Return-Path: MIME-Version: 1.0 In-Reply-To: <0C972A55-F518-47CD-A9DC-FF23B1218B0B@holtmann.org> References: <614A5683-0763-4E64-B178-67577793D8EF@holtmann.org> <51DF00FF-73E9-4E94-A89A-86EBD7220068@holtmann.org> <147B282F-6EBF-4F3A-A74E-33D5A9F54AE9@holtmann.org> <0C972A55-F518-47CD-A9DC-FF23B1218B0B@holtmann.org> Date: Fri, 9 Oct 2015 14:50:05 -0700 Message-ID: Subject: Re: Issue with new LE connection creation From: Jakub Pawlowski To: Marcel Holtmann Cc: linux-bluetooth Content-Type: text/plain; charset=UTF-8 List-ID: Hi Marcel, On Fri, Oct 9, 2015 at 2:44 PM, Marcel Holtmann wrote= : > Hi Jakub, > >>>>>> so when I try to connect a LE L2CAP connection to a device that does= not exist and then abort it will not have reached the timeout, I get this: >>>>>> >>>>>> < HCI Command: LE Add Device To White List (0x08|0x0011) plen 7 >>>>>> Address type: Public (0x00) >>>>>> Address: 11:22:33:44:55:66 (OUI 11-22-33) >>>>>>> HCI Event: Command Complete (0x0e) plen 4 >>>>>> LE Add Device To White List (0x08|0x0011) ncmd 1 >>>>>> Status: Success (0x00) >>>>>> < HCI Command: LE Set Scan Parameters (0x08|0x000b) plen 7 >>>>>> Type: Passive (0x00) >>>>>> Interval: 60.000 msec (0x0060) >>>>>> Window: 30.000 msec (0x0030) >>>>>> Own address type: Public (0x00) >>>>>> Filter policy: Ignore not in white list (0x01) >>>>>>> HCI Event: Command Complete (0x0e) plen 4 >>>>>> LE Set Scan Parameters (0x08|0x000b) ncmd 1 >>>>>> Status: Success (0x00) >>>>>> < HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 >>>>>> Scanning: Enabled (0x01) >>>>>> Filter duplicates: Enabled (0x01) >>>>>>> HCI Event: Command Complete (0x0e) plen 4 >>>>>> LE Set Scan Enable (0x08|0x000c) ncmd 1 >>>>>> Status: Success (0x00) >>>>>> < HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 >>>>>> Scanning: Disabled (0x00) >>>>>> Filter duplicates: Disabled (0x00) >>>>>>> HCI Event: Command Complete (0x0e) plen 4 >>>>>> LE Set Scan Enable (0x08|0x000c) ncmd 1 >>>>>> Status: Success (0x00) >>>>>> < HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 >>>>>> Scanning: Disabled (0x00) >>>>>> Filter duplicates: Disabled (0x00) >>>>>>> HCI Event: Command Complete (0x0e) plen 4 >>>>>> LE Set Scan Enable (0x08|0x000c) ncmd 1 >>>>>> Status: Command Disallowed (0x0c) >>>>>> >>>>>> Notice the two attempts for disabling scanning. We should not do tha= t. This is clearly a bug. This can be easily reproduced with latest bluetoo= th-next and this command: >>>>>> >>>>>> l2test -V le_public -n 11:22:33:44:55:66 >>>>>> >>>>>> The same happens when you are waiting for the socket connect timeout= . The scanning disable command is sent twice. >>>>>> >>>>>> I also had a case where the disabling of the scanning is not sent at= all and the controller kept scanning. However for that one, I do not have = an easy way to reproduce it. But it is essentially the same case, you close= the socket / application before the connection has been established. >>>>> >>>>> in addition when a connect() for LE L2CAP socket call times out, we g= et an invalid module reference count. >>>>> >>>>> bluetooth 532480 1 >>>>> rfkill 24576 1 bluetooth >>>>> >>>>> I see it left with an extra reference count. This is pretty bad and s= hows that something is clearly wrong. >>>> >>>> please also look into this. We are not clearing the reference count co= rrectly when aborting a connection attempt while still in scanning phase. >>>> >>> Ok, I'll look into that >> >> So I think that patch I've send fixed that. >> I run tools/l2test -V le_public -n 11:22:33:44:55:66 >> and kill it, or wait for timeout, and reference count always drops >> down to same initial value as before running that command. > > have you tried to unload all modules. Including bluetooth.ko? > Ok, now I see the problem :) thanks. > Regards > > Marcel >