Hi nony
I have a similar problem that seems to be an upstream problem with systemd.
https://bugs.freedesktop.org/show_bug.cgi?id=70593
So I must wait...or not...
For a work-a-round I changed the default start and stop timeout to 10 seconds (default is 90). Located in:
/etc/systemd/system.conf
These two lines now read:
DefaultTimeoutStartSec=10s
DefaultTimeoutStopSec=10s
This works for me until a fix comes out. A slower computer could require more time.