From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760496AbYG2Wkx (ORCPT ); Tue, 29 Jul 2008 18:40:53 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756534AbYG2Wkn (ORCPT ); Tue, 29 Jul 2008 18:40:43 -0400 Received: from kirsty.vergenet.net ([202.4.237.240]:57809 "EHLO kirsty.vergenet.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755992AbYG2Wkm (ORCPT ); Tue, 29 Jul 2008 18:40:42 -0400 Date: Wed, 30 Jul 2008 08:40:41 +1000 From: Simon Horman To: Vivek Goyal Cc: kexec@lists.infradead.org, linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [patch 1/3] kdump: use is_kdump_kernel() in sba_init() Message-ID: <20080729224039.GE6370@verge.net.au> References: <20080729081235.293361145@vergenet.net> <20080729081629.356523305@vergenet.net> <20080729145156.GO25975@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20080729145156.GO25975@redhat.com> 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 On Tue, Jul 29, 2008 at 10:51:56AM -0400, Vivek Goyal wrote: > On Tue, Jul 29, 2008 at 06:12:36PM +1000, Simon Horman wrote: > > After recent patches* is_kdump_kernel() should return 1 in the > > case where code is executing in a crashkernel and 0 otherwise. > > It is save to use outside of CONFIG_KDUMP. > > > > * http://lkml.org/lkml/2008/7/28/445 > > > > Hi Simon, > > is_kdump_kernel() returns 1 when both the following conditions are true. > > - CONFIG_CRASH_DUMP is enabled > - And kernel is booting after a panic. > > If any of the above condition is not true, it returns 0. > > So for the cases where, CONFIG_CRASH_DUMP=n and kernel is booting after > panic, is_kdump_kernel() will still return 0. > > This essentially means that any kernel which is booting after a panic, > but does not have CONFIG_CRASH_DUMP enabled, will not take special actions > required for booting that kernel. Until, somebody can come up with another > usage of booting a kernel after a panic (apart from crash dump), I think > this is good enough an assumption. > > So your changes will work. I just wanted to clarify the semantics more > explicitly. Hi Vivek, sorry if my explanation was confused. The scheme that you describe above is what I am working with too. -- Horms