https://wccftech.com/amd-rolls-out-linux-update-for-zen-3-processors-with-the-newest-cpu-microcode/

The AMD open-source team has recently published an update to the Family 19h / Zen 3 CPU microcode to the Linux firmware tree on the git.kernel.org site, which is the "repository of firmware blobs for use with the Linux kernel." The firmware update is under the linux-firmware.git tree. The new update is for AMD Zen 3 CPU users operating in Linux.

AMD did not issue a changelog for the newest firmware upgrade, which seems to be pretty standard practice on these types of advancements in Linux. The last update to the Family, 19h CPU microcode, was last November. Still, it is unsure if AMD completed bug patches or security fixes without clarification as to what changes were made to the firmware.