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=-15.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SIGNED_OFF_BY,SPF_HELO_NONE,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 BDF6DC433E0 for ; Thu, 18 Jun 2020 01:32:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 953272222C for ; Thu, 18 Jun 2020 01:32:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592443972; bh=YPvB/UVTTNOlO5+VGInzT9x0BmqbR/P5AtA7zUkZ0g0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QpWBIi+K+Aw+W2bt1mDLripfVpQKn29ivJb0PvKQQjkGJGEMhr/Qt/W9DkBIPSGO/ /8HjfxLtx3W546GKksiiZEtSdjORo88WoPWQbc811t+WGi1KMwEjw0YuQNmABXUQPu 2adpN8aY9nAI7vWBALRzFh+VAABms+OrCoiwWGww= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732896AbgFRBcv (ORCPT ); Wed, 17 Jun 2020 21:32:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:39724 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732426AbgFRB37 (ORCPT ); Wed, 17 Jun 2020 21:29:59 -0400 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 A352522228; Thu, 18 Jun 2020 01:29:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592443799; bh=YPvB/UVTTNOlO5+VGInzT9x0BmqbR/P5AtA7zUkZ0g0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vx3yFd0Pm6gKeVpsgb8+79y0P0wy0+gselx8gvCGMTnnSF61vyOdpFlCSweYw4d4k /gUDAMA/cCwpSh8q+dUzPxCSSNC3aP3dfc+t399yha3bZe3dgGMBlksiDV7C7SZ/pp NdWCsHW047Onyia9hB4BRX31kJfaq2PBL4DXOjME= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Nick Desaulniers , Andrew Morton , Nathan Chancellor , Fangrui Song , Jeremy Fitzhardinge , Thomas Gleixner , Vincenzo Frascino , Ilie Halip , Linus Torvalds , Sasha Levin , clang-built-linux@googlegroups.com Subject: [PATCH AUTOSEL 4.9 77/80] elfnote: mark all .note sections SHF_ALLOC Date: Wed, 17 Jun 2020 21:28:16 -0400 Message-Id: <20200618012819.609778-77-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200618012819.609778-1-sashal@kernel.org> References: <20200618012819.609778-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Nick Desaulniers [ Upstream commit 51da9dfb7f20911ae4e79e9b412a9c2d4c373d4b ] ELFNOTE_START allows callers to specify flags for .pushsection assembler directives. All callsites but ELF_NOTE use "a" for SHF_ALLOC. For vdso's that explicitly use ELF_NOTE_START and BUILD_SALT, the same section is specified twice after preprocessing, once with "a" flag, once without. Example: .pushsection .note.Linux, "a", @note ; .pushsection .note.Linux, "", @note ; While GNU as allows this ordering, it warns for the opposite ordering, making these directives position dependent. We'd prefer not to precisely match this behavior in Clang's integrated assembler. Instead, the non __ASSEMBLY__ definition of ELF_NOTE uses __attribute__((section(".note.Linux"))) which is created with SHF_ALLOC, so let's make the __ASSEMBLY__ definition of ELF_NOTE consistent with C and just always use "a" flag. This allows Clang to assemble a working mainline (5.6) kernel via: $ make CC=clang AS=clang Signed-off-by: Nick Desaulniers Signed-off-by: Andrew Morton Reviewed-by: Nathan Chancellor Reviewed-by: Fangrui Song Cc: Jeremy Fitzhardinge Cc: Thomas Gleixner Cc: Vincenzo Frascino Link: https://github.com/ClangBuiltLinux/linux/issues/913 Link: http://lkml.kernel.org/r/20200325231250.99205-1-ndesaulniers@google.com Debugged-by: Ilie Halip Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- include/linux/elfnote.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/include/linux/elfnote.h b/include/linux/elfnote.h index 278e3ef05336..56c6d9031663 100644 --- a/include/linux/elfnote.h +++ b/include/linux/elfnote.h @@ -53,7 +53,7 @@ .popsection ; #define ELFNOTE(name, type, desc) \ - ELFNOTE_START(name, type, "") \ + ELFNOTE_START(name, type, "a") \ desc ; \ ELFNOTE_END -- 2.25.1