Just installed rawhide yesterday and noticed a kernel panic when in
selinux enforcing mode. I appended selinux=0 and it booted right up. Todays kernel (1884)
did not panic but got stuck on starting udev. Again rebooted with selinux=0 and was fine.
Instead of booting with selinux=0, boot with enforcing=0 and report the
AVC messages. You might need to relabel.