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Date: Tue, 29 May 2007 15:14:42 +1000
From: Nick Piggin <nickpiggin@yahoo.com.au>
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To: "Eric W. Biederman" <ebiederm@xmission.com>
CC: Andrew Morton <akpm@linux-foundation.org>,
       Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [PATCH 1/3] Preserve the dirty bit in init_page_buffers
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Eric W. Biederman wrote:
> Nick Piggin <nickpiggin@yahoo.com.au> writes:

>> However we
>>could still set_page_dirty of a block device page without buffers
>>via an mmap.
> 
> 
> After the page is made dirty via mmap we have:
> sys_write -> ... -> block_prepare_write -> ... -> create_empty_buffers.

Yep, that's what I mean.


> I suspect that is a pretty rare case but it does indeed seem to exist
> as a problem.

I think so too. But either we have some misunderstanding of the
codepaths involved, or the author of the comments there didn't
consider this case, so...

-- 
SUSE Labs, Novell Inc.