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Date: Mon, 16 Nov 2015 13:52:21 -0500
From: Tejun Heo <tj@kernel.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Ingo Molnar <mingo@kernel.org>, Peter Zijlstra <peterz@infradead.org>,
        Milos Vyletel <milos@redhat.com>, Prarit Bhargava <prarit@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/8] stop_machine: cpu_stopper_thread() must check done
 != NULL
Message-ID: <20151116185221.GK18894@mtj.duckdns.org>
References: <20151115193254.GA8225@redhat.com>
 <20151115193311.GA8242@redhat.com>
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On Sun, Nov 15, 2015 at 08:33:11PM +0100, Oleg Nesterov wrote:
> stop_one_cpu_nowait(fn) will crash the kernel if the callback returns
> nonzero, work->done == NULL in this case.
> 
> This needs more cleanups, cpu_stop_signal_done() is called right after
> we check done != NULL and it does the same check.
> 
> Signed-off-by: Oleg Nesterov <oleg@redhat.com>

Acked-by: Tejun Heo <tj@kernel.org>

cc stable?

Thanks.

-- 
tejun