diff --git a/libcpuid/cpuid_main.c b/libcpuid/cpuid_main.c
index 6051885..0c228f8 100644
--- a/libcpuid/cpuid_main.c
+++ b/libcpuid/cpuid_main.c
@@ -177,6 +177,10 @@ static bool set_cpu_affinity(logical_cpu_t logical_cpu)
 {
 	thread_affinity_policy_data_t ap;
 	ap.affinity_tag = logical_cpu + 1;
+	/* Note: thread_policy_set() always returns KERN_SUCCESS even if the target logical CPU does not exist
+	   Refer to #178 */
+	if (logical_cpu >= get_total_cpus())
+		return false;
 	return thread_policy_set(mach_thread_self(), THREAD_AFFINITY_POLICY, (thread_policy_t) &ap, THREAD_AFFINITY_POLICY_COUNT) == KERN_SUCCESS;
 }
 #define SET_CPU_AFFINITY