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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 66E2CE7FDF3 for ; Mon, 2 Feb 2026 23:15:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To: Content-Transfer-Encoding:Content-Type:MIME-Version:References:Message-ID: Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=ddf2ioH2Ktuyztsu5afd6+uqRjbgML42099HAKIrcNg=; b=WD5K8gXrhV4wllq9Scf6u8bIo6 VYi8y4F6+AUv9g3CB21W8gTwpur4hOsfjTVoYH0tU/nfnsZX42BmYdQTYOg7uq9lLjSwm8WElEhzy DUo6RRqQGMguLTtO5fgSXJpboSf9yVwkRxGQpv5m4mepJXzhKlSmhrjZI/iCkPfTqqe9tnQGj9Edw b3u3WH+urnqm/ei31gUaEa+YEQJD4lnvfsTDgwhiNbKpaBnbNymhzSgOlLLMDezMZtkXjq8QOh9YJ Mzv2b1u1qPvwBs/stNBTPGeWD7We81WfQ3l6QvIuzkE3z/TNKuzvoxjE8PMfN6Q4H6FtpKSVo6VOV S5GNUs7w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1vn38Y-00000005kRI-00vR; Mon, 02 Feb 2026 23:15:18 +0000 Received: from tor.source.kernel.org ([2600:3c04:e001:324:0:1991:8:25]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1vn38W-00000005kRC-43AQ for linux-arm-kernel@lists.infradead.org; Mon, 02 Feb 2026 23:15:17 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by tor.source.kernel.org (Postfix) with ESMTP id E8281600AA; Mon, 2 Feb 2026 23:15:15 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9FA2DC116C6; Mon, 2 Feb 2026 23:15:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1770074115; bh=1XwHPN4AupLXvP+bN6kH/Ou8DAfIc/Ke4SzidTUEdR4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=acfQ42a8kNzQpUvKE3nNJtuaqyG9amvuJG30UTwrzTlbtNbQEGu43n7K4ukBgExnR fJEVD2y9wCADtuQYLA0md/3egtYljsk83cj+VnaEjhcPrNfXypxALKrWQ1g+Pcltuj U5AGuhaw7lLkR6wmXrZqn+C/Io5/B4jjnZh9K9ge8bSew/OweBx5TR6NlEW1SiXy+b TottQoB9xPLK5jvysSnZ/js5cXxQU8u8jsULAsFeiJFzfceV1YFhxS4m5kAwxOspny 1Be+K49shZdkgkHFKasAAD4qeW5YJo8ucGy9+MLpMpEHgKImdd98b6Zwe2F0QGDeHP QIembv1zbS5Tg== Date: Mon, 2 Feb 2026 16:15:08 -0700 From: Nathan Chancellor To: Thomas =?iso-8859-1?Q?Wei=DFschuh?= Cc: Naman Jain , Nicolas Schier , Catalin Marinas , Will Deacon , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H . Peter Anvin" , Masahiro Yamada , Miguel Ojeda , Tamir Duberstein , Steven Rostedt , Kees Cook , Ard Biesheuvel , linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Saurabh Singh Sengar Subject: Re: [RFC PATCH] kbuild: Make --build-id linker flag configurable Message-ID: <20260202231508.GB2319189@ax162> References: <20260202110631.978412-1-namjain@linux.microsoft.com> <20260202151101-d5558a6f-88d0-41dd-8816-18957a029ce8@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260202151101-d5558a6f-88d0-41dd-8816-18957a029ce8@linutronix.de> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Mon, Feb 02, 2026 at 03:15:30PM +0100, Thomas Weißschuh wrote: > On Mon, Feb 02, 2026 at 11:06:31AM +0000, Naman Jain wrote: > > I am trying to implement reproducible builds for one of my product > > kernel. I referred https://reproducible-builds.org/docs/build-path/ > > and tried to use both -fdebug-prefix-map=OLD=NEW and > > -fmacro-prefix-map=OLD=NEW, but still could not achieve bit by bit > > binary reproducibility without overwriting build-id to none. > > If I move the kernel to same path in other setup, I was able to create > > same binary hash, however, without it, there is some difference in > > build-id hash values. > > Can you force the same build path during package building? > That should avoid this issue. Yeah, I think that it would be better to document this in Documentation/kbuild/reproducible-builds.rst, as opposed to adding a hack to disable the build ID altogether. It seems easy enough to make the paths consistent between machines and environments by using a container or such. The new scripts/container in -next could help there. Cheers, Nathan