Kernel 3.14.5-200.fc20.x86_64 won't boot: module problem

[Patrick O'Callaghan]

On trying to boot the above kernel, I get a "Failed to start Load Kernel
Modules" error. This appears to be caused by missing vboxdrv modules
(from VirtualBox). Booting an earlier kernel works fine.

Two comments:

1) I thought DKMS was supposed to rebuild the VBox modules for each new
kernel automatically. This has happened in the past but seems to have
failed now. Why would this be and how can I fix it?

2) The error message was unhelpful as it didn't identify which modules
failed. It took some searching to find what the problem was. Surely this
could be done better. (In fact I'd argue that failing to load these
modules shouldn't result in a failed boot, but I realize that's maybe
harder to deal with).

poc