On Fri, 2018-03-23 at 05:53:38 UTC, Nicholas Piggin wrote:
> The SLB bad address handler's trap number fixup does not preserve the
> low bit that indicates nonvolatile GPRs have not been saved. This
> leads save_nvgprs to skip saving them, and subsequent functions and
> return from interrupt will think they are saved.
>
> This causes kernel branch-to-garbage debugging to not have correct
> registers, can also cause userspace to have its registers clobbered
> after a segfault.
>
> Fixes: f0f558b131 ("powerpc/mm: Preserve CFAR value on SLB miss caused by
> access to bogus address")
> Cc: Paul Mackerras <pau...@ozlabs.org>
> Signed-off-by: Nicholas Piggin <npig...@gmail.com>
I added:
Cc: sta...@vger.kernel.org # v4.9+
Applied to powerpc fixes, thanks.
https://git.kernel.org/powerpc/c/52396500f97c53860164debc7d4f75
cheers
