All of lore.kernel.org
 help / color / mirror / Atom feed
From: Dean Jenkins <Dean_Jenkins@mentor.com>
To: Marcel Holtmann <marcel@holtmann.org>
Cc: Dean Jenkins <Dean_Jenkins@mentor.com>,
	"Gustavo F . Padovan" <gustavo@padovan.org>,
	Johan Hedberg <johan.hedberg@gmail.com>,
	<linux-bluetooth@vger.kernel.org>
Subject: [RFC V1 10/16] Bluetooth: hci_ldisc: hci_uart_tty_close() detach tty after last msg
Date: Tue, 28 Mar 2017 18:50:23 +0100	[thread overview]
Message-ID: <1490723429-28870-11-git-send-email-Dean_Jenkins@mentor.com> (raw)
In-Reply-To: <1490723429-28870-1-git-send-email-Dean_Jenkins@mentor.com>

hci_uart_tty_close() is detaching the tty prematurely which prevents
the Data Link protocol layer from using the tty serial port in the
call to hci_unregister_dev().

Consequently, when hci_unregister_dev() attempts to send a HCI RESET
command, the BCSP layer attempts to retransmit the message many times
and the command is timed-out after HCI_CMD_TIMEOUT (2) seconds.
Nothing was physically transmitted because the tty was detached too
early.

Therefore, move the detach statement "tty->disc_data = NULL" to after
hci_unregister_dev() so that the HCI RESET command maybe sent and
acknowledged.

Signed-off-by: Dean Jenkins <Dean_Jenkins@mentor.com>
---
 drivers/bluetooth/hci_ldisc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c
index 2d5c6f0..e7d1b8b 100644
--- a/drivers/bluetooth/hci_ldisc.c
+++ b/drivers/bluetooth/hci_ldisc.c
@@ -493,9 +493,6 @@ static void hci_uart_tty_close(struct tty_struct *tty)
 
 	BT_DBG("tty %p", tty);
 
-	/* Detach from the tty */
-	tty->disc_data = NULL;
-
 	if (!hu)
 		return;
 
@@ -517,6 +514,9 @@ static void hci_uart_tty_close(struct tty_struct *tty)
 		hu->proto->close(hu);
 	}
 
+	/* Detach from the tty */
+	tty->disc_data = NULL;
+
 	clear_bit(HCI_UART_PROTO_SET, &hu->flags);
 
 	if (test_and_clear_bit(HCI_UART_REGISTERED, &hu->flags)) {
-- 
2.7.4

  parent reply	other threads:[~2017-03-28 17:50 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-28 17:50 [RFC V1 00/16] hci_ldisc hci_uart_tty_close() fixes Dean Jenkins
2017-03-28 17:50 ` [RFC V1 01/16] Bluetooth: hci_ldisc: Add missing return in hci_uart_init_work() Dean Jenkins
2017-03-28 17:50 ` [RFC V1 02/16] Bluetooth: hci_ldisc: Ensure hu->hdev set to NULL before freeing hdev Dean Jenkins
2017-03-28 17:50 ` [RFC V1 03/16] Bluetooth: hci_ldisc: Add missing clear HCI_UART_PROTO_READY Dean Jenkins
2017-03-28 17:50 ` [RFC V1 04/16] Bluetooth: hci_ldisc: Add HCI RESET comment to hci_unregister_dev() call Dean Jenkins
2017-03-30 10:11   ` Marcel Holtmann
2017-03-28 17:50 ` [RFC V1 05/16] Bluetooth: hci_ldisc: Add protocol check to hci_uart_send_frame() Dean Jenkins
2017-03-28 17:50 ` [RFC V1 06/16] Bluetooth: hci_ldisc: Add protocol check to hci_uart_dequeue() Dean Jenkins
2017-03-28 17:50 ` [RFC V1 07/16] Bluetooth: hci_ldisc: Add protocol check to hci_uart_tx_wakeup() Dean Jenkins
2017-03-30 10:11   ` Marcel Holtmann
2017-03-28 17:50 ` [RFC V1 08/16] Bluetooth: hci_ldisc: Separate flag handling in hci_uart_tty_close() Dean Jenkins
2017-03-28 17:50 ` [RFC V1 09/16] Bluetooth: hci_ldisc: Tidy-up HCI_UART_REGISTERED " Dean Jenkins
2017-03-28 17:50 ` Dean Jenkins [this message]
2017-03-28 17:50 ` [RFC V1 11/16] Bluetooth: hci_ldisc: hci_uart_tty_close() move hci_uart_close() Dean Jenkins
2017-03-28 17:50 ` [RFC V1 12/16] Bluetooth: hci_ldisc: hci_uart_tty_close() move cancel_work_sync() Dean Jenkins
2017-03-28 17:50 ` [RFC V1 13/16] Bluetooth: hci_ldisc: hci_uart_tty_close() free hu->tx_skb Dean Jenkins
2017-03-28 17:50 ` [RFC V1 14/16] Bluetooth: hci_ldisc: Simplify flushing Dean Jenkins
2017-03-28 17:50 ` [RFC V1 15/16] Bluetooth: hci_ldisc: Use rwlocking to avoid closing proto races Dean Jenkins
2017-03-28 17:50 ` [RFC V1 16/16] Bluetooth: hci_ldisc: Add ioctl_mutex avoiding concurrency Dean Jenkins
2017-03-30 10:11 ` [RFC V1 00/16] hci_ldisc hci_uart_tty_close() fixes Marcel Holtmann
2017-04-03 15:09   ` Dean Jenkins
2017-04-03 15:51     ` Marcel Holtmann
2017-04-04 20:36       ` Dean Jenkins
2017-04-05 15:28         ` Dean Jenkins
2017-04-06  7:23           ` Marcel Holtmann

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1490723429-28870-11-git-send-email-Dean_Jenkins@mentor.com \
    --to=dean_jenkins@mentor.com \
    --cc=gustavo@padovan.org \
    --cc=johan.hedberg@gmail.com \
    --cc=linux-bluetooth@vger.kernel.org \
    --cc=marcel@holtmann.org \
    --subject='Re: [RFC V1 10/16] Bluetooth: hci_ldisc: hci_uart_tty_close() detach tty after last msg' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.