2012/12/30 Flavio Leitner [off-list ref]:

The user space teamd daemon may need to control the
master's carrier state depending on the selected mode.

[...]

+static int team_change_carrier(struct net_device *dev, bool new_carrier)
+{
+       if (new_carrier)
+               netif_carrier_on(dev);
+       else
+               netif_carrier_off(dev);
+       return 0;
+}
+

[...]

+       .ndo_change_carrier     = team_change_carrier,

I wonder what else you might put in the .ndo_change_carrier
implementation? It's already the same for dummy device and tunnels
would get more copies. Maybe it would be enough to allocate a bit in
netdev->priv_flags and use that in dev_change_carrier() instead?

Best Regards,
Michał Mirosław