From feacbecb39db098cd9f6d728dcb00d753a3f36ed Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Fri, 7 Sep 2018 15:19:06 +0200 Subject: TTY: tty_buffer, warn on leaks When we leak some tty buffer, warn about that. For that we need to account the memory used also in the tty_buffer_free_all function. On other locations, the accounting is handled correctly. Note that we do not account the free list, as that was accounted in tty_buffer_free before put on the free list. I have been using this patch for ages, so let's see if anybody else encounters any issues. Signed-off-by: Jiri Slaby Signed-off-by: Greg Kroah-Hartman --- drivers/tty/tty_buffer.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers/tty') diff --git a/drivers/tty/tty_buffer.c b/drivers/tty/tty_buffer.c index c996b6859c5e..76151c002858 100644 --- a/drivers/tty/tty_buffer.c +++ b/drivers/tty/tty_buffer.c @@ -118,9 +118,12 @@ void tty_buffer_free_all(struct tty_port *port) struct tty_bufhead *buf = &port->buf; struct tty_buffer *p, *next; struct llist_node *llist; + unsigned int freed = 0; + int still_used; while ((p = buf->head) != NULL) { buf->head = p->next; + freed += p->size; if (p->size > 0) kfree(p); } @@ -132,7 +135,9 @@ void tty_buffer_free_all(struct tty_port *port) buf->head = &buf->sentinel; buf->tail = &buf->sentinel; - atomic_set(&buf->mem_used, 0); + still_used = atomic_xchg(&buf->mem_used, 0); + WARN(still_used != freed, "we still have not freed %d bytes!", + still_used - freed); } /** -- cgit v1.2.3