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Sender: Tejun Heo <htejun@gmail.com>
Date:   Tue, 14 Sep 2021 06:23:32 -1000
From:   Tejun Heo <tj@kernel.org>
To:     Zhang Qiao <zhangqiao22@huawei.com>
Cc:     mingo@redhat.com, peterz@infradead.org,
        linux-kernel@vger.kernel.org, juri.lelli@redhat.com,
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        bristot@redhat.com
Subject: Re: [PATCH v2] kernel/sched: Fix sched_fork() access an invalid
 sched_task_group
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On Tue, Sep 14, 2021 at 04:20:02PM +0800, Zhang Qiao wrote:
> Perhaps we can fix this bug at sched_post_fork(), which is executed between cgroup_can_fork()
> and cgroup_post_fork(). Relocate the fectching of task_group and access it at sched_post_fork().

Can't we just add a can_fork callback in cpu_cgrp_subsys?

-- 
tejun