From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8F64C433DB for ; Mon, 28 Dec 2020 22:58:30 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AB1CE222BB for ; Mon, 28 Dec 2020 22:58:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728322AbgL1W4a (ORCPT ); Mon, 28 Dec 2020 17:56:30 -0500 Received: from elvis.franken.de ([193.175.24.41]:43952 "EHLO elvis.franken.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729632AbgL1W0V (ORCPT ); Mon, 28 Dec 2020 17:26:21 -0500 Received: from uucp (helo=alpha) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1ku0xP-00069Q-00; Mon, 28 Dec 2020 23:25:39 +0100 Received: by alpha.franken.de (Postfix, from userid 1000) id 8475EC05C4; Mon, 28 Dec 2020 23:25:32 +0100 (CET) Date: Mon, 28 Dec 2020 23:25:32 +0100 From: Thomas Bogendoerfer To: Paul Cercueil Cc: Nathan Chancellor , Nick Desaulniers , od@zcrc.me, linux-mips@vger.kernel.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, stable@vger.kernel.org Subject: Re: [PATCH] MIPS: boot: Fix unaligned access with CONFIG_MIPS_RAW_APPENDED_DTB Message-ID: <20201228222532.GA24926@alpha.franken.de> References: <20201216233956.280068-1-paul@crapouillou.net> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20201216233956.280068-1-paul@crapouillou.net> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Dec 16, 2020 at 11:39:56PM +0000, Paul Cercueil wrote: > The compressed payload is not necesarily 4-byte aligned, at least when > compiling with Clang. In that case, the 4-byte value appended to the > compressed payload that corresponds to the uncompressed kernel image > size must be read using get_unaligned_le(). > > This fixes Clang-built kernels not booting on MIPS (tested on a Ingenic > JZ4770 board). > > Fixes: b8f54f2cde78 ("MIPS: ZBOOT: copy appended dtb to the end of the kernel") > Cc: # v4.7 > Signed-off-by: Paul Cercueil > --- > arch/mips/boot/compressed/decompress.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/mips/boot/compressed/decompress.c b/arch/mips/boot/compressed/decompress.c > index c61c641674e6..47c07990432b 100644 > --- a/arch/mips/boot/compressed/decompress.c > +++ b/arch/mips/boot/compressed/decompress.c > @@ -117,7 +117,7 @@ void decompress_kernel(unsigned long boot_heap_start) > dtb_size = fdt_totalsize((void *)&__appended_dtb); > > /* last four bytes is always image size in little endian */ > - image_size = le32_to_cpup((void *)&__image_end - 4); > + image_size = get_unaligned_le32((void *)&__image_end - 4); gives me following error arch/mips/boot/compressed/decompress.c:120:16: error: implicit declaration of function ‘get_unaligned_le32’ [-Werror=implicit-function-declaration] image_size = get_unaligned_le32((void *)&__image_end - 4); I've added #include which fixes the compile error, but I'm wondering why the patch compiled for you ? Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessarily a good idea. [ RFC1925, 2.3 ]