I've tested the most recent kernel from Michael Young
http://koji.fedoraproject.org/koji/taskinfo?taskID=2598434
kernel vmlinuz-2.6.37-0.1.rc1.git8.xendom0.fc14.x86_64(rc1.git8 + xen-next.patch)
as Dom0 kernel under Xen 4.0.1 on top of F14.
Attempt to work with NFS remote folder results kernel crash again
- unable to handle paging request and stack trace.
Kernel works OK only as vanilla.
Boris.
P.S. Same issue is in place for PV DomU running
kernel vmlinuz-2.6.37-0.1.rc1.git8.xendom0.fc14.x86_64