From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1423286Ab3FUHec (ORCPT ); Fri, 21 Jun 2013 03:34:32 -0400 Received: from mail.skyhub.de ([78.46.96.112]:43383 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933901Ab3FUHea (ORCPT ); Fri, 21 Jun 2013 03:34:30 -0400 Date: Fri, 21 Jun 2013 09:34:19 +0200 From: Borislav Petkov To: "Naveen N. Rao" 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 1/2] mce: acpi/apei: Honour Firmware First for MCA banks listed in APEI HEST CMC Message-ID: <20130621073419.GC22006@pd.tnic> References: <20130619175438.2852.93449.stgit@localhost.localdomain> <20130620073943.GE32694@pd.tnic> <51C3531D.3000600@linux.vnet.ibm.com> <20130620192928.GD19877@pd.tnic> <51C36288.4050405@linux.vnet.ibm.com> <20130620205726.GA20863@pd.tnic> <51C37291.40303@linux.vnet.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <51C37291.40303@linux.vnet.ibm.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 On Fri, Jun 21, 2013 at 02:52:25AM +0530, Naveen N. Rao wrote: > Exactly, but mce_poll_banks also doesn't have bits set for banks on > which CMCI is enabled. > > Let's say we have a cpu with 2 banks (not shared), none of which work > in FF mode. Both these banks support CMCI, so mce_poll_banks won't > have these bits set. > > On cpu offline, we call cmci_clear() which disables CMCI on these two > banks before offlining it. When this cpu is brought online again, we > call cmci_discover() which sees that mce_poll_banks doesn't have these > two banks enabled and will skip enabling CMCI thinking these are in > FF. Hmm, mce_intel has yet another bitfield - mce_banks_owned. (Btw, this is why I have a problem with adding yet another bitfield). The way I understand it is, if a bit is set in the owned bitfield, those banks belong to CMCI and are not polled. Now, can we use both mce_banks_owned and mce_poll_banks? If a bit in both bifields is cleared, the corresponding bank is not polled *and* is not owned by CMCI => it is in FF mode. Makes sense? -- Regards/Gruss, Boris. Sent from a fat crate under my desk. Formatting is fine. --