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=-9.1 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,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 AEC7BC433DF for ; Sun, 12 Jul 2020 19:01:31 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 014F6206F0 for ; Sun, 12 Jul 2020 19:01:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="N0HHcMjV" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 014F6206F0 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19289-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 7367 invoked by uid 550); 12 Jul 2020 19:01:22 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 1329 invoked from network); 12 Jul 2020 18:40:58 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to; bh=5TJ+34sQAVUrawBXByyfuwrbgj6i1cli/YCTjxtCBqw=; b=N0HHcMjVGeZLZKs6kySBi/kLjx//vGsHRhAgAn70NbsmCWAMm2ggej1XEym1TkTrI2 1RaGmxT5o0gLydjCDJGV76FDHQsG0/MeBmIbxTv5DSaT3TULK/IfbYlfepfNEkiMQmk9 pMxE7Rt2/EFgEH7Quq7GvESDdpvWY+RbR8tRKc/SElrWfewWr1bDfzmOZAel5bastYU4 l+o96BGwta1qZ7PRMbDolq2P/ebYU/wwwO2jQcK/mwQ0tlDCRPQ2vZa/eEBWU7Y6nUZT K+Ku0Xl1nF8NMzl71Sss8yD4qs25ojddZtL3UAw9gfH97kt9dPHm6QwrFWkINM8fPBxh i8Rg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to; bh=5TJ+34sQAVUrawBXByyfuwrbgj6i1cli/YCTjxtCBqw=; b=dq6Cw2mfMU7QyF/UgRORwIzpm7rgf/MqX8cAhIj0gU+oxat53GeauuhxqtBARRlNqh X0Qd5F41GkML0dzUcvpLqRwsaw2sCWhsFIk1r0N+pE5U2fkWBxF/0d3qYZLE5JHJGlVU 3bC+nK82WF4ekMuhkQ7IFDEyPHhFXq8kOaCqYvOerYCn0cxDXaUqymLwRXb44KQ46W4Z X9mmRCi3fzBcdTjskQwCFGxxs7VMLA6mDx3NFJczy/ddsA1Db6dv3bnSwRlSiIcG4LEL bKEfcN1TV6LX8GxHhNz2jcnhBfta6OiZdRPpmwknaIvP/tQ2qCnvkw+VqPVcNXO4iFcL /fcQ== X-Gm-Message-State: AOAM5302WTrisgHQHZboMelO2t1M5k+rG9V1nN5Ax+GtLgFl4XWA6UM5 4BGQzwA6YDEY8E/TqrbVsQU= X-Google-Smtp-Source: ABdhPJwaLeWOxzmuhJhjgAdmI0j3ddtpspQ4OkHVexe7PvXeW20GC370vRPp3GnVrW9KjIJcaky3VQ== X-Received: by 2002:a62:29c6:: with SMTP id p189mr52732155pfp.55.1594579245655; Sun, 12 Jul 2020 11:40:45 -0700 (PDT) Date: Sun, 12 Jul 2020 11:40:41 -0700 From: Nathan Chancellor To: Sedat Dilek Cc: Paul Menzel , Sami Tolvanen , Masahiro Yamada , Will Deacon , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , Nick Desaulniers , Clang-Built-Linux ML , kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH 00/22] add support for Clang LTO Message-ID: <20200712184041.GA1838@Ryzen-9-3900X.localdomain> References: <20200624203200.78870-1-samitolvanen@google.com> <671d8923-ed43-4600-2628-33ae7cb82ccb@molgen.mpg.de> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Sun, Jul 12, 2020 at 10:59:17AM +0200, Sedat Dilek wrote: > On Sat, Jul 11, 2020 at 6:32 PM Paul Menzel wrote: > > > > Dear Sami, > > > > > > Am 24.06.20 um 22:31 schrieb Sami Tolvanen: > > > This patch series adds support for building x86_64 and arm64 kernels > > > with Clang's Link Time Optimization (LTO). > > > > > > In addition to performance, the primary motivation for LTO is to allow > > > Clang's Control-Flow Integrity (CFI) to be used in the kernel. Google's > > > Pixel devices have shipped with LTO+CFI kernels since 2018. > > > > > > Most of the patches are build system changes for handling LLVM bitcode, > > > which Clang produces with LTO instead of ELF object files, postponing > > > ELF processing until a later stage, and ensuring initcall ordering. > > > > > > Note that first objtool patch in the series is already in linux-next, > > > but as it's needed with LTO, I'm including it also here to make testing > > > easier. > > > > […] > > > > Thank you very much for sending these changes. > > > > Do you have a branch, where your current work can be pulled from? Your > > branch on GitHub [1] seems 15 months old. > > > > Agreed it's easier to git-pull. > I have seen [1] - not sure if this is the latest version. > Alternatively, you can check patchwork LKML by searching for $submitter. > ( You can open patch 01/22 and download the whole patch-series by > following the link "series", see [3]. ) > > - Sedat - > > [1] https://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git/log/?h=lto > [2] https://lore.kernel.org/patchwork/project/lkml/list/?series=&submitter=19676 > [3] https://lore.kernel.org/patchwork/series/450026/mbox/ > Sami tagged this series on his GitHub: https://github.com/samitolvanen/linux/releases/tag/lto-v1 git pull https://github.com/samitolvanen/linux lto-v1 Otherwise, he is updating the clang-cfi branch that includes both the LTO and CFI patchsets. You can pull that and just turn on CONFIG_LTO_CLANG. Lastly, for the future, I would recommend grabbing b4 to easily apply patches (specifically full series) from lore.kernel.org. https://git.kernel.org/pub/scm/utils/b4/b4.git/ https://git.kernel.org/pub/scm/utils/b4/b4.git/tree/README.rst You could grab this series and apply it easily by either downloading the mbox file and following the instructions it gives for applying the mbox file: $ b4 am 20200624203200.78870-1-samitolvanen@google.com or I prefer piping so that I don't have to clean up later: $ b4 am -o - 20200624203200.78870-1-samitolvanen@google.com | git am Cheers, Nathan