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 CCB89C49EA2 for ; Mon, 21 Jun 2021 11:47:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B1A1F610C7 for ; Mon, 21 Jun 2021 11:47:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229918AbhFULuJ (ORCPT ); Mon, 21 Jun 2021 07:50:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49798 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229487AbhFULuI (ORCPT ); Mon, 21 Jun 2021 07:50:08 -0400 Received: from mail-oi1-x22d.google.com (mail-oi1-x22d.google.com [IPv6:2607:f8b0:4864:20::22d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C0A32C061574; Mon, 21 Jun 2021 04:47:54 -0700 (PDT) Received: by mail-oi1-x22d.google.com with SMTP id u11so19566038oiv.1; Mon, 21 Jun 2021 04:47:54 -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=sTLds6k8hTeNmy8LAUsRkWw0sTWUtxsqEbLIRxEoF04=; b=AVC5IPi5K8xUAsvToWKDgk11IDnAPVccYVBFUbMRed8RYy3zoMEMs26aiRw0EZlz94 dIsUm3YXjQkYa4D48HUyJlkinx4gToMjgp7BNT1miCCeaEZegkXrpyYFMMBmSI1uTQSr OFezb9397FptEX+3dDvnS2MDDkmG0wqNpUx9DkITTLxaWBYZztrwQ7fqg8UWo+0meNGo J7jjZiqzoIRiN4uDtcm4uwxGqWuR0HuRm/Q8wibZ2itqgTyk3WYt2jNzcR2ecNxqoip8 PFxDHIG9WApsNcjYXrXWrsSzoNCJyMi9flTHI9apMqph1uU4PjItgwPLZvqIhHpRc5N4 NgTw== 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=sTLds6k8hTeNmy8LAUsRkWw0sTWUtxsqEbLIRxEoF04=; b=pDrgdt3YJBumnbDZalJDghN333KZ3ugKdMJ+HC2BuLDNwwxiXp4bRwwCyrh20OxSa9 a83W9eHGMkZYVAZ8NQc//l7pVLRf9uBOm2emfzsYTCyxI20LazpgdxlRTdVvDPCptLI4 HRkg16RhtpXxorTWbaglND9cpHIyIMxmCHHZRdzZXnhQrLPi2JBGIWOfNWSiIsjligSD Xuf2ZixCg+H2dOnwNeHv1INYzFU9ZZ602/8WhQx3JUY5Was+ufKcOXRTwq/RsdC6xuXa CYxU7/7kcz/jntv7EebhN79tPuLwyK7JOvjwtj7rleEWoRzgEkrhtD2O6+uJ4PEByt1+ 4FRA== X-Gm-Message-State: AOAM533w7EdZ1XZvbj+aZ2bmPzLQ4p6C6uLZxpWKhBK3emOtg6WDElc7 Ze/CEHoMZocmRN5gLubiqDw= X-Google-Smtp-Source: ABdhPJymnCOHwsDHJB2uX5QOQRgQtnb2inCmaJ7ZxpaGL/krZBGf5/nMdqagr0un9AP49OgIkzzu5w== X-Received: by 2002:a05:6808:1415:: with SMTP id w21mr16583879oiv.150.1624276074194; Mon, 21 Jun 2021 04:47:54 -0700 (PDT) Received: from localhost ([2600:1700:e321:62f0:329c:23ff:fee3:9d7c]) by smtp.gmail.com with ESMTPSA id p17sm3903705otp.73.2021.06.21.04.47.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 21 Jun 2021 04:47:53 -0700 (PDT) Sender: Guenter Roeck Date: Mon, 21 Jun 2021 04:47:52 -0700 From: Guenter Roeck To: Arnd Bergmann Cc: Linux Kbuild mailing list , Masahiro Yamada , Michal Marek , David Brazdil , Marc Zyngier , Mikhail Petrov , Linux Kernel Mailing List , Marty Faltesek Subject: Re: [PATCH] kallsyms: fix nonconverging kallsyms table with lld Message-ID: <20210621114752.GA116119@roeck-us.net> References: <20210204152957.1288448-1-arnd@kernel.org> <20210609110531.GA1528247@roeck-us.net> <20210609151608.GA3389541@roeck-us.net> <20210609191553.GA2535199@roeck-us.net> <20210610120531.GA711216@roeck-us.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jun 10, 2021 at 02:26:50PM +0200, Arnd Bergmann wrote: > On Thu, Jun 10, 2021 at 2:05 PM Guenter Roeck wrote: > > On Wed, Jun 09, 2021 at 10:30:23PM +0200, Arnd Bergmann wrote: > > > > I thought I'd see the added symbols, but it looks like the only difference > > > > between the two files is the addresses. > > > > > > > > What am I missing ? > > > > > > I probably misremembered the part about 'objdump --syms' and there was > > > something more to it. > > > > > > Maybe this was the last version before converging? It looks like the '<' version > > > has one extra symbol ompared to the '>' version. The diff has no context, but I > > > > It is the difference between step 1 and 2. Why would diff on objdump not > > show the additional symbol ? Is it possible that the symbol is not added > > to the object file ? > > Note sure. The symbol must be in the object file, but perhaps the > 'objdump --syms' output skips a different set of symbols compared > to the list that is used as input for kallsyms, which comes from '${NM}'. > > Comparing the nm output might be another thing to try. > Just following up on this: As Murphy would have told us, the problem disappeared while trying to track it down. We'll add some instrumentation into the ChromeOS kernel build to get data once/if/when it shows up again. When that happens, we'll try to come up with a patch to show the symbol file differences in the kernel build and submit it upstream. Thanks, Guenter