Re: [BUG] BLE device unpairing triggers kernel panic

[Luiz Augusto von Dentz <luiz.dentz@gmail.com>]

Hi Ahmad,

On Fri, Jun 24, 2022 at 5:53 AM Ahmad Fatoum <a.fatoum@pengutronix.de> wrote:
>
> Hi Tedd, Luiz,
>
> On 21.06.22 20:52, Luiz Augusto von Dentz wrote:
> > Hi Ahmad, Tedd,
> >
> > On Tue, Jun 21, 2022 at 1:32 AM Ahmad Fatoum <a.fatoum@pengutronix.de> wrote:
> >>
> >> Hello Luiz,
> >>
> >> On 20.06.22 22:18, Luiz Augusto von Dentz wrote:
> >>> On Mon, Jun 20, 2022 at 3:06 AM Ahmad Fatoum <a.fatoum@pengutronix.de> wrote:
> >>>> Disconnect of connection #1 being processed after new connection #2
> >>>> concluded sounds wrong. Would I be able to reconnect
> >>>> afterwards or would all connections, but the first, be directly
> >>>> disconnected...?
> >>>
> >>> That depends on the order you have queued the commands, it will be
> >>> processed in the exact order it is received, that why I said it is
> >>> single queue design, and it is done like that to prevent messing up
> >>> with states since we know the exact order the commands will be sent.
> >>>
> >>>>> otherwise we need a
> >>>>> different queue to handle command that abort/cancel other already in
> >>>>> the queue.
> >>>>
> >>>> Is the revert an acceptable interim solution or are there issues
> >>>> I am missing?
> >>>
> >>> Afaik there were problem with concurrent connections request, so what
> >>> would really help us here is to have some tests to emulate this
> >>> scenario with our CI, in the meantime please check if the following
> >>> fixes your problem:
> >>>
> >>> https://gist.github.com/Vudentz/b4fff292c7f4ad55ca3299fd5ab797ae
> >>
> >> Doesn't help unfortunately. First pairing works as before.
> >> Second still fails:
> >>
> >>   Bluetooth: hci0: Opcode 0x200d failed: -110
> >>   Bluetooth: hci0: request failed to create LE connection: err -110
> >
> > Can we try to add a test in mgmt-tester to reproduce the error above?
>
> I am not familiar with mgmt-tester. What information do you
> need to reproduce? In the meantime, can we revert the commit?
> I understand that this may break other uses, but I believe
> previously working stuff should have precedence..

Have a looks at:

https://git.kernel.org/pub/scm/bluetooth/bluez.git/tree/doc/test-runner.txt

And then run with:

sudo tools/test-runner -k <pathyto/bzImage> -- tools/mgmt-tester

Btw, can we have the exact steps to reproduce it using bluetoothctl if possible?

> Cheers,
> Ahmad
>
> >
> >> Cheers,
> >> Ahmad
> >>
> >>>
> >>>> Cheers,
> >>>> Ahmad
> >>>>
> >>>>>
> >>>>>> We've been deploying the revert for a while now and I just posted
> >>>>>> it to the mailing list[1]. There have been other reports
> >>>>>> of this issue with different hardware too and fixing sent_cmd
> >>>>>> would likely be too complicated/time intensive for me.
> >>>>>>
> >>>>>> I am happy to test future patches that fix this properly though.
> >>>>>>
> >>>>>> [1]: https://lore.kernel.org/linux-bluetooth/20220616092418.738877-1-a.fatoum@pengutronix.de/T/#t
> >>>>>>
> >>>>>> Cheers,
> >>>>>> Ahmad
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>>>>
> >>>>>>> Cheers,
> >>>>>>> Ahmad
> >>>>>>>
> >>>>>>
> >>>>>>
> >>>>>> --
> >>>>>> Pengutronix e.K.                           |                             |
> >>>>>> Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
> >>>>>> 31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
> >>>>>> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |
> >>>>>
> >>>>>
> >>>>>
> >>>>
> >>>>
> >>>> --
> >>>> Pengutronix e.K.                           |                             |
> >>>> Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
> >>>> 31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
> >>>> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |
> >>>
> >>>
> >>>
> >>
> >>
> >> --
> >> Pengutronix e.K.                           |                             |
> >> Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
> >> 31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
> >> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |
> >
> >
> >
>
>
> --
> Pengutronix e.K.                           |                             |
> Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
> 31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |



-- 
Luiz Augusto von Dentz