I see ( http://www.mellanox.com/page/osv_support_ib ) that Infiniband MLNX_OFED 2.0 is supported on XenServer 6.1.0.
Will MLNX_OFED 2.0 be supported on 6.2.0 ?
No due date yet but it's on the road map.
Can I use Infiniband in Dom0 (host) with remote disk storage (eg. iSCSI/iSER or SRP) ?
Yes
Can I use Infiniband in Dom0 (host) for networking (eg. IPoIB) ?
Yes
Can I use Infiniband in Dom0 (host) for live migration (XenMotion) of DomU (eg. accelerate IP over Infiniband for example with Infiniband SDP) ?
This sounds like it should be feasible from a stack point of view, however I am not aware of a current working implementation.
Can be Infiniband card (eg. QP and CQ) virtualized to DomU (guest) (see http://xen.xensource.com/files/summit_3/xs0106_virtualizing_infiniband.pdf and http://www.mellanox.com/pdf/presentations/xs0106_infiniband.pdf ) any progress from 2006?
I don't believe we have a product/solution that would be similar to this other than SR-IOV which going forward I believe will be the preferred implementation used for this effect.
Is SR-IOV for DomU (guest) supported (with MLNX_OFED 2.0) in XenServer for all ConnectX cards?
I am not sure it will be all ConnectX cards. ConnectX is EOL but I am confident it supports ConnectX2 and ConnectX3 generations.