powerpc/mm: Fix crash in page table dump with huge pages

[Michael Ellerman]

On Tue, 2017-05-16 at 10:50:35 UTC, Michael Ellerman wrote:
> The page table dump code doesn't know about huge pages, so currently
> it crashes (or walks random memory, usually leading to a crash), if it
> finds a huge page. On Book3S we only see huge pages in the Linux page
> tables when we're using the P9 Radix MMU.
> 
> Teaching the code to properly handle huge pages is a bit more involved,
> so for now just prevent the crash.
> 
> Cc: stable at vger.kernel.org # v4.10+
> Fixes: 8eb07b187000 ("powerpc/mm: Dump linux pagetables")
> Signed-off-by: Michael Ellerman <mpe at ellerman.id.au>

Applied to powerpc fixes.

https://git.kernel.org/powerpc/c/bfb9956ab4d8242f4594b5f4bee534

cheers