From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752457AbaKWUzc (ORCPT ); Sun, 23 Nov 2014 15:55:32 -0500 Received: from mail.skyhub.de ([78.46.96.112]:34434 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752050AbaKWUza (ORCPT ); Sun, 23 Nov 2014 15:55:30 -0500 Date: Sun, 23 Nov 2014 21:55:28 +0100 From: Borislav Petkov To: "Luck, Tony" Cc: rui wang , "linux-kernel@vger.kernel.org" , "gong.chen@linux.intel.com" , "Wang, Rui Y" Subject: Re: [PATCH v3] x86/mce: Try printing all machine check banks known before panic Message-ID: <20141123205527.GB7355@pd.tnic> References: <20141119102954.GA5617@pd.tnic> <3908561D78D1C84285E8C5FCA982C28F3294198E@ORSMSX114.amr.corp.intel.com> <20141120101505.GA791@pd.tnic> <20141121164140.GA4274@pd.tnic> <3908561D78D1C84285E8C5FCA982C28F3294F888@ORSMSX114.amr.corp.intel.com> <20141121181334.GC4274@pd.tnic> <3908561D78D1C84285E8C5FCA982C28F329504FD@ORSMSX114.amr.corp.intel.com> <20141121213547.GF4274@pd.tnic> <3908561D78D1C84285E8C5FCA982C28F32950618@ORSMSX114.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <3908561D78D1C84285E8C5FCA982C28F32950618@ORSMSX114.amr.corp.intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 21, 2014 at 09:59:49PM +0000, Luck, Tony wrote: > > Oh, cpu errata. So this would mean that we can't even rely on the > > contents of the MCA banks, can we? > > > > In any case, is any of the information in the MCA banks in such cases > > even usable then? Because if not, we're definitely barking up the wrong > > tree... > > See above - I think even if there is a bug in the core that isn't setting the > right bits in the MCi_STATUS register - we could get good data from > devices out in the uncore. Btw, since we're talking about errata - I guess you could use X86_BUG and static_cpu_has_bug* to query in do_machine_check and modify logging behavior of mce_log to bypass mce_severity and put all errors of the last round in mce_log and then dump them out at panic time. -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --