From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sedat Dilek Subject: Re: [PATCH 00/22] add support for Clang LTO Date: Sun, 12 Jul 2020 10:59:17 +0200 Message-ID: References: <20200624203200.78870-1-samitolvanen@google.com> <671d8923-ed43-4600-2628-33ae7cb82ccb@molgen.mpg.de> Reply-To: sedat.dilek@gmail.com Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <671d8923-ed43-4600-2628-33ae7cb82ccb@molgen.mpg.de> Sender: linux-kernel-owner@vger.kernel.org To: Paul Menzel Cc: 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 List-Id: linux-arch.vger.kernel.org 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. > > [=E2=80=A6] > > 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=3Dlto [2] https://lore.kernel.org/patchwork/project/lkml/list/?series=3D&submitte= r=3D19676 [3] https://lore.kernel.org/patchwork/series/450026/mbox/ From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39114 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725765AbgGLI7a (ORCPT ); Sun, 12 Jul 2020 04:59:30 -0400 MIME-Version: 1.0 References: <20200624203200.78870-1-samitolvanen@google.com> <671d8923-ed43-4600-2628-33ae7cb82ccb@molgen.mpg.de> In-Reply-To: <671d8923-ed43-4600-2628-33ae7cb82ccb@molgen.mpg.de> Reply-To: sedat.dilek@gmail.com From: Sedat Dilek Date: Sun, 12 Jul 2020 10:59:17 +0200 Message-ID: Subject: Re: [PATCH 00/22] add support for Clang LTO Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Sender: linux-arch-owner@vger.kernel.org List-ID: To: Paul Menzel Cc: 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 Message-ID: <20200712085917.qIPf4j9arPftJNRui_XpnjTQcDH9jMr2Mj2s6TBuQZE@z> 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. > > [=E2=80=A6] > > 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=3Dlto [2] https://lore.kernel.org/patchwork/project/lkml/list/?series=3D&submitte= r=3D19676 [3] https://lore.kernel.org/patchwork/series/450026/mbox/