> > > > > >    How about the code below instead?
> > > > > > 
> > > > > > 	if (netif_running(ndev))
> > > > > > 		ravb_close(ndev);
> > > > > > 
> > > > > >  	ndev->mtu = new_mtu;
> > > > > > 	netdev_update_features(ndev);
> > > > > 
> > > > > Is there a need to call netdev_update_features() even if the if is not 
> > > > > running?
> > > > 
> > > > In my testing, it didn't seem so.
> > > 
> > > That may be because your testing doesn't cover cases where it would make
> > > any difference.
> > 
> > Cases other than changing the MTU while the device is up?
> 
> I was thinking of cases where listeners are registered for the
> notifier that netdev_update_features() triggers.

Where are we here? Is this a blocker?