diff --git a/mm/percpu.c b/mm/percpu.c
index 014bab6..d39e2f4 100644
--- a/mm/percpu.c
+++ b/mm/percpu.c
@@ -1591,7 +1591,7 @@
 			if (cpu == NR_CPUS)
 				continue;
 
-			PCPU_SETUP_BUG_ON(cpu > nr_cpu_ids);
+			PCPU_SETUP_BUG_ON(cpu >= nr_cpu_ids);
 			PCPU_SETUP_BUG_ON(!cpu_possible(cpu));
 			PCPU_SETUP_BUG_ON(unit_map[cpu] != UINT_MAX);