If the guest disables the counter (by clearing ARCH_PERFMON_EVENTSEL_ENABLE), KVM still performs the PMU filter lookup, even though it doesn't end up changing eventsel_hw. Check if the counter is enabled by the guest before doing the potentially expensive PMU filter lookup. Suggested-by: Sean Christopherson Signed-off-by: Yosry Ahmed --- arch/x86/kvm/pmu.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c index afbc731e72174..67dbbd4c73036 100644 --- a/arch/x86/kvm/pmu.c +++ b/arch/x86/kvm/pmu.c @@ -532,7 +532,7 @@ static bool pmc_is_event_allowed(struct kvm_pmc *pmc) static void kvm_mediated_pmu_refresh_event_filter(struct kvm_pmc *pmc) { - bool allowed = pmc_is_event_allowed(pmc); + bool allowed = pmc_is_locally_enabled(pmc) && pmc_is_event_allowed(pmc); struct kvm_pmu *pmu = pmc_to_pmu(pmc); if (pmc_is_gp(pmc)) { -- 2.54.0.794.g4f17f83d09-goog