ndo_start_xmit what to return when packet is too big!?

Hi everybody,

I was looking at network chapter of LDD3. The .ndo_start_xmit member
of struct net_device_ops should return netdev_tx_t which are:
enum netdev_tx {
        __NETDEV_TX_MIN  = INT_MIN,     /* make sure enum is signed */
        NETDEV_TX_OK     = 0x00,        /* driver took care of packet */
        NETDEV_TX_BUSY   = 0x10,        /* driver tx path was busy*/
        NETDEV_TX_LOCKED = 0x20,        /* driver tx lock was already taken */
};


I'm deling with some awkward hardware where the MTU is only 32 bytes
and was wondering. What should that function return in case of "too
large packet"?!?!?

Best regards,

-- 
"Do or do not. There is no try"
  Yoda Master