Re: [PATCH net-next v3 1/2] net: dsa: untag the bridge pvid from rx skbs

[Vladimir Oltean]

On Wed, Sep 23, 2020 at 03:59:46PM -0700, Florian Fainelli wrote:
> On 9/23/20 3:58 PM, Vladimir Oltean wrote:
> > On Wed, Sep 23, 2020 at 03:54:59PM -0700, Florian Fainelli wrote:
> >> Not having much luck with using  __vlan_find_dev_deep_rcu() for a reason
> >> I don't understand we trip over the proto value being neither of the two
> >> support Ethertype and hit the BUG().
> >>
> >> +       upper_dev = __vlan_find_dev_deep_rcu(br, htons(proto), vid);
> >> +       if (upper_dev)
> >> +               return skb;
> >>
> >> Any ideas?
> > 
> > Damn...
> > Yes, of course, the skb->protocol is still ETH_P_XDSA which is where
> > eth_type_trans() on the master left it.
> 
> proto was obtained from br_vlan_get_proto() a few lines above, and
> br_vlan_get_proto() just returns br->vlan_proto which defaults to
> htons(ETH_P_8021Q) from br_vlan_init().
> 
> This is not skb->protocol that we are looking at AFAICT.

Ok, my mistake. So what is the value of proto in vlan_proto_idx when it
fails? To me, the call path looks pretty pass-through for vlan_proto.