diff options
Diffstat (limited to 'arch/x86/kvm/x86.h')
| -rw-r--r-- | arch/x86/kvm/x86.h | 259 |
1 files changed, 234 insertions, 25 deletions
diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index d80a4c6b5a38..fdab0ad49098 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -8,6 +8,9 @@ #include <asm/pvclock.h> #include "kvm_cache_regs.h" #include "kvm_emulate.h" +#include "cpuid.h" + +#define KVM_MAX_MCE_BANKS 32 struct kvm_caps { /* control of guest tsc rate supported? */ @@ -31,10 +34,50 @@ struct kvm_caps { u64 supported_xcr0; u64 supported_xss; u64 supported_perf_cap; + + u64 supported_quirks; + u64 inapplicable_quirks; +}; + +struct kvm_host_values { + /* + * The host's raw MAXPHYADDR, i.e. the number of non-reserved physical + * address bits irrespective of features that repurpose legal bits, + * e.g. MKTME. + */ + u8 maxphyaddr; + + u64 efer; + u64 xcr0; + u64 xss; + u64 s_cet; + u64 arch_capabilities; }; void kvm_spurious_fault(void); +#define SIZE_OF_MEMSLOTS_HASHTABLE \ + (sizeof(((struct kvm_memslots *)0)->id_hash) * 2 * KVM_MAX_NR_ADDRESS_SPACES) + +/* Sanity check the size of the memslot hash tables. */ +static_assert(SIZE_OF_MEMSLOTS_HASHTABLE == + (1024 * (1 + IS_ENABLED(CONFIG_X86_64)) * (1 + IS_ENABLED(CONFIG_KVM_SMM)))); + +/* + * Assert that "struct kvm_{svm,vmx,tdx}" is an order-0 or order-1 allocation. + * Spilling over to an order-2 allocation isn't fundamentally problematic, but + * isn't expected to happen in the foreseeable future (O(years)). Assert that + * the size is an order-0 allocation when ignoring the memslot hash tables, to + * help detect and debug unexpected size increases. + */ +#define KVM_SANITY_CHECK_VM_STRUCT_SIZE(x) \ +do { \ + BUILD_BUG_ON(get_order(sizeof(struct x) - SIZE_OF_MEMSLOTS_HASHTABLE) && \ + !IS_ENABLED(CONFIG_DEBUG_KERNEL) && !IS_ENABLED(CONFIG_KASAN)); \ + BUILD_BUG_ON(get_order(sizeof(struct x)) > 1 && \ + !IS_ENABLED(CONFIG_DEBUG_KERNEL) && !IS_ENABLED(CONFIG_KASAN)); \ +} while (0) + #define KVM_NESTED_VMENTER_CONSISTENCY_CHECK(consistency_check) \ ({ \ bool failed = (consistency_check); \ @@ -59,6 +102,16 @@ void kvm_spurious_fault(void); #define KVM_SVM_DEFAULT_PLE_WINDOW_MAX USHRT_MAX #define KVM_SVM_DEFAULT_PLE_WINDOW 3000 +/* + * KVM's internal, non-ABI indices for synthetic MSRs. The values themselves + * are arbitrary and have no meaning, the only requirement is that they don't + * conflict with "real" MSRs that KVM supports. Use values at the upper end + * of KVM's reserved paravirtual MSR range to minimize churn, i.e. these values + * will be usable until KVM exhausts its supply of paravirtual MSR indices. + */ + +#define MSR_KVM_INTERNAL_GUEST_SSP 0x4b564dff + static inline unsigned int __grow_ple_window(unsigned int val, unsigned int base, unsigned int modifier, unsigned int max) { @@ -89,16 +142,48 @@ static inline unsigned int __shrink_ple_window(unsigned int val, return max(val, min); } -#define MSR_IA32_CR_PAT_DEFAULT 0x0007040600070406ULL +#define MSR_IA32_CR_PAT_DEFAULT \ + PAT_VALUE(WB, WT, UC_MINUS, UC, WB, WT, UC_MINUS, UC) void kvm_service_local_tlb_flush_requests(struct kvm_vcpu *vcpu); int kvm_check_nested_events(struct kvm_vcpu *vcpu); +/* Forcibly leave the nested mode in cases like a vCPU reset */ +static inline void kvm_leave_nested(struct kvm_vcpu *vcpu) +{ + kvm_x86_ops.nested_ops->leave_nested(vcpu); +} + +/* + * If IBRS is advertised to the vCPU, KVM must flush the indirect branch + * predictors when transitioning from L2 to L1, as L1 expects hardware (KVM in + * this case) to provide separate predictor modes. Bare metal isolates the host + * from the guest, but doesn't isolate different guests from one another (in + * this case L1 and L2). The exception is if bare metal supports same mode IBRS, + * which offers protection within the same mode, and hence protects L1 from L2. + */ +static inline void kvm_nested_vmexit_handle_ibrs(struct kvm_vcpu *vcpu) +{ + if (cpu_feature_enabled(X86_FEATURE_AMD_IBRS_SAME_MODE)) + return; + + if (guest_cpu_cap_has(vcpu, X86_FEATURE_SPEC_CTRL) || + guest_cpu_cap_has(vcpu, X86_FEATURE_AMD_IBRS)) + indirect_branch_prediction_barrier(); +} + static inline bool kvm_vcpu_has_run(struct kvm_vcpu *vcpu) { return vcpu->arch.last_vmentry_cpu != -1; } +static inline void kvm_set_mp_state(struct kvm_vcpu *vcpu, int mp_state) +{ + vcpu->arch.mp_state = mp_state; + if (mp_state == KVM_MP_STATE_RUNNABLE) + vcpu->arch.pv.pv_unhalted = false; +} + static inline bool kvm_is_exception_pending(struct kvm_vcpu *vcpu) { return vcpu->arch.exception.pending || @@ -159,7 +244,7 @@ static inline bool is_64_bit_mode(struct kvm_vcpu *vcpu) if (!is_long_mode(vcpu)) return false; - static_call(kvm_x86_get_cs_db_l_bits)(vcpu, &cs_db, &cs_l); + kvm_x86_call(get_cs_db_l_bits)(vcpu, &cs_db, &cs_l); return cs_l; } @@ -212,9 +297,52 @@ static inline u8 vcpu_virt_addr_bits(struct kvm_vcpu *vcpu) return kvm_is_cr4_bit_set(vcpu, X86_CR4_LA57) ? 57 : 48; } -static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu) +static inline u8 max_host_virt_addr_bits(void) +{ + return kvm_cpu_cap_has(X86_FEATURE_LA57) ? 57 : 48; +} + +/* + * x86 MSRs which contain linear addresses, x86 hidden segment bases, and + * IDT/GDT bases have static canonicality checks, the size of which depends + * only on the CPU's support for 5-level paging, rather than on the state of + * CR4.LA57. This applies to both WRMSR and to other instructions that set + * their values, e.g. SGDT. + * + * KVM passes through most of these MSRS and also doesn't intercept the + * instructions that set the hidden segment bases. + * + * Because of this, to be consistent with hardware, even if the guest doesn't + * have LA57 enabled in its CPUID, perform canonicality checks based on *host* + * support for 5 level paging. + * + * Finally, instructions which are related to MMU invalidation of a given + * linear address, also have a similar static canonical check on address. + * This allows for example to invalidate 5-level addresses of a guest from a + * host which uses 4-level paging. + */ +static inline bool is_noncanonical_address(u64 la, struct kvm_vcpu *vcpu, + unsigned int flags) +{ + if (flags & (X86EMUL_F_INVLPG | X86EMUL_F_MSR | X86EMUL_F_DT_LOAD)) + return !__is_canonical_address(la, max_host_virt_addr_bits()); + else + return !__is_canonical_address(la, vcpu_virt_addr_bits(vcpu)); +} + +static inline bool is_noncanonical_msr_address(u64 la, struct kvm_vcpu *vcpu) +{ + return is_noncanonical_address(la, vcpu, X86EMUL_F_MSR); +} + +static inline bool is_noncanonical_base_address(u64 la, struct kvm_vcpu *vcpu) +{ + return is_noncanonical_address(la, vcpu, X86EMUL_F_DT_LOAD); +} + +static inline bool is_noncanonical_invlpg_address(u64 la, struct kvm_vcpu *vcpu) { - return !__is_canonical_address(la, vcpu_virt_addr_bits(vcpu)); + return is_noncanonical_address(la, vcpu, X86EMUL_F_INVLPG); } static inline void vcpu_cache_mmio_info(struct kvm_vcpu *vcpu, @@ -292,11 +420,26 @@ static inline bool kvm_check_has_quirk(struct kvm *kvm, u64 quirk) return !(kvm->arch.disabled_quirks & quirk); } +static __always_inline void kvm_request_l1tf_flush_l1d(void) +{ +#if IS_ENABLED(CONFIG_CPU_MITIGATIONS) && IS_ENABLED(CONFIG_KVM_INTEL) + /* + * Use a raw write to set the per-CPU flag, as KVM will ensure a flush + * even if preemption is currently enabled.. If the current vCPU task + * is migrated to a different CPU (or userspace runs the vCPU on a + * different task) before the next VM-Entry, then kvm_arch_vcpu_load() + * will request a flush on the new CPU. + */ + raw_cpu_write(irq_stat.kvm_cpu_l1tf_flush_l1d, 1); +#endif +} + void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip); u64 get_kvmclock_ns(struct kvm *kvm); uint64_t kvm_get_wall_clock_epoch(struct kvm *kvm); bool kvm_get_monotonic_and_clockread(s64 *kernel_ns, u64 *tsc_timestamp); +int kvm_guest_time_update(struct kvm_vcpu *v); int kvm_read_guest_virt(struct kvm_vcpu *vcpu, gva_t addr, void *val, unsigned int bytes, @@ -311,25 +454,20 @@ int handle_ud(struct kvm_vcpu *vcpu); void kvm_deliver_exception_payload(struct kvm_vcpu *vcpu, struct kvm_queued_exception *ex); -void kvm_vcpu_mtrr_init(struct kvm_vcpu *vcpu); -u8 kvm_mtrr_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn); int kvm_mtrr_set_msr(struct kvm_vcpu *vcpu, u32 msr, u64 data); int kvm_mtrr_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *pdata); -bool kvm_mtrr_check_gfn_range_consistency(struct kvm_vcpu *vcpu, gfn_t gfn, - int page_num); -bool kvm_vector_hashing_enabled(void); void kvm_fixup_and_inject_pf_error(struct kvm_vcpu *vcpu, gva_t gva, u16 error_code); int x86_decode_emulated_instruction(struct kvm_vcpu *vcpu, int emulation_type, void *insn, int insn_len); int x86_emulate_instruction(struct kvm_vcpu *vcpu, gpa_t cr2_or_gpa, int emulation_type, void *insn, int insn_len); -fastpath_t handle_fastpath_set_msr_irqoff(struct kvm_vcpu *vcpu); - -extern u64 host_xcr0; -extern u64 host_xss; -extern u64 host_arch_capabilities; +fastpath_t handle_fastpath_wrmsr(struct kvm_vcpu *vcpu); +fastpath_t handle_fastpath_wrmsr_imm(struct kvm_vcpu *vcpu, u32 msr, int reg); +fastpath_t handle_fastpath_hlt(struct kvm_vcpu *vcpu); +fastpath_t handle_fastpath_invd(struct kvm_vcpu *vcpu); extern struct kvm_caps kvm_caps; +extern struct kvm_host_values kvm_host; extern bool enable_pmu; @@ -409,24 +547,34 @@ static inline u64 nsec_to_cycles(struct kvm_vcpu *vcpu, u64 nsec) __rem; \ }) +static inline void kvm_disable_exits(struct kvm *kvm, u64 mask) +{ + kvm->arch.disabled_exits |= mask; +} + static inline bool kvm_mwait_in_guest(struct kvm *kvm) { - return kvm->arch.mwait_in_guest; + return kvm->arch.disabled_exits & KVM_X86_DISABLE_EXITS_MWAIT; } static inline bool kvm_hlt_in_guest(struct kvm *kvm) { - return kvm->arch.hlt_in_guest; + return kvm->arch.disabled_exits & KVM_X86_DISABLE_EXITS_HLT; } static inline bool kvm_pause_in_guest(struct kvm *kvm) { - return kvm->arch.pause_in_guest; + return kvm->arch.disabled_exits & KVM_X86_DISABLE_EXITS_PAUSE; } static inline bool kvm_cstate_in_guest(struct kvm *kvm) { - return kvm->arch.cstate_in_guest; + return kvm->arch.disabled_exits & KVM_X86_DISABLE_EXITS_CSTATE; +} + +static inline bool kvm_aperfmperf_in_guest(struct kvm *kvm) +{ + return kvm->arch.disabled_exits & KVM_X86_DISABLE_EXITS_APERFMPERF; } static inline bool kvm_notify_vmexit_enabled(struct kvm *kvm) @@ -488,22 +636,37 @@ static inline void kvm_machine_check(void) #endif } -void kvm_load_guest_xsave_state(struct kvm_vcpu *vcpu); -void kvm_load_host_xsave_state(struct kvm_vcpu *vcpu); int kvm_spec_ctrl_test_value(u64 value); -bool __kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4); int kvm_handle_memory_failure(struct kvm_vcpu *vcpu, int r, struct x86_exception *e); int kvm_handle_invpcid(struct kvm_vcpu *vcpu, unsigned long type, gva_t gva); bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type); +enum kvm_msr_access { + MSR_TYPE_R = BIT(0), + MSR_TYPE_W = BIT(1), + MSR_TYPE_RW = MSR_TYPE_R | MSR_TYPE_W, +}; + /* * Internal error codes that are used to indicate that MSR emulation encountered - * an error that should result in #GP in the guest, unless userspace - * handles it. + * an error that should result in #GP in the guest, unless userspace handles it. + * Note, '1', '0', and negative numbers are off limits, as they are used by KVM + * as part of KVM's lightly documented internal KVM_RUN return codes. + * + * UNSUPPORTED - The MSR isn't supported, either because it is completely + * unknown to KVM, or because the MSR should not exist according + * to the vCPU model. + * + * FILTERED - Access to the MSR is denied by a userspace MSR filter. */ -#define KVM_MSR_RET_INVALID 2 /* in-kernel MSR emulation #GP condition */ -#define KVM_MSR_RET_FILTERED 3 /* #GP due to userspace MSR filter */ +#define KVM_MSR_RET_UNSUPPORTED 2 +#define KVM_MSR_RET_FILTERED 3 + +static inline bool __kvm_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) +{ + return !(cr4 & vcpu->arch.cr4_guest_rsvd_bits); +} #define __cr4_reserved_bits(__cpu_has, __c) \ ({ \ @@ -529,6 +692,9 @@ bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type); __reserved_bits |= X86_CR4_PCIDE; \ if (!__cpu_has(__c, X86_FEATURE_LAM)) \ __reserved_bits |= X86_CR4_LAM_SUP; \ + if (!__cpu_has(__c, X86_FEATURE_SHSTK) && \ + !__cpu_has(__c, X86_FEATURE_IBT)) \ + __reserved_bits |= X86_CR4_CET; \ __reserved_bits; \ }) @@ -540,4 +706,47 @@ int kvm_sev_es_string_io(struct kvm_vcpu *vcpu, unsigned int size, unsigned int port, void *data, unsigned int count, int in); +static inline bool user_exit_on_hypercall(struct kvm *kvm, unsigned long hc_nr) +{ + return kvm->arch.hypercall_exit_enabled & BIT(hc_nr); +} + +int ____kvm_emulate_hypercall(struct kvm_vcpu *vcpu, int cpl, + int (*complete_hypercall)(struct kvm_vcpu *)); + +#define __kvm_emulate_hypercall(_vcpu, cpl, complete_hypercall) \ +({ \ + int __ret; \ + __ret = ____kvm_emulate_hypercall(_vcpu, cpl, complete_hypercall); \ + \ + if (__ret > 0) \ + __ret = complete_hypercall(_vcpu); \ + __ret; \ +}) + +int kvm_emulate_hypercall(struct kvm_vcpu *vcpu); + +#define CET_US_RESERVED_BITS GENMASK(9, 6) +#define CET_US_SHSTK_MASK_BITS GENMASK(1, 0) +#define CET_US_IBT_MASK_BITS (GENMASK_ULL(5, 2) | GENMASK_ULL(63, 10)) +#define CET_US_LEGACY_BITMAP_BASE(data) ((data) >> 12) + +static inline bool kvm_is_valid_u_s_cet(struct kvm_vcpu *vcpu, u64 data) +{ + if (data & CET_US_RESERVED_BITS) + return false; + if (!guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK) && + (data & CET_US_SHSTK_MASK_BITS)) + return false; + if (!guest_cpu_cap_has(vcpu, X86_FEATURE_IBT) && + (data & CET_US_IBT_MASK_BITS)) + return false; + if (!IS_ALIGNED(CET_US_LEGACY_BITMAP_BASE(data), 4)) + return false; + /* IBT can be suppressed iff the TRACKER isn't WAIT_ENDBR. */ + if ((data & CET_SUPPRESS) && (data & CET_WAIT_ENDBR)) + return false; + + return true; +} #endif |
