Comment # 5 on bug 1230010 from Thorsten Kukuk

(In reply to Fabian Vogt from comment #4)
> The error message can be misleading: libmount shows the first mount of the
> source device if the mount syscall returns -EBUSY for whatever reason. In
> this case the most likely reason for that is that /.snapshots is already
> mounted.
> 
> Is this reproducible?

No, it's not. I saw this now during 3 days on two machines, all the other
machines and this ones rebooted without problems the other times.

> When the error happens, is /.snapshots already mounted? If not, what happens
> on systemctl start /.snapshots?

Forgot to check that. At least /.snapshots was mounted after I pressed Ctrl-D
and could login.