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Date: Wed, 29 Mar 2006 09:27:47 +0100
From: Al Viro <viro@ftp.linux.org.uk>
To: Jens Axboe <axboe@suse.de>
Cc: Mark Lord <lkml@rtr.ca>, Linux Kernel <linux-kernel@vger.kernel.org>
Subject: Re: 2.6.16-git4: kernel BUG at block/ll_rw_blk.c:3497
Message-ID: <20060329082747.GV27946@ftp.linux.org.uk>
References: <44288882.4020809@rtr.ca> <20060329081642.GU8186@suse.de>
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On Wed, Mar 29, 2006 at 10:16:43AM +0200, Jens Axboe wrote:
> triggering. What sort of testing were you running, exactly?
> 
> Al, any ideas?

I really wonder why it's the call from do_exit() that triggers it.
The thing is, we get off-by-exactly-one here and all previous callers
of that puppy would be elsewhere (cfq, mostly).

IOW, we get exactly one extra call of put_io_context() _and_ have it
happen before do_exit() (i.e. from normal IO paths).  Interesting...

Is there any way to reproduce it without too much PITA?