From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from ozlabs.org ([203.10.76.45]) by canuck.infradead.org with esmtps (Exim 4.72 #1 (Red Hat Linux)) id 1PxInB-0003e5-Kg for kexec@lists.infradead.org; Wed, 09 Mar 2011 12:47:06 +0000 Date: Wed, 9 Mar 2011 23:46:57 +1100 From: Anton Blanchard Subject: Re: [PATCH 1/2] kdump: Allow shrinking of kdump region to be overridden Message-ID: <20110309234657.264d3080@kryten> In-Reply-To: <20110309122046.GC16951@cr0.redhat.com> References: <20100825002258.GD28360@kryten> <4D771EE6.5050404@linux.vnet.ibm.com> <20110309122046.GC16951@cr0.redhat.com> Mime-Version: 1.0 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: kexec-bounces@lists.infradead.org Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: =?ISO-8859-1?B?QW3pcmljbw==?= Wang Cc: Mahesh Jagannath Salgaonkar , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, "Eric W. Biederman" , akpm@linux-foundation.org Hi, > The crashkernel region is specified via kernel cmdline, so why > not just drop a failure when it overlaps with RMO region? > Am I missing something? Unfortunately a ppc64 kernel requires a chunk of RMO memory. We would need the ability to specify multiple crashkernel regions - about 32MB in the RMO and the rest can be anywhere. That sounds pretty fragile for a user to configure successfully on the cmdline. Thats why the ppc64 crashkernel region begins mid way through the RMO region. It means both kernels get a chunk of RMO and we only have to deal with one crashkernel reservation in all the tools and documentation. Anton _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Wed, 9 Mar 2011 23:46:57 +1100 From: Anton Blanchard To: =?ISO-8859-1?B?QW3pcmljbw==?= Wang Subject: Re: [PATCH 1/2] kdump: Allow shrinking of kdump region to be overridden Message-ID: <20110309234657.264d3080@kryten> In-Reply-To: <20110309122046.GC16951@cr0.redhat.com> References: <20100825002258.GD28360@kryten> <4D771EE6.5050404@linux.vnet.ibm.com> <20110309122046.GC16951@cr0.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Cc: Mahesh Jagannath Salgaonkar , kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, "Eric W. Biederman" , akpm@linux-foundation.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Hi, > The crashkernel region is specified via kernel cmdline, so why > not just drop a failure when it overlaps with RMO region? > Am I missing something? Unfortunately a ppc64 kernel requires a chunk of RMO memory. We would need the ability to specify multiple crashkernel regions - about 32MB in the RMO and the rest can be anywhere. That sounds pretty fragile for a user to configure successfully on the cmdline. Thats why the ppc64 crashkernel region begins mid way through the RMO region. It means both kernels get a chunk of RMO and we only have to deal with one crashkernel reservation in all the tools and documentation. Anton From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932314Ab1CIMrE (ORCPT ); Wed, 9 Mar 2011 07:47:04 -0500 Received: from ozlabs.org ([203.10.76.45]:50286 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932144Ab1CIMrB (ORCPT ); Wed, 9 Mar 2011 07:47:01 -0500 Date: Wed, 9 Mar 2011 23:46:57 +1100 From: Anton Blanchard To: =?ISO-8859-1?B?QW3pcmljbw==?= Wang Cc: Mahesh Jagannath Salgaonkar , "Eric W. Biederman" , akpm@linux-foundation.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org Subject: Re: [PATCH 1/2] kdump: Allow shrinking of kdump region to be overridden Message-ID: <20110309234657.264d3080@kryten> In-Reply-To: <20110309122046.GC16951@cr0.redhat.com> References: <20100825002258.GD28360@kryten> <4D771EE6.5050404@linux.vnet.ibm.com> <20110309122046.GC16951@cr0.redhat.com> X-Mailer: Claws Mail 3.7.6 (GTK+ 2.22.0; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, > The crashkernel region is specified via kernel cmdline, so why > not just drop a failure when it overlaps with RMO region? > Am I missing something? Unfortunately a ppc64 kernel requires a chunk of RMO memory. We would need the ability to specify multiple crashkernel regions - about 32MB in the RMO and the rest can be anywhere. That sounds pretty fragile for a user to configure successfully on the cmdline. Thats why the ppc64 crashkernel region begins mid way through the RMO region. It means both kernels get a chunk of RMO and we only have to deal with one crashkernel reservation in all the tools and documentation. Anton