Re: [PATCH v4] arm64: errata: Work around AmpereOne's erratum AC04_CPU_23
From: Will Deacon
Date: Mon May 19 2025 - 07:13:29 EST
On Mon, May 19, 2025 at 11:56:51AM +0100, Catalin Marinas wrote:
> On Tue, May 13, 2025 at 11:45:14AM -0700, D Scott Phillips wrote:
> > On AmpereOne AC04, updates to HCR_EL2 can rarely corrupt simultaneous
> > translations for data addresses initiated by load/store instructions.
> > Only instruction initiated translations are vulnerable, not translations
> > from prefetches for example. A DSB before the store to HCR_EL2 is
> > sufficient to prevent older instructions from hitting the window for
> > corruption, and an ISB after is sufficient to prevent younger
> > instructions from hitting the window for corruption.
> >
> > Signed-off-by: D Scott Phillips <scott@xxxxxxxxxxxxxxxxxxxxxx>
> > Reviewed-by: Oliver Upton <oliver.upton@xxxxxxxxx>
>
> For the core arm64 bits:
>
> Acked-by: Catalin Marinas <catalin.marinas@xxxxxxx>
>
> Marc, Will - any preference on how this should go in (kvm or arm64
> trees)?
I think it makes most sense to go via the kvm tree based on the diffstat.
Cheers,
Will