diff --git a/lib/bdev/bdev.c b/lib/bdev/bdev.c
index 37bc593bc..c8b28a2a9 100644
--- a/lib/bdev/bdev.c
+++ b/lib/bdev/bdev.c
@@ -3124,7 +3124,8 @@ spdk_bdev_open(struct spdk_bdev *bdev, bool write, spdk_bdev_remove_cb_t remove_
 	pthread_mutex_lock(&bdev->internal.mutex);
 
 	if (write && bdev->internal.claim_module) {
-		SPDK_ERRLOG("Could not open %s - already claimed\n", bdev->name);
+		SPDK_ERRLOG("Could not open %s - %s module already claimed it\n",
+			    bdev->name, bdev->internal.claim_module->name);
 		free(desc);
 		pthread_mutex_unlock(&bdev->internal.mutex);
 		return -EPERM;
diff --git a/lib/nvmf/subsystem.c b/lib/nvmf/subsystem.c
index 4ab8d7621..cf13f892c 100644
--- a/lib/nvmf/subsystem.c
+++ b/lib/nvmf/subsystem.c
@@ -898,6 +898,7 @@ _spdk_nvmf_subsystem_remove_ns(struct spdk_nvmf_subsystem *subsystem, uint32_t n
 
 	subsystem->ns[nsid - 1] = NULL;
 
+	spdk_bdev_module_release_bdev(ns->bdev);
 	spdk_bdev_close(ns->desc);
 	free(ns);
 
@@ -971,6 +972,11 @@ spdk_nvmf_ns_opts_get_defaults(struct spdk_nvmf_ns_opts *opts, size_t opts_size)
 	memset(opts, 0, opts_size);
 }
 
+/* Dummy bdev module used to to claim bdevs. */
+static struct spdk_bdev_module ns_bdev_module = {
+	.name	= "NVMe-oF Target",
+};
+
 uint32_t
 spdk_nvmf_subsystem_add_ns(struct spdk_nvmf_subsystem *subsystem, struct spdk_bdev *bdev,
 			   const struct spdk_nvmf_ns_opts *user_opts, size_t opts_size)
@@ -1060,6 +1066,12 @@ spdk_nvmf_subsystem_add_ns(struct spdk_nvmf_subsystem *subsystem, struct spdk_bd
 		free(ns);
 		return 0;
 	}
+	rc = spdk_bdev_module_claim_bdev(bdev, ns->desc, &ns_bdev_module);
+	if (rc != 0) {
+		spdk_bdev_close(ns->desc);
+		free(ns);
+		return 0;
+	}
 	subsystem->ns[opts.nsid - 1] = ns;
 
 	SPDK_DEBUGLOG(SPDK_LOG_NVMF, "Subsystem %s: bdev %s assigned nsid %" PRIu32 "\n",
diff --git a/test/nvmf/filesystem/filesystem.sh b/test/nvmf/filesystem/filesystem.sh
index f5c399034..f5158cd7e 100755
--- a/test/nvmf/filesystem/filesystem.sh
+++ b/test/nvmf/filesystem/filesystem.sh
@@ -32,8 +32,8 @@ for incapsule in 0 4096; do
 	$rpc_py set_nvmf_target_options -u 8192 -p 4 -c $incapsule
 	$rpc_py start_subsystem_init
 
-	bdevs="$bdevs $($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE)"
-	bdevs="$bdevs $($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE)"
+	bdevs="$($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE)"
+	bdevs+=" $($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE)"
 
 	modprobe -v nvme-rdma
 
diff --git a/test/nvmf/nvme_cli/nvme_cli.sh b/test/nvmf/nvme_cli/nvme_cli.sh
index 6c1e27772..2d05d1aa8 100755
--- a/test/nvmf/nvme_cli/nvme_cli.sh
+++ b/test/nvmf/nvme_cli/nvme_cli.sh
@@ -38,8 +38,8 @@ $rpc_py set_nvmf_target_options -u 8192 -p 4
 $rpc_py start_subsystem_init
 timing_exit start_nvmf_tgt
 
-bdevs="$bdevs $($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE)"
-bdevs="$bdevs $($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE)"
+bdevs="$($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE) "
+bdevs+="$($rpc_py construct_malloc_bdev $MALLOC_BDEV_SIZE $MALLOC_BLOCK_SIZE)"
 
 modprobe -v nvme-rdma
 
diff --git a/test/nvmf/rpc/rpc.sh b/test/nvmf/rpc/rpc.sh
index 5b3ab33d8..f4841a468 100755
--- a/test/nvmf/rpc/rpc.sh
+++ b/test/nvmf/rpc/rpc.sh
@@ -78,7 +78,6 @@ do
 	for bdev in $bdevs; do
 		let j=j+1
 		$rpc_py construct_nvmf_subsystem nqn.2016-06.io.spdk:cnode$j '' '' -s SPDK00000000000001
-		$rpc_py nvmf_subsystem_add_ns nqn.2016-06.io.spdk:cnode$j $bdev -n 10
 		$rpc_py nvmf_subsystem_add_ns nqn.2016-06.io.spdk:cnode$j $bdev -n 5
 		$rpc_py nvmf_subsystem_allow_any_host nqn.2016-06.io.spdk:cnode$j
 		nvme connect -t rdma -n nqn.2016-06.io.spdk:cnode$j -a "$NVMF_FIRST_TARGET_IP" -s "$NVMF_PORT"
@@ -93,7 +92,6 @@ do
 	j=0
 	for bdev in $bdevs; do
 		let j=j+1
-		$rpc_py nvmf_subsystem_remove_ns nqn.2016-06.io.spdk:cnode$j 10
 		$rpc_py nvmf_subsystem_remove_ns nqn.2016-06.io.spdk:cnode$j 5
 	done
 
diff --git a/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c b/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c
index 3eb829795..8d51c8ae0 100644
--- a/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c
+++ b/test/unit/lib/nvmf/ctrlr_discovery.c/ctrlr_discovery_ut.c
@@ -34,12 +34,21 @@
 #include "spdk/stdinc.h"
 
 #include "spdk_cunit.h"
+#include "spdk_internal/mock.h"
 
 #include "nvmf/ctrlr_discovery.c"
 #include "nvmf/subsystem.c"
 
 SPDK_LOG_REGISTER_COMPONENT("nvmf", SPDK_LOG_NVMF)
 
+DEFINE_STUB(spdk_bdev_module_claim_bdev,
+	    int,
+	    (struct spdk_bdev *bdev, struct spdk_bdev_desc *desc,
+	     struct spdk_bdev_module *module), 0);
+
+DEFINE_STUB_V(spdk_bdev_module_release_bdev,
+	      (struct spdk_bdev *bdev));
+
 uint32_t
 spdk_env_get_current_core(void)
 {
diff --git a/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c b/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
index c0a9778ec..6de943c30 100644
--- a/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
+++ b/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
@@ -34,11 +34,20 @@
 #include "spdk/stdinc.h"
 
 #include "spdk_cunit.h"
+#include "spdk_internal/mock.h"
 
 #include "nvmf/subsystem.c"
 
 SPDK_LOG_REGISTER_COMPONENT("nvmf", SPDK_LOG_NVMF)
 
+DEFINE_STUB(spdk_bdev_module_claim_bdev,
+	    int,
+	    (struct spdk_bdev *bdev, struct spdk_bdev_desc *desc,
+	     struct spdk_bdev_module *module), 0);
+
+DEFINE_STUB_V(spdk_bdev_module_release_bdev,
+	      (struct spdk_bdev *bdev));
+
 static void
 _subsystem_send_msg(spdk_thread_fn fn, void *ctx, void *thread_ctx)
 {