From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752457Ab1ASAYT (ORCPT ); Tue, 18 Jan 2011 19:24:19 -0500 Received: from mx1.redhat.com ([209.132.183.28]:53780 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751446Ab1ASAYS (ORCPT ); Tue, 18 Jan 2011 19:24:18 -0500 Date: Tue, 18 Jan 2011 19:23:40 -0500 From: Don Zickus To: Marcin Slusarz Cc: LKML , Stephane Eranian , Peter Zijlstra , Frederic Weisbecker , Ingo Molnar , stable@kernel.org Subject: Re: [PATCH 1/3] watchdog: fix broken nowatchdog logic Message-ID: <20110119002340.GB31465@redhat.com> References: <1295390266-9347-1-git-send-email-marcin.slusarz@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1295390266-9347-1-git-send-email-marcin.slusarz@gmail.com> User-Agent: Mutt/1.5.20 (2009-08-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jan 18, 2011 at 11:37:44PM +0100, Marcin Slusarz wrote: > Passing nowatchdog to kernel disables 2 things: creation of watchdog threads > AND initialization of percpu watchdog_hrtimer. As hrtimers are initialized > only at boot it's not possible to enable watchdog later - for me all watchdog > threads started to eat 100% of CPU time, but they could just crash. > > Additionally, even if these threads would start properly, > watchdog_disable_all_cpus was guarded by no_watchdog check, so you > couldn't disable watchdog. > > To fix this, remove no_watchdog variable and use already existing > watchdog_enabled variable. These three patches seem reasonable. I'll queue them up. Thanks, Don