Comment # 24 on bug 1200461 from Thomas Blume

(In reply to Mike DeMicco from comment #23)
> There probably is some incompatibility with my hardware. I do believe the
> computer is functioning properly as I've not had any other problems other
> than this issue. 
> 
> As mentioned above, I tried generating a new initrd with my old kernel, and
> got the system freeze too.

To find out more, could you please enable udev debug logging in:

/etc/udev/udev.conf

?
Afterwards, please reboot and reproduce the issue.
Hopefully that will give some useful log output in the systemd journal.