Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757590Ab2JQSJQ (ORCPT ); Wed, 17 Oct 2012 14:09:16 -0400 Received: from mail.x86-64.org ([217.9.48.20]:52213 "EHLO mail.x86-64.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752080Ab2JQSJM convert rfc822-to-8bit (ORCPT ); Wed, 17 Oct 2012 14:09:12 -0400 Date: Wed, 17 Oct 2012 20:09:09 +0200 From: Borislav Petkov To: "Luck, Tony" Cc: Borislav Petkov , "Naveen N. Rao" , "gong.chen@linux.intel.com" , "ananth@in.ibm.com" , "masbock@linux.vnet.ibm.com" , "x86@kernel.org" , "linux-kernel@vger.kernel.org" , "lcm@us.ibm.com" , "andi@firstfloor.org" , "hpa@zytor.com" , "tglx@linutronix.de" , "mingo@redhat.com" , "gregkh@suse.de" , "linux-edac@vger.kernel.org" Subject: Re: [PATCH v3] x86/mce: Honour bios-set CMCI threshold Message-ID: <20121017180909.GB31503@aftab.osrc.amd.com> References: <20120912122516.3825.87838.stgit@localhost.localdomain> <505C51D8.6070402@linux.vnet.ibm.com> <20121017105940.GA14590@x1.osrc.amd.com> <507E9622.6090606@linux.vnet.ibm.com> <20121017130934.GB14590@x1.osrc.amd.com> <507ED31B.7010402@linux.vnet.ibm.com> <20121017164006.GA14596@x1.osrc.amd.com> <3908561D78D1C84285E8C5FCA982C28F19D517FF@ORSMSX108.amr.corp.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <3908561D78D1C84285E8C5FCA982C28F19D517FF@ORSMSX108.amr.corp.intel.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2221 Lines: 55 On Wed, Oct 17, 2012 at 05:28:11PM +0000, Luck, Tony wrote: > > What's wrong with userspace tools parsing /proc/cmdline and seeing that > > mce_bios_cmci_threshold has been set since this is the only way to set > > it anyway? > > The argument might be on the command line, but may have been rejected > because the BIOS didn't set the thresholds? So then you'd have to look at > the command line, *and* check /var/log/messages to make sure we hadn't > printed the message saying the BIOS was unsupportive. Right, but the sysfs read-only thing doesn't solve that either - it only dumps the mce_bios_cmci_threshold value so it doesn't help. The stuff you're talking about is not reflected in that variable but saved in some other like bios_wrong_thresh and bios_zero_thresh. > BUT ... I don't think that knowing this is sufficient. A userspace > tool would want to know what value had been set for each bank. So if > it really wants to do something interesting, just knowing that "bios > set some thresholds" doesn't sound like enough information. Yes. And I still haven't gotten a real use case of what userspace tool will do with this information. > BUT (squared) do you even really need to know that thresholds were > set? You could look at bits {52:38} in the MCi_STATUS information for > the bank to see how many corrected errors had been logged. Right, a real use case which shows why we need that information should be good. Thanks. > -Tony > �{.n�+�������+%��lzwm��b�맲��r��zX���iȧ���ܨ}���Ơz�&j:+v�������zZ+��+zf���h���~����i���z��w���?����&�)ߢf What happened here? It seems your mail client wanted to say something too but it has been censored. :-) -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- 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/