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=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 82E0AC433E0 for ; Thu, 14 Jan 2021 21:53:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 504E123AA7 for ; Thu, 14 Jan 2021 21:53:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727196AbhANVxh (ORCPT ); Thu, 14 Jan 2021 16:53:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48016 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726977AbhANVxf (ORCPT ); Thu, 14 Jan 2021 16:53:35 -0500 Received: from mail-io1-xd2d.google.com (mail-io1-xd2d.google.com [IPv6:2607:f8b0:4864:20::d2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B1599C061575 for ; Thu, 14 Jan 2021 13:52:54 -0800 (PST) Received: by mail-io1-xd2d.google.com with SMTP id q1so14275223ion.8 for ; Thu, 14 Jan 2021 13:52:54 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:reply-to:from:date:message-id :subject:to:cc; bh=25UGyailuGkSlV0rEAoFPYluemtWcBTnklauhq8H0ck=; b=N1graEbZFfiWEd2Yl780jQH/sTD70P8lgY8ZwyRUE7r/dEpF3EOp0SmgelThj0Qe76 EIhGa1MBqaTYBUMDx34ODBuiGOqkXvp/jUxX6Lh6mDvUDTczocbFrrBzMCg6NstCnKmT ps3AxZB0wIAA3dm3ZPWna7VJNl7urvLGZ0xNY3HXFt6pPlD+6mz2qPiopThTQFIqZDGr /pXHTx0FPj1KUfXrRLfQt4WS+GeGkQvwhza5qizKLZDj9Fsl714DmtfnY4O/pvKROrPV GtUmCR9lYZN9yX9l855A3UK478UwlkZVKJmXBGx5TEoQhpbQBXEquIuNSyHb5BW2iVAp yWKA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:reply-to :from:date:message-id:subject:to:cc; bh=25UGyailuGkSlV0rEAoFPYluemtWcBTnklauhq8H0ck=; b=SY6rL0J2TOevhNklKfAEPCZwixr5ONBEr3yG0lkgR3pd6yzt/niGTeF1wfuy0kzN4p OklopIU4EmUTHAskp5PP2twqlObiVDRyqDb/2awvf15rtwf7zD0zZJ6EthCvFneJUmPI A2iLBhsepsyDsfGnPLcgf0+RZQYaijbKGigR1fHeRtXe+yC7k+QtuDf+bL6CHXktuc+n 3lgp35cz1POd6rkkR+3Mma1UqN5oAZPOtsuWCcBIhL2zJjhd6HKHkvUSxMv+juAE44jc 1AQLuxTIyntELR6ABqSV+0t/+w96ABQahdGLjsAKTG0yyU1f2QIcq3cY8avwe1nrrTls oYsw== X-Gm-Message-State: AOAM531ReXdyq2b6K2JiyYhevGFHiq9SdFlcvOdEzweYRNNcGwJ8sZKL Km551CHRRjaO1piC8/vVfU+HprKlvYZUmvUWEPc= X-Google-Smtp-Source: ABdhPJyAT2jWT+u7Yqqd//3BLiGQiACkWSaJUa7ivIwhLe+anx/kPh10FBNju+yc5+LJ8nfj79c9wPgDQHgHtNZB6mg= X-Received: by 2002:a92:d990:: with SMTP id r16mr8530650iln.10.1610661173930; Thu, 14 Jan 2021 13:52:53 -0800 (PST) MIME-Version: 1.0 References: <20201204011129.2493105-1-ndesaulniers@google.com> <20201204011129.2493105-3-ndesaulniers@google.com> <5707cd3c-03f2-a806-c087-075d4f207bee@fb.com> In-Reply-To: Reply-To: sedat.dilek@gmail.com From: Sedat Dilek Date: Thu, 14 Jan 2021 22:52:41 +0100 Message-ID: Subject: Re: [PATCH v3 0/2] Kbuild: DWARF v5 support To: Yonghong Song Cc: Nick Desaulniers , Jiri Olsa , Andrii Nakryiko , Arnaldo Carvalho de Melo , Caroline Tice , Arvind Sankar , Jakub Jelinek , Fangrui Song , Clang-Built-Linux ML , Nick Clifton , bpf , Masahiro Yamada Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Thu, Jan 14, 2021 at 9:11 PM Sedat Dilek wrote: > > On Thu, Jan 14, 2021 at 8:13 PM Yonghong Song wrote: > > > > > > > > On 1/14/21 11:01 AM, Nick Desaulniers wrote: > > > On Thu, Jan 14, 2021 at 10:53 AM Nick Desaulniers > > > wrote: > > >> > > >> On Wed, Jan 13, 2021 at 10:18 PM Sedat Dilek wrote: > > >>> > > >>> On Wed, Jan 13, 2021 at 11:25 PM Caroline Tice wrote: > > >>>> > > >>>> On Tue, Jan 12, 2021 at 3:17 PM Sedat Dilek wrote: > > >>>>> > > >>>>> Unfortunately, I see with CONFIG_DEBUG_INFO_DWARF5=y and > > >>>>> CONFIG_DEBUG_INFO_BTF=y: > > >>>>> > > >>>>> die__process_inline_expansion: DW_TAG_INVALID (0x48) @ <0x3f0dd5a> not handled! > > >>>>> die__process_function: DW_TAG_INVALID (0x48) @ <0x3f0dd69> not handled! > > >> > > >> I can confirm that I see a stream of these warnings when building with > > >> this patch series applied, and those two configs enabled. > > >> > > >> rebuilding with `make ... V=1`, it looks like the call to: > > >> > > >> + pahole -J .tmp_vmlinux.btf > > >> > > >> is triggering these. > > >> > > >> Shall I send a v4 that adds a Kconfig dependency on !DEBUG_INFO_BTF? > > >> Does pahole have a bug tracker? > > > > pahole could have issues for dwarf5 since as far as I know, people just > > use dwarf2/dwarf4 with config functions in the kernel. > > > > Where is the link of the patch to add CONFIG_DEBUG_INFO_DWARF5 to linux? > > I think you can add CONFIG_DEBUG_INFO_DWARF5 to kernel with dependency > > of !CONFIG_DEBUG_INFO_BTF. At the same time, people can debug pahole > > issues. Once it is resolved, !CONFIG_DEBUG_INFO_BTF dependency can be > > removed with proper pahole version change in kernel. > > > > Yeah, sounds like a good idea. > Today, I have observed and reported (see [1]) bpf/btf/pahole issues with Clang v12 (from apt.llvm.org) and DWARF-4 ("four"). Cannot speak for other compilers and its version. - Sedat - [1] https://lore.kernel.org/bpf/CA+icZUWb3OyaSQAso8LhsRifZnpxAfDtuRwgB786qEJ3GQ+kRw@mail.gmail.com/T/#m6d05cc6c634e9cee89060b2522abc78c3705ea4c > > > > > > > FWIW, my distro packages pahole v1.17; rebuilt with ToT v1.19 from > > > source and also observe the issue. > > >