diff --git a/master/ethernet.c b/master/ethernet.c
index 02aed613..4d5d1dda 100644
--- a/master/ethernet.c
+++ b/master/ethernet.c
@@ -31,6 +31,8 @@
 #include <linux/version.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
+#include <linux/lockdep.h>
+#include <linux/skbuff.h>
 
 #include "globals.h"
 #include "master.h"
@@ -826,6 +828,9 @@ int ec_eoedev_tx(struct sk_buff *skb, /**< transmit socket buffer */
     }
 #endif
 
+    WARN_ON_ONCE(skb_get_queue_mapping(skb) != 0);
+    lockdep_assert_held(&netdev_get_tx_queue(dev, 0)->_xmit_lock);
+
     if (!(frame =
           (ec_eoe_frame_t *) kmalloc(sizeof(ec_eoe_frame_t), GFP_ATOMIC))) {
         if (printk_ratelimit())