Why vdsmd service is failing at unified restoration step with error "too many values to unpack"

Issue

• vdsmd service is failing with below error in the supervdsm log.

restore-net::ERROR::2017-07-19 17:11:53,099::vdsm-restore-net-config::478::root::(restore) unified restoration failed.
Traceback (most recent call last):
  File "/usr/share/vdsm/vdsm-restore-net-config", line 473, in restore
    unified_restoration()
  File "/usr/share/vdsm/vdsm-restore-net-config", line 138, in unified_restoration
    classified_conf = _classify_nets_bonds_config(available_config)
  File "/usr/share/vdsm/vdsm-restore-net-config", line 284, in _classify_nets_bonds_config
    current_config = kernelconfig.KernelConfig(NetInfo(netswitch.netinfo()))
  File "/usr/lib/python2.7/site-packages/vdsm/network/netswitch.py", line 298, in netinfo
    _netinfo = netinfo_get(compatibility=compatibility)
  File "/usr/lib/python2.7/site-packages/vdsm/network/netinfo/cache.py", line 124, in get
    return _get(vdsmnets)
  File "/usr/lib/python2.7/site-packages/vdsm/network/netinfo/cache.py", line 65, in _get
    nets_info = _networks_report(vdsmnets, routes, ipaddrs, devices_info)
  File "/usr/lib/python2.7/site-packages/vdsm/network/netinfo/cache.py", line 89, in _networks_report
    report_network_qos(nets_info, devices_info)
  File "/usr/lib/python2.7/site-packages/vdsm/network/netinfo/qos.py", line 42, in report_network_qos
    iface, = host_ports
ValueError: too many values to unpack