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Subject: Re: x86_64: potential critical issue with quicklists and page
	table pages
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Christoph Lameter <clameter@sgi.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Date: Tue, 25 Sep 2007 10:09:28 +1000
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On Mon, 2007-09-24 at 14:42 -0700, Christoph Lameter wrote:
> On Tue, 25 Sep 2007, Benjamin Herrenschmidt wrote:
> 
> > I'd suggest just reverting the patch for now (well, I see from the
> > commit list that you did just that) and I'll try to come up with
> > something better.
> 
> That would be great. Note that the reversal of the x86_64 quicklist 
> support patch does not address the issue that is (as pointed out by 
> Siddha) in core code and not in x86_64 arch dode. The fix that I posted 
> fixes the core issue.
> 
> > Christoph, I'd be happy if you didn't start butchering mmu_gather just
> > right now since I'm doing just that and it will collide all over the
> > place :-) Or if you want something specific done, please throw
> > ideas/patches at me and I'll integrate that in my serie.
> 
> Any "butchering" was done for 2.6.22. 2.6.23 only added arch support for 
> x86_64 since Andi forgot to merge it for .22. I'd be glad if you could 
> look into this and make quicklists interoperate nicely withh mmu gather.

I'll try, I'll let you know. Give me a few days to finish catching up
with backlog of things before i get back to it though.

Cheers,
Ben.