On Fri, Sep 18, 2020 at 1:50 PM Sami Tolvanen <samitolvanen@xxxxxxxxxx> wrote: > > On Fri, Sep 18, 2020 at 1:22 PM Sedat Dilek <sedat.dilek@xxxxxxxxx> wrote: > > > > On Fri, Sep 18, 2020 at 10:14 PM 'Sami Tolvanen' via Clang Built Linux > > <clang-built-linux@xxxxxxxxxxxxxxxx> wrote: > > > > > > 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 has shipped millions of Pixel devices running three > > > major kernel versions with LTO+CFI 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 patches 1-5 are not directly related to LTO, but are > > > needed to compile LTO kernels with ToT Clang, so I'm including them > > > in the series for your convenience: > > > > > > - Patches 1-3 fix build issues with LLVM and they are already in > > > linux-next. > > > > > > - Patch 4 fixes x86 builds with LLVM IAS, but it hasn't yet been > > > picked up by maintainers. > > > > > > - Patch 5 is from Masahiro's kbuild tree and makes the LTO linker > > > script changes much cleaner. > > > > > > > Hi Sami, > > > > might be good to point to your GitHub tree and corresponding > > release-tag for easy fetching. > > Ah, true. You can also pull this series from > > https://github.com/samitolvanen/linux.git lto-v3 Also, I've been using b4 happily for a short while now. https://people.kernel.org/monsieuricon/introducing-b4-and-patch-attestation My workflow would be: check lore.kernel.org/lkml/ for the series in question. In this case: https://lore.kernel.org/lkml/CABCJKueyWvNB2MQw_PCLtZb8F1+sA1QOLJi_5qMKwdFCcwSMGg@xxxxxxxxxxxxxx/T/#t is the cover letter. Then in my tree: $ b4 am https://lore.kernel.org/lkml/CABCJKueyWvNB2MQw_PCLtZb8F1+sA1QOLJi_5qMKwdFCcwSMGg@xxxxxxxxxxxxxx/T/#t -o - | git am -- Thanks, ~Nick Desaulniers
