dkms build failure - Ubuntu 16.04 kernel 4.4.0-161-generic

[Jason A. Donenfeld]

Thanks for the report. Ubuntu's kernel team made an error in
backporting a patch from mainline. They're aware of this error, but
they're unable to rectify it for another 7 weeks, which clearly isn't
an acceptable amount of downtime for WireGuard servers. So yesterday
we made a new WireGuard release that works around this issue. Then,
this morning, Egbert, the maintainer of our Ubuntu package, published
a new Ubuntu package for our new release. So you should be all set by
running `apt update && apt upgrade`. Sorry for the hassle. I'm not too
happy about this situation myself, and I'm going to try to figure out
how the Ubuntu kernel people can make sure they don't break WireGuard
in the future with some sort of CI.