June 2026 (zephyrproject-rtos/zephyr): Implemented mutex initialization and usage safety enhancements to harden synchronization primitives, preventing use-after-init and re-init scenarios, with sentinel-based validation, CONFIG_ASSERT guards, and improved test coverage. This work reduces risk of deadlocks and undefined behavior in concurrent tasks and improves debuggability in the Zephyr kernel.

April 2026: TLS Stabilization for RISC-V in Zephyr4Microchip/zephyr. Fixed early TLS initialization to establish the thread pointer before any C code executes and implemented saving/restoring of callee-saved registers per ABI. Included refinements to TLS initialization and TLS variable handling to improve stability and correctness. Two commits drive the change: 2d6bdab5dc038881052ec2804e38713160782be9 and f94efe2607e617ea9c380d9f315051d8aa9c2997, addressing TLS setup and canary patch hygiene.

March 2026 — Zephyr TLS-based stack canary hardening for RISC-V and boot-time safety. Implemented per-thread stack canaries, adjusted TLS layout, and boot sequence to ensure safety and reliability in early initialization. Reduced risk of stack canary faults during early boot; provided clear guidance for compiler-generated canary access and TLS initialization.