From mboxrd@z Thu Jan  1 00:00:00 1970
From: Thomas Gleixner <tglx@linutronix.de>
Subject: Re: [PATCH RT] sched: Prevent task state corruption by spurious lock
 wakeup
Date: Tue, 6 Jun 2017 14:16:38 +0200 (CEST)
Message-ID: <alpine.DEB.2.20.1706061412290.1885@nanos>
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        Peter Zijlstra <peterz@infradead.org>,
        Mathias Koehrer <mathias.koehrer@etas.com>,
        David Hauck <davidh@netacquire.com>
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On Sat, 3 Jun 2017, Thomas Gleixner wrote:
> If the to be woken task has state TASK_TRACED then the wakeup state check
> should not match. But for some stupid reason wake_up_lock_sleeper() should
> not use TASK_ALL. The lock sleepers are in state UNINTERRUPTIBLE, so the
> wake state should be UNINTERRUPTIBLE as well.
> 
> The extra check in try_to_wake_up() should stay though as it prevents
> spurious wake ups in general.

Further experimentation shows that it's not worth it. I'll send a V2 of
that patch with the proper fix.

Thanks,

	tglx