Released about three months ago, Linux kernel 5.12 introduced lots of goodies, including support for Playstation 5 DualSense and Nintendo 64 game controllers, eMMC inline encryption support, support for the Lenovo IdeaPad platform profile and the Lenovo ThinkPad X1 Tablet Gen 2, as well as a new memory-debugging tool called KFENCE.
It also introduced initial support for zoned block devices to the Btrfs file system, LTO in Clang support, AMDGPU Freesync HDMI support, and many other cool features, but it’s now marked as EOL (End of Life) on the kernel.org website, which means that it will no longer receive support upstream and that you must upgrade to a newer or LTS kernel as soon as possible.