Re: [PATCH v2 2/2] Bluetooth: Fix printing errors if LE Connection times out

[Ahmad Fatoum <a.fatoum@pengutronix.de>]

Hello Luiz,

On 27.03.23 22:53, Luiz Augusto von Dentz wrote:
> From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> 
> This fixes errors like bellow when LE Connection times out since that
> is actually not a controller error:
> 
>  Bluetooth: hci0: Opcode 0x200d failed: -110
>  Bluetooth: hci0: request failed to create LE connection: err -110
> 
> Instead the code shall properly detect if -ETIMEDOUT is returned and
> send HCI_OP_LE_CREATE_CONN_CANCEL to give up on the connection.
> 
> Link: https://github.com/bluez/bluez/issues/340

I assume the issue described in the Github PR to be the same issue
I had reported here:

https://lore.kernel.org/linux-bluetooth/a1ce1743-e450-6cdb-dfab-56a3e3eb9aed@pengutronix.de/

I gave these patches a test and all pairing attempts after the first pair/unpair
are still unsuccessful. Only visible change to me is that there's no -110 error
message printed anymore with default log level.

Cheers,
Ahmad

#regzbot monitor: https://lore.kernel.org/linux-bluetooth/a1ce1743-e450-6cdb-dfab-56a3e3eb9aed@pengutronix.de/

> Fixes: Fixes: 8e8b92ee60de ("Bluetooth: hci_sync: Add hci_le_create_conn_sync")
> Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
> ---
>  include/net/bluetooth/hci_core.h |  1 +
>  net/bluetooth/hci_conn.c         |  7 +++++--
>  net/bluetooth/hci_event.c        | 16 ++++++----------
>  net/bluetooth/hci_sync.c         | 13 ++++++++++---
>  4 files changed, 22 insertions(+), 15 deletions(-)
> 
> diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
> index 53d3328c2b8b..e22e45fbe8db 100644
> --- a/include/net/bluetooth/hci_core.h
> +++ b/include/net/bluetooth/hci_core.h
> @@ -954,6 +954,7 @@ enum {
>  	HCI_CONN_STK_ENCRYPT,
>  	HCI_CONN_AUTH_INITIATOR,
>  	HCI_CONN_DROP,
> +	HCI_CONN_CANCEL,
>  	HCI_CONN_PARAM_REMOVAL_PEND,
>  	HCI_CONN_NEW_LINK_KEY,
>  	HCI_CONN_SCANNING,
> diff --git a/net/bluetooth/hci_conn.c b/net/bluetooth/hci_conn.c
> index 5af3f6b011c9..e4aee5950c36 100644
> --- a/net/bluetooth/hci_conn.c
> +++ b/net/bluetooth/hci_conn.c
> @@ -1233,6 +1233,8 @@ static void create_le_conn_complete(struct hci_dev *hdev, void *data, int err)
>  {
>  	struct hci_conn *conn = data;
>  
> +	bt_dev_dbg(hdev, "err %d", err);
> +
>  	hci_dev_lock(hdev);
>  
>  	if (!err) {
> @@ -1240,8 +1242,6 @@ static void create_le_conn_complete(struct hci_dev *hdev, void *data, int err)
>  		goto done;
>  	}
>  
> -	bt_dev_err(hdev, "request failed to create LE connection: err %d", err);
> -
>  	/* Check if connection is still pending */
>  	if (conn != hci_lookup_le_connect(hdev))
>  		goto done;
> @@ -2771,6 +2771,9 @@ int hci_abort_conn(struct hci_conn *conn, u8 reason)
>  {
>  	int r = 0;
>  
> +	if (test_and_set_bit(HCI_CONN_CANCEL, &conn->flags))
> +		return 0;
> +
>  	switch (conn->state) {
>  	case BT_CONNECTED:
>  	case BT_CONFIG:
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index 8d8547fa9032..ff99e8c2750f 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -2886,16 +2886,6 @@ static void cs_le_create_conn(struct hci_dev *hdev, bdaddr_t *peer_addr,
>  
>  	conn->resp_addr_type = peer_addr_type;
>  	bacpy(&conn->resp_addr, peer_addr);
> -
> -	/* We don't want the connection attempt to stick around
> -	 * indefinitely since LE doesn't have a page timeout concept
> -	 * like BR/EDR. Set a timer for any connection that doesn't use
> -	 * the accept list for connecting.
> -	 */
> -	if (filter_policy == HCI_LE_USE_PEER_ADDR)
> -		queue_delayed_work(conn->hdev->workqueue,
> -				   &conn->le_conn_timeout,
> -				   conn->conn_timeout);
>  }
>  
>  static void hci_cs_le_create_conn(struct hci_dev *hdev, u8 status)
> @@ -5907,6 +5897,12 @@ static void le_conn_complete_evt(struct hci_dev *hdev, u8 status,
>  	if (status)
>  		goto unlock;
>  
> +	/* Drop the connection if it has been aborted */
> +	if (test_bit(HCI_CONN_CANCEL, &conn->flags)) {
> +		hci_conn_drop(conn);
> +		goto unlock;
> +	}
> +
>  	if (conn->dst_type == ADDR_LE_DEV_PUBLIC)
>  		addr_type = BDADDR_LE_PUBLIC;
>  	else
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 4376b6f06702..31231f0e4a28 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -246,8 +246,9 @@ int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
>  
>  	skb = __hci_cmd_sync_sk(hdev, opcode, plen, param, event, timeout, sk);
>  	if (IS_ERR(skb)) {
> -		bt_dev_err(hdev, "Opcode 0x%4x failed: %ld", opcode,
> -				PTR_ERR(skb));
> +		if (!event)
> +			bt_dev_err(hdev, "Opcode 0x%4x failed: %ld", opcode,
> +				   PTR_ERR(skb));
>  		return PTR_ERR(skb);
>  	}
>  
> @@ -5128,8 +5129,11 @@ static int hci_le_connect_cancel_sync(struct hci_dev *hdev,
>  	if (test_bit(HCI_CONN_SCANNING, &conn->flags))
>  		return 0;
>  
> +	if (test_and_set_bit(HCI_CONN_CANCEL, &conn->flags))
> +		return 0;
> +
>  	return __hci_cmd_sync_status(hdev, HCI_OP_LE_CREATE_CONN_CANCEL,
> -				     6, &conn->dst, HCI_CMD_TIMEOUT);
> +				     0, NULL, HCI_CMD_TIMEOUT);
>  }
>  
>  static int hci_connect_cancel_sync(struct hci_dev *hdev, struct hci_conn *conn)
> @@ -6103,6 +6107,9 @@ int hci_le_create_conn_sync(struct hci_dev *hdev, struct hci_conn *conn)
>  				       conn->conn_timeout, NULL);
>  
>  done:
> +	if (err == -ETIMEDOUT)
> +		hci_le_connect_cancel_sync(hdev, conn);
> +
>  	/* Re-enable advertising after the connection attempt is finished. */
>  	hci_resume_advertising_sync(hdev);
>  	return err;

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