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From: Andi Kleen <ak@suse.de>
To: Nick Piggin <nickpiggin@yahoo.com.au>
Subject: Re: i386 and PAE: pud_present()
Date: Fri, 28 Apr 2006 10:27:21 +0200
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Cc: Magnus Damm <magnus.damm@gmail.com>,
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       Linux Memory Management <linux-mm@kvack.org>
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On Friday 28 April 2006 09:54, Nick Piggin wrote:
> Magnus Damm wrote:
> > Hi guys,
> > 
> > In file include/asm-i386/pgtable-3level.h:
> > 
> > On i386 with PAE enabled, shouldn't pud_present() return (pud_val(pud)
> > & _PAGE_PRESENT) instead of constant 1?
> > 
> > Today pud_present() returns constant 1 regardless of PAE or not. This
> > looks wrong to me, but maybe I'm misunderstanding how to fold the page
> > tables... =)
> 
> Take a look a little further down the page for the comment.
> 
> In i386 + PAE, pud is always present.

I think his problem is that the PGD is always present too (in pgtables-nopud.h)
Indeed looks strange.

-Andi