From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935058Ab3FSSR6 (ORCPT ); Wed, 19 Jun 2013 14:17:58 -0400 Received: from e28smtp02.in.ibm.com ([122.248.162.2]:59862 "EHLO e28smtp02.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934170Ab3FSSR5 (ORCPT ); Wed, 19 Jun 2013 14:17:57 -0400 Message-ID: <51C1F5CB.9020005@linux.vnet.ibm.com> Date: Wed, 19 Jun 2013 23:47:47 +0530 From: "Naveen N. Rao" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130514 Thunderbird/17.0.6 MIME-Version: 1.0 To: Borislav Petkov CC: tony.luck@intel.com, ananth@in.ibm.com, masbock@linux.vnet.ibm.com, lcm@linux.vnet.ibm.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, ying.huang@intel.com Subject: Re: [PATCH v2 2/2] mce: acpi/apei: Add a boot option to disable ff mode for corrected errors References: <20130619175438.2852.93449.stgit@localhost.localdomain> <20130619175728.2852.73156.stgit@localhost.localdomain> <20130619180441.GK28300@pd.tnic> In-Reply-To: <20130619180441.GK28300@pd.tnic> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-MML: No X-Content-Scanned: Fidelis XPS MAILER x-cbid: 13061918-5816-0000-0000-000008863D34 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/19/2013 11:34 PM, Borislav Petkov wrote: > On Wed, Jun 19, 2013 at 11:27:42PM +0530, Naveen N. Rao wrote: >> Add a boot option to disable firmware first mode for corrected errors. >> >> Signed-off-by: Naveen N. Rao >> --- >> Documentation/x86/x86_64/boot-options.txt | 5 +++++ >> arch/x86/include/asm/acpi.h | 2 ++ >> arch/x86/kernel/acpi/boot.c | 5 +++++ >> drivers/acpi/apei/hest.c | 3 ++- >> 4 files changed, 14 insertions(+), 1 deletion(-) >> >> diff --git a/Documentation/x86/x86_64/boot-options.txt b/Documentation/x86/x86_64/boot-options.txt >> index e9e8ddb..1228b22 100644 >> --- a/Documentation/x86/x86_64/boot-options.txt >> +++ b/Documentation/x86/x86_64/boot-options.txt >> @@ -176,6 +176,11 @@ ACPI >> >> acpi=noirq Don't route interrupts >> >> + acpi=nocmcff Disable firmware first mode for corrected errors. This >> + disables parsing the HEST CMC error source to check if >> + firmware has set the FF flag. This may result in >> + duplicate corrected error reports. > > Interesting, why? Why would we even need such an option? My impression > is, if ACPI tells us FF, MCE code doesn't poll those banks anymore. So > where do the duplicated reports come from? This option is a way to revert to the existing behavior where we continue to enable CMCI/poll. If we enable this option, then we will receive error events from CMCI/polling as well as from the firmware through GHES. Thanks, Naveen