if (spectre_v4_mitigations_dynamic()) + *updptr = cpu_to_le32(aarch64_insn_gen_nop()); +} + +/* + * Patch a NOP in the Spectre-v4 mitigation code with an SMC/HVC instruction + * to call into firmware to adjust the mitigation state. + */ +void __init spectre_v4_patch_fw_mitigation_conduit(struct alt_instr *alt, + __le32 *origptr, + __le32 *updptr, int nr_inst) +{ + u32 insn; + + BUG_ON(nr_inst != 1); /* NOP -> HVC/SMC */ + + switch (arm_smccc_1_1_get_conduit()) { + case SMCCC_CONDUIT_HVC: + insn = aarch64_insn_get_hvc_value(); + break; + case SMCCC_CONDUIT_SMC: + insn = aarch64_insn_get_smc_value(); + break; + default: + return; + } + + *updptr = cpu_to_le32(insn); +} + +static enum mitigation_state spectre_v4_enable_fw_mitigation(void) +{ + enum mitigation_state state; + + state = spectre_v4_get_cpu_fw_mitigation_state(); + if (state != SPECTRE_MITIGATED) + return state; + + if (spectre_v4_mitigations_off()) { + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_WORKAROUND_2, false, NULL); + return SPECTRE_VULNERABLE; + } + + arm_smccc_1_1_invoke(ARM_SMCCC_ARCH_WORKAROUND_2, true, NULL); + + if (spectre_v4_mitigations_dynamic()) + __this_cpu_write(arm64_ssbd_callback_required, 1); + + return SPECTRE_MITIGATED; +} + +void spectre_v4_enable_mitigation(const struct arm64_cpu_capabilities *__unused) +{ + enum mitigation_state state; + + WARN_ON(preemptible()); + + state = spectre_v4_enable_hw_mitigation(); + if (state == SPECTRE_VULNERABLE) + state = spectre_v4_enable_fw_mitigation(); + + update_mitigation_state(&spectre_v4_state, state); +} + +static void __update_pstate_ssbs(struct pt_regs *regs, bool state) +{ + u64 bit = compat_user_mode(regs) ? PSR_AA32_SSBS_BIT : PSR_SSBS_BIT; + + if (state) + regs->pstate |= bit; + else + regs->pstate &= ~bit; +} + +void spectre_v4_enable_task_mitigation(struct task_struct *tsk) +{ + struct pt_regs *regs = task_pt_regs(tsk); + bool ssbs = false, kthread = tsk->flags & PF_KTHREAD; + + if (spectre_v4_mitigations_off()) + ssbs = true; + else if (spectre_v4_mitigations_dynamic() && !kthread) + ssbs = !test_tsk_thread_flag(tsk, TIF_SSBD); + + __update_pstate_ssbs(regs, ssbs); +} + +/* + * The Spectre-v4 mitigation can be controlled via a prctl() from userspace. + * This is interesting because the "speculation disabled" behaviour can be + * configured so that it is preserved across exec(), which means that the + * prctl() may be necessary even when PSTATE.SSBS can be toggled directly + * from userspace. + */ +static void ssbd_prctl_enable_mitigation(struct task_struct *task) +{ + task_clear_spec_ssb_noexec(task); + task_set_spec_ssb_disable(task); + set_tsk_thread_flag(task, TIF_SSBD); +} + +static void ssbd_prctl_disable_mitigation(struct task_struct *task) +{ + task_clear_spec_ssb_noexec(task); + task_clear_spec_ssb_disable(task); + clear_tsk_thread_flag(task, TIF_SSBD); +} + +static int ssbd_prctl_set(struct task_struct *task, unsigned long ctrl) +{ + switch (ctrl) { + case PR_SPEC_ENABLE: + /* Enable speculation: disable mitigation */ + /* + * Force disabled speculation prevents it from being + * re-enabled. + */ + if (task_spec_ssb_force_disable(task)) + return -EPERM; + + /* + * If the mitigation is forced on, then speculation is forced + * off and we again prevent it from being re-enabled. + */ + if (spectre_v4_mitigations_on()) + return -EPERM; + + ssbd_prctl_disable_mitigation(task); + break; + case PR_SPEC_FORCE_DISABLE: + /* Force disable speculation: force enable mitigation */ + /* + * If the mitigation is forced off, then speculation is forced + * on and we prevent it from being disabled. + */ + if (spectre_v4_mitigations_off()) + return -EPERM; + + task_set_spec_ssb_force_disable(task); + fallthrough; + case PR_SPEC_DISABLE: + /* Disable speculation: enable mitigation */ + /* Same as PR_SPEC_FORCE_DISABLE */ + if (spectre_v4_mitigations_off()) + return -EPERM; + + ssbd_prctl_enable_mitigation(task); + break; + case PR_SPEC_DISABLE_NOEXEC: + /* Disable speculation until execve(): enable mitigation */ + /* + * If the mitigation state is forced one way or the other, then + * we must fail now before we try to toggle it on execve(). + */ + if (task_spec_ssb_force_disable(task) || + spectre_v4_mitigations_off() || + spectre_v4_mitigations_on()) { + return -EPERM; + } + + ssbd_prctl_enable_mitigation(task); + task_set_spec_ssb_noexec(task); + break; + default: + return -ERANGE; + } + + spectre_v4_enable_task_mitigation(task); + return 0; +} + +int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which, + unsigned long ctrl) +{ + switch (which) { + case PR_SPEC_STORE_BYPASS: + return ssbd_prctl_set(task, ctrl); + default: + return -ENODEV; + } +} + +static int ssbd_prctl_get(struct task_struct *task) +{ + switch (spectre_v4_state) { + case SPECTRE_UNAFFECTED: + return PR_SPEC_NOT_AFFECTED; + case SPECTRE_MITIGATED: + if (spectre_v4_mitigations_on()) + return PR_SPEC_NOT_AFFECTED; + + if (spectre_v4_mitigations_dynamic()) + break; + + /* Mitigations are disabled, so we're vulnerable. */ + fallthrough; + case SPECTRE_VULNERABLE: + fallthrough; + default: + return PR_SPEC_ENABLE; + } + + /* Check the mitigation state for this task */ + if (task_spec_ssb_force_disable(task)) + return PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE; + + if (task_spec_ssb_noexec(task)) + return PR_SPEC_PRCTL | PR_SPEC_DISABLE_NOEXEC; + + if (task_spec_ssb_disable(task)) + return PR_SPEC_PRCTL | PR_SPEC_DISABLE; + + return PR_SPEC_PRCTL | PR_SPEC_ENABLE; +} + +int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which) +{ + switch (which) { + case PR_SPEC_STORE_BYPASS: + return ssbd_prctl_get(task); + default: + return -ENODEV; + } +} diff --git a/arch/arm64/kernel/ssbd.c b/arch/arm64/kernel/ssbd.c deleted file mode 100644 index b26955f56750..000000000000 --- a/arch/arm64/kernel/ssbd.c +++ /dev/null @@ -1,129 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Copyright (C) 2018 ARM Ltd, All Rights Reserved. - */ - -#include <linux/compat.h> -#include <linux/errno.h> -#include <linux/prctl.h> -#include <linux/sched.h> -#include <linux/sched/task_stack.h> -#include <linux/thread_info.h> - -#include <asm/cpufeature.h> - -static void ssbd_ssbs_enable(struct task_struct *task) -{ - u64 val = is_compat_thread(task_thread_info(task)) ? - PSR_AA32_SSBS_BIT : PSR_SSBS_BIT; - - task_pt_regs(task)->pstate |= val; -} - -static void ssbd_ssbs_disable(struct task_struct *task) -{ - u64 val = is_compat_thread(task_thread_info(task)) ? - PSR_AA32_SSBS_BIT : PSR_SSBS_BIT; - - task_pt_regs(task)->pstate &= ~val; -} - -/* - * prctl interface for SSBD - */ -static int ssbd_prctl_set(struct task_struct *task, unsigned long ctrl) -{ - int state = arm64_get_ssbd_state(); - - /* Unsupported */ - if (state == ARM64_SSBD_UNKNOWN) - return -ENODEV; - - /* Treat the unaffected/mitigated state separately */ - if (state == ARM64_SSBD_MITIGATED) { - switch (ctrl) { - case PR_SPEC_ENABLE: - return -EPERM; - case PR_SPEC_DISABLE: - case PR_SPEC_FORCE_DISABLE: - return 0; - } - } - - /* - * Things are a bit backward here: the arm64 internal API - * *enables the mitigation* when the userspace API *disables - * speculation*. So much fun. - */ - switch (ctrl) { - case PR_SPEC_ENABLE: - /* If speculation is force disabled, enable is not allowed */ - if (state == ARM64_SSBD_FORCE_ENABLE || - task_spec_ssb_force_disable(task)) - return -EPERM; - task_clear_spec_ssb_disable(task); - clear_tsk_thread_flag(task, TIF_SSBD); - ssbd_ssbs_enable(task); - break; - case PR_SPEC_DISABLE: - if (state == ARM64_SSBD_FORCE_DISABLE) - return -EPERM; - task_set_spec_ssb_disable(task); - set_tsk_thread_flag(task, TIF_SSBD); - ssbd_ssbs_disable(task); - break; - case PR_SPEC_FORCE_DISABLE: - if (state == ARM64_SSBD_FORCE_DISABLE) - return -EPERM; - task_set_spec_ssb_disable(task); - task_set_spec_ssb_force_disable(task); - set_tsk_thread_flag(task, TIF_SSBD); - ssbd_ssbs_disable(task); - break; - default: - return -ERANGE; - } - - return 0; -} - -int arch_prctl_spec_ctrl_set(struct task_struct *task, unsigned long which, - unsigned long ctrl) -{ - switch (which) { - case PR_SPEC_STORE_BYPASS: - return ssbd_prctl_set(task, ctrl); - default: - return -ENODEV; - } -} - -static int ssbd_prctl_get(struct task_struct *task) -{ - switch (arm64_get_ssbd_state()) { - case ARM64_SSBD_UNKNOWN: - return -ENODEV; - case ARM64_SSBD_FORCE_ENABLE: - return PR_SPEC_DISABLE; - case ARM64_SSBD_KERNEL: - if (task_spec_ssb_force_disable(task)) - return PR_SPEC_PRCTL | PR_SPEC_FORCE_DISABLE; - if (task_spec_ssb_disable(task)) - return PR_SPEC_PRCTL | PR_SPEC_DISABLE; - return PR_SPEC_PRCTL | PR_SPEC_ENABLE; - case ARM64_SSBD_FORCE_DISABLE: - return PR_SPEC_ENABLE; - default: - return PR_SPEC_NOT_AFFECTED; - } -} - -int arch_prctl_spec_ctrl_get(struct task_struct *task, unsigned long which) -{ - switch (which) { - case PR_SPEC_STORE_BYPASS: - return ssbd_prctl_get(task); - default: - return -ENODEV; - } -} diff --git a/arch/arm64/kernel/suspend.c b/arch/arm64/kernel/suspend.c index c1dee9066ff9..584c14ce3c86 100644 --- a/arch/arm64/kernel/suspend.c +++ b/arch/arm64/kernel/suspend.c @@ -72,8 +72,7 @@ void notrace __cpu_suspend_exit(void) * have turned the mitigation on. If the user has forcefully * disabled it, make sure their wishes are obeyed. */ - if (arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) - arm64_set_ssbd_mitigation(false); + spectre_v4_enable_mitigation(NULL); } /* diff --git a/arch/arm64/kernel/vmlinux.lds.S b/arch/arm64/kernel/vmlinux.lds.S index 7cba7623fcec..d52e6b5dbfd3 100644 --- a/arch/arm64/kernel/vmlinux.lds.S +++ b/arch/arm64/kernel/vmlinux.lds.S @@ -9,6 +9,7 @@ #include <asm-generic/vmlinux.lds.h> #include <asm/cache.h> +#include <asm/hyp_image.h> #include <asm/kernel-pgtable.h> #include <asm/memory.h> #include <asm/page.h> @@ -21,12 +22,23 @@ ENTRY(_text) jiffies = jiffies_64; +#ifdef CONFIG_KVM #define HYPERVISOR_EXTABLE \ . = ALIGN(SZ_8); \ __start___kvm_ex_table = .; \ *(__kvm_ex_table) \ __stop___kvm_ex_table = .; +#define HYPERVISOR_PERCPU_SECTION \ + . = ALIGN(PAGE_SIZE); \ + HYP_SECTION_NAME(.data..percpu) : { \ + *(HYP_SECTION_NAME(.data..percpu)) \ + } +#else /* CONFIG_KVM */ +#define HYPERVISOR_EXTABLE +#define HYPERVISOR_PERCPU_SECTION +#endif + #define HYPERVISOR_TEXT \ /* \ * Align to 4 KB so that \ @@ -190,6 +202,7 @@ SECTIONS } PERCPU_SECTION(L1_CACHE_BYTES) + HYPERVISOR_PERCPU_SECTION .rela.dyn : ALIGN(8) { *(.rela .rela*) diff --git a/arch/arm64/kvm/Kconfig b/arch/arm64/kvm/Kconfig index 318c8f2df245..043756db8f6e 100644 --- a/arch/arm64/kvm/Kconfig +++ b/arch/arm64/kvm/Kconfig @@ -57,9 +57,6 @@ config KVM_ARM_PMU Adds support for a virtual Performance Monitoring Unit (PMU) in virtual machines. -config KVM_INDIRECT_VECTORS - def_bool HARDEN_BRANCH_PREDICTOR || RANDOMIZE_BASE - endif # KVM endif # VIRTUALIZATION diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 99977c1972cc..1504c81fbf5d 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -13,7 +13,7 @@ obj-$(CONFIG_KVM) += hyp/ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ $(KVM)/vfio.o $(KVM)/irqchip.o \ arm.o mmu.o mmio.o psci.o perf.o hypercalls.o pvtime.o \ - inject_fault.o regmap.o va_layout.o hyp.o handle_exit.o \ + inject_fault.o regmap.o va_layout.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ aarch32.o arch_timer.o \ diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c index b588c3b5c2f0..f56122eedffc 100644 --- a/arch/arm64/kvm/arm.c +++ b/arch/arm64/kvm/arm.c @@ -46,8 +46,10 @@ __asm__(".arch_extension virt"); #endif -DEFINE_PER_CPU(kvm_host_data_t, kvm_host_data); +DECLARE_KVM_HYP_PER_CPU(unsigned long, kvm_hyp_vector); + static DEFINE_PER_CPU(unsigned long, kvm_arm_hyp_stack_page); +unsigned long kvm_arm_hyp_percpu_base[NR_CPUS]; /* The VMID used in the VTTBR */ static atomic64_t kvm_vmid_gen = ATOMIC64_INIT(1); @@ -145,6 +147,8 @@ void kvm_arch_destroy_vm(struct kvm *kvm) { int i; + bitmap_free(kvm->arch.pmu_filter); + kvm_vgic_destroy(kvm); for (i = 0; i < KVM_MAX_VCPUS; ++i) { @@ -286,7 +290,7 @@ void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) if (vcpu->arch.has_run_once && unlikely(!irqchip_in_kernel(vcpu->kvm))) static_branch_dec(&userspace_irqchip_in_use); - kvm_mmu_free_memory_caches(vcpu); + kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); kvm_timer_vcpu_terminate(vcpu); kvm_pmu_vcpu_destroy(vcpu); @@ -1259,12 +1263,60 @@ long kvm_arch_vm_ioctl(struct file *filp, } } +static unsigned long nvhe_percpu_size(void) +{ + return (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_end) - + (unsigned long)CHOOSE_NVHE_SYM(__per_cpu_start); +} + +static unsigned long nvhe_percpu_order(void) +{ + unsigned long size = nvhe_percpu_size(); + + return size ? get_order(size) : 0; +} + +static int kvm_map_vectors(void) +{ + /* + * SV2 = ARM64_SPECTRE_V2 + * HEL2 = ARM64_HARDEN_EL2_VECTORS + * + * !SV2 + !HEL2 -> use direct vectors + * SV2 + !HEL2 -> use hardened vectors in place + * !SV2 + HEL2 -> allocate one vector slot and use exec mapping + * SV2 + HEL2 -> use hardened vectors and use exec mapping + */ + if (cpus_have_const_cap(ARM64_SPECTRE_V2)) { + __kvm_bp_vect_base = kvm_ksym_ref(__bp_harden_hyp_vecs); + __kvm_bp_vect_base = kern_hyp_va(__kvm_bp_vect_base); + } + + if (cpus_have_const_cap(ARM64_HARDEN_EL2_VECTORS)) { + phys_addr_t vect_pa = __pa_symbol(__bp_harden_hyp_vecs); + unsigned long size = __BP_HARDEN_HYP_VECS_SZ; + + /* + * Always allocate a spare vector slot, as we don't + * know yet which CPUs have a BP hardening slot that + * we can reuse. + */ + __kvm_harden_el2_vector_slot = atomic_inc_return(&arm64_el2_vector_last_slot); + BUG_ON(__kvm_harden_el2_vector_slot >= BP_HARDEN_EL2_SLOTS); + return create_hyp_exec_mappings(vect_pa, size, + &__kvm_bp_vect_base); + } + + return 0; +} + static void cpu_init_hyp_mode(void) { phys_addr_t pgd_ptr; unsigned long hyp_stack_ptr; unsigned long vector_ptr; unsigned long tpidr_el2; + struct arm_smccc_res res; /* Switch from the HYP stub to our own HYP init vector */ __hyp_set_vectors(kvm_get_idmap_vector()); @@ -1274,12 +1326,13 @@ static void cpu_init_hyp_mode(void) * kernel's mapping to the linear mapping, and store it in tpidr_el2 * so that we can use adr_l to access per-cpu variables in EL2. */ - tpidr_el2 = ((unsigned long)this_cpu_ptr(&kvm_host_data) - - (unsigned long)kvm_ksym_ref(&kvm_host_data)); + tpidr_el2 = (unsigned long)this_cpu_ptr_nvhe_sym(__per_cpu_start) - + (unsigned long)kvm_ksym_ref(CHOOSE_NVHE_SYM(__per_cpu_start)); pgd_ptr = kvm_mmu_get_httbr(); hyp_stack_ptr = __this_cpu_read(kvm_arm_hyp_stack_page) + PAGE_SIZE; - vector_ptr = (unsigned long)kvm_get_hyp_vector(); + hyp_stack_ptr = kern_hyp_va(hyp_stack_ptr); + vector_ptr = (unsigned long)kern_hyp_va(kvm_ksym_ref(__kvm_hyp_host_vector)); /* * Call initialization code, and switch to the full blown HYP code. @@ -1288,14 +1341,16 @@ static void cpu_init_hyp_mode(void) * cpus_have_const_cap() wrapper. */ BUG_ON(!system_capabilities_finalized()); - __kvm_call_hyp((void *)pgd_ptr, hyp_stack_ptr, vector_ptr, tpidr_el2); + arm_smccc_1_1_hvc(KVM_HOST_SMCCC_FUNC(__kvm_hyp_init), + pgd_ptr, tpidr_el2, hyp_stack_ptr, vector_ptr, &res); + WARN_ON(res.a0 != SMCCC_RET_SUCCESS); /* * Disabling SSBD on a non-VHE system requires us to enable SSBS * at EL2. */ if (this_cpu_has_cap(ARM64_SSBS) && - arm64_get_ssbd_state() == ARM64_SSBD_FORCE_DISABLE) { + arm64_get_spectre_v4_state() == SPECTRE_VULNERABLE) { kvm_call_hyp_nvhe(__kvm_enable_ssbs); } } @@ -1308,10 +1363,12 @@ static void cpu_hyp_reset(void) static void cpu_hyp_reinit(void) { - kvm_init_host_cpu_context(&this_cpu_ptr(&kvm_host_data)->host_ctxt); + kvm_init_host_cpu_context(&this_cpu_ptr_hyp_sym(kvm_host_data)->host_ctxt); cpu_hyp_reset(); + *this_cpu_ptr_hyp_sym(kvm_hyp_vector) = (unsigned long)kvm_get_hyp_vector(); + if (is_kernel_in_hyp_mode()) kvm_timer_init_vhe(); else @@ -1462,8 +1519,10 @@ static void teardown_hyp_mode(void) int cpu; free_hyp_pgds(); - for_each_possible_cpu(cpu) + for_each_possible_cpu(cpu) { free_page(per_cpu(kvm_arm_hyp_stack_page, cpu)); + free_pages(kvm_arm_hyp_percpu_base[cpu], nvhe_percpu_order()); + } } /** @@ -1497,6 +1556,24 @@ static int init_hyp_mode(void) } /* + * Allocate and initialize pages for Hypervisor-mode percpu regions. + */ + for_each_possible_cpu(cpu) { + struct page *page; + void *page_addr; + + page = alloc_pages(GFP_KERNEL, nvhe_percpu_order()); + if (!page) { + err = -ENOMEM; + goto out_err; + } + + page_addr = page_address(page); + memcpy(page_addr, CHOOSE_NVHE_SYM(__per_cpu_start), nvhe_percpu_size()); + kvm_arm_hyp_percpu_base[cpu] = (unsigned long)page_addr; + } + + /* * Map the Hyp-code called directly from the host */ err = create_hyp_mappings(kvm_ksym_ref(__hyp_text_start), @@ -1540,22 +1617,21 @@ static int init_hyp_mode(void) } } + /* + * Map Hyp percpu pages + */ for_each_possible_cpu(cpu) { - kvm_host_data_t *cpu_data; + char *percpu_begin = (char *)kvm_arm_hyp_percpu_base[cpu]; + char *percpu_end = percpu_begin + nvhe_percpu_size(); - cpu_data = per_cpu_ptr(&kvm_host_data, cpu); - err = create_hyp_mappings(cpu_data, cpu_data + 1, PAGE_HYP); + err = create_hyp_mappings(percpu_begin, percpu_end, PAGE_HYP); if (err) { - kvm_err("Cannot map host CPU state: %d\n", err); + kvm_err("Cannot map hyp percpu region\n"); goto out_err; } } - err = hyp_map_aux_data(); - if (err) - kvm_err("Cannot map host auxiliary data: %d\n", err); - return 0; out_err: diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S deleted file mode 100644 index 3c79a1124af2..000000000000 --- a/arch/arm64/kvm/hyp.S +++ /dev/null @@ -1,34 +0,0 @@ -/* SPDX-License-Identifier: GPL-2.0-only */ -/* - * Copyright (C) 2012,2013 - ARM Ltd - * Author: Marc Zyngier <marc.zyngier@arm.com> - */ - -#include <linux/linkage.h> - -#include <asm/alternative.h> -#include <asm/assembler.h> -#include <asm/cpufeature.h> - -/* - * u64 __kvm_call_hyp(void *hypfn, ...); - * - * This is not really a variadic function in the classic C-way and care must - * be taken when calling this to ensure parameters are passed in registers - * only, since the stack will change between the caller and the callee. - * - * Call the function with the first argument containing a pointer to the - * function you wish to call in Hyp mode, and subsequent arguments will be - * passed as x0, x1, and x2 (a maximum of 3 arguments in addition to the - * function pointer can be passed). The function being called must be mapped - * in Hyp mode (see init_hyp_mode in arch/arm/kvm/arm.c). Return values are - * passed in x0. - * - * A function pointer with a value less than 0xfff has a special meaning, - * and is used to implement hyp stubs in the same way as in - * arch/arm64/kernel/hyp_stub.S. - */ -SYM_FUNC_START(__kvm_call_hyp) - hvc #0 - ret -SYM_FUNC_END(__kvm_call_hyp) diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile index f54f0e89a71c..4a81eddabcd8 100644 --- a/arch/arm64/kvm/hyp/Makefile +++ b/arch/arm64/kvm/hyp/Makefile @@ -10,5 +10,4 @@ subdir-ccflags-y := -I$(incdir) \ -DDISABLE_BRANCH_PROFILING \ $(DISABLE_STACKLEAK_PLUGIN) -obj-$(CONFIG_KVM) += vhe/ nvhe/ -obj-$(CONFIG_KVM_INDIRECT_VECTORS) += smccc_wa.o +obj-$(CONFIG_KVM) += vhe/ nvhe/ pgtable.o smccc_wa.o diff --git a/arch/arm64/kvm/hyp/entry.S b/arch/arm64/kvm/hyp/entry.S index 76e7eaf4675e..b0afad7a99c6 100644 --- a/arch/arm64/kvm/hyp/entry.S +++ b/arch/arm64/kvm/hyp/entry.S @@ -7,7 +7,6 @@ #include <linux/linkage.h> #include <asm/alternative.h> -#include <asm/asm-offsets.h> #include <asm/assembler.h> #include <asm/fpsimdmacros.h> #include <asm/kvm.h> @@ -16,66 +15,28 @@ #include <asm/kvm_mmu.h> #include <asm/kvm_ptrauth.h> -#define CPU_XREG_OFFSET(x) (CPU_USER_PT_REGS + 8*x) -#define CPU_SP_EL0_OFFSET (CPU_XREG_OFFSET(30) + 8) - .text /* - * We treat x18 as callee-saved as the host may use it as a platform - * register (e.g. for shadow call stack). - */ -.macro save_callee_saved_regs ctxt - str x18, [\ctxt, #CPU_XREG_OFFSET(18)] - stp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] - stp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] - stp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] - stp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] - stp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] - stp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] -.endm - -.macro restore_callee_saved_regs ctxt - // We require \ctxt is not x18-x28 - ldr x18, [\ctxt, #CPU_XREG_OFFSET(18)] - ldp x19, x20, [\ctxt, #CPU_XREG_OFFSET(19)] - ldp x21, x22, [\ctxt, #CPU_XREG_OFFSET(21)] - ldp x23, x24, [\ctxt, #CPU_XREG_OFFSET(23)] - ldp x25, x26, [\ctxt, #CPU_XREG_OFFSET(25)] - ldp x27, x28, [\ctxt, #CPU_XREG_OFFSET(27)] - ldp x29, lr, [\ctxt, #CPU_XREG_OFFSET(29)] -.endm - -.macro save_sp_el0 ctxt, tmp - mrs \tmp, sp_el0 - str \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] -.endm - -.macro restore_sp_el0 ctxt, tmp - ldr \tmp, [\ctxt, #CPU_SP_EL0_OFFSET] - msr sp_el0, \tmp -.endm - -/* - * u64 __guest_enter(struct kvm_vcpu *vcpu, - * struct kvm_cpu_context *host_ctxt); + * u64 __guest_enter(struct kvm_vcpu *vcpu); */ SYM_FUNC_START(__guest_enter) // x0: vcpu - // x1: host context - // x2-x17: clobbered by macros + // x1-x17: clobbered by macros // x29: guest context - // Store the host regs + adr_this_cpu x1, kvm_hyp_ctxt, x2 + + // Store the hyp regs save_callee_saved_regs x1 - // Save the host's sp_el0 + // Save hyp's sp_el0 save_sp_el0 x1, x2 - // Now the host state is stored if we have a pending RAS SError it must - // affect the host. If any asynchronous exception is pending we defer - // the guest entry. The DSB isn't necessary before v8.2 as any SError - // would be fatal. + // Now the hyp state is stored if we have a pending RAS SError it must + // affect the host or hyp. If any asynchronous exception is pending we + // defer the guest entry. The DSB isn't necessary before v8.2 as any + // SError would be fatal. alternative_if ARM64_HAS_RAS_EXTN dsb nshst isb @@ -86,6 +47,8 @@ alternative_else_nop_endif ret 1: + set_loaded_vcpu x0, x1, x2 + add x29, x0, #VCPU_CONTEXT // Macro ptrauth_switch_to_guest format: @@ -116,6 +79,26 @@ alternative_else_nop_endif eret sb +SYM_INNER_LABEL(__guest_exit_panic, SYM_L_GLOBAL) + // x2-x29,lr: vcpu regs + // vcpu x0-x1 on the stack + + // If the hyp context is loaded, go straight to hyp_panic + get_loaded_vcpu x0, x1 + cbz x0, hyp_panic + + // The hyp context is saved so make sure it is restored to allow + // hyp_panic to run at hyp and, subsequently, panic to run in the host. + // This makes use of __guest_exit to avoid duplication but sets the + // return address to tail call into hyp_panic. As a side effect, the + // current state is saved to the guest context but it will only be + // accurate if the guest had been completely restored. + adr_this_cpu x0, kvm_hyp_ctxt, x1 + adr x1, hyp_panic + str x1, [x0, #CPU_XREG_OFFSET(30)] + + get_vcpu_ptr x1, x0 + SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL) // x0: return code // x1: vcpu @@ -148,21 +131,23 @@ SYM_INNER_LABEL(__guest_exit, SYM_L_GLOBAL) // Store the guest's sp_el0 save_sp_el0 x1, x2 - get_host_ctxt x2, x3 + adr_this_cpu x2, kvm_hyp_ctxt, x3 - // Macro ptrauth_switch_to_guest format: - // ptrauth_switch_to_host(guest cxt, host cxt, tmp1, tmp2, tmp3) + // Macro ptrauth_switch_to_hyp format: + // ptrauth_switch_to_hyp(guest cxt, host cxt, tmp1, tmp2, tmp3) // The below macro to save/restore keys is not implemented in C code // as it may cause Pointer Authentication key signing mismatch errors // when this feature is enabled for kernel code. - ptrauth_switch_to_host x1, x2, x3, x4, x5 + ptrauth_switch_to_hyp x1, x2, x3, x4, x5 - // Restore the hosts's sp_el0 + // Restore hyp's sp_el0 restore_sp_el0 x2, x3 - // Now restore the host regs + // Now restore the hyp regs restore_callee_saved_regs x2 + set_loaded_vcpu xzr, x1, x2 + alternative_if ARM64_HAS_RAS_EXTN // If we have the RAS extensions we can consume a pending error // without an unmask-SError and isb. The ESB-instruction consumed any diff --git a/arch/arm64/kvm/hyp/hyp-entry.S b/arch/arm64/kvm/hyp/hyp-entry.S index 46b4dab933d0..0a5b36eb54b3 100644 --- a/arch/arm64/kvm/hyp/hyp-entry.S +++ b/arch/arm64/kvm/hyp/hyp-entry.S @@ -12,7 +12,6 @@ #include <asm/cpufeature.h> #include <asm/kvm_arm.h> #include <asm/kvm_asm.h> -#include <asm/kvm_mmu.h> #include <asm/mmu.h> .macro save_caller_saved_regs_vect @@ -41,20 +40,6 @@ .text -.macro do_el2_call - /* - * Shuffle the parameters before calling the function - * pointed to in x0. Assumes parameters in x[1,2,3]. - */ - str lr, [sp, #-16]! - mov lr, x0 - mov x0, x1 - mov x1, x2 - mov x2, x3 - blr lr - ldr lr, [sp], #16 -.endm - el1_sync: // Guest trapped into EL2 mrs x0, esr_el2 @@ -63,44 +48,6 @@ el1_sync: // Guest trapped into EL2 ccmp x0, #ESR_ELx_EC_HVC32, #4, ne b.ne el1_trap -#ifdef __KVM_NVHE_HYPERVISOR__ - mrs x1, vttbr_el2 // If vttbr is valid, the guest - cbnz x1, el1_hvc_guest // called HVC - - /* Here, we're pretty sure the host called HVC. */ - ldp x0, x1, [sp], #16 - - /* Check for a stub HVC call */ - cmp x0, #HVC_STUB_HCALL_NR - b.hs 1f - - /* - * Compute the idmap address of __kvm_handle_stub_hvc and - * jump there. Since we use kimage_voffset, do not use the - * HYP VA for __kvm_handle_stub_hvc, but the kernel VA instead - * (by loading it from the constant pool). - * - * Preserve x0-x4, which may contain stub parameters. - */ - ldr x5, =__kvm_handle_stub_hvc - ldr_l x6, kimage_voffset - - /* x5 = __pa(x5) */ - sub x5, x5, x6 - br x5 - -1: - /* - * Perform the EL2 call - */ - kern_hyp_va x0 - do_el2_call - - eret - sb -#endif /* __KVM_NVHE_HYPERVISOR__ */ - -el1_hvc_guest: /* * Fastest possible path for ARM_SMCCC_ARCH_WORKAROUND_1. * The workaround has already been applied on the host, @@ -116,35 +63,6 @@ el1_hvc_guest: ARM_SMCCC_ARCH_WORKAROUND_2) cbnz w1, el1_trap -#ifdef CONFIG_ARM64_SSBD -alternative_cb arm64_enable_wa2_handling - b wa2_end -alternative_cb_end - get_vcpu_ptr x2, x0 - ldr x0, [x2, #VCPU_WORKAROUND_FLAGS] - - // Sanitize the argument and update the guest flags - ldr x1, [sp, #8] // Guest's x1 - clz w1, w1 // Murphy's device: - lsr w1, w1, #5 // w1 = !!w1 without using - eor w1, w1, #1 // the flags... - bfi x0, x1, #VCPU_WORKAROUND_2_FLAG_SHIFT, #1 - str x0, [x2, #VCPU_WORKAROUND_FLAGS] - - /* Check that we actually need to perform the call */ - hyp_ldr_this_cpu x0, arm64_ssbd_callback_required, x2 - cbz x0, wa2_end - - mov w0, #ARM_SMCCC_ARCH_WORKAROUND_2 - smc #0 - - /* Don't leak data from the SMC call */ - mov x3, xzr -wa2_end: - mov x2, xzr - mov x1, xzr -#endif - wa_epilogue: mov x0, xzr add sp, sp, #16 @@ -198,24 +116,7 @@ el2_error: eret sb -#ifdef __KVM_NVHE_HYPERVISOR__ -SYM_FUNC_START(__hyp_do_panic) - mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ - PSR_MODE_EL1h) - msr spsr_el2, lr - ldr lr, =panic - msr elr_el2, lr - eret - sb -SYM_FUNC_END(__hyp_do_panic) -#endif - -SYM_CODE_START(__hyp_panic) - get_host_ctxt x0, x1 - b hyp_panic -SYM_CODE_END(__hyp_panic) - -.macro invalid_vector label, target = __hyp_panic +.macro invalid_vector label, target = __guest_exit_panic .align 2 SYM_CODE_START(\label) b \target @@ -227,7 +128,6 @@ SYM_CODE_END(\label) invalid_vector el2t_irq_invalid invalid_vector el2t_fiq_invalid invalid_vector el2t_error_invalid - invalid_vector el2h_sync_invalid invalid_vector el2h_irq_invalid invalid_vector el2h_fiq_invalid invalid_vector el1_fiq_invalid @@ -257,10 +157,9 @@ check_preamble_length 661b, 662b .macro invalid_vect target .align 7 661: - b \target nop + stp x0, x1, [sp, #-16]! 662: - ldp x0, x1, [sp], #16 b \target check_preamble_length 661b, 662b @@ -288,7 +187,6 @@ SYM_CODE_START(__kvm_hyp_vector) valid_vect el1_error // Error 32-bit EL1 SYM_CODE_END(__kvm_hyp_vector) -#ifdef CONFIG_KVM_INDIRECT_VECTORS .macro hyp_ventry .align 7 1: esb @@ -338,4 +236,3 @@ SYM_CODE_START(__bp_harden_hyp_vecs) 1: .org __bp_harden_hyp_vecs + __BP_HARDEN_HYP_VECS_SZ .org 1b SYM_CODE_END(__bp_harden_hyp_vecs) -#endif diff --git a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h index 5e28ea6aa097..4ebe9f558f3a 100644 --- a/arch/arm64/kvm/hyp/include/hyp/debug-sr.h +++ b/arch/arm64/kvm/hyp/include/hyp/debug-sr.h @@ -135,7 +135,7 @@ static inline void __debug_switch_to_guest_common(struct kvm_vcpu *vcpu) if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY)) return; - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; guest_ctxt = &vcpu->arch.ctxt; host_dbg = &vcpu->arch.host_debug_state.regs; guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr); @@ -154,7 +154,7 @@ static inline void __debug_switch_to_host_common(struct kvm_vcpu *vcpu) if (!(vcpu->arch.flags & KVM_ARM64_DEBUG_DIRTY)) return; - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; guest_ctxt = &vcpu->arch.ctxt; host_dbg = &vcpu->arch.host_debug_state.regs; guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr); diff --git a/arch/arm64/kvm/hyp/include/hyp/switch.h b/arch/arm64/kvm/hyp/include/hyp/switch.h index 0261308bf944..313a8fa3c721 100644 --- a/arch/arm64/kvm/hyp/include/hyp/switch.h +++ b/arch/arm64/kvm/hyp/include/hyp/switch.h @@ -126,11 +126,6 @@ static inline void ___deactivate_traps(struct kvm_vcpu *vcpu) } } -static inline void __activate_vm(struct kvm_s2_mmu *mmu) -{ - __load_guest_stage2(mmu); -} - static inline bool __translate_far_to_hpfar(u64 far, u64 *hpfar) { u64 par, tmp; @@ -377,6 +372,8 @@ static inline bool esr_is_ptrauth_trap(u32 esr) ctxt_sys_reg(ctxt, key ## KEYHI_EL1) = __val; \ } while(0) +DECLARE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); + static inline bool __hyp_handle_ptrauth(struct kvm_vcpu *vcpu) { struct kvm_cpu_context *ctxt; @@ -386,7 +383,7 @@ static inline bool __hyp_handle_ptrauth(struct kvm_vcpu *vcpu) !esr_is_ptrauth_trap(kvm_vcpu_get_esr(vcpu))) return false; - ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + ctxt = this_cpu_ptr(&kvm_hyp_ctxt); __ptrauth_save_key(ctxt, APIA); __ptrauth_save_key(ctxt, APIB); __ptrauth_save_key(ctxt, APDA); @@ -479,49 +476,15 @@ exit: return false; } -static inline bool __needs_ssbd_off(struct kvm_vcpu *vcpu) -{ - if (!cpus_have_final_cap(ARM64_SSBD)) - return false; - - return !(vcpu->arch.workaround_flags & VCPU_WORKAROUND_2_FLAG); -} - -static inline void __set_guest_arch_workaround_state(struct kvm_vcpu *vcpu) -{ -#ifdef CONFIG_ARM64_SSBD - /* - * The host runs with the workaround always present. If the - * guest wants it disabled, so be it... - */ - if (__needs_ssbd_off(vcpu) && - __hyp_this_cpu_read(arm64_ssbd_callback_required)) - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 0, NULL); -#endif -} - -static inline void __set_host_arch_workaround_state(struct kvm_vcpu *vcpu) -{ -#ifdef CONFIG_ARM64_SSBD - /* - * If the guest has disabled the workaround, bring it back on. - */ - if (__needs_ssbd_off(vcpu) && - __hyp_this_cpu_read(arm64_ssbd_callback_required)) - arm_smccc_1_1_smc(ARM_SMCCC_ARCH_WORKAROUND_2, 1, NULL); -#endif -} - static inline void __kvm_unexpected_el2_exception(void) { + extern char __guest_exit_panic[]; unsigned long addr, fixup; - struct kvm_cpu_context *host_ctxt; struct exception_table_entry *entry, *end; unsigned long elr_el2 = read_sysreg(elr_el2); entry = hyp_symbol_addr(__start___kvm_ex_table); end = hyp_symbol_addr(__stop___kvm_ex_table); - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; while (entry < end) { addr = (unsigned long)&entry->insn + entry->insn; @@ -536,7 +499,8 @@ static inline void __kvm_unexpected_el2_exception(void) return; } - hyp_panic(host_ctxt); + /* Trigger a panic after restoring the hyp context. */ + write_sysreg(__guest_exit_panic, elr_el2); } #endif /* __ARM64_KVM_HYP_SWITCH_H__ */ diff --git a/arch/arm64/kvm/hyp/nvhe/.gitignore b/arch/arm64/kvm/hyp/nvhe/.gitignore new file mode 100644 index 000000000000..695d73d0249e --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/.gitignore @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +hyp.lds diff --git a/arch/arm64/kvm/hyp/nvhe/Makefile b/arch/arm64/kvm/hyp/nvhe/Makefile index aef76487edc2..ddde15fe85f2 100644 --- a/arch/arm64/kvm/hyp/nvhe/Makefile +++ b/arch/arm64/kvm/hyp/nvhe/Makefile @@ -6,44 +6,50 @@ asflags-y := -D__KVM_NVHE_HYPERVISOR__ ccflags-y := -D__KVM_NVHE_HYPERVISOR__ -obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o +obj-y := timer-sr.o sysreg-sr.o debug-sr.o switch.o tlb.o hyp-init.o host.o hyp-main.o obj-y += ../vgic-v3-sr.o ../aarch32.o ../vgic-v2-cpuif-proxy.o ../entry.o \ ../fpsimd.o ../hyp-entry.o -obj-y := $(patsubst %.o,%.hyp.o,$(obj-y)) -extra-y := $(patsubst %.hyp.o,%.hyp.tmp.o,$(obj-y)) +## +## Build rules for compiling nVHE hyp code +## Output of this folder is `kvm_nvhe.o`, a partially linked object +## file containing all nVHE hyp code and data. +## -$(obj)/%.hyp.tmp.o: $(src)/%.c FORCE +hyp-obj := $(patsubst %.o,%.nvhe.o,$(obj-y)) +obj-y := kvm_nvhe.o +extra-y := $(hyp-obj) kvm_nvhe.tmp.o hyp.lds + +# 1) Compile all source files to `.nvhe.o` object files. The file extension +# avoids file name clashes for files shared with VHE. +$(obj)/%.nvhe.o: $(src)/%.c FORCE $(call if_changed_rule,cc_o_c) -$(obj)/%.hyp.tmp.o: $(src)/%.S FORCE +$(obj)/%.nvhe.o: $(src)/%.S FORCE $(call if_changed_rule,as_o_S) -$(obj)/%.hyp.o: $(obj)/%.hyp.tmp.o FORCE - $(call if_changed,hypcopy) -# Disable reordering functions by GCC (enabled at -O2). -# This pass puts functions into '.text.*' sections to aid the linker -# in optimizing ELF layout. See HYPCOPY comment below for more info. -ccflags-y += $(call cc-option,-fno-reorder-functions) +# 2) Compile linker script. +$(obj)/hyp.lds: $(src)/hyp.lds.S FORCE + $(call if_changed_dep,cpp_lds_S) + +# 3) Partially link all '.nvhe.o' files and apply the linker script. +# Prefixes names of ELF sections with '.hyp', eg. '.hyp.text'. +# Note: The following rule assumes that the 'ld' rule puts LDFLAGS before +# the list of dependencies to form '-T $(obj)/hyp.lds'. This is to +# keep the dependency on the target while avoiding an error from +# GNU ld if the linker script is passed to it twice. +LDFLAGS_kvm_nvhe.tmp.o := -r -T +$(obj)/kvm_nvhe.tmp.o: $(obj)/hyp.lds $(addprefix $(obj)/,$(hyp-obj)) FORCE + $(call if_changed,ld) + +# 4) Produce the final 'kvm_nvhe.o', ready to be linked into 'vmlinux'. +# Prefixes names of ELF symbols with '__kvm_nvhe_'. +$(obj)/kvm_nvhe.o: $(obj)/kvm_nvhe.tmp.o FORCE + $(call if_changed,hypcopy) # The HYPCOPY command uses `objcopy` to prefix all ELF symbol names -# and relevant ELF section names to avoid clashes with VHE code/data. -# -# Hyp code is assumed to be in the '.text' section of the input object -# files (with the exception of specialized sections such as -# '.hyp.idmap.text'). This assumption may be broken by a compiler that -# divides code into sections like '.text.unlikely' so as to optimize -# ELF layout. HYPCOPY checks that no such sections exist in the input -# using `objdump`, otherwise they would be linked together with other -# kernel code and not memory-mapped correctly at runtime. +# to avoid clashes with VHE code/data. quiet_cmd_hypcopy = HYPCOPY $@ - cmd_hypcopy = \ - if $(OBJDUMP) -h $< | grep -F '.text.'; then \ - echo "$@: function reordering not supported in nVHE hyp code" >&2; \ - /bin/false; \ - fi; \ - $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ \ - --rename-section=.text=.hyp.text \ - $< $@ + cmd_hypcopy = $(OBJCOPY) --prefix-symbols=__kvm_nvhe_ $< $@ # Remove ftrace and Shadow Call Stack CFLAGS. # This is equivalent to the 'notrace' and '__noscs' annotations. diff --git a/arch/arm64/kvm/hyp/nvhe/host.S b/arch/arm64/kvm/hyp/nvhe/host.S new file mode 100644 index 000000000000..ff9a0f547b9f --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/host.S @@ -0,0 +1,187 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Copyright (C) 2020 - Google Inc + * Author: Andrew Scull <ascull@google.com> + */ + +#include <linux/linkage.h> + +#include <asm/assembler.h> +#include <asm/kvm_asm.h> +#include <asm/kvm_mmu.h> + + .text + +SYM_FUNC_START(__host_exit) + stp x0, x1, [sp, #-16]! + + get_host_ctxt x0, x1 + + ALTERNATIVE(nop, SET_PSTATE_PAN(1), ARM64_HAS_PAN, CONFIG_ARM64_PAN) + + /* Store the host regs x2 and x3 */ + stp x2, x3, [x0, #CPU_XREG_OFFSET(2)] + + /* Retrieve the host regs x0-x1 from the stack */ + ldp x2, x3, [sp], #16 // x0, x1 + + /* Store the host regs x0-x1 and x4-x17 */ + stp x2, x3, [x0, #CPU_XREG_OFFSET(0)] + stp x4, x5, [x0, #CPU_XREG_OFFSET(4)] + stp x6, x7, [x0, #CPU_XREG_OFFSET(6)] + stp x8, x9, [x0, #CPU_XREG_OFFSET(8)] + stp x10, x11, [x0, #CPU_XREG_OFFSET(10)] + stp x12, x13, [x0, #CPU_XREG_OFFSET(12)] + stp x14, x15, [x0, #CPU_XREG_OFFSET(14)] + stp x16, x17, [x0, #CPU_XREG_OFFSET(16)] + + /* Store the host regs x18-x29, lr */ + save_callee_saved_regs x0 + + /* Save the host context pointer in x29 across the function call */ + mov x29, x0 + bl handle_trap + + /* Restore host regs x0-x17 */ + ldp x0, x1, [x29, #CPU_XREG_OFFSET(0)] + ldp x2, x3, [x29, #CPU_XREG_OFFSET(2)] + ldp x4, x5, [x29, #CPU_XREG_OFFSET(4)] + ldp x6, x7, [x29, #CPU_XREG_OFFSET(6)] + + /* x0-7 are use for panic arguments */ +__host_enter_for_panic: + ldp x8, x9, [x29, #CPU_XREG_OFFSET(8)] + ldp x10, x11, [x29, #CPU_XREG_OFFSET(10)] + ldp x12, x13, [x29, #CPU_XREG_OFFSET(12)] + ldp x14, x15, [x29, #CPU_XREG_OFFSET(14)] + ldp x16, x17, [x29, #CPU_XREG_OFFSET(16)] + + /* Restore host regs x18-x29, lr */ + restore_callee_saved_regs x29 + + /* Do not touch any register after this! */ +__host_enter_without_restoring: + eret + sb +SYM_FUNC_END(__host_exit) + +/* + * void __noreturn __hyp_do_panic(bool restore_host, u64 spsr, u64 elr, u64 par); + */ +SYM_FUNC_START(__hyp_do_panic) + /* Load the format arguments into x1-7 */ + mov x6, x3 + get_vcpu_ptr x7, x3 + + mrs x3, esr_el2 + mrs x4, far_el2 + mrs x5, hpfar_el2 + + /* Prepare and exit to the host's panic funciton. */ + mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ + PSR_MODE_EL1h) + msr spsr_el2, lr + ldr lr, =panic + msr elr_el2, lr + + /* + * Set the panic format string and enter the host, conditionally + * restoring the host context. + */ + cmp x0, xzr + ldr x0, =__hyp_panic_string + b.eq __host_enter_without_restoring + b __host_enter_for_panic +SYM_FUNC_END(__hyp_do_panic) + +.macro host_el1_sync_vect + .align 7 +.L__vect_start\@: + stp x0, x1, [sp, #-16]! + mrs x0, esr_el2 + lsr x0, x0, #ESR_ELx_EC_SHIFT + cmp x0, #ESR_ELx_EC_HVC64 + ldp x0, x1, [sp], #16 + b.ne __host_exit + + /* Check for a stub HVC call */ + cmp x0, #HVC_STUB_HCALL_NR + b.hs __host_exit + + /* + * Compute the idmap address of __kvm_handle_stub_hvc and + * jump there. Since we use kimage_voffset, do not use the + * HYP VA for __kvm_handle_stub_hvc, but the kernel VA instead + * (by loading it from the constant pool). + * + * Preserve x0-x4, which may contain stub parameters. + */ + ldr x5, =__kvm_handle_stub_hvc + ldr_l x6, kimage_voffset + + /* x5 = __pa(x5) */ + sub x5, x5, x6 + br x5 +.L__vect_end\@: +.if ((.L__vect_end\@ - .L__vect_start\@) > 0x80) + .error "host_el1_sync_vect larger than vector entry" +.endif +.endm + +.macro invalid_host_el2_vect + .align 7 + /* If a guest is loaded, panic out of it. */ + stp x0, x1, [sp, #-16]! + get_loaded_vcpu x0, x1 + cbnz x0, __guest_exit_panic + add sp, sp, #16 + + /* + * The panic may not be clean if the exception is taken before the host + * context has been saved by __host_exit or after the hyp context has + * been partially clobbered by __host_enter. + */ + b hyp_panic +.endm + +.macro invalid_host_el1_vect + .align 7 + mov x0, xzr /* restore_host = false */ + mrs x1, spsr_el2 + mrs x2, elr_el2 + mrs x3, par_el1 + b __hyp_do_panic +.endm + +/* + * The host vector does not use an ESB instruction in order to avoid consuming + * SErrors that should only be consumed by the host. Guest entry is deferred by + * __guest_enter if there are any pending asynchronous exceptions so hyp will + * always return to the host without having consumerd host SErrors. + * + * CONFIG_KVM_INDIRECT_VECTORS is not applied to the host vectors because the + * host knows about the EL2 vectors already, and there is no point in hiding + * them. + */ + .align 11 +SYM_CODE_START(__kvm_hyp_host_vector) + invalid_host_el2_vect // Synchronous EL2t + invalid_host_el2_vect // IRQ EL2t + invalid_host_el2_vect // FIQ EL2t + invalid_host_el2_vect // Error EL2t + + invalid_host_el2_vect // Synchronous EL2h + invalid_host_el2_vect // IRQ EL2h + invalid_host_el2_vect // FIQ EL2h + invalid_host_el2_vect // Error EL2h + + host_el1_sync_vect // Synchronous 64-bit EL1 + invalid_host_el1_vect // IRQ 64-bit EL1 + invalid_host_el1_vect // FIQ 64-bit EL1 + invalid_host_el1_vect // Error 64-bit EL1 + + invalid_host_el1_vect // Synchronous 32-bit EL1 + invalid_host_el1_vect // IRQ 32-bit EL1 + invalid_host_el1_vect // FIQ 32-bit EL1 + invalid_host_el1_vect // Error 32-bit EL1 +SYM_CODE_END(__kvm_hyp_host_vector) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-init.S b/arch/arm64/kvm/hyp/nvhe/hyp-init.S index d9434e90c06d..47224dc62c51 100644 --- a/arch/arm64/kvm/hyp/nvhe/hyp-init.S +++ b/arch/arm64/kvm/hyp/nvhe/hyp-init.S @@ -4,11 +4,13 @@ * Author: Marc Zyngier <marc.zyngier@arm.com> */ +#include <linux/arm-smccc.h> #include <linux/linkage.h> #include <asm/alternative.h> #include <asm/assembler.h> #include <asm/kvm_arm.h> +#include <asm/kvm_asm.h> #include <asm/kvm_mmu.h> #include <asm/pgtable-hwdef.h> #include <asm/sysreg.h> @@ -44,27 +46,37 @@ __invalid: b . /* - * x0: HYP pgd - * x1: HYP stack - * x2: HYP vectors - * x3: per-CPU offset + * x0: SMCCC function ID + * x1: HYP pgd + * x2: per-CPU offset + * x3: HYP stack + * x4: HYP vectors */ __do_hyp_init: /* Check for a stub HVC call */ cmp x0, #HVC_STUB_HCALL_NR b.lo __kvm_handle_stub_hvc - phys_to_ttbr x4, x0 + /* Set tpidr_el2 for use by HYP to free a register */ + msr tpidr_el2, x2 + + mov x2, #KVM_HOST_SMCCC_FUNC(__kvm_hyp_init) + cmp x0, x2 + b.eq 1f + mov x0, #SMCCC_RET_NOT_SUPPORTED + eret + +1: phys_to_ttbr x0, x1 alternative_if ARM64_HAS_CNP - orr x4, x4, #TTBR_CNP_BIT + orr x0, x0, #TTBR_CNP_BIT alternative_else_nop_endif - msr ttbr0_el2, x4 + msr ttbr0_el2, x0 - mrs x4, tcr_el1 - mov_q x5, TCR_EL2_MASK - and x4, x4, x5 - mov x5, #TCR_EL2_RES1 - orr x4, x4, x5 + mrs x0, tcr_el1 + mov_q x1, TCR_EL2_MASK + and x0, x0, x1 + mov x1, #TCR_EL2_RES1 + orr x0, x0, x1 /* * The ID map may be configured to use an extended virtual address @@ -80,18 +92,18 @@ alternative_else_nop_endif * * So use the same T0SZ value we use for the ID map. */ - ldr_l x5, idmap_t0sz - bfi x4, x5, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH + ldr_l x1, idmap_t0sz + bfi x0, x1, TCR_T0SZ_OFFSET, TCR_TxSZ_WIDTH /* * Set the PS bits in TCR_EL2. */ - tcr_compute_pa_size x4, #TCR_EL2_PS_SHIFT, x5, x6 + tcr_compute_pa_size x0, #TCR_EL2_PS_SHIFT, x1, x2 - msr tcr_el2, x4 + msr tcr_el2, x0 - mrs x4, mair_el1 - msr mair_el2, x4 + mrs x0, mair_el1 + msr mair_el2, x0 isb /* Invalidate the stale TLBs from Bootloader */ @@ -103,25 +115,22 @@ alternative_else_nop_endif * as well as the EE bit on BE. Drop the A flag since the compiler * is allowed to generate unaligned accesses. */ - mov_q x4, (SCTLR_EL2_RES1 | (SCTLR_ELx_FLAGS & ~SCTLR_ELx_A)) -CPU_BE( orr x4, x4, #SCTLR_ELx_EE) + mov_q x0, (SCTLR_EL2_RES1 | (SCTLR_ELx_FLAGS & ~SCTLR_ELx_A)) +CPU_BE( orr x0, x0, #SCTLR_ELx_EE) alternative_if ARM64_HAS_ADDRESS_AUTH - mov_q x5, (SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | \ + mov_q x1, (SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | \ SCTLR_ELx_ENDA | SCTLR_ELx_ENDB) - orr x4, x4, x5 + orr x0, x0, x1 alternative_else_nop_endif - msr sctlr_el2, x4 + msr sctlr_el2, x0 isb /* Set the stack and new vectors */ - kern_hyp_va x1 - mov sp, x1 - msr vbar_el2, x2 - - /* Set tpidr_el2 for use by HYP */ - msr tpidr_el2, x3 + mov sp, x3 + msr vbar_el2, x4 /* Hello, World! */ + mov x0, #SMCCC_RET_SUCCESS eret SYM_CODE_END(__kvm_hyp_init) diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-main.c b/arch/arm64/kvm/hyp/nvhe/hyp-main.c new file mode 100644 index 000000000000..e2eafe2c93af --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/hyp-main.c @@ -0,0 +1,117 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2020 - Google Inc + * Author: Andrew Scull <ascull@google.com> + */ + +#include <hyp/switch.h> + +#include <asm/kvm_asm.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_host.h> +#include <asm/kvm_hyp.h> +#include <asm/kvm_mmu.h> + +#include <kvm/arm_hypercalls.h> + +static void handle_host_hcall(unsigned long func_id, + struct kvm_cpu_context *host_ctxt) +{ + unsigned long ret = 0; + + switch (func_id) { + case KVM_HOST_SMCCC_FUNC(__kvm_vcpu_run): { + unsigned long r1 = host_ctxt->regs.regs[1]; + struct kvm_vcpu *vcpu = (struct kvm_vcpu *)r1; + + ret = __kvm_vcpu_run(kern_hyp_va(vcpu)); + break; + } + case KVM_HOST_SMCCC_FUNC(__kvm_flush_vm_context): + __kvm_flush_vm_context(); + break; + case KVM_HOST_SMCCC_FUNC(__kvm_tlb_flush_vmid_ipa): { + unsigned long r1 = host_ctxt->regs.regs[1]; + struct kvm_s2_mmu *mmu = (struct kvm_s2_mmu *)r1; + phys_addr_t ipa = host_ctxt->regs.regs[2]; + int level = host_ctxt->regs.regs[3]; + + __kvm_tlb_flush_vmid_ipa(kern_hyp_va(mmu), ipa, level); + break; + } + case KVM_HOST_SMCCC_FUNC(__kvm_tlb_flush_vmid): { + unsigned long r1 = host_ctxt->regs.regs[1]; + struct kvm_s2_mmu *mmu = (struct kvm_s2_mmu *)r1; + + __kvm_tlb_flush_vmid(kern_hyp_va(mmu)); + break; + } + case KVM_HOST_SMCCC_FUNC(__kvm_tlb_flush_local_vmid): { + unsigned long r1 = host_ctxt->regs.regs[1]; + struct kvm_s2_mmu *mmu = (struct kvm_s2_mmu *)r1; + + __kvm_tlb_flush_local_vmid(kern_hyp_va(mmu)); + break; + } + case KVM_HOST_SMCCC_FUNC(__kvm_timer_set_cntvoff): { + u64 cntvoff = host_ctxt->regs.regs[1]; + + __kvm_timer_set_cntvoff(cntvoff); + break; + } + case KVM_HOST_SMCCC_FUNC(__kvm_enable_ssbs): + __kvm_enable_ssbs(); + break; + case KVM_HOST_SMCCC_FUNC(__vgic_v3_get_ich_vtr_el2): + ret = __vgic_v3_get_ich_vtr_el2(); + break; + case KVM_HOST_SMCCC_FUNC(__vgic_v3_read_vmcr): + ret = __vgic_v3_read_vmcr(); + break; + case KVM_HOST_SMCCC_FUNC(__vgic_v3_write_vmcr): { + u32 vmcr = host_ctxt->regs.regs[1]; + + __vgic_v3_write_vmcr(vmcr); + break; + } + case KVM_HOST_SMCCC_FUNC(__vgic_v3_init_lrs): + __vgic_v3_init_lrs(); + break; + case KVM_HOST_SMCCC_FUNC(__kvm_get_mdcr_el2): + ret = __kvm_get_mdcr_el2(); + break; + case KVM_HOST_SMCCC_FUNC(__vgic_v3_save_aprs): { + unsigned long r1 = host_ctxt->regs.regs[1]; + struct vgic_v3_cpu_if *cpu_if = (struct vgic_v3_cpu_if *)r1; + + __vgic_v3_save_aprs(kern_hyp_va(cpu_if)); + break; + } + case KVM_HOST_SMCCC_FUNC(__vgic_v3_restore_aprs): { + unsigned long r1 = host_ctxt->regs.regs[1]; + struct vgic_v3_cpu_if *cpu_if = (struct vgic_v3_cpu_if *)r1; + + __vgic_v3_restore_aprs(kern_hyp_va(cpu_if)); + break; + } + default: + /* Invalid host HVC. */ + host_ctxt->regs.regs[0] = SMCCC_RET_NOT_SUPPORTED; + return; + } + + host_ctxt->regs.regs[0] = SMCCC_RET_SUCCESS; + host_ctxt->regs.regs[1] = ret; +} + +void handle_trap(struct kvm_cpu_context *host_ctxt) +{ + u64 esr = read_sysreg_el2(SYS_ESR); + unsigned long func_id; + + if (ESR_ELx_EC(esr) != ESR_ELx_EC_HVC64) + hyp_panic(); + + func_id = host_ctxt->regs.regs[0]; + handle_host_hcall(func_id, host_ctxt); +} diff --git a/arch/arm64/kvm/hyp/nvhe/hyp.lds.S b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S new file mode 100644 index 000000000000..bb2d986ff696 --- /dev/null +++ b/arch/arm64/kvm/hyp/nvhe/hyp.lds.S @@ -0,0 +1,19 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2020 Google LLC. + * Written by David Brazdil <dbrazdil@google.com> + * + * Linker script used for partial linking of nVHE EL2 object files. + */ + +#include <asm/hyp_image.h> +#include <asm-generic/vmlinux.lds.h> +#include <asm/cache.h> +#include <asm/memory.h> + +SECTIONS { + HYP_SECTION(.text) + HYP_SECTION_NAME(.data..percpu) : { + PERCPU_INPUT(L1_CACHE_BYTES) + } +} diff --git a/arch/arm64/kvm/hyp/nvhe/switch.c b/arch/arm64/kvm/hyp/nvhe/switch.c index 0970442d2dbc..a457a0306e03 100644 --- a/arch/arm64/kvm/hyp/nvhe/switch.c +++ b/arch/arm64/kvm/hyp/nvhe/switch.c @@ -27,6 +27,11 @@ #include <asm/processor.h> #include <asm/thread_info.h> +/* Non-VHE specific context */ +DEFINE_PER_CPU(struct kvm_host_data, kvm_host_data); +DEFINE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); +DEFINE_PER_CPU(unsigned long, kvm_hyp_vector); + static void __activate_traps(struct kvm_vcpu *vcpu) { u64 val; @@ -42,6 +47,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu) } write_sysreg(val, cptr_el2); + write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el2); if (cpus_have_final_cap(ARM64_WORKAROUND_SPECULATIVE_AT)) { struct kvm_cpu_context *ctxt = &vcpu->arch.ctxt; @@ -60,6 +66,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu) static void __deactivate_traps(struct kvm_vcpu *vcpu) { + extern char __kvm_hyp_host_vector[]; u64 mdcr_el2; ___deactivate_traps(vcpu); @@ -91,9 +98,10 @@ static void __deactivate_traps(struct kvm_vcpu *vcpu) write_sysreg(mdcr_el2, mdcr_el2); write_sysreg(HCR_HOST_NVHE_FLAGS, hcr_el2); write_sysreg(CPTR_EL2_DEFAULT, cptr_el2); + write_sysreg(__kvm_hyp_host_vector, vbar_el2); } -static void __deactivate_vm(struct kvm_vcpu *vcpu) +static void __load_host_stage2(void) { write_sysreg(0, vttbr_el2); } @@ -173,9 +181,7 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) pmr_sync(); } - vcpu = kern_hyp_va(vcpu); - - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; host_ctxt->__hyp_running_vcpu = vcpu; guest_ctxt = &vcpu->arch.ctxt; @@ -194,7 +200,7 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) __sysreg32_restore_state(vcpu); __sysreg_restore_state_nvhe(guest_ctxt); - __activate_vm(kern_hyp_va(vcpu->arch.hw_mmu)); + __load_guest_stage2(kern_hyp_va(vcpu->arch.hw_mmu)); __activate_traps(vcpu); __hyp_vgic_restore_state(vcpu); @@ -202,24 +208,20 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) __debug_switch_to_guest(vcpu); - __set_guest_arch_workaround_state(vcpu); - do { /* Jump in the fire! */ - exit_code = __guest_enter(vcpu, host_ctxt); + exit_code = __guest_enter(vcpu); /* And we're baaack! */ } while (fixup_guest_exit(vcpu, &exit_code)); - __set_host_arch_workaround_state(vcpu); - __sysreg_save_state_nvhe(guest_ctxt); __sysreg32_save_state(vcpu); __timer_disable_traps(vcpu); __hyp_vgic_save_state(vcpu); __deactivate_traps(vcpu); - __deactivate_vm(vcpu); + __load_host_stage2(); __sysreg_restore_state_nvhe(host_ctxt); @@ -239,35 +241,31 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) if (system_uses_irq_prio_masking()) gic_write_pmr(GIC_PRIO_IRQOFF); + host_ctxt->__hyp_running_vcpu = NULL; + return exit_code; } -void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt) +void __noreturn hyp_panic(void) { u64 spsr = read_sysreg_el2(SYS_SPSR); u64 elr = read_sysreg_el2(SYS_ELR); u64 par = read_sysreg(par_el1); - struct kvm_vcpu *vcpu = host_ctxt->__hyp_running_vcpu; - unsigned long str_va; + bool restore_host = true; + struct kvm_cpu_context *host_ctxt; + struct kvm_vcpu *vcpu; + + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; + vcpu = host_ctxt->__hyp_running_vcpu; - if (read_sysreg(vttbr_el2)) { + if (vcpu) { __timer_disable_traps(vcpu); __deactivate_traps(vcpu); - __deactivate_vm(vcpu); + __load_host_stage2(); __sysreg_restore_state_nvhe(host_ctxt); } - /* - * Force the panic string to be loaded from the literal pool, - * making sure it is a kernel address and not a PC-relative - * reference. - */ - asm volatile("ldr %0, =%1" : "=r" (str_va) : "S" (__hyp_panic_string)); - - __hyp_do_panic(str_va, - spsr, elr, - read_sysreg(esr_el2), read_sysreg_el2(SYS_FAR), - read_sysreg(hpfar_el2), par, vcpu); + __hyp_do_panic(restore_host, spsr, elr, par); unreachable(); } diff --git a/arch/arm64/kvm/hyp/nvhe/tlb.c b/arch/arm64/kvm/hyp/nvhe/tlb.c index 69eae608d670..544bca3072b7 100644 --- a/arch/arm64/kvm/hyp/nvhe/tlb.c +++ b/arch/arm64/kvm/hyp/nvhe/tlb.c @@ -54,7 +54,6 @@ void __kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, dsb(ishst); /* Switch to requested VMID */ - mmu = kern_hyp_va(mmu); __tlb_switch_to_guest(mmu, &cxt); /* @@ -108,7 +107,6 @@ void __kvm_tlb_flush_vmid(struct kvm_s2_mmu *mmu) dsb(ishst); /* Switch to requested VMID */ - mmu = kern_hyp_va(mmu); __tlb_switch_to_guest(mmu, &cxt); __tlbi(vmalls12e1is); diff --git a/arch/arm64/kvm/hyp/pgtable.c b/arch/arm64/kvm/hyp/pgtable.c new file mode 100644 index 000000000000..0cdf6e461cbd --- /dev/null +++ b/arch/arm64/kvm/hyp/pgtable.c @@ -0,0 +1,892 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Stand-alone page-table allocator for hyp stage-1 and guest stage-2. + * No bombay mix was harmed in the writing of this file. + * + * Copyright (C) 2020 Google LLC + * Author: Will Deacon <will@kernel.org> + */ + +#include <linux/bitfield.h> +#include <asm/kvm_pgtable.h> + +#define KVM_PGTABLE_MAX_LEVELS 4U + +#define KVM_PTE_VALID BIT(0) + +#define KVM_PTE_TYPE BIT(1) +#define KVM_PTE_TYPE_BLOCK 0 +#define KVM_PTE_TYPE_PAGE 1 +#define KVM_PTE_TYPE_TABLE 1 + +#define KVM_PTE_ADDR_MASK GENMASK(47, PAGE_SHIFT) +#define KVM_PTE_ADDR_51_48 GENMASK(15, 12) + +#define KVM_PTE_LEAF_ATTR_LO GENMASK(11, 2) + +#define KVM_PTE_LEAF_ATTR_LO_S1_ATTRIDX GENMASK(4, 2) +#define KVM_PTE_LEAF_ATTR_LO_S1_AP GENMASK(7, 6) +#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RO 3 +#define KVM_PTE_LEAF_ATTR_LO_S1_AP_RW 1 +#define KVM_PTE_LEAF_ATTR_LO_S1_SH GENMASK(9, 8) +#define KVM_PTE_LEAF_ATTR_LO_S1_SH_IS 3 +#define KVM_PTE_LEAF_ATTR_LO_S1_AF BIT(10) + +#define KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR GENMASK(5, 2) +#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R BIT(6) +#define KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W BIT(7) +#define KVM_PTE_LEAF_ATTR_LO_S2_SH GENMASK(9, 8) +#define KVM_PTE_LEAF_ATTR_LO_S2_SH_IS 3 +#define KVM_PTE_LEAF_ATTR_LO_S2_AF BIT(10) + +#define KVM_PTE_LEAF_ATTR_HI GENMASK(63, 51) + +#define KVM_PTE_LEAF_ATTR_HI_S1_XN BIT(54) + +#define KVM_PTE_LEAF_ATTR_HI_S2_XN BIT(54) + +struct kvm_pgtable_walk_data { + struct kvm_pgtable *pgt; + struct kvm_pgtable_walker *walker; + + u64 addr; + u64 end; +}; + +static u64 kvm_granule_shift(u32 level) +{ + /* Assumes KVM_PGTABLE_MAX_LEVELS is 4 */ + return ARM64_HW_PGTABLE_LEVEL_SHIFT(level); +} + +static u64 kvm_granule_size(u32 level) +{ + return BIT(kvm_granule_shift(level)); +} + +static bool kvm_block_mapping_supported(u64 addr, u64 end, u64 phys, u32 level) +{ + u64 granule = kvm_granule_size(level); + + /* + * Reject invalid block mappings and don't bother with 4TB mappings for + * 52-bit PAs. + */ + if (level == 0 || (PAGE_SIZE != SZ_4K && level == 1)) + return false; + + if (granule > (end - addr)) + return false; + + return IS_ALIGNED(addr, granule) && IS_ALIGNED(phys, granule); +} + +static u32 kvm_pgtable_idx(struct kvm_pgtable_walk_data *data, u32 level) +{ + u64 shift = kvm_granule_shift(level); + u64 mask = BIT(PAGE_SHIFT - 3) - 1; + + return (data->addr >> shift) & mask; +} + +static u32 __kvm_pgd_page_idx(struct kvm_pgtable *pgt, u64 addr) +{ + u64 shift = kvm_granule_shift(pgt->start_level - 1); /* May underflow */ + u64 mask = BIT(pgt->ia_bits) - 1; + + return (addr & mask) >> shift; +} + +static u32 kvm_pgd_page_idx(struct kvm_pgtable_walk_data *data) +{ + return __kvm_pgd_page_idx(data->pgt, data->addr); +} + +static u32 kvm_pgd_pages(u32 ia_bits, u32 start_level) +{ + struct kvm_pgtable pgt = { + .ia_bits = ia_bits, + .start_level = start_level, + }; + + return __kvm_pgd_page_idx(&pgt, -1ULL) + 1; +} + +static bool kvm_pte_valid(kvm_pte_t pte) +{ + return pte & KVM_PTE_VALID; +} + +static bool kvm_pte_table(kvm_pte_t pte, u32 level) +{ + if (level == KVM_PGTABLE_MAX_LEVELS - 1) + return false; + + if (!kvm_pte_valid(pte)) + return false; + + return FIELD_GET(KVM_PTE_TYPE, pte) == KVM_PTE_TYPE_TABLE; +} + +static u64 kvm_pte_to_phys(kvm_pte_t pte) +{ + u64 pa = pte & KVM_PTE_ADDR_MASK; + + if (PAGE_SHIFT == 16) + pa |= FIELD_GET(KVM_PTE_ADDR_51_48, pte) << 48; + + return pa; +} + +static kvm_pte_t kvm_phys_to_pte(u64 pa) +{ + kvm_pte_t pte = pa & KVM_PTE_ADDR_MASK; + + if (PAGE_SHIFT == 16) + pte |= FIELD_PREP(KVM_PTE_ADDR_51_48, pa >> 48); + + return pte; +} + +static kvm_pte_t *kvm_pte_follow(kvm_pte_t pte) +{ + return __va(kvm_pte_to_phys(pte)); +} + +static void kvm_set_invalid_pte(kvm_pte_t *ptep) +{ + kvm_pte_t pte = *ptep; + WRITE_ONCE(*ptep, pte & ~KVM_PTE_VALID); +} + +static void kvm_set_table_pte(kvm_pte_t *ptep, kvm_pte_t *childp) +{ + kvm_pte_t old = *ptep, pte = kvm_phys_to_pte(__pa(childp)); + + pte |= FIELD_PREP(KVM_PTE_TYPE, KVM_PTE_TYPE_TABLE); + pte |= KVM_PTE_VALID; + + WARN_ON(kvm_pte_valid(old)); + smp_store_release(ptep, pte); +} + +static bool kvm_set_valid_leaf_pte(kvm_pte_t *ptep, u64 pa, kvm_pte_t attr, + u32 level) +{ + kvm_pte_t old = *ptep, pte = kvm_phys_to_pte(pa); + u64 type = (level == KVM_PGTABLE_MAX_LEVELS - 1) ? KVM_PTE_TYPE_PAGE : + KVM_PTE_TYPE_BLOCK; + + pte |= attr & (KVM_PTE_LEAF_ATTR_LO | KVM_PTE_LEAF_ATTR_HI); + pte |= FIELD_PREP(KVM_PTE_TYPE, type); + pte |= KVM_PTE_VALID; + + /* Tolerate KVM recreating the exact same mapping. */ + if (kvm_pte_valid(old)) + return old == pte; + + smp_store_release(ptep, pte); + return true; +} + +static int kvm_pgtable_visitor_cb(struct kvm_pgtable_walk_data *data, u64 addr, + u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag) +{ + struct kvm_pgtable_walker *walker = data->walker; + return walker->cb(addr, data->end, level, ptep, flag, walker->arg); +} + +static int __kvm_pgtable_walk(struct kvm_pgtable_walk_data *data, + kvm_pte_t *pgtable, u32 level); + +static inline int __kvm_pgtable_visit(struct kvm_pgtable_walk_data *data, + kvm_pte_t *ptep, u32 level) +{ + int ret = 0; + u64 addr = data->addr; + kvm_pte_t *childp, pte = *ptep; + bool table = kvm_pte_table(pte, level); + enum kvm_pgtable_walk_flags flags = data->walker->flags; + + if (table && (flags & KVM_PGTABLE_WALK_TABLE_PRE)) { + ret = kvm_pgtable_visitor_cb(data, addr, level, ptep, + KVM_PGTABLE_WALK_TABLE_PRE); + } + + if (!table && (flags & KVM_PGTABLE_WALK_LEAF)) { + ret = kvm_pgtable_visitor_cb(data, addr, level, ptep, + KVM_PGTABLE_WALK_LEAF); + pte = *ptep; + table = kvm_pte_table(pte, level); + } + + if (ret) + goto out; + + if (!table) { + data->addr += kvm_granule_size(level); + goto out; + } + + childp = kvm_pte_follow(pte); + ret = __kvm_pgtable_walk(data, childp, level + 1); + if (ret) + goto out; + + if (flags & KVM_PGTABLE_WALK_TABLE_POST) { + ret = kvm_pgtable_visitor_cb(data, addr, level, ptep, + KVM_PGTABLE_WALK_TABLE_POST); + } + +out: + return ret; +} + +static int __kvm_pgtable_walk(struct kvm_pgtable_walk_data *data, + kvm_pte_t *pgtable, u32 level) +{ + u32 idx; + int ret = 0; + + if (WARN_ON_ONCE(level >= KVM_PGTABLE_MAX_LEVELS)) + return -EINVAL; + + for (idx = kvm_pgtable_idx(data, level); idx < PTRS_PER_PTE; ++idx) { + kvm_pte_t *ptep = &pgtable[idx]; + + if (data->addr >= data->end) + break; + + ret = __kvm_pgtable_visit(data, ptep, level); + if (ret) + break; + } + + return ret; +} + +static int _kvm_pgtable_walk(struct kvm_pgtable_walk_data *data) +{ + u32 idx; + int ret = 0; + struct kvm_pgtable *pgt = data->pgt; + u64 limit = BIT(pgt->ia_bits); + + if (data->addr > limit || data->end > limit) + return -ERANGE; + + if (!pgt->pgd) + return -EINVAL; + + for (idx = kvm_pgd_page_idx(data); data->addr < data->end; ++idx) { + kvm_pte_t *ptep = &pgt->pgd[idx * PTRS_PER_PTE]; + + ret = __kvm_pgtable_walk(data, ptep, pgt->start_level); + if (ret) + break; + } + + return ret; +} + +int kvm_pgtable_walk(struct kvm_pgtable *pgt, u64 addr, u64 size, + struct kvm_pgtable_walker *walker) +{ + struct kvm_pgtable_walk_data walk_data = { + .pgt = pgt, + .addr = ALIGN_DOWN(addr, PAGE_SIZE), + .end = PAGE_ALIGN(walk_data.addr + size), + .walker = walker, + }; + + return _kvm_pgtable_walk(&walk_data); +} + +struct hyp_map_data { + u64 phys; + kvm_pte_t attr; +}; + +static int hyp_map_set_prot_attr(enum kvm_pgtable_prot prot, + struct hyp_map_data *data) +{ + bool device = prot & KVM_PGTABLE_PROT_DEVICE; + u32 mtype = device ? MT_DEVICE_nGnRE : MT_NORMAL; + kvm_pte_t attr = FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_ATTRIDX, mtype); + u32 sh = KVM_PTE_LEAF_ATTR_LO_S1_SH_IS; + u32 ap = (prot & KVM_PGTABLE_PROT_W) ? KVM_PTE_LEAF_ATTR_LO_S1_AP_RW : + KVM_PTE_LEAF_ATTR_LO_S1_AP_RO; + + if (!(prot & KVM_PGTABLE_PROT_R)) + return -EINVAL; + + if (prot & KVM_PGTABLE_PROT_X) { + if (prot & KVM_PGTABLE_PROT_W) + return -EINVAL; + + if (device) + return -EINVAL; + } else { + attr |= KVM_PTE_LEAF_ATTR_HI_S1_XN; + } + + attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_AP, ap); + attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S1_SH, sh); + attr |= KVM_PTE_LEAF_ATTR_LO_S1_AF; + data->attr = attr; + return 0; +} + +static bool hyp_map_walker_try_leaf(u64 addr, u64 end, u32 level, + kvm_pte_t *ptep, struct hyp_map_data *data) +{ + u64 granule = kvm_granule_size(level), phys = data->phys; + + if (!kvm_block_mapping_supported(addr, end, phys, level)) + return false; + + WARN_ON(!kvm_set_valid_leaf_pte(ptep, phys, data->attr, level)); + data->phys += granule; + return true; +} + +static int hyp_map_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, void * const arg) +{ + kvm_pte_t *childp; + + if (hyp_map_walker_try_leaf(addr, end, level, ptep, arg)) + return 0; + + if (WARN_ON(level == KVM_PGTABLE_MAX_LEVELS - 1)) + return -EINVAL; + + childp = (kvm_pte_t *)get_zeroed_page(GFP_KERNEL); + if (!childp) + return -ENOMEM; + + kvm_set_table_pte(ptep, childp); + return 0; +} + +int kvm_pgtable_hyp_map(struct kvm_pgtable *pgt, u64 addr, u64 size, u64 phys, + enum kvm_pgtable_prot prot) +{ + int ret; + struct hyp_map_data map_data = { + .phys = ALIGN_DOWN(phys, PAGE_SIZE), + }; + struct kvm_pgtable_walker walker = { + .cb = hyp_map_walker, + .flags = KVM_PGTABLE_WALK_LEAF, + .arg = &map_data, + }; + + ret = hyp_map_set_prot_attr(prot, &map_data); + if (ret) + return ret; + + ret = kvm_pgtable_walk(pgt, addr, size, &walker); + dsb(ishst); + isb(); + return ret; +} + +int kvm_pgtable_hyp_init(struct kvm_pgtable *pgt, u32 va_bits) +{ + u64 levels = ARM64_HW_PGTABLE_LEVELS(va_bits); + + pgt->pgd = (kvm_pte_t *)get_zeroed_page(GFP_KERNEL); + if (!pgt->pgd) + return -ENOMEM; + + pgt->ia_bits = va_bits; + pgt->start_level = KVM_PGTABLE_MAX_LEVELS - levels; + pgt->mmu = NULL; + return 0; +} + +static int hyp_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, void * const arg) +{ + free_page((unsigned long)kvm_pte_follow(*ptep)); + return 0; +} + +void kvm_pgtable_hyp_destroy(struct kvm_pgtable *pgt) +{ + struct kvm_pgtable_walker walker = { + .cb = hyp_free_walker, + .flags = KVM_PGTABLE_WALK_TABLE_POST, + }; + + WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker)); + free_page((unsigned long)pgt->pgd); + pgt->pgd = NULL; +} + +struct stage2_map_data { + u64 phys; + kvm_pte_t attr; + + kvm_pte_t *anchor; + + struct kvm_s2_mmu *mmu; + struct kvm_mmu_memory_cache *memcache; +}; + +static int stage2_map_set_prot_attr(enum kvm_pgtable_prot prot, + struct stage2_map_data *data) +{ + bool device = prot & KVM_PGTABLE_PROT_DEVICE; + kvm_pte_t attr = device ? PAGE_S2_MEMATTR(DEVICE_nGnRE) : + PAGE_S2_MEMATTR(NORMAL); + u32 sh = KVM_PTE_LEAF_ATTR_LO_S2_SH_IS; + + if (!(prot & KVM_PGTABLE_PROT_X)) + attr |= KVM_PTE_LEAF_ATTR_HI_S2_XN; + else if (device) + return -EINVAL; + + if (prot & KVM_PGTABLE_PROT_R) + attr |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R; + + if (prot & KVM_PGTABLE_PROT_W) + attr |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W; + + attr |= FIELD_PREP(KVM_PTE_LEAF_ATTR_LO_S2_SH, sh); + attr |= KVM_PTE_LEAF_ATTR_LO_S2_AF; + data->attr = attr; + return 0; +} + +static bool stage2_map_walker_try_leaf(u64 addr, u64 end, u32 level, + kvm_pte_t *ptep, + struct stage2_map_data *data) +{ + u64 granule = kvm_granule_size(level), phys = data->phys; + + if (!kvm_block_mapping_supported(addr, end, phys, level)) + return false; + + if (kvm_set_valid_leaf_pte(ptep, phys, data->attr, level)) + goto out; + + /* There's an existing valid leaf entry, so perform break-before-make */ + kvm_set_invalid_pte(ptep); + kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level); + kvm_set_valid_leaf_pte(ptep, phys, data->attr, level); +out: + data->phys += granule; + return true; +} + +static int stage2_map_walk_table_pre(u64 addr, u64 end, u32 level, + kvm_pte_t *ptep, + struct stage2_map_data *data) +{ + if (data->anchor) + return 0; + + if (!kvm_block_mapping_supported(addr, end, data->phys, level)) + return 0; + + kvm_set_invalid_pte(ptep); + kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, 0); + data->anchor = ptep; + return 0; +} + +static int stage2_map_walk_leaf(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + struct stage2_map_data *data) +{ + kvm_pte_t *childp, pte = *ptep; + struct page *page = virt_to_page(ptep); + + if (data->anchor) { + if (kvm_pte_valid(pte)) + put_page(page); + + return 0; + } + + if (stage2_map_walker_try_leaf(addr, end, level, ptep, data)) + goto out_get_page; + + if (WARN_ON(level == KVM_PGTABLE_MAX_LEVELS - 1)) + return -EINVAL; + + if (!data->memcache) + return -ENOMEM; + + childp = kvm_mmu_memory_cache_alloc(data->memcache); + if (!childp) + return -ENOMEM; + + /* + * If we've run into an existing block mapping then replace it with + * a table. Accesses beyond 'end' that fall within the new table + * will be mapped lazily. + */ + if (kvm_pte_valid(pte)) { + kvm_set_invalid_pte(ptep); + kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, data->mmu, addr, level); + put_page(page); + } + + kvm_set_table_pte(ptep, childp); + +out_get_page: + get_page(page); + return 0; +} + +static int stage2_map_walk_table_post(u64 addr, u64 end, u32 level, + kvm_pte_t *ptep, + struct stage2_map_data *data) +{ + int ret = 0; + + if (!data->anchor) + return 0; + + free_page((unsigned long)kvm_pte_follow(*ptep)); + put_page(virt_to_page(ptep)); + + if (data->anchor == ptep) { + data->anchor = NULL; + ret = stage2_map_walk_leaf(addr, end, level, ptep, data); + } + + return ret; +} + +/* + * This is a little fiddly, as we use all three of the walk flags. The idea + * is that the TABLE_PRE callback runs for table entries on the way down, + * looking for table entries which we could conceivably replace with a + * block entry for this mapping. If it finds one, then it sets the 'anchor' + * field in 'struct stage2_map_data' to point at the table entry, before + * clearing the entry to zero and descending into the now detached table. + * + * The behaviour of the LEAF callback then depends on whether or not the + * anchor has been set. If not, then we're not using a block mapping higher + * up the table and we perform the mapping at the existing leaves instead. + * If, on the other hand, the anchor _is_ set, then we drop references to + * all valid leaves so that the pages beneath the anchor can be freed. + * + * Finally, the TABLE_POST callback does nothing if the anchor has not + * been set, but otherwise frees the page-table pages while walking back up + * the page-table, installing the block entry when it revisits the anchor + * pointer and clearing the anchor to NULL. + */ +static int stage2_map_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, void * const arg) +{ + struct stage2_map_data *data = arg; + + switch (flag) { + case KVM_PGTABLE_WALK_TABLE_PRE: + return stage2_map_walk_table_pre(addr, end, level, ptep, data); + case KVM_PGTABLE_WALK_LEAF: + return stage2_map_walk_leaf(addr, end, level, ptep, data); + case KVM_PGTABLE_WALK_TABLE_POST: + return stage2_map_walk_table_post(addr, end, level, ptep, data); + } + + return -EINVAL; +} + +int kvm_pgtable_stage2_map(struct kvm_pgtable *pgt, u64 addr, u64 size, + u64 phys, enum kvm_pgtable_prot prot, + struct kvm_mmu_memory_cache *mc) +{ + int ret; + struct stage2_map_data map_data = { + .phys = ALIGN_DOWN(phys, PAGE_SIZE), + .mmu = pgt->mmu, + .memcache = mc, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_map_walker, + .flags = KVM_PGTABLE_WALK_TABLE_PRE | + KVM_PGTABLE_WALK_LEAF | + KVM_PGTABLE_WALK_TABLE_POST, + .arg = &map_data, + }; + + ret = stage2_map_set_prot_attr(prot, &map_data); + if (ret) + return ret; + + ret = kvm_pgtable_walk(pgt, addr, size, &walker); + dsb(ishst); + return ret; +} + +static void stage2_flush_dcache(void *addr, u64 size) +{ + if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) + return; + + __flush_dcache_area(addr, size); +} + +static bool stage2_pte_cacheable(kvm_pte_t pte) +{ + u64 memattr = FIELD_GET(KVM_PTE_LEAF_ATTR_LO_S2_MEMATTR, pte); + return memattr == PAGE_S2_MEMATTR(NORMAL); +} + +static int stage2_unmap_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, + void * const arg) +{ + struct kvm_s2_mmu *mmu = arg; + kvm_pte_t pte = *ptep, *childp = NULL; + bool need_flush = false; + + if (!kvm_pte_valid(pte)) + return 0; + + if (kvm_pte_table(pte, level)) { + childp = kvm_pte_follow(pte); + + if (page_count(virt_to_page(childp)) != 1) + return 0; + } else if (stage2_pte_cacheable(pte)) { + need_flush = true; + } + + /* + * This is similar to the map() path in that we unmap the entire + * block entry and rely on the remaining portions being faulted + * back lazily. + */ + kvm_set_invalid_pte(ptep); + kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, addr, level); + put_page(virt_to_page(ptep)); + + if (need_flush) { + stage2_flush_dcache(kvm_pte_follow(pte), + kvm_granule_size(level)); + } + + if (childp) + free_page((unsigned long)childp); + + return 0; +} + +int kvm_pgtable_stage2_unmap(struct kvm_pgtable *pgt, u64 addr, u64 size) +{ + struct kvm_pgtable_walker walker = { + .cb = stage2_unmap_walker, + .arg = pgt->mmu, + .flags = KVM_PGTABLE_WALK_LEAF | KVM_PGTABLE_WALK_TABLE_POST, + }; + + return kvm_pgtable_walk(pgt, addr, size, &walker); +} + +struct stage2_attr_data { + kvm_pte_t attr_set; + kvm_pte_t attr_clr; + kvm_pte_t pte; + u32 level; +}; + +static int stage2_attr_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, + void * const arg) +{ + kvm_pte_t pte = *ptep; + struct stage2_attr_data *data = arg; + + if (!kvm_pte_valid(pte)) + return 0; + + data->level = level; + data->pte = pte; + pte &= ~data->attr_clr; + pte |= data->attr_set; + + /* + * We may race with the CPU trying to set the access flag here, + * but worst-case the access flag update gets lost and will be + * set on the next access instead. + */ + if (data->pte != pte) + WRITE_ONCE(*ptep, pte); + + return 0; +} + +static int stage2_update_leaf_attrs(struct kvm_pgtable *pgt, u64 addr, + u64 size, kvm_pte_t attr_set, + kvm_pte_t attr_clr, kvm_pte_t *orig_pte, + u32 *level) +{ + int ret; + kvm_pte_t attr_mask = KVM_PTE_LEAF_ATTR_LO | KVM_PTE_LEAF_ATTR_HI; + struct stage2_attr_data data = { + .attr_set = attr_set & attr_mask, + .attr_clr = attr_clr & attr_mask, + }; + struct kvm_pgtable_walker walker = { + .cb = stage2_attr_walker, + .arg = &data, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + ret = kvm_pgtable_walk(pgt, addr, size, &walker); + if (ret) + return ret; + + if (orig_pte) + *orig_pte = data.pte; + + if (level) + *level = data.level; + return 0; +} + +int kvm_pgtable_stage2_wrprotect(struct kvm_pgtable *pgt, u64 addr, u64 size) +{ + return stage2_update_leaf_attrs(pgt, addr, size, 0, + KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W, + NULL, NULL); +} + +kvm_pte_t kvm_pgtable_stage2_mkyoung(struct kvm_pgtable *pgt, u64 addr) +{ + kvm_pte_t pte = 0; + stage2_update_leaf_attrs(pgt, addr, 1, KVM_PTE_LEAF_ATTR_LO_S2_AF, 0, + &pte, NULL); + dsb(ishst); + return pte; +} + +kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr) +{ + kvm_pte_t pte = 0; + stage2_update_leaf_attrs(pgt, addr, 1, 0, KVM_PTE_LEAF_ATTR_LO_S2_AF, + &pte, NULL); + /* + * "But where's the TLBI?!", you scream. + * "Over in the core code", I sigh. + * + * See the '->clear_flush_young()' callback on the KVM mmu notifier. + */ + return pte; +} + +bool kvm_pgtable_stage2_is_young(struct kvm_pgtable *pgt, u64 addr) +{ + kvm_pte_t pte = 0; + stage2_update_leaf_attrs(pgt, addr, 1, 0, 0, &pte, NULL); + return pte & KVM_PTE_LEAF_ATTR_LO_S2_AF; +} + +int kvm_pgtable_stage2_relax_perms(struct kvm_pgtable *pgt, u64 addr, + enum kvm_pgtable_prot prot) +{ + int ret; + u32 level; + kvm_pte_t set = 0, clr = 0; + + if (prot & KVM_PGTABLE_PROT_R) + set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_R; + + if (prot & KVM_PGTABLE_PROT_W) + set |= KVM_PTE_LEAF_ATTR_LO_S2_S2AP_W; + + if (prot & KVM_PGTABLE_PROT_X) + clr |= KVM_PTE_LEAF_ATTR_HI_S2_XN; + + ret = stage2_update_leaf_attrs(pgt, addr, 1, set, clr, NULL, &level); + if (!ret) + kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, pgt->mmu, addr, level); + return ret; +} + +static int stage2_flush_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, + void * const arg) +{ + kvm_pte_t pte = *ptep; + + if (!kvm_pte_valid(pte) || !stage2_pte_cacheable(pte)) + return 0; + + stage2_flush_dcache(kvm_pte_follow(pte), kvm_granule_size(level)); + return 0; +} + +int kvm_pgtable_stage2_flush(struct kvm_pgtable *pgt, u64 addr, u64 size) +{ + struct kvm_pgtable_walker walker = { + .cb = stage2_flush_walker, + .flags = KVM_PGTABLE_WALK_LEAF, + }; + + if (cpus_have_const_cap(ARM64_HAS_STAGE2_FWB)) + return 0; + + return kvm_pgtable_walk(pgt, addr, size, &walker); +} + +int kvm_pgtable_stage2_init(struct kvm_pgtable *pgt, struct kvm *kvm) +{ + size_t pgd_sz; + u64 vtcr = kvm->arch.vtcr; + u32 ia_bits = VTCR_EL2_IPA(vtcr); + u32 sl0 = FIELD_GET(VTCR_EL2_SL0_MASK, vtcr); + u32 start_level = VTCR_EL2_TGRAN_SL0_BASE - sl0; + + pgd_sz = kvm_pgd_pages(ia_bits, start_level) * PAGE_SIZE; + pgt->pgd = alloc_pages_exact(pgd_sz, GFP_KERNEL | __GFP_ZERO); + if (!pgt->pgd) + return -ENOMEM; + + pgt->ia_bits = ia_bits; + pgt->start_level = start_level; + pgt->mmu = &kvm->arch.mmu; + + /* Ensure zeroed PGD pages are visible to the hardware walker */ + dsb(ishst); + return 0; +} + +static int stage2_free_walker(u64 addr, u64 end, u32 level, kvm_pte_t *ptep, + enum kvm_pgtable_walk_flags flag, + void * const arg) +{ + kvm_pte_t pte = *ptep; + + if (!kvm_pte_valid(pte)) + return 0; + + put_page(virt_to_page(ptep)); + + if (kvm_pte_table(pte, level)) + free_page((unsigned long)kvm_pte_follow(pte)); + + return 0; +} + +void kvm_pgtable_stage2_destroy(struct kvm_pgtable *pgt) +{ + size_t pgd_sz; + struct kvm_pgtable_walker walker = { + .cb = stage2_free_walker, + .flags = KVM_PGTABLE_WALK_LEAF | + KVM_PGTABLE_WALK_TABLE_POST, + }; + + WARN_ON(kvm_pgtable_walk(pgt, 0, BIT(pgt->ia_bits), &walker)); + pgd_sz = kvm_pgd_pages(pgt->ia_bits, pgt->start_level) * PAGE_SIZE; + free_pages_exact(pgt->pgd, pgd_sz); + pgt->pgd = NULL; +} diff --git a/arch/arm64/kvm/hyp/vhe/switch.c b/arch/arm64/kvm/hyp/vhe/switch.c index c1da4f86ccac..fe69de16dadc 100644 --- a/arch/arm64/kvm/hyp/vhe/switch.c +++ b/arch/arm64/kvm/hyp/vhe/switch.c @@ -28,6 +28,11 @@ const char __hyp_panic_string[] = "HYP panic:\nPS:%08llx PC:%016llx ESR:%08llx\nFAR:%016llx HPFAR:%016llx PAR:%016llx\nVCPU:%p\n"; +/* VHE specific context */ +DEFINE_PER_CPU(struct kvm_host_data, kvm_host_data); +DEFINE_PER_CPU(struct kvm_cpu_context, kvm_hyp_ctxt); +DEFINE_PER_CPU(unsigned long, kvm_hyp_vector); + static void __activate_traps(struct kvm_vcpu *vcpu) { u64 val; @@ -59,7 +64,7 @@ static void __activate_traps(struct kvm_vcpu *vcpu) write_sysreg(val, cpacr_el1); - write_sysreg(kvm_get_hyp_vector(), vbar_el1); + write_sysreg(__this_cpu_read(kvm_hyp_vector), vbar_el1); } NOKPROBE_SYMBOL(__activate_traps); @@ -108,7 +113,7 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) struct kvm_cpu_context *guest_ctxt; u64 exit_code; - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; host_ctxt->__hyp_running_vcpu = vcpu; guest_ctxt = &vcpu->arch.ctxt; @@ -120,28 +125,24 @@ static int __kvm_vcpu_run_vhe(struct kvm_vcpu *vcpu) * HCR_EL2.TGE. * * We have already configured the guest's stage 1 translation in - * kvm_vcpu_load_sysregs_vhe above. We must now call __activate_vm - * before __activate_traps, because __activate_vm configures - * stage 2 translation, and __activate_traps clear HCR_EL2.TGE - * (among other things). + * kvm_vcpu_load_sysregs_vhe above. We must now call + * __load_guest_stage2 before __activate_traps, because + * __load_guest_stage2 configures stage 2 translation, and + * __activate_traps clear HCR_EL2.TGE (among other things). */ - __activate_vm(vcpu->arch.hw_mmu); + __load_guest_stage2(vcpu->arch.hw_mmu); __activate_traps(vcpu); sysreg_restore_guest_state_vhe(guest_ctxt); __debug_switch_to_guest(vcpu); - __set_guest_arch_workaround_state(vcpu); - do { /* Jump in the fire! */ - exit_code = __guest_enter(vcpu, host_ctxt); + exit_code = __guest_enter(vcpu); /* And we're baaack! */ } while (fixup_guest_exit(vcpu, &exit_code)); - __set_host_arch_workaround_state(vcpu); - sysreg_save_guest_state_vhe(guest_ctxt); __deactivate_traps(vcpu); @@ -192,10 +193,12 @@ int __kvm_vcpu_run(struct kvm_vcpu *vcpu) return ret; } -static void __hyp_call_panic(u64 spsr, u64 elr, u64 par, - struct kvm_cpu_context *host_ctxt) +static void __hyp_call_panic(u64 spsr, u64 elr, u64 par) { + struct kvm_cpu_context *host_ctxt; struct kvm_vcpu *vcpu; + + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; vcpu = host_ctxt->__hyp_running_vcpu; __deactivate_traps(vcpu); @@ -208,13 +211,13 @@ static void __hyp_call_panic(u64 spsr, u64 elr, u64 par, } NOKPROBE_SYMBOL(__hyp_call_panic); -void __noreturn hyp_panic(struct kvm_cpu_context *host_ctxt) +void __noreturn hyp_panic(void) { u64 spsr = read_sysreg_el2(SYS_SPSR); u64 elr = read_sysreg_el2(SYS_ELR); u64 par = read_sysreg(par_el1); - __hyp_call_panic(spsr, elr, par, host_ctxt); + __hyp_call_panic(spsr, elr, par); unreachable(); } diff --git a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c index 996471e4c138..2a0b8c88d74f 100644 --- a/arch/arm64/kvm/hyp/vhe/sysreg-sr.c +++ b/arch/arm64/kvm/hyp/vhe/sysreg-sr.c @@ -66,7 +66,7 @@ void kvm_vcpu_load_sysregs_vhe(struct kvm_vcpu *vcpu) struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt; struct kvm_cpu_context *host_ctxt; - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; __sysreg_save_user_state(host_ctxt); /* @@ -100,7 +100,7 @@ void kvm_vcpu_put_sysregs_vhe(struct kvm_vcpu *vcpu) struct kvm_cpu_context *guest_ctxt = &vcpu->arch.ctxt; struct kvm_cpu_context *host_ctxt; - host_ctxt = &__hyp_this_cpu_ptr(kvm_host_data)->host_ctxt; + host_ctxt = &this_cpu_ptr(&kvm_host_data)->host_ctxt; deactivate_traps_vhe_put(); __sysreg_save_el1_state(guest_ctxt); diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 550dfa3e53cd..9824025ccc5c 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -24,27 +24,36 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) feature = smccc_get_arg1(vcpu); switch (feature) { case ARM_SMCCC_ARCH_WORKAROUND_1: - switch (kvm_arm_harden_branch_predictor()) { - case KVM_BP_HARDEN_UNKNOWN: + switch (arm64_get_spectre_v2_state()) { + case SPECTRE_VULNERABLE: break; - case KVM_BP_HARDEN_WA_NEEDED: + case SPECTRE_MITIGATED: val = SMCCC_RET_SUCCESS; break; - case KVM_BP_HARDEN_NOT_REQUIRED: + case SPECTRE_UNAFFECTED: val = SMCCC_RET_NOT_REQUIRED; break; } break; case ARM_SMCCC_ARCH_WORKAROUND_2: - switch (kvm_arm_have_ssbd()) { - case KVM_SSBD_FORCE_DISABLE: - case KVM_SSBD_UNKNOWN: + switch (arm64_get_spectre_v4_state()) { + case SPECTRE_VULNERABLE: break; - case KVM_SSBD_KERNEL: - val = SMCCC_RET_SUCCESS; - break; - case KVM_SSBD_FORCE_ENABLE: - case KVM_SSBD_MITIGATED: + case SPECTRE_MITIGATED: + /* + * SSBS everywhere: Indicate no firmware + * support, as the SSBS support will be + * indicated to the guest and the default is + * safe. + * + * Otherwise, expose a permanent mitigation + * to the guest, and hide SSBS so that the + * guest stays protected. + */ + if (cpus_have_final_cap(ARM64_SSBS)) + break; + fallthrough; + case SPECTRE_UNAFFECTED: val = SMCCC_RET_NOT_REQUIRED; break; } diff --git a/arch/arm64/kvm/inject_fault.c b/arch/arm64/kvm/inject_fault.c index ebfdfc27b2bd..34a96ab244fa 100644 --- a/arch/arm64/kvm/inject_fault.c +++ b/arch/arm64/kvm/inject_fault.c @@ -202,6 +202,7 @@ void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr) /** * kvm_inject_undefined - inject an undefined instruction into the guest + * @vcpu: The vCPU in which to inject the exception * * It is assumed that this code is called from the VCPU thread and that the * VCPU therefore is not currently executing guest code. diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 3d26b47a1343..19aacc7d64de 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -14,6 +14,7 @@ #include <asm/cacheflush.h> #include <asm/kvm_arm.h> #include <asm/kvm_mmu.h> +#include <asm/kvm_pgtable.h> #include <asm/kvm_ras.h> #include <asm/kvm_asm.h> #include <asm/kvm_emulate.h> @@ -21,9 +22,7 @@ #include "trace.h" -static pgd_t *boot_hyp_pgd; -static pgd_t *hyp_pgd; -static pgd_t *merged_hyp_pgd; +static struct kvm_pgtable *hyp_pgtable; static DEFINE_MUTEX(kvm_hyp_pgd_mutex); static unsigned long hyp_idmap_start; @@ -32,16 +31,42 @@ static phys_addr_t hyp_idmap_vector; static unsigned long io_map_base; -#define hyp_pgd_order get_order(PTRS_PER_PGD * sizeof(pgd_t)) -#define KVM_S2PTE_FLAG_IS_IOMAP (1UL << 0) -#define KVM_S2_FLAG_LOGGING_ACTIVE (1UL << 1) - -static bool is_iomap(unsigned long flags) +/* + * Release kvm_mmu_lock periodically if the memory region is large. Otherwise, + * we may see kernel panics with CONFIG_DETECT_HUNG_TASK, + * CONFIG_LOCKUP_DETECTOR, CONFIG_LOCKDEP. Additionally, holding the lock too + * long will also starve other vCPUs. We have to also make sure that the page + * tables are not freed while we released the lock. + */ +static int stage2_apply_range(struct kvm *kvm, phys_addr_t addr, + phys_addr_t end, + int (*fn)(struct kvm_pgtable *, u64, u64), + bool resched) { - return flags & KVM_S2PTE_FLAG_IS_IOMAP; + int ret; + u64 next; + + do { + struct kvm_pgtable *pgt = kvm->arch.mmu.pgt; + if (!pgt) + return -EINVAL; + + next = stage2_pgd_addr_end(kvm, addr, end); + ret = fn(pgt, addr, next - addr); + if (ret) + break; + + if (resched && next != end) + cond_resched_lock(&kvm->mmu_lock); + } while (addr = next, addr != end); + + return ret; } +#define stage2_apply_range_resched(kvm, addr, end, fn) \ + stage2_apply_range(kvm, addr, end, fn, true) + static bool memslot_is_logging(struct kvm_memory_slot *memslot) { return memslot->dirty_bitmap && !(memslot->flags & KVM_MEM_READONLY); @@ -58,154 +83,11 @@ void kvm_flush_remote_tlbs(struct kvm *kvm) kvm_call_hyp(__kvm_tlb_flush_vmid, &kvm->arch.mmu); } -static void kvm_tlb_flush_vmid_ipa(struct kvm_s2_mmu *mmu, phys_addr_t ipa, - int level) -{ - kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, mmu, ipa, level); -} - -/* - * D-Cache management functions. They take the page table entries by - * value, as they are flushing the cache using the kernel mapping (or - * kmap on 32bit). - */ -static void kvm_flush_dcache_pte(pte_t pte) -{ - __kvm_flush_dcache_pte(pte); -} - -static void kvm_flush_dcache_pmd(pmd_t pmd) -{ - __kvm_flush_dcache_pmd(pmd); -} - -static void kvm_flush_dcache_pud(pud_t pud) -{ - __kvm_flush_dcache_pud(pud); -} - static bool kvm_is_device_pfn(unsigned long pfn) { return !pfn_valid(pfn); } -/** - * stage2_dissolve_pmd() - clear and flush huge PMD entry - * @mmu: pointer to mmu structure to operate on - * @addr: IPA - * @pmd: pmd pointer for IPA - * - * Function clears a PMD entry, flushes addr 1st and 2nd stage TLBs. - */ -static void stage2_dissolve_pmd(struct kvm_s2_mmu *mmu, phys_addr_t addr, pmd_t *pmd) -{ - if (!pmd_thp_or_huge(*pmd)) - return; - - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL); - put_page(virt_to_page(pmd)); -} - -/** - * stage2_dissolve_pud() - clear and flush huge PUD entry - * @mmu: pointer to mmu structure to operate on - * @addr: IPA - * @pud: pud pointer for IPA - * - * Function clears a PUD entry, flushes addr 1st and 2nd stage TLBs. - */ -static void stage2_dissolve_pud(struct kvm_s2_mmu *mmu, phys_addr_t addr, pud_t *pudp) -{ - struct kvm *kvm = mmu->kvm; - - if (!stage2_pud_huge(kvm, *pudp)) - return; - - stage2_pud_clear(kvm, pudp); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL); - put_page(virt_to_page(pudp)); -} - -static void clear_stage2_pgd_entry(struct kvm_s2_mmu *mmu, pgd_t *pgd, phys_addr_t addr) -{ - struct kvm *kvm = mmu->kvm; - p4d_t *p4d_table __maybe_unused = stage2_p4d_offset(kvm, pgd, 0UL); - stage2_pgd_clear(kvm, pgd); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT); - stage2_p4d_free(kvm, p4d_table); - put_page(virt_to_page(pgd)); -} - -static void clear_stage2_p4d_entry(struct kvm_s2_mmu *mmu, p4d_t *p4d, phys_addr_t addr) -{ - struct kvm *kvm = mmu->kvm; - pud_t *pud_table __maybe_unused = stage2_pud_offset(kvm, p4d, 0); - stage2_p4d_clear(kvm, p4d); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT); - stage2_pud_free(kvm, pud_table); - put_page(virt_to_page(p4d)); -} - -static void clear_stage2_pud_entry(struct kvm_s2_mmu *mmu, pud_t *pud, phys_addr_t addr) -{ - struct kvm *kvm = mmu->kvm; - pmd_t *pmd_table __maybe_unused = stage2_pmd_offset(kvm, pud, 0); - - VM_BUG_ON(stage2_pud_huge(kvm, *pud)); - stage2_pud_clear(kvm, pud); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT); - stage2_pmd_free(kvm, pmd_table); - put_page(virt_to_page(pud)); -} - -static void clear_stage2_pmd_entry(struct kvm_s2_mmu *mmu, pmd_t *pmd, phys_addr_t addr) -{ - pte_t *pte_table = pte_offset_kernel(pmd, 0); - VM_BUG_ON(pmd_thp_or_huge(*pmd)); - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_NO_LEVEL_HINT); - free_page((unsigned long)pte_table); - put_page(virt_to_page(pmd)); -} - -static inline void kvm_set_pte(pte_t *ptep, pte_t new_pte) -{ - WRITE_ONCE(*ptep, new_pte); - dsb(ishst); -} - -static inline void kvm_set_pmd(pmd_t *pmdp, pmd_t new_pmd) -{ - WRITE_ONCE(*pmdp, new_pmd); - dsb(ishst); -} - -static inline void kvm_pmd_populate(pmd_t *pmdp, pte_t *ptep) -{ - kvm_set_pmd(pmdp, kvm_mk_pmd(ptep)); -} - -static inline void kvm_pud_populate(pud_t *pudp, pmd_t *pmdp) -{ - WRITE_ONCE(*pudp, kvm_mk_pud(pmdp)); - dsb(ishst); -} - -static inline void kvm_p4d_populate(p4d_t *p4dp, pud_t *pudp) -{ - WRITE_ONCE(*p4dp, kvm_mk_p4d(pudp)); - dsb(ishst); -} - -static inline void kvm_pgd_populate(pgd_t *pgdp, p4d_t *p4dp) -{ -#ifndef __PAGETABLE_P4D_FOLDED - WRITE_ONCE(*pgdp, kvm_mk_pgd(p4dp)); - dsb(ishst); -#endif -} - /* * Unmapping vs dcache management: * @@ -223,120 +105,19 @@ static inline void kvm_pgd_populate(pgd_t *pgdp, p4d_t *p4dp) * end up writing old data to disk. * * This is why right after unmapping a page/section and invalidating - * the corresponding TLBs, we call kvm_flush_dcache_p*() to make sure - * the IO subsystem will never hit in the cache. + * the corresponding TLBs, we flush to make sure the IO subsystem will + * never hit in the cache. * * This is all avoided on systems that have ARM64_HAS_STAGE2_FWB, as * we then fully enforce cacheability of RAM, no matter what the guest * does. */ -static void unmap_stage2_ptes(struct kvm_s2_mmu *mmu, pmd_t *pmd, - phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t start_addr = addr; - pte_t *pte, *start_pte; - - start_pte = pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte)) { - pte_t old_pte = *pte; - - kvm_set_pte(pte, __pte(0)); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PTE_LEVEL); - - /* No need to invalidate the cache for device mappings */ - if (!kvm_is_device_pfn(pte_pfn(old_pte))) - kvm_flush_dcache_pte(old_pte); - - put_page(virt_to_page(pte)); - } - } while (pte++, addr += PAGE_SIZE, addr != end); - - if (stage2_pte_table_empty(mmu->kvm, start_pte)) - clear_stage2_pmd_entry(mmu, pmd, start_addr); -} - -static void unmap_stage2_pmds(struct kvm_s2_mmu *mmu, pud_t *pud, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - phys_addr_t next, start_addr = addr; - pmd_t *pmd, *start_pmd; - - start_pmd = pmd = stage2_pmd_offset(kvm, pud, addr); - do { - next = stage2_pmd_addr_end(kvm, addr, end); - if (!pmd_none(*pmd)) { - if (pmd_thp_or_huge(*pmd)) { - pmd_t old_pmd = *pmd; - - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL); - - kvm_flush_dcache_pmd(old_pmd); - - put_page(virt_to_page(pmd)); - } else { - unmap_stage2_ptes(mmu, pmd, addr, next); - } - } - } while (pmd++, addr = next, addr != end); - - if (stage2_pmd_table_empty(kvm, start_pmd)) - clear_stage2_pud_entry(mmu, pud, start_addr); -} - -static void unmap_stage2_puds(struct kvm_s2_mmu *mmu, p4d_t *p4d, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - phys_addr_t next, start_addr = addr; - pud_t *pud, *start_pud; - - start_pud = pud = stage2_pud_offset(kvm, p4d, addr); - do { - next = stage2_pud_addr_end(kvm, addr, end); - if (!stage2_pud_none(kvm, *pud)) { - if (stage2_pud_huge(kvm, *pud)) { - pud_t old_pud = *pud; - - stage2_pud_clear(kvm, pud); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL); - kvm_flush_dcache_pud(old_pud); - put_page(virt_to_page(pud)); - } else { - unmap_stage2_pmds(mmu, pud, addr, next); - } - } - } while (pud++, addr = next, addr != end); - - if (stage2_pud_table_empty(kvm, start_pud)) - clear_stage2_p4d_entry(mmu, p4d, start_addr); -} - -static void unmap_stage2_p4ds(struct kvm_s2_mmu *mmu, pgd_t *pgd, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - phys_addr_t next, start_addr = addr; - p4d_t *p4d, *start_p4d; - - start_p4d = p4d = stage2_p4d_offset(kvm, pgd, addr); - do { - next = stage2_p4d_addr_end(kvm, addr, end); - if (!stage2_p4d_none(kvm, *p4d)) - unmap_stage2_puds(mmu, p4d, addr, next); - } while (p4d++, addr = next, addr != end); - - if (stage2_p4d_table_empty(kvm, start_p4d)) - clear_stage2_pgd_entry(mmu, pgd, start_addr); -} - /** * unmap_stage2_range -- Clear stage2 page table entries to unmap a range - * @kvm: The VM pointer + * @mmu: The KVM stage-2 MMU pointer * @start: The intermediate physical base address of the range to unmap * @size: The size of the area to unmap + * @may_block: Whether or not we are permitted to block * * Clear a range of stage-2 mappings, lowering the various ref-counts. Must * be called while holding mmu_lock (unless for freeing the stage2 pgd before @@ -347,32 +128,12 @@ static void __unmap_stage2_range(struct kvm_s2_mmu *mmu, phys_addr_t start, u64 bool may_block) { struct kvm *kvm = mmu->kvm; - pgd_t *pgd; - phys_addr_t addr = start, end = start + size; - phys_addr_t next; + phys_addr_t end = start + size; assert_spin_locked(&kvm->mmu_lock); WARN_ON(size & ~PAGE_MASK); - - pgd = mmu->pgd + stage2_pgd_index(kvm, addr); - do { - /* - * Make sure the page table is still active, as another thread - * could have possibly freed the page table, while we released - * the lock. - */ - if (!READ_ONCE(mmu->pgd)) - break; - next = stage2_pgd_addr_end(kvm, addr, end); - if (!stage2_pgd_none(kvm, *pgd)) - unmap_stage2_p4ds(mmu, pgd, addr, next); - /* - * If the range is too large, release the kvm->mmu_lock - * to prevent starvation and lockup detector warnings. - */ - if (may_block && next != end) - cond_resched_lock(&kvm->mmu_lock); - } while (pgd++, addr = next, addr != end); + WARN_ON(stage2_apply_range(kvm, start, end, kvm_pgtable_stage2_unmap, + may_block)); } static void unmap_stage2_range(struct kvm_s2_mmu *mmu, phys_addr_t start, u64 size) @@ -380,89 +141,13 @@ static void unmap_stage2_range(struct kvm_s2_mmu *mmu, phys_addr_t start, u64 si __unmap_stage2_range(mmu, start, size, true); } -static void stage2_flush_ptes(struct kvm_s2_mmu *mmu, pmd_t *pmd, - phys_addr_t addr, phys_addr_t end) -{ - pte_t *pte; - - pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte) && !kvm_is_device_pfn(pte_pfn(*pte))) - kvm_flush_dcache_pte(*pte); - } while (pte++, addr += PAGE_SIZE, addr != end); -} - -static void stage2_flush_pmds(struct kvm_s2_mmu *mmu, pud_t *pud, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - pmd_t *pmd; - phys_addr_t next; - - pmd = stage2_pmd_offset(kvm, pud, addr); - do { - next = stage2_pmd_addr_end(kvm, addr, end); - if (!pmd_none(*pmd)) { - if (pmd_thp_or_huge(*pmd)) - kvm_flush_dcache_pmd(*pmd); - else - stage2_flush_ptes(mmu, pmd, addr, next); - } - } while (pmd++, addr = next, addr != end); -} - -static void stage2_flush_puds(struct kvm_s2_mmu *mmu, p4d_t *p4d, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - pud_t *pud; - phys_addr_t next; - - pud = stage2_pud_offset(kvm, p4d, addr); - do { - next = stage2_pud_addr_end(kvm, addr, end); - if (!stage2_pud_none(kvm, *pud)) { - if (stage2_pud_huge(kvm, *pud)) - kvm_flush_dcache_pud(*pud); - else - stage2_flush_pmds(mmu, pud, addr, next); - } - } while (pud++, addr = next, addr != end); -} - -static void stage2_flush_p4ds(struct kvm_s2_mmu *mmu, pgd_t *pgd, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - p4d_t *p4d; - phys_addr_t next; - - p4d = stage2_p4d_offset(kvm, pgd, addr); - do { - next = stage2_p4d_addr_end(kvm, addr, end); - if (!stage2_p4d_none(kvm, *p4d)) - stage2_flush_puds(mmu, p4d, addr, next); - } while (p4d++, addr = next, addr != end); -} - static void stage2_flush_memslot(struct kvm *kvm, struct kvm_memory_slot *memslot) { - struct kvm_s2_mmu *mmu = &kvm->arch.mmu; phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT; phys_addr_t end = addr + PAGE_SIZE * memslot->npages; - phys_addr_t next; - pgd_t *pgd; - pgd = mmu->pgd + stage2_pgd_index(kvm, addr); - do { - next = stage2_pgd_addr_end(kvm, addr, end); - if (!stage2_pgd_none(kvm, *pgd)) - stage2_flush_p4ds(mmu, pgd, addr, next); - - if (next != end) - cond_resched_lock(&kvm->mmu_lock); - } while (pgd++, addr = next, addr != end); + stage2_apply_range_resched(kvm, addr, end, kvm_pgtable_stage2_flush); } /** @@ -489,338 +174,28 @@ static void stage2_flush_vm(struct kvm *kvm) srcu_read_unlock(&kvm->srcu, idx); } -static void clear_hyp_pgd_entry(pgd_t *pgd) -{ - p4d_t *p4d_table __maybe_unused = p4d_offset(pgd, 0UL); - pgd_clear(pgd); - p4d_free(NULL, p4d_table); - put_page(virt_to_page(pgd)); -} - -static void clear_hyp_p4d_entry(p4d_t *p4d) -{ - pud_t *pud_table __maybe_unused = pud_offset(p4d, 0UL); - VM_BUG_ON(p4d_huge(*p4d)); - p4d_clear(p4d); - pud_free(NULL, pud_table); - put_page(virt_to_page(p4d)); -} - -static void clear_hyp_pud_entry(pud_t *pud) -{ - pmd_t *pmd_table __maybe_unused = pmd_offset(pud, 0); - VM_BUG_ON(pud_huge(*pud)); - pud_clear(pud); - pmd_free(NULL, pmd_table); - put_page(virt_to_page(pud)); -} - -static void clear_hyp_pmd_entry(pmd_t *pmd) -{ - pte_t *pte_table = pte_offset_kernel(pmd, 0); - VM_BUG_ON(pmd_thp_or_huge(*pmd)); - pmd_clear(pmd); - pte_free_kernel(NULL, pte_table); - put_page(virt_to_page(pmd)); -} - -static void unmap_hyp_ptes(pmd_t *pmd, phys_addr_t addr, phys_addr_t end) -{ - pte_t *pte, *start_pte; - - start_pte = pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte)) { - kvm_set_pte(pte, __pte(0)); - put_page(virt_to_page(pte)); - } - } while (pte++, addr += PAGE_SIZE, addr != end); - - if (hyp_pte_table_empty(start_pte)) - clear_hyp_pmd_entry(pmd); -} - -static void unmap_hyp_pmds(pud_t *pud, phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t next; - pmd_t *pmd, *start_pmd; - - start_pmd = pmd = pmd_offset(pud, addr); - do { - next = pmd_addr_end(addr, end); - /* Hyp doesn't use huge pmds */ - if (!pmd_none(*pmd)) - unmap_hyp_ptes(pmd, addr, next); - } while (pmd++, addr = next, addr != end); - - if (hyp_pmd_table_empty(start_pmd)) - clear_hyp_pud_entry(pud); -} - -static void unmap_hyp_puds(p4d_t *p4d, phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t next; - pud_t *pud, *start_pud; - - start_pud = pud = pud_offset(p4d, addr); - do { - next = pud_addr_end(addr, end); - /* Hyp doesn't use huge puds */ - if (!pud_none(*pud)) - unmap_hyp_pmds(pud, addr, next); - } while (pud++, addr = next, addr != end); - - if (hyp_pud_table_empty(start_pud)) - clear_hyp_p4d_entry(p4d); -} - -static void unmap_hyp_p4ds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end) -{ - phys_addr_t next; - p4d_t *p4d, *start_p4d; - - start_p4d = p4d = p4d_offset(pgd, addr); - do { - next = p4d_addr_end(addr, end); - /* Hyp doesn't use huge p4ds */ - if (!p4d_none(*p4d)) - unmap_hyp_puds(p4d, addr, next); - } while (p4d++, addr = next, addr != end); - - if (hyp_p4d_table_empty(start_p4d)) - clear_hyp_pgd_entry(pgd); -} - -static unsigned int kvm_pgd_index(unsigned long addr, unsigned int ptrs_per_pgd) -{ - return (addr >> PGDIR_SHIFT) & (ptrs_per_pgd - 1); -} - -static void __unmap_hyp_range(pgd_t *pgdp, unsigned long ptrs_per_pgd, - phys_addr_t start, u64 size) -{ - pgd_t *pgd; - phys_addr_t addr = start, end = start + size; - phys_addr_t next; - - /* - * We don't unmap anything from HYP, except at the hyp tear down. - * Hence, we don't have to invalidate the TLBs here. - */ - pgd = pgdp + kvm_pgd_index(addr, ptrs_per_pgd); - do { - next = pgd_addr_end(addr, end); - if (!pgd_none(*pgd)) - unmap_hyp_p4ds(pgd, addr, next); - } while (pgd++, addr = next, addr != end); -} - -static void unmap_hyp_range(pgd_t *pgdp, phys_addr_t start, u64 size) -{ - __unmap_hyp_range(pgdp, PTRS_PER_PGD, start, size); -} - -static void unmap_hyp_idmap_range(pgd_t *pgdp, phys_addr_t start, u64 size) -{ - __unmap_hyp_range(pgdp, __kvm_idmap_ptrs_per_pgd(), start, size); -} - /** * free_hyp_pgds - free Hyp-mode page tables - * - * Assumes hyp_pgd is a page table used strictly in Hyp-mode and - * therefore contains either mappings in the kernel memory area (above - * PAGE_OFFSET), or device mappings in the idmap range. - * - * boot_hyp_pgd should only map the idmap range, and is only used in - * the extended idmap case. */ void free_hyp_pgds(void) { - pgd_t *id_pgd; - mutex_lock(&kvm_hyp_pgd_mutex); - - id_pgd = boot_hyp_pgd ? boot_hyp_pgd : hyp_pgd; - - if (id_pgd) { - /* In case we never called hyp_mmu_init() */ - if (!io_map_base) - io_map_base = hyp_idmap_start; - unmap_hyp_idmap_range(id_pgd, io_map_base, - hyp_idmap_start + PAGE_SIZE - io_map_base); + if (hyp_pgtable) { + kvm_pgtable_hyp_destroy(hyp_pgtable); + kfree(hyp_pgtable); } - - if (boot_hyp_pgd) { - free_pages((unsigned long)boot_hyp_pgd, hyp_pgd_order); - boot_hyp_pgd = NULL; - } - - if (hyp_pgd) { - unmap_hyp_range(hyp_pgd, kern_hyp_va(PAGE_OFFSET), - (uintptr_t)high_memory - PAGE_OFFSET); - - free_pages((unsigned long)hyp_pgd, hyp_pgd_order); - hyp_pgd = NULL; - } - if (merged_hyp_pgd) { - clear_page(merged_hyp_pgd); - free_page((unsigned long)merged_hyp_pgd); - merged_hyp_pgd = NULL; - } - mutex_unlock(&kvm_hyp_pgd_mutex); } -static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start, - unsigned long end, unsigned long pfn, - pgprot_t prot) -{ - pte_t *pte; - unsigned long addr; - - addr = start; - do { - pte = pte_offset_kernel(pmd, addr); - kvm_set_pte(pte, kvm_pfn_pte(pfn, prot)); - get_page(virt_to_page(pte)); - pfn++; - } while (addr += PAGE_SIZE, addr != end); -} - -static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start, - unsigned long end, unsigned long pfn, - pgprot_t prot) -{ - pmd_t *pmd; - pte_t *pte; - unsigned long addr, next; - - addr = start; - do { - pmd = pmd_offset(pud, addr); - - BUG_ON(pmd_sect(*pmd)); - - if (pmd_none(*pmd)) { - pte = pte_alloc_one_kernel(NULL); - if (!pte) { - kvm_err("Cannot allocate Hyp pte\n"); - return -ENOMEM; - } - kvm_pmd_populate(pmd, pte); - get_page(virt_to_page(pmd)); - } - - next = pmd_addr_end(addr, end); - - create_hyp_pte_mappings(pmd, addr, next, pfn, prot); - pfn += (next - addr) >> PAGE_SHIFT; - } while (addr = next, addr != end); - - return 0; -} - -static int create_hyp_pud_mappings(p4d_t *p4d, unsigned long start, - unsigned long end, unsigned long pfn, - pgprot_t prot) -{ - pud_t *pud; - pmd_t *pmd; - unsigned long addr, next; - int ret; - - addr = start; - do { - pud = pud_offset(p4d, addr); - - if (pud_none_or_clear_bad(pud)) { - pmd = pmd_alloc_one(NULL, addr); - if (!pmd) { - kvm_err("Cannot allocate Hyp pmd\n"); - return -ENOMEM; - } - kvm_pud_populate(pud, pmd); - get_page(virt_to_page(pud)); - } - - next = pud_addr_end(addr, end); - ret = create_hyp_pmd_mappings(pud, addr, next, pfn, prot); - if (ret) - return ret; - pfn += (next - addr) >> PAGE_SHIFT; - } while (addr = next, addr != end); - - return 0; -} - -static int create_hyp_p4d_mappings(pgd_t *pgd, unsigned long start, - unsigned long end, unsigned long pfn, - pgprot_t prot) +static int __create_hyp_mappings(unsigned long start, unsigned long size, + unsigned long phys, enum kvm_pgtable_prot prot) { - p4d_t *p4d; - pud_t *pud; - unsigned long addr, next; - int ret; - - addr = start; - do { - p4d = p4d_offset(pgd, addr); - - if (p4d_none(*p4d)) { - pud = pud_alloc_one(NULL, addr); - if (!pud) { - kvm_err("Cannot allocate Hyp pud\n"); - return -ENOMEM; - } - kvm_p4d_populate(p4d, pud); - get_page(virt_to_page(p4d)); - } - - next = p4d_addr_end(addr, end); - ret = create_hyp_pud_mappings(p4d, addr, next, pfn, prot); - if (ret) - return ret; - pfn += (next - addr) >> PAGE_SHIFT; - } while (addr = next, addr != end); - - return 0; -} - -static int __create_hyp_mappings(pgd_t *pgdp, unsigned long ptrs_per_pgd, - unsigned long start, unsigned long end, - unsigned long pfn, pgprot_t prot) -{ - pgd_t *pgd; - p4d_t *p4d; - unsigned long addr, next; - int err = 0; + int err; mutex_lock(&kvm_hyp_pgd_mutex); - addr = start & PAGE_MASK; - end = PAGE_ALIGN(end); - do { - pgd = pgdp + kvm_pgd_index(addr, ptrs_per_pgd); - - if (pgd_none(*pgd)) { - p4d = p4d_alloc_one(NULL, addr); - if (!p4d) { - kvm_err("Cannot allocate Hyp p4d\n"); - err = -ENOMEM; - goto out; - } - kvm_pgd_populate(pgd, p4d); - get_page(virt_to_page(pgd)); - } - - next = pgd_addr_end(addr, end); - err = create_hyp_p4d_mappings(pgd, addr, next, pfn, prot); - if (err) - goto out; - pfn += (next - addr) >> PAGE_SHIFT; - } while (addr = next, addr != end); -out: + err = kvm_pgtable_hyp_map(hyp_pgtable, start, size, phys, prot); mutex_unlock(&kvm_hyp_pgd_mutex); + return err; } @@ -845,7 +220,7 @@ static phys_addr_t kvm_kaddr_to_phys(void *kaddr) * in Hyp-mode mapping (modulo HYP_PAGE_OFFSET) to the same underlying * physical pages. */ -int create_hyp_mappings(void *from, void *to, pgprot_t prot) +int create_hyp_mappings(void *from, void *to, enum kvm_pgtable_prot prot) { phys_addr_t phys_addr; unsigned long virt_addr; @@ -862,9 +237,7 @@ int create_hyp_mappings(void *from, void *to, pgprot_t prot) int err; phys_addr = kvm_kaddr_to_phys(from + virt_addr - start); - err = __create_hyp_mappings(hyp_pgd, PTRS_PER_PGD, - virt_addr, virt_addr + PAGE_SIZE, - __phys_to_pfn(phys_addr), + err = __create_hyp_mappings(virt_addr, PAGE_SIZE, phys_addr, prot); if (err) return err; @@ -874,9 +247,9 @@ int create_hyp_mappings(void *from, void *to, pgprot_t prot) } static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, - unsigned long *haddr, pgprot_t prot) + unsigned long *haddr, + enum kvm_pgtable_prot prot) { - pgd_t *pgd = hyp_pgd; unsigned long base; int ret = 0; @@ -908,17 +281,11 @@ static int __create_hyp_private_mapping(phys_addr_t phys_addr, size_t size, if (ret) goto out; - if (__kvm_cpu_uses_extended_idmap()) - pgd = boot_hyp_pgd; - - ret = __create_hyp_mappings(pgd, __kvm_idmap_ptrs_per_pgd(), - base, base + size, - __phys_to_pfn(phys_addr), prot); + ret = __create_hyp_mappings(base, size, phys_addr, prot); if (ret) goto out; *haddr = base + offset_in_page(phys_addr); - out: return ret; } @@ -989,47 +356,48 @@ int create_hyp_exec_mappings(phys_addr_t phys_addr, size_t size, * @kvm: The pointer to the KVM structure * @mmu: The pointer to the s2 MMU structure * - * Allocates only the stage-2 HW PGD level table(s) of size defined by - * stage2_pgd_size(mmu->kvm). - * + * Allocates only the stage-2 HW PGD level table(s). * Note we don't need locking here as this is only called when the VM is * created, which can only be done once. */ int kvm_init_stage2_mmu(struct kvm *kvm, struct kvm_s2_mmu *mmu) { - phys_addr_t pgd_phys; - pgd_t *pgd; - int cpu; + int cpu, err; + struct kvm_pgtable *pgt; - if (mmu->pgd != NULL) { + if (mmu->pgt != NULL) { kvm_err("kvm_arch already initialized?\n"); return -EINVAL; } - /* Allocate the HW PGD, making sure that each page gets its own refcount */ - pgd = alloc_pages_exact(stage2_pgd_size(kvm), GFP_KERNEL | __GFP_ZERO); - if (!pgd) + pgt = kzalloc(sizeof(*pgt), GFP_KERNEL); + if (!pgt) return -ENOMEM; - pgd_phys = virt_to_phys(pgd); - if (WARN_ON(pgd_phys & ~kvm_vttbr_baddr_mask(kvm))) - return -EINVAL; + err = kvm_pgtable_stage2_init(pgt, kvm); + if (err) + goto out_free_pgtable; mmu->last_vcpu_ran = alloc_percpu(typeof(*mmu->last_vcpu_ran)); if (!mmu->last_vcpu_ran) { - free_pages_exact(pgd, stage2_pgd_size(kvm)); - return -ENOMEM; + err = -ENOMEM; + goto out_destroy_pgtable; } for_each_possible_cpu(cpu) *per_cpu_ptr(mmu->last_vcpu_ran, cpu) = -1; mmu->kvm = kvm; - mmu->pgd = pgd; - mmu->pgd_phys = pgd_phys; + mmu->pgt = pgt; + mmu->pgd_phys = __pa(pgt->pgd); mmu->vmid.vmid_gen = 0; - return 0; + +out_destroy_pgtable: + kvm_pgtable_stage2_destroy(pgt); +out_free_pgtable: + kfree(pgt); + return err; } static void stage2_unmap_memslot(struct kvm *kvm, @@ -1102,363 +470,21 @@ void stage2_unmap_vm(struct kvm *kvm) void kvm_free_stage2_pgd(struct kvm_s2_mmu *mmu) { struct kvm *kvm = mmu->kvm; - void *pgd = NULL; + struct kvm_pgtable *pgt = NULL; spin_lock(&kvm->mmu_lock); - if (mmu->pgd) { - unmap_stage2_range(mmu, 0, kvm_phys_size(kvm)); - pgd = READ_ONCE(mmu->pgd); - mmu->pgd = NULL; - } - spin_unlock(&kvm->mmu_lock); - - /* Free the HW pgd, one page at a time */ - if (pgd) { - free_pages_exact(pgd, stage2_pgd_size(kvm)); + pgt = mmu->pgt; + if (pgt) { + mmu->pgd_phys = 0; + mmu->pgt = NULL; free_percpu(mmu->last_vcpu_ran); } -} - -static p4d_t *stage2_get_p4d(struct kvm_s2_mmu *mmu, struct kvm_mmu_memory_cache *cache, - phys_addr_t addr) -{ - struct kvm *kvm = mmu->kvm; - pgd_t *pgd; - p4d_t *p4d; - - pgd = mmu->pgd + stage2_pgd_index(kvm, addr); - if (stage2_pgd_none(kvm, *pgd)) { - if (!cache) - return NULL; - p4d = kvm_mmu_memory_cache_alloc(cache); - stage2_pgd_populate(kvm, pgd, p4d); - get_page(virt_to_page(pgd)); - } - - return stage2_p4d_offset(kvm, pgd, addr); -} - -static pud_t *stage2_get_pud(struct kvm_s2_mmu *mmu, struct kvm_mmu_memory_cache *cache, - phys_addr_t addr) -{ - struct kvm *kvm = mmu->kvm; - p4d_t *p4d; - pud_t *pud; - - p4d = stage2_get_p4d(mmu, cache, addr); - if (stage2_p4d_none(kvm, *p4d)) { - if (!cache) - return NULL; - pud = kvm_mmu_memory_cache_alloc(cache); - stage2_p4d_populate(kvm, p4d, pud); - get_page(virt_to_page(p4d)); - } - - return stage2_pud_offset(kvm, p4d, addr); -} - -static pmd_t *stage2_get_pmd(struct kvm_s2_mmu *mmu, struct kvm_mmu_memory_cache *cache, - phys_addr_t addr) -{ - struct kvm *kvm = mmu->kvm; - pud_t *pud; - pmd_t *pmd; - - pud = stage2_get_pud(mmu, cache, addr); - if (!pud || stage2_pud_huge(kvm, *pud)) - return NULL; - - if (stage2_pud_none(kvm, *pud)) { - if (!cache) - return NULL; - pmd = kvm_mmu_memory_cache_alloc(cache); - stage2_pud_populate(kvm, pud, pmd); - get_page(virt_to_page(pud)); - } - - return stage2_pmd_offset(kvm, pud, addr); -} - -static int stage2_set_pmd_huge(struct kvm_s2_mmu *mmu, - struct kvm_mmu_memory_cache *cache, - phys_addr_t addr, const pmd_t *new_pmd) -{ - pmd_t *pmd, old_pmd; - -retry: - pmd = stage2_get_pmd(mmu, cache, addr); - VM_BUG_ON(!pmd); - - old_pmd = *pmd; - /* - * Multiple vcpus faulting on the same PMD entry, can - * lead to them sequentially updating the PMD with the - * same value. Following the break-before-make - * (pmd_clear() followed by tlb_flush()) process can - * hinder forward progress due to refaults generated - * on missing translations. - * - * Skip updating the page table if the entry is - * unchanged. - */ - if (pmd_val(old_pmd) == pmd_val(*new_pmd)) - return 0; - - if (pmd_present(old_pmd)) { - /* - * If we already have PTE level mapping for this block, - * we must unmap it to avoid inconsistent TLB state and - * leaking the table page. We could end up in this situation - * if the memory slot was marked for dirty logging and was - * reverted, leaving PTE level mappings for the pages accessed - * during the period. So, unmap the PTE level mapping for this - * block and retry, as we could have released the upper level - * table in the process. - * - * Normal THP split/merge follows mmu_notifier callbacks and do - * get handled accordingly. - */ - if (!pmd_thp_or_huge(old_pmd)) { - unmap_stage2_range(mmu, addr & S2_PMD_MASK, S2_PMD_SIZE); - goto retry; - } - /* - * Mapping in huge pages should only happen through a - * fault. If a page is merged into a transparent huge - * page, the individual subpages of that huge page - * should be unmapped through MMU notifiers before we - * get here. - * - * Merging of CompoundPages is not supported; they - * should become splitting first, unmapped, merged, - * and mapped back in on-demand. - */ - WARN_ON_ONCE(pmd_pfn(old_pmd) != pmd_pfn(*new_pmd)); - pmd_clear(pmd); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PMD_LEVEL); - } else { - get_page(virt_to_page(pmd)); - } - - kvm_set_pmd(pmd, *new_pmd); - return 0; -} - -static int stage2_set_pud_huge(struct kvm_s2_mmu *mmu, - struct kvm_mmu_memory_cache *cache, - phys_addr_t addr, const pud_t *new_pudp) -{ - struct kvm *kvm = mmu->kvm; - pud_t *pudp, old_pud; - -retry: - pudp = stage2_get_pud(mmu, cache, addr); - VM_BUG_ON(!pudp); - - old_pud = *pudp; - - /* - * A large number of vcpus faulting on the same stage 2 entry, - * can lead to a refault due to the stage2_pud_clear()/tlb_flush(). - * Skip updating the page tables if there is no change. - */ - if (pud_val(old_pud) == pud_val(*new_pudp)) - return 0; - - if (stage2_pud_present(kvm, old_pud)) { - /* - * If we already have table level mapping for this block, unmap - * the range for this block and retry. - */ - if (!stage2_pud_huge(kvm, old_pud)) { - unmap_stage2_range(mmu, addr & S2_PUD_MASK, S2_PUD_SIZE); - goto retry; - } - - WARN_ON_ONCE(kvm_pud_pfn(old_pud) != kvm_pud_pfn(*new_pudp)); - stage2_pud_clear(kvm, pudp); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PUD_LEVEL); - } else { - get_page(virt_to_page(pudp)); - } - - kvm_set_pud(pudp, *new_pudp); - return 0; -} - -/* - * stage2_get_leaf_entry - walk the stage2 VM page tables and return - * true if a valid and present leaf-entry is found. A pointer to the - * leaf-entry is returned in the appropriate level variable - pudpp, - * pmdpp, ptepp. - */ -static bool stage2_get_leaf_entry(struct kvm_s2_mmu *mmu, phys_addr_t addr, - pud_t **pudpp, pmd_t **pmdpp, pte_t **ptepp) -{ - struct kvm *kvm = mmu->kvm; - pud_t *pudp; - pmd_t *pmdp; - pte_t *ptep; - - *pudpp = NULL; - *pmdpp = NULL; - *ptepp = NULL; - - pudp = stage2_get_pud(mmu, NULL, addr); - if (!pudp || stage2_pud_none(kvm, *pudp) || !stage2_pud_present(kvm, *pudp)) - return false; - - if (stage2_pud_huge(kvm, *pudp)) { - *pudpp = pudp; - return true; - } - - pmdp = stage2_pmd_offset(kvm, pudp, addr); - if (!pmdp || pmd_none(*pmdp) || !pmd_present(*pmdp)) - return false; - - if (pmd_thp_or_huge(*pmdp)) { - *pmdpp = pmdp; - return true; - } - - ptep = pte_offset_kernel(pmdp, addr); - if (!ptep || pte_none(*ptep) || !pte_present(*ptep)) - return false; - - *ptepp = ptep; - return true; -} - -static bool stage2_is_exec(struct kvm_s2_mmu *mmu, phys_addr_t addr, unsigned long sz) -{ - pud_t *pudp; - pmd_t *pmdp; - pte_t *ptep; - bool found; - - found = stage2_get_leaf_entry(mmu, addr, &pudp, &pmdp, &ptep); - if (!found) - return false; - - if (pudp) - return sz <= PUD_SIZE && kvm_s2pud_exec(pudp); - else if (pmdp) - return sz <= PMD_SIZE && kvm_s2pmd_exec(pmdp); - else - return sz == PAGE_SIZE && kvm_s2pte_exec(ptep); -} - -static int stage2_set_pte(struct kvm_s2_mmu *mmu, - struct kvm_mmu_memory_cache *cache, - phys_addr_t addr, const pte_t *new_pte, - unsigned long flags) -{ - struct kvm *kvm = mmu->kvm; - pud_t *pud; - pmd_t *pmd; - pte_t *pte, old_pte; - bool iomap = flags & KVM_S2PTE_FLAG_IS_IOMAP; - bool logging_active = flags & KVM_S2_FLAG_LOGGING_ACTIVE; - - VM_BUG_ON(logging_active && !cache); - - /* Create stage-2 page table mapping - Levels 0 and 1 */ - pud = stage2_get_pud(mmu, cache, addr); - if (!pud) { - /* - * Ignore calls from kvm_set_spte_hva for unallocated - * address ranges. - */ - return 0; - } - - /* - * While dirty page logging - dissolve huge PUD, then continue - * on to allocate page. - */ - if (logging_active) - stage2_dissolve_pud(mmu, addr, pud); - - if (stage2_pud_none(kvm, *pud)) { - if (!cache) - return 0; /* ignore calls from kvm_set_spte_hva */ - pmd = kvm_mmu_memory_cache_alloc(cache); - stage2_pud_populate(kvm, pud, pmd); - get_page(virt_to_page(pud)); - } - - pmd = stage2_pmd_offset(kvm, pud, addr); - if (!pmd) { - /* - * Ignore calls from kvm_set_spte_hva for unallocated - * address ranges. - */ - return 0; - } - - /* - * While dirty page logging - dissolve huge PMD, then continue on to - * allocate page. - */ - if (logging_active) - stage2_dissolve_pmd(mmu, addr, pmd); - - /* Create stage-2 page mappings - Level 2 */ - if (pmd_none(*pmd)) { - if (!cache) - return 0; /* ignore calls from kvm_set_spte_hva */ - pte = kvm_mmu_memory_cache_alloc(cache); - kvm_pmd_populate(pmd, pte); - get_page(virt_to_page(pmd)); - } - - pte = pte_offset_kernel(pmd, addr); - - if (iomap && pte_present(*pte)) - return -EFAULT; - - /* Create 2nd stage page table mapping - Level 3 */ - old_pte = *pte; - if (pte_present(old_pte)) { - /* Skip page table update if there is no change */ - if (pte_val(old_pte) == pte_val(*new_pte)) - return 0; - - kvm_set_pte(pte, __pte(0)); - kvm_tlb_flush_vmid_ipa(mmu, addr, S2_PTE_LEVEL); - } else { - get_page(virt_to_page(pte)); - } - - kvm_set_pte(pte, *new_pte); - return 0; -} + spin_unlock(&kvm->mmu_lock); -#ifndef __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG -static int stage2_ptep_test_and_clear_young(pte_t *pte) -{ - if (pte_young(*pte)) { - *pte = pte_mkold(*pte); - return 1; + if (pgt) { + kvm_pgtable_stage2_destroy(pgt); + kfree(pgt); } - return 0; -} -#else -static int stage2_ptep_test_and_clear_young(pte_t *pte) -{ - return __ptep_test_and_clear_young(pte); -} -#endif - -static int stage2_pmdp_test_and_clear_young(pmd_t *pmd) -{ - return stage2_ptep_test_and_clear_young((pte_t *)pmd); -} - -static int stage2_pudp_test_and_clear_young(pud_t *pud) -{ - return stage2_ptep_test_and_clear_young((pte_t *)pud); } /** @@ -1468,169 +494,52 @@ static int stage2_pudp_test_and_clear_young(pud_t *pud) * @guest_ipa: The IPA at which to insert the mapping * @pa: The physical address of the device * @size: The size of the mapping + * @writable: Whether or not to create a writable mapping */ int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa, phys_addr_t pa, unsigned long size, bool writable) { - phys_addr_t addr, end; + phys_addr_t addr; int ret = 0; - unsigned long pfn; struct kvm_mmu_memory_cache cache = { 0, __GFP_ZERO, NULL, }; + struct kvm_pgtable *pgt = kvm->arch.mmu.pgt; + enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_DEVICE | + KVM_PGTABLE_PROT_R | + (writable ? KVM_PGTABLE_PROT_W : 0); - end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK; - pfn = __phys_to_pfn(pa); - - for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) { - pte_t pte = kvm_pfn_pte(pfn, PAGE_S2_DEVICE); - - if (writable) - pte = kvm_s2pte_mkwrite(pte); + size += offset_in_page(guest_ipa); + guest_ipa &= PAGE_MASK; + for (addr = guest_ipa; addr < guest_ipa + size; addr += PAGE_SIZE) { ret = kvm_mmu_topup_memory_cache(&cache, kvm_mmu_cache_min_pages(kvm)); if (ret) - goto out; + break; + spin_lock(&kvm->mmu_lock); - ret = stage2_set_pte(&kvm->arch.mmu, &cache, addr, &pte, - KVM_S2PTE_FLAG_IS_IOMAP); + ret = kvm_pgtable_stage2_map(pgt, addr, PAGE_SIZE, pa, prot, + &cache); spin_unlock(&kvm->mmu_lock); if (ret) - goto out; + break; - pfn++; + pa += PAGE_SIZE; } -out: kvm_mmu_free_memory_cache(&cache); return ret; } /** - * stage2_wp_ptes - write protect PMD range - * @pmd: pointer to pmd entry - * @addr: range start address - * @end: range end address - */ -static void stage2_wp_ptes(pmd_t *pmd, phys_addr_t addr, phys_addr_t end) -{ - pte_t *pte; - - pte = pte_offset_kernel(pmd, addr); - do { - if (!pte_none(*pte)) { - if (!kvm_s2pte_readonly(pte)) - kvm_set_s2pte_readonly(pte); - } - } while (pte++, addr += PAGE_SIZE, addr != end); -} - -/** - * stage2_wp_pmds - write protect PUD range - * kvm: kvm instance for the VM - * @pud: pointer to pud entry - * @addr: range start address - * @end: range end address - */ -static void stage2_wp_pmds(struct kvm_s2_mmu *mmu, pud_t *pud, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - pmd_t *pmd; - phys_addr_t next; - - pmd = stage2_pmd_offset(kvm, pud, addr); - - do { - next = stage2_pmd_addr_end(kvm, addr, end); - if (!pmd_none(*pmd)) { - if (pmd_thp_or_huge(*pmd)) { - if (!kvm_s2pmd_readonly(pmd)) - kvm_set_s2pmd_readonly(pmd); - } else { - stage2_wp_ptes(pmd, addr, next); - } - } - } while (pmd++, addr = next, addr != end); -} - -/** - * stage2_wp_puds - write protect P4D range - * @p4d: pointer to p4d entry - * @addr: range start address - * @end: range end address - */ -static void stage2_wp_puds(struct kvm_s2_mmu *mmu, p4d_t *p4d, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - pud_t *pud; - phys_addr_t next; - - pud = stage2_pud_offset(kvm, p4d, addr); - do { - next = stage2_pud_addr_end(kvm, addr, end); - if (!stage2_pud_none(kvm, *pud)) { - if (stage2_pud_huge(kvm, *pud)) { - if (!kvm_s2pud_readonly(pud)) - kvm_set_s2pud_readonly(pud); - } else { - stage2_wp_pmds(mmu, pud, addr, next); - } - } - } while (pud++, addr = next, addr != end); -} - -/** - * stage2_wp_p4ds - write protect PGD range - * @pgd: pointer to pgd entry - * @addr: range start address - * @end: range end address - */ -static void stage2_wp_p4ds(struct kvm_s2_mmu *mmu, pgd_t *pgd, - phys_addr_t addr, phys_addr_t end) -{ - struct kvm *kvm = mmu->kvm; - p4d_t *p4d; - phys_addr_t next; - - p4d = stage2_p4d_offset(kvm, pgd, addr); - do { - next = stage2_p4d_addr_end(kvm, addr, end); - if (!stage2_p4d_none(kvm, *p4d)) - stage2_wp_puds(mmu, p4d, addr, next); - } while (p4d++, addr = next, addr != end); -} - -/** * stage2_wp_range() - write protect stage2 memory region range - * @kvm: The KVM pointer + * @mmu: The KVM stage-2 MMU pointer * @addr: Start address of range * @end: End address of range */ static void stage2_wp_range(struct kvm_s2_mmu *mmu, phys_addr_t addr, phys_addr_t end) { struct kvm *kvm = mmu->kvm; - pgd_t *pgd; - phys_addr_t next; - - pgd = mmu->pgd + stage2_pgd_index(kvm, addr); - do { - /* - * Release kvm_mmu_lock periodically if the memory region is - * large. Otherwise, we may see kernel panics with - * CONFIG_DETECT_HUNG_TASK, CONFIG_LOCKUP_DETECTOR, - * CONFIG_LOCKDEP. Additionally, holding the lock too long - * will also starve other vCPUs. We have to also make sure - * that the page tables are not freed while we released - * the lock. - */ - cond_resched_lock(&kvm->mmu_lock); - if (!READ_ONCE(mmu->pgd)) - break; - next = stage2_pgd_addr_end(kvm, addr, end); - if (stage2_pgd_present(kvm, *pgd)) - stage2_wp_p4ds(mmu, pgd, addr, next); - } while (pgd++, addr = next, addr != end); + stage2_apply_range_resched(kvm, addr, end, kvm_pgtable_stage2_wrprotect); } /** @@ -1833,20 +742,21 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, struct kvm_memory_slot *memslot, unsigned long hva, unsigned long fault_status) { - int ret; + int ret = 0; bool write_fault, writable, force_pte = false; - bool exec_fault, needs_exec; + bool exec_fault; + bool device = false; unsigned long mmu_seq; - gfn_t gfn = fault_ipa >> PAGE_SHIFT; struct kvm *kvm = vcpu->kvm; struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache; struct vm_area_struct *vma; short vma_shift; + gfn_t gfn; kvm_pfn_t pfn; - pgprot_t mem_type = PAGE_S2; bool logging_active = memslot_is_logging(memslot); - unsigned long vma_pagesize, flags = 0; - struct kvm_s2_mmu *mmu = vcpu->arch.hw_mmu; + unsigned long vma_pagesize; + enum kvm_pgtable_prot prot = KVM_PGTABLE_PROT_R; + struct kvm_pgtable *pgt; write_fault = kvm_is_write_fault(vcpu); exec_fault = kvm_vcpu_trap_is_exec_fault(vcpu); @@ -1871,31 +781,41 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, else vma_shift = PAGE_SHIFT; - vma_pagesize = 1ULL << vma_shift; if (logging_active || - (vma->vm_flags & VM_PFNMAP) || - !fault_supports_stage2_huge_mapping(memslot, hva, vma_pagesize)) { + (vma->vm_flags & VM_PFNMAP)) { force_pte = true; - vma_pagesize = PAGE_SIZE; vma_shift = PAGE_SHIFT; } - /* - * The stage2 has a minimum of 2 level table (For arm64 see - * kvm_arm_setup_stage2()). Hence, we are guaranteed that we can - * use PMD_SIZE huge mappings (even when the PMD is folded into PGD). - * As for PUD huge maps, we must make sure that we have at least - * 3 levels, i.e, PMD is not folded. - */ - if (vma_pagesize == PMD_SIZE || - (vma_pagesize == PUD_SIZE && kvm_stage2_has_pmd(kvm))) - gfn = (fault_ipa & huge_page_mask(hstate_vma(vma))) >> PAGE_SHIFT; + if (vma_shift == PUD_SHIFT && + !fault_supports_stage2_huge_mapping(memslot, hva, PUD_SIZE)) + vma_shift = PMD_SHIFT; + + if (vma_shift == PMD_SHIFT && + !fault_supports_stage2_huge_mapping(memslot, hva, PMD_SIZE)) { + force_pte = true; + vma_shift = PAGE_SHIFT; + } + + vma_pagesize = 1UL << vma_shift; + if (vma_pagesize == PMD_SIZE || vma_pagesize == PUD_SIZE) + fault_ipa &= ~(vma_pagesize - 1); + + gfn = fault_ipa >> PAGE_SHIFT; mmap_read_unlock(current->mm); - /* We need minimum second+third level pages */ - ret = kvm_mmu_topup_memory_cache(memcache, kvm_mmu_cache_min_pages(kvm)); - if (ret) - return ret; + /* + * Permission faults just need to update the existing leaf entry, + * and so normally don't require allocations from the memcache. The + * only exception to this is when dirty logging is enabled at runtime + * and a write fault needs to collapse a block entry into a table. + */ + if (fault_status != FSC_PERM || (logging_active && write_fault)) { + ret = kvm_mmu_topup_memory_cache(memcache, + kvm_mmu_cache_min_pages(kvm)); + if (ret) + return ret; + } mmu_seq = vcpu->kvm->mmu_notifier_seq; /* @@ -1918,28 +838,20 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, return -EFAULT; if (kvm_is_device_pfn(pfn)) { - mem_type = PAGE_S2_DEVICE; - flags |= KVM_S2PTE_FLAG_IS_IOMAP; - } else if (logging_active) { - /* - * Faults on pages in a memslot with logging enabled - * should not be mapped with huge pages (it introduces churn - * and performance degradation), so force a pte mapping. - */ - flags |= KVM_S2_FLAG_LOGGING_ACTIVE; - + device = true; + } else if (logging_active && !write_fault) { /* * Only actually map the page as writable if this was a write * fault. */ - if (!write_fault) - writable = false; + writable = false; } - if (exec_fault && is_iomap(flags)) + if (exec_fault && device) return -ENOEXEC; spin_lock(&kvm->mmu_lock); + pgt = vcpu->arch.hw_mmu->pgt; if (mmu_notifier_retry(kvm, mmu_seq)) goto out_unlock; @@ -1950,67 +862,31 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa, if (vma_pagesize == PAGE_SIZE && !force_pte) vma_pagesize = transparent_hugepage_adjust(memslot, hva, &pfn, &fault_ipa); - if (writable) + if (writable) { + prot |= KVM_PGTABLE_PROT_W; kvm_set_pfn_dirty(pfn); + mark_page_dirty(kvm, gfn); + } - if (fault_status != FSC_PERM && !is_iomap(flags)) + if (fault_status != FSC_PERM && !device) clean_dcache_guest_page(pfn, vma_pagesize); - if (exec_fault) + if (exec_fault) { + prot |= KVM_PGTABLE_PROT_X; invalidate_icache_guest_page(pfn, vma_pagesize); + } - /* - * If we took an execution fault we have made the - * icache/dcache coherent above and should now let the s2 - * mapping be executable. - * - * Write faults (!exec_fault && FSC_PERM) are orthogonal to - * execute permissions, and we preserve whatever we have. - */ - needs_exec = exec_fault || - (fault_status == FSC_PERM && - stage2_is_exec(mmu, fault_ipa, vma_pagesize)); - - /* - * If PUD_SIZE == PMD_SIZE, there is no real PUD level, and - * all we have is a 2-level page table. Trying to map a PUD in - * this case would be fatally wrong. - */ - if (PUD_SIZE != PMD_SIZE && vma_pagesize == PUD_SIZE) { - pud_t new_pud = kvm_pfn_pud(pfn, mem_type); - - new_pud = kvm_pud_mkhuge(new_pud); - if (writable) - new_pud = kvm_s2pud_mkwrite(new_pud); - - if (needs_exec) - new_pud = kvm_s2pud_mkexec(new_pud); - - ret = stage2_set_pud_huge(mmu, memcache, fault_ipa, &new_pud); - } else if (vma_pagesize == PMD_SIZE) { - pmd_t new_pmd = kvm_pfn_pmd(pfn, mem_type); - - new_pmd = kvm_pmd_mkhuge(new_pmd); - - if (writable) - new_pmd = kvm_s2pmd_mkwrite(new_pmd); - - if (needs_exec) - new_pmd = kvm_s2pmd_mkexec(new_pmd); + if (device) + prot |= KVM_PGTABLE_PROT_DEVICE; + else if (cpus_have_const_cap(ARM64_HAS_CACHE_DIC)) + prot |= KVM_PGTABLE_PROT_X; - ret = stage2_set_pmd_huge(mmu, memcache, fault_ipa, &new_pmd); + if (fault_status == FSC_PERM && !(logging_active && writable)) { + ret = kvm_pgtable_stage2_relax_perms(pgt, fault_ipa, prot); } else { - pte_t new_pte = kvm_pfn_pte(pfn, mem_type); - - if (writable) { - new_pte = kvm_s2pte_mkwrite(new_pte); - mark_page_dirty(kvm, gfn); - } - - if (needs_exec) - new_pte = kvm_s2pte_mkexec(new_pte); - - ret = stage2_set_pte(mmu, memcache, fault_ipa, &new_pte, flags); + ret = kvm_pgtable_stage2_map(pgt, fault_ipa, vma_pagesize, + __pfn_to_phys(pfn), prot, + memcache); } out_unlock: @@ -2020,46 +896,23 @@ out_unlock: return ret; } -/* - * Resolve the access fault by making the page young again. - * Note that because the faulting entry is guaranteed not to be - * cached in the TLB, we don't need to invalidate anything. - * Only the HW Access Flag updates are supported for Stage 2 (no DBM), - * so there is no need for atomic (pte|pmd)_mkyoung operations. - */ +/* Resolve the access fault by making the page young again. */ static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa) { - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - kvm_pfn_t pfn; - bool pfn_valid = false; + pte_t pte; + kvm_pte_t kpte; + struct kvm_s2_mmu *mmu; trace_kvm_access_fault(fault_ipa); spin_lock(&vcpu->kvm->mmu_lock); - - if (!stage2_get_leaf_entry(vcpu->arch.hw_mmu, fault_ipa, &pud, &pmd, &pte)) - goto out; - - if (pud) { /* HugeTLB */ - *pud = kvm_s2pud_mkyoung(*pud); - pfn = kvm_pud_pfn(*pud); - pfn_valid = true; - } else if (pmd) { /* THP, HugeTLB */ - *pmd = pmd_mkyoung(*pmd); - pfn = pmd_pfn(*pmd); - pfn_valid = true; - } else { - *pte = pte_mkyoung(*pte); /* Just a page... */ - pfn = pte_pfn(*pte); - pfn_valid = true; - } - -out: + mmu = vcpu->arch.hw_mmu; + kpte = kvm_pgtable_stage2_mkyoung(mmu->pgt, fault_ipa); spin_unlock(&vcpu->kvm->mmu_lock); - if (pfn_valid) - kvm_set_pfn_accessed(pfn); + + pte = __pte(kpte); + if (pte_valid(pte)) + kvm_set_pfn_accessed(pte_pfn(pte)); } /** @@ -2230,7 +1083,7 @@ static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *dat int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end, unsigned flags) { - if (!kvm->arch.mmu.pgd) + if (!kvm->arch.mmu.pgt) return 0; trace_kvm_unmap_hva_range(start, end); @@ -2240,28 +1093,27 @@ int kvm_unmap_hva_range(struct kvm *kvm, static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data) { - pte_t *pte = (pte_t *)data; + kvm_pfn_t *pfn = (kvm_pfn_t *)data; WARN_ON(size != PAGE_SIZE); + /* - * We can always call stage2_set_pte with KVM_S2PTE_FLAG_LOGGING_ACTIVE - * flag clear because MMU notifiers will have unmapped a huge PMD before - * calling ->change_pte() (which in turn calls kvm_set_spte_hva()) and - * therefore stage2_set_pte() never needs to clear out a huge PMD - * through this calling path. + * The MMU notifiers will have unmapped a huge PMD before calling + * ->change_pte() (which in turn calls kvm_set_spte_hva()) and + * therefore we never need to clear out a huge PMD through this + * calling path and a memcache is not required. */ - stage2_set_pte(&kvm->arch.mmu, NULL, gpa, pte, 0); + kvm_pgtable_stage2_map(kvm->arch.mmu.pgt, gpa, PAGE_SIZE, + __pfn_to_phys(*pfn), KVM_PGTABLE_PROT_R, NULL); return 0; } - int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) { unsigned long end = hva + PAGE_SIZE; kvm_pfn_t pfn = pte_pfn(pte); - pte_t stage2_pte; - if (!kvm->arch.mmu.pgd) + if (!kvm->arch.mmu.pgt) return 0; trace_kvm_set_spte_hva(hva); @@ -2271,51 +1123,30 @@ int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) * just like a translation fault and clean the cache to the PoC. */ clean_dcache_guest_page(pfn, PAGE_SIZE); - stage2_pte = kvm_pfn_pte(pfn, PAGE_S2); - handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte); - + handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &pfn); return 0; } static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data) { - pud_t *pud; - pmd_t *pmd; - pte_t *pte; + pte_t pte; + kvm_pte_t kpte; WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - if (!stage2_get_leaf_entry(&kvm->arch.mmu, gpa, &pud, &pmd, &pte)) - return 0; - - if (pud) - return stage2_pudp_test_and_clear_young(pud); - else if (pmd) - return stage2_pmdp_test_and_clear_young(pmd); - else - return stage2_ptep_test_and_clear_young(pte); + kpte = kvm_pgtable_stage2_mkold(kvm->arch.mmu.pgt, gpa); + pte = __pte(kpte); + return pte_valid(pte) && pte_young(pte); } static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, u64 size, void *data) { - pud_t *pud; - pmd_t *pmd; - pte_t *pte; - WARN_ON(size != PAGE_SIZE && size != PMD_SIZE && size != PUD_SIZE); - if (!stage2_get_leaf_entry(&kvm->arch.mmu, gpa, &pud, &pmd, &pte)) - return 0; - - if (pud) - return kvm_s2pud_young(*pud); - else if (pmd) - return pmd_young(*pmd); - else - return pte_young(*pte); + return kvm_pgtable_stage2_is_young(kvm->arch.mmu.pgt, gpa); } int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) { - if (!kvm->arch.mmu.pgd) + if (!kvm->arch.mmu.pgt) return 0; trace_kvm_age_hva(start, end); return handle_hva_to_gpa(kvm, start, end, kvm_age_hva_handler, NULL); @@ -2323,24 +1154,16 @@ int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end) int kvm_test_age_hva(struct kvm *kvm, unsigned long hva) { - if (!kvm->arch.mmu.pgd) + if (!kvm->arch.mmu.pgt) return 0; trace_kvm_test_age_hva(hva); return handle_hva_to_gpa(kvm, hva, hva + PAGE_SIZE, kvm_test_age_hva_handler, NULL); } -void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu) -{ - kvm_mmu_free_memory_cache(&vcpu->arch.mmu_page_cache); -} - phys_addr_t kvm_mmu_get_httbr(void) { - if (__kvm_cpu_uses_extended_idmap()) - return virt_to_phys(merged_hyp_pgd); - else - return virt_to_phys(hyp_pgd); + return __pa(hyp_pgtable->pgd); } phys_addr_t kvm_get_idmap_vector(void) @@ -2348,15 +1171,11 @@ phys_addr_t kvm_get_idmap_vector(void) return hyp_idmap_vector; } -static int kvm_map_idmap_text(pgd_t *pgd) +static int kvm_map_idmap_text(void) { - int err; - - /* Create the idmap in the boot page tables */ - err = __create_hyp_mappings(pgd, __kvm_idmap_ptrs_per_pgd(), - hyp_idmap_start, hyp_idmap_end, - __phys_to_pfn(hyp_idmap_start), - PAGE_HYP_EXEC); + unsigned long size = hyp_idmap_end - hyp_idmap_start; + int err = __create_hyp_mappings(hyp_idmap_start, size, hyp_idmap_start, + PAGE_HYP_EXEC); if (err) kvm_err("Failed to idmap %lx-%lx\n", hyp_idmap_start, hyp_idmap_end); @@ -2367,6 +1186,7 @@ static int kvm_map_idmap_text(pgd_t *pgd) int kvm_mmu_init(void) { int err; + u32 hyp_va_bits; hyp_idmap_start = __pa_symbol(__hyp_idmap_text_start); hyp_idmap_start = ALIGN_DOWN(hyp_idmap_start, PAGE_SIZE); @@ -2380,6 +1200,8 @@ int kvm_mmu_init(void) */ BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK); + hyp_va_bits = 64 - ((idmap_t0sz & TCR_T0SZ_MASK) >> TCR_T0SZ_OFFSET); + kvm_debug("Using %u-bit virtual addresses at EL2\n", hyp_va_bits); kvm_debug("IDMAP page: %lx\n", hyp_idmap_start); kvm_debug("HYP VA range: %lx:%lx\n", kern_hyp_va(PAGE_OFFSET), @@ -2397,43 +1219,30 @@ int kvm_mmu_init(void) goto out; } - hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order); - if (!hyp_pgd) { - kvm_err("Hyp mode PGD not allocated\n"); + hyp_pgtable = kzalloc(sizeof(*hyp_pgtable), GFP_KERNEL); + if (!hyp_pgtable) { + kvm_err("Hyp mode page-table not allocated\n"); err = -ENOMEM; goto out; } - if (__kvm_cpu_uses_extended_idmap()) { - boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, - hyp_pgd_order); - if (!boot_hyp_pgd) { - kvm_err("Hyp boot PGD not allocated\n"); - err = -ENOMEM; - goto out; - } - - err = kvm_map_idmap_text(boot_hyp_pgd); - if (err) - goto out; + err = kvm_pgtable_hyp_init(hyp_pgtable, hyp_va_bits); + if (err) + goto out_free_pgtable; - merged_hyp_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); - if (!merged_hyp_pgd) { - kvm_err("Failed to allocate extra HYP pgd\n"); - goto out; - } - __kvm_extend_hypmap(boot_hyp_pgd, hyp_pgd, merged_hyp_pgd, - hyp_idmap_start); - } else { - err = kvm_map_idmap_text(hyp_pgd); - if (err) - goto out; - } + err = kvm_map_idmap_text(); + if (err) + goto out_destroy_pgtable; io_map_base = hyp_idmap_start; return 0; + +out_destroy_pgtable: + kvm_pgtable_hyp_destroy(hyp_pgtable); +out_free_pgtable: + kfree(hyp_pgtable); + hyp_pgtable = NULL; out: - free_hyp_pgds(); return err; } @@ -2537,7 +1346,7 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm, spin_lock(&kvm->mmu_lock); if (ret) unmap_stage2_range(&kvm->arch.mmu, mem->guest_phys_addr, mem->memory_size); - else + else if (!cpus_have_final_cap(ARM64_HAS_STAGE2_FWB)) stage2_flush_memslot(kvm, memslot); spin_unlock(&kvm->mmu_lock); out: diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index f0d0312c0a55..ee13c5eecd3d 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -20,6 +20,21 @@ static void kvm_pmu_stop_counter(struct kvm_vcpu *vcpu, struct kvm_pmc *pmc); #define PERF_ATTR_CFG1_KVM_PMU_CHAINED 0x1 +static u32 kvm_pmu_event_mask(struct kvm *kvm) +{ + switch (kvm->arch.pmuver) { + case 1: /* ARMv8.0 */ + return GENMASK(9, 0); + case 4: /* ARMv8.1 */ + case 5: /* ARMv8.4 */ + case 6: /* ARMv8.5 */ + return GENMASK(15, 0); + default: /* Shouldn't be here, just for sanity */ + WARN_ONCE(1, "Unknown PMU version %d\n", kvm->arch.pmuver); + return 0; + } +} + /** * kvm_pmu_idx_is_64bit - determine if select_idx is a 64bit counter * @vcpu: The vcpu pointer @@ -100,7 +115,7 @@ static bool kvm_pmu_idx_has_chain_evtype(struct kvm_vcpu *vcpu, u64 select_idx) return false; reg = PMEVTYPER0_EL0 + select_idx; - eventsel = __vcpu_sys_reg(vcpu, reg) & ARMV8_PMU_EVTYPE_EVENT; + eventsel = __vcpu_sys_reg(vcpu, reg) & kvm_pmu_event_mask(vcpu->kvm); return eventsel == ARMV8_PMUV3_PERFCTR_CHAIN; } @@ -495,7 +510,7 @@ void kvm_pmu_software_increment(struct kvm_vcpu *vcpu, u64 val) /* PMSWINC only applies to ... SW_INC! */ type = __vcpu_sys_reg(vcpu, PMEVTYPER0_EL0 + i); - type &= ARMV8_PMU_EVTYPE_EVENT; + type &= kvm_pmu_event_mask(vcpu->kvm); if (type != ARMV8_PMUV3_PERFCTR_SW_INCR) continue; @@ -578,11 +593,21 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx) data = __vcpu_sys_reg(vcpu, reg); kvm_pmu_stop_counter(vcpu, pmc); - eventsel = data & ARMV8_PMU_EVTYPE_EVENT; + if (pmc->idx == ARMV8_PMU_CYCLE_IDX) + eventsel = ARMV8_PMUV3_PERFCTR_CPU_CYCLES; + else + eventsel = data & kvm_pmu_event_mask(vcpu->kvm); - /* Software increment event does't need to be backed by a perf event */ - if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR && - pmc->idx != ARMV8_PMU_CYCLE_IDX) + /* Software increment event doesn't need to be backed by a perf event */ + if (eventsel == ARMV8_PMUV3_PERFCTR_SW_INCR) + return; + + /* + * If we have a filter in place and that the event isn't allowed, do + * not install a perf event either. + */ + if (vcpu->kvm->arch.pmu_filter && + !test_bit(eventsel, vcpu->kvm->arch.pmu_filter)) return; memset(&attr, 0, sizeof(struct perf_event_attr)); @@ -594,8 +619,7 @@ static void kvm_pmu_create_perf_event(struct kvm_vcpu *vcpu, u64 select_idx) attr.exclude_kernel = data & ARMV8_PMU_EXCLUDE_EL1 ? 1 : 0; attr.exclude_hv = 1; /* Don't count EL2 events */ attr.exclude_host = 1; /* Don't count host events */ - attr.config = (pmc->idx == ARMV8_PMU_CYCLE_IDX) ? - ARMV8_PMUV3_PERFCTR_CPU_CYCLES : eventsel; + attr.config = eventsel; counter = kvm_pmu_get_pair_counter_value(vcpu, pmc); @@ -679,17 +703,95 @@ static void kvm_pmu_update_pmc_chained(struct kvm_vcpu *vcpu, u64 select_idx) void kvm_pmu_set_counter_event_type(struct kvm_vcpu *vcpu, u64 data, u64 select_idx) { - u64 reg, event_type = data & ARMV8_PMU_EVTYPE_MASK; + u64 reg, mask; + + mask = ARMV8_PMU_EVTYPE_MASK; + mask &= ~ARMV8_PMU_EVTYPE_EVENT; + mask |= kvm_pmu_event_mask(vcpu->kvm); reg = (select_idx == ARMV8_PMU_CYCLE_IDX) ? PMCCFILTR_EL0 : PMEVTYPER0_EL0 + select_idx; - __vcpu_sys_reg(vcpu, reg) = event_type; + __vcpu_sys_reg(vcpu, reg) = data & mask; kvm_pmu_update_pmc_chained(vcpu, select_idx); kvm_pmu_create_perf_event(vcpu, select_idx); } +static int kvm_pmu_probe_pmuver(void) +{ + struct perf_event_attr attr = { }; + struct perf_event *event; + struct arm_pmu *pmu; + int pmuver = 0xf; + + /* + * Create a dummy event that only counts user cycles. As we'll never + * leave this function with the event being live, it will never + * count anything. But it allows us to probe some of the PMU + * details. Yes, this is terrible. + */ + attr.type = PERF_TYPE_RAW; + attr.size = sizeof(attr); + attr.pinned = 1; + attr.disabled = 0; + attr.exclude_user = 0; + attr.exclude_kernel = 1; + attr.exclude_hv = 1; + attr.exclude_host = 1; + attr.config = ARMV8_PMUV3_PERFCTR_CPU_CYCLES; + attr.sample_period = GENMASK(63, 0); + + event = perf_event_create_kernel_counter(&attr, -1, current, + kvm_pmu_perf_overflow, &attr); + + if (IS_ERR(event)) { + pr_err_once("kvm: pmu event creation failed %ld\n", + PTR_ERR(event)); + return 0xf; + } + + if (event->pmu) { + pmu = to_arm_pmu(event->pmu); + if (pmu->pmuver) + pmuver = pmu->pmuver; + } + + perf_event_disable(event); + perf_event_release_kernel(event); + + return pmuver; +} + +u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) +{ + unsigned long *bmap = vcpu->kvm->arch.pmu_filter; + u64 val, mask = 0; + int base, i; + + if (!pmceid1) { + val = read_sysreg(pmceid0_el0); + base = 0; + } else { + val = read_sysreg(pmceid1_el0); + base = 32; + } + + if (!bmap) + return val; + + for (i = 0; i < 32; i += 8) { + u64 byte; + + byte = bitmap_get_value8(bmap, base + i); + mask |= byte << i; + byte = bitmap_get_value8(bmap, 0x4000 + base + i); + mask |= byte << (32 + i); + } + + return val & mask; +} + bool kvm_arm_support_pmu_v3(void) { /* @@ -735,15 +837,6 @@ int kvm_arm_pmu_v3_enable(struct kvm_vcpu *vcpu) static int kvm_arm_pmu_v3_init(struct kvm_vcpu *vcpu) { - if (!kvm_arm_support_pmu_v3()) - return -ENODEV; - - if (!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) - return -ENXIO; - - if (vcpu->arch.pmu.created) - return -EBUSY; - if (irqchip_in_kernel(vcpu->kvm)) { int ret; @@ -796,6 +889,19 @@ static bool pmu_irq_is_valid(struct kvm *kvm, int irq) int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) { + if (!kvm_arm_support_pmu_v3() || + !test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) + return -ENODEV; + + if (vcpu->arch.pmu.created) + return -EBUSY; + + if (!vcpu->kvm->arch.pmuver) + vcpu->kvm->arch.pmuver = kvm_pmu_probe_pmuver(); + + if (vcpu->kvm->arch.pmuver == 0xf) + return -ENODEV; + switch (attr->attr) { case KVM_ARM_VCPU_PMU_V3_IRQ: { int __user *uaddr = (int __user *)(long)attr->addr; @@ -804,9 +910,6 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) if (!irqchip_in_kernel(vcpu->kvm)) return -EINVAL; - if (!test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) - return -ENODEV; - if (get_user(irq, uaddr)) return -EFAULT; @@ -824,6 +927,53 @@ int kvm_arm_pmu_v3_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) vcpu->arch.pmu.irq_num = irq; return 0; } + case KVM_ARM_VCPU_PMU_V3_FILTER: { + struct kvm_pmu_event_filter __user *uaddr; + struct kvm_pmu_event_filter filter; + int nr_events; + + nr_events = kvm_pmu_event_mask(vcpu->kvm) + 1; + + uaddr = (struct kvm_pmu_event_filter __user *)(long)attr->addr; + + if (copy_from_user(&filter, uaddr, sizeof(filter))) + return -EFAULT; + + if (((u32)filter.base_event + filter.nevents) > nr_events || + (filter.action != KVM_PMU_EVENT_ALLOW && + filter.action != KVM_PMU_EVENT_DENY)) + return -EINVAL; + + mutex_lock(&vcpu->kvm->lock); + + if (!vcpu->kvm->arch.pmu_filter) { + vcpu->kvm->arch.pmu_filter = bitmap_alloc(nr_events, GFP_KERNEL); + if (!vcpu->kvm->arch.pmu_filter) { + mutex_unlock(&vcpu->kvm->lock); + return -ENOMEM; + } + + /* + * The default depends on the first applied filter. + * If it allows events, the default is to deny. + * Conversely, if the first filter denies a set of + * events, the default is to allow. + */ + if (filter.action == KVM_PMU_EVENT_ALLOW) + bitmap_zero(vcpu->kvm->arch.pmu_filter, nr_events); + else + bitmap_fill(vcpu->kvm->arch.pmu_filter, nr_events); + } + + if (filter.action == KVM_PMU_EVENT_ALLOW) + bitmap_set(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents); + else + bitmap_clear(vcpu->kvm->arch.pmu_filter, filter.base_event, filter.nevents); + + mutex_unlock(&vcpu->kvm->lock); + + return 0; + } case KVM_ARM_VCPU_PMU_V3_INIT: return kvm_arm_pmu_v3_init(vcpu); } @@ -860,6 +1010,7 @@ int kvm_arm_pmu_v3_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr) switch (attr->attr) { case KVM_ARM_VCPU_PMU_V3_IRQ: case KVM_ARM_VCPU_PMU_V3_INIT: + case KVM_ARM_VCPU_PMU_V3_FILTER: if (kvm_arm_support_pmu_v3() && test_bit(KVM_ARM_VCPU_PMU_V3, vcpu->arch.features)) return 0; diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c index 3c224162b3dd..faf32a44ba04 100644 --- a/arch/arm64/kvm/pmu.c +++ b/arch/arm64/kvm/pmu.c @@ -31,9 +31,9 @@ static bool kvm_pmu_switch_needed(struct perf_event_attr *attr) */ void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) { - struct kvm_host_data *ctx = this_cpu_ptr(&kvm_host_data); + struct kvm_host_data *ctx = this_cpu_ptr_hyp_sym(kvm_host_data); - if (!kvm_pmu_switch_needed(attr)) + if (!ctx || !kvm_pmu_switch_needed(attr)) return; if (!attr->exclude_host) @@ -47,7 +47,10 @@ void kvm_set_pmu_events(u32 set, struct perf_event_attr *attr) */ void kvm_clr_pmu_events(u32 clr) { - struct kvm_host_data *ctx = this_cpu_ptr(&kvm_host_data); + struct kvm_host_data *ctx = this_cpu_ptr_hyp_sym(kvm_host_data); + + if (!ctx) + return; ctx->pmu_events.events_host &= ~clr; ctx->pmu_events.events_guest &= ~clr; @@ -173,7 +176,7 @@ void kvm_vcpu_pmu_restore_guest(struct kvm_vcpu *vcpu) return; preempt_disable(); - host = this_cpu_ptr(&kvm_host_data); + host = this_cpu_ptr_hyp_sym(kvm_host_data); events_guest = host->pmu_events.events_guest; events_host = host->pmu_events.events_host; @@ -193,7 +196,7 @@ void kvm_vcpu_pmu_restore_host(struct kvm_vcpu *vcpu) if (!has_vhe()) return; - host = this_cpu_ptr(&kvm_host_data); + host = this_cpu_ptr_hyp_sym(kvm_host_data); events_guest = host->pmu_events.events_guest; events_host = host->pmu_events.events_host; diff --git a/arch/arm64/kvm/psci.c b/arch/arm64/kvm/psci.c index 83415e96b589..db4056ecccfd 100644 --- a/arch/arm64/kvm/psci.c +++ b/arch/arm64/kvm/psci.c @@ -425,27 +425,30 @@ static int get_kernel_wa_level(u64 regid) { switch (regid) { case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - switch (kvm_arm_harden_branch_predictor()) { - case KVM_BP_HARDEN_UNKNOWN: + switch (arm64_get_spectre_v2_state()) { + case SPECTRE_VULNERABLE: return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; - case KVM_BP_HARDEN_WA_NEEDED: + case SPECTRE_MITIGATED: return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_AVAIL; - case KVM_BP_HARDEN_NOT_REQUIRED: + case SPECTRE_UNAFFECTED: return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_REQUIRED; } return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1_NOT_AVAIL; case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: - switch (kvm_arm_have_ssbd()) { - case KVM_SSBD_FORCE_DISABLE: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; - case KVM_SSBD_KERNEL: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL; - case KVM_SSBD_FORCE_ENABLE: - case KVM_SSBD_MITIGATED: + switch (arm64_get_spectre_v4_state()) { + case SPECTRE_MITIGATED: + /* + * As for the hypercall discovery, we pretend we + * don't have any FW mitigation if SSBS is there at + * all times. + */ + if (cpus_have_final_cap(ARM64_SSBS)) + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; + fallthrough; + case SPECTRE_UNAFFECTED: return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED; - case KVM_SSBD_UNKNOWN: - default: - return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNKNOWN; + case SPECTRE_VULNERABLE: + return KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; } } @@ -462,14 +465,8 @@ int kvm_arm_get_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) val = kvm_psci_version(vcpu, vcpu->kvm); break; case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_1: - val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK; - break; case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2: val = get_kernel_wa_level(reg->id) & KVM_REG_FEATURE_LEVEL_MASK; - - if (val == KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL && - kvm_arm_get_vcpu_workaround_2_flag(vcpu)) - val |= KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED; break; default: return -ENOENT; @@ -527,34 +524,35 @@ int kvm_arm_set_fw_reg(struct kvm_vcpu *vcpu, const struct kvm_one_reg *reg) KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED)) return -EINVAL; - wa_level = val & KVM_REG_FEATURE_LEVEL_MASK; - - if (get_kernel_wa_level(reg->id) < wa_level) - return -EINVAL; - /* The enabled bit must not be set unless the level is AVAIL. */ - if (wa_level != KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL && - wa_level != val) + if ((val & KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED) && + (val & KVM_REG_FEATURE_LEVEL_MASK) != KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL) return -EINVAL; - /* Are we finished or do we need to check the enable bit ? */ - if (kvm_arm_have_ssbd() != KVM_SSBD_KERNEL) - return 0; - /* - * If this kernel supports the workaround to be switched on - * or off, make sure it matches the requested setting. + * Map all the possible incoming states to the only two we + * really want to deal with. */ - switch (wa_level) { - case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL: - kvm_arm_set_vcpu_workaround_2_flag(vcpu, - val & KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_ENABLED); + switch (val & KVM_REG_FEATURE_LEVEL_MASK) { + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL: + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_UNKNOWN: + wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_AVAIL; break; + case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_AVAIL: case KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED: - kvm_arm_set_vcpu_workaround_2_flag(vcpu, true); + wa_level = KVM_REG_ARM_SMCCC_ARCH_WORKAROUND_2_NOT_REQUIRED; break; + default: + return -EINVAL; } + /* + * We can deal with NOT_AVAIL on NOT_REQUIRED, but not the + * other way around. + */ + if (get_kernel_wa_level(reg->id) < wa_level) + return -EINVAL; + return 0; default: return -ENOENT; diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c index ee33875c5c2a..f32490229a4c 100644 --- a/arch/arm64/kvm/reset.c +++ b/arch/arm64/kvm/reset.c @@ -319,10 +319,6 @@ int kvm_reset_vcpu(struct kvm_vcpu *vcpu) vcpu->arch.reset_state.reset = false; } - /* Default workaround setup is enabled (if supported) */ - if (kvm_arm_have_ssbd() == KVM_SSBD_KERNEL) - vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG; - /* Reset timer */ ret = kvm_timer_vcpu_reset(vcpu); out: @@ -339,7 +335,7 @@ u32 get_kvm_ipa_limit(void) int kvm_set_ipa_limit(void) { - unsigned int ipa_max, pa_max, va_max, parange, tgran_2; + unsigned int parange, tgran_2; u64 mmfr0; mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1); @@ -376,39 +372,11 @@ int kvm_set_ipa_limit(void) break; } - pa_max = id_aa64mmfr0_parange_to_phys_shift(parange); - - /* Clamp the IPA limit to the PA size supported by the kernel */ - ipa_max = (pa_max > PHYS_MASK_SHIFT) ? PHYS_MASK_SHIFT : pa_max; - /* - * Since our stage2 table is dependent on the stage1 page table code, - * we must always honor the following condition: - * - * Number of levels in Stage1 >= Number of levels in Stage2. - * - * So clamp the ipa limit further down to limit the number of levels. - * Since we can concatenate upto 16 tables at entry level, we could - * go upto 4bits above the maximum VA addressable with the current - * number of levels. - */ - va_max = PGDIR_SHIFT + PAGE_SHIFT - 3; - va_max += 4; - - if (va_max < ipa_max) - ipa_max = va_max; - - /* - * If the final limit is lower than the real physical address - * limit of the CPUs, report the reason. - */ - if (ipa_max < pa_max) - pr_info("kvm: Limiting the IPA size due to kernel %s Address limit\n", - (va_max < pa_max) ? "Virtual" : "Physical"); - - WARN(ipa_max < KVM_PHYS_SHIFT, - "KVM IPA limit (%d bit) is smaller than default size\n", ipa_max); - kvm_ipa_limit = ipa_max; - kvm_info("IPA Size Limit: %dbits\n", kvm_ipa_limit); + kvm_ipa_limit = id_aa64mmfr0_parange_to_phys_shift(parange); + WARN(kvm_ipa_limit < KVM_PHYS_SHIFT, + "KVM IPA Size Limit (%d bits) is smaller than default size\n", + kvm_ipa_limit); + kvm_info("IPA Size Limit: %d bits\n", kvm_ipa_limit); return 0; } diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 077293b5115f..3c203cb8c103 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -769,10 +769,7 @@ static bool access_pmceid(struct kvm_vcpu *vcpu, struct sys_reg_params *p, if (pmu_access_el0_disabled(vcpu)) return false; - if (!(p->Op2 & 1)) - pmceid = read_sysreg(pmceid0_el0); - else - pmceid = read_sysreg(pmceid1_el0); + pmceid = kvm_pmu_get_pmceid(vcpu, (p->Op2 & 1)); p->regval = pmceid; @@ -1131,6 +1128,9 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, if (!vcpu_has_sve(vcpu)) val &= ~(0xfUL << ID_AA64PFR0_SVE_SHIFT); val &= ~(0xfUL << ID_AA64PFR0_AMU_SHIFT); + if (!(val & (0xfUL << ID_AA64PFR0_CSV2_SHIFT)) && + arm64_get_spectre_v2_state() == SPECTRE_UNAFFECTED) + val |= (1UL << ID_AA64PFR0_CSV2_SHIFT); } else if (id == SYS_ID_AA64ISAR1_EL1 && !vcpu_has_ptrauth(vcpu)) { val &= ~((0xfUL << ID_AA64ISAR1_APA_SHIFT) | (0xfUL << ID_AA64ISAR1_API_SHIFT) | diff --git a/arch/arm64/kvm/vgic/vgic-debug.c b/arch/arm64/kvm/vgic/vgic-debug.c index b13a9e3f99dd..f38c40a76251 100644 --- a/arch/arm64/kvm/vgic/vgic-debug.c +++ b/arch/arm64/kvm/vgic/vgic-debug.c @@ -260,34 +260,14 @@ static int vgic_debug_show(struct seq_file *s, void *v) return 0; } -static const struct seq_operations vgic_debug_seq_ops = { +static const struct seq_operations vgic_debug_sops = { .start = vgic_debug_start, .next = vgic_debug_next, .stop = vgic_debug_stop, .show = vgic_debug_show }; -static int debug_open(struct inode *inode, struct file *file) -{ - int ret; - ret = seq_open(file, &vgic_debug_seq_ops); - if (!ret) { - struct seq_file *seq; - /* seq_open will have modified file->private_data */ - seq = file->private_data; - seq->private = inode->i_private; - } - - return ret; -}; - -static const struct file_operations vgic_debug_fops = { - .owner = THIS_MODULE, - .open = debug_open, - .read = seq_read, - .llseek = seq_lseek, - .release = seq_release -}; +DEFINE_SEQ_ATTRIBUTE(vgic_debug); void vgic_debug_init(struct kvm *kvm) { diff --git a/arch/arm64/kvm/vgic/vgic-v3.c b/arch/arm64/kvm/vgic/vgic-v3.c index 76e2d85789ed..9cdf39a94a63 100644 --- a/arch/arm64/kvm/vgic/vgic-v3.c +++ b/arch/arm64/kvm/vgic/vgic-v3.c @@ -662,7 +662,7 @@ void vgic_v3_load(struct kvm_vcpu *vcpu) if (likely(cpu_if->vgic_sre)) kvm_call_hyp(__vgic_v3_write_vmcr, cpu_if->vgic_vmcr); - kvm_call_hyp(__vgic_v3_restore_aprs, kern_hyp_va(cpu_if)); + kvm_call_hyp(__vgic_v3_restore_aprs, cpu_if); if (has_vhe()) __vgic_v3_activate_traps(cpu_if); @@ -686,7 +686,7 @@ void vgic_v3_put(struct kvm_vcpu *vcpu) vgic_v3_vmcr_sync(vcpu); - kvm_call_hyp(__vgic_v3_save_aprs, kern_hyp_va(cpu_if)); + kvm_call_hyp(__vgic_v3_save_aprs, cpu_if); if (has_vhe()) __vgic_v3_deactivate_traps(cpu_if); |