Re: [PATCH] mm, memcg: fix mem_cgroup_swapout() for THPs

From: Shakeel Butt
Date: Tue Nov 28 2017 - 15:09:31 EST


On Tue, Nov 28, 2017 at 12:00 PM, Michal Hocko <mhocko@xxxxxxxxxx> wrote:
> On Tue 28-11-17 08:19:41, Shakeel Butt wrote:
>> The commit d6810d730022 ("memcg, THP, swap: make mem_cgroup_swapout()
>> support THP") changed mem_cgroup_swapout() to support transparent huge
>> page (THP). However the patch missed one location which should be
>> changed for correctly handling THPs. The resulting bug will cause the
>> memory cgroups whose THPs were swapped out to become zombies on
>> deletion.
>
> Very well spotted! Have you seen this triggering or you found it by the
> code inspection?
>

By code inspection.