[openib-general] create QP failure

[Roland Dreier]

 >   In my case, where I was pretty much literally calling:
 >    ibv_create_qp(c->qp,&attr);
 >    check_for_errors();
 >    ibv_create_qp(c->qp_ack,&attr);
 >    check_for_errors();

 >    The second create_qp call failed over.
 >    So maybe the answer to your question about parameter passing can
 > be discovered from that ;)

 >    Apparently it is (now?) necessary to use a seperate - or 'reset'
 > the old one - ibv_qp_init_attr struct to pass to subsequent
 > ibv_create_qp() calls.

No, this is a bug in the verbs library or the kernel driver.  It
should work fine to reuse the same structure, and it should not be
necessary to clear anything in the attributes.  Can you give more
details about the failure you're seeing?  For example, could you dump
the QP attributes structure before and after the first ibv_create_qp()
call?  Or you could just post a test case that shows the problem.

 - R.