diff --git a/app/nvmf_tgt/conf.c b/app/nvmf_tgt/conf.c
index 9201568a0..8556c6c6a 100644
--- a/app/nvmf_tgt/conf.c
+++ b/app/nvmf_tgt/conf.c
@@ -125,7 +125,6 @@ spdk_add_nvmf_discovery_subsystem(void)
 	}
 
 	spdk_nvmf_subsystem_set_allow_any_host(app_subsys->subsystem, true);
-	nvmf_tgt_start_subsystem(app_subsys);
 
 	return 0;
 }
@@ -499,8 +498,6 @@ spdk_nvmf_construct_subsystem(const char *name, int32_t lcore,
 
 	}
 
-	nvmf_tgt_start_subsystem(app_subsys);
-
 	return 0;
 
 error:
diff --git a/app/nvmf_tgt/nvmf_tgt.c b/app/nvmf_tgt/nvmf_tgt.c
index 14bc8f76c..e28a7e479 100644
--- a/app/nvmf_tgt/nvmf_tgt.c
+++ b/app/nvmf_tgt/nvmf_tgt.c
@@ -55,48 +55,17 @@ static size_t g_active_poll_groups = 0;
 static struct spdk_poller *g_acceptor_poller = NULL;
 
 static TAILQ_HEAD(, nvmf_tgt_subsystem) g_subsystems = TAILQ_HEAD_INITIALIZER(g_subsystems);
-static bool g_subsystems_shutdown;
 
 static void nvmf_tgt_advance_state(void *arg1, void *arg2);
 
-static void
-subsystem_delete_event(void *arg1, void *arg2)
-{
-	struct nvmf_tgt_subsystem *app_subsys = arg1;
-	struct spdk_nvmf_subsystem *subsystem = app_subsys->subsystem;
-
-	TAILQ_REMOVE(&g_subsystems, app_subsys, tailq);
-	free(app_subsys);
-
-	spdk_nvmf_delete_subsystem(subsystem);
-
-	if (g_subsystems_shutdown && TAILQ_EMPTY(&g_subsystems)) {
-		g_tgt.state = NVMF_TGT_FINI_FREE_RESOURCES;
-		nvmf_tgt_advance_state(NULL, NULL);
-	}
-}
-
-static void
-subsystem_stop(void *arg1, void *arg2)
-{
-	struct nvmf_tgt_subsystem *app_subsys = arg1;
-	struct spdk_event *event = arg2;
-
-	spdk_nvmf_subsystem_stop(app_subsys->subsystem);
-
-	spdk_event_call(event);
-}
-
 static void
 nvmf_tgt_delete_subsystem(struct nvmf_tgt_subsystem *app_subsys)
 {
-	struct spdk_event *event1, *event2;
+	TAILQ_REMOVE(&g_subsystems, app_subsys, tailq);
 
-	event2 = spdk_event_allocate(spdk_env_get_current_core(), subsystem_delete_event,
-				     app_subsys, NULL);
-	event1 = spdk_event_allocate(app_subsys->lcore, subsystem_stop, app_subsys, event2);
+	spdk_nvmf_delete_subsystem(app_subsys->subsystem);
 
-	spdk_event_call(event1);
+	free(app_subsys);
 }
 
 static void
@@ -110,25 +79,6 @@ spdk_nvmf_shutdown_cb(void)
 	nvmf_tgt_advance_state(NULL, NULL);
 }
 
-static void
-_nvmf_tgt_start_subsystem(void *arg1, void *arg2)
-{
-	struct nvmf_tgt_subsystem *app_subsys = arg1;
-	struct spdk_nvmf_subsystem *subsystem = app_subsys->subsystem;
-
-	spdk_nvmf_subsystem_start(subsystem);
-}
-
-void
-nvmf_tgt_start_subsystem(struct nvmf_tgt_subsystem *app_subsys)
-{
-	struct spdk_event *event;
-
-	event = spdk_event_allocate(app_subsys->lcore, _nvmf_tgt_start_subsystem,
-				    app_subsys, NULL);
-	spdk_event_call(event);
-}
-
 struct nvmf_tgt_subsystem *
 nvmf_tgt_create_subsystem(const char *name, enum spdk_nvmf_subtype subtype, uint32_t num_ns,
 			  uint32_t lcore)
@@ -314,10 +264,10 @@ nvmf_tgt_advance_state(void *arg1, void *arg2)
 		case NVMF_TGT_FINI_SHUTDOWN_SUBSYSTEMS: {
 			struct nvmf_tgt_subsystem *app_subsys, *tmp;
 
-			g_subsystems_shutdown = true;
 			TAILQ_FOREACH_SAFE(app_subsys, &g_subsystems, tailq, tmp) {
 				nvmf_tgt_delete_subsystem(app_subsys);
 			}
+			g_tgt.state = NVMF_TGT_FINI_FREE_RESOURCES;
 			break;
 		}
 		case NVMF_TGT_FINI_FREE_RESOURCES:
diff --git a/app/nvmf_tgt/nvmf_tgt.h b/app/nvmf_tgt/nvmf_tgt.h
index 8c9081097..84563bce0 100644
--- a/app/nvmf_tgt/nvmf_tgt.h
+++ b/app/nvmf_tgt/nvmf_tgt.h
@@ -91,8 +91,6 @@ nvmf_tgt_subsystem_next(struct nvmf_tgt_subsystem *subsystem);
 
 int spdk_nvmf_parse_conf(void);
 
-void nvmf_tgt_start_subsystem(struct nvmf_tgt_subsystem *subsystem);
-
 struct nvmf_tgt_subsystem *nvmf_tgt_create_subsystem(const char *name,
 		enum spdk_nvmf_subtype subtype, uint32_t num_ns,
 		uint32_t lcore);
diff --git a/include/spdk/nvmf.h b/include/spdk/nvmf.h
index ecf4611e9..13273fc97 100644
--- a/include/spdk/nvmf.h
+++ b/include/spdk/nvmf.h
@@ -139,15 +139,6 @@ struct spdk_nvmf_subsystem *spdk_nvmf_create_subsystem(struct spdk_nvmf_tgt *tgt
 struct spdk_nvmf_subsystem *spdk_nvmf_tgt_find_subsystem(struct spdk_nvmf_tgt *tgt,
 		const char *subnqn);
 
-/**
- * Initialize the subsystem on the thread that will be used to poll it.
- *
- * \param subsystem Subsystem that will be polled on this core.
- */
-int spdk_nvmf_subsystem_start(struct spdk_nvmf_subsystem *subsystem);
-
-void spdk_nvmf_subsystem_stop(struct spdk_nvmf_subsystem *subsystem);
-
 void spdk_nvmf_delete_subsystem(struct spdk_nvmf_subsystem *subsystem);
 
 /**
diff --git a/lib/nvmf/ctrlr_bdev.c b/lib/nvmf/ctrlr_bdev.c
index b2ac7cf59..b9532f5ef 100644
--- a/lib/nvmf/ctrlr_bdev.c
+++ b/lib/nvmf/ctrlr_bdev.c
@@ -380,6 +380,7 @@ spdk_nvmf_ctrlr_process_io_cmd(struct spdk_nvmf_request *req)
 	struct spdk_bdev *bdev;
 	struct spdk_bdev_desc *desc;
 	struct spdk_io_channel *ch;
+	struct spdk_nvmf_poll_group *group = req->qpair->group;
 	struct spdk_nvmf_subsystem *subsystem = req->qpair->ctrlr->subsys;
 	struct spdk_nvme_cmd *cmd = &req->cmd->nvme_cmd;
 	struct spdk_nvme_cpl *response = &req->rsp->nvme_cpl;
@@ -397,7 +398,7 @@ spdk_nvmf_ctrlr_process_io_cmd(struct spdk_nvmf_request *req)
 
 	bdev = ns->bdev;
 	desc = ns->desc;
-	ch = ns->ch;
+	ch = group->sgroups[subsystem->id].channels[nsid - 1];
 	switch (cmd->opc) {
 	case SPDK_NVME_OPC_READ:
 		return nvmf_bdev_ctrlr_read_cmd(bdev, desc, ch, req);
@@ -413,64 +414,3 @@ spdk_nvmf_ctrlr_process_io_cmd(struct spdk_nvmf_request *req)
 		return nvmf_bdev_ctrlr_nvme_passthru_io(bdev, desc, ch, req);
 	}
 }
-
-static int
-spdk_nvmf_ns_bdev_attach(struct spdk_nvmf_ns *ns)
-{
-	if (ns->bdev == NULL) {
-		return 0;
-	}
-
-	ns->ch = spdk_bdev_get_io_channel(ns->desc);
-	if (ns->ch == NULL) {
-		SPDK_ERRLOG("io_channel allocation failed\n");
-		return -1;
-	}
-
-	return 0;
-}
-
-static void
-spdk_nvmf_ns_bdev_detach(struct spdk_nvmf_ns *ns)
-{
-	if (ns->bdev == NULL) {
-		return;
-	}
-
-	if (ns->ch) {
-		spdk_put_io_channel(ns->ch);
-		ns->ch = NULL;
-	}
-	if (ns->desc) {
-		spdk_bdev_close(ns->desc);
-		ns->desc = NULL;
-	}
-	ns->bdev = NULL;
-}
-
-int
-spdk_nvmf_subsystem_bdev_attach(struct spdk_nvmf_subsystem *subsystem)
-{
-	struct spdk_nvmf_ns *ns;
-
-	for (ns = spdk_nvmf_subsystem_get_first_ns(subsystem); ns != NULL;
-	     ns = spdk_nvmf_subsystem_get_next_ns(subsystem, ns)) {
-		if (spdk_nvmf_ns_bdev_attach(ns)) {
-			return -1;
-		}
-	}
-
-	return 0;
-}
-
-void
-spdk_nvmf_subsystem_bdev_detach(struct spdk_nvmf_subsystem *subsystem)
-{
-	struct spdk_nvmf_ns *ns;
-
-	for (ns = spdk_nvmf_subsystem_get_first_ns(subsystem); ns != NULL;
-	     ns = spdk_nvmf_subsystem_get_next_ns(subsystem, ns)) {
-		spdk_nvmf_ns_bdev_detach(ns);
-	}
-	subsystem->max_nsid = 0;
-}
diff --git a/lib/nvmf/nvmf_internal.h b/lib/nvmf/nvmf_internal.h
index 8abdcc5c5..ea8dbc84b 100644
--- a/lib/nvmf/nvmf_internal.h
+++ b/lib/nvmf/nvmf_internal.h
@@ -127,7 +127,6 @@ struct spdk_nvmf_request {
 struct spdk_nvmf_ns {
 	struct spdk_bdev *bdev;
 	struct spdk_bdev_desc *desc;
-	struct spdk_io_channel *ch;
 	uint32_t id;
 	bool allocated;
 };
@@ -240,8 +239,6 @@ bool spdk_nvmf_ctrlr_write_zeroes_supported(struct spdk_nvmf_ctrlr *ctrlr);
 
 int spdk_nvmf_bdev_ctrlr_identify_ns(struct spdk_bdev *bdev, struct spdk_nvme_ns_data *nsdata);
 
-int spdk_nvmf_subsystem_bdev_attach(struct spdk_nvmf_subsystem *subsystem);
-void spdk_nvmf_subsystem_bdev_detach(struct spdk_nvmf_subsystem *subsystem);
 int spdk_nvmf_subsystem_add_ctrlr(struct spdk_nvmf_subsystem *subsystem,
 				  struct spdk_nvmf_ctrlr *ctrlr);
 void spdk_nvmf_subsystem_remove_ctrlr(struct spdk_nvmf_subsystem *subsystem,
diff --git a/lib/nvmf/subsystem.c b/lib/nvmf/subsystem.c
index 588b29aa7..219271371 100644
--- a/lib/nvmf/subsystem.c
+++ b/lib/nvmf/subsystem.c
@@ -44,18 +44,6 @@
 #include "spdk_internal/bdev.h"
 #include "spdk_internal/log.h"
 
-int
-spdk_nvmf_subsystem_start(struct spdk_nvmf_subsystem *subsystem)
-{
-	return spdk_nvmf_subsystem_bdev_attach(subsystem);
-}
-
-void
-spdk_nvmf_subsystem_stop(struct spdk_nvmf_subsystem *subsystem)
-{
-	spdk_nvmf_subsystem_bdev_detach(subsystem);
-}
-
 static bool
 spdk_nvmf_valid_nqn(const char *nqn)
 {
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 a785f5104..aede115c5 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
@@ -144,17 +144,6 @@ spdk_nvmf_poll_group_add_ns(struct spdk_nvmf_poll_group *group,
 	return 0;
 }
 
-int
-spdk_nvmf_subsystem_bdev_attach(struct spdk_nvmf_subsystem *subsystem)
-{
-	return -1;
-}
-
-void
-spdk_nvmf_subsystem_bdev_detach(struct spdk_nvmf_subsystem *subsystem)
-{
-}
-
 static bool
 all_zero(const void *buf, size_t size)
 {
diff --git a/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c b/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
index 6a4e9e48b..1dbadd4bf 100644
--- a/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
+++ b/test/unit/lib/nvmf/subsystem.c/subsystem_ut.c
@@ -39,17 +39,6 @@
 
 SPDK_LOG_REGISTER_TRACE_FLAG("nvmf", SPDK_TRACE_NVMF)
 
-int
-spdk_nvmf_subsystem_bdev_attach(struct spdk_nvmf_subsystem *subsystem)
-{
-	return -1;
-}
-
-void
-spdk_nvmf_subsystem_bdev_detach(struct spdk_nvmf_subsystem *subsystem)
-{
-}
-
 int
 spdk_nvmf_transport_listen(struct spdk_nvmf_transport *transport,
 			   const struct spdk_nvme_transport_id *trid)