diff --git a/arch/mn10300/kernel/time.c b/arch/mn10300/kernel/time.c
index 8f7f6d22783d..0b5c856b4266 100644
--- a/arch/mn10300/kernel/time.c
+++ b/arch/mn10300/kernel/time.c
@@ -54,6 +54,9 @@ unsigned long long sched_clock(void)
 	unsigned long tsc, tmp;
 	unsigned product[3]; /* 96-bit intermediate value */
 
+	/* cnt32_to_63() is not safe with preemption */
+	preempt_disable();
+
 	/* read the TSC value
 	 */
 	tsc = 0 - get_cycles(); /* get_cycles() counts down */
@@ -64,6 +67,8 @@ unsigned long long sched_clock(void)
 	 */
 	tsc64.ll = cnt32_to_63(tsc) & 0x7fffffffffffffffULL;
 
+	preempt_enable();
+
 	/* scale the 64-bit TSC value to a nanosecond value via a 96-bit
 	 * intermediate
 	 */