I am having issues getting my convertor/driver combination to work correctly with io-net. 

My driver will be working with IP packets directly so there is no need for my convertor to do anything other than just 
immediately pass the IP packets given to it to the driver and to the IP stack. 

I have setup my driver to have up-type foo, and my convertor to uptype IP and bot_type foo.

When sending IP packets (an ICMP echo request in my given test) from one of my devices to another here's what happens:

Requesting device
1) My convertor gets the request and passes it down to the driver
2) The driver receives the request and sends it to the other device

Receiving device
1) My driver receives the echo request and calls tx_up_start
2) My convertor receives the echo request and calls tx_up_start
3) TxDone is called in my driver (not by my convertor so I am assuming this is done by the ip stack) - is there any way 
I can see some log info on what io-net and the ip stack are doing with this?
4) I never receive an rxdown in my convertor for the echo response that I should see.

I have verified the contents of the npkt_t data portion and it matches the original IP packet that is sent to my 
convertor on the originating device. I have verified that the route table is configured correctly as well.

Does anyone have any pointers on what could be wrong here? I have to assume I am not setting something up right, but my 
code is completly based on the pppmgr and online documentation examples.