From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752582AbYJ0Alq (ORCPT ); Sun, 26 Oct 2008 20:41:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751253AbYJ0Ali (ORCPT ); Sun, 26 Oct 2008 20:41:38 -0400 Received: from terminus.zytor.com ([198.137.202.10]:60127 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751197AbYJ0Alh (ORCPT ); Sun, 26 Oct 2008 20:41:37 -0400 Message-ID: <49050D7F.4000906@zytor.com> Date: Sun, 26 Oct 2008 17:38:23 -0700 From: "H. Peter Anvin" User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Arjan van de Ven CC: "Diego M. Vadell" , Linux Kernel Subject: Re: PAT and MTRRs References: <200810262246.21807.dvadell@linuxclusters.com.ar> <20081026171210.7b3b096a@infradead.org> <49050995.4080508@zytor.com> <20081026173458.44c5a036@infradead.org> In-Reply-To: <20081026173458.44c5a036@infradead.org> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Arjan van de Ven wrote: >>> >> Now, if it wasn't for the braindamage called ACPI and SMM, we could >> have cleared the MTRR settings and just used PAT... > > yeah.. one thing we need to investigate is if we can set the default > "no mtrr coverage" value to cached > (and also.. to check we don't set that to uncached if the bios had it > set to cached..) > Well, in the end it comes down to the same thing: SMM expects the memory map to reside in MTRRs. We can "sanitize" the memory map, but we can't throw it out the window like what we really should be able to. -hpa