diff --git a/kernel/reboot.c b/kernel/reboot.c
index e7b78d5ae1ab..8fbba433725e 100644
--- a/kernel/reboot.c
+++ b/kernel/reboot.c
@@ -551,22 +551,15 @@ static int __init reboot_setup(char *str)
 			break;
 
 		case 's':
-		{
-			int rc;
-
-			if (isdigit(*(str+1))) {
-				rc = kstrtoint(str+1, 0, &reboot_cpu);
-				if (rc)
-					return rc;
-			} else if (str[1] == 'm' && str[2] == 'p' &&
-				   isdigit(*(str+3))) {
-				rc = kstrtoint(str+3, 0, &reboot_cpu);
-				if (rc)
-					return rc;
-			} else
+			if (isdigit(*(str+1)))
+				reboot_cpu = simple_strtoul(str+1, NULL, 0);
+			else if (str[1] == 'm' && str[2] == 'p' &&
+							isdigit(*(str+3)))
+				reboot_cpu = simple_strtoul(str+3, NULL, 0);
+			else
 				*mode = REBOOT_SOFT;
 			break;
-		}
+
 		case 'g':
 			*mode = REBOOT_GPIO;
 			break;