From: Stephen Hemminger <stephen@networkplumber.org>
To: Mike Galbraith <efault@gmx.de>
Cc: netdev <netdev@vger.kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>
Subject: Re: net/sched: latent livelock in dev_deactivate_many() due to yield() usage
Date: Wed, 5 Apr 2017 17:31:05 -0700 [thread overview]
Message-ID: <20170405173105.7f41d7fc@plumbers-lap.home.lan> (raw)
In-Reply-To: <1491107321.13631.33.camel@gmx.de>
On Sun, 02 Apr 2017 06:28:41 +0200
Mike Galbraith <efault@gmx.de> wrote:
> Livelock can be triggered by setting kworkers to SCHED_FIFO, then
> suspend/resume.. you come back from sleepy-land with a spinning
> kworker. For whatever reason, I can only do that with an enterprise
> like config, my standard config refuses to play, but no matter, it's
> "Typical broken usage".
>
> (yield() should be rendered dead)
The kernel is not normally built to have kworkers run at SCHED_FIFO.
The user has do some action to alter the process priorities.
I classify this as user error. We don't support killing kworker threads
either.
next prev parent reply other threads:[~2017-04-06 0:31 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-04-02 4:28 net/sched: latent livelock in dev_deactivate_many() due to yield() usage Mike Galbraith
2017-04-04 22:39 ` Cong Wang
2017-04-05 3:20 ` Mike Galbraith
2017-04-05 5:25 ` Cong Wang
2017-04-05 6:12 ` Mike Galbraith
2017-04-05 23:55 ` Cong Wang
2017-04-06 1:08 ` Mike Galbraith
2017-04-06 10:26 ` Peter Zijlstra
2017-04-06 0:31 ` Stephen Hemminger [this message]
2017-04-06 1:28 ` Mike Galbraith
2017-04-06 10:28 ` Peter Zijlstra
2017-04-06 11:08 ` Peter Zijlstra
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