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Date:   Fri, 2 Dec 2022 16:50:27 -0800
From:   Andrew Morton <akpm@linux-foundation.org>
To:     Yosry Ahmed <yosryahmed@google.com>
Cc:     Shakeel Butt <shakeelb@google.com>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@suse.com>, Yu Zhao <yuzhao@google.com>,
        Muchun Song <songmuchun@bytedance.com>,
        Tejun Heo <tj@kernel.org>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        Vasily Averin <vasily.averin@linux.dev>,
        Vlastimil Babka <vbabka@suse.cz>,
        Chris Down <chris@chrisdown.name>,
        David Rientjes <rientjes@google.com>, cgroups@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org
Subject: Re: [PATCH v3 1/3] mm: memcg: fix stale protection of reclaim
 target memcg
Message-Id: <20221202165027.8d0761724f30f6701a9a5da0@linux-foundation.org>
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On Fri, 2 Dec 2022 16:38:12 -0800 Yosry Ahmed <yosryahmed@google.com> wrote:

> On Fri, Dec 2, 2022 at 4:35 PM Andrew Morton <akpm@linux-foundation.org> wrote:
> >
> > On Fri, 2 Dec 2022 16:26:05 -0800 Yosry Ahmed <yosryahmed@google.com> wrote:
> >
> > > Andrew, does this need to be picked up by stable branches?
> >
> > Does it?  The changelog doesn't have a clear description of the
> > user-visible effects of the flaw, which is the guiding light for a
> > backport?
> >
> >
> 
> There are 2 example scenarios in the changelog that misbehave without
> this fix, cases where the protection of a memcg that is the target of
> reclaim is not ignored as it should be.

Yes.  I found them quite unclear.  How would someone who is
experiencing a particualr runtime issue be able to recognize whether
this patch might address that issue?