Comment # 19 on bug 1201398 from Stefan Dirsch

Ok. Usually you're supposed to run this program in a terminal on a desktop,
then logout. And once the process catches the logout the process will finish.
Unfortunately now you're in a state where this process never terminates, since
you even cannot start a desktop any longer due to the Xserver crash.

I suggest to run

  prime-select unset

Hopefully the program then give you some hint how to terminate this process. Or
in the worst case try to find it via 'ps' and kill it manually or reboot the
machine. I mean let's find a way to get your system working again in a clean
state, e.g. by removing package suse-prime and install it again and then run

  prime-select intel

Then, when in a desktop with intel only try again

  prime-select nvidia

and logout. Hopefully things then are working. It's hard to debug this from
remote.