diff --git a/kernel/ksysfs.c b/kernel/ksysfs.c
index 5b9276b..3feaf5a 100644
--- a/kernel/ksysfs.c
+++ b/kernel/ksysfs.c
@@ -103,7 +103,7 @@ KERNEL_ATTR_RO(kexec_crash_loaded);
 static ssize_t kexec_crash_size_show(struct kobject *kobj,
 				       struct kobj_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%lu\n", crash_get_memory_size());
+	return sprintf(buf, "%zu\n", crash_get_memory_size());
 }
 static ssize_t kexec_crash_size_store(struct kobject *kobj,
 				   struct kobj_attribute *attr,