Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934573AbaFSU5J (ORCPT ); Thu, 19 Jun 2014 16:57:09 -0400 Received: from mail-pb0-f53.google.com ([209.85.160.53]:58208 "EHLO mail-pb0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932343AbaFSU5E (ORCPT ); Thu, 19 Jun 2014 16:57:04 -0400 From: Kevin Hilman To: Nicolas Pitre Cc: Stephen Boyd , Taras Kondratiuk , Thomas Petazzoni , Russell King , Jason Cooper , Victor Kamensky , LKML , Ben Dooks , Olof Johansson , Linaro Networking , linux-arm-kernel Subject: Re: [PATCH] ARM: zImage: ensure header in LE format for BE8 kernels References: <1397147232-28516-1-git-send-email-taras.kondratiuk@linaro.org> <53A1D701.8060404@codeaurora.org> <53A1D8FE.6030404@codeaurora.org> <7hk38cycuh.fsf@paris.lan> Date: Thu, 19 Jun 2014 13:57:01 -0700 In-Reply-To: (Nicolas Pitre's message of "Thu, 19 Jun 2014 16:32:12 -0400 (EDT)") Message-ID: <7hk38cvcrm.fsf@paris.lan> User-Agent: Gnus/5.130008 (Ma Gnus v0.8) Emacs/24.3 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Nicolas Pitre writes: > On Thu, 19 Jun 2014, Kevin Hilman wrote: > >> I think this should probably be officialized since we've taken away the >> ability for magic-number checking tools (like 'file') to distinguish >> between big- and little-endian zImages. >> >> For now, I've updated my tools to check for 'setend be' in ARM and >> Thumb2 mode, but if this does get officialized, I'll gladly move over to >> it. > > Would you ACK this patch? > > ----- >8 > ARM: zImage: identify kernel endianness > > With patch #8067/1 applied, it is no longer possible to determine the minor nit: I'd rather see a commit id (commit subject) instead of the reference in RMK's patch tracker, but other than that... > endianness of a compiled kernel image. This normally shouldn't matter > to the boot environment, except for those cases where the selection of > a ramdisk or root filesystem with a matching endianness has to be > automated. > > Let's add a flag to the zImage header indicating the actual endianness. > Four bytes from offset 0x30 can be interpreted as follows: > > 04 03 02 01 big endian kernel > > 01 02 03 04 little endian kernel > > Anything else should be interpreted as "unknown", in which case it is > most likely that patch #8067/1 was not applied either and the zImage > magic number at offset 0x24 could be used instead to determine > endianness. No zImage before this patch ever produced 0x01020304 nor > 0x04030201 at offset 0x30 so there is no confusion possible. > > Signed-off-by: Nicolas Pitre Acked-by: Kevin Hilman -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/