blktests failures with v6.4

[Sagi Grimberg]

> #3: nvme/003 (fabrics transport)
> 
>     When nvme test group is run with trtype=rdma or tcp, the test case fails
>     due to lockdep WARNING "possible circular locking dependency detected".
>     Reported in May/2023. Bart suggested a fix for trytpe=rdma [4] but it
>     needs more discussion.
> 
>     [4] https://lore.kernel.org/linux-nvme/20230511150321.103172-1-bvanassche@acm.org/

This patch is unfortunately incorrect and buggy.

This will likely make the issue go away, but adds another
old issue where a client can DDOS a target by bombarding it
with connect/disconnect. When releases are async and we don't
have any back-pressure, it is likely to happen.
--
diff --git a/drivers/nvme/target/rdma.c b/drivers/nvme/target/rdma.c
index 4597bca43a6d..8b4f4aa48206 100644
--- a/drivers/nvme/target/rdma.c
+++ b/drivers/nvme/target/rdma.c
@@ -1582,11 +1582,6 @@ static int nvmet_rdma_queue_connect(struct 
rdma_cm_id *cm_id,
                 goto put_device;
         }

-       if (queue->host_qid == 0) {
-               /* Let inflight controller teardown complete */
-               flush_workqueue(nvmet_wq);
-       }
-
         ret = nvmet_rdma_cm_accept(cm_id, queue, &event->param.conn);
         if (ret) {
                 /*
diff --git a/drivers/nvme/target/tcp.c b/drivers/nvme/target/tcp.c
index 868aa4de2e4c..c8cfa19e11c7 100644
--- a/drivers/nvme/target/tcp.c
+++ b/drivers/nvme/target/tcp.c
@@ -1844,11 +1844,6 @@ static u16 nvmet_tcp_install_queue(struct 
nvmet_sq *sq)
         struct nvmet_tcp_queue *queue =
                 container_of(sq, struct nvmet_tcp_queue, nvme_sq);

-       if (sq->qid == 0) {
-               /* Let inflight controller teardown complete */
-               flush_workqueue(nvmet_wq);
-       }
-
         queue->nr_cmds = sq->size * 2;
         if (nvmet_tcp_alloc_cmds(queue))
                 return NVME_SC_INTERNAL;
--