On Thu, May 14, 2020 at 04:30:50PM +0800, Like Xu wrote: > @@ -203,6 +206,12 @@ static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > case MSR_CORE_PERF_GLOBAL_OVF_CTRL: > msr_info->data = pmu->global_ovf_ctrl; > return 0; > + case MSR_IA32_PERF_CAPABILITIES: > + if (!msr_info->host_initiated && > + !guest_cpuid_has(vcpu, X86_FEATURE_PDCM)) > + return 1; I know this is KVM code, so maybe they feel differently, but I find the above indentation massively confusing. Consider using: "set cino=:0(0" if you're a vim user. > + msr_info->data = vcpu->arch.perf_capabilities; > + return 0; > default: > if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0))) { > u64 val = pmc_read_counter(pmc); > @@ -261,6 +270,16 @@ static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > return 0; > } > break; > + case MSR_IA32_PERF_CAPABILITIES: > + if (!msr_info->host_initiated || > + !guest_cpuid_has(vcpu, X86_FEATURE_PDCM)) > + return 1; Idem. > + if (!(data & ~vmx_get_perf_capabilities())) > + return 1; > + if ((data ^ vmx_get_perf_capabilities()) & PERF_CAP_LBR_FMT) > + return 1; > + vcpu->arch.perf_capabilities = data; > + return 0; > default: > if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0))) { > if (!msr_info->host_initiated)