Re: [PATCH] mm: fix page_mkclean_one

[David Miller <davem@davemloft.net>]

From: "Chen, Kenneth W" <kenneth.w.chen@intel.com>
Date: Wed, 27 Dec 2006 22:10:52 -0800

> Chen, Kenneth wrote on Wednesday, December 27, 2006 9:55 PM
> > Linus Torvalds wrote on Wednesday, December 27, 2006 7:05 PM
> > > On Wed, 27 Dec 2006, David Miller wrote:
> > > > > 
> > > > > I still don't see _why_, though. But maybe smarter people than me can see 
> > > > > it..
> > > > 
> > > > FWIW this program definitely triggers the bug for me.
> > > 
> > > Ok, now that I have something simple to do repeatable stuff with, I can 
> > > say what the pattern is.. It's not all that surprising, but it's still 
> > > worth just stating for the record.
> > 
> > 
> > Running the test code, git bisect points its finger at this commit. Reverting
> > this commit on top of 2.6.20-rc2 doesn't trigger the bug from the test code.
> > 
> > edc79b2a46ed854595e40edcf3f8b37f9f14aa3f is first bad commit
> > commit edc79b2a46ed854595e40edcf3f8b37f9f14aa3f
> > Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
> > Date:   Mon Sep 25 23:30:58 2006 -0700
> > 
> >     [PATCH] mm: balance dirty pages
> > 
> >     Now that we can detect writers of shared mappings, throttle them.  Avoids OOM
> >     by surprise.
> 
> 
> Oh, never mind :-(  I just didn't create enough write out pressure when
> test this. I just saw bug got triggered on a kernel I previously thought
> was OK.

Besides, I'm pretty sure that from the Debian bug entry it's been
established that the dirty-page tracking changes from a few releases
ago introduced this problem.