diff -dru vmxnet3-only.orig/vmxnet3.c vmxnet3-only/vmxnet3.c
--- vmxnet3-only.orig/vmxnet3.c	2012-02-15 16:07:44.000000000 +0100
+++ vmxnet3-only/vmxnet3.c	2012-05-20 11:20:47.280333352 +0200
@@ -1146,7 +1146,6 @@
    /* If this device is being reset, dont reset it again. */
    if (test_and_set_bit(&sc->state, VMXNET3_STATE_BIT_RESETTING)) {
       VMXNET3_LOG(sc->dev, 1, "Device being reset, watchdog will exit");
-      ifp->if_timer = 1;
       VMXNET3_UNLOCK(sc);
       return;
    }
@@ -1200,7 +1199,6 @@
 vmxnet3_close_locked(vmxnet3_adapter_t *sc)
 {
    int i;
-   sc->ifp->if_watchdog = NULL;
 
    if (!(sc->ifp->if_drv_flags & IFF_DRV_RUNNING)) {
       VMXNET3_LOG(sc->dev, 1, "Interface already closed.\n");
@@ -1269,10 +1267,6 @@
       return ret;
    }
 
-   /* Setup watchdog function */
-   sc->ifp->if_watchdog = NULL;//vmxnet3_watchdog;
-   sc->ifp->if_timer = 1;
-
    VMXNET3_LOG(sc->dev, 1, "Interface activated.\n");
    return 0;
 }
@@ -2090,7 +2084,6 @@
    ifp              = sc->ifp;
    if_initname(ifp, device_get_name(dev), device_get_unit(dev));
    ifp->if_softc    = sc;
-   ifp->if_timer    = 1;
    ifp->if_flags    = IFF_BROADCAST | IFF_MULTICAST | IFF_SIMPLEX;
 
    ifp->if_capabilities = IFCAP_HWCSUM | IFCAP_VLAN_HWTAGGING | IFCAP_VLAN_MTU |
diff -dru vmxnet3-only.orig/vmxnet3_int.h vmxnet3-only/vmxnet3_int.h
--- vmxnet3-only.orig/vmxnet3_int.h	2012-02-15 16:07:44.000000000 +0100
+++ vmxnet3-only/vmxnet3_int.h	2012-05-20 11:21:32.132987316 +0200
@@ -134,9 +134,6 @@
 #define VMXNET3_GET_ADDR_LO(dma)   ((uint32_t)(dma))
 #define VMXNET3_GET_ADDR_HI(dma)   ((uint32_t)(((uint64_t)(dma)) >> 32))
 
-inline Bool set_bit(uint8_t *field, uint8_t bit);
-inline Bool test_and_set_bit(uint8_t *field, uint8_t bit);
-
 /* Following are not neccesarily atomic operations */
 static inline Bool
 set_bit(uint8_t *field, uint8_t bit) {
diff -dru vmxnet3-only.orig/vmxnet3_tx.c vmxnet3-only/vmxnet3_tx.c
--- vmxnet3-only.orig/vmxnet3_tx.c	2012-02-15 16:07:44.000000000 +0100
+++ vmxnet3-only/vmxnet3_tx.c	2012-05-20 11:29:24.144945489 +0200
@@ -470,6 +470,12 @@
 
    sop = (Vmxnet3_TxDesc *)(tq->cmd_ring.base + tq->cmd_ring.next2fill);
 
+   if (m_head == NULL) {
+      VMXNET3_LOG(sc->dev, 1, "Warning : Called with no mbuf (m_head == NULL) !\n");
+      tq->stats.drop_total++;
+      return EINVAL;
+   } 
+
    for (m = m_head; m != NULL; m = m->m_next) {
       tbi = tq->cmd_ring.buf_info + tq->cmd_ring.next2fill;
       txd = (Vmxnet3_TxDesc *)tq->cmd_ring.base + tq->cmd_ring.next2fill;