nvmet_rdma crash - DISCONNECT event with NULL queue

[Sagi Grimberg]

>> I'll also try and reproduce this on mlx4 to rule out
>> iwarp and cxgb4 anomolies.
>
> Running the same test over mlx4/roce, I hit a warning in list_debug, and then a
> stuck CPU...

Steve,

Does this patch help?
--
diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index bafd9898b5f6..5946dac9564f 100644
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -951,6 +951,7 @@ static int nvmet_rdma_create_queue_ib(struct 
nvmet_rdma_queue *queue)

  static void nvmet_rdma_destroy_queue_ib(struct nvmet_rdma_queue *queue)
  {
+       ib_drain_qp(queue->cm_id->qp);
         rdma_destroy_qp(queue->cm_id);
         ib_free_cq(queue->cq);
  }
@@ -1247,7 +1248,6 @@ static void __nvmet_rdma_queue_disconnect(struct 
nvmet_rdma_queue *queue)

         if (disconnect) {
                 rdma_disconnect(queue->cm_id);
-               ib_drain_qp(queue->cm_id->qp);
                 schedule_work(&queue->release_work);
         }
  }
--