linux-kernel - [PATCH v4 2/5] KVM: selftests: Track unavailable

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Message-ID: <20250919214648.1585683-3-seanjc@google.com>
Date: Fri, 19 Sep 2025 14:46:45 -0700
From: Sean Christopherson <seanjc@...gle.com>
To: Sean Christopherson <seanjc@...gle.com>, Paolo Bonzini <pbonzini@...hat.com>
Cc: kvm@...r.kernel.org, linux-kernel@...r.kernel.org, 
	Dapeng Mi <dapeng1.mi@...ux.intel.com>, Yi Lai <yi1.lai@...el.com>
Subject: [PATCH v4 2/5] KVM: selftests: Track unavailable_mask for PMU events
 as 32-bit value

Track the mask of "unavailable" PMU events as a 32-bit value.  While bits
31:9 are currently reserved, silently truncating those bits is unnecessary
and asking for missed coverage.  To avoid running afoul of the sanity check
in vcpu_set_cpuid_property(), explicitly adjust the mask based on the
non-reserved bits as reported by KVM's supported CPUID.

Opportunistically update the "all ones" testcase to pass -1u instead of
0xff.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 tools/testing/selftests/kvm/x86/pmu_counters_test.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/x86/pmu_counters_test.c b/tools/testing/selftests/kvm/x86/pmu_counters_test.c
index 8aaaf25b6111..1ef038c4c73f 100644
--- a/tools/testing/selftests/kvm/x86/pmu_counters_test.c
+++ b/tools/testing/selftests/kvm/x86/pmu_counters_test.c
@@ -311,7 +311,7 @@ static void guest_test_arch_events(void)
 }
 
 static void test_arch_events(uint8_t pmu_version, uint64_t perf_capabilities,
-			     uint8_t length, uint8_t unavailable_mask)
+			     uint8_t length, uint32_t unavailable_mask)
 {
 	struct kvm_vcpu *vcpu;
 	struct kvm_vm *vm;
@@ -320,6 +320,9 @@ static void test_arch_events(uint8_t pmu_version, uint64_t perf_capabilities,
 	if (!pmu_version)
 		return;
 
+	unavailable_mask &= GENMASK(X86_PROPERTY_PMU_EVENTS_MASK.hi_bit,
+				    X86_PROPERTY_PMU_EVENTS_MASK.lo_bit);
+
 	vm = pmu_vm_create_with_one_vcpu(&vcpu, guest_test_arch_events,
 					 pmu_version, perf_capabilities);
 
@@ -630,7 +633,7 @@ static void test_intel_counters(void)
 			 */
 			for (j = 0; j <= NR_INTEL_ARCH_EVENTS + 1; j++) {
 				test_arch_events(v, perf_caps[i], j, 0);
-				test_arch_events(v, perf_caps[i], j, 0xff);
+				test_arch_events(v, perf_caps[i], j, -1u);
 
 				for (k = 0; k < NR_INTEL_ARCH_EVENTS; k++)
 					test_arch_events(v, perf_caps[i], j, BIT(k));
-- 
2.51.0.470.ga7dc726c21-goog