diff --git a/lib/event/reactor.c b/lib/event/reactor.c
index dd367fdae..1dc025a11 100644
--- a/lib/event/reactor.c
+++ b/lib/event/reactor.c
@@ -429,6 +429,11 @@ spdk_reactor_set_interrupt_mode(uint32_t lcore, bool new_in_interrupt,
 		return -EINVAL;
 	}
 
+	/* Eventfd has to be supported in order to use interrupt functionality. */
+	if (target->fgrp == NULL) {
+		return -ENOTSUP;
+	}
+
 	if (spdk_get_thread() != _spdk_get_app_thread()) {
 		SPDK_ERRLOG("It is only permitted within spdk application thread.\n");
 		return -EPERM;
diff --git a/test/unit/lib/event/reactor.c/reactor_ut.c b/test/unit/lib/event/reactor.c/reactor_ut.c
index 8f4baf0e5..5447ab37a 100644
--- a/test/unit/lib/event/reactor.c/reactor_ut.c
+++ b/test/unit/lib/event/reactor.c/reactor_ut.c
@@ -883,7 +883,9 @@ test_governor(void)
 	MOCK_SET(spdk_env_get_current_core, 0);
 	_reactors_scheduler_gather_metrics(NULL, NULL);
 
-	CU_ASSERT(_run_events_till_completion(2) == 6);
+	i = _run_events_till_completion(2);
+	/* Six runs when interrupt mode is supported, two if not. */
+	CU_ASSERT(i == 6 || i == 2);
 	MOCK_SET(spdk_env_get_current_core, 0);
 
 	/* Main core should be busy more than 50% time now - frequency should be raised */
@@ -906,7 +908,9 @@ test_governor(void)
 	MOCK_SET(spdk_env_get_current_core, 0);
 	_reactors_scheduler_gather_metrics(NULL, NULL);
 
-	CU_ASSERT(_run_events_till_completion(2) == 6);
+	i = _run_events_till_completion(2);
+	/* Six runs when interrupt mode is supported, two if not. */
+	CU_ASSERT(i == 6 || i == 2);
 	MOCK_SET(spdk_env_get_current_core, 0);
 
 	for (i = 0; i < 2; i++) {