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Date: Tue, 27 May 2014 16:26:37 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "Jason J. Herne" <jjherne@linux.vnet.ibm.com>
Cc: Lai Jiangshan <laijs@cn.fujitsu.com>, Sasha Levin <sasha.levin@oracle.com>,
        Tejun Heo <tj@kernel.org>, LKML <linux-kernel@vger.kernel.org>,
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        Thomas Gleixner <tglx@linutronix.de>,
        Steven Rostedt <rostedt@goodmis.org>
Subject: Re: workqueue: WARN at at kernel/workqueue.c:2176
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On Tue, May 27, 2014 at 10:18:31AM -0400, Jason J. Herne wrote:
> On 05/16/2014 12:29 PM, Peter Zijlstra wrote:
> >On Sat, May 17, 2014 at 12:18:06AM +0800, Lai Jiangshan wrote:
> >>so the scheduler/set_cpus_allowed_ptr()/cpu_active_mask should be the first
> >>place to fix.
> >
> >I'm not arguing about that, not to mention that this is userspace
> >exposed and nobody protects that.
> >
> >But I was expecting kernel stuff that calls it on hotplug to be
> >serialized thusly, but apparently not so.
> >
> 
> Was a final patch posted for this issue? The discussion made it sound like
> there were still a few things to figure out before we could resolve this
> bug. I can recreate this as needed and I'm happy to test any patches.


https://git.kernel.org/cgit/linux/kernel/git/tip/tip.git/commit/?h=sched/urgent&id=6acbfb96976fc3350e30d964acb1dbbdf876d55e

which should make its way to Linus soonish I suppose.