[openib-general] umad abi 2 v 3 and multicast join failed

[Roland Dreier]

    Troy> warn: [24878] umad_init: wrong ABI version:
    Troy> /sys/class/infiniband_mad/abi_version is 2 but library ABI
    Troy> is 3

    Hal> Right. This is old OpenSM (actually old libibumad) with the
    Hal> latest from OpenIB svn (past where I put the changes to
    Hal> support send side RMPP in).

Are you sure?  The kernel seems to be reporting an older ABI version
than the library is looking for.

In general, given that kernels 2.6.11 and 2.6.12 are shipping with ABI
version 2, does it make sense to avoid problems like this by keeping
the old userspace code around and having the library decide at runtime
which ABI to use?

 - R.