[ofa-general] Behavior on dropped message

[Dotan Barak]

Hi.

Tang, Changqing wrote:
> Hi,
> 	I have question on dropped message. During QP connection setup,
> QPs are in INIT state, after exchange the qp_num,
> one end is moving INIT-->RTR-->RTS, the other end is still in INIT
> state.
>
> 	Then the side in RTS state sends a message. From the standard,
> the message is silently dropped on the receiving
> side because it is still in INIT state. What is the behavior on the
> sending side ? Do I get compeletion error, or never
> get a completion ?
>
> 	On Mellanox HCA, I got completion error. But for the new
> connectX card, I never get a completion event, and my
> code is hanging there.
>   
The sending QP don't get any response from the remote QP (because it is 
in INIT state and its SQ is not enabled yet),
so the (retry) timeout of the sender will be expired for retry_cnt times 
and you should get retry exceeded completion.

You should get this behavior for all of the HCAs.
(unless you are using timeout = 0 which means infinite timeout)

Which FW are you using for the connectX?

thanks
Dotan