.. let's see how much, if anything, breaks due to the version number.
Probably less than during the 3.0 timeframe, but I can just imagine
somebody checking for meaningful versions.

Because the people have spoken, and while most of it was complete
gibberish, numbers don't lie. People preferred 4.0, and 4.0 it shall
be. Unless somebody can come up with a good argument against it.

So far, the arguments against it seem to have been "major numebr
should go with a major new feature or breaking of compatibility",
which just shows how little people know. We don't break compatibility,
and we haven't done feature-based releases since basically forever.

On the other hand, the strongest argument for some people advocating
4.0 seems to have been a wish to see 4.1.15 - because "that was the
version of Linux skynet used for the T-800 terminator".

So on the whole, I wouldn't read too much into the number.

On an actual technical side, this was a *fairly* small release. By
modern standards, that is. It's certainly noticeably smaller than some
recent kernels have been, although we're talking ~9k non-merge commits
rather than 10-11k, so it's not like it's that huge of a difference.

The live patching infrastructure made some news, but my personal
favorite features are actually some vm cleanups, where this release is
getting rid of the largely unused non-linear remapping code (replaced
with just emulating it with lots of smaller mappings) and unifies the
NUMA and PROTNONE handling for page tables.

But nobody should notice. Because moving to 4.0 does *not* mean that
we somehow changed what people see. It's all just more of the same,
just with smaller numbers so that I can do releases without having to
take off my socks again.

Go test it out. The git trees are already out, the tar-ball and
patches are going out as I write this.  Of course, with the version
change, I suspect that there will be *some* hiccup with kernel.org
mirroring, even if Konstantin thinks that the scripts are all ready to
go.. So if you don't find tar-balls and patches, either I screwed up,
or Konstantin did ;)

                              Linus