rds: Lost locking in loop connection freeing

The conn is removed from list in there and this requires
proper lock protection.

Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/rds/loop.c

@@ -134,8 +134,12 @@ static int rds_loop_conn_alloc(struct rds_connection *conn, gfp_t gfp)
 static void rds_loop_conn_free(void *arg)
 {
 	struct rds_loop_connection *lc = arg;
+	unsigned long flags;
+
 	rdsdebug("lc %p\n", lc);
+	spin_lock_irqsave(&loop_conns_lock, flags);
 	list_del(&lc->loop_node);
+	spin_unlock_irqrestore(&loop_conns_lock, flags);
 	kfree(lc);
 }