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Date: Wed, 4 Apr 2012 16:14:21 -0700 (PDT)
From: David Rientjes <rientjes@google.com>
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To: Tejun Heo <tj@kernel.org>
cc: Mike Galbraith <mgalbraith@suse.de>,
        Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Li Zefan <lizf@cn.fujitsu.com>, Paul Menage <paul@paulmenage.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [patch] cgroups: disallow attaching kthreadd
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On Wed, 4 Apr 2012, Tejun Heo wrote:

> I don't see much problem with the proposed solution and am gonna take
> it unless there are pretty good reasons not to.
> 

The only cgroup that cannot allow kthreadd is cpusets and that's 
illustrated by Mike's changelog.  Restricting it for all cgroups is 
completely unnecessary, as I've already said, and is the entire reason we 
have ->can_attach() functions for each cgroup.

Also see Paul Menage's suggestion for only isolating this fix to cpusets 
as well at 
http://lkml.indiana.edu/hypermail/linux/kernel/1110.2/01280.html.

Thanks.