diff --git a/lib/iscsi/portal_grp.c b/lib/iscsi/portal_grp.c
index 76c841938..e4f8aefdd 100644
--- a/lib/iscsi/portal_grp.c
+++ b/lib/iscsi/portal_grp.c
@@ -69,18 +69,13 @@ spdk_iscsi_portal_find_by_addr(const char *host, const char *port)
 struct spdk_iscsi_portal *
 spdk_iscsi_portal_create(const char *host, const char *port, const char *cpumask)
 {
-	struct spdk_iscsi_portal *p = NULL;
+	struct spdk_iscsi_portal *p = NULL, *tmp;
 	struct spdk_cpuset *core_mask = NULL;
 	int rc;
 
 	assert(host != NULL);
 	assert(port != NULL);
 
-	p = spdk_iscsi_portal_find_by_addr(host, port);
-	if (p != NULL) {
-		SPDK_ERRLOG("portal (%s, %s) already exists\n", host, port);
-		return NULL;
-	}
 
 	p = calloc(1, sizeof(*p));
 	if (!p) {
@@ -140,7 +135,16 @@ spdk_iscsi_portal_create(const char *host, const char *port, const char *cpumask
 	p->group = NULL; /* set at a later time by caller */
 	p->acceptor_poller = NULL;
 
+	pthread_mutex_lock(&g_spdk_iscsi.mutex);
+	tmp = spdk_iscsi_portal_find_by_addr(host, port);
+	if (tmp != NULL) {
+		pthread_mutex_unlock(&g_spdk_iscsi.mutex);
+		SPDK_ERRLOG("portal (%s, %s) already exists\n", host, port);
+		goto error_out;
+	}
+
 	TAILQ_INSERT_TAIL(&g_spdk_iscsi.portal_head, p, g_tailq);
+	pthread_mutex_unlock(&g_spdk_iscsi.mutex);
 
 	return p;
 
@@ -159,11 +163,16 @@ spdk_iscsi_portal_destroy(struct spdk_iscsi_portal *p)
 	assert(p != NULL);
 
 	SPDK_DEBUGLOG(SPDK_LOG_ISCSI, "spdk_iscsi_portal_destroy\n");
+
+	pthread_mutex_lock(&g_spdk_iscsi.mutex);
 	TAILQ_REMOVE(&g_spdk_iscsi.portal_head, p, g_tailq);
+	pthread_mutex_unlock(&g_spdk_iscsi.mutex);
+
 	free(p->host);
 	free(p->port);
 	spdk_cpuset_free(p->cpumask);
 	free(p);
+
 }
 
 static int
@@ -562,13 +571,16 @@ spdk_iscsi_portal_grp_array_create(void)
 void
 spdk_iscsi_portal_grp_array_destroy(void)
 {
-	struct spdk_iscsi_portal_grp *pg, *tmp;
+	struct spdk_iscsi_portal_grp *pg;
 
 	SPDK_DEBUGLOG(SPDK_LOG_ISCSI, "spdk_iscsi_portal_grp_array_destroy\n");
 	pthread_mutex_lock(&g_spdk_iscsi.mutex);
-	TAILQ_FOREACH_SAFE(pg, &g_spdk_iscsi.pg_head, tailq, tmp) {
+	while (!TAILQ_EMPTY(&g_spdk_iscsi.pg_head)) {
+		pg = TAILQ_FIRST(&g_spdk_iscsi.pg_head);
 		TAILQ_REMOVE(&g_spdk_iscsi.pg_head, pg, tailq);
+		pthread_mutex_unlock(&g_spdk_iscsi.mutex);
 		spdk_iscsi_portal_grp_destroy(pg);
+		pthread_mutex_lock(&g_spdk_iscsi.mutex);
 	}
 	pthread_mutex_unlock(&g_spdk_iscsi.mutex);
 }
@@ -653,7 +665,5 @@ spdk_iscsi_portal_grp_release(struct spdk_iscsi_portal_grp *pg)
 {
 	spdk_iscsi_portal_grp_close(pg);
 	spdk_iscsi_portal_grp_unregister(pg);
-	pthread_mutex_lock(&g_spdk_iscsi.mutex);
 	spdk_iscsi_portal_grp_destroy(pg);
-	pthread_mutex_unlock(&g_spdk_iscsi.mutex);
 }
diff --git a/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c b/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c
index 6006ca562..2a0454a9a 100644
--- a/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c
+++ b/test/unit/lib/iscsi/portal_grp.c/portal_grp_ut.c
@@ -45,6 +45,7 @@ static int
 test_setup(void)
 {
 	TAILQ_INIT(&g_spdk_iscsi.portal_head);
+	pthread_mutex_init(&g_spdk_iscsi.mutex, NULL);
 	return 0;
 }