tty: Make core responsible for synchronizing its work
The tty core relies on the ldisc layer for synchronizing destruction
of the tty. Instead, the final tty release must wait for any pending tty
work to complete prior to tty destruction.
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
index 4587634..95e9712 100644
--- a/drivers/tty/tty_io.c
+++ b/drivers/tty/tty_io.c
@@ -1510,6 +1510,17 @@
}
EXPORT_SYMBOL(tty_free_termios);
+/**
+ * tty_flush_works - flush all works of a tty
+ * @tty: tty device to flush works for
+ *
+ * Sync flush all works belonging to @tty.
+ */
+static void tty_flush_works(struct tty_struct *tty)
+{
+ flush_work(&tty->SAK_work);
+ flush_work(&tty->hangup_work);
+}
/**
* release_one_tty - release tty structure memory
@@ -1831,6 +1842,12 @@
* Ask the line discipline code to release its structures
*/
tty_ldisc_release(tty, o_tty);
+
+ /* Wait for pending work before tty destruction commmences */
+ tty_flush_works(tty);
+ if (o_tty)
+ tty_flush_works(o_tty);
+
/*
* The release_tty function takes care of the details of clearing
* the slots and preserving the termios structure. The tty_unlock_pair