[PATCH] KVM: arm64: Replace PMU version number '0' with ID_AA64DFR0_EL1_PMUVer_NI

Anshuman Khandual anshuman.khandual at arm.com
Mon Nov 28 05:56:29 PST 2022


kvm_host_pmu_init() returns when detected PMU is either not implemented, or
implementation defined. kvm_pmu_probe_armpmu() also has a similar situation
Extracted ID_AA64DFR0_EL1_PMUVer value, when PMU is not implemented is '0',
which can be replaced with ID_AA64DFR0_EL1_PMUVer_NI defined as '0b0000'.

Cc: Arnaldo Carvalho de Melo <acme at kernel.org>
Cc: Marc Zyngier <maz at kernel.org>
Cc: Mark Rutland <mark.rutland at arm.com>
Cc: Will Deacon <will at kernel.org>
Cc: Catalin Marinas <catalin.marinas at arm.com>
Cc: linux-perf-users at vger.kernel.org
Cc: linux-kernel at vger.kernel.org
Cc: linux-arm-kernel at lists.infradead.org
Signed-off-by: Anshuman Khandual <anshuman.khandual at arm.com>
---
This applies on v6.1-rc6

 arch/arm64/kvm/pmu-emul.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c
index 0003c7d37533..089a0b4c561b 100644
--- a/arch/arm64/kvm/pmu-emul.c
+++ b/arch/arm64/kvm/pmu-emul.c
@@ -774,7 +774,8 @@ void kvm_host_pmu_init(struct arm_pmu *pmu)
 {
 	struct arm_pmu_entry *entry;
 
-	if (pmu->pmuver == 0 || pmu->pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF)
+	if (pmu->pmuver == ID_AA64DFR0_EL1_PMUVer_NI ||
+	    pmu->pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF)
 		return;
 
 	mutex_lock(&arm_pmus_lock);
@@ -827,7 +828,7 @@ static struct arm_pmu *kvm_pmu_probe_armpmu(void)
 
 	if (event->pmu) {
 		pmu = to_arm_pmu(event->pmu);
-		if (pmu->pmuver == 0 ||
+		if (pmu->pmuver == ID_AA64DFR0_EL1_PMUVer_NI ||
 		    pmu->pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF)
 			pmu = NULL;
 	}
-- 
2.25.1




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