Hmm.. somehow i am getting this now. Haven't changed any config of xen, and i am in /root, so why it should show that message.
xm list Error: (9, 'Bad file descriptor') Usage: xm list [options] [Domain, ...]
List information about all/some domains. -l, --long Output all VM details in SXP --label Include security labels --state=<state> Select only VMs with the specified state