From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758463AbYGBPHu (ORCPT ); Wed, 2 Jul 2008 11:07:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757884AbYGBPHR (ORCPT ); Wed, 2 Jul 2008 11:07:17 -0400 Received: from smtp-01.oit.duke.edu ([152.3.174.14]:53712 "EHLO smtp.duke.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757389AbYGBPHO (ORCPT ); Wed, 2 Jul 2008 11:07:14 -0400 X-Greylist: delayed 722 seconds by postgrey-1.27 at vger.kernel.org; Wed, 02 Jul 2008 11:07:14 EDT Date: Wed, 2 Jul 2008 10:55:10 -0400 (EDT) From: Rann Bar-On X-X-Sender: rann@localhost Reply-To: rb6@duke.edu To: linux-kernel@vger.kernel.org Subject: mtrr registers with >= 4GB ram Message-ID: User-Agent: Alpine 1.10 (LNX 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; format=flowed; charset=US-ASCII X-PMX-Version: 5.4.2.338381, Antispam-Engine: 2.6.0.325393, Antispam-Data: 2008.7.2.144155 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As documented at https://bugs.launchpad.net/linux/+bug/210780 and http://www.rage3d.com/board/showthread.php?t=33821469 (as well as other places - google 4gb mtrr bug), the kernel appears to misdetect the mtrr registers on many machines with 4gb ram, causing all sorts of issues - especially with video drivers in X. It is possible to rewrite the correct registers using a pretty hackish script, but the bug should probably be fixed at the kernel level. Please CC me personally when replying, as I'm not on LKML. I'd be happy to try out patches if such come along :) Thanks, Rann