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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B489FC00528 for ; Thu, 27 Jul 2023 21:36:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232085AbjG0Vg5 (ORCPT ); Thu, 27 Jul 2023 17:36:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56508 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229931AbjG0Vg4 (ORCPT ); Thu, 27 Jul 2023 17:36:56 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4C3F1C3; Thu, 27 Jul 2023 14:36:52 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id D984A61EB8; Thu, 27 Jul 2023 21:36:51 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8D72AC433C8; Thu, 27 Jul 2023 21:36:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690493811; bh=duAwVmFYmsUINs8hFVbW/zohvuZX6TUh3Gnxn1i9JaI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=VnkrMICyDKHI52bpNsVeWb1AIXCLlOc90Zm+WJzG7JhU/D/eh32guTyhJs9VbOXeY VLunSyQzAZmzTpbjTD0/0bwVy6AP11F0L45gerinT+7xNzw+bUWgc1NJDEOd0uEw7k 0oizeR8ID0C2ayjOTINy9zIDUAhG5c3tNnJg2rSvPeFBObmg5Lisx+nvXBwG4+Xl67 qM9qBKsNHyW1L5vzqBQ1hNJg2A3IUp0YOwTv0VvVK+IsuC1joDQwV/a5XSzbXqGwPQ WEEaOEhQLooEPvMJ6QS2mIGeMoxc3tmMofUdWTZQq7jpKKXznadVu7vzJ5i57P+phO A0wy5jcHn6vKQ== Date: Thu, 27 Jul 2023 14:36:48 -0700 From: Nathan Chancellor To: Tiezhu Yang Cc: Arnd Bergmann , linux-arm-kernel@lists.infradead.org, linux-riscv@lists.infradead.org, loongarch@lists.linux.dev, linux-arch@vger.kernel.org, bpf@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, loongson-kernel@lists.loongnix.cn Subject: Re: [PATCH v3 1/2] asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch Message-ID: <20230727213648.GA354736@dev-arch.thelio-3990X> References: <1687443219-11946-1-git-send-email-yangtiezhu@loongson.cn> <1687443219-11946-2-git-send-email-yangtiezhu@loongson.cn> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1687443219-11946-2-git-send-email-yangtiezhu@loongson.cn> Precedence: bulk List-ID: X-Mailing-List: linux-perf-users@vger.kernel.org Hi Tiezhu and Arnd, On Thu, Jun 22, 2023 at 10:13:38PM +0800, Tiezhu Yang wrote: > Now we specify the minimal version of GCC as 5.1 and Clang/LLVM as 11.0.0 > in Documentation/process/changes.rst, __CHAR_BIT__ and __SIZEOF_LONG__ are > usable, it is probably fine to unify the definition of __BITS_PER_LONG as > (__CHAR_BIT__ * __SIZEOF_LONG__) in asm-generic uapi bitsperlong.h. > > In order to keep safe and avoid regression, only unify uapi bitsperlong.h > for some archs such as arm64, riscv and loongarch which are using newer > toolchains that have the definitions of __CHAR_BIT__ and __SIZEOF_LONG__. > > Suggested-by: Xi Ruoyao > Link: https://lore.kernel.org/all/d3e255e4746de44c9903c4433616d44ffcf18d1b.camel@xry111.site/ > Suggested-by: Arnd Bergmann > Link: https://lore.kernel.org/linux-arch/a3a4f48a-07d4-4ed9-bc53-5d383428bdd2@app.fastmail.com/ > Signed-off-by: Tiezhu Yang > --- > arch/arm64/include/uapi/asm/bitsperlong.h | 24 ---------------------- > arch/loongarch/include/uapi/asm/bitsperlong.h | 9 -------- > arch/riscv/include/uapi/asm/bitsperlong.h | 14 ------------- > include/uapi/asm-generic/bitsperlong.h | 13 +++++++++++- > tools/arch/arm64/include/uapi/asm/bitsperlong.h | 24 ---------------------- > .../arch/loongarch/include/uapi/asm/bitsperlong.h | 9 -------- > tools/arch/riscv/include/uapi/asm/bitsperlong.h | 14 ------------- > tools/include/uapi/asm-generic/bitsperlong.h | 14 ++++++++++++- > tools/include/uapi/asm/bitsperlong.h | 6 ------ > 9 files changed, 25 insertions(+), 102 deletions(-) > delete mode 100644 arch/arm64/include/uapi/asm/bitsperlong.h > delete mode 100644 arch/loongarch/include/uapi/asm/bitsperlong.h > delete mode 100644 arch/riscv/include/uapi/asm/bitsperlong.h > delete mode 100644 tools/arch/arm64/include/uapi/asm/bitsperlong.h > delete mode 100644 tools/arch/loongarch/include/uapi/asm/bitsperlong.h > delete mode 100644 tools/arch/riscv/include/uapi/asm/bitsperlong.h I think this change has backwards compatibility concerns, as it breaks building certain host tools on the stable releases (at least 6.4 and 6.1, as that is where I noticed this). I see the following error on my aarch64 system: $ make -skj"$(nproc)" ARCH=x86_64 CROSS_COMPILE=x86_64-linux- mrproper defconfig prepare In file included from /usr/include/asm/bitsperlong.h:1, from /usr/include/asm-generic/int-ll64.h:12, from /usr/include/asm-generic/types.h:7, from /usr/include/asm/types.h:1, from tools/include/linux/types.h:13, from tools/arch/x86/include/asm/orc_types.h:9, from scripts/sorttable.h:96, from scripts/sorttable.c:201: tools/include/asm-generic/bitsperlong.h:14:2: error: #error Inconsistent word size. Check asm/bitsperlong.h 14 | #error Inconsistent word size. Check asm/bitsperlong.h | ^~~~~ A reverse bisect of 6.4 to 6.5-rc1 points to this patch. This Fedora rawhide container has kernel-headers 6.5.0-0.rc2.git0.1.fc39 and the error disappears when I downgrade to 6.4.0-0.rc7.git0.1.fc39. I have not done a ton of triage/debugging so far, as I am currently hunting down other regressions, but I figured I would get an initial report out, since I noticed it when validating LLVM from the new release/17.x branch. If there is any additional information I can provide or patches I can test, I am more than happy to do so. Cheers, Nathan