diff options
Diffstat (limited to 'arch/x86/kvm/svm/sev.c')
-rw-r--r-- | arch/x86/kvm/svm/sev.c | 190 |
1 files changed, 151 insertions, 39 deletions
diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c index e5a4d9b0e79f..022d92fb4b85 100644 --- a/arch/x86/kvm/svm/sev.c +++ b/arch/x86/kvm/svm/sev.c @@ -23,6 +23,7 @@ #include <asm/pkru.h> #include <asm/trapnr.h> #include <asm/fpu/xcr.h> +#include <asm/fpu/xstate.h> #include <asm/debugreg.h> #include "mmu.h" @@ -32,22 +33,9 @@ #include "cpuid.h" #include "trace.h" -#ifndef CONFIG_KVM_AMD_SEV -/* - * When this config is not defined, SEV feature is not supported and APIs in - * this file are not used but this file still gets compiled into the KVM AMD - * module. - * - * We will not have MISC_CG_RES_SEV and MISC_CG_RES_SEV_ES entries in the enum - * misc_res_type {} defined in linux/misc_cgroup.h. - * - * Below macros allow compilation to succeed. - */ -#define MISC_CG_RES_SEV MISC_CG_RES_TYPES -#define MISC_CG_RES_SEV_ES MISC_CG_RES_TYPES -#endif +#define GHCB_VERSION_MAX 1ULL +#define GHCB_VERSION_MIN 1ULL -#ifdef CONFIG_KVM_AMD_SEV /* enable/disable SEV support */ static bool sev_enabled = true; module_param_named(sev, sev_enabled, bool, 0444); @@ -57,13 +45,9 @@ static bool sev_es_enabled = true; module_param_named(sev_es, sev_es_enabled, bool, 0444); /* enable/disable SEV-ES DebugSwap support */ -static bool sev_es_debug_swap_enabled = false; +static bool sev_es_debug_swap_enabled = true; module_param_named(debug_swap, sev_es_debug_swap_enabled, bool, 0444); -#else -#define sev_enabled false -#define sev_es_enabled false -#define sev_es_debug_swap_enabled false -#endif /* CONFIG_KVM_AMD_SEV */ +static u64 sev_supported_vmsa_features; static u8 sev_enc_bit; static DECLARE_RWSEM(sev_deactivate_lock); @@ -113,7 +97,15 @@ static int sev_flush_asids(unsigned int min_asid, unsigned int max_asid) static inline bool is_mirroring_enc_context(struct kvm *kvm) { - return !!to_kvm_svm(kvm)->sev_info.enc_context_owner; + return !!to_kvm_sev_info(kvm)->enc_context_owner; +} + +static bool sev_vcpu_has_debug_swap(struct vcpu_svm *svm) +{ + struct kvm_vcpu *vcpu = &svm->vcpu; + struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; + + return sev->vmsa_features & SVM_SEV_FEAT_DEBUG_SWAP; } /* Must be called with the sev_bitmap_lock held */ @@ -251,20 +243,32 @@ static void sev_unbind_asid(struct kvm *kvm, unsigned int handle) sev_decommission(handle); } -static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) +static int __sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp, + struct kvm_sev_init *data, + unsigned long vm_type) { struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; struct sev_platform_init_args init_args = {0}; + bool es_active = vm_type != KVM_X86_SEV_VM; + u64 valid_vmsa_features = es_active ? sev_supported_vmsa_features : 0; int ret; if (kvm->created_vcpus) return -EINVAL; + if (data->flags) + return -EINVAL; + + if (data->vmsa_features & ~valid_vmsa_features) + return -EINVAL; + if (unlikely(sev->active)) return -EINVAL; sev->active = true; - sev->es_active = argp->id == KVM_SEV_ES_INIT; + sev->es_active = es_active; + sev->vmsa_features = data->vmsa_features; + ret = sev_asid_new(sev); if (ret) goto e_no_asid; @@ -276,6 +280,7 @@ static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) INIT_LIST_HEAD(&sev->regions_list); INIT_LIST_HEAD(&sev->mirror_vms); + sev->need_init = false; kvm_set_apicv_inhibit(kvm, APICV_INHIBIT_REASON_SEV); @@ -286,11 +291,44 @@ e_free: sev_asid_free(sev); sev->asid = 0; e_no_asid: + sev->vmsa_features = 0; sev->es_active = false; sev->active = false; return ret; } +static int sev_guest_init(struct kvm *kvm, struct kvm_sev_cmd *argp) +{ + struct kvm_sev_init data = { + .vmsa_features = 0, + }; + unsigned long vm_type; + + if (kvm->arch.vm_type != KVM_X86_DEFAULT_VM) + return -EINVAL; + + vm_type = (argp->id == KVM_SEV_INIT ? KVM_X86_SEV_VM : KVM_X86_SEV_ES_VM); + return __sev_guest_init(kvm, argp, &data, vm_type); +} + +static int sev_guest_init2(struct kvm *kvm, struct kvm_sev_cmd *argp) +{ + struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info; + struct kvm_sev_init data; + + if (!sev->need_init) + return -EINVAL; + + if (kvm->arch.vm_type != KVM_X86_SEV_VM && + kvm->arch.vm_type != KVM_X86_SEV_ES_VM) + return -EINVAL; + + if (copy_from_user(&data, u64_to_user_ptr(argp->data), sizeof(data))) + return -EFAULT; + + return __sev_guest_init(kvm, argp, &data, kvm->arch.vm_type); +} + static int sev_bind_asid(struct kvm *kvm, unsigned int handle, int *error) { unsigned int asid = sev_get_asid(kvm); @@ -580,7 +618,13 @@ e_unpin: static int sev_es_sync_vmsa(struct vcpu_svm *svm) { + struct kvm_vcpu *vcpu = &svm->vcpu; + struct kvm_sev_info *sev = &to_kvm_svm(vcpu->kvm)->sev_info; struct sev_es_save_area *save = svm->sev_es.vmsa; + struct xregs_state *xsave; + const u8 *s; + u8 *d; + int i; /* Check some debug related fields before encrypting the VMSA */ if (svm->vcpu.guest_debug || (svm->vmcb->save.dr7 & ~DR7_FIXED_1)) @@ -621,10 +665,44 @@ static int sev_es_sync_vmsa(struct vcpu_svm *svm) save->xss = svm->vcpu.arch.ia32_xss; save->dr6 = svm->vcpu.arch.dr6; - if (sev_es_debug_swap_enabled) { - save->sev_features |= SVM_SEV_FEAT_DEBUG_SWAP; - pr_warn_once("Enabling DebugSwap with KVM_SEV_ES_INIT. " - "This will not work starting with Linux 6.10\n"); + save->sev_features = sev->vmsa_features; + + /* + * Skip FPU and AVX setup with KVM_SEV_ES_INIT to avoid + * breaking older measurements. + */ + if (vcpu->kvm->arch.vm_type != KVM_X86_DEFAULT_VM) { + xsave = &vcpu->arch.guest_fpu.fpstate->regs.xsave; + save->x87_dp = xsave->i387.rdp; + save->mxcsr = xsave->i387.mxcsr; + save->x87_ftw = xsave->i387.twd; + save->x87_fsw = xsave->i387.swd; + save->x87_fcw = xsave->i387.cwd; + save->x87_fop = xsave->i387.fop; + save->x87_ds = 0; + save->x87_cs = 0; + save->x87_rip = xsave->i387.rip; + + for (i = 0; i < 8; i++) { + /* + * The format of the x87 save area is undocumented and + * definitely not what you would expect. It consists of + * an 8*8 bytes area with bytes 0-7, and an 8*2 bytes + * area with bytes 8-9 of each register. + */ + d = save->fpreg_x87 + i * 8; + s = ((u8 *)xsave->i387.st_space) + i * 16; + memcpy(d, s, 8); + save->fpreg_x87[64 + i * 2] = s[8]; + save->fpreg_x87[64 + i * 2 + 1] = s[9]; + } + memcpy(save->fpreg_xmm, xsave->i387.xmm_space, 256); + + s = get_xsave_addr(xsave, XFEATURE_YMM); + if (s) + memcpy(save->fpreg_ymm, s, 256); + else + memset(save->fpreg_ymm, 0, 256); } pr_debug("Virtual Machine Save Area (VMSA):\n"); @@ -658,13 +736,20 @@ static int __sev_launch_update_vmsa(struct kvm *kvm, struct kvm_vcpu *vcpu, clflush_cache_range(svm->sev_es.vmsa, PAGE_SIZE); vmsa.reserved = 0; - vmsa.handle = to_kvm_svm(kvm)->sev_info.handle; + vmsa.handle = to_kvm_sev_info(kvm)->handle; vmsa.address = __sme_pa(svm->sev_es.vmsa); vmsa.len = PAGE_SIZE; ret = sev_issue_cmd(kvm, SEV_CMD_LAUNCH_UPDATE_VMSA, &vmsa, error); if (ret) return ret; + /* + * SEV-ES guests maintain an encrypted version of their FPU + * state which is restored and saved on VMRUN and VMEXIT. + * Mark vcpu->arch.guest_fpu->fpstate as scratch so it won't + * do xsave/xrstor on it. + */ + fpstate_set_confidential(&vcpu->arch.guest_fpu); vcpu->arch.guest_state_protected = true; return 0; } @@ -1705,6 +1790,7 @@ static void sev_migrate_from(struct kvm *dst_kvm, struct kvm *src_kvm) dst->pages_locked = src->pages_locked; dst->enc_context_owner = src->enc_context_owner; dst->es_active = src->es_active; + dst->vmsa_features = src->vmsa_features; src->asid = 0; src->active = false; @@ -1812,7 +1898,8 @@ int sev_vm_move_enc_context_from(struct kvm *kvm, unsigned int source_fd) if (ret) goto out_fput; - if (sev_guest(kvm) || !sev_guest(source_kvm)) { + if (kvm->arch.vm_type != source_kvm->arch.vm_type || + sev_guest(kvm) || !sev_guest(source_kvm)) { ret = -EINVAL; goto out_unlock; } @@ -1861,6 +1948,21 @@ out_fput: return ret; } +int sev_dev_get_attr(u32 group, u64 attr, u64 *val) +{ + if (group != KVM_X86_GRP_SEV) + return -ENXIO; + + switch (attr) { + case KVM_X86_SEV_VMSA_FEATURES: + *val = sev_supported_vmsa_features; + return 0; + + default: + return -ENXIO; + } +} + int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) { struct kvm_sev_cmd sev_cmd; @@ -1894,6 +1996,9 @@ int sev_mem_enc_ioctl(struct kvm *kvm, void __user *argp) case KVM_SEV_INIT: r = sev_guest_init(kvm, &sev_cmd); break; + case KVM_SEV_INIT2: + r = sev_guest_init2(kvm, &sev_cmd); + break; case KVM_SEV_LAUNCH_START: r = sev_launch_start(kvm, &sev_cmd); break; @@ -2121,6 +2226,7 @@ int sev_vm_copy_enc_context_from(struct kvm *kvm, unsigned int source_fd) mirror_sev->asid = source_sev->asid; mirror_sev->fd = source_sev->fd; mirror_sev->es_active = source_sev->es_active; + mirror_sev->need_init = false; mirror_sev->handle = source_sev->handle; INIT_LIST_HEAD(&mirror_sev->regions_list); INIT_LIST_HEAD(&mirror_sev->mirror_vms); @@ -2186,15 +2292,18 @@ void sev_vm_destroy(struct kvm *kvm) void __init sev_set_cpu_caps(void) { - if (!sev_enabled) - kvm_cpu_cap_clear(X86_FEATURE_SEV); - if (!sev_es_enabled) - kvm_cpu_cap_clear(X86_FEATURE_SEV_ES); + if (sev_enabled) { + kvm_cpu_cap_set(X86_FEATURE_SEV); + kvm_caps.supported_vm_types |= BIT(KVM_X86_SEV_VM); + } + if (sev_es_enabled) { + kvm_cpu_cap_set(X86_FEATURE_SEV_ES); + kvm_caps.supported_vm_types |= BIT(KVM_X86_SEV_ES_VM); + } } void __init sev_hardware_setup(void) { -#ifdef CONFIG_KVM_AMD_SEV unsigned int eax, ebx, ecx, edx, sev_asid_count, sev_es_asid_count; bool sev_es_supported = false; bool sev_supported = false; @@ -2294,7 +2403,10 @@ out: if (!sev_es_enabled || !cpu_feature_enabled(X86_FEATURE_DEBUG_SWAP) || !cpu_feature_enabled(X86_FEATURE_NO_NESTED_DATA_BP)) sev_es_debug_swap_enabled = false; -#endif + + sev_supported_vmsa_features = 0; + if (sev_es_debug_swap_enabled) + sev_supported_vmsa_features |= SVM_SEV_FEAT_DEBUG_SWAP; } void sev_hardware_unsetup(void) @@ -3063,7 +3175,7 @@ static void sev_es_init_vmcb(struct vcpu_svm *svm) svm_set_intercept(svm, TRAP_CR8_WRITE); vmcb->control.intercepts[INTERCEPT_DR] = 0; - if (!sev_es_debug_swap_enabled) { + if (!sev_vcpu_has_debug_swap(svm)) { vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_READ); vmcb_set_intercept(&vmcb->control, INTERCEPT_DR7_WRITE); recalc_intercepts(svm); @@ -3118,7 +3230,7 @@ void sev_es_vcpu_reset(struct vcpu_svm *svm) sev_enc_bit)); } -void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa) +void sev_es_prepare_switch_to_guest(struct vcpu_svm *svm, struct sev_es_save_area *hostsa) { /* * All host state for SEV-ES guests is categorized into three swap types @@ -3146,7 +3258,7 @@ void sev_es_prepare_switch_to_guest(struct sev_es_save_area *hostsa) * the CPU (Type-B). If DebugSwap is disabled/unsupported, the CPU both * saves and loads debug registers (Type-A). */ - if (sev_es_debug_swap_enabled) { + if (sev_vcpu_has_debug_swap(svm)) { hostsa->dr0 = native_get_debugreg(0); hostsa->dr1 = native_get_debugreg(1); hostsa->dr2 = native_get_debugreg(2); |