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=-24.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,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 4FD52C433DB for ; Tue, 9 Feb 2021 00:59:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E95FF64E82 for ; Tue, 9 Feb 2021 00:59:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230023AbhBIA70 (ORCPT ); Mon, 8 Feb 2021 19:59:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:42504 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229621AbhBIA7X (ORCPT ); Mon, 8 Feb 2021 19:59:23 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id E556464E82; Tue, 9 Feb 2021 00:58:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612832322; bh=WTzVfyDECWyda2V3zd0/237OY1tpljp4GOvC63bQyIA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=PrAK/jQGItiwbV2qgsJ/REd2PxX8xY0hxWCzpJ3g0zw3C1P3nAfuoc3weeFg+S562 c/Tx5gj0cke5MV99TYssKctfV4Yx9uo4aGiLToBUr3qdM7cVEj2NnHTCvwzGkMh0lm LKUBTqqbELpeKa3KZisgPSxCJhSIJkqmjOisV1+RrIqntXGGj2+VbHyqE+jT7o4evI vesnTcCAlTdyadlWcrGug31us/UhtHq9CYXbYdp0CO+wzpSD1nRteVZdKmi+Ehcoyo emavb04ynMAQAAmN9+GabfUnnpYhTeCjvHUbI2nYQUHcXkN/WafFyEzAIXFV4uL+AY i88GixNIhfw/A== From: Nathan Chancellor To: Catalin Marinas , Will Deacon Cc: Nick Desaulniers , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, Nathan Chancellor , Arnd Bergmann Subject: [PATCH v2] arm64: Make CPU_BIG_ENDIAN depend on ld.bfd or ld.lld 13.0.0+ Date: Mon, 8 Feb 2021 17:57:20 -0700 Message-Id: <20210209005719.803608-1-nathan@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210202022441.1451389-1-nathan@kernel.org> References: <20210202022441.1451389-1-nathan@kernel.org> MIME-Version: 1.0 X-Patchwork-Bot: notify Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Similar to commit 28187dc8ebd9 ("ARM: 9025/1: Kconfig: CPU_BIG_ENDIAN depends on !LD_IS_LLD"), ld.lld prior to 13.0.0 does not properly support aarch64 big endian, leading to the following build error when CONFIG_CPU_BIG_ENDIAN is selected: ld.lld: error: unknown emulation: aarch64linuxb This has been resolved in LLVM 13. To avoid errors like this, only allow CONFIG_CPU_BIG_ENDIAN to be selected if using ld.bfd or ld.lld 13.0.0 and newer. While we are here, the indentation of this symbol used spaces since its introduction in commit a872013d6d03 ("arm64: kconfig: allow CPU_BIG_ENDIAN to be selected"). Change it to tabs to be consistent with kernel coding style. Link: https://github.com/ClangBuiltLinux/linux/issues/380 Link: https://github.com/ClangBuiltLinux/linux/issues/1288 Link: https://github.com/llvm/llvm-project/commit/7605a9a009b5fa3bdac07e3131c8d82f6d08feb7 Link: https://github.com/llvm/llvm-project/commit/eea34aae2e74e9b6fbdd5b95f479bc7f397bf387 Reported-by: Arnd Bergmann Signed-off-by: Nathan Chancellor --- v1 -> v2: * Conditionally disable CONFIG_CPU_BIG_ENDIAN for older versions of ld.lld now that proper support has been added to ld.lld 13+ (thanks to the quick work of Fangrui Song). arch/arm64/Kconfig | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index f39568b28ec1..912da4e2ab59 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -952,8 +952,9 @@ choice that is selected here. config CPU_BIG_ENDIAN - bool "Build big-endian kernel" - help + bool "Build big-endian kernel" + depends on !LD_IS_LLD || LLD_VERSION >= 130000 + help Say Y if you plan on running a kernel with a big-endian userspace. config CPU_LITTLE_ENDIAN base-commit: 92bf22614b21a2706f4993b278017e437f7785b3 -- 2.30.1