From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763492AbXGZPeu (ORCPT ); Thu, 26 Jul 2007 11:34:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755158AbXGZPen (ORCPT ); Thu, 26 Jul 2007 11:34:43 -0400 Received: from mx1.suse.de ([195.135.220.2]:59954 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752088AbXGZPem (ORCPT ); Thu, 26 Jul 2007 11:34:42 -0400 Date: Thu, 26 Jul 2007 17:34:40 +0200 From: Bernhard Walle To: Vivek Goyal Cc: Takenori Nagano , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, k-miyoshi@cb.jp.nec.com, Andrew Morton Subject: Re: [patch] add kdump_after_notifier Message-ID: <20070726153440.GA19095@suse.de> Mail-Followup-To: Vivek Goyal , Takenori Nagano , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, k-miyoshi@cb.jp.nec.com, Andrew Morton References: <469F55D0.4050203@ah.jp.nec.com> <20070726140702.GA8949@suse.de> <20070726153240.GA15969@in.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070726153240.GA15969@in.ibm.com> Organization: SUSE LINUX Products GmbH User-Agent: Mutt/1.5.16 (2007-06-09) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org * Vivek Goyal [2007-07-26 17:32]: > On Thu, Jul 26, 2007 at 04:07:02PM +0200, Bernhard Walle wrote: > > * Takenori Nagano [2007-07-19 14:15]: > > > > > > In latest kernel, we can't use panic_notifier_list if kdump is enabled. > > > panic_notifier_list is very useful function for debug, failover, etc... > > > > > > So this patch adds a control file /proc/sys/kernel/dump_after_notifier > > > and resolves a problem users can not use both kdump and panic_notifier_list > > > at the same time. > > > > > > kdump_after_notifier = 0 > > > -> panic() > > > -> crash_kexec(NULL) > > > > > > kdump_after_notifier = 1 > > > -> panic() > > > -> atomic_notifier_call_chain(&panic_notifier_list, 0, buf); > > > -> crash_kexec(NULL) > > > > What's problematic about this patch? I also would like to see that > > feature. > > I would like to see the code which will get executed after panic and > before crash_kexec(). This potentially makes crash dump feature unreliable > in the sense one can now register on panic_notifier_list and try to > do whole lot of things and might get stuck there. After the system > has crashed, one is not supposed to do a whole lot. Of course, but that's why the patch doesn't change this by default but gives the user the choice. Thanks, Bernhard