diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 0df2448eb5d1c6dc825f3162725331cf8d377a2e..4055f2008cc6194bac431759d3820f36e7fba1f9 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -728,6 +728,12 @@ void cputime_adjust(struct task_cputime *curr, struct prev_cputime *prev,
 	}
 
 	stime = scale_stime(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:
 	/*