Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751473AbWE3M3b (ORCPT ); Tue, 30 May 2006 08:29:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751482AbWE3M3a (ORCPT ); Tue, 30 May 2006 08:29:30 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:53426 "EHLO mx3.mail.elte.hu") by vger.kernel.org with ESMTP id S1751472AbWE3M32 (ORCPT ); Tue, 30 May 2006 08:29:28 -0400 Date: Tue, 30 May 2006 14:29:50 +0200 From: Ingo Molnar To: Mike Galbraith Cc: Andrew Morton , linux-kernel@vger.kernel.org Subject: [patch, -rc5-mm1] lock validator: disable NMI watchdog if CONFIG_LOCKDEP, i386 Message-ID: <20060530122950.GA10216@elte.hu> References: <20060530022925.8a67b613.akpm@osdl.org> <20060530111138.GA5078@elte.hu> <1148990326.7599.4.camel@homer> <1148990725.8610.1.camel@homer> <20060530120641.GA8263@elte.hu> <1148991422.8610.8.camel@homer> <20060530121952.GA9625@elte.hu> <1148992098.8700.2.camel@homer> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1148992098.8700.2.camel@homer> User-Agent: Mutt/1.4.2.1i X-ELTE-SpamScore: 0.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=0.0 required=5.9 tests=AWL autolearn=no SpamAssassin version=3.0.3 0.0 AWL AWL: From: address is in the auto white-list X-ELTE-VirusStatus: clean Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1603 Lines: 51 * Mike Galbraith wrote: > > > BUG: warning at kernel/lockdep.c:2398/check_flags() > > > > this one could be related to NMI. We are already disabling NMI on > > x86_64, but i thought i had it fixed up for i386 - apparently not. > > Booted with nmi_watchdog=0, no warning and no deadlock. ok, great. The patch below turns off NMI on i386 automatically. ------------------- Subject: lock validator: disable NMI watchdog if CONFIG_LOCKDEP, i386 From: Ingo Molnar The NMI watchdog uses spinlocks (notifier chains, etc.), so it's not lockdep-safe at the moment. Signed-off-by: Ingo Molnar --- arch/i386/kernel/nmi.c | 11 +++++++++++ 1 file changed, 11 insertions(+) Index: linux/arch/i386/kernel/nmi.c =================================================================== --- linux.orig/arch/i386/kernel/nmi.c +++ linux/arch/i386/kernel/nmi.c @@ -741,6 +741,17 @@ static void stop_intel_arch_watchdog(voi void setup_apic_nmi_watchdog (void *unused) { +#ifdef CONFIG_LOCKDEP + /* + * The NMI watchdog uses spinlocks (notifier chains, etc.), + * so it's not lockdep-safe: + */ + nmi_watchdog = NMI_NONE; + printk("lockdep: disabled NMI watchdog.\n"); + + return; +#endif + /* only support LOCAL and IO APICs for now */ if ((nmi_watchdog != NMI_LOCAL_APIC) && (nmi_watchdog != NMI_IO_APIC)) - 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/