Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764115AbXFAVIL (ORCPT ); Fri, 1 Jun 2007 17:08:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762327AbXFAVH6 (ORCPT ); Fri, 1 Jun 2007 17:07:58 -0400 Received: from outbound-mail-42.bluehost.com ([69.89.18.11]:47981 "HELO outbound-mail-42.bluehost.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1762129AbXFAVH5 (ORCPT ); Fri, 1 Jun 2007 17:07:57 -0400 From: Jesse Barnes To: Andi Kleen Subject: Re: Intel's response Linux/MTRR/8GB Memory Support / Why doesn't the kernel realize the BIOS has problems and re-map appropriately? Date: Fri, 1 Jun 2007 14:07:51 -0700 User-Agent: KMail/1.9.6 Cc: Justin Piszcz , linux-kernel@vger.kernel.org References: <200706011210.15808.jbarnes@virtuousgeek.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200706011407.51779.jbarnes@virtuousgeek.org> X-Identified-User: {642:box128.bluehost.com:virtuous:virtuousgeek.org} {sentby:smtp auth 76.102.120.196 authed with jbarnes@virtuousgeek.org} Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1108 Lines: 24 On Friday, June 1, 2007 2:14:17 Andi Kleen wrote: > Jesse Barnes writes: > > (or we get proper PAT support, which I think would make this problem > > go away as well). > > No it won't. If the basic MTRRs for memory are wrong just having PAT > support in drivers (which already exist in a limited form already, just for > UC only) won't change anything. No obviously just using PAT for drivers wouldn't help, I was thinking more of having one PAT type be WB memory, and using it by default for most PTEs covering normal memory. If that's not possible, then it seems sensible to try to fix this MTRR problem in a better way, either with something like the patch I posted earlier or a more advanced MTRR remapper that runs at early boot. Depending on platform requirements though, that could get complicated pretty fast... Jesse - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/