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

From: Marc Zyngier
Date: Tue Feb 09 2016 - 14:52:33 EST


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.

Thanks,

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