[PATCH v8 1/7] kvm: x86/pmu: Correct the mask used in a pmu event filter lookup

[Aaron Lewis <aaronlewis@google.com>]

When checking if a pmu event the guest is attempting to program should
be filtered, only consider the event select + unit mask in that
decision. Use an architecture specific mask to mask out all other bits,
including bits 35:32 on Intel.  Those bits are not part of the event
select and should not be considered in that decision.

Fixes: 66bb8a065f5a ("KVM: x86: PMU Event Filter")
Signed-off-by: Aaron Lewis <aaronlewis@google.com>
---
 arch/x86/kvm/pmu.c           | 3 ++-
 arch/x86/kvm/pmu.h           | 2 ++
 arch/x86/kvm/svm/pmu.c       | 1 +
 arch/x86/kvm/vmx/pmu_intel.c | 1 +
 4 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index 684393c22105..760a09ff65cd 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -277,7 +277,8 @@ static bool check_pmu_event_filter(struct kvm_pmc *pmc)
 		goto out;
 
 	if (pmc_is_gp(pmc)) {
-		key = pmc->eventsel & AMD64_RAW_EVENT_MASK_NB;
+		key = pmc->eventsel & (kvm_pmu_ops.EVENTSEL_EVENT |
+				       ARCH_PERFMON_EVENTSEL_UMASK);
 		if (bsearch(&key, filter->events, filter->nevents,
 			    sizeof(__u64), cmp_u64))
 			allow_event = filter->action == KVM_PMU_EVENT_ALLOW;
diff --git a/arch/x86/kvm/pmu.h b/arch/x86/kvm/pmu.h
index 85ff3c0588ba..5b070c563a97 100644
--- a/arch/x86/kvm/pmu.h
+++ b/arch/x86/kvm/pmu.h
@@ -40,6 +40,8 @@ struct kvm_pmu_ops {
 	void (*reset)(struct kvm_vcpu *vcpu);
 	void (*deliver_pmi)(struct kvm_vcpu *vcpu);
 	void (*cleanup)(struct kvm_vcpu *vcpu);
+
+	const u64 EVENTSEL_EVENT;
 };
 
 void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops);
diff --git a/arch/x86/kvm/svm/pmu.c b/arch/x86/kvm/svm/pmu.c
index 0e313fbae055..d3ae261d56a6 100644
--- a/arch/x86/kvm/svm/pmu.c
+++ b/arch/x86/kvm/svm/pmu.c
@@ -229,4 +229,5 @@ struct kvm_pmu_ops amd_pmu_ops __initdata = {
 	.refresh = amd_pmu_refresh,
 	.init = amd_pmu_init,
 	.reset = amd_pmu_reset,
+	.EVENTSEL_EVENT = AMD64_EVENTSEL_EVENT,
 };
diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index e5cec07ca8d9..edf23115f2ef 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -810,4 +810,5 @@ struct kvm_pmu_ops intel_pmu_ops __initdata = {
 	.reset = intel_pmu_reset,
 	.deliver_pmi = intel_pmu_deliver_pmi,
 	.cleanup = intel_pmu_cleanup,
+	.EVENTSEL_EVENT = ARCH_PERFMON_EVENTSEL_EVENT,
 };
-- 
2.39.0.314.g84b9a713c41-goog