[PATCH] arm64: Add workaround for Cavium erratum 27456

[Will Deacon]

On Tue, Feb 09, 2016 at 11:29:16AM -0800, David Daney wrote:
> From: Andrew Pinski <apinski at cavium.com>
> 
> 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.

So, to be clear, is this "just" a performance problem as opposed to a
correctness issue? If so, do you have any numbers with and without this
change?

Will