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=-5.5 required=3.0 tests=BAYES_00,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 4A918C433FE for ; Wed, 9 Dec 2020 07:22:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 095B123B84 for ; Wed, 9 Dec 2020 07:22:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726580AbgLIHW0 (ORCPT ); Wed, 9 Dec 2020 02:22:26 -0500 Received: from mail-ej1-f47.google.com ([209.85.218.47]:37907 "EHLO mail-ej1-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725829AbgLIHW0 (ORCPT ); Wed, 9 Dec 2020 02:22:26 -0500 Received: by mail-ej1-f47.google.com with SMTP id a16so625847ejj.5 for ; Tue, 08 Dec 2020 23:22:10 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:from:to:cc:references:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=zKreOXQg8Zew2FOkd7kR5R18DPUcCLB8b6VPYDaoryU=; b=IDGPuMwnD01rbkRJBU3naebqldfaNIm1mwHOxjiHINXFCW5ZfFildbM9+9+GUahhZJ JfQZT4XTUBTtnDMIZl4CahQnTiPnSc8pO6ZVkniQtVwOQeVEU49oL/8O2lYkMQLnSffQ mjp3hYMzRzpHZLdcVCm6Snpf+S1hjJbtiVEAYyrtawRxrahMPtvWVs98Xbl4cgKstHQZ 7G09xKmK/L0mZyLOMAU43LnOxUvzyKC6iR0jOk0BlhkKpJwX+coJFkrUsKwtUnkshTRR +VPxw0GNwU6tCPvjDoBFsubecBUWl6hnVa0iowy6xleN+dkMnXnOCyN/sjqigiVd6jLN 1LpA== X-Gm-Message-State: AOAM531ttOOB8JAdFYJ1PbGf19XNfI9jn1EOfD/wpW+DR6u4DZjTpTv1 OwOhkAdDnCU92Lakredi8rI= X-Google-Smtp-Source: ABdhPJxIgm0Dp8dwPVybk5Qs+kL7S9DlS9s7hm3yDKsgMo33AJ7bJmP4sxuCToLpd5nkmH6DhQRdDg== X-Received: by 2002:a17:906:1c8e:: with SMTP id g14mr941266ejh.5.1607498504678; Tue, 08 Dec 2020 23:21:44 -0800 (PST) Received: from ?IPv6:2a0b:e7c0:0:107::49? ([2a0b:e7c0:0:107::49]) by smtp.gmail.com with ESMTPSA id be6sm675122edb.29.2020.12.08.23.21.43 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 08 Dec 2020 23:21:44 -0800 (PST) Subject: Re: 5.4 and 4.19 fix for LLVM_IAS/clang-12 From: Jiri Slaby To: Nick Desaulniers , Greg KH , Sasha Levin Cc: stable , Jian Cai , Fangrui Song , Sami Tolvanen , Borislav Petkov , Nathan Chancellor , clang-built-linux References: Message-ID: Date: Wed, 9 Dec 2020 08:21:43 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.5.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 09. 12. 20, 8:20, Jiri Slaby wrote: > On 09. 12. 20, 1:12, Nick Desaulniers wrote: >> Dear stable kernel maintainers, >> Please consider accepting the following backport to 5.4 and 4.19 of >> commit 4d6ffa27b8e5 ("x86/lib: Change .weak to SYM_FUNC_START_WEAK for >> arch/x86/lib/mem*_64.S"), attached. >> >> The patch to 5.4 had a conflict due to 5.4 missing upstream commit >> e9b9d020c487 ("x86/asm: Annotate aliases") which first landed in >> v5.5-rc1. >> >> The patch to 4.19 had a conflict due to 4.19 missing the above commit >> and ffedeeb780dc ("linkage: Introduce new macros for assembler >> symbols") which also first landed in v5.5-rc1 but was backported to >> linux-5.4.y as commit 840d8c9b3e5f ("linkage: Introduce new macros for >> assembler symbols") which shipped in v5.4.76. >> >> This patch fixes a build error from clang's assembler when building >> with Clang-12, which now errors when symbols are redeclared with >> different bindings.  We're using clang's assembler in Android and >> ChromeOS for 4.19+. >> >> Jiri, would you mind reviewing the 4.19 patch (or both)?  It simply >> open codes what the upstream macros would expand to; this can be and >> was observed from running: > > You don't have to touch (expand) __memcpy, __memmove, and __memset, right? Also, no need for doubled p2align. > thanks, -- js