As was pointed out to us stable kernel maintainers last week, the overflow of the .y release number was going to happen soon, and our proposed solution for it (use 16 bits instead of 8), turns out to be breaking a userspace-visable api.
As we can’t really break this, I did a release of the 4.4.256 and 4.9.256 releases today that contain nothing but a new version number. See the links for the full technical details if curious.
Right now I’m asking that everyone who uses these older kernel releases
to upgrade to this release, and do a full rebuild of their systems in
order to see what might, or might not, break. If problems happen,
please let us know on the stable@vger.kernel.org mailing list as soon
as possible as I can only hold off on doing new stable releases for
these branches for a single week only (i.e. February 12, 2021).