Here’s something that wasn’t on my bingo card for this year of the “MKISS” driver for ham radio being modernized in 2026 as opposed to just being dropped. The MKISS code hasn’t seen much driver activity since the original Git import of the Linux kernel more than twenty years ago.
Posted to the Linux kernel mailing list this Sunday by open-source developer Mashiro Chen is modernizing and cleaning up the MKISS ham radio driver. This is a serial port KISS protocol driver for exchanging data between a computer and terminal node computer for AX.25 amateur radio “ham radio” connections.
The MKISS driver has been around since before the Linux kernel Git import and in the 21 years since it was an SMP rewrite in 2025 and some minor fixes but that’s been about it. Even for some minor code maintenance on MKISS has been more than six years ago.
Mashiro Chen explained of this 2026 modernization of the driver:
“This patch series modernizes the mkiss driver, which is used for AX.25 communication over serial lines.
The series starts by moving variable assignments out of ‘if’ conditions to improve code safety and readability. The second patch removes redundant static initializations to 0. The third patch fixes missing spaces around assignment operations. The fourth patch modernizes the logging system by replacing legacy printk() calls with netdev_* and pr_* macros for better device-specific context.
The fifth patch addresses remaining checkpatch.pl issues, primarily converting space-based indentation to tabs, aligning parameters, and fixing comment formats.”
The patches are out for review on the Linux kernel mailing list.