From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753114Ab1HBJv2 (ORCPT ); Tue, 2 Aug 2011 05:51:28 -0400 Received: from mtagate7.uk.ibm.com ([194.196.100.167]:43724 "EHLO mtagate7.uk.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752512Ab1HBJvW (ORCPT ); Tue, 2 Aug 2011 05:51:22 -0400 Subject: Re: [patch v2 01/10] kdump: Add KEXEC_CRASH_CONTROL_MEMORY_LIMIT From: Michael Holzheu Reply-To: holzheu@linux.vnet.ibm.com To: Vivek Goyal Cc: ebiederm@xmission.com, mahesh@linux.vnet.ibm.com, hbabu@us.ibm.com, oomichi@mxs.nes.nec.co.jp, horms@verge.net.au, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org In-Reply-To: <20110801201644.GG3805@redhat.com> References: <20110727125504.491183728@linux.vnet.ibm.com> <20110727125807.529303146@linux.vnet.ibm.com> <20110801201644.GG3805@redhat.com> Content-Type: text/plain; charset="UTF-8" Organization: IBM Date: Tue, 02 Aug 2011 11:51:04 +0200 Message-ID: <1312278664.4881.35.camel@br98xy6r> Mime-Version: 1.0 X-Mailer: Evolution 2.32.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello Vivek, On Mon, 2011-08-01 at 16:16 -0400, Vivek Goyal wrote: > On Wed, Jul 27, 2011 at 02:55:05PM +0200, Michael Holzheu wrote: > > From: Michael Holzheu > > > > On s390 there is a different KEXEC_CONTROL_MEMORY_LIMIT for the normal and > > the kdump kexec case. Therefore this patch introduces a new macro > > KEXEC_CRASH_CONTROL_MEMORY_LIMIT. This is set to > > KEXEC_CONTROL_MEMORY_LIMIT for all architectures that do not define > > KEXEC_CRASH_CONTROL_MEMORY_LIMIT. > > Hi Michael, > > Curious that why limit is different for kexec and kdump cases on s390 > only. The standard kexec relocate_kernel code calls a machine instruction that must run below 2 GiB. For kdump we currently do not use the control page at all because no segments have to be moved in that case. Perhaps I am still missing something here? Michael