diff options
Diffstat (limited to 'arch/x86/kvm/vmx/pmu_intel.c')
-rw-r--r-- | arch/x86/kvm/vmx/pmu_intel.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c index 254d9fc09863..7928d6dee0a2 100644 --- a/arch/x86/kvm/vmx/pmu_intel.c +++ b/arch/x86/kvm/vmx/pmu_intel.c @@ -586,6 +586,35 @@ static void intel_pmu_reset(struct kvm_vcpu *vcpu) intel_pmu_release_guest_lbr_event(vcpu); } +/* + * Emulate LBR_On_PMI behavior for 1 < pmu.version < 4. + * + * If Freeze_LBR_On_PMI = 1, the LBR is frozen on PMI and + * the KVM emulates to clear the LBR bit (bit 0) in IA32_DEBUGCTL. + * + * Guest needs to re-enable LBR to resume branches recording. + */ +static void intel_pmu_legacy_freezing_lbrs_on_pmi(struct kvm_vcpu *vcpu) +{ + u64 data = vmcs_read64(GUEST_IA32_DEBUGCTL); + + if (data & DEBUGCTLMSR_FREEZE_LBRS_ON_PMI) { + data &= ~DEBUGCTLMSR_LBR; + vmcs_write64(GUEST_IA32_DEBUGCTL, data); + } +} + +static void intel_pmu_deliver_pmi(struct kvm_vcpu *vcpu) +{ + u8 version = vcpu_to_pmu(vcpu)->version; + + if (!intel_pmu_lbr_is_enabled(vcpu)) + return; + + if (version > 1 && version < 4) + intel_pmu_legacy_freezing_lbrs_on_pmi(vcpu); +} + static void vmx_update_intercept_for_lbr_msrs(struct kvm_vcpu *vcpu, bool set) { struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu); @@ -672,4 +701,5 @@ struct kvm_pmu_ops intel_pmu_ops = { .refresh = intel_pmu_refresh, .init = intel_pmu_init, .reset = intel_pmu_reset, + .deliver_pmi = intel_pmu_deliver_pmi, }; |