[openib-general] rtr & post_recv

[yipee]

Hi,

When connecting two reliable-connection qp's should I post receive buffers 
(using ibv_post_recv()) before modifying the qp's state to rtr (with 
ibv_modify_qp()) ? Or should I first modify the qp and then post the buffers?

I've stumbled across a problem that on some HCAs I must first do ibv_modify_qp() 
and then do ibv_post_recv() (a) or otherwise the connection never passes data 
sent with ibv_post_send() (b).

a. working
ibv_modify_qp(qp, rtr)
ibv_post_recv(qp, wr)

b. non-working (on some hcas)
ibv_post_recv(qp, wr)
ibv_modify_qp(qp, rtr)


Is this sequence defined anywhere? Or have I found a bug?


thanks,
y