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Date: Thu, 15 May 2014 10:07:53 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: "Carlos O'Donell" <carlos@redhat.com>
Cc: Darren Hart <dvhart@linux.intel.com>, Thomas Gleixner <tglx@linutronix.de>,
        LKML <linux-kernel@vger.kernel.org>, Dave Jones <davej@redhat.com>,
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        Jakub Jelinek <jakub@redhat.com>,
        Michael Kerrisk <mtk.manpages@gmail.com>,
        Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Subject: Re: [patch 0/3] futex/rtmutex: Fix issues exposed by trinity
Message-ID: <20140515080753.GB30445@twins.programming.kicks-ass.net>
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On Wed, May 14, 2014 at 05:17:35PM -0400, Carlos O'Donell wrote:
> > No, its perfectly fine to have a lock sequence abort with -EDEADLK.
> > Userspace should release its locks and re-attempt.
>=20
> I agree. If I can prove that it's actually a deadlock, and
> that unlock/relock will work to fix it, then we can arrange for glibc
> to return EDEADLK.

The only reason the kernel would return EDEADLK is because its walked
the lock graph and determined its well, a deadlock.

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