I have followed the instructions in 
http://wiki.xensource.com/xenwiki/XenParavirtOps / 
Using 
Xen/paravirt_ops
Building with
 domU support 
exactly ..
   1. Get a current kernel. The latest 
kernel.org kernel is generally a good choice.
   Done
   2. Configure as normal; you can start with your current .config file
   Done
   3. If building 32 bit kernel make sure you have CONFIG_X86_PAE enabled (which is set by selecting CONFIG_HIGHMEM64G)
   CONFIG_HIGHMEM64G=y,CONFIG_X86_PAE=y 
   Done 
          * non-PAE mode doesn't work in 2.6.25, and has been dropped altogether from 2.6.26 and newer kernel versions. 
   4. Enable these core options:
         1. CONFIG_PARAVIRT_GUEST
         Done - CONFIG_PARAVIRT_GUEST=y
         2. CONFIG_XEN 
         Done - CONFIG_XEN=y
   5. And Xen pv device support
         1. CONFIG_HVC_DRIVER and CONFIG_HVC_XEN
         Done - CONFIG_HVC_DRIVER=y
         Done - CONFIG_HVC_XEN=y        
         2. CONFIG_XEN_BLKDEV_FRONTEND
         Done - CONFIG_XEN_BLKDEV_FRONTEND=y
         3. CONFIG_XEN_NETDEV_FRONTEND 
         Done - CONFIG_XEN_NETDEV_FRONTEND=y
   6. And build as usual 
      make oldconfig, make -j2 bzImage modules , make -j2 modules_install , make install 
On Tue, Mar 30, 2010 at 10:55 PM, Konrad Rzeszutek Wilk 
<konrad.wilk@xxxxxxxxxx> wrote:
On Tue, Mar 30, 2010 at 10:39:03PM +0530, Onkar Mahajan wrote:
> On Tue, Mar 30, 2010 at 10:33 PM, Joseph Coleman <
> 
joe.coleman@xxxxxxxxxxxxxxxxxx> wrote:
>
> >  Hate to ask but I assume your booting from the XEN Kernel and are using
> > an account with the appropriate permissions to run Xend?
> >
> Yes,  this is latest xen ( compiled from git clone git://
> 
git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen.git linux-2.6-xen ) and I
> am running under root
> privileges.
 I think you are confusing Linux pvops from the git tree above and Xen. There are two seperate
products.
Look at http://wiki.xensource.com/xenwiki/XenParavirtOps
and pay especailly attention in the grub line. You NEED xen.gz in it.