When the peer link is created, its "iflink" information is not
advertised through Netlink. Once created, the local device is advertised
with this information but if a user is maintaining a cache from all
updates, it will still miss the iflink for the peer link:
2: veth0@NONE: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group
default
link/ether ae:0e:08:af:fb:a0 brd ff:ff:ff:ff:ff:ff
3: veth1@veth0: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN
group default
link/ether 3a:31:f1:36:2e:e5 brd ff:ff:ff:ff:ff:ff
With this patch, we advertise again the peer link to let any user pick
the appropriate iflink information:
3: veth0@NONE: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group
default
link/ether fa:ba:12:26:99:00 brd ff:ff:ff:ff:ff:ff
3: veth0@veth1: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group
default
link/ether fa:ba:12:26:99:00 brd ff:ff:ff:ff:ff:ff
4: veth1@veth0: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN
group default
link/ether ea:e4:e2:26:3c:87 brd ff:ff:ff:ff:ff:ff
Signed-off-by: Vincent Bernat <vinc...@bernat.im>
---
v3:
- send an additional netlink messages once the peer link is tied to
avoid any chicken/egg problem
v2:
- ensure the device is unregistered in case of link configuration failure
drivers/net/veth.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/drivers/net/veth.c b/drivers/net/veth.c
index f37a6e61d4ad..2376d17b8f53 100644
--- a/drivers/net/veth.c
+++ b/drivers/net/veth.c
@@ -466,6 +466,8 @@ static int veth_newlink(struct net *src_net, struct
net_device *dev,
priv = netdev_priv(peer);
rcu_assign_pointer(priv->peer, dev);
+
+ rtmsg_ifinfo(RTM_NEWLINK, peer, IFF_SLAVE, GFP_KERNEL);
return 0;
err_register_dev:
--
2.8.1
