Fill out:
https://www.whonix.org/wiki/Advanced_Security_Guide#KVM
Similar to:
https://www.whonix.org/wiki/Advanced_Security_Guide#VirtualBox
Generic link:
https://www.whonix.org/wiki/Advanced_Security_Guide#Spoof_the_Initial_Virtual_Hardware_Clock_Offset
(biossystemtimeoffset)