[PATCH 04/10] tty: tty_buffer: warn if losing flags in __tty_insert_flip_string_flags()

["Jiri Slaby (SUSE)" <jirislaby@xxxxxxxxxx>]

And add a WARN_ON_ONCE(need_flags) to make sure we are not losing flags
in __tty_insert_flip_string_flags().

Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx>
---
 drivers/tty/tty_buffer.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c
index 94a88dc05a54..c101b4ab737e 100644
--- a/drivers/tty/tty_buffer.c
+++ b/drivers/tty/tty_buffer.c
@@ -325,6 +325,9 @@ int __tty_insert_flip_string_flags(struct tty_port *port, const u8 *chars,
 			flags += space;
 		} else if (tb->flags) {
 			memset(flag_buf_ptr(tb, tb->used), flags[0], space);
+		} else {
+			/* tb->flags should be available once requested */
+			WARN_ON_ONCE(need_flags);
 		}
 
 		tb->used += space;
-- 
2.41.0