diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index af7952f12e6cf19ac9b953fbbf54df823372f497..b453f8a6a7c76473ae8bdfb1b4ee668b3d110244 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -595,6 +595,12 @@ void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
 	}
 
 	stime = mul_u64_u64_div_u64(stime, rtime, stime + utime);
+	/*
+	 * Because mul_u64_u64_div_u64() can approximate on some
+	 * achitectures; enforce the constraint that: a*b/(b+c) <= a.
+	 */
+	if (unlikely(stime > rtime))
+		stime = rtime;
 
 update:
 	/*