Re: [PATCH] arm64: Add workaround for Cavium erratum 27456

From: Marc Zyngier
Date: Tue Feb 09 2016 - 15:07:26 EST


On Tue, 9 Feb 2016 11:59:10 -0800
David Daney <ddaney@xxxxxxxxxxxxxxxxxx> wrote:

> On 02/09/2016 11:52 AM, Marc Zyngier wrote:
> > On Tue, 9 Feb 2016 11:29:16 -0800
> > David Daney <ddaney.cavm@xxxxxxxxx> wrote:
> >
> > Hi David,
> >
> >> From: Andrew Pinski <apinski@xxxxxxxxxx>
> >>
> >> On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
> >> instructions may cause the icache to become invalid if it contains
> >> data for a non-current ASID.
> >>
> >> This patch implements the workaround (which flushes the local icache
> >> when switching the mm) by using code patching.
> >>
> >> Signed-off-by: Andrew Pinski <apinski@xxxxxxxxxx>
> >> Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
> >> ---
> >> arch/arm64/Kconfig | 11 +++++++++++
> >> arch/arm64/include/asm/cpufeature.h | 3 ++-
> >> arch/arm64/kernel/cpu_errata.c | 9 +++++++++
> >> arch/arm64/mm/proc.S | 12 ++++++++++++
> >> 4 files changed, 34 insertions(+), 1 deletion(-)
> >
> > It would be good to update Documentation/arm64/silicon-errata.txt to
> > reflect the fact that there is a workaround available for this erratum.
>
> Would you prefer a separate patch for that, or should I roll it into
> this one and resubmit?

It'd feel more logical to keep it all together, but I'll leave that
decision to Catalin and Will.

Thanks,

M.
--
Jazz is not dead. It just smells funny.