LAN over Bluetooth failure with 5.3-STABLE

[Petr Panteleyev]

I'm trying to connect WinXP with 5.3-STABLE via
Bluetooth using USB dongles.

I followed Handbook, set up and started rc.bluetooth, hcsecd, sdpd
and rfcomm_pppd. My dongle is recognized, pairing goes well.

Connection from WinXP to FreeBSD can be always established but when
I'm trying to send any data over this connection, it drops very soon
with the following diagnostics:

Jan 22 21:34:49 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x4, len=124. Queue full
Jan 22 21:34:49 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x4, len=13. Queue full
Jan 22 21:34:49 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x4, len=124. Queue full
Jan 22 21:34:49 elrond last message repeated 3 times
Jan 22 21:34:49 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x4, len=13. Queue full
Jan 22 21:47:37 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x6, len=124. Queue full
Jan 22 21:47:37 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x6, len=13. Queue full
Jan 22 21:47:37 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x6, len=124. Queue full
Jan 22 21:47:37 elrond last message repeated 2 times
Jan 22 21:47:37 elrond kernel: ng_ubt_rcvdata: ubt0 - Dropping HCI frame 
0x6, len=13. Queue full
Jan 22 21:47:46 elrond kernel: ng_btsocket_rfcomm_session_send: Could 
not send data to L2CAP socket, error=40
Jan 22 21:47:46 elrond kernel: ng_l2cap_l2ca_receive: ubt0l2cap - 
unexpected L2CAP data packet. Invalid channel state, cid=75, state=5

I tried to reduce MTU and MRU for ppp down to 512. It helped a bit -
connection was alive a bit longer. Then again, connection dropped with
the above diagnostics.

Just have no idea where to dig further.

Regards,
Petr