diff options
| author | Oliver Upton <oliver.upton@linux.dev> | 2025-03-05 12:26:37 -0800 |
|---|---|---|
| committer | Oliver Upton <oliver.upton@linux.dev> | 2025-03-11 12:54:29 -0700 |
| commit | bed9b8ec8c71135c59004d12658d8affe232f27e (patch) | |
| tree | 92e307b6ff000d0cd52ff48675f0c591750c4712 | |
| parent | 2c433f70dccc1af6922931404bfe23d215bdfff0 (diff) | |
KVM: arm64: Advertise PMUv3 if IMPDEF traps are present
Advertise a baseline PMUv3 implementation when running on hardware with
IMPDEF traps of the PMUv3 sysregs.
Tested-by: Janne Grunau <j@jannau.net>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250305202641.428114-11-oliver.upton@linux.dev
Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
| -rw-r--r-- | arch/arm64/kvm/pmu-emul.c | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 0a2023aabe18..38d9490c17fd 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -1231,7 +1231,17 @@ u8 kvm_arm_pmu_get_pmuver_limit(void) pmuver = SYS_FIELD_GET(ID_AA64DFR0_EL1, PMUVer, read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1)); - /* Treat IMPLEMENTATION DEFINED functionality as unimplemented */ + /* + * Spoof a barebones PMUv3 implementation if the system supports IMPDEF + * traps of the PMUv3 sysregs + */ + if (cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS)) + return ID_AA64DFR0_EL1_PMUVer_IMP; + + /* + * Otherwise, treat IMPLEMENTATION DEFINED functionality as + * unimplemented + */ if (pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF) return 0; |