From: Tejun Heo <tj@kernel.org>
To: Jan Kara <jack@suse.cz>
Cc: "Michal Koutný" <mkoutny@suse.com>,
"Paolo Valente" <paolo.valente@linaro.org>,
linux-block@vger.kernel.org, fvogdt@suse.de,
cgroups@vger.kernel.org
Subject: Re: Use after free with BFQ and cgroups
Date: Tue, 30 Nov 2021 06:22:13 -1000 [thread overview]
Message-ID: <YaZPtZcdMKwhzzy/@slm.duckdns.org> (raw)
In-Reply-To: <20211130115010.GF7174@quack2.suse.cz>
Hello,
On Tue, Nov 30, 2021 at 12:50:10PM +0100, Jan Kara wrote:
> The problem is bfq_queue associated with a task effectively holds a
> reference to the potentially dead cgroup and the reference can stay there
> until the task (that itself got reparented to the root cgroup) exits. So I
> think we need to reparent these bfq_queue structures as well to avoid
> holding cgroup in zombie state excessively long.
Ah, I see. Yeah, that's not great. Agree that it'd be better to reparent
(probably just punt to the root cgroup).
Thanks.
--
tejun
prev parent reply other threads:[~2021-11-30 16:22 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-11-25 17:28 Use after free with BFQ and cgroups Jan Kara
2021-11-26 14:47 ` Michal Koutný
2021-11-29 17:11 ` Jan Kara
2021-12-09 2:23 ` yukuai (C)
2021-12-09 15:33 ` Paolo Valente
2021-12-13 17:33 ` Jan Kara
2021-12-14 1:24 ` yukuai (C)
2021-12-20 18:38 ` Jan Kara
2021-12-22 15:21 ` Jan Kara
2021-12-23 1:02 ` yukuai (C)
2021-12-23 17:13 ` Jan Kara
2021-11-29 17:12 ` Tejun Heo
2021-11-30 11:50 ` Jan Kara
2021-11-30 16:22 ` Tejun Heo [this message]
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