From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jason Gunthorpe Subject: Re: [Qemu-devel] Change of TEXT_OFFSET for multi_v7_defconfig Date: Tue, 22 Apr 2014 11:53:25 -0600 Message-ID: <20140422175325.GD23955@obsidianresearch.com> References: <534D0D91.8020406@linaro.org> <534EAD6C.3040502@codeaurora.org> <534EF153.5050603@codeaurora.org> <53501E87.6070307@codeaurora.org> <20140417203521.GB22411@obsidianresearch.com> <535681A4.1080402@monstr.eu> <20140422171141.GW24070@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from quartz.orcorp.ca ([184.70.90.242]:52038 "EHLO quartz.orcorp.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932927AbaDVRxi (ORCPT ); Tue, 22 Apr 2014 13:53:38 -0400 Content-Disposition: inline In-Reply-To: <20140422171141.GW24070@n2100.arm.linux.org.uk> Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: Russell King - ARM Linux Cc: Michal Simek , Nicolas Pitre , Peter Maydell , Daniel Thompson , Joel Fernandes , linux-arm-msm@vger.kernel.org, Stephen Boyd , Peter Crosthwaite , QEMU Developers , Christopher Covington , linux-arm-kernel@lists.infradead.org On Tue, Apr 22, 2014 at 06:11:42PM +0100, Russell King - ARM Linux wrote: > Put another way, if your platform is part of the multi-platform kernel > then you are *excluded* from being able to use this... unless you hack > the Kconfig, and then also provide a constant value for PHYS_OFFSET, > thereby _tying_ the kernel you built to a _single_ platform. That is exactly right. To get a fixed LMA you must commit to a non-relocatable kernel image. Realistically this patch would need to be accompanied by something that makes ARM_PATCH_PHYS_VIRT optional for multiplatform based on EXPERT or similar. The best usecase seems to be to support ELF tooling for low level debugging activities, a non-relocatable image isn't a blocker for that case. Since the patch is a no-op if LOAD_OFFSET isn't set, is there a downside I don't see? Thanks, Jason