Subject: Re: [PATCH net] net: vlan: sync VLAN features with lower device

From: Jakub Kicinski <[email-masked]>
Date: Thu, 23 Oct 2025 06:55:17 -0700

On Thu, 23 Oct 2025 15:39:07 +0200 Paolo Abeni wrote:
> > @@ -193,6 +193,8 @@ int register_vlan_dev(struct net_device *dev, struct netlink_ext_ack *extack)
> >  	vlan_group_set_device(grp, vlan->vlan_proto, vlan_id, dev);
> >  	grp->nr_vlan_devs++;
> >  
> > +	netdev_change_features(dev);  
> 
> Is this just for NETIF_F_LRO? it feels a bit overkill for single flag.
> Also, why netdev_change_features() (vs netdev_update_features())?

Another thought -- isn't this a problem for more uppers?
Isn't this what all callers of netdev_upper_dev_link() effectively
need, and therefore perhaps we should stick it somewhere in the core
(netdev_upper_dev_link() itself or when device is registered) ?