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Date: Fri, 7 Aug 2026 13:22:41 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Ridong <ridong.chen@linux.dev>
Cc: Johannes Weiner <hannes@cmpxchg.org>, Michal Hocko <mhocko@kernel.org>,
 Roman Gushchin <roman.gushchin@linux.dev>, Shakeel Butt
 <shakeel.butt@linux.dev>, Muchun Song <muchun.song@linux.dev>, Tejun Heo
 <tj@kernel.org>, Michal =?ISO-8859-1?Q?Koutn=FD?= <mkoutny@suse.com>,
 cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org,
 cui.tao@linux.dev, Ridong Chen <chenridong@xiaomi.com>
Subject: Re: [PATCH v2 0/2] mm, memcg: fix memory.peak reset clobbering
 other fds' watermark
Message-Id: <20260807132241.147c758d2904e00daf28ba4e@linux-foundation.org>
In-Reply-To: <20260807090000.1532495-1-ridong.chen@linux.dev>
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On Fri,  7 Aug 2026 16:59:58 +0800 Ridong <ridong.chen@linux.dev> wrote:

> Two fixes for the per-fd memory.peak / memory.swap.peak handlers added in
> c6f53ed8f213. Each open fd reads back max(its own value, the shared
> local_watermark), and both bugs live in that scheme.

Thanks.

We're missing the preferred description of the worst-case
userspace-visible effects of the bug.  It appears they're quite minor
so I'll assume this series is a post-7.2 thing.

Sashiko might have found a similar race on the writer side:
	https://sashiko.dev/#/patchset/20260807090000.1532495-1-ridong.chen@linux.dev