From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762617AbWLKHai (ORCPT ); Mon, 11 Dec 2006 02:30:38 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762621AbWLKHai (ORCPT ); Mon, 11 Dec 2006 02:30:38 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:57563 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762617AbWLKHai (ORCPT ); Mon, 11 Dec 2006 02:30:38 -0500 Date: Mon, 11 Dec 2006 08:28:43 +0100 From: Ingo Molnar To: Jarek Poplawski , Andrew Morton , linux-kernel@vger.kernel.org Subject: [patch] lockdep: fix possible race while disabling lock-debugging, restore fix Message-ID: <20061211072843.GB31962@elte.hu> References: <20061207132903.GA341@elte.hu> <20061208062725.GA1012@ff.dom.local> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20061208062725.GA1012@ff.dom.local> User-Agent: Mutt/1.4.2.2i X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -2.6 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.6 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.0.3 -2.6 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Jarek Poplawski wrote: > ... > > @@ -1212,7 +1244,8 @@ register_lock_class(struct lockdep_map * > > hash_head = classhashentry(key); > > > > raw_local_irq_save(flags); > > - __raw_spin_lock(&hash_lock); > > + if (!graph_lock()) > > ! raw_local_irq_restore(flags); > > > + return NULL; yeah. Fix below. Ingo Subject: [patch] lockdep: fix possible race while disabling lock-debugging, restore fix From: Ingo Molnar restore flags in failure branch, pointed out by Jarek Poplawski. Signed-off-by: Ingo Molnar --- kernel/lockdep.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) Index: linux/kernel/lockdep.c =================================================================== --- linux.orig/kernel/lockdep.c +++ linux/kernel/lockdep.c @@ -1244,8 +1244,10 @@ register_lock_class(struct lockdep_map * hash_head = classhashentry(key); raw_local_irq_save(flags); - if (!graph_lock()) + if (!graph_lock()) { + raw_local_irq_restore(flags); return NULL; + } /* * We have to do the hash-walk again, to avoid races * with another CPU: