Re: powerpc: Fix DAR reporting when alignment handler faults

On Thu, 2017-08-24 at 10:49:57 UTC, Michael Ellerman wrote:

Anton noticed that if we fault part way through emulating an unaligned
instruction, we don't update the DAR to reflect that.

The DAR value is eventually reported back to userspace as the address
in the SEGV signal, and if userspace is using that value to demand
fault then it can be confused by us not setting the value correctly.

This patch is ugly as hell, but is intended to be the minimal fix and
back ports easily.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Applied to powerpc next.

https://git.kernel.org/powerpc/c/f9effe925039cf54489b5c04e0d400

cheers