On August 7, five Linux LTS kernel stable releases were announced, including versions 5.10.264, 5.15.215, 6.1.182, 6.6.150, and 6.12.102, all featuring a hardened Safe-RET mitigation for AMD processors affected by a subtle interrupt-injection flaw. The patch, developed by AMD's Borislav Petkov and others, introduces an LFENCE and a routine to manage register states, preventing speculative execution from leaking kernel data during interrupts. Initial attempts to implement the fix faced reverts due to its complexity, but it has now been successfully integrated into the kernel, specifically targeting systems with CONFIG_MITIGATION_SRSO enabled. Users with AMD EPYC or Ryzen processors are encouraged to update their systems promptly, as the patch does not affect ARM and RISC-V architectures
Linux LTS Kernel 5.10.264, 5.15.215, 6.1.182, 6.6.150, and 6.12.102 Drop: Hardened Safe-RET Fix for AMD SRSO
Five Linux LTS kernel stable releases landed August 7, all shipping a hardened Safe-RET mitigation to plug a subtle interrupt-injection flaw in SRSO-affected AMD processors. The patch, led by AMD's Borislav Petkov, adds an LFENCE and a register-state adjustment routine to prevent speculative execution from leaking kernel data when interrupts occur mid-sequence. Initial attempts to land the fix in the 5.10 and 5.15 trees were immediately reverted, highlighting just how tricky the edge case proved for stable maintainers. The vulnerability requires local code execution and carries minimal performance overhead, so systems with CONFIG_MITIGATION_SRSO enabled should update as soon as their distros push the new kernels.
