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Date: Sun, 18 Dec 2011 02:47:30 +0300
From: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
To: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        Jens Axboe <axboe@kernel.dk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Kay Sievers <kay.sievers@vrfy.org>, Namhyung Kim <namhyung@gmail.com>,
        Lukas Czerner <lczerner@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] loop: fput() called in loop_clr_fd() may cause bd_mutex
 recursive locking
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On (12/17/11 23:38), Al Viro wrote:
> On Sun, Dec 18, 2011 at 02:20:53AM +0300, Sergey Senozhatsky wrote:
> 
> > > IOW, we have to prevent such setups anyway and not just because of
> > > problems on close() - they would be deadly on read() and write()...
> > > 
> > 
> > Preventing recursion in the first place? For example, in lo_open()?
> 
> Uh?  No, in loop_set_fd(), where we decide what loop devices will be
> backed by what - the code I quoted to you upthread.
> 

Oops, sorry. Long day at work . Need to sleep.

	Sergey