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Date: Wed, 21 Feb 2024 11:22:23 +0100
From: Michal Hocko <mhocko@suse.com>
To: Gong Ruiqi <gongruiqi1@huawei.com>
Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org,
	Johannes Weiner <hannes@cmpxchg.org>,
	Roman Gushchin <roman.gushchin@linux.dev>,
	Shakeel Butt <shakeelb@google.com>,
	Muchun Song <muchun.song@linux.dev>, cgroups@vger.kernel.org,
	linux-mm@kvack.org, Wang Weiyang <wangweiyang2@huawei.com>,
	Xiu Jianfeng <xiujianfeng@huawei.com>
Subject: Re: [PATCH stable] memcg: add refcnt for pcpu stock to avoid UAF
 problem in drain_all_stock()
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On Wed 21-02-24 11:08:02, Michal Hocko wrote:
[...]
> You are right. Thanks! IRQ disabling is there in one form or the other
> since db2ba40c277d ("mm: memcontrol: make per-cpu charge cache IRQ-safe
> for socket accounting") so 4.8+ is safe. Backports to older kernels
> would nee to pull this one as well.

Scratch that. Prior to db2ba40c277d, we used to disable preemption via
{get,put}_cpu_var and that should achive the same result.
-- 
Michal Hocko
SUSE Labs