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| author | Kyle Huey <me@kylehuey.com> | 2017-03-20 01:16:28 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2017-04-21 12:50:06 +0200 |
| commit | db2336a80489e7c3c7728cefd9be58fac5ecfb39 (patch) | |
| tree | 2a462ecee35d68dea1b931ba5ee226933e663cd0 /arch/x86/kvm/x86.c | |
| parent | bd17117bb2af60d4bc44e0f9c859e800a3d99722 (diff) | |
| download | linux-db2336a80489e7c3c7728cefd9be58fac5ecfb39.tar.bz2 | |
KVM: x86: virtualize cpuid faulting
Hardware support for faulting on the cpuid instruction is not required to
emulate it, because cpuid triggers a VM exit anyways. KVM handles the relevant
MSRs (MSR_PLATFORM_INFO and MSR_MISC_FEATURES_ENABLE) and upon a
cpuid-induced VM exit checks the cpuid faulting state and the CPL.
kvm_require_cpl is even kind enough to inject the GP fault for us.
Signed-off-by: Kyle Huey <khuey@kylehuey.com>
Reviewed-by: David Matlack <dmatlack@google.com>
[Return "1" from kvm_emulate_cpuid, it's not void. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 34bf64fb4dea..49a69c0a0d50 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -1007,6 +1007,8 @@ static u32 emulated_msrs[] = { MSR_IA32_MCG_CTL, MSR_IA32_MCG_EXT_CTL, MSR_IA32_SMBASE, + MSR_PLATFORM_INFO, + MSR_MISC_FEATURES_ENABLES, }; static unsigned num_emulated_msrs; @@ -2314,6 +2316,21 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) return 1; vcpu->arch.osvw.status = data; break; + case MSR_PLATFORM_INFO: + if (!msr_info->host_initiated || + data & ~MSR_PLATFORM_INFO_CPUID_FAULT || + (!(data & MSR_PLATFORM_INFO_CPUID_FAULT) && + cpuid_fault_enabled(vcpu))) + return 1; + vcpu->arch.msr_platform_info = data; + break; + case MSR_MISC_FEATURES_ENABLES: + if (data & ~MSR_MISC_FEATURES_ENABLES_CPUID_FAULT || + (data & MSR_MISC_FEATURES_ENABLES_CPUID_FAULT && + !supports_cpuid_fault(vcpu))) + return 1; + vcpu->arch.msr_misc_features_enables = data; + break; default: if (msr && (msr == vcpu->kvm->arch.xen_hvm_config.msr)) return xen_hvm_config(vcpu, data); @@ -2529,6 +2546,12 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) return 1; msr_info->data = vcpu->arch.osvw.status; break; + case MSR_PLATFORM_INFO: + msr_info->data = vcpu->arch.msr_platform_info; + break; + case MSR_MISC_FEATURES_ENABLES: + msr_info->data = vcpu->arch.msr_misc_features_enables; + break; default: if (kvm_pmu_is_valid_msr(vcpu, msr_info->index)) return kvm_pmu_get_msr(vcpu, msr_info->index, &msr_info->data); @@ -7710,6 +7733,9 @@ void kvm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event) if (!init_event) { kvm_pmu_reset(vcpu); vcpu->arch.smbase = 0x30000; + + vcpu->arch.msr_platform_info = MSR_PLATFORM_INFO_CPUID_FAULT; + vcpu->arch.msr_misc_features_enables = 0; } memset(vcpu->arch.regs, 0, sizeof(vcpu->arch.regs)); |