From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Galbraith <efault@gmx.de>
Subject: Re: [PATCH PREEMPT RT] rt-mutex: fix deadlock in device mapper
Date: Tue, 21 Nov 2017 18:33:39 +0100
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Cc: Thomas Gleixner <tglx@linutronix.de>,
        Sebastian Siewior <bigeasy@linutronix.de>,
        linux-kernel@vger.kernel.org, Ingo Molnar <mingo@redhat.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        linux-rt-users@vger.kernel.org
To: Mikulas Patocka <mpatocka@redhat.com>
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On Tue, 2017-11-21 at 11:11 -0500, Mikulas Patocka wrote:
> 
> So, drop the spinlock unplugging and leave only mutex unplugging, 
> reproduce the deadlock and send the stacktraces.

Nah, I reproduced it five years ago.  Is any of that relevant today?
 Damned if I know.  Your report was the first I've noticed since.

	-Mike