Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754739Ab0HQH4e (ORCPT ); Tue, 17 Aug 2010 03:56:34 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:54100 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752692Ab0HQH4d (ORCPT ); Tue, 17 Aug 2010 03:56:33 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=thMqsotLPGddp5l0ws9Wv1kPuwEuOofrBFSG5lI50EEEvzmjeIJwkqP3pcKDLNEeTv KeFOHNRsK2gB503i5nW6tuMH/icdjqqViHTRMLrgKnS2DcH1RkSGFBuYi6zzesYRhOk+ 03zeZWCuyI5RV34L6aiJxaZxZroEo0lTTVyLI= Date: Tue, 17 Aug 2010 10:56:12 +0300 From: Sergey Senozhatsky To: Frederic Weisbecker Cc: Peter Zijlstra , Don Zickus , Andrew Morton , Ingo Molnar , linux-kernel@vger.kernel.org Subject: [PATCH] fix BUG using smp_processor_id() in touch_nmi_watchdog and touch_softlockup_watchdog (v2) Message-ID: <20100817075612.GA5346@swordfish.minsk.epam.com> References: <20100813102158.GA5434@swordfish.minsk.epam.com> <1281946970.1926.998.camel@laptop> <20100816133452.GS4879@redhat.com> <1281966418.1926.1421.camel@laptop> <20100816140829.GA5225@swordfish.minsk.epam.com> <20100817025954.GA12366@nowhere> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100817025954.GA12366@nowhere> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1461 Lines: 49 Fix: acpi_os_stall calls touch_nmi_watchdog and touch_softlockup_watchdog with preemption enabled causing 'BUG: using smp_processor_id() in preemptible code'. Patch also removes double smp_processor_id call (smp_processor_id itself and in __get_cpu_var) in __touch_watchdog. Signed-off-by: Sergey Senozhatsky --- diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 613bc1f..cb4f4d4 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -116,13 +116,14 @@ static unsigned long get_sample_period(void) static void __touch_watchdog(void) { int this_cpu = smp_processor_id(); - - __get_cpu_var(watchdog_touch_ts) = get_timestamp(this_cpu); + per_cpu(watchdog_touch_ts, this_cpu) = get_timestamp(this_cpu); } void touch_softlockup_watchdog(void) { + preempt_disable(); __get_cpu_var(watchdog_touch_ts) = 0; + preempt_enable(); } EXPORT_SYMBOL(touch_softlockup_watchdog); @@ -142,7 +143,10 @@ void touch_all_softlockup_watchdogs(void) #ifdef CONFIG_HARDLOCKUP_DETECTOR void touch_nmi_watchdog(void) { + preempt_disable(); __get_cpu_var(watchdog_nmi_touch) = true; + preempt_enable(); + touch_softlockup_watchdog(); } EXPORT_SYMBOL(touch_nmi_watchdog); -- 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/