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Date: Mon, 18 Feb 2013 09:32:18 -0800
From: Tejun Heo <tj@kernel.org>
To: Li Zefan <lizefan@huawei.com>
Cc: "Kirill A. Shutemov" <kirill@shutemov.name>,
        LKML <linux-kernel@vger.kernel.org>, Cgroups <cgroups@vger.kernel.org>
Subject: Re: [PATCH] cgroup: fail if monitored file and event_control are in
 different cgroup
Message-ID: <20130218173218.GH17414@htj.dyndns.org>
References: <5121C68F.1000309@huawei.com>
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On Mon, Feb 18, 2013 at 02:13:35PM +0800, Li Zefan wrote:
> If we pass fd of memory.usage_in_bytes of cgroup A to cgroup.event_control
> of cgroup B, then we won't get memory usage notification from A but B!
> 
> What's worse, if A and B are in different mount hierarchy, we'll end up
> accessing NULL pointer!
> 
> Disallow this kind of invalid usage.
> 
> Signed-off-by: Li Zefan <lizefan@huawei.com>

Applied to cgroup/for-3.9.

Thanks.

-- 
tejun