CentOS 5.2 dom0 w/fairly recent updates on x86_64, xen 3.2.0 RPM
    from xensource recompiled for x86_64, Win 2k3 domU (with GPL PV
    drivers).
    With HVM, phy: disks on LVs won't work, although the same host has
    many PV CentOS hosts running no problem from LVs.  The file: disks
    work with no problems.  The disk configurations I've tried:
    Neither works:
      disk =  [ 'phy:domU/w2k30.root,ioemu:hda,w' ]
      disk =  [ 'phy:domU/w2k30.root,hda,w' ]
      Selected logs:
      [2008-12-19 12:00:11 3365] INFO (XendDomainInfo:1504)
    createDevice: vbd : \
          {'uuid': 'dada2695-5fdd-85c9-3990-8d1978a35782', 'bootable':
    1, 'driver': 'ioemu', \
          'dev': 'ioemu:hda', 'uname': 'phy:domU/w2k30.root', 'mode': 'w'}
      [2008-12-19 12:00:12 3365] INFO (XendDomainInfo:1273) Domain has
    shutdown: name=w2k30 id=63 reason=poweroff.
    Works:
      disk  =  [ 'file:/d/distro.w2k3/w2k30.root,hda,w', ]
      disk  =  [ 'tap:aio:/d/distro.w2k3/w2k30.root,hda,w' ]
      Selected logs:
      [2008-12-19 12:05:15 3365] INFO (XendDomainInfo:1504)
    createDevice: tap : \
          {'bootable': 1, 'uname':
    'tap:aio:/d/distro.w2k3/w2k30.root', 'mode': 'w', 'dev': '\
          hda', 'uuid': 'ee5b79fa-2286-dcab-9864-21af8fce8a8e'}
    With the phy: disk, the host will begin to boot, but then
    immediately shut down.  The phy: disk image was created by dding
    the file from the installed file: image into the blank phy: LV.
    If booted from the win2k3 install CD (cdrom specified as file:,
    disk as phy:), the install hangs forever at "Setup is starting
    Windows", presumably as it's trying to grok the hard drive
    configuration.
    I managed to get the domain to pause during the Plex86/Bocks Bios,
    and see the disk detection as follows:
      ata0 master: QEMU HARDDISK ATA-7 Hard-Disk (   0 MBytes)
      ata0  slave: Unknown device
      Booting from Hard Disk...
    At this point the domain shuts down.
    More information:
      [root@xen-3 distro.w2k3]# lvs /dev/domU/w2k30.root
        LV         VG   Attr   LSize Origin Snap%  Move Log Copy%  Convert
        w2k30.root domU -wi-a- 5.19G
      [root@xen-3 distro.w2k3]# fdisk -l /dev/domU/w2k30.root
      Disk /dev/domU/w2k30.root: 5570 MB, 5570035712 bytes
      255 heads, 63 sectors/track, 677 cylinders
      Units = cylinders of 16065 * 512 = 8225280 bytes
                     Device Boot      Start         End      Blocks      Id  System
      /dev/domU/w2k30.root1   *           1         660     5301418+      7  HPFS/NTFS
    Complete config file follows.  Let me know what else I can provide
    to debug this problem.  Thanks-
      John
    #
    # xen configfile for host 
w2k30.bt1.ablesky.com