utils_net: also check ip for host up nic

When create linux bridge or macvtap for guest interface to use,
there maybe many UP state host nic, but only the ones with ip can
work.

Signed-off-by: Yanqiu Zhang <[email protected]>

virttest/utils_net.py

@@ -1439,11 +1439,24 @@ def get_net_if(runner=local_runner, state=".*", qdisc=".*", optional=".*"):
     # As the runner converts stdout to unicode on Python2,
     # it has to be converted to string for struct.pack().
     result = str(runner(cmd))
-    return re.findall(
+    ifaces_up = re.findall(
         r"^\d+: (\S+?)[@:].*%s.*%s.*state %s.*$" % (optional, qdisc, state),
         result,
         re.MULTILINE,
     )
+    LOG.debug("The ifaces up on host: %s" % ifaces_up)
+    ifaces_with_ip = []
+    for iface in ifaces_up:
+        cmd = "ip -c=never addr show %s" % iface
+        ret = runner(cmd)
+        ipv4_addr = re.findall("inet (.+?)/..?", ret, re.MULTILINE)
+        if ipv4_addr:
+            ifaces_with_ip.append(iface)
+    LOG.debug("The ifaces up with ip on host: %s" % ifaces_with_ip)
+    if not ifaces_with_ip:
+        LOG.error("No up ifaces with ip on host!")
+    else:
+        return ifaces_with_ip
 
 
 def get_sorted_net_if():