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=-21.4 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 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 4995AC433DB for ; Sun, 7 Feb 2021 02:31:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 22B4764D9D for ; Sun, 7 Feb 2021 02:31:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229609AbhBGCb0 (ORCPT ); Sat, 6 Feb 2021 21:31:26 -0500 Received: from mail.kernel.org ([198.145.29.99]:37248 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229506AbhBGCbY (ORCPT ); Sat, 6 Feb 2021 21:31:24 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6CF4264E8C; Sun, 7 Feb 2021 02:30:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612665043; bh=IzYeZSry0qXTzjT2UN+6iWEQJbFKYdFQv0CID8sfJP8=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KTo8rm0rUEs4PkiNtiEDrp7e46mzt4rKMvVYBTMAfI+KHFCpg90Fj/RQrVNKtj743 TCUcYOr8yRlgrNKohl7iqcYa+DiY1gXJMPouSJIOJdIUEyo32AFwr+LOYoDInP1FM+ 99EJ6C3uSvKFUBVqhZZbL3pWEAHoXhoR8PDlDU3aFwBJxcV2nNCxviifi3Y807KzVy O0BwonNqz1YptUN5zsS33kKY842JsIoU/UTcGtNEOet/crs27jBowMoHdI9WduGmEu 9eGi763RN0w/2LUoNqCg9BUQ852ba66E/uNotTKAKUHk/JXIEmZSUDNotYZGQ5O3OX tWLCFCL9MNMCw== Date: Sat, 6 Feb 2021 19:30:41 -0700 From: Nathan Chancellor To: Catalin Marinas , Will Deacon Cc: Arnd Bergmann , Nick Desaulniers , linux-kernel@vger.kernel.org, clang-built-linux@googlegroups.com, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCH] arm64: Make CPU_BIG_ENDIAN depend on !LD_IS_LLD Message-ID: <20210207023041.GA655027@ubuntu-m3-large-x86> References: <20210202022441.1451389-1-nathan@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210202022441.1451389-1-nathan@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Feb 01, 2021 at 07:24:42PM -0700, Nathan Chancellor wrote: > Similar to commit 28187dc8ebd9 ("ARM: 9025/1: Kconfig: CPU_BIG_ENDIAN > depends on !LD_IS_LLD"), ld.lld does not support aarch64 big endian, > leading to the following build error when CONFIG_CPU_BIG_ENDIAN is > selected: > > ld.lld: error: unknown emulation: aarch64linuxb > > There are not currently plans to implement big endian support for > aarch64 in ld.lld but if it should be supported in the future, this > symbol can depend on the version that first supports it. In the > meantime, prevent this symbol from being selected to avoid these type > of build errors. > > 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 > Reported-by: Arnd Bergmann > Signed-off-by: Nathan Chancellor Fangrui has pushed proper aarch64linuxb and elf64-bigaarch64 for ld.lld: https://reviews.llvm.org/D96211 https://reviews.llvm.org/D96188 This patch is needed for OUTPUT_FORMAT in the vDSO to work properly: https://reviews.llvm.org/D96214 Once these are all merged into LLVM 13, I will update this to be: depends on !LD_IS_LLD || LLD_VERSION >= 130000 Cheers, Nathan > --- > arch/arm64/Kconfig | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index f39568b28ec1..5ddf9fe7b4ee 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 > + help > Say Y if you plan on running a kernel with a big-endian userspace. > > config CPU_LITTLE_ENDIAN > > base-commit: 88bb507a74ea7d75fa49edd421eaa710a7d80598 > -- > 2.30.0 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel