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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 5D0F9C48BD1 for ; Wed, 9 Jun 2021 11:05:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 45DE9613BC for ; Wed, 9 Jun 2021 11:05:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238676AbhFILHc (ORCPT ); Wed, 9 Jun 2021 07:07:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49502 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238414AbhFILH3 (ORCPT ); Wed, 9 Jun 2021 07:07:29 -0400 Received: from mail-ot1-x336.google.com (mail-ot1-x336.google.com [IPv6:2607:f8b0:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 34465C061789; Wed, 9 Jun 2021 04:05:34 -0700 (PDT) Received: by mail-ot1-x336.google.com with SMTP id h24-20020a9d64180000b029036edcf8f9a6so23532443otl.3; Wed, 09 Jun 2021 04:05:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=36CQRkOY7QyghBxxf7GCQwquMv/Oiou6SopAZ61gqIk=; b=JOKKhNNrQp8FF3pWrjWT/rfnM1fUI/2DrXw/eHx8Wdydzv359k1GCQgMbKrFwGvzAG T8cEE0QnJr71W34jVwdTUjDduMxhS8NAbzrL6h9clHb+U2da3tHu9mULvpowpeCosJzn atq/nQQA/dEuvSn+sqVGXvPaA1W6P2C5u8q7LIzCqkdNME0/hdD/Yp47uznUapGpQWjx BX7PGlXNqxVklSFP11vAY/Uk0pHvRCwnJgCqILyLwJn8ktmDlgTGTDMEc6PEeb0ZQQrQ 9zpgti5F3vW7uZRPL6x9IOIP080S3v+MbA5FIRMzjeEYMsqUkK44NbgInmp9lGsfVgn/ Xl5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:from:to:cc:subject:message-id :references:mime-version:content-disposition:in-reply-to; bh=36CQRkOY7QyghBxxf7GCQwquMv/Oiou6SopAZ61gqIk=; b=GqRebFJK8y1FQXyIgcC1hwHgPbkhHK4gv4tk5yotpUq5ObOBrPn024DZuYtUoWkC0g OPUrn3g0P7I29/qHhPWMwWbA5DTtGxY14xH6wyYX7yAkYaVZjqMgGJvJn9tKf1ctOP7+ wP5itNur10GfEPWrzm/dRkXN8d6oPMkeGN6+XzLPG4XStvhrID8Eyc5pFu5PuXLNXrp6 pkFhERH1/4SFEWghz22ZFy0HtgGhdjIw4mUYHG9n7ryUhWuVeGFG5E85AvPA78hRt5NQ vsLm7Zg3T7HgfkmGdsNFUEGAxe03DQe8uzHK5hfb0sg9SHAaShGwPv+96gS9z0AGsloP hqXA== X-Gm-Message-State: AOAM530wdH0aXC8yJgdpXJr3QQwmjvJdAnrAHiDp4QZKjjPjrBgAuTml GdrL+bMEJVG7BGnaIlVOGmOpqgIszs0= X-Google-Smtp-Source: ABdhPJyKi5DmKghplNOitTDkrAZM+inOHwPYnbD2iakRM8Q9AIcesbNAOe7mZcuQInvcEw7wYXZcAw== X-Received: by 2002:a9d:6f93:: with SMTP id h19mr11715637otq.100.1623236733441; Wed, 09 Jun 2021 04:05:33 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id z22sm1282396ooj.6.2021.06.09.04.05.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Jun 2021 04:05:32 -0700 (PDT) Sender: Guenter Roeck Date: Wed, 9 Jun 2021 04:05:31 -0700 From: Guenter Roeck To: Arnd Bergmann Cc: linux-kbuild@vger.kernel.org, Masahiro Yamada , Michal Marek , Arnd Bergmann , David Brazdil , Marc Zyngier , Mikhail Petrov , linux-kernel@vger.kernel.org, mfaltesek@google.com Subject: Re: [PATCH] kallsyms: fix nonconverging kallsyms table with lld Message-ID: <20210609110531.GA1528247@roeck-us.net> References: <20210204152957.1288448-1-arnd@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210204152957.1288448-1-arnd@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Arnd, On Thu, Feb 04, 2021 at 04:29:47PM +0100, Arnd Bergmann wrote: > From: Arnd Bergmann > > ARM randconfig builds with lld sometimes show a build failure > from kallsyms: > > Inconsistent kallsyms data > Try make KALLSYMS_EXTRA_PASS=1 as a workaround > > The problem is the veneers/thunks getting added by the linker extend > the symbol table, which in turn leads to more veneers being needed, > so it may take a few extra iterations to converge. > > This bug has been fixed multiple times before, but comes back every time > a new symbol name is used. lld uses a different set of idenitifiers from > ld.bfd, so the additional ones need to be added as well. > > I looked through the sources and found that arm64 and mips define similar > prefixes, so I'm adding those as well, aside from the ones I observed. I'm > not sure about powerpc64, which seems to already be handled through a > section match, but if it comes back, the "__long_branch_" and "__plt_" > prefixes would have to get added as well. > This is such a whack-a-mole. The problem is hitting us yet again. I suspect it may be due to a new version of lld using new symbols, but I didn't really try to track it down. Is there an easy way to search for missed symbols ? In this context .. is there a chance to apply [1] after all ? This is getting really time consuming and annoying, and I really dislike having to fix the same problem over and over again. Thanks, Guenter --- [1] https://patchwork.kernel.org/project/linux-kbuild/patch/20200910153204.156871-1-linux@roeck-us.net/