From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
Subject: Re: [PATCH v5 3/3] cgroups: make procs file writable
Date: Fri, 24 Dec 2010 03:53:31 -0800
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To: Ben Blum <bblum-OM76b2Iv3yLQjUSlxSEPGw@public.gmane.org>
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On Fri, 24 Dec 2010 06:45:00 -0500 Ben Blum <bblum-OM76b2Iv3yLQjUSlxSEPGw@public.gmane.org> wrote:

> > kmalloc() is allowed while holding a spinlock and NODEMASK_ALLOC() takes a 
> > gfp_flags argument for that reason.
> 
> Ah, it's only with GFP_KERNEL and friends. So changing the uses in
> cpuset_can_attach to GFP_ATOMIC would solve this concern, then?

It would introduce an additional concern.  GFP_ATOMIC is bad, for a
number of reasons.  The main one of which is that it is vastly less
reliable than GFP_KERNEL.  And making the cpuset code less reliable
is a regression, no?

Please try to find a better solution.