Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754967AbYJ2Ui2 (ORCPT ); Wed, 29 Oct 2008 16:38:28 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752763AbYJ2UiT (ORCPT ); Wed, 29 Oct 2008 16:38:19 -0400 Received: from mx2.redhat.com ([66.187.237.31]:42753 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752652AbYJ2UiS (ORCPT ); Wed, 29 Oct 2008 16:38:18 -0400 Date: Wed, 29 Oct 2008 16:39:19 -0400 From: Aristeu Rozanski To: "Maciej W. Rozycki" Cc: Randy Dunlap , linux-kernel@vger.kernel.org, Ingo Molnar Subject: Re: [PATCH 1/2] NMI watchdog: add support to enable and disable IOAPIC NMI Message-ID: <20081029203918.GN771@redhat.com> References: <20081027164233.132189000@napanee.usersys.redhat.com> <20081027164234.679734000@napanee.usersys.redhat.com> <20081029090532.cc9536d9.randy.dunlap@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1629 Lines: 36 > > > This patch adds support to enable/disable IOAPIC NMI watchdog in runtime via > > > procfs. > > > > Some info on how to use this, what to write(?) to what file(?) in procfs > > would be Very Good to have. > > I gather this is an extension to the existing interface already covering > the local APIC NMI watchdog, which surely ;) must have been documented at > the time it was added. If it wasn't, then we cannot require it now as a > prerequisite to accept this patch, although such documentation would be > desirable as a separate submission. What about (if OK, I'll resubmit in a different thread with proper format): --- Documentation/nmi_watchdog.txt | 5 +++++ 1 file changed, 5 insertions(+) --- linus-2.6.orig/Documentation/nmi_watchdog.txt 2008-10-24 11:41:30.000000000 -0400 +++ linus-2.6/Documentation/nmi_watchdog.txt 2008-10-29 16:38:12.000000000 -0400 @@ -69,6 +69,11 @@ to the overall system performance. On x86 nmi_watchdog is disabled by default so you have to enable it with a boot time parameter. +It's possible to disable the NMI watchdog in run-time by writing "0" to +/proc/sys/kernel/nmi_watchdog. Writing "1" to the same file will re-enable +the NMI watchdog. Notice that you still need to use "nmi_watchdog=" parameter +in boot time. + NOTE: In kernels prior to 2.4.2-ac18 the NMI-oopser is enabled unconditionally on x86 SMP boxes. -- 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/