From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Hurley Subject: [PATCH] n_tty: Ensure reader restarts worker for next reader Date: Thu, 7 Nov 2013 13:59:46 -0500 Message-ID: <1383850796-24300-1-git-send-email-peter@hurleysoftware.com> References: <20131017211236.GA6155@kroah.com> Return-path: Received: from mailout02.c08.mtsvc.net ([205.186.168.190]:43898 "EHLO mailout02.c08.mtsvc.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751123Ab3KGTWY (ORCPT ); Thu, 7 Nov 2013 14:22:24 -0500 In-Reply-To: <20131017211236.GA6155@kroah.com> Sender: linux-serial-owner@vger.kernel.org List-Id: linux-serial@vger.kernel.org To: Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, Linus Torvalds , Mikael Pettersson , Andrew Morton , linux-serial@vger.kernel.org, Peter Hurley , stable@kernel.org 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@kernel.org # 3.12 Signed-off-by: Peter Hurley --- 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