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Message-ID: <1422446595.5716.34.camel@marge.simpson.net>
Subject: Re: [patch] cpuset: fix crash when adding CPUs to an empty set
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Zefan Li <lizefan@huawei.com>, LKML <linux-kernel@vger.kernel.org>,
        Ingo Molnar <mingo@kernel.org>
Date: Wed, 28 Jan 2015 13:03:15 +0100
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On Wed, 2015-01-28 at 12:53 +0100, Peter Zijlstra wrote: 
> On Wed, Jan 28, 2015 at 12:24:52PM +0800, Zefan Li wrote:
> > > sched: Fix crash if cpuset_cpumask_can_shrink() is passed an empty cpumask
> > > 
> > > While creating an exclusive cpuset, we passed cpuset_cpumask_can_shrink()
> > > an empty cpumask (cur), and dl_bw_of(cpumask_any(cur)) made boom with it.
> > > 
> 
> Is this the case where a new cpuset doesn't yet have CPUs assigned?

Yes.

-Mike