ao atualizar o dkms, vejo esta mensagem:
Your system has UEFI Secure Boot enabled.
UEFI Secure Boot is not compatible with the use of third-party drivers.
The system will assist you in toggling UEFI Secure Boot. To ensure that
this change is being made by you as an authorized user, and not by an
attacker, you must choose a password now and then use the same password
after reboot to confirm the change.
If you choose to proceed but do not confirm the password upon reboot,
Ubuntu will still be able to boot on your system but the Secure Boot
state will not be changed.