I installed FC16 on a system that has an Asus P8B WS board and a Xeon E3 CPU. This system boots via (U)EFI.

Everything works well but I want to use Xen so I installed the binaries using yum. It put down files but did not setup anything in GRUB. Following some advice, I added the information but it does not boot via /boot/xen.gz because, I assume, it's not an EFI binary. The installation did not include an EFI-compatible binary.

Pulling down the Xen source and compiling it gave me an EFI executable.

Unfortunately, I don't know how to use this with GRUB. I tried using efibootmgr which created another EFI boot entry but it doesn't have any of the configuration details that you'd normally see in a grub.conf file.

http://wiki.xensource.com/xenwiki/XenParavirtOps has info about Xen/EFI but I don't have (I think) an EFI shell so I cannot test it as described.

Thanks and cheers,

Mark