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Date: Wed, 28 Jan 2015 12:53:32 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: Zefan Li <lizefan@huawei.com>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>,
        LKML <linux-kernel@vger.kernel.org>, Ingo Molnar <mingo@kernel.org>
Subject: Re: [patch] cpuset: fix crash when adding CPUs to an empty set
Message-ID: <20150128115332.GD23038@twins.programming.kicks-ass.net>
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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?