From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751068AbWD3Ixk (ORCPT ); Sun, 30 Apr 2006 04:53:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751070AbWD3Ixk (ORCPT ); Sun, 30 Apr 2006 04:53:40 -0400 Received: from mx2.suse.de ([195.135.220.15]:33461 "EHLO mx2.suse.de") by vger.kernel.org with ESMTP id S1751068AbWD3Ixk (ORCPT ); Sun, 30 Apr 2006 04:53:40 -0400 From: Andi Kleen To: Dave McCracken Subject: Re: i386 and PAE: pud_present() Date: Sun, 30 Apr 2006 10:53:26 +0200 User-Agent: KMail/1.9.1 Cc: Nick Piggin , Magnus Damm , Linux Kernel Mailing List , Linux Memory Management References: <200604281027.22183.ak@suse.de> <2432524299CCD3CA89BB647D@[10.1.1.4]> In-Reply-To: <2432524299CCD3CA89BB647D@[10.1.1.4]> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200604301053.26907.ak@suse.de> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sunday 30 April 2006 08:07, Dave McCracken wrote: > > --On Friday, April 28, 2006 10:27:21 +0200 Andi Kleen wrote: > > >> 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. > > The PGD is always fully populated on i386 if PAE is enabled. All three of > the pmd pages are allocated at page table creation time and persist till > the page table is deleted. At least with the new flexmmap it sounds like a waste of memory. -Andi