diff --git a/drivers/tty/serial/8250/8250_early.c b/drivers/tty/serial/8250/8250_early.c
index 946ddd2b3a541990277aabad488843a429e3e6f5..c100d6343d508cd9b690ca3eb7c0e59e2fe87ef3 100644
--- a/drivers/tty/serial/8250/8250_early.c
+++ b/drivers/tty/serial/8250/8250_early.c
@@ -194,7 +194,7 @@ static int __init parse_options(struct early_serial8250_device *device,
 		options++;
 		device->baud = simple_strtoul(options, NULL, 0);
 		length = min(strcspn(options, " ") + 1,
-			     sizeof(device->options));
+			     (size_t)(sizeof(device->options)));
 		strlcpy(device->options, options, length);
 	} else {
 		device->baud = probe_baud(port);