1 files changed, 10 insertions, 5 deletions

diff --git a/drivers/tty/tty_ldisc.c b/drivers/tty/tty_ldisc.c
index 0f2a2c5e704c..f4e6754525dc 100644
--- a/drivers/tty/tty_ldisc.c
+++ b/drivers/tty/tty_ldisc.c
@@ -512,7 +512,7 @@ static void tty_ldisc_restore(struct tty_struct *tty, struct tty_ldisc *old)
 static int tty_ldisc_halt(struct tty_struct *tty)
 {
         clear_bit(TTY_LDISC, &tty->flags);
-        return cancel_work_sync(&tty->buf.work);
+        return cancel_work_sync(&tty->port->buf.work);
 }
 
 /**
@@ -525,7 +525,7 @@ static void tty_ldisc_flush_works(struct tty_struct *tty)
 {
         flush_work(&tty->hangup_work);
         flush_work(&tty->SAK_work);
-        flush_work(&tty->buf.work);
+        flush_work(&tty->port->buf.work);
 }
 
 /**
@@ -704,9 +704,9 @@ enable:
         /* Restart the work queue in case no characters kick it off. Safe if
            already running */
         if (work)
-                schedule_work(&tty->buf.work);
+                schedule_work(&tty->port->buf.work);
         if (o_work)
-                schedule_work(&o_tty->buf.work);
+                schedule_work(&o_tty->port->buf.work);
         mutex_unlock(&tty->ldisc_mutex);
         tty_unlock(tty);
         return retval;
@@ -817,7 +817,7 @@ void tty_ldisc_hangup(struct tty_struct *tty)
          */
         clear_bit(TTY_LDISC, &tty->flags);
         tty_unlock(tty);
-        cancel_work_sync(&tty->buf.work);
+        cancel_work_sync(&tty->port->buf.work);
         mutex_unlock(&tty->ldisc_mutex);
 retry:
         tty_lock(tty);
@@ -897,6 +897,11 @@ int tty_ldisc_setup(struct tty_struct *tty, struct tty_struct *o_tty)
 
 static void tty_ldisc_kill(struct tty_struct *tty)
 {
+        /* There cannot be users from userspace now. But there still might be
+         * drivers holding a reference via tty_ldisc_ref. Do not steal them the
+         * ldisc until they are done. */
+        tty_ldisc_wait_idle(tty, MAX_SCHEDULE_TIMEOUT);
+
         mutex_lock(&tty->ldisc_mutex);
         /*
          * Now kill off the ldisc