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 40BAD361DCA; Thu, 4 Dec 2025 17:50:01 +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=1764870601; cv=none; b=I+Knz8eFvFNvUmFrTQsjafvmDJSi4rFqeJAXKA0blrWdBl8TEK9CPbWeT3FQvmEgFbSoOlm27MHkIIwGsvDxjY8RYJgyD2i28NMR8lcKGuKb/HLzAf4I9p7esG2wArYWWXjLastqFEWilDbTOn8JqbSSBnklFJQXqiuIBV1CjTs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764870601; c=relaxed/simple; bh=awRZnETkvcO/0zESeHrh1CN+vKjRx9N4IAlDBab0RYw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=R3lh/Hh+aKAKaIwUVC5+A4YP726utQWsi1chyvtDtPJw7FteOEyW8qQ84DVvRuFPh70CNTeMGFw8WJ11G3ICkIwm9mXZZCEc+Cx+rTiDvYxXtaTJTfeYP3UBUdQ3MOsky+brZdmixiZukv3JUKIZbRUjZGZfR9yWcN44TjxCbes= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=LEjMGZgP; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="LEjMGZgP" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1AC28C116C6; Thu, 4 Dec 2025 17:49:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764870601; bh=awRZnETkvcO/0zESeHrh1CN+vKjRx9N4IAlDBab0RYw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=LEjMGZgP4IE+zMhT6di3NRw6AEvegViG4+PyBP8195dyhapsi0ZgVIXAmaLytgyNG m00o9mXM1Eivr365qBNN1QZ1E6v3Ldx2SSOY4+rrxAJlCMHLPgMYuYcM7bS70ca6h5 MoLt3EFFjT7/N8NRqdBnyFmB5cZjyPe1s4L8r9CdnllK/7BV9ez8e28l7L/C44V+7T rT8F8ydd+alieiYIuVBUhmfJdr2FMYe176/lIFQd5rNRkoWX29Sdvb8UZucq6trcDD 9IgNnluyDnnMcid1Pcjgus8ZXVfluWYAFQ1eo8bs0/p3Avt+3hdHSQbRNTvtHDLylK FqRQL5j9pAryw== Date: Thu, 4 Dec 2025 10:49:54 -0700 From: Nathan Chancellor To: xur@google.com Cc: Masahiro Yamada , Nicolas Schier , Nick Desaulniers , Bill Wendling , Justin Stitt , Miguel Ojeda , Thomas Gleixner , Alice Ryhl , Sami Tolvanen , "Mike Rapoport (Microsoft)" , Rafael Aquini , Michael Ellerman , Stafford Horne , Christophe Leroy , Piotr Gorski , Teresa Johnson , linux-kernel@vger.kernel.org, linux-kbuild@vger.kernel.org, llvm@lists.linux.dev Subject: Re: [PATCH v5 0/2] kbuild: distributed build support for Clang ThinLTO Message-ID: <20251204174954.GA1177092@ax162> References: <20251028182822.3210436-1-xur@google.com> Precedence: bulk X-Mailing-List: llvm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251028182822.3210436-1-xur@google.com> Hi Rong, On Tue, Oct 28, 2025 at 06:28:20PM +0000, xur@google.com wrote: First of all, my apologies for taking so long to get to testing and reviewing this patchset. > Rong Xu (2): > kbuild: move vmlinux.a build rule to scripts/Makefile.vmlinux_a > kbuild: distributed build support for Clang ThinLTO > > .gitignore | 2 + > Makefile | 25 +++++------- > arch/Kconfig | 19 +++++++++ > scripts/Makefile.lib | 7 ++++ > scripts/Makefile.thinlto | 40 ++++++++++++++++++ > scripts/Makefile.vmlinux_a | 83 ++++++++++++++++++++++++++++++++++++++ > scripts/mod/modpost.c | 15 +++++-- > 7 files changed, 174 insertions(+), 17 deletions(-) > create mode 100644 scripts/Makefile.thinlto > create mode 100644 scripts/Makefile.vmlinux_a Overall, this seems reasonable from a high level perspective. I have been testing it with my arm64 and x86_64 distribution configurations for the past couple of days and I have not noticed any issues. Did you take a look at the robot report from patch 2? https://lore.kernel.org/202511052257.Bb85ptQG-lkp@intel.com/ It seems like it could be caused by different optimizations? I plan to take a more in-depth look at the implementation after I am back home from Plumbers in a couple of weeks (just to make sure I understand it from a maintainer's perspective). Based on that, I will either apply it to kbuild-next for 6.20/7.0 or ask for further interations, while still aiming to get it into that release. Cheers, Natha