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Date: Fri, 10 Jun 2011 15:35:50 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Eric Paris <eparis@redhat.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>,
        John McCutchan <john@johnmccutchan.com>, Robert Love <rlove@rlove.org>,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: Race inotify_rm_watch vs umount
Message-ID: <20110610143550.GZ11521@ZenIV.linux.org.uk>
References: <87r572nd9k.fsf@devron.myhome.or.jp>
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On Fri, Jun 10, 2011 at 09:46:05AM -0400, Eric Paris wrote:
> On Fri, 2011-06-10 at 20:20 +0900, OGAWA Hirofumi wrote:
> > Hi,
> > 
> > I'm looking the race inotify_rm_watch() vs umount(). This race become the
> > cause of Oops. You can see the oops at
> > 
> > https://bugzilla.kernel.org/show_bug.cgi?id=22602
> > 
> > So, what race?
> 
> Ok, I see what you are saying, I'll see what I can do.  I'm a little
> scared to call something like iput() under a lock though.  I might be
> able to make the bigest lock a mutex and fix this....

Which lock would that be?  I don't see any good candidates in there...