[PATCH 1/2] KVM: x86/pmu: Prevent the PMU from counting disallowed events

[Aaron Lewis <aaronlewis@google.com>]

When counting "Instructions Retired" (0xc0) in a guest, KVM will
occasionally increment the PMU counter regardless of if that event is
being filtered. This is because some PMU events are incremented via
kvm_pmu_trigger_event(), which doesn't know about the event filter. Add
the event filter to kvm_pmu_trigger_event(), so events that are
disallowed do not increment their counters.

Fixes: 9cd803d496e7 ("KVM: x86: Update vPMCs when retiring instructions")
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
---
 arch/x86/kvm/pmu.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 684393c22105..b87cf35a38b7 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -581,7 +581,9 @@ void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 perf_hw_id)
 	for_each_set_bit(i, pmu->all_valid_pmc_idx, X86_PMC_IDX_MAX) {
 		pmc = static_call(kvm_x86_pmu_pmc_idx_to_pmc)(pmu, i);
 
-		if (!pmc || !pmc_is_enabled(pmc) || !pmc_speculative_in_use(pmc))
+		if (!pmc || !pmc_is_enabled(pmc) ||
+		    !pmc_speculative_in_use(pmc) ||
+		    !check_pmu_event_filter(pmc))
 			continue;
 
 		/* Ignore checks for edge detect, pin control, invert and CMASK bits */
-- 
2.39.0.rc1.256.g54fd8350bd-goog