[PATCH 0/2] KVM: x86/pmu: Fix a fixed PMC event filter bypass bug

From: Sean Christopherson

Date: Wed Jun 03 2026 - 19:19:40 EST


Fix a bug reported by Sashiko, where KVM will effectively ignore PMU event
filters for fixed counters if FIXED_CTR_CTRL is changing, but enable bits
for denied counters are NOT changing.

Sean Christopherson (2):
KVM: x86/pmu: Use hardware value when reprogramming for FIXED_CTR_CTRL
changes
KVM: selftests: Add regression test for mediated PMU fixed counter
filter bug

arch/x86/kvm/vmx/pmu_intel.c | 10 +++++++++-
.../testing/selftests/kvm/x86/pmu_event_filter_test.c | 6 ++++++
2 files changed, 15 insertions(+), 1 deletion(-)


base-commit: d4bfaa66fa171089b9b9fb2dc17af9245f2b9b34
--
2.54.0.1032.g2f8565e1d1-goog