A departing reader must restart a flush_to_ldisc() worker _before_ the next reader enters the read loop; this is to avoid the new reader concluding no more i/o is available and prematurely exiting, when the old reader simply hasn't re-started the worker yet. Cc: stable@xxxxxxxxxx # 3.12 Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx> --- drivers/tty/n_tty.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/tty/n_tty.c b/drivers/tty/n_tty.c index 7a744b6..ce11cd5 100644 --- a/drivers/tty/n_tty.c +++ b/drivers/tty/n_tty.c @@ -2250,6 +2250,9 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file, if (time) timeout = time; } + n_tty_set_room(tty); + up_read(&tty->termios_rwsem); + mutex_unlock(&ldata->atomic_read_lock); remove_wait_queue(&tty->read_wait, &wait); @@ -2260,8 +2263,6 @@ static ssize_t n_tty_read(struct tty_struct *tty, struct file *file, if (b - buf) retval = b - buf; - n_tty_set_room(tty); - up_read(&tty->termios_rwsem); return retval; } -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
