From 3b5a24866bf5fae387de70be8cb65e29b31a3a6d Mon Sep 17 00:00:00 2001
From: liumengqiu <[email protected]>
Date: Thu, 11 Aug 2022 20:04:09 +0800
Subject: [PATCH 10/22] virNetDevOpenvswitchUpdateVlan: fix vlan tag update
 error

We try to update vlan tag by running virsh update-device command,
libvirtd will report ovs-vsctl arguments error. Vlan tag update
funtion does't consider the xml with no vlan configured circumstances.

The steps to reproduce the problem:
1 define and start domain with its vlan configured as:
    <interface type='bridge'>
      <mac address='52:54:00:9e:bb:ac'/>
      <source bridge='ovs-br0'/>
      <vlan>
        <tag id='10'/>
      </vlan>
      <virtualport type='openvswitch'>
      </virtualport>
      <target dev='vnet4.0'/>
      <model type='virtio'/>
      <driver name='vhost'/>
    </interface>
2 define and run virsh update-device command with no vlan configured as:
    <interface type='bridge'>
      <mac address='52:54:00:9e:bb:ac'/>
      <source bridge='ovs-br0'/>
      <virtualport type='openvswitch'>
      </virtualport>
      <target dev='vnet4.0'/>
      <model type='virtio'/>
      <driver name='vhost'/>
    </interface>
   #virsh update-device dom-id novlan.xml
3 virsh command returned error, and we got an error in libvirtd.log:
  error : virCommandWait:2584 : internal error: exit status 1: ovs-vsctl: 'set' command requires at least 3 arguments
  . Child process (ovs-vsctl --timeout=5 -- --if-exists clear Port vnet4.0 tag -- --if-exists clear Port vnet4.0 trunk
  -- --if-exists clear Port vnet4.0 vlan_mode -- --if-exists set Port vnet4.0) unexpected
  error : virNetDevOpenvswitchUpdateVlan:540 : internal error: Unable to set vlan configuration on port vnet4.0

Signed-off-by: Tu Qiang <[email protected]>
Signed-off-by: Yi Wang <[email protected]>
Reviewed-by: Michal Privoznik <[email protected]>
---
 src/util/virnetdevopenvswitch.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/util/virnetdevopenvswitch.c b/src/util/virnetdevopenvswitch.c
index f961777411..5de8c7f5cf 100644
--- a/src/util/virnetdevopenvswitch.c
+++ b/src/util/virnetdevopenvswitch.c
@@ -547,8 +547,10 @@ int virNetDevOpenvswitchUpdateVlan(const char *ifname,
     virCommandAddArgList(cmd,
                          "--", "--if-exists", "clear", "Port", ifname, "tag",
                          "--", "--if-exists", "clear", "Port", ifname, "trunk",
-                         "--", "--if-exists", "clear", "Port", ifname, "vlan_mode",
-                         "--", "--if-exists", "set", "Port", ifname, NULL);
+                         "--", "--if-exists", "clear", "Port", ifname, "vlan_mode", NULL);
+
+            if (virtVlan && virtVlan->nTags > 0)
+                       virCommandAddArgList(cmd, "--", "--if-exists", "set", "Port", ifname, NULL);
 
     if (virNetDevOpenvswitchConstructVlans(cmd, virtVlan) < 0)
         return -1;
-- 
2.33.0