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Date:   Mon, 18 Oct 2021 14:27:31 +0200
From:   Michal Hocko <mhocko@suse.com>
To:     Vasily Averin <vvs@virtuozzo.com>
Cc:     Johannes Weiner <hannes@cmpxchg.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Roman Gushchin <guro@fb.com>,
        Uladzislau Rezki <urezki@gmail.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Shakeel Butt <shakeelb@google.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        cgroups@vger.kernel.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, kernel@openvz.org
Subject: Re: [PATCH memcg 0/1] false global OOM triggered by memcg-limited
 task
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On Mon 18-10-21 15:14:26, Vasily Averin wrote:
> On 18.10.2021 14:53, Michal Hocko wrote:
> > On Mon 18-10-21 13:05:35, Vasily Averin wrote:
> >> On 18.10.2021 12:04, Michal Hocko wrote:
> >> Here we call try_charge_memcg() that return success and approve the allocation,
> >> however then we hit into kmem limit and fail the allocation.
> > 
> > Just to make sure I understand this would be for the v1 kmem explicit
> > limit, correct?
> 
> yes, I mean this limit.

OK, thanks for the clarification. This is a known problem. Have a look
at I think we consider that one to 0158115f702b ("memcg, kmem: deprecate
kmem.limit_in_bytes"). We are reporting the deprecated and to-be removed
status since 2019 without any actual report sugested by the kernel
message. Maybe we should try and remove it and see whether that prompts
some pushback.

-- 
Michal Hocko
SUSE Labs