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	Thu, 19 May 2011 07:50:36 +1000 (EST)
Date: Wed, 18 May 2011 16:50:25 -0500
From: Scott Wood <scottwood@freescale.com>
To: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH 5/7] powerpc/mm: 64-bit: don't handle non-standard page
	sizes
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Cc: linuxppc-dev@lists.ozlabs.org, David Gibson <dwg@au1.ibm.com>
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On Thu, 19 May 2011 07:36:04 +1000
Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:

> On Wed, 2011-05-18 at 16:05 -0500, Scott Wood wrote:
> > I don't see where any non-standard page size will be set in the
> > kernel page tables, so don't waste time checking for it.  It wouldn't
> > work with TLB0 on an FSL MMU anyway, so if there's something I missed
> > (or which is out-of-tree), it's relying on implementation-specific
> > behavior.  If there's an out-of-tree need for occasional 4K mappings
> > with CONFIG_PPC_64K_PAGES, perhaps this check could only be done when
> > that is defined.
> > 
> > Signed-off-by: Scott Wood <scottwood@freescale.com>
> > ---
> 
> Do you use that in the hugetlbfs code ? Can you publish that code ? It's
> long overdue...

hugetlbfs entries don't get loaded by this code.  It branches to a slow
path based on seeing a positive value in a pgd/pud/pmd entry.

-Scott