Hi Chaudron, thanks for your reply. Considerthe following scenario:

- set a net device alias name (such as *enpxx*) into ovs.

- |OVS_VPORT_CMD_NEW -> ||dev_get_by_name can query the net device using *enpxx* name, but the dev->name that return is *ensxx* name. the |net_device|struct including: ``` |struct net_device {
        char                    name[IFNAMSIZ];
        RH_KABI_REPLACE(struct hlist_node name_hlist,
                        struct netdev_name_node *name_node)
...
|``` name_hlist include enpxx and ensxx name and both of them point to the same net_device, the net_device's name is ensxx. So when using *enpxx* name to query net device, the ||net device's name that return is *ensxx* name.|
Then, openvswitch.ko will save the net device that name is*ensxx*  to a hash 
table. So this will cause the below process:
- ovs can'tobtain the enpxx net device by |OVS_VPORT_CMD_GET.|
-|dpif_netlink_port_poll will get a |notification after |OVS_VPORT_CMD_NEW|, 
but the vport's name is ensxx. ovs will query the ensxx net device from 
interface table, but nothing. So ovs will run the port_del operation.
- this will cause|OVS_VPORT_CMD_NEW|  and OVS_VPORT_CMD_DEL operation to run 
repeatedly.
So the above issue can be avoided by the patch.

在 4/15/24 18:04, Eelco Chaudron 写道:

On 13 Apr 2024, at 10:48, jun.gu wrote:

Check vport name from dev_get_by_name, this can avoid to add and remove
NIC repeatedly when NIC rename failed at system startup.

Signed-off-by: Jun Gu<jun...@easystack.cn>
---
  net/openvswitch/vport-netdev.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/openvswitch/vport-netdev.c b/net/openvswitch/vport-netdev.c
index 903537a5da22..de8977d7f329 100644
--- a/net/openvswitch/vport-netdev.c
+++ b/net/openvswitch/vport-netdev.c
@@ -78,7 +78,7 @@ struct vport *ovs_netdev_link(struct vport *vport, const char 
*name)
        int err;

        vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), name);
-       if (!vport->dev) {
+       if (!vport->dev) || strcmp(name, ovs_vport_name(vport)) {
Hi Jun, not sure if I get the point here, as ovs_vport_name() translates into 
vport->dev->name.

So are we trying to catch the interface rename between the dev_get_by_name(), 
and the code below? This rename could happen at any other place, so this check 
does not guarantee anything. Or am I missing something?

                err = -ENODEV;
                goto error_free_vport;
        }
--
2.25.1

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