From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A245C171B1 for ; Thu, 27 Jul 2023 13:10:25 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id D8EDAC433CD; Thu, 27 Jul 2023 13:10:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1690463425; bh=6XtOWBOqoXRqViOpbkT/L6kPfUHrdwju/8qldGnoyDg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nNXv11BxsjrMvsy0OEkh1MWpswr64xonr50/2PX69R2E14euI+UI3PbGhj06SB8Py LtB8AbThU8Gxtjl8PG/cY67xFhZunLjJ/Xd/a0hjTbjTdFwA5rsPzeo9AX36P4B4fK kxBbeb0kz8VuhMohWPZOSmc7xgUIKSD2IOlAk95h9NxZaNGX63kVvggldZ7aBe3uiP YTaec059Qral+eEZ/t6fx5JbwIaxvP5bNyNH4AoPRfCP69jg3YAhF0ltntNT0K+93M 6YMWaHQi1NamVamrfBBgiqbqhO8wuw23MA9kvZg4wgzvJV7kNmzmlCBwtEPcJxepIr USyEaLwhOnNDA== Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 6DAB240516; Thu, 27 Jul 2023 10:10:22 -0300 (-03) Date: Thu, 27 Jul 2023 10:10:22 -0300 From: Arnaldo Carvalho de Melo To: Masami Hiramatsu Cc: Alan Maguire , Jiri Olsa , Arnaldo Carvalho de Melo , Yonghong Song , dwarves@vger.kernel.org, bpf@vger.kernel.org, Steven Rostedt Subject: Re: [RESEND] BTF is not generated for gcc-built kernel with the latest pahole Message-ID: References: <20230726102534.9ebc4678ad2c9395cc9be196@kernel.org> <20230726200716.609d8433a7292eead95e7330@kernel.org> <6f0da094-5b49-954b-21e9-93f8c8cecc3f@oracle.com> <20230727093814.23681b2b0ac73aa89f368ae8@kernel.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230727093814.23681b2b0ac73aa89f368ae8@kernel.org> X-Url: http://acmel.wordpress.com Em Thu, Jul 27, 2023 at 09:38:14AM +0900, Masami Hiramatsu escreveu: > On Wed, 26 Jul 2023 15:46:03 +0100 > Alan Maguire wrote: > > > On 26/07/2023 12:07, Masami Hiramatsu (Google) wrote: > > > Hi Jiri, > > > > > > On Wed, 26 Jul 2023 12:04:08 +0200 > > > Jiri Olsa wrote: > > > > > >> On Wed, Jul 26, 2023 at 10:25:34AM +0900, Masami Hiramatsu wrote: > > >>> Hello, > > >>> (I resend this because kconfig was too big) > > >>> > > >>> I found that BTF is not generated for gcc-built kernel with that latest > > >>> pahole (v1.25). > > >> > > >> hi, > > >> I can't reproduce on my setup with your .config > > >> > > >> does 'bpftool btf dump file ./vmlinux' show any error? > > >> > > >> is there any error in the kernel build output? > > > > > > Yes, here it is. I saw these 2 lines. > > > > > > die__process: DW_TAG_compile_unit, DW_TAG_type_unit, DW_TAG_partial_unit or DW_TAG_skeleton_unit expected got INVALID (0x0)! > > > die__process: DW_TAG_compile_unit, DW_TAG_type_unit, DW_TAG_partial_unit or DW_TAG_skeleton_unit expected got INVALID (0x0)! > > > > This is strange, looks like some CUs were encoded incorrectly or we are > > parsing incorrectly. The error originates in die__process() and happens > > if the dwarf_tag() associated with the DIE isn't an expected unit; it's > > not even a valid tag value (0) it looks like. I've not built with gcc 13 > > yet so it's possible that's the reason you're seeing this, I'll try to > > reproduce it.. > > And this warning message is not good for debugging. It would better dump > the message with DIE index so that we can analyze the DWARF with other > tools. Good idea, I'll add that. - Arnaldo