Hi Chase, On Mon, 09 Dec 2024 14:24:29 +0000, Chase Conklin <chase.conklin@xxxxxxx> wrote: > > Hi Marc, > > On Mon, 2 Dec 2024 17:21:23 +0000, Marc Zyngier <maz@xxxxxxxxxx> > wrote: > > > If you are feeling brave, you can run the whole thing from [1]. > > > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=kvm-arm64/nv-next > > > > I was feeling brave, and I think I see an issue in the cpufeature change > in the kvm-arm64/nv-e2h-select branch that's a part of > kvm-arm64/nv-next. In d75a4820a897 ("arm64: cpufeature: Handle NV_frac as a synonym of NV2"), > I don't see NV_frac being added to the FTR bits. I believe that means it > will get sanitized out and consequently not seen by the NV feature > detection code. Does that commit also need: > > diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c > index 9fa8bd77ae0..f97459e160b 100644 > --- a/arch/arm64/kernel/cpufeature.c > +++ b/arch/arm64/kernel/cpufeature.c > @@ -480,6 +480,7 @@ static const struct arm64_ftr_bits ftr_id_aa64mmfr3[] = { > > static const struct arm64_ftr_bits ftr_id_aa64mmfr4[] = { > S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR4_EL1_E2H0_SHIFT, 4, 0), > + S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR4_EL1_NV_frac_SHIFT, 4, 0), > ARM64_FTR_END, > }; Ah, I always get tripped by that one. You are absolutely correct, this is needed. I'll fold that in. Thanks again, M. -- Without deviation from the norm, progress is not possible.
