Re: [PATCH 7/8] arm64: cpufeature: Relax checks for AArch32 support at EL[0-2]

From: Will Deacon
Date: Wed Apr 15 2020 - 07:01:43 EST


On Wed, Apr 15, 2020 at 11:50:58AM +0100, Suzuki K Poulose wrote:
> On 04/14/2020 10:31 PM, Will Deacon wrote:
> > We don't need to be quite as strict about mismatched AArch32 support,
> > which is good because the friendly hardware folks have been busy
> > mismatching this to their hearts' content.
> >
> > * We don't care about EL2 or EL3 (there are silly comments concerning
> > the latter, so remove those)
> >
> > * EL1 support is gated by the ARM64_HAS_32BIT_EL1 capability and handled
> > gracefully when a mismatch occurs
> >
> > * EL1 support is gated by the ARM64_HAS_32BIT_EL0 capability and handled
>
> s/EL1/EL0
>
> > gracefully when a mismatch occurs
> >
> > Relax the AArch32 checks to FTR_NONSTRICT.
>
> Agreed. We should do something similar for the features exposed by the
> ELF_HWCAP, of course in a separate series.

Hmm, I didn't think we needed to touch the HWCAPs, as they're derived from
the sanitised feature register values. What am I missing?

Will