From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757059Ab3DXPVP (ORCPT ); Wed, 24 Apr 2013 11:21:15 -0400 Received: from mail.active-venture.com ([67.228.131.205]:63777 "EHLO mail.active-venture.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756811Ab3DXPVL (ORCPT ); Wed, 24 Apr 2013 11:21:11 -0400 X-Originating-IP: 108.223.40.66 Date: Wed, 24 Apr 2013 08:21:42 -0700 From: Guenter Roeck To: Don Zickus Cc: "Eric W. Biederman" , linux-watchdog@vger.kernel.org, kexec@lists.infradead.org, wim@iguana.be, LKML , vgoyal@redhat.com, dyoung@redhat.com Subject: Re: [PATCH v3] watchdog: Add hook for kicking in kdump path Message-ID: <20130424152142.GA26864@roeck-us.net> References: <1366233596-34681-1-git-send-email-dzickus@redhat.com> <87li8gaku0.fsf@xmission.com> <20130418130009.GH79013@redhat.com> <20130418134904.GC2767@roeck-us.net> <20130418135257.GL79013@redhat.com> <20130418145413.GA1980@roeck-us.net> <20130424144226.GI79013@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130424144226.GI79013@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 24, 2013 at 10:42:26AM -0400, Don Zickus wrote: > On Thu, Apr 18, 2013 at 07:54:13AM -0700, Guenter Roeck wrote: > > > No, that will probably work. It is my misunderstanding. Is there a > > > common way to check the timeout length and the ping frequency? > > > > > Usually it is configured in /etc/watchdog.conf if the watchdog package > > is installed. The standard ping interval is "interval", the timeout is > > "watchdog-timeout". See "man watchdog.conf" for details. > > > > Minimum and maximum values for a given watchdog driver are not exported > > to user space, so you would have to look into the driver sources to find > > out what they are. > > Hi Guenter, > > Is there an easy way to determine which driver is loaded for each > /dev/watchdogN device (from a script perspective). > > Basically, I wanted to determine the module that needs to be included in > the kdump initrd image. > Sometimes. For example, the iTCO_wdt driver has an entry in /sys/devices, and /sys/class/watchdog/watchdogX/device points to it. That is not always the case, howewver. In my system, for example, the MEI watchdog is active, but there is nothing I can find that would give me an indication that /dev/watchdog0 actually points to the MEI watchdog driver. Of course I might be missing something, and there might be some other means to identify the driver from userspace. Would be great, actually, as I am having the same problem. Guenter