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Subject: Re: [PATCH] powerpc/8xx: fix regression introduced by cache
	coherency rewrite
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Scott Wood <scottwood@freescale.com>
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Date: Tue, 06 Oct 2009 07:29:15 +1100
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On Mon, 2009-10-05 at 14:28 -0500, Scott Wood wrote:
> Yes, it hits ptep_set_access_flags() and adding _tlbil_va there helps (I
> didn't put it in the filter function, because that doesn't take address as a
> parameter).  I'd misread your suggestion as referring to the various changes
> to set_pte_filter() that were posted.
> 
> As for unconditionally invalidating in set_pte_filter(), that doesn't boot
> for me unless I check for kernel addresses -- I guess we populate page
> tables that overlap the pinned large page region? 

Good point. I think we do on 8xx. Does doing it in set_pte_filter()
(with the kernel check) makes any difference ? faster ? slower ? no
visible change ?

Cheers,
Ben.