net/mlx5: E-switch, register event handler before arming the event

Currently, mlx5 is registering event handler for vport context change
event some time after arming the event. this can lead to missing an
event, which will result in wrong rules in the FDB.
Hence, register the event handler before arming the event.

This solution is valid since FW is sending vport context change event
only on vports which SW armed, and SW arming the vport when enabling
it, which is done after the FDB has been created.

Fixes: 6933a937 ("net/mlx5: E-Switch, Use async events chain")
Signed-off-by: Shay Drory <shayd@nvidia.com>
Reviewed-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

drivers/net/ethernet/mellanox/mlx5/core/eswitch.c

@@ -1038,11 +1038,8 @@ const u32 *mlx5_esw_query_functions(struct mlx5_core_dev *dev)
 	return ERR_PTR(err);
 }
 
-static void mlx5_eswitch_event_handlers_register(struct mlx5_eswitch *esw)
+static void mlx5_eswitch_event_handler_register(struct mlx5_eswitch *esw)
 {
-	MLX5_NB_INIT(&esw->nb, eswitch_vport_event, NIC_VPORT_CHANGE);
-	mlx5_eq_notifier_register(esw->dev, &esw->nb);
-
 	if (esw->mode == MLX5_ESWITCH_OFFLOADS && mlx5_eswitch_is_funcs_handler(esw->dev)) {
 		MLX5_NB_INIT(&esw->esw_funcs.nb, mlx5_esw_funcs_changed_handler,
 			     ESW_FUNCTIONS_CHANGED);
@@ -1050,13 +1047,11 @@ static void mlx5_eswitch_event_handlers_register(struct mlx5_eswitch *esw)
 	}
 }
 
-static void mlx5_eswitch_event_handlers_unregister(struct mlx5_eswitch *esw)
+static void mlx5_eswitch_event_handler_unregister(struct mlx5_eswitch *esw)
 {
 	if (esw->mode == MLX5_ESWITCH_OFFLOADS && mlx5_eswitch_is_funcs_handler(esw->dev))
 		mlx5_eq_notifier_unregister(esw->dev, &esw->esw_funcs.nb);
 
-	mlx5_eq_notifier_unregister(esw->dev, &esw->nb);
-
 	flush_workqueue(esw->work_queue);
 }
 
@@ -1483,6 +1478,9 @@ int mlx5_eswitch_enable_locked(struct mlx5_eswitch *esw, int num_vfs)
 
 	mlx5_eswitch_update_num_of_vfs(esw, num_vfs);
 
+	MLX5_NB_INIT(&esw->nb, eswitch_vport_event, NIC_VPORT_CHANGE);
+	mlx5_eq_notifier_register(esw->dev, &esw->nb);
+
 	if (esw->mode == MLX5_ESWITCH_LEGACY) {
 		err = esw_legacy_enable(esw);
 	} else {
@@ -1495,7 +1493,7 @@ int mlx5_eswitch_enable_locked(struct mlx5_eswitch *esw, int num_vfs)
 
 	esw->fdb_table.flags |= MLX5_ESW_FDB_CREATED;
 
-	mlx5_eswitch_event_handlers_register(esw);
+	mlx5_eswitch_event_handler_register(esw);
 
 	esw_info(esw->dev, "Enable: mode(%s), nvfs(%d), necvfs(%d), active vports(%d)\n",
 		 esw->mode == MLX5_ESWITCH_LEGACY ? "LEGACY" : "OFFLOADS",
@@ -1622,7 +1620,8 @@ void mlx5_eswitch_disable_locked(struct mlx5_eswitch *esw)
 	 */
 	mlx5_esw_mode_change_notify(esw, MLX5_ESWITCH_LEGACY);
 
-	mlx5_eswitch_event_handlers_unregister(esw);
+	mlx5_eq_notifier_unregister(esw->dev, &esw->nb);
+	mlx5_eswitch_event_handler_unregister(esw);
 
 	esw_info(esw->dev, "Disable: mode(%s), nvfs(%d), necvfs(%d), active vports(%d)\n",
 		 esw->mode == MLX5_ESWITCH_LEGACY ? "LEGACY" : "OFFLOADS",