Expose PEBS feature to guest by IA32_MISC_ENABLE[bit12]. IA32_MISC_ENABLE[bit12] is Processor Event Based Sampling (PEBS) Unavailable (RO) flag: 1 = PEBS is not supported; 0 = PEBS is supported.
Signed-off-by: Luwei Kang <[email protected]> --- arch/x86/include/asm/kvm_host.h | 1 + arch/x86/kvm/svm.c | 6 ++++++ arch/x86/kvm/vmx/vmx.c | 1 + arch/x86/kvm/x86.c | 22 +++++++++++++++++----- 4 files changed, 25 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index 94af338..f6a5630 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -1130,6 +1130,7 @@ struct kvm_x86_ops { bool (*xsaves_supported)(void); bool (*umip_emulated)(void); bool (*pt_supported)(void); + bool (*pebs_supported)(void); bool (*pdcm_supported)(void); int (*check_nested_events)(struct kvm_vcpu *vcpu, bool external_intr); diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 8ae6716..2b271fc 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -6005,6 +6005,11 @@ static bool svm_pt_supported(void) return false; } +static bool svm_pebs_supported(void) +{ + return false; +} + static bool svm_pdcm_supported(void) { return false; @@ -7298,6 +7303,7 @@ static bool svm_need_emulation_on_page_fault(struct kvm_vcpu *vcpu) .xsaves_supported = svm_xsaves_supported, .umip_emulated = svm_umip_emulated, .pt_supported = svm_pt_supported, + .pebs_supported = svm_pebs_supported, .pdcm_supported = svm_pdcm_supported, .set_supported_cpuid = svm_set_supported_cpuid, diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index 71e3d42..d85f19b 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -7782,6 +7782,7 @@ static __exit void hardware_unsetup(void) .xsaves_supported = vmx_xsaves_supported, .umip_emulated = vmx_umip_emulated, .pt_supported = vmx_pt_supported, + .pebs_supported = vmx_pebs_supported, .pdcm_supported = vmx_pdcm_supported, .request_immediate_exit = vmx_request_immediate_exit, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 290c3c3..8ad501d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2483,6 +2483,7 @@ static void record_steal_time(struct kvm_vcpu *vcpu) int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) { bool pr = false; + bool update_cpuid = false; u32 msr = msr_info->index; u64 data = msr_info->data; @@ -2563,11 +2564,17 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) ((vcpu->arch.ia32_misc_enable_msr ^ data) & MSR_IA32_MISC_ENABLE_MWAIT)) { if (!guest_cpuid_has(vcpu, X86_FEATURE_XMM3)) return 1; - vcpu->arch.ia32_misc_enable_msr = data; - kvm_update_cpuid(vcpu); - } else { - vcpu->arch.ia32_misc_enable_msr = data; + update_cpuid = true; } + + if (kvm_x86_ops->pebs_supported()) + data &= ~MSR_IA32_MISC_ENABLE_PEBS; + else + data |= MSR_IA32_MISC_ENABLE_PEBS; + + vcpu->arch.ia32_misc_enable_msr = data; + if (update_cpuid) + kvm_update_cpuid(vcpu); break; case MSR_IA32_SMBASE: if (!msr_info->host_initiated) @@ -2875,7 +2882,12 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) msr_info->data = (u64)vcpu->arch.ia32_tsc_adjust_msr; break; case MSR_IA32_MISC_ENABLE: - msr_info->data = vcpu->arch.ia32_misc_enable_msr; + if (kvm_x86_ops->pebs_supported()) + msr_info->data = (vcpu->arch.ia32_misc_enable_msr & + ~MSR_IA32_MISC_ENABLE_PEBS); + else + msr_info->data = (vcpu->arch.ia32_misc_enable_msr | + MSR_IA32_MISC_ENABLE_PEBS); break; case MSR_IA32_SMBASE: if (!msr_info->host_initiated) -- 1.8.3.1
