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Date: Thu, 17 Apr 2008 13:27:07 +0800
From: Li Zefan <lizf@cn.fujitsu.com>
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To: Paul Menage <menage@google.com>
CC: Andrew Morton <akpm@linux-foundation.org>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       LKML <linux-kernel@vger.kernel.org>,
       Linux Containers <containers@lists.linux-foundation.org>,
       Balbir Singh <balbir@linux.vnet.ibm.com>,
       KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>,
       Paul Jackson <pj@sgi.com>
Subject: Re: [PATCH] cgroup: fix a race condition in manipulating tsk->cg_list
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Paul Menage wrote:
> On Wed, Apr 16, 2008 at 10:16 PM, Andrew Morton
> <akpm@linux-foundation.org> wrote:
>>  > > Maybe it would be better to not do a cgroup_exit() until we're
>>  > > unhashed, so that cgroup_enable_task_cg_list() can't find the exiting
>>  > > task?
>>
>>  So we won't be doing what Paul suggested?
>>
> 
> It's not as high a priority as Li's bug fix (which may be a good
> candidate for 2.6.25.1) but for the future I think I'll implement this
> distinguished css_set pointer for tasks that have finished
> cgroup_exit(), since I think it will make the similar synchronization
> in attach_task() cleaner, as well as cgroup_enable_task_cg_list().
> 

Yes, this approach sounds good to me. :)

> Paul
>