[vbox-dev] Configure error: kmk (variable KBUILDDIR) not found

[Federico Franzoni]

Hi all,
I'm getting an error when trying to configure the vbox builder:

'
Checking for environment: Determined build machine: linux.amd64, target 
machine: linux.amd64, OK.
Checking for kBuild:
   ** kmk (variable KBUILDDIR) not found!
'

I made the configure step hundreds of times and never had this problem.
I'm working on Fedora 23 64-bit.
I already configured and built vbox on this same machine, and I still 
can, but if I try the configure step it fails as above.

The only thing I can guess is I accidentally removed some package, but I 
can't figure out which one.
I tried searching for a solution online but I found nothing helpful.
Can you please help me?

Thanks,
Federico