nvme-fabrics: crash at nvme connect-all

[Sagi Grimberg]

> Hello Sagi,
> Unfortunately it crashes still (this time at the first connect already).
> I'm investigating this.

OK, looking further into your bug report its actually different from
the one I got. I do think that this patch makes sense regardless.

 From your log I can only guess that you are using iWARP devices?
because I see that nvmet tries to init an MR pool and seem to
run out of memory...

Which device are you using? Are you running on a low memory machine?
Perhaps the rdma rw code needs to check max_mr capability?

Also, are you running the host and target on a single server? it might
be possible that it requires more resources than the host (or device)
has?