The ARM architecture specifies that when MDCR_EL2.HPMN is set, EL1 and EL0, which includes KVM guests, should read that value for PMCR.N.
Signed-off-by: Colton Lewis coltonlewis@google.com --- arch/arm64/kvm/pmu-emul.c | 8 +++++++- tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c | 2 +- 2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 6c5950b9ceac..052ce8c721fe 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -993,12 +993,18 @@ 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 limit; + + if (arm_pmu->partitioned) + limit = arm_pmu->hpmn - 1; + else + limit = ARMV8_PMU_MAX_GENERAL_COUNTERS;
/* * 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); + return bitmap_weight(arm_pmu->cntr_mask, limit); }
static void kvm_arm_set_pmu(struct kvm *kvm, struct arm_pmu *arm_pmu) diff --git a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c index f9c0c86d7e85..4d5acdb66bc2 100644 --- a/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c +++ b/tools/testing/selftests/kvm/aarch64/vpmu_counter_access.c @@ -610,7 +610,7 @@ static void run_pmregs_validity_test(uint64_t pmcr_n) */ static void run_error_test(uint64_t pmcr_n) { - pr_debug("Error test with pmcr_n %lu (larger than the host)\n", pmcr_n); + pr_debug("Error test with pmcr_n %lu (larger than the host allows)\n", pmcr_n);
test_create_vpmu_vm_with_pmcr_n(pmcr_n, true); destroy_vpmu_vm();