Hi Catalin,
> On Thu, Apr 10, 2025 at 08:47:19AM +0100, Yeoreum Yun wrote:
> > Add FEAT_MTE_TAGGED_FAR cpucap which makes FAR_ELx report
> > all non-address bits on a synchronous MTE tag check fault since Armv8.9
> >
> > Signed-off-by: Yeoreum Yun <yeoreum.yun@xxxxxxx>
> > Acked-by: Yury Khrustalev <yury.khrustalev@xxxxxxx>
> [...]
> > @@ -3191,6 +3199,7 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
> > #ifdef CONFIG_ARM64_MTE
> > HWCAP_CAP(ID_AA64PFR1_EL1, MTE, MTE2, CAP_HWCAP, KERNEL_HWCAP_MTE),
> > HWCAP_CAP(ID_AA64PFR1_EL1, MTE, MTE3, CAP_HWCAP, KERNEL_HWCAP_MTE3),
> > + HWCAP_CAP(ID_AA64PFR2_EL1, MTEFAR, IMP, CAP_HWCAP, KERNEL_HWCAP_MTE_FAR),
>
> Nitpick: from a theoretical bisectability perspective, I'd move the
> hwcap exposing to the following patch. The rest, feature detection etc
> can stay in this file. Otherwise, one can apply this patch, see the
> hwcap but not get the actual behaviour.
Thanks. I'll squash realted HWCAP to followin patch.
> > #endif /* CONFIG_ARM64_MTE */
> > HWCAP_CAP(ID_AA64MMFR0_EL1, ECV, IMP, CAP_HWCAP, KERNEL_HWCAP_ECV),
> > HWCAP_CAP(ID_AA64MMFR1_EL1, AFP, IMP, CAP_HWCAP, KERNEL_HWCAP_AFP),
> > diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
> > index 285d7d538342..e2b13454e38a 100644
> > --- a/arch/arm64/kernel/cpuinfo.c
> > +++ b/arch/arm64/kernel/cpuinfo.c
> > @@ -160,6 +160,7 @@ static const char *const hwcap_str[] = {
> > [KERNEL_HWCAP_SME_SFEXPA] = "smesfexpa",
> > [KERNEL_HWCAP_SME_STMOP] = "smestmop",
> > [KERNEL_HWCAP_SME_SMOP4] = "smesmop4",
> > + [KERNEL_HWCAP_MTE_FAR] = "mte_far",
>
> Personal preference: "mtefar" (no underscore), mostly because there's no
> other underscore in the hwcap strings yet ;).
Thanks. I'll change it!
--
Sincerely,
Yeoreum Yun
