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Date: Fri, 29 Dec 2006 10:27:42 -0500
From: Theodore Tso <tytso@mit.edu>
To: Linus Torvalds <torvalds@osdl.org>
Cc: Segher Boessenkool <segher@kernel.crashing.org>,
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Subject: Re: Ok, explained.. (was Re: [PATCH] mm: fix page_mkclean_one)
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On Fri, Dec 29, 2006 at 12:58:12AM -0800, Linus Torvalds wrote:
> Because what "__set_page_dirty_buffers()" does is that AT THE TIME THE 
> "set_page_dirty()" IS CALLED, it will mark all the buffers on that page as 
> dirty. That may _sound_ like what we want, but it really isn't. Because by 
> the time "writepage()" is actually called (which can be MUCH MUCH later), 
> some internal filesystem activity may actually have cleaned one or more of 
> those buffers in the meantime, and now we call "writepage()" (which really 
> wants to write them _all_), and it will write only part of them, or none 
> at all.

I'm confused.  Does this mean that if "fs blocksize"=="VM pagesize"
this bug can't trigger?  But I thought at least one of people
reporting corruption was using a filesystem with a 4k block size on an
i386?

						- Ted