Rust Binder, faster kbuild, BPF RV dispute

Kernel traffic centered on retiring the C Binder driver for its Rust successor, a large kbuild speedup series, and a heated nack over BPF-based runtime verification monitors. Memory management drain cleanups, a BPF trampoline use-after-free fix, expanded BPF calling conventions, and PCI liveupdate support also advanced.

C Binder driver proposed for removal

A patch on the rust-for-linux list proposes deleting the long-standing C Binder driver after the Rust version reaches feature parity and Android deployment. The change would leave the Rust implementation as the sole in-tree Binder. Android and IPC subsystem maintainers have direct reason to track the transition.

kbuild series claims large build speedups

A 23-patch kbuild series aims for up to 36 percent faster allmodconfig builds through parallelization and Kconfig caching. Linus Torvalds and eleven other participants are discussing the work on linux-kernel. Anyone iterating large kernel configurations stands to gain from shorter rebuild cycles.

Nack on BPF monitors for runtime verification

An RFC series adding BPF-based pluggable monitors for runtime verification drew a nack from Alexei Starovoitov on the bpf list. The author and Steven Rostedt defended domain-specific use cases in a heated exchange. The dispute will determine how tightly RV couples to the BPF stack.

Folio batches cut most lru_add_drain calls

Hugh Dickins posted a v2 mm series that removes most lru_add_drain and lru_add_drain_all calls by letting folios stay on per-cpu fbatches with PG_lru set. The approach simplifies paths that previously forced expensive drains. Memory management developers should watch for lower drain overhead on hot allocation paths.

BPF trampoline use-after-free fix

A v2 BPF series fixes a use-after-free of programs detached from busy trampolines through nop-skip patching and adds a KASAN-triggering selftest. The change closes a lifetime hole in the trampoline path. BPF and security reviewers have a clear stake in seeing it land.

By-value structs and __int128 land in bpf-next

A v4 series adding verifier and JIT support for by-value structs and __int128 arguments in global functions and kfuncs was applied to bpf-next. The work widens the calling conventions BPF can express for helpers and kfuncs. Authors of richer kfunc interfaces gain more natural argument passing.

PCI liveupdate series applied at v8

The v8 PCI liveupdate series, covering device preservation across kexec, was reviewed and applied to the liveupdate tree by Pasha Tatashin. It forms part of broader live-update infrastructure. Operators seeking lower downtime across kernel updates depend on the PCI pieces integrating cleanly.