# Re: \[RFC PATCH v2 net-next 01/16\] net: dsa: call dsa\_port\_bridge\_join when joining a LAG that is already in a bridge

- From: Tobias Waldekranz \<tobias@waldekranz.com\>
- Date: 2021-03-22 10:25:38 
- List: netdev
- Page: https://ratatoskr.run/netdev/2021/03/6309872
- Thread: https://ratatoskr.run/netdev/2021/03/6306967/t.md

```text
On Fri, Mar 19, 2021 at 01:18, Vladimir Oltean [ref] wrote:
> From: Vladimir Oltean <vladimir.oltean@nxp.com>
>
> DSA can properly detect and offload this sequence of operations:
>
> ip link add br0 type bridge
> ip link add bond0 type bond
> ip link set swp0 master bond0
> ip link set bond0 master br0
>
> But not this one:
>
> ip link add br0 type bridge
> ip link add bond0 type bond
> ip link set bond0 master br0
> ip link set swp0 master bond0
>
> Actually the second one is more complicated, due to the elapsed time
> between the enslavement of bond0 and the offloading of it via swp0, a
> lot of things could have happened to the bond0 bridge port in terms of
> switchdev objects (host MDBs, VLANs, altered STP state etc). So this is
> a bit of a can of worms, and making sure that the DSA port's state is in
> sync with this already existing bridge port is handled in the next
> patches.
>
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> ---

Reviewed-by: Tobias Waldekranz <tobias@waldekranz.com>
```