The 100%cpu and black screen also happens when grub waits for input. So if you have an unclean shutdown, and grub waits indefinately for input before booting, you're stuck.
A workaround is to temporarily work over vnc, get a clean shutdown, then you can boot over spice.
The 100%cpu and black screen also happens when grub waits for input. So if you have an unclean shutdown, and grub waits indefinately for input before booting, you're stuck.
A workaround is to temporarily work over vnc, get a clean shutdown, then you can boot over spice.
Obviously this is not nice.