From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932150AbVJCElN (ORCPT ); Mon, 3 Oct 2005 00:41:13 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932151AbVJCElN (ORCPT ); Mon, 3 Oct 2005 00:41:13 -0400 Received: from gold.veritas.com ([143.127.12.110]:59536 "EHLO gold.veritas.com") by vger.kernel.org with ESMTP id S932150AbVJCElN (ORCPT ); Mon, 3 Oct 2005 00:41:13 -0400 Date: Mon, 3 Oct 2005 05:40:39 +0100 (BST) From: Hugh Dickins X-X-Sender: hugh@goblin.wat.veritas.com To: Christian Seiler cc: linux-kernel@vger.kernel.org Subject: Re: Bug at mm/rmap.c:493, Kernel 2.6.13.2 In-Reply-To: <4340108F.7030604@selfhtml.org> Message-ID: References: <4340108F.7030604@selfhtml.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-OriginalArrivalTime: 03 Oct 2005 04:41:12.0768 (UTC) FILETIME=[AEAFD400:01C5C7D4] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2 Oct 2005, Christian Seiler wrote: > > In the kernel log of a computer I'm administrating a strange message > appeared stating there was a kernel bug in mm/rmap.c, line 493. I put > together the kernel log message (including the stack trace), the kernel > configuration, the output of lspci -v, lsmod, uname -a and gcc/ld > -version here: > > http://src.selfhtml.org/lkml/ > > Although the message says a reboot is needed, the server still seems to > work after that message (login using SSH is possible, all services still > respond normally). After a reboot the same message reappears inside the > log after some time. > > The distribution is Gentoo Linux, but the kernel is built from vanilla > sources. The system is entirely 64bit - no 32bit libraries are > installed. The server itself is a Sun Fire V20z with two Opteron 244, 2 > GiB of RAM and hardware RAID-1 with two U320 SCSI disks. Please try Linus' patch at the bottom: on dual Opteron, our best guess is that yours is a different manifestation of the same underlying issue. (I believe there's now a more finely targetted version of the patch in -rc3, but this will do if it is your problem). Please get back to me if you find this doesn't fix it - thanks. Here's what Linus said on 20 Sep: On Tue, 20 Sep 2005, Charles McCreary wrote: > > Another datapoint for this thread. The box spewing the bad pmds messages is a > dual opteron 246 on a TYAN S2885 Thunder K8W motherboard. Kernel is > 2.6.11.4-20a-smp. This is quite possibly the result of an Opteron errata (tlb flush filtering is broken on SMP) that we worked around as of 2.6.14-rc4. So either just try 2.6.14-rc2, or try the appended patch (it has since been confirmed by many more people). Linus --- diff-tree bc5e8fdfc622b03acf5ac974a1b8b26da6511c99 (from 61ffcafafb3d985e1ab8463be0187b421614775c) Author: Linus Torvalds Date: Sat Sep 17 15:41:04 2005 -0700 x86-64/smp: fix random SIGSEGV issues They seem to have been due to AMD errata 63/122; the fix is to disable TLB flush filtering in SMP configurations. Confirmed to fix the problem by Andrew Walrond [ Let's see if we'll have a better fix eventually, this is the Q&D "let's get this fixed and out there" version ] Signed-off-by: Linus Torvalds diff --git a/arch/x86_64/kernel/setup.c b/arch/x86_64/kernel/setup.c --- a/arch/x86_64/kernel/setup.c +++ b/arch/x86_64/kernel/setup.c @@ -831,11 +831,26 @@ static void __init amd_detect_cmp(struct #endif } +#define HWCR 0xc0010015 + static int __init init_amd(struct cpuinfo_x86 *c) { int r; int level; +#ifdef CONFIG_SMP + unsigned long value; + + // Disable TLB flush filter by setting HWCR.FFDIS: + // bit 6 of msr C001_0015 + // + // Errata 63 for SH-B3 steppings + // Errata 122 for all(?) steppings + rdmsrl(HWCR, value); + value |= 1 << 6; + wrmsrl(HWCR, value); +#endif + /* Bit 31 in normal CPUID used for nonstandard 3DNow ID; 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway */ clear_bit(0*32+31, &c->x86_capability);