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Date: Tue, 14 Jun 2016 17:39:48 +0100
From: Juri Lelli <juri.lelli@arm.com>
To: xlpang@redhat.com
Cc: Peter Zijlstra <peterz@infradead.org>, mingo@kernel.org,
        tglx@linutronix.de, rostedt@goodmis.org, linux-kernel@vger.kernel.org,
        mathieu.desnoyers@efficios.com, jdesfossez@efficios.com,
        bristot@redhat.com, Ingo Molnar <mingo@redhat.com>
Subject: Re: [RFC][PATCH 2/8] sched/rtmutex/deadline: Fix a PI crash for
 deadline tasks
Message-ID: <20160614163948.GN5981@e106622-lin>
References: <20160607195635.710022345@infradead.org>
 <20160607200215.719626477@infradead.org>
 <20160614102109.GF5981@e106622-lin>
 <575FFE58.1090102@redhat.com>
 <20160614130707.GJ5981@e106622-lin>
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On 14/06/16 14:07, Juri Lelli wrote:
> On 14/06/16 20:53, Xunlei Pang wrote:
> > On 2016/06/14 at 18:21, Juri Lelli wrote:
> > > Hi,
> > >
> > > On 07/06/16 21:56, Peter Zijlstra wrote:
> > >> From: Xunlei Pang <xlpang@redhat.com>
> > >>

[...]

> > > The idea of this fix makes sense to me. But, I would like to be able to
> > > see the BUG and test the fix. What I have is a test in which I create N
> > > DEADLINE workers that share a PI mutex. They get migrated around and
> > > seem to stress PI code. But I couldn't hit the BUG yet. Maybe I let it
> > > run for some more time.
> > 
> > You can use this reproducer attached(gcc crash_deadline_pi.c -lpthread -lrt ).
> > Start multiple instances, then it will hit the bug very soon.
> > 
> 
> Great, thanks! I'll use it.
> 

OK. I could reproduce and also test that I can't see the BUG anymore
with the fix.