lkml.org 
[lkml]   [2019]   [Mar]   [20]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [RFC] Bluetooth: Retry configure request if result is L2CAP_CONF_UNKNOWN
On Mon, Feb 18, 2019 at 8:57 PM Andrey Smirnov <andrew.smirnov@gmail.com> wrote:
>
> On Mon, Feb 18, 2019 at 4:58 AM Marcel Holtmann <marcel@holtmann.org> wrote:
> >
> > Hi Andrey,
> >
> > > 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. Store a mask of supported conf option types per connection
> > >
> > > 2. Parse the body of response L2CAP_CONF_UNKNOWN and adjust
> > > connection's supported conf option types mask
> > >
> > > 3. Retry configuration step the same way it's done for
> > > L2CAP_CONF_UNACCEPT
> > >
> > > Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> > > Cc: Pierre-Loup A. Griffais <pgriffais@valvesoftware.com>
> > > Cc: Florian Dollinger <dollinger.florian@gmx.de>
> > > Cc: Marcel Holtmann <marcel@holtmann.org>
> > > Cc: Johan Hedberg <johan.hedberg@gmail.com>
> > > Cc: linux-bluetooth@vger.kernel.org
> > > Cc: linux-kernel@vger.kernel.org
> > > ---
> > >
> > > Everyone:
> > >
> > > I marked this as an RFC, since I don't have a lot of experience with
> > > Bluetooth subsystem and don't have hight degree of confidence about
> > > choices made in this patch. I do, however, thins is is good enough to
> > > start a discussion about the problem.
> >
> > can you take a btmon -w trace.log protocol trace so that I can see where it fails. This seems a really odd behavior of the Xbox controller. We have to be careful in not breaking Bluetooth qualification to just workaround some buggy remote device.
> >
>
> Sure, n/p, both "failure" (behavior before this patch) and "success"
> (behavior with the patch) cases on my machine are available here:
>
> https://gist.github.com/ndreys/2b74094933601978e200af1ff0a55372
>
> Let me know if that's not accessible to you.
>

Marcel, did you have a chance to look at the logs?

Thanks,
Andrey Smirnov

\
 
 \ /
  Last update: 2019-03-21 00:09    [W:0.079 / U:0.108 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site