Re: When connecting to NAP bnep0 can not go up

[Ferry Toth <ftoth@exalondelft.nl>]

Adding Andy, Marcel, Johan to CC

Op 16-02-19 om 18:38 schreef Ferry Toth:
> I'm trying to make a connection from my Edison (linux 4.19) to my android
> phone (nap), but it seems Edison bnep0 gets removed immediately after
> creation. How can help me diagnose this?

Actually, this is using Andy's kernel 4.20 (not 4.19).

I didn't mention that other BT functionality seems to be working fine. 
And building with Yocto Thud (bluez 5.50).

Everything is fairly up-to-date (compared to Edison factory image).

> Initially I tried connman. The bluetooth service appears, but when I 
> try to
> connect I get:
>
> connmanctl> connect bluetooth_43341B001FAC_C462EA01AF74
> Error /net/connman/service/bluetooth_43341B001FAC_C462EA01AF74:
> Input/output error
>
> For testing I switched to the bluez test-network.py script:
>
> root@edison:~# python3 ./test-network.py C4:62:EA:01:AF:74 nap
> Traceback (most recent call last):
>   File "./test-network.py", line 42, in <module>
>     iface = network.Connect(service)
>   File "/usr/lib/python3.5/site-packages/dbus/proxies.py", line 70, in
> __call__
>     return self._proxy_method(*args, **keywords)
>   File "/usr/lib/python3.5/site-packages/dbus/proxies.py", line 145, in
> __call__
>     **keywords)
>   File "/usr/lib/python3.5/site-packages/dbus/connection.py", line 
> 651, in
> call_blocking
>     message, timeout)
> dbus.exceptions.DBusException: org.bluez.Error.Failed: Input/output error
>
> Using btmon to log while running above script:
>
> < ACL Data TX: Handle 12 flags 0x00 dlen 11
> #96 [hci0] 2974.047858
>       Channel: 78 len 7 [PSM 15 mode 0] {chan 0}
>       BNEP: Control (0x01|0)
>          Setup Conn Req (0x01)
>            Size: 0x02
>            Dst: 0x1116(NAP)
>            Src: 0x1115(PANU)
>> HCI Event: Number of Completed Packets (0x13) plen 5
> #97 [hci0] 2974.049982
>         Num handles: 1
>         Handle: 12
>         Count: 2
>> ACL Data RX: Handle 12 flags 0x02 dlen 8
> #98 [hci0] 2974.052464
>       Channel: 64 len 4 [PSM 15 mode 0] {chan 0}
>       BNEP: Control (0x01|0)
>          Setup Conn Rsp (0x02)
>            Rsp msg: Operation Successful(0x0000)
> = bluetoothd: bnep: Could not bring up bnep0: Cannot assign requested
> address(99)
> = bluetoothd: connect failed Input/output error
>
> And logging with udevadm monitor:
> KERNEL add /devices/pci..../serial0-0/bluetooth/hci0/hci0:12 (bluetooth)
> UDEV   add /devices/pci..../serial0-0/bluetooth/hci0/hci0:12 (bluetooth)
> KERNEL add /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0 
> (net)
> KERNEL add
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/rx-0
> (queues)
> KERNEL add
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/tx-0
> (queues)
> KERNEL remove
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/rx-0
> (queues)
> KERNEL[146116.687930] remove
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/tx-0
> (queues)
> KERNEL 
> remove   /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0
> (net)

Note the KERNEL already issues a remove before UDEV add

> UDEV   add      /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0 
>
> (net)
> UDEV   add
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/rx-0
> (queues)
> UDEV   add
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/tx-0
> (queues)
> UDEV   remove
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/rx-0
> (queues)
> UDEV  [146116.776687] remove
> /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0/queues/tx-0
> (queues)
> UDEV   remove   /devices/pci..../serial0-0/bluetooth/hci0/hci0:12/net/bnep0 
>
> (net)
> KERNEL remove   /devices/pci..../serial0-0/bluetooth/hci0/hci0:12
> (bluetooth)
> UDEV   remove   /devices/pci..../serial0-0/bluetooth/hci0/hci0:12
> (bluetooth)
>
> To me it looks like the kernel already removes the bnep0 device, 
> before user
> space can bring it up.
>
> And indeed, doing the same from another computer (Ubuntu linux 4.18) I 
> get
> only the kernel and udev add events, the connection is established and 
> the
> remove events appear only after pressing Ctrl-C
>
> What could this be?
>
>