Kernel release status
My own favorite 'small detail under the hood' happens to be Andy Lutomirski's new virtually mapped kernel stack allocations. They make it easier to find and recover from stack overflows, but the effort also cleaned up some code, and added a kernel stack mapping cache to avoid any performance downsides." The virtually mapped kernel stack work was covered here in June.
Stable updates:
4.8.2,
4.7.8, and
4.4.25 were released on October 16.
The relatively small
4.8.3,
4.7.9, and
4.4.26 updates are in the review process as
of this writing; they can be expected on or after October 21.