diff --git a/drivers/char/tty_buffer.c b/drivers/char/tty_buffer.c
index f27c4d6d..73b60a19 100644
--- a/drivers/char/tty_buffer.c
+++ b/drivers/char/tty_buffer.c
@@ -247,7 +247,7 @@ int tty_insert_flip_string(struct tty_struct *tty, const unsigned char *chars,
 {
 	int copied = 0;
 	do {
-		int goal = min(size - copied, TTY_BUFFER_PAGE);
+		int goal = min((size_t)(size - copied), (size_t)TTY_BUFFER_PAGE);
 		int space = tty_buffer_request_room(tty, goal);
 		struct tty_buffer *tb = tty->buf.tail;
 		/* If there is no space then tb may be NULL */
@@ -284,7 +284,7 @@ int tty_insert_flip_string_flags(struct tty_struct *tty,
 {
 	int copied = 0;
 	do {
-		int goal = min(size - copied, TTY_BUFFER_PAGE);
+		int goal = min((size_t)(size - copied), (size_t)TTY_BUFFER_PAGE);
 		int space = tty_buffer_request_room(tty, goal);
 		struct tty_buffer *tb = tty->buf.tail;
 		/* If there is no space then tb may be NULL */