nvmet_rdma crash - DISCONNECT event with NULL queue

[Sagi Grimberg]

> This looks good.  But you mentioned the 2 rapid-fire keep alive timeout logs for
> the same controller as being seriously broken. Perhaps that is another problem?
> Maybe keep alives aren't getting stopped correctly or something...
>
> But:  I'll try this patch and run for a few hours and see what happens.  I
> believe regardless of a keep alive issue, the above patch is still needed.

In your tests, can you enable dynamic debug on:
nvmet_start_keep_alive_timer
nvmet_stop_keep_alive_timer
nvmet_execute_keep_alive

Thanks,