From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752073Ab1GYKjb (ORCPT ); Mon, 25 Jul 2011 06:39:31 -0400 Received: from gold.linx.net ([195.66.232.40]:35798 "EHLO gold.linx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751970Ab1GYKjZ (ORCPT ); Mon, 25 Jul 2011 06:39:25 -0400 From: Tony Vroon To: LKML Cc: Thomas Gleixner Cc: Ingo Molnar Cc: "H. Peter Anvin" Subject: Re: MTRR setup failure on Fujitsu Lifebook S761 In-Reply-To: <20110722081225.2272F10082@gold.linx.net> Message-Id: <20110725103922.5718910089@gold.linx.net> Date: Mon, 25 Jul 2011 11:39:22 +0100 (BST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/22/11 09:12, Tony Vroon wrote: > The contents of /proc/mtrr are: > reg00: base=0x0ffc00000 ( 4092MB), size= 4MB, count=1: write-protect > reg01: base=0x000000000 ( 0MB), size= 2048MB, count=1: write-back > reg02: base=0x080000000 ( 2048MB), size= 1024MB, count=1: write-back > reg03: base=0x0c0000000 ( 3072MB), size= 512MB, count=1: write-back > reg04: base=0x0d0000000 ( 3328MB), size= 256MB, count=1: uncachable > reg05: base=0x0cc000000 ( 3264MB), size= 64MB, count=1: uncachable > reg06: base=0x0cb000000 ( 3248MB), size= 16MB, count=1: uncachable > reg07: base=0x0cac00000 ( 3244MB), size= 4MB, count=1: uncachable > reg08: base=0x100000000 ( 4096MB), size= 1024MB, count=1: write-back > reg09: base=0x130000000 ( 4864MB), size= 256MB, count=1: uncachable I believe this is closer to the optimum: adrastea ~ # cat /proc/mtrr reg00: base=0x0ffc00000 ( 4092MB), size= 4MB, count=1: write-protect reg01: base=0x000000000 ( 0MB), size= 2048MB, count=1: write-back reg02: base=0x080000000 ( 2048MB), size= 1024MB, count=1: write-back reg03: base=0x0c0000000 ( 3072MB), size= 256MB, count=1: write-back reg04: base=0x0d0000000 ( 3328MB), size= 256MB, count=1: write-combining reg05: base=0x100000000 ( 4096MB), size= 1024MB, count=1: write-back reg09: base=0x130000000 ( 4864MB), size= 256MB, count=1: uncachable 0x0d0000000 is the range triggering the warning before, it is the AGP aperture for the Sandy Bridge graphics. I used the following script to get there: adrastea ~ # cat /usr/sbin/mtrr.sh #!/bin/bash echo "disable=3" >| /proc/mtrr echo "disable=4" >| /proc/mtrr echo "disable=5" >| /proc/mtrr echo "disable=6" >| /proc/mtrr echo "disable=7" >| /proc/mtrr echo "disable=8" >| /proc/mtrr echo "base=0xc0000000 size=0x10000000 type=write-back" >| /proc/mtrr echo "base=0xd0000000 size=0x10000000 type=write-combining" >| /proc/mtrr echo "base=0x100000000 size=0x40000000 type=write-back" >| /proc/mtrr Two questions remain... 1) Why can't the MTRR sanitizer figure this one out? (Even on 3.0.0-03370-gb6844e8) 2) If the MTRR sanitizer will not be fixed, how can I override the above MTRRs on the kernel command line? Regards, -- Tony Vroon UNIX systems administrator London Internet Exchange Ltd, Trinity Court, Trinity Street, Peterborough, PE1 1DA Registered in England number 3137929 E-Mail: tony@linx.net