Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759326AbXE3X3b (ORCPT ); Wed, 30 May 2007 19:29:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753171AbXE3X3V (ORCPT ); Wed, 30 May 2007 19:29:21 -0400 Received: from shawidc-mo1.cg.shawcable.net ([24.71.223.10]:3929 "EHLO pd2mo2so.prod.shaw.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753882AbXE3X3V (ORCPT ); Wed, 30 May 2007 19:29:21 -0400 Date: Wed, 30 May 2007 17:29:17 -0600 From: Robert Hancock Subject: Re: Case: 7454422: Re: Kernel 2.6.21.3 does not work with 8GB of RAM on Intel 965WH motherboards. (FULL DMESG) In-reply-to: To: Justin Piszcz Cc: linux-kernel@vger.kernel.org, crmotherboard@mailbox.cps.intel.com Message-id: <465E08CD.2080302@shaw.ca> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1 Content-transfer-encoding: 7bit References: User-Agent: Thunderbird 2.0.0.0 (Windows/20070326) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2511 Lines: 66 Justin Piszcz wrote: > That output looked nasty, attaching entries from syslog. > > Justin. Here's your E820 memory map, from dmesg: BIOS-e820: 0000000000000000 - 000000000008f000 (usable) BIOS-e820: 000000000008f000 - 00000000000a0000 (reserved) BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved) BIOS-e820: 0000000000100000 - 00000000cf58f000 (usable) BIOS-e820: 00000000cf58f000 - 00000000cf59c000 (reserved) BIOS-e820: 00000000cf59c000 - 00000000cf653000 (usable) BIOS-e820: 00000000cf653000 - 00000000cf6a5000 (ACPI NVS) BIOS-e820: 00000000cf6a5000 - 00000000cf6a8000 (ACPI data) BIOS-e820: 00000000cf6a8000 - 00000000cf6ef000 (ACPI NVS) BIOS-e820: 00000000cf6ef000 - 00000000cf6f1000 (ACPI data) BIOS-e820: 00000000cf6f1000 - 00000000cf6f2000 (usable) BIOS-e820: 00000000cf6f2000 - 00000000cf6ff000 (ACPI data) BIOS-e820: 00000000cf6ff000 - 00000000cf700000 (usable) BIOS-e820: 00000000cf700000 - 00000000d0000000 (reserved) BIOS-e820: 00000000fff00000 - 0000000100000000 (reserved) BIOS-e820: 0000000100000000 - 000000022c000000 (usable) so the usable memory ranges are: 0-572K 1MB-3317.55MB 3317.60MB-3317.75MB 3318.94MB-3318.945MB 3318.996MB-3319MB 4096MB-8896MB and the MTRRs (from /proc/mtrr, from private email): reg00: base=0x00000000 ( 0MB), size=2048MB: write-back, count=1 reg01: base=0x80000000 (2048MB), size=1024MB: write-back, count=1 reg02: base=0xc0000000 (3072MB), size= 256MB: write-back, count=1 reg03: base=0xcf800000 (3320MB), size= 8MB: uncachable, count=1 reg04: base=0xcf700000 (3319MB), size= 1MB: uncachable, count=1 reg05: base=0x100000000 (4096MB), size=4096MB: write-back, count=1 reg06: base=0x200000000 (8192MB), size= 512MB: write-back, count=1 reg07: base=0x220000000 (8704MB), size= 128MB: write-back, count=1 so the ranges mapped as cacheable are: 0-3319MB 4096-8832MB leaving 64MB of memory at the top of RAM uncached. What do you want to bet that something important (kernel code?) is getting loaded there.. So essentially it's a BIOS problem, it's not setting up the MTRRs properly in order to map all of RAM as cacheable. As Andi says, complain to Intel. -- Robert Hancock Saskatoon, SK, Canada To email, remove "nospam" from hancockr@nospamshaw.ca Home Page: http://www.roberthancock.com/ - 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/