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 40DA4247291; Mon, 19 Jan 2026 10:00:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768816840; cv=none; b=CRFEjZPIN7aKN/dVzq8Z0rEZjTmv55h4ypIWCJOUU7oNLnD/HZpwtImCRQNo0jvhLuWzk412ieWVeE5HVXg9ZJZRMkU3HLMHo1BS4ooVUd9p0//4b0iUpHGyk3QXvg02wORGvRP2TPEXfunuCj+yfHqZsS6jenVPj8oExKM8+/U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768816840; c=relaxed/simple; bh=zBU8QQHYrFrsHNhOOFAEymGNK0zcmy/ffgxlqEoVK/g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=nyY4x5W3AEMLRbE6oVSWLsO9NO6rLP7fCo6VKuF1vTlM0ypj9aSuw8It/fKiqmOh/ssQWWETL6ey6j+X1znhLw/nqGat1ZRWYh/nF+Z9x3wMlsbXBdP1gTeFDm5XzTOXJM5FZJEeiAqMCAnOMS0u+pmDqKzFHf1rtQ6wP/12oQU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tpxOnLrg; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="tpxOnLrg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D81BC116C6; Mon, 19 Jan 2026 10:00:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1768816840; bh=zBU8QQHYrFrsHNhOOFAEymGNK0zcmy/ffgxlqEoVK/g=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=tpxOnLrgpH84sLM7Z7/oZVp9q812KHBBZHcpxhJtH33vHqi6KeAcRDLNB+0JL/gbF zYlHctIs4hSR1rtzHGJeuTAs2XkHkAH3RKAOZkww6Er1Ppxc9KPZsEzS+fUVcrk5jO a87/egxPsHbzCIl64YDDP2Vh5S90StVdwwY7d/jU= Date: Mon, 19 Jan 2026 11:00:37 +0100 From: Greg KH To: Luis Augenstein Cc: nathan@kernel.org, nsc@kernel.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, maximilian.huber@tngtech.com Subject: Re: [PATCH 00/14] Add SPDX SBOM generation tool Message-ID: <2026011938-varying-rinsing-63c6@gregkh> References: <20260119064731.23879-1-luis.augenstein@tngtech.com> <2026011916-idealism-paternal-cfd5@gregkh> Precedence: bulk X-Mailing-List: linux-kbuild@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: <2026011916-idealism-paternal-cfd5@gregkh> On Mon, Jan 19, 2026 at 10:51:29AM +0100, Greg KH wrote: > On Mon, Jan 19, 2026 at 07:47:17AM +0100, Luis Augenstein wrote: > > This patch series introduces a Python-based tool for generating SBOM > > documents in the SPDX 3.0.1 format for kernel builds. > > > > A Software Bill of Materials (SBOM) describes the individual components > > of a software product. For the kernel, the goal is to describe the > > distributable build outputs (typically the kernel image and modules), > > the source files involved in producing these outputs, and the build > > process that connects the source and output files. > > > > To achieve this, the SBOM tool generates three SPDX documents: > > > > - sbom-output.spdx.json > > Describes the final build outputs together with high-level > > build metadata. > > > > - sbom-source.spdx.json > > Describes all source files involved in the build, including > > licensing information and additional file metadata. > > > > - sbom-build.spdx.json > > Describes the entire build process, linking source files > > from the source SBOM to output files in the output SBOM. > > > > The sbom tool is optional and runs only when CONFIG_SBOM is enabled. It > > is invoked after the build, once all output artifacts have been > > generated. Starting from the kernel image and modules as root nodes, > > the tool reconstructs the dependency graph up to the original source > > files. Build dependencies are primarily derived from the .cmd files > > generated by Kbuild, which record the full command used to build > > each output file. > > > > Currently, the tool only supports x86 and arm64 architectures. > > > > Co-developed-by: Maximilian Huber > > Signed-off-by: Maximilian Huber > > Signed-off-by: Luis Augenstein > > This is great work, thank you so much for doing this! > > Note, I just tested the series, on 6.19-rc6, and with CONFIG_SBOM > enabled, I get this following "message" at the end of the build when it > generates the sbom: > > make[3]: Nothing to be done for 'sbom'. > > Is that intentional? Ah, it's on the second run that I see this: End of the first run that builds the sbom files: ... OBJCOPY arch/x86/boot/vmlinux.bin AS arch/x86/boot/header.o LD arch/x86/boot/setup.elf OBJCOPY arch/x86/boot/setup.bin BUILD arch/x86/boot/bzImage Kernel: arch/x86/boot/bzImage is ready (#526) DESCEND sbom GEN sbom-build.spdx.json sbom-output.spdx.json [INFO] Skipped creating a dedicated source SBOM because source files cannot be reliably classified when the source and object trees are identical. Added source files to the build SBOM instead. Then I build again and get the following: DESCEND objtool CALL scripts/checksyscalls.sh INSTALL libsubcmd_headers Kernel: arch/x86/boot/bzImage is ready (#526) DESCEND sbom make[3]: Nothing to be done for 'sbom'. That make message shouldn't probably show up, right? Also, I don't know if this is even possible, or you care about it, but if you have ANY sbom file present, it is not regenerated: $ rm sbom-build.spdx.json sbom-output.spdx.json $ touch sbom-build.spdx.json sbom-output.spdx.json $ make DESCEND objtool CALL scripts/checksyscalls.sh INSTALL libsubcmd_headers Kernel: arch/x86/boot/bzImage is ready (#526) DESCEND sbom make[3]: Nothing to be done for 'sbom'. So, if I change the build config, which will change the sbom output, will the sbom be regenerated? Should it depend on the config .h files to know this? thanks, greg k-h