Description of problem: 
  Since i upgraded FC3-->FC4, i cannot boot file-backed xen domUs when selinux
  (targeted policy) is active. 


Version-Release number of selected component (if applicable):
  xen-2-20050522
  selinux-policy-targeted-1.23.18-12
  util-linux-2.12p-9.5


How reproducible:
  always


Steps to Reproduce:
  [setenforce 1]
  xm create $domain-config

  
Actual results:
  [root@crusher ~]# xm create -c bering
  Using config file "/etc/xen/bering".
  Error: Error creating domain: vbd: Segment not found:
    uname=file:/var/bering.ext2

  [root@crusher ~]# dmesg
  # see attachment.


Expected results:
  The domain "bering" boots


Additional info:
  If i want to boot a file backed domain ("disk: ['file:...' ]"), i have two
  workarounds: disabling selinux ("setenforce 0") or changing the domains config
  file from

    disk = [ 'file:/var/bering.ext2,hda1,w' ]
    
  to

    disk = [ 'phy:/dev/loop0,hda1,w' ]

  and doing the "losetup /dev/loop0 /var/bering.ext2" myself before the 
  "xm create". I still get lots of selinux denies, but it nevertheless works,
  including networking.

  As the manual "losetup" failed, too due to selinux denies before i upgraded 
  today to selinux-policy-targeted-1.23.18-12, i thought this is bug #160755,
  but now the manual losetup works while the xend-automated losetup fails. So 
  i set up this bugreport.