From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757680Ab0JVSue (ORCPT ); Fri, 22 Oct 2010 14:50:34 -0400 Received: from kroah.org ([198.145.64.141]:45734 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757154Ab0JVSii (ORCPT ); Fri, 22 Oct 2010 14:38:38 -0400 X-Mailbox-Line: From gregkh@clark.site Fri Oct 22 11:35:59 2010 Message-Id: <20101022183559.080271578@clark.site> User-Agent: quilt/0.48-11.2 Date: Fri, 22 Oct 2010 11:34:59 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Borislav Petkov , Ingo Molnar Subject: [32/66] x86, AMD, MCE thresholding: Fix the MCi_MISCj iteration order In-Reply-To: <20101022183711.GA23214@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: Borislav Petkov commit 6dcbfe4f0b4e17e289d56fa534b7ce5a6b7f63a3 upstream. This fixes possible cases of not collecting valid error info in the MCE error thresholding groups on F10h hardware. The current code contains a subtle problem of checking only the Valid bit of MSR0000_0413 (which is MC4_MISC0 - DRAM thresholding group) in its first iteration and breaking out if the bit is cleared. But (!), this MSR contains an offset value, BlkPtr[31:24], which points to the remaining MSRs in this thresholding group which might contain valid information too. But if we bail out only after we checked the valid bit in the first MSR and not the block pointer too, we miss that other information. The thing is, MC4_MISC0[BlkPtr] is not predicated on MCi_STATUS[MiscV] or MC4_MISC0[Valid] and should be checked prior to iterating over the MCI_MISCj thresholding group, irrespective of the MC4_MISC0[Valid] setting. Signed-off-by: Borislav Petkov Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/mcheck/mce_amd.c | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) --- a/arch/x86/kernel/cpu/mcheck/mce_amd.c +++ b/arch/x86/kernel/cpu/mcheck/mce_amd.c @@ -140,6 +140,7 @@ void mce_amd_feature_init(struct cpuinfo address = (low & MASK_BLKPTR_LO) >> 21; if (!address) break; + address += MCG_XBLK_ADDR; } else ++address; @@ -147,12 +148,8 @@ void mce_amd_feature_init(struct cpuinfo if (rdmsr_safe(address, &low, &high)) break; - if (!(high & MASK_VALID_HI)) { - if (block) - continue; - else - break; - } + if (!(high & MASK_VALID_HI)) + continue; if (!(high & MASK_CNTP_HI) || (high & MASK_LOCKED_HI))