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Subject: Re: [PATCH] sched, cgroup: Use exit hook to avoid use-after-free
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From: Mike Galbraith <efault@gmx.de>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Miklos Vajna <vmiklos@frugalware.org>,
        shenghui <crosslonelyover@gmail.com>, kernel-janitors@vger.kernel.org,
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On Fri, 2010-12-24 at 16:59 +0100, Peter Zijlstra wrote:

> So cgroup moves a task without calling cgroup_subsys::attach() which is
> odd, but it does have an ::exit method, sadly it calls that _before_
> re-assigning the task, which means we have to jump through some hoops.

Could you do the move in cgroup_exit() in the CONFIG_PREEMPT case?

	-Mike


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