Netdev Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Kai-Heng Feng <kai.heng.feng@canonical.com>
To: marcel@holtmann.org, johan.hedberg@gmail.com, luiz.dentz@gmail.com
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>,
	Mattijs Korpershoek <mkorpershoek@baylibre.com>,
	Hsin-Yi Wang <hsinyi@chromium.org>,
	Guenter Roeck <linux@roeck-us.net>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>,
	linux-bluetooth@vger.kernel.org (open list:BLUETOOTH SUBSYSTEM),
	netdev@vger.kernel.org (open list:NETWORKING [GENERAL]),
	linux-kernel@vger.kernel.org (open list)
Subject: [PATCH v2] Bluetooth: Move shutdown callback before flushing tx and rx queue
Date: Tue, 10 Aug 2021 12:53:15 +0800	[thread overview]
Message-ID: <20210810045315.184383-1-kai.heng.feng@canonical.com> (raw)

Commit 0ea9fd001a14 ("Bluetooth: Shutdown controller after workqueues
are flushed or cancelled") introduced a regression that makes mtkbtsdio
driver stops working:
[   36.593956] Bluetooth: hci0: Firmware already downloaded
[   46.814613] Bluetooth: hci0: Execution of wmt command timed out
[   46.814619] Bluetooth: hci0: Failed to send wmt func ctrl (-110)

The shutdown callback depends on the result of hdev->rx_work, so we
should call it before flushing rx_work:
-> btmtksdio_shutdown()
 -> mtk_hci_wmt_sync()
  -> __hci_cmd_send()
   -> wait for BTMTKSDIO_TX_WAIT_VND_EVT gets cleared

-> btmtksdio_recv_event()
 -> hci_recv_frame()
  -> queue_work(hdev->workqueue, &hdev->rx_work)
   -> clears BTMTKSDIO_TX_WAIT_VND_EVT

So move the shutdown callback before flushing TX/RX queue to resolve the
issue.

Reported-and-tested-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Tested-by: Hsin-Yi Wang <hsinyi@chromium.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Fixes: 0ea9fd001a14 ("Bluetooth: Shutdown controller after workqueues are flushed or cancelled")
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
v2: 
 Move the shutdown callback before clearing HCI_UP, otherwise 1)
 shutdown callback won't be called and 2) other routines that depend on
 HCI_UP won't work.

 net/bluetooth/hci_core.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index cb2e9e513907..8622da2d9395 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -1727,6 +1727,14 @@ int hci_dev_do_close(struct hci_dev *hdev)
 	hci_request_cancel_all(hdev);
 	hci_req_sync_lock(hdev);
 
+	if (!hci_dev_test_flag(hdev, HCI_UNREGISTER) &&
+	    !hci_dev_test_flag(hdev, HCI_USER_CHANNEL) &&
+	    test_bit(HCI_UP, &hdev->flags)) {
+		/* Execute vendor specific shutdown routine */
+		if (hdev->shutdown)
+			hdev->shutdown(hdev);
+	}
+
 	if (!test_and_clear_bit(HCI_UP, &hdev->flags)) {
 		cancel_delayed_work_sync(&hdev->cmd_timer);
 		hci_req_sync_unlock(hdev);
@@ -1798,14 +1806,6 @@ int hci_dev_do_close(struct hci_dev *hdev)
 		clear_bit(HCI_INIT, &hdev->flags);
 	}
 
-	if (!hci_dev_test_flag(hdev, HCI_UNREGISTER) &&
-	    !hci_dev_test_flag(hdev, HCI_USER_CHANNEL) &&
-	    test_bit(HCI_UP, &hdev->flags)) {
-		/* Execute vendor specific shutdown routine */
-		if (hdev->shutdown)
-			hdev->shutdown(hdev);
-	}
-
 	/* flush cmd  work */
 	flush_work(&hdev->cmd_work);
 
-- 
2.31.1


             reply	other threads:[~2021-08-10  4:54 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-08-10  4:53 Kai-Heng Feng [this message]
2021-08-11  8:25 ` Mattijs Korpershoek
2021-08-16 15:49 ` 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=20210810045315.184383-1-kai.heng.feng@canonical.com \
    --to=kai.heng.feng@canonical.com \
    --cc=davem@davemloft.net \
    --cc=hsinyi@chromium.org \
    --cc=johan.hedberg@gmail.com \
    --cc=kuba@kernel.org \
    --cc=linux-bluetooth@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux@roeck-us.net \
    --cc=luiz.dentz@gmail.com \
    --cc=marcel@holtmann.org \
    --cc=mkorpershoek@baylibre.com \
    --cc=netdev@vger.kernel.org \
    --subject='Re: [PATCH v2] Bluetooth: Move shutdown callback before flushing tx and rx queue' \
    /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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).