+%if %{?openvswitch_version:0}%{!?openvswitch_version:1}
+%define openvswitch_version 1.5.90
+%endif
+
+%if %{?kernel_name:0}%{!?kernel_name:1}
+%define kernel %(rpm -qa 'kernel*xen-devel')
+%define kernel_name %(rpm -q --queryformat "%%{Name}" %{kernel} | sed 's/-devel//' | sed 's/kernel-//')
+%define kernel_version %(rpm -q --queryformat "%%{Version}-%%{Release}" %{kernel})
+%define kernel_flavor xen
+%endif
+