[openib-general] IPoIB Loading and Starting

[Roland Dreier]

    Michael> The SM only knows what it configures in each port.  The
    Michael> SA is responsible for service management and it works
    Michael> with the SM to map a given service to a P_Key.

As far as I know there is no service (in the IB service record sense)
associated to IPoIB, is there?

    Michael> IPoverIB is required to inquire what groups are available
    Michael> and optionally set up event notification to be informed
    Michael> when groups are added for its particular service.  This
    Michael> eliminates the need for local P_Key management.

I don't see this requirement anywhere in the current IETF drafts,
although I could be missing it.  In any case this seems rather ugly,
since the only way to get a list of IPoIB multicast groups seems to be
to query for _all_ multicast groups, filter for those that match the
IPoIB GID format, and then attempt to join to find out which can be
used on each local port.

    Michael> In general, the IPoverIB driver should treat each new
    Michael> all-nodes multicast group with a unique P_Key as a
    Michael> virtual hot-plug event (this was our intent both within
    Michael> the IETF and in the IBTA).

Hmm.. this view does not seem to match the wording of the current
IPoIB drafts.  For example:

        It is an implementation choice on how the P_Key and the scope
        bits related to the IPoIB subnet are determined by the
        implementation. These could be configuration parameters
        initialized by some means by the administrator.

        The methods employed by an implementation to determine the
        P_Key and scope bits are not specified by IPoIB.

Thanks,
  Roland