Re: [PATCH 00/22] add support for Clang LTO
From: Nathan Chancellor <hidden>
Date: 2020-07-12 18:40:54
Also in:
linux-arch, linux-pci, lkml
On Sun, Jul 12, 2020 at 10:59:17AM +0200, Sedat Dilek wrote:
On Sat, Jul 11, 2020 at 6:32 PM Paul Menzel [off-list ref] wrote:quoted
Dear Sami, Am 24.06.20 um 22:31 schrieb Sami Tolvanen:quoted
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 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel