On 27/04/20 09:19, Like Xu wrote: > + if (vmx_supported_perf_capabilities()) > + kvm_cpu_cap_check_and_set(X86_FEATURE_PDCM); I think we can always set it, worst case it will be zero. However, blocking intel_pmu_set_msr altogether is incorrect. Instead, you need to: - list the MSR in msr_based_features_all so that it appears in KVM_GET_MSR_FEATURE_INDEX_LIST - return the supported bits in vmx_get_msr_feature - allow host-initiated writes (as long as they only set supported bits) of the MSR in intel_pmu_set_msr. Thanks, Paolo
