[PATCH v3 3/3] nvme-rdma: Handle number of queue changes

[Sagi Grimberg]

>>>> when iterating over all nr_hw_queues.
>>> I mean that we need realloc the ctrl->queues for
>>> nvme_rdma_start_io_queues(ctrl, 1, nr_queues).
>>> Otherwise, unallocated memory will be accessed when
>>> the new queue_count is bigger than the old one.
>>
>> That can't happen. ctrl->queues is allocated at the start
>> of the controller lifetime and will never exceed this queue
>> count.
> I don't understand why it can't happen.
> nvme_rdma_start_io_queues(ctrl, nr_queues, ctrl->tag_set.nr_hw_queues + 1)
> is designed for dealing with the scenario that the new queue_count is
> bigger than the old one. it will access the unallocated memory.
> ctrl->queues is just allocated the first queue count buffers at the start
> of the controller lifetime, if the new queue count is bigger than the
> first queue count, ctrl-queues will be insufficient.

queue_count cannot be larger than what the user asked for, and that is
the number of entries ctrl->queues is spanning.