Hi Marc, Tested on FVP and the nasty splat goes away, so it works for me: Tested-by: Alexandru Elisei <alexandru.elisei@xxxxxxx> The guest visible PMCR_EL0.FZ0 bit added by FEAT_PMUv3p7 is cleared on register reset/write because ARMV8_PMU_PMCR_MASK is 0xff. This makes the bit behave as RES0, which is the architectural value for the field when FEAT_PMUv3p7 is absent. So the patch looks correct to me: Reviewed-by: Alexandru Elisei <alexandru.elisei@xxxxxxx> Thanks, Alex On Fri, Nov 26, 2021 at 11:55:33AM +0000, Marc Zyngier wrote: > When running a KVM guest hosted on an ARMv8.7 machine, the host > kernel complains that it doesn't know about the architected number > of events. > > Fix it by adding the PMUver code corresponding to PMUv3 for ARMv8.7. > > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> > --- > arch/arm64/include/asm/sysreg.h | 1 + > arch/arm64/kvm/pmu-emul.c | 1 + > 2 files changed, 2 insertions(+) > > diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h > index cdb590840b3f..5de90138d0a4 100644 > --- a/arch/arm64/include/asm/sysreg.h > +++ b/arch/arm64/include/asm/sysreg.h > @@ -1036,6 +1036,7 @@ > #define ID_AA64DFR0_PMUVER_8_1 0x4 > #define ID_AA64DFR0_PMUVER_8_4 0x5 > #define ID_AA64DFR0_PMUVER_8_5 0x6 > +#define ID_AA64DFR0_PMUVER_8_7 0x7 > #define ID_AA64DFR0_PMUVER_IMP_DEF 0xf > > #define ID_AA64DFR0_PMSVER_8_2 0x1 > diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c > index a5e4bbf5e68f..ca92cc5c71c6 100644 > --- a/arch/arm64/kvm/pmu-emul.c > +++ b/arch/arm64/kvm/pmu-emul.c > @@ -28,6 +28,7 @@ static u32 kvm_pmu_event_mask(struct kvm *kvm) > case ID_AA64DFR0_PMUVER_8_1: > case ID_AA64DFR0_PMUVER_8_4: > case ID_AA64DFR0_PMUVER_8_5: > + case ID_AA64DFR0_PMUVER_8_7: > return GENMASK(15, 0); > default: /* Shouldn't be here, just for sanity */ > WARN_ONCE(1, "Unknown PMU version %d\n", kvm->arch.pmuver); > -- > 2.30.2 > _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
