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=-19.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 4E2D9C43460 for ; Sun, 2 May 2021 14:10:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2B3D161208 for ; Sun, 2 May 2021 14:10:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233039AbhEBOLG (ORCPT ); Sun, 2 May 2021 10:11:06 -0400 Received: from mail.kernel.org ([198.145.29.99]:51246 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232151AbhEBOH6 (ORCPT ); Sun, 2 May 2021 10:07:58 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 0554F613CA; Sun, 2 May 2021 14:06:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1619964389; bh=6BL5n9GXke5xzYz4gBTpXlo5ncC3qECojOQv0ChdGaM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=de6LUnVTgQKAlL1y4ll4A11V2/I7ByYrmcQveh5b2KxE38gQWUyV1tWAZiYEqNJzE tttlI/0nZlyObXAn6FirsdG+fQgFd0b42hdTyaoxrGH68EJy6qHh2zAEzADXeGSbaZ ZyJNWheXm7oTve50URYurckIk/WE1/zBMip0RUDKAASOBATtjHP9fqj8uX9Q39jxBS QpPKaeYp/voAk4l+kazCoqeTEfDhVNz5WSUZv6lPOXz7/L3wgpan2sHIy9bykwYQ13 M6T+vSdZWTzjxkUSLaMiTvQNI3mlPVIVy94VS97yYi9j4keGRbeVQQqrnWW9MzhiJm 3hEtoPvtWEa0A== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: John Millikin , Nathan Chancellor , Borislav Petkov , Ard Biesheuvel , Sedat Dilek , Sasha Levin , clang-built-linux@googlegroups.com Subject: [PATCH AUTOSEL 4.4 04/10] x86/build: Propagate $(CLANG_FLAGS) to $(REALMODE_FLAGS) Date: Sun, 2 May 2021 10:06:16 -0400 Message-Id: <20210502140623.2720479-4-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210502140623.2720479-1-sashal@kernel.org> References: <20210502140623.2720479-1-sashal@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: John Millikin [ Upstream commit 8abe7fc26ad8f28bfdf78adbed56acd1fa93f82d ] When cross-compiling with Clang, the `$(CLANG_FLAGS)' variable contains additional flags needed to build C and assembly sources for the target platform. Normally this variable is automatically included in `$(KBUILD_CFLAGS)' via the top-level Makefile. The x86 real-mode makefile builds `$(REALMODE_CFLAGS)' from a plain assignment and therefore drops the Clang flags. This causes Clang to not recognize x86-specific assembler directives:   arch/x86/realmode/rm/header.S:36:1: error: unknown directive   .type real_mode_header STT_OBJECT ; .size real_mode_header, .-real_mode_header   ^ Explicit propagation of `$(CLANG_FLAGS)' to `$(REALMODE_CFLAGS)', which is inherited by real-mode make rules, fixes cross-compilation with Clang for x86 targets. Relevant flags: * `--target' sets the target architecture when cross-compiling. This   flag must be set for both compilation and assembly (`KBUILD_AFLAGS')   to support architecture-specific assembler directives. * `-no-integrated-as' tells clang to assemble with GNU Assembler   instead of its built-in LLVM assembler. This flag is set by default   unless `LLVM_IAS=1' is set, because the LLVM assembler can't yet   parse certain GNU extensions. Signed-off-by: John Millikin Signed-off-by: Nathan Chancellor Signed-off-by: Borislav Petkov Acked-by: Ard Biesheuvel Tested-by: Sedat Dilek Link: https://lkml.kernel.org/r/20210326000435.4785-2-nathan@kernel.org Signed-off-by: Sasha Levin --- arch/x86/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 2b3adb3008c3..c0045e3ad0f5 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -40,6 +40,7 @@ REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -ffreestanding REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -fno-stack-protector) REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), -Wno-address-of-packed-member) REALMODE_CFLAGS += $(call __cc-option, $(CC), $(REALMODE_CFLAGS), $(cc_stack_align4)) +REALMODE_CFLAGS += $(CLANG_FLAGS) export REALMODE_CFLAGS # BITS is used as extension for files which are available in a 32 bit -- 2.30.2