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Date: Tue, 26 Apr 2005 04:50:39 -0700
From: Andrew Morton <akpm@osdl.org>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: andrea@suse.de, linux-kernel@vger.kernel.org
Subject: Re: [patch] __block_write_full_page bug
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Nick Piggin <nickpiggin@yahoo.com.au> wrote:
>
>  When running
>  	fsstress -v -d $DIR/tmp -n 1000 -p 1000 -l 2
>  on an ext2 filesystem with 1024 byte block size, on SMP i386 with 4096 byte
>  page size over loopback to an image file on a tmpfs filesystem, I would
>  very quickly hit
>  	BUG_ON(!buffer_async_write(bh));
>  in fs/buffer.c:end_buffer_async_write
> 
>  It seems that more than one request would be submitted for a given bh
>  at a time. __block_write_full_page looks like the culprit - with the
>  following patch things are very stable.

What's the bug?  I don't see it.

Was an ENOSPC involved?

Those tests for buffer_async_write(bh) are redundant now, aren't they?