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=unavailable 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 9BA85C433E2 for ; Thu, 18 Jun 2020 01:35:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 794FD221F8 for ; Thu, 18 Jun 2020 01:35:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592444151; bh=eJRf/DLe3SoTgQ+rYReWSmo1n75LlOi6Lxrz7lpF1ys=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=y6A449G7dWdUW3XVss9xg2wkMpSr3pglKpgwGaR9fpNWoIs98Tt6gUuFsiCAxEI4j d9VL9EzQrJba2Daj0JYviT2PU4sN34Qk40hmDMseZSJwsRgJ2iP6kD30ncZaIF+nQt ja+tr+9Ul/3VZuy7HInQiGYaUkCJ4eHsqKbydXLQ= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732751AbgFRBbT (ORCPT ); Wed, 17 Jun 2020 21:31:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:36606 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732027AbgFRB2H (ORCPT ); Wed, 17 Jun 2020 21:28:07 -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 09702221F3; Thu, 18 Jun 2020 01:28:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592443686; bh=eJRf/DLe3SoTgQ+rYReWSmo1n75LlOi6Lxrz7lpF1ys=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=gqw9zfcyEBnJr93X2YAXkUEsRBcrEy8WIFVbwqTyPWPYiBzlcLyl6hNlTnWqup4pU ksBj6lCuHqb26kywPBZvHe5ea9HhQyH4TnlX8T4SRYL8Z7e4XLfOSn5LfqsaUTU8UH uT4jRuKO5QJjfsWdXy+1knEMQ5doZgQ+VRz8WjwU= 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 4.14 099/108] elfnote: mark all .note sections SHF_ALLOC Date: Wed, 17 Jun 2020 21:25:51 -0400 Message-Id: <20200618012600.608744-99-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200618012600.608744-1-sashal@kernel.org> References: <20200618012600.608744-1-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 f236f5b931b2..7fdd7f355b52 100644 --- a/include/linux/elfnote.h +++ b/include/linux/elfnote.h @@ -54,7 +54,7 @@ .popsection ; #define ELFNOTE(name, type, desc) \ - ELFNOTE_START(name, type, "") \ + ELFNOTE_START(name, type, "a") \ desc ; \ ELFNOTE_END -- 2.25.1