diff --git a/include/spdk_internal/event.h b/include/spdk_internal/event.h
index a738ed3cf..e2fc9d24b 100644
--- a/include/spdk_internal/event.h
+++ b/include/spdk_internal/event.h
@@ -70,7 +70,7 @@ struct spdk_subsystem_depend {
 void spdk_add_subsystem(struct spdk_subsystem *subsystem);
 void spdk_add_subsystem_depend(struct spdk_subsystem_depend *depend);
 
-void spdk_subsystem_init(void *arg1, void *arg2);
+void spdk_subsystem_init(struct spdk_event *app_start_event);
 void spdk_subsystem_fini(void);
 void spdk_subsystem_init_next(int rc);
 void spdk_subsystem_config(FILE *fp);
diff --git a/lib/event/app.c b/lib/event/app.c
index 094f46149..b17e19581 100644
--- a/lib/event/app.c
+++ b/lib/event/app.c
@@ -379,8 +379,7 @@ spdk_app_start(struct spdk_app_opts *opts, spdk_event_fn start_fn,
 	app_start_event = spdk_event_allocate(spdk_env_get_current_core(), start_fn,
 					      arg1, arg2);
 
-	spdk_event_call(spdk_event_allocate(spdk_env_get_current_core(), spdk_subsystem_init,
-					    app_start_event, NULL));
+	spdk_subsystem_init(app_start_event);
 
 	/* This blocks until spdk_app_stop is called */
 	spdk_reactors_start();
diff --git a/lib/event/subsystem.c b/lib/event/subsystem.c
index 45505f26d..dd7cab86e 100644
--- a/lib/event/subsystem.c
+++ b/lib/event/subsystem.c
@@ -36,6 +36,7 @@
 #include "spdk/log.h"
 
 #include "spdk_internal/event.h"
+#include "spdk/env.h"
 
 static TAILQ_HEAD(spdk_subsystem_list, spdk_subsystem) g_subsystems =
 	TAILQ_HEAD_INITIALIZER(g_subsystems);
@@ -138,13 +139,11 @@ spdk_subsystem_init_next(int rc)
 	}
 }
 
-void
-spdk_subsystem_init(void *arg1, void *arg2)
+static void
+spdk_subsystem_verify(void *arg1, void *arg2)
 {
 	struct spdk_subsystem_depend *dep;
 
-	g_app_start_event = (struct spdk_event *)arg1;
-
 	/* Verify that all dependency name and depends_on subsystems are registered */
 	TAILQ_FOREACH(dep, &g_depends, tailq) {
 		if (!spdk_subsystem_find(&g_subsystems, dep->name)) {
@@ -165,6 +164,17 @@ spdk_subsystem_init(void *arg1, void *arg2)
 	spdk_subsystem_init_next(0);
 }
 
+void
+spdk_subsystem_init(struct spdk_event *app_start_event)
+{
+	struct spdk_event *verify_event;
+
+	g_app_start_event = app_start_event;
+
+	verify_event = spdk_event_allocate(spdk_env_get_current_core(), spdk_subsystem_verify, NULL, NULL);
+	spdk_event_call(verify_event);
+}
+
 void
 spdk_subsystem_fini(void)
 {
diff --git a/test/unit/lib/event/subsystem.c/subsystem_ut.c b/test/unit/lib/event/subsystem.c/subsystem_ut.c
index 427e3aae2..076613178 100644
--- a/test/unit/lib/event/subsystem.c/subsystem_ut.c
+++ b/test/unit/lib/event/subsystem.c/subsystem_ut.c
@@ -47,8 +47,33 @@ spdk_app_stop(int rc)
 	global_rc = rc;
 }
 
+uint32_t
+spdk_env_get_current_core(void)
+{
+	return 0;
+}
+
+static void
+ut_event_fn(void *arg1, void *arg2)
+{
+}
+
+struct spdk_event *
+spdk_event_allocate(uint32_t core, spdk_event_fn fn, void *arg1, void *arg2)
+{
+	struct spdk_event *event = calloc(1, sizeof(*event));
+
+	event->fn = fn;
+	event->arg1 = arg1;
+	event->arg2 = arg2;
+
+	return event;
+}
+
 void spdk_event_call(struct spdk_event *event)
 {
+	event->fn(event->arg1, event->arg2);
+	free(event);
 }
 
 static void
@@ -89,9 +114,11 @@ subsystem_sort_test_depends_on_single(void)
 	struct spdk_subsystem *subsystem;
 	int i;
 	char subsystem_name[16];
+	struct spdk_event *app_start_event;
 
 	global_rc = -1;
-	spdk_subsystem_init(NULL, NULL);
+	app_start_event = spdk_event_allocate(0, ut_event_fn, NULL, NULL);
+	spdk_subsystem_init(app_start_event);
 
 	i = 4;
 	TAILQ_FOREACH(subsystem, &g_subsystems, tailq) {
@@ -107,6 +134,7 @@ subsystem_sort_test_depends_on_multiple(void)
 {
 	int i;
 	struct spdk_subsystem *subsystem;
+	struct spdk_event *app_start_event;
 
 	subsystem_clear();
 	set_up_subsystem(&g_ut_subsystems[0], "iscsi");
@@ -136,7 +164,8 @@ subsystem_sort_test_depends_on_multiple(void)
 	}
 
 	global_rc = -1;
-	spdk_subsystem_init(NULL, NULL);
+	app_start_event = spdk_event_allocate(0, ut_event_fn, NULL, NULL);
+	spdk_subsystem_init(app_start_event);
 
 	subsystem = TAILQ_FIRST(&g_subsystems);
 	CU_ASSERT(strcmp(subsystem->name, "interface") == 0);
@@ -195,7 +224,7 @@ subsystem_sort_test_missing_dependency(void)
 	spdk_add_subsystem_depend(&g_ut_subsystem_deps[0]);
 
 	global_rc = -1;
-	spdk_subsystem_init(NULL, NULL);
+	spdk_subsystem_init(NULL);
 	CU_ASSERT(global_rc != 0);
 
 	/*
@@ -210,7 +239,7 @@ subsystem_sort_test_missing_dependency(void)
 	spdk_add_subsystem_depend(&g_ut_subsystem_deps[0]);
 
 	global_rc = -1;
-	spdk_subsystem_init(NULL, NULL);
+	spdk_subsystem_init(NULL);
 	CU_ASSERT(global_rc != 0);
 
 }