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=-7.5 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 36C00C43441 for ; Mon, 19 Nov 2018 17:44:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F15F92145D for ; Mon, 19 Nov 2018 17:44:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="SQ11mLvc" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F15F92145D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389470AbeKTEIn (ORCPT ); Mon, 19 Nov 2018 23:08:43 -0500 Received: from mail.kernel.org ([198.145.29.99]:47444 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389079AbeKTDLd (ORCPT ); Mon, 19 Nov 2018 22:11:33 -0500 Received: from localhost (5356596B.cm-6-7b.dynamic.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id ED220206BA; Mon, 19 Nov 2018 16:47:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1542646041; bh=V2SYX45sBKNRoyMzRISjVEbEKcPanUJIldz+FsnAAYc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SQ11mLvc4ujAR1hK/qsf0C5rbtcEztHM405mIk2TcnPC63A/KiAhEfwevJUiW9zFR syS2etddxxZWRRAaM95DRM0cM8NSmiWycxWWQS4HkerI9rMxAUl5i+7iT8nVIT5kLZ ZEDuy3uzoAXQl3pNJZ97npChfMl2DzXUZyMdW8Ik= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Joel Stanley , Nick Desaulniers , Michael Ellerman , Sasha Levin Subject: [PATCH 4.14 014/124] powerpc/boot: Ensure _zimage_start is a weak symbol Date: Mon, 19 Nov 2018 17:27:48 +0100 Message-Id: <20181119162615.681510668@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181119162612.951907286@linuxfoundation.org> References: <20181119162612.951907286@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Joel Stanley [ Upstream commit ee9d21b3b3583712029a0db65a4b7c081d08d3b3 ] When building with clang crt0's _zimage_start is not marked weak, which breaks the build when linking the kernel image: $ objdump -t arch/powerpc/boot/crt0.o |grep _zimage_start$ 0000000000000058 g .text 0000000000000000 _zimage_start ld: arch/powerpc/boot/wrapper.a(crt0.o): in function '_zimage_start': (.text+0x58): multiple definition of '_zimage_start'; arch/powerpc/boot/pseries-head.o:(.text+0x0): first defined here Clang requires the .weak directive to appear after the symbol is declared. The binutils manual says: This directive sets the weak attribute on the comma separated list of symbol names. If the symbols do not already exist, they will be created. So it appears this is different with clang. The only reference I could see for this was an OpenBSD mailing list post[1]. Changing it to be after the declaration fixes building with Clang, and still works with GCC. $ objdump -t arch/powerpc/boot/crt0.o |grep _zimage_start$ 0000000000000058 w .text 0000000000000000 _zimage_start Reported to clang as https://bugs.llvm.org/show_bug.cgi?id=38921 [1] https://groups.google.com/forum/#!topic/fa.openbsd.tech/PAgKKen2YCY Signed-off-by: Joel Stanley Reviewed-by: Nick Desaulniers Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/boot/crt0.S | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/arch/powerpc/boot/crt0.S +++ b/arch/powerpc/boot/crt0.S @@ -47,8 +47,10 @@ p_end: .long _end p_pstack: .long _platform_stack_top #endif - .weak _zimage_start .globl _zimage_start + /* Clang appears to require the .weak directive to be after the symbol + * is defined. See https://bugs.llvm.org/show_bug.cgi?id=38921 */ + .weak _zimage_start _zimage_start: .globl _zimage_start_lib _zimage_start_lib: