Among the pull requests coming in at the tail end of the Linux 6.15 merge window with 6.15-rc1 expected tonight are all of the Kbuild updates as the infrastructure for building out the kernel.
One of the changes worth mentioning for Kbuild in Linux 6.15 is enhancing the performance of gendwarfksyms. The gendwarfksyms tool was added in Linux 6.14 for helping with the Linux kernel’s Rust ambitions. The gendwarfksyms tool is used to compute CRCs for export symbols based on DWARF information. The tool is being made faster in Linux 6.15 by adding a separate pass to resolve fully-qualified names (FQNs). In doing so the performance of the tool can become a consistent 50%+ faster during a defconfig+Rust kernel build. Even without Rust there can be a 10% improvement in the build time when relying on gendwarfksyms.
The Kbuild changes in Linux 6.15 also add support for the Loong64 (LoongArch 64-bit architecture) Debian GNU/Linux.
Some other Kbuild changes include support for relative paths to source files for better reproducibility, Kbuild bash completion, and an intermediate vmlinux.unstripped for architectures that need static relocations removed from the final vmlinux image. Lastly there is also debuginfo support now available for the RPM package build of the Linux kernel.
More details on all of the Kbuild changes for Linux 6.15 via this pull request.
