From patchwork Sun Nov 4 13:52:27 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sasha Levin X-Patchwork-Id: 150120 Delivered-To: patch@linaro.org Received: by 2002:a2e:299d:0:0:0:0:0 with SMTP id p29-v6csp1545719ljp; Sun, 4 Nov 2018 06:02:24 -0800 (PST) X-Google-Smtp-Source: AJdET5cJCXZR/CPS6OC3Fk83wvoxfSSJpWuSUmki9rR9Mwio2ZGqQer+nLaDCkuYO3Rw2kt4PdAy X-Received: by 2002:a62:9109:: with SMTP id l9-v6mr18581079pfe.154.1541340143968; Sun, 04 Nov 2018 06:02:23 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1541340143; cv=none; d=google.com; s=arc-20160816; b=Aips07dMzL5UX3+viMBAvMKRmw+VZXAVTfnz1Vvz15qFRL/EpmE6nWtuM+LYlCNvlt 5P+D+NTW43Rx8O/dmvm8PWyNFQmz1iZfRlYeF7V7tmgTSkOpvvdGTqg2JH1GZJb52ysm HxPq7Azmesm0uO1dd3JuKoWUTTN026WNNL5EqObO3WcfL4UAFYlBMcdAAUXOwuh89a7K pVDeZbatFDV73qFbVYP5eaCb1RRA8S/8ujg7ix5KLENiOGekPbbhMCKPOzgoew1VdcC6 +V8hGFYJ1GTfvZVY23Kyh7JAHWspnNv1yh2r2WE7JRimgT7bY9Bdnt0DRpRGg3yokvd0 SvTg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature; bh=7oXcIrqtSmuyBPYUG1e+EHqqso2pIJMI76WGppdfM4s=; b=ESApVUXCBFOJwo6/AZLa+KiS/k+tKqDTjqNeg+bu69Ylp06dKfDGBN39rI4uOk7Gon jl3cDYD0ijJCtVhUsaYGL5o88lPUQLnZeYnP6M0MNCnWK3NElxY4hR9J1xV8Vl0Glp5a Dh8s3EPs3nOMMO1ONbYsrqt9j3w/zCIK7f1Zshx7LXBumNirjgpBhy9XCKAGEy+XNDEt WXSl8p4nwqPDXcj7tqx7EXt4aBzmS4SgobUGagmcCRtT40KBmHl24ZO3Ebk5g3d3HYfg vLnpSXYzo9lVEt33sA/qFHG1DL8vqTtkT4gFIUrFvLrfRN6RM3tvHN0r/88ogpq4kBNp FJ2g== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=XN4m8VJx; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id v10si10915652pgg.510.2018.11.04.06.02.23; Sun, 04 Nov 2018 06:02:23 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=XN4m8VJx; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731648AbeKDXR2 (ORCPT + 32 others); Sun, 4 Nov 2018 18:17:28 -0500 Received: from mail.kernel.org ([198.145.29.99]:46858 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730941AbeKDXIR (ORCPT ); Sun, 4 Nov 2018 18:08:17 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 247D120869; Sun, 4 Nov 2018 13:53:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541339593; bh=M+nlvSSWJ6LODF+My80H6Ek0nsvcQgbQobsSHZ3QULs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XN4m8VJxfqJL9aTy//G86LiZ9DVqINJrXXIaSjOvMe7mlpdz6K4veWMFQhUTmJFHm x0nfkW8LB88CfIRdeNj5Lz0099MVyEEzfoas1uoL40qbeMBks/dY42aCNSMbk7SFjl jOIUAKhl1+sS4qOcLVRlDmP1QmcW2kRCbiUrHwX8= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Joel Stanley , Michael Ellerman , Sasha Levin Subject: [PATCH AUTOSEL 4.18 32/45] powerpc/boot: Ensure _zimage_start is a weak symbol Date: Sun, 4 Nov 2018 08:52:27 -0500 Message-Id: <20181104135240.88431-32-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181104135240.88431-1-sashal@kernel.org> References: <20181104135240.88431-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 --- arch/powerpc/boot/crt0.S | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) -- 2.17.1 diff --git a/arch/powerpc/boot/crt0.S b/arch/powerpc/boot/crt0.S index dcf2f15e6797..32dfe6d083f3 100644 --- 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: