Re: [RFC] mm/mremap: Remove redundant checks inside vma_expandable()

From: Anshuman Khandual
Date: Tue Jul 11 2017 - 07:19:27 EST

On 07/11/2017 12:52 PM, Michal Hocko wrote:
> On Tue 11-07-17 09:16:12, Michal Hocko wrote:
>> On Tue 11-07-17 08:56:04, Vlastimil Babka wrote:
> [...]
>>> It doesn't explain why it's redundant, indeed. Unfortunately, the commit
>>> f106af4e90ea ("fix checks for expand-in-place mremap") which added this,
>>> also doesn't explain why it's needed.
>> Because it doesn't do anything AFAICS.
> Well, it does actually. I have missed security_mmap_addr hook.

But we any way call get_unmapped_area() down the line in the function,
it should be covered then. Does the proposed change look good and be
considered, or any changes required or can be dropped ?