Received-SPF: pass (google.com: domain of linux-bluetooth-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20220725135026.1.Ia18502557c4ba9ba7cd2d1da2bae3aeb71b37e4e@changeid>
In-Reply-To: <20220725135026.1.Ia18502557c4ba9ba7cd2d1da2bae3aeb71b37e4e@changeid>
From:   Luiz Augusto von Dentz <luiz.dentz@gmail.com>
Date:   Mon, 25 Jul 2022 15:28:31 -0700
Message-ID: <CABBYNZLWUM4JJjm5H=f7szt_7bgSFcAknk4AcVUmO5iPJzQVcQ@mail.gmail.com>
Subject: Re: [PATCH] Bluetooth: Always set event mask on suspend
To:     Abhishek Pandit-Subedi <abhishekpandit@google.com>
Cc:     "linux-bluetooth@vger.kernel.org" <linux-bluetooth@vger.kernel.org>,
        Abhishek Pandit-Subedi <abhishekpandit@chromium.org>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Johan Hedberg <johan.hedberg@gmail.com>,
        Marcel Holtmann <marcel@holtmann.org>,
        Paolo Abeni <pabeni@redhat.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "open list:NETWORKING [GENERAL]" <netdev@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hi Abhishek,

On Mon, Jul 25, 2022 at 1:50 PM Abhishek Pandit-Subedi
<abhishekpandit@google.com> wrote:
>
> From: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
>
> When suspending, always set the event mask once disconnects are
> successful. Otherwise, if wakeup is disallowed, the event mask is not
> set before suspend continues and can result in an early wakeup.
>

Please include the commit hash it fixes, also it may be a good idea to
tag it for stable as well.

> Signed-off-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
> ---
> Observed on ChromeOS as follows:
>
> < HCI Command: Disconnect (0x01|0x0006) plen 3
>         Handle: 256
>         Reason: Remote Device Terminated due to Power Off (0x15)
> > HCI Event: Command Status (0x0f) plen 4
>       Disconnect (0x01|0x0006) ncmd 1
>         Status: Success (0x00)
> @ MGMT Event: Device Disconnected (0x000c) plen 8
>         BR/EDR Address: 04:52:C7:C3:65:B5 (Bose Corporation)
>         Reason: Connection terminated by local host for suspend (0x05)
> @ MGMT Event: Controller Suspended (0x002d) plen 1
>         Suspend state: Disconnected and not scanning (1)
> > HCI Event: Disconnect Complete (0x05) plen 4
>         Status: Success (0x00)
>         Handle: 256
>         Reason: Connection Terminated By Local Host (0x16)
>
> The expectation is that we should see Set Event Mask before completing
> the suspend so that the `Disconnect Complete` doesn't wake us up.
>
>
>  net/bluetooth/hci_sync.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
> index 148ce629a59f..e6d804b82b67 100644
> --- a/net/bluetooth/hci_sync.c
> +++ b/net/bluetooth/hci_sync.c
> @@ -5297,6 +5297,9 @@ int hci_suspend_sync(struct hci_dev *hdev)
>                 return err;
>         }
>
> +       /* Update event mask so only the allowed event can wakeup the host */
> +       hci_set_event_mask_sync(hdev);
> +
>         /* Only configure accept list if disconnect succeeded and wake
>          * isn't being prevented.
>          */
> @@ -5308,9 +5311,6 @@ int hci_suspend_sync(struct hci_dev *hdev)
>         /* Unpause to take care of updating scanning params */
>         hdev->scanning_paused = false;
>
> -       /* Update event mask so only the allowed event can wakeup the host */
> -       hci_set_event_mask_sync(hdev);
> -
>         /* Enable event filter for paired devices */
>         hci_update_event_filter_sync(hdev);
>
> --
> 2.37.1.359.gd136c6c3e2-goog
>


-- 
Luiz Augusto von Dentz