vboxdrv não existe. após a instalação do kernel

Question

Eu instalei o kernel 4.12.0-041200rc4-genérico, e desde então quando eu abro o Virtual Box eu recebo isso

root@machine:~# virtualbox 
WARNING: The character device /dev/vboxdrv does not exist.
     Please install the virtualbox-dkms package and the appropriate
     headers, most likely linux-headers-generic.

     You will not be able to start VMs until this problem is fixed.

Tentamos corrigi-lo e entender o seguinte:

root@machine:~# aptitude install linux-headers-generic virtualbox-dkms 
linux-headers-generic is already installed at the requested version (4.4.0.78.84)
virtualbox-dkms is already installed at the requested version (5.0.40-dfsg-0ubuntu1.16.04.1)
linux-headers-generic is already installed at the requested version (4.4.0.78.84)
virtualbox-dkms is already installed at the requested version (5.0.40-dfsg-0ubuntu1.16.04.1)
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B of archives. After unpacking 0 B will be used.

Adivinhei que eu precisava instalar a versão genérica do linux-headers 4.12

root@machine:~# aptitude install linux-headers-$(uname -r)
linux-headers-4.12.0-041200rc4-generic is already installed at the requested version (4.12.0-041200rc4.201706042031)
linux-headers-4.12.0-041200rc4-generic is already installed at the requested version (4.12.0-041200rc4.201706042031)
No packages will be installed, upgraded, or removed.
0 packages upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
Need to get 0 B of archives. After unpacking 0 B will be used.