From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753872AbYHUBUU (ORCPT ); Wed, 20 Aug 2008 21:20:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752025AbYHUBUG (ORCPT ); Wed, 20 Aug 2008 21:20:06 -0400 Received: from rv-out-0506.google.com ([209.85.198.228]:4029 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751958AbYHUBUE (ORCPT ); Wed, 20 Aug 2008 21:20:04 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=F12f1DLjFwDDZ+fnfEnuBUgn65b1gTT+o68a0v10R0kBLNwRcOvDbQ0Z7N+dZb7N2R D/39vAxSuOlOexj2AkBlrzrU0hxNkHtEgrzSvGRsakmbq+XkfKUMYWu8tTszlgAwdqEg L48JG3MTOli0oTiIar9QRJgFdqQkCzwfuoEew= Message-ID: <86802c440808201820w6c684a10y2f1d0f70a344a14a@mail.gmail.com> Date: Wed, 20 Aug 2008 18:20:03 -0700 From: "Yinghai Lu" To: "Andrew Morton" Subject: Re: [Bug 11388] New: 2.6.27-rc3 warns about MTRR range; only 3 of 16gb of memory is usable Cc: bugme-daemon@bugzilla.kernel.org, linux-kernel@vger.kernel.org, j_kernel@hoblitt.com In-Reply-To: <20080820180405.7f164450.akpm@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20080820180405.7f164450.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Aug 20, 2008 at 6:04 PM, Andrew Morton wrote: > > (switched to email. Please respond via emailed reply-to-all, not via the > bugzilla web interface). > > On Wed, 20 Aug 2008 17:38:59 -0700 (PDT) > bugme-daemon@bugzilla.kernel.org wrote: > >> http://bugzilla.kernel.org/show_bug.cgi?id=11388 >> >> Summary: 2.6.27-rc3 warns about MTRR range; only 3 of 16gb of >> memory is usable >> Product: Memory Management >> Version: 2.5 >> KernelVersion: 2.6.27-rc3 >> Platform: All >> OS/Version: Linux >> Tree: Mainline >> Status: NEW >> Severity: normal >> Priority: P1 >> Component: MTTR >> AssignedTo: akpm@osdl.org >> ReportedBy: j_kernel@hoblitt.com >> >> >> Latest working kernel version: 2.4.24.2 (possibly later) >> Earliest failing kernel version: 2.6.27-rc3-21328-ga7f5aaf (from netdev-2.6) >> Distribution: Gentoo >> Hardware Environment: 2x Intel X5482 >> Software Environment: >> Problem Description: >> >> [ 0.000000] WARNING: BIOS bug: CPU MTRRs don't cover all of memory, losing >> 13056MB of RAM. >> [ 0.000000] ------------[ cut here ]------------ >> [ 0.000000] WARNING: at arch/x86/kernel/cpu/mtrr/main.c:1561 >> mtrr_trim_uncached_memory+0x508/0x550() >> [ 0.000000] Modules linked in: >> [ 0.000000] Pid: 0, comm: swapper Not tainted 2.6.27-rc3-21328-ga7f5aaf #8 >> [ 0.000000] >> [ 0.000000] Call Trace: >> [ 0.000000] [] warn_on_slowpath+0x51/0x77 >> [ 0.000000] [] printk+0x4e/0x56 >> [ 0.000000] [] sort+0xfa/0x18c >> [ 0.000000] [] cmp_range+0x0/0x6 >> [ 0.000000] [] mtrr_trim_uncached_memory+0x508/0x550 >> [ 0.000000] [] post_set+0x20/0x3d >> [ 0.000000] [] setup_arch+0x39d/0x6be >> [ 0.000000] [] start_kernel+0x74/0x341 >> [ 0.000000] [] x86_64_start_kernel+0xe3/0xe7 >> [ 0.000000] >> [ 0.000000] ---[ end trace 4eaa2a86a8e2da22 ]--- >> >> >> Steps to reproduce: >> >> This warning isn't present under 2.6.24.2 and the full range of physical memory >> is usable. > > Looks like a post-2.6.26 regression caused by > 12031a624af7816ec7660b82be648aa3703b4ebe. reg00: base=0xd0000000 (3328MB), size=196864MB: uncachable, count=1 reg01: base=0xe0000000 (3584MB), size=197120MB: uncachable, count=1 reg02: base=0x00000000 ( 0MB), size=212992MB: write-back, count=1 reg03: base=0x400000000 (16384MB), size=197120MB: write-back, count=1 reg04: base=0x420000000 (16896MB), size=196864MB: write-back, count=1 the size mtrr looks crazy. YH