[PATCH for 5.10] powerpc/32s: Fix RTAS machine check with VMAP stack

[Sasha Levin]

On Wed, Jan 13, 2021 at 06:40:20AM +0000, Christophe Leroy wrote:
>This is backport for 5.10
>
>(cherry picked from commit 98bf2d3f4970179c702ef64db658e0553bc6ef3a)
>
>When we have VMAP stack, exception prolog 1 sets r1, not r11.
>
>When it is not an RTAS machine check, don't trash r1 because it is
>needed by prolog 1.
>
>Fixes: da7bb43ab9da ("powerpc/32: Fix vmap stack - Properly set r1 before activating MMU")
>Cc: stable at vger.kernel.org # v5.10+
>Signed-off-by: Christophe Leroy <christophe.leroy at csgroup.eu>
>[mpe: Squash in fixup for RTAS machine check from Christophe]
>Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>
>Link: https://lore.kernel.org/r/bc77d61d1c18940e456a2dee464f1e2eda65a3f0.1608621048.git.christophe.leroy@csgroup.eu

Queued up, thanks!

-- 
Thanks,
Sasha