working carrier function and removing the module does not crash the server anymore

network_device/flxnet_dev.c

@@ -218,6 +218,11 @@ struct flxnet_peer *find_peer_for_netdev(struct net_device *dev) {
 void flxnet_remove_peer(struct flxnet_peer *peer) {
 	int rv;
 	set_carrier(peer, false);
+	netif_stop_queue(peer->flxnet);
+	netif_carrier_off(peer->flxnet);
+	unregister_netdev(peer->flxnet);
+	free_netdev(peer->flxnet);
+	kfree(peer->tx_queue.packets);
 
 	if (message_level & NETIF_MSG_LINK)
 		pr_info("flxnet_dev: removing peer %p from the network\n", peer);
@@ -1146,6 +1151,8 @@ void __exit flxnet_dev_exit(void) {
 	if (!list_empty(&peers)) {
 		mutex_lock(&peer_mutex);
 		list_for_each_entry_safe(peer, tmp, &peers, list_head) {
+			netif_stop_queue(peer->flxnet);
+			netif_carrier_off(peer->flxnet);
 			unregister_netdev(peer->flxnet);
 			free_netdev(peer->flxnet);
 			kfree(peer->tx_queue.packets);