From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnout Vandecappelle Date: Thu, 05 Jun 2014 00:29:43 +0200 Subject: [Buildroot] [RFC/PATCH] linux: add external initramfs options In-Reply-To: <20140604204505.GA19703@arch.cereza> References: <1401138097-11024-1-git-send-email-guido@vanguardiasur.com.ar> <5386131B.6090809@mind.be> <20140604204505.GA19703@arch.cereza> Message-ID: <538F9DD7.6020102@mind.be> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net On 04/06/14 22:45, Ezequiel Garcia wrote: > Hello Arnout, > > On 28 May 06:47 PM, Arnout Vandecappelle wrote: > [..] >>> >>> The path specified can be a cpio archive or a directory, just like >>> the kernel config. The path is specified w.r.t. BRs topdir, and made >>> absolute since the kernel builds in another directory. >> >> This patch does nothing more than update the kernel config. Since you can >> already supply a custom kernel config, I don't think there is much added value >> to moving these options to the buildroot config. >> >> The only feature you add is that the patch can be relative to the buildroot >> directory. Not enough to be relevant, IMHO, especially since the patch adds >> non-negligible complexity. >> > > Our software stack includes a kernel with an appended initramfs to take care > of software upgrade and find, check and switch to the "real" rootfs. Both > the initramfs and rootfs are Buildroot-based, but each of them with their > own configuration and history (in separate git repos). > > Hence we came up with this solution: the initramfs would live in a different > repo, and after it's built we use this new option to append it in the kernel. > > Maybe you have a better idea, and there's a cleaner way to accomplish this > with Buildroot? Use a custom kernel config, and code the path to the external initramfs in that custom kernel config instead of in the buildroot config. You can use $(BASE_DIR)/../initramfs-output-dir if you want to avoid absolute paths in the config. Actually, in your case the easiest solution would be to build the kernel together with the initramfs-buildroot and use the initramfs rootfs instead of the cpio one. In the real-rootfs-buildroot you don't need to build a kernel. Or am I missing something? Regards, Arnout > > Thanks for the feedback! > -- Arnout Vandecappelle arnout at mind be Senior Embedded Software Architect +32-16-286500 Essensium/Mind http://www.mind.be G.Geenslaan 9, 3001 Leuven, Belgium BE 872 984 063 RPR Leuven LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle GPG fingerprint: 7CB5 E4CC 6C2E EFD4 6E3D A754 F963 ECAB 2450 2F1F