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Date: Fri, 8 Jan 2016 11:26:04 -0500
From: "J. Bruce Fields" <bfields@fieldses.org>
To: Jeff Layton <jlayton@poochiereds.net>
Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        Dmitry Vyukov <dvyukov@google.com>,
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        Alexander Potapenko <glider@google.com>,
        Sasha Levin <sasha.levin@oracle.com>,
        Eric Dumazet <edumazet@google.com>
Subject: Re: [PATCH v2 1/6] locks: fix unlock when fcntl_setlk races with a
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Message-ID: <20160108162604.GD3989@fieldses.org>
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On Fri, Jan 08, 2016 at 11:22:04AM -0500, J. Bruce Fields wrote:
> On Fri, Jan 08, 2016 at 11:21:01AM -0500, J. Bruce Fields wrote:
> > Yeah.  I almost think an OK iterim solution would be just to document
> > the race in the appropriate man page and tell people that if they really
> > want to use posix locks in an application with lots of threads sharing
> > file descriptors then they should consider OFD locks.
> 
> (Especially if this race has always existed.)

Oh but note I'm only talking about this additional race that you've
identified.

I agree that the problem addressed by these patches need fixing, and
gave them a quick read and they look OK to me--feel free to add my ACK.

--b.