Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753683AbZJBSrk (ORCPT ); Fri, 2 Oct 2009 14:47:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752351AbZJBSrk (ORCPT ); Fri, 2 Oct 2009 14:47:40 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:53940 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751038AbZJBSrj (ORCPT ); Fri, 2 Oct 2009 14:47:39 -0400 Date: Fri, 2 Oct 2009 20:47:14 +0200 From: Ingo Molnar To: Borislav Petkov Cc: Linus Torvalds , Borislav Petkov , Andi Kleen , x86@kernel.org, Linux Kernel Mailing List Subject: Re: [PATCH 3/3] EDAC: carve out AMD MCE decoding logic Message-ID: <20091002184714.GA21509@elte.hu> References: <20091001141432.GA11410@aftab> <20091001144637.GB11410@aftab> <20091001150046.GA21476@elte.hu> <20091001152140.GC11410@aftab> <20091001153250.GA25885@elte.hu> <20091002132101.GA28682@aftab> <20091002133148.GD28682@aftab> <20091002133954.GA29390@elte.hu> <20091002182659.GA16436@aftab> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091002182659.GA16436@aftab> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1287 Lines: 34 * Borislav Petkov wrote: > On Fri, Oct 02, 2009 at 03:39:54PM +0200, Ingo Molnar wrote: > > I suspect this is fine currently because no two EDAC modules should be > > active at the same time. A followup cleanup patch would be nice > > nevertheless that uses a notifier chain here with proper > > register/unregister locking. > > Please do elaborate for I can't seem to follow. > > AFAICT, we are going to have max one MCE decoder at any one time so no > need to notify it. > > The x86_mce_decode_callback assignment probably needs locking just to > be on the safe side. We can do a > > mce_set_decode_callback(void (*f)(struct mce*m)) > > helper which falls back to default_decode_mce() whenever its being > passed a NULL for *f using proper locking... > > I'm pretty sure I'm missing something though... No, the locking was all that i meant. Using atomic_notifier would solve that. Make the default decoder low-prio, that way there's no need to do the callback save/restore sequence either. Ingo -- 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/