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

From: Anshuman Khandual
Date: Mon Nov 28 2022 - 08:57:20 EST


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@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: linux-perf-users@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
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