[PATCH/RFC] powerpc: Better handle "error" type page faults on book3s64

[Balbir Singh]

On Fri, 2017-07-14 at 18:31 +1000, Benjamin Herrenschmidt wrote:
> There are a number of conditions in the DSISR that represent
> conditions for which there is no point looking for a VMA or
> trying to update a PTE. In fact, POWER9 adds a few with bad
> AMOs, bad "paste" instruction etc...
> 
> This improve our existing code to use symbolic constants for
> all DSISR bits, properly avoid hash_page() for the new bits,
> and handle both the old and new bits early in do_page_fault()
> 
> Signed-off-by: Benjamin Herrenschmidt <benh at kernel.crashing.org>
> --
>

Looks reasonable

Acked-by: Balbir Singh <bsingharora at gmail.com>