Re: [WARNING] kernel/workqueue.c:2041 process_one_work (when cpu goes offline)

From: Tejun Heo
Date: Tue Apr 18 2017 - 04:12:28 EST


Hello,

On Tue, Apr 11, 2017 at 09:08:37AM +0900, Tejun Heo wrote:
> On Wed, Apr 05, 2017 at 03:16:28PM -0400, Steven Rostedt wrote:
> > My tests have started to recently trigger this warning quite often,
> > which causes my tests to fail. The test that triggers this is running
> > the mmiotracer which forces all but one CPU offline.

So, the rescuer handling seems fine and nothing really changed from
workqueue side. Any chance cpuset is involved? If so, there was a
recent race condition fix 77f88796cee8 ("cgroup, kthread: close race
window where new kthreads can be migrated to non-root cgroups"). If
that's not it, it'd be great if you can explain the test case so that
I can repro the problem.

Thanks.

--
tejun