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Message-ID: <1453255746.3122.44.camel@linux.intel.com>
Subject: Re: tty: deadlock between n_tracerouter_receivebuf and
 flush_to_ldisc
From: J Freyensee <james_p_freyensee@linux.intel.com>
To: One Thousand Gnomes <gnomes@lxorguk.ukuu.org.uk>,
        Dmitry Vyukov <dvyukov@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>, LKML <linux-kernel@vger.kernel.org>,
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        Kostya Serebryany <kcc@google.com>,
        Alexander Potapenko <glider@google.com>,
        Sasha Levin <sasha.levin@oracle.com>,
        Eric Dumazet <edumazet@google.com>
Date: Tue, 19 Jan 2016 18:09:06 -0800
In-Reply-To: <20160115163300.063c224d@lxorguk.ukuu.org.uk>
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On Fri, 2016-01-15 at 16:33 +0000, One Thousand Gnomes wrote:
> On Fri, 15 Jan 2016 08:51:39 +0100
> Dmitry Vyukov <dvyukov@google.com> wrote:
> 
> > On Wed, Dec 30, 2015 at 11:44 AM, Dmitry Vyukov <dvyukov@google.com
> > > wrote:
> > > Hello,
> > > 
> > > I've got the following lock order inversion report on
> > > 8513342170278468bac126640a5d2d12ffbff106 (Dec 28). Unfortunately
> > > I
> > > failed to find a reproducer for it.
> > 
> > Ping. This is the most frequent failure during my testing now. J
> > Freyensee, you seem to wrote drivers/tty/n_tracerouter.c. Please
> > take
> > a look. Thanks.

I did look at the report but didn't see how n_tracerouter could be
causing the issue.  I apologize for not responding, and I thank you so
very much for providing the thorough explanation, Alan.

Jay

> 
> Alan