[PATCH net-next 7/7] net: dsa: replay a deletion of switchdev objects for ports leaving a bridged LAG

[Vladimir Oltean <olteanv@gmail.com>]

From: Vladimir Oltean <vladimir.oltean@nxp.com>

When a DSA switch port leaves a bonding interface that is under a
bridge, there might be dangling switchdev objects on that port left
behind, because the bridge is not aware that its lower interface (the
bond) changed state in any way.

Call the bridge replay helpers with adding=false before changing
dp->bridge_dev to NULL, because we need to simulate to
dsa_slave_port_obj_del() that these notifications were emitted by the
bridge.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 net/dsa/port.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/net/dsa/port.c b/net/dsa/port.c
index 4e58d07ececd..787c0454f9bd 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -212,7 +212,22 @@ static int dsa_port_switchdev_sync(struct dsa_port *dp,
 	return 0;
 }
 
-static void dsa_port_switchdev_unsync(struct dsa_port *dp)
+static void dsa_port_switchdev_unsync_objs(struct dsa_port *dp)
+{
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+	struct net_device *br = dp->bridge_dev;
+
+	/* Delete the switchdev objects left on this port */
+	br_mdb_replay(br, brport_dev, dp, false,
+		      &dsa_slave_switchdev_blocking_notifier, NULL);
+
+	br_fdb_replay(br, brport_dev, dp, false, &dsa_slave_switchdev_notifier);
+
+	br_vlan_replay(br, brport_dev, dp, false,
+		       &dsa_slave_switchdev_blocking_notifier, NULL);
+}
+
+static void dsa_port_switchdev_unsync_attrs(struct dsa_port *dp)
 {
 	/* Configure the port for standalone mode (no address learning,
 	 * flood everything).
@@ -288,6 +303,8 @@ void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
 	};
 	int err;
 
+	dsa_port_switchdev_unsync_objs(dp);
+
 	/* Here the port is already unbridged. Reflect the current configuration
 	 * so that drivers can program their chips accordingly.
 	 */
@@ -297,7 +314,7 @@ void dsa_port_bridge_leave(struct dsa_port *dp, struct net_device *br)
 	if (err)
 		pr_err("DSA: failed to notify DSA_NOTIFIER_BRIDGE_LEAVE\n");
 
-	dsa_port_switchdev_unsync(dp);
+	dsa_port_switchdev_unsync_attrs(dp);
 }
 
 int dsa_port_lag_change(struct dsa_port *dp,
-- 
2.25.1