Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932772AbVITRay (ORCPT ); Tue, 20 Sep 2005 13:30:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932777AbVITRay (ORCPT ); Tue, 20 Sep 2005 13:30:54 -0400 Received: from smtp.osdl.org ([65.172.181.4]:49817 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S932773AbVITRax (ORCPT ); Tue, 20 Sep 2005 13:30:53 -0400 Date: Tue, 20 Sep 2005 10:30:48 -0700 (PDT) From: Linus Torvalds To: Charles McCreary cc: linux-kernel@vger.kernel.org Subject: Re: x86-64 bad pmds in 2.6.11.6 In-Reply-To: <200509201212.55676.mccreary@crmeng.com> Message-ID: References: <200509201212.55676.mccreary@crmeng.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2104 Lines: 68 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); - 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/