[PATCH v2 10/23] KVM: arm64: Correct kvm_arm_pmu_get_max_counters()

Colton Lewis coltonlewis at google.com
Fri Jun 20 15:13:11 PDT 2025


Since cntr_mask is modified when the PMU is partitioned to remove some
bits, make sure the missing counters are added back to get the right
total.

Signed-off-by: Colton Lewis <coltonlewis at google.com>
---
 arch/arm64/kvm/pmu.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kvm/pmu.c b/arch/arm64/kvm/pmu.c
index 79b7ea037153..67216451b8ce 100644
--- a/arch/arm64/kvm/pmu.c
+++ b/arch/arm64/kvm/pmu.c
@@ -533,6 +533,8 @@ static bool pmu_irq_is_valid(struct kvm *kvm, int irq)
 u8 kvm_arm_pmu_get_max_counters(struct kvm *kvm)
 {
 	struct arm_pmu *arm_pmu = kvm->arch.arm_pmu;
+	u8 counters;
+
 
 	/*
 	 * PMUv3 requires that all event counters are capable of counting any
@@ -545,7 +547,12 @@ u8 kvm_arm_pmu_get_max_counters(struct kvm *kvm)
 	 * The arm_pmu->cntr_mask considers the fixed counter(s) as well.
 	 * Ignore those and return only the general-purpose counters.
 	 */
-	return bitmap_weight(arm_pmu->cntr_mask, ARMV8_PMU_MAX_GENERAL_COUNTERS);
+	counters = bitmap_weight(arm_pmu->cntr_mask, ARMV8_PMU_MAX_GENERAL_COUNTERS);
+
+	if (kvm_pmu_is_partitioned(arm_pmu))
+		counters += arm_pmu->hpmn_max;
+
+	return counters;
 }
 
 static void kvm_arm_set_nr_counters(struct kvm *kvm, unsigned int nr)
-- 
2.50.0.714.g196bf9f422-goog




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