diff --git a/drivers/base/cpu.c b/drivers/base/cpu.c
index a55b590..d8c7f3e 100644
--- a/drivers/base/cpu.c
+++ b/drivers/base/cpu.c
@@ -139,7 +139,7 @@
 {
 	ssize_t rc;
 
-	rc = sprintf(buf, "%lu\n", sizeof(note_buf_t));
+	rc = sprintf(buf, "%zu\n", sizeof(note_buf_t));
 	return rc;
 }
 static DEVICE_ATTR(crash_notes_size, 0400, show_crash_notes_size, NULL);