Re: [PATCH v2] Bluetooth: Retry configure request if result is L2CAP_CONF_UNKNOWN

[Andrey Smirnov]

On Tue, May 21, 2019 at 6:31 PM Andrey Smirnov <andrew.smirnov@xxxxxxxxx> wrote:
>
> Due to:
>
>  * Current implementation of l2cap_config_rsp() dropping BT
>    connection if sender of configuration response replied with unknown
>    option failure (Result=0x0003/L2CAP_CONF_UNKNOWN)
>
>  * Current implementation of l2cap_build_conf_req() adding
>    L2CAP_CONF_RFC(0x04) option to initial configure request sent by
>    the Linux host.
>
> devices that do no recongninze L2CAP_CONF_RFC, such as Xbox One S
> controllers, will get stuck in endless connect -> configure ->
> disconnect loop, never connect and be generaly unusable.
>
> To avoid this problem add code to do the following:
>
>  1. Parse the body of response L2CAP_CONF_UNKNOWN and, in case of
>     unsupported option being RFC, clear L2CAP_FEAT_ERTM and
>     L2CAP_FEAT_STREAMING from connection's feature mask (in order to
>     prevent RFC option from being added going forward)
>
>  2. Retry configuration step the same way it's done for
>     L2CAP_CONF_UNACCEPT
>
> Signed-off-by: Andrey Smirnov <andrew.smirnov@xxxxxxxxx>
> Cc: Pierre-Loup A. Griffais <pgriffais@xxxxxxxxxxxxxxxxx>
> Cc: Florian Dollinger <dollinger.florian@xxxxxx>
> Cc: Marcel Holtmann <marcel@xxxxxxxxxxxx>
> Cc: Johan Hedberg <johan.hedberg@xxxxxxxxx>
> Cc: linux-bluetooth@xxxxxxxxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> ---
>
> Changes since [v1]:
>
>    - Patch simplified to simply clear L2CAP_FEAT_ERTM |
>      L2CAP_FEAT_STREAMING from feat_mask when device flags RFC options
>      as unknown
>
> [v1] lore.kernel.org/r/20190208025828.30901-1-andrew.smirnov@xxxxxxxxx
>

Pinging the status of this. Marcel, do you have any feedback on v2?

Thanks,
Andrey Smirnov