[RFC PATCH] powerpc/mm: Return NULL for not present hugetlb page

[Aneesh Kumar K.V]

Benjamin Herrenschmidt <benh at kernel.crashing.org> writes:

> On Thu, 2015-05-07 at 12:46 +0530, Aneesh Kumar K.V wrote:
>> We need to check whether pte is present in follow_huge_addr and
>> properly return NULL if mapping is not present. Also use READ_ONCE
>> when dereferencing pte_t address.
>
> Do that need to go to stable as well ?

Yes. I will like David to take a look at this and give his feedback.
W.r.t patch itself I hit a build failure on mpc85xx_smp_defconfig. I will
resent after the test build finish on all configs

-aneesh