diff options
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 18 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 64 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.h | 23 |
3 files changed, 103 insertions, 2 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index d2fa64bddb57..62bf93dc0825 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -2093,6 +2093,15 @@ int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) else msr_info->data = vmx->pt_desc.guest.addr_a[index / 2]; break; + case MSR_IA32_S_CET: + msr_info->data = vmcs_readl(GUEST_S_CET); + break; + case MSR_KVM_INTERNAL_GUEST_SSP: + msr_info->data = vmcs_readl(GUEST_SSP); + break; + case MSR_IA32_INT_SSP_TAB: + msr_info->data = vmcs_readl(GUEST_INTR_SSP_TABLE); + break; case MSR_IA32_DEBUGCTLMSR: msr_info->data = vmx_guest_debugctl_read(); break; @@ -2411,6 +2420,15 @@ int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) else vmx->pt_desc.guest.addr_a[index / 2] = data; break; + case MSR_IA32_S_CET: + vmcs_writel(GUEST_S_CET, data); + break; + case MSR_KVM_INTERNAL_GUEST_SSP: + vmcs_writel(GUEST_SSP, data); + break; + case MSR_IA32_INT_SSP_TAB: + vmcs_writel(GUEST_INTR_SSP_TABLE, data); + break; case MSR_IA32_PERF_CAPABILITIES: if (data & PERF_CAP_LBR_FMT) { if ((data & PERF_CAP_LBR_FMT) != diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d85bb723f25a..54d280fe9a4b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1890,6 +1890,44 @@ static int __kvm_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data, data = (u32)data; break; + case MSR_IA32_U_CET: + case MSR_IA32_S_CET: + if (!guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK) && + !guest_cpu_cap_has(vcpu, X86_FEATURE_IBT)) + return KVM_MSR_RET_UNSUPPORTED; + if (!kvm_is_valid_u_s_cet(vcpu, data)) + return 1; + break; + case MSR_KVM_INTERNAL_GUEST_SSP: + if (!host_initiated) + return 1; + fallthrough; + /* + * Note that the MSR emulation here is flawed when a vCPU + * doesn't support the Intel 64 architecture. The expected + * architectural behavior in this case is that the upper 32 + * bits do not exist and should always read '0'. However, + * because the actual hardware on which the virtual CPU is + * running does support Intel 64, XRSTORS/XSAVES in the + * guest could observe behavior that violates the + * architecture. Intercepting XRSTORS/XSAVES for this + * special case isn't deemed worthwhile. + */ + case MSR_IA32_PL0_SSP ... MSR_IA32_INT_SSP_TAB: + if (!guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK)) + return KVM_MSR_RET_UNSUPPORTED; + /* + * MSR_IA32_INT_SSP_TAB is not present on processors that do + * not support Intel 64 architecture. + */ + if (index == MSR_IA32_INT_SSP_TAB && !guest_cpu_cap_has(vcpu, X86_FEATURE_LM)) + return KVM_MSR_RET_UNSUPPORTED; + if (is_noncanonical_msr_address(data, vcpu)) + return 1; + /* All SSP MSRs except MSR_IA32_INT_SSP_TAB must be 4-byte aligned */ + if (index != MSR_IA32_INT_SSP_TAB && !IS_ALIGNED(data, 4)) + return 1; + break; } msr.data = data; @@ -1934,6 +1972,20 @@ static int __kvm_get_msr(struct kvm_vcpu *vcpu, u32 index, u64 *data, !guest_cpu_cap_has(vcpu, X86_FEATURE_RDPID)) return 1; break; + case MSR_IA32_U_CET: + case MSR_IA32_S_CET: + if (!guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK) && + !guest_cpu_cap_has(vcpu, X86_FEATURE_IBT)) + return KVM_MSR_RET_UNSUPPORTED; + break; + case MSR_KVM_INTERNAL_GUEST_SSP: + if (!host_initiated) + return 1; + fallthrough; + case MSR_IA32_PL0_SSP ... MSR_IA32_INT_SSP_TAB: + if (!guest_cpu_cap_has(vcpu, X86_FEATURE_SHSTK)) + return KVM_MSR_RET_UNSUPPORTED; + break; } msr.index = index; @@ -3865,12 +3917,12 @@ static __always_inline void kvm_access_xstate_msr(struct kvm_vcpu *vcpu, kvm_fpu_put(); } -static __maybe_unused void kvm_set_xstate_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) +static void kvm_set_xstate_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { kvm_access_xstate_msr(vcpu, msr_info, MSR_TYPE_W); } -static __maybe_unused void kvm_get_xstate_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) +static void kvm_get_xstate_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { kvm_access_xstate_msr(vcpu, msr_info, MSR_TYPE_R); } @@ -4256,6 +4308,10 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) vcpu->arch.guest_fpu.xfd_err = data; break; #endif + case MSR_IA32_U_CET: + case MSR_IA32_PL0_SSP ... MSR_IA32_PL3_SSP: + kvm_set_xstate_msr(vcpu, msr_info); + break; default: if (kvm_pmu_is_valid_msr(vcpu, msr)) return kvm_pmu_set_msr(vcpu, msr_info); @@ -4605,6 +4661,10 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) msr_info->data = vcpu->arch.guest_fpu.xfd_err; break; #endif + case MSR_IA32_U_CET: + case MSR_IA32_PL0_SSP ... MSR_IA32_PL3_SSP: + kvm_get_xstate_msr(vcpu, msr_info); + break; default: if (kvm_pmu_is_valid_msr(vcpu, msr_info->index)) return kvm_pmu_get_msr(vcpu, msr_info); diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index a7c9c72fca93..076eccba0f7e 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -710,4 +710,27 @@ int ____kvm_emulate_hypercall(struct kvm_vcpu *vcpu, int cpl, 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 |