From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762009AbXGQDvU (ORCPT ); Mon, 16 Jul 2007 23:51:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757243AbXGQDvJ (ORCPT ); Mon, 16 Jul 2007 23:51:09 -0400 Received: from e2.ny.us.ibm.com ([32.97.182.142]:54355 "EHLO e2.ny.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757192AbXGQDvI (ORCPT ); Mon, 16 Jul 2007 23:51:08 -0400 Date: Tue, 17 Jul 2007 09:20:55 +0530 From: Vivek Goyal To: kexec@lists.infradead.org, linux-kernel@vger.kernel.org Cc: "Ken'ichi Ohmichi" Subject: Re: Determine version of kernel that produced vmcore Message-ID: <20070717035055.GA4869@in.ibm.com> Reply-To: vgoyal@in.ibm.com References: <20070710120243.GA10121@hmsendeavour.rdu.redhat.com> <20070713200533oomichi@mail.jp.nec.com> <20070713131550.GB10985@suse.de> <20070716041918.GA11390@in.ibm.com> <20070716115707.GA29923@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070716115707.GA29923@suse.de> User-Agent: Mutt/1.5.11 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Jul 16, 2007 at 01:57:07PM +0200, Bernhard Walle wrote: > * Vivek Goyal [2007-07-16 06:19]: > > On Fri, Jul 13, 2007 at 03:15:50PM +0200, Bernhard Walle wrote: > > > * Ken'ichi Ohmichi [2007-07-13 13:05]: > > > > > > > > BTW, I'd like to remove PAGESIZE from a mkdfinfo file. > > > > While 2nd-kernel is running, new makedumpfile comes to consider > > > > 2nd-kernel PAGESIZE as 1st-kernel PAGESIZE without getting PAGESIZE > > > > from a mkdfinfo file. > > > > > > I don't think that's a good idea. IMO the kernel should be modified to > > > export the page size in a variable for that purpose. That would solve > > > all problems and dependencies, doesn't it? > > > > > > > Agreed. We need to export PAGESIZE from kernel instead of assuming that > > second kernel as got same page size as first kernel. > > So what about this? Do you think it has a chance to get included? > Should the variable not be inside mm/ but otherwhere? > > > Signed-off-by: Bernhard Walle > > --- > mm/mmap.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > --- a/mm/mmap.c > +++ b/mm/mmap.c > @@ -35,6 +35,16 @@ > #define arch_mmap_check(addr, len, flags) (0) > #endif > > +#ifdef CONFIG_KEXEC > + > +/* > + * Although that variable is not needed for the kernel, initialise it here > + * to have the page size available in the vmlinux binary. > + */ > +int page_size = PAGE_SIZE; > + Thinking more about it. These config variables are accessible in user space in first kernel through sysconf() interface. In that case kexec can pack required config variables into an ELF note and kernel does not have to intervene. Thanks Vivek