[ofa-general] Re: IPoIB CM connectivity issue.

[Roland Dreier]

 > In case if connection initiated by remote node(B), OFED node(A)
 > accepts connection and then sends it's own connect request to the same
 > node(B) using different RC QP!

Yes, in the Linux implementation of IPoIB CM, each QP is used for
traffic in only a single direction.  This simplifies things quite a bit
in the implementation, and as far as I know is a fully compliant thing
to do.

 > It looks like violation of RFC4755 convention to send unicast data over
 > connected QP.

I assume you mean sending ARP replies.  Yes, you are correct.  I never
noticed before but RFC 4755 does say:

   Additionally, all address resolution responses (ARP or Neighbor
   Discovery) MUST always be encapsulated in a UD mode packet.

So we should fix the Linux implementation to respect this.  However I'm
somewhat surprised that this is an issue, given that unicast_arp_send()
seems like it never would issue a CM send.

 - R.