[Fedora-xen] NFS Booting - Kernel modification

[Abhishek Gaurav]

Hi,
I have been trying to boot a VM over NFS with the default xen-kernel 
that came with FC6. However, I ran into the problems like:

md: Autodetecting RAID arrays.
md: autorun ...
md: ... autorun DONE.
VFS: Cannot open root device "nfs" or unknown-block(0,255)
Please append a correct "root=" boot option
Kernel panic - not syncing: VFS: Unable to mount root fs on 
unknown-block(0,255)

After some search, it looks like that the CONFIG_IP_PNP and 
CONFIG_ROOT_NFS parameters need to be enabled in the kernel. Can anyone 
please let me know how to go about it in the default fc6-xen system. It 
also looks like that I do not have the source for the xen-enabled kernel.

Thanks,
Abhishek.