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Date:   Tue, 30 Apr 2019 16:53:43 +0200
From:   Oleg Nesterov <oleg@redhat.com>
To:     Peter Zijlstra <peterz@infradead.org>
Cc:     Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
        linux-rt-users <linux-rt-users@vger.kernel.org>,
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        Clark Williams <williams@redhat.com>,
        Juri Lelli <juri.lelli@redhat.com>, jack@suse.com
Subject: Re: [RT WARNING] DEBUG_LOCKS_WARN_ON(rt_mutex_owner(lock) !=
 current) with fsfreeze (4.19.25-rt16)
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On 04/30, Peter Zijlstra wrote:
>
> On Tue, Apr 30, 2019 at 04:42:53PM +0200, Oleg Nesterov wrote:
> > I have cloned linux-rt-devel.git
> >
> > If I understand correctly, in rt rw_semaphore is actually defined in rwsem_rt.h
> > so percpu_rwsem_acquire() should probably do
> >
> > 	sem->rw_sem.rtmutex.owner = current;
>
> That'll screw the PI chain (if there is one), right?

Yes, I have already realized this can't work after I glanced at this code, thanks.

Oleg.