bluez 5.30: "Not enough free handles to register service" error in starting bluetoothd

Question

What I have done correctly: in linux environment

1. hciattach /dev/ttyUSB0 any 115200
2. hciconfig hci0 up
3. addgroup -S messagebus
4. adduser -S messagebus -G messagebus
5. dbus-daemon --system

6. syslogd

   In executing /libexec/bluetooth/bluetoothd --plugin=time -d -E -n, The error Not enough free handles to register service happens as below:

   bluetoothd[756]: src/adapter.c:clear_uuids() sending clear uuids command for index 0  <br/>
   bluetoothd[756]: src/adapter.c:set_mode() sending set mode command for index 0 <br/>
   bluetoothd[756]: src/gatt-database.c:btd_gatt_database_new() GATT Manager registered for adapter: /org/bluez/hci0 <br/>
   bluetoothd[756]: src/adapter.c:adapter_service_add() /org/bluez/hci0 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Adding record with handle 0x10002 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00000007-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00000100-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00001002-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00001800-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/adapter.c:adapter_service_insert() /org/bluez/hci0 <br/>
   bluetoothd[756]: src/adapter.c:add_uuid() sending add uuid command for index 0 <br/>
   bluetoothd[756]: src/gatt-database.c:gatt_db_service_added() GATT Service added to local database <br/>
   bluetoothd[756]: Failed to obtain handles for "Service Changed"  characteristic <br/>
   bluetoothd[756]: src/adapter.c:adapter_service_add() /org/bluez/hci0 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Adding record with handle 0x10003 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00000007-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00000100-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00001002-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/sdpd-service.c:add_record_to_server() Record pattern UUID 00001801-0000-1000-8000-00805f9 <br/>
   bluetoothd[756]: src/adapter.c:adapter_service_insert() /org/bluez/hci0 <br/>
   bluetoothd[756]: src/adapter.c:add_uuid() sending add uuid command for index 0 <br/>
   bluetoothd[756]: src/gatt-database.c:gatt_db_service_added() GATT Service added to local database <br/>
   bluetoothd[756]: src/advertising.c:btd_advertising_manager_new() LE Advertising Manager created for adapter: /org/bluez/hci0 <br/>
   bluetoothd[756]: profiles/time/server.c:time_server_init() path /org/bluez/hci0 <br/>
   bluetoothd[756]: src/attrib-server.c:attrib_db_find_avail() enter! <br/>
   bluetoothd[756]: src/attrib-server.c:attrib_db_find_avail() BT_UUID16! <br/>
   ***bluetoothd[756]: Not enough free handles to register service*** <br/>
   bluetoothd[756]: Current Time Service could not be registered <br/>
   bluetoothd[756]: gatt-time-server: Input/output error (5) <br/>
   

I dived into the code for debugging the issue a little bit. The attrib_db_find_avail(adapter, svc_uuid, size)[in function: gatt_service_add()] always return 0.

The root cause is the servers glist parameter is always NULL, which is in g_slist_find_custom(servers, adapter, adapter_cmp)[called from find_uuid16_avail()/find_uuid128_avail()].

I noticed there is the call: **btd_adapter_gatt_server_start**(struct btd_adapter *adapter)to be used to add a server into the servers glist. But the weird thing is no where it gets called through the whole bluez source code tree.

So shall I call btd_adapter_gatt_server_start() somewhere in my code? Or any other steps I should do to resolve the issue?

Solution 1

I was having trouble with bluetooth as well. In my case I was receiving the following error messages several times a minute, as my device went up and down intermitently:

bluetoothd[3196]: Failed to obtain handles for "Service Changed" characteristic
bluetoothd[3196]: Endpoint registered: sender=:1.51 path=/MediaEndpoint/A2DPSource
bluetoothd[3196]: Endpoint registered: sender=:1.51 path=/MediaEndpoint/A2DPSink
bluetoothd[3196]: Failed to set mode: Failed (0x03)

After some research, I found out this thread, where some people fixed their bluetooth problems by deleting ~/.config/pulse. It also solved the problem for me.

I don't have a explanation for why this works, but I'm leaving this tip because it may solve other people's issues as well.

Solution 2

Also you can try to check rfkill service. It could block connections sometime for lan, wifi and bluetooth You can check of what is blocked by this command: rfkill list

My bluetooth was blocked. I used this command:

rfkill unblock bluetooth

Solution 3

rfkill is a subsystem that manages the power to the various radio transmitters that your device might have (such as wifi and bluetooth). It has the ability to manage these devices with software switches (so that they can be temporarily disabled such as to save power) or hardware switches (which might need a reboot to re-enable). rfkill has a command line interface which enables you to control this subsystem. More info can be found from Red Hat https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/power_management_guide/rfkill

It is highly likely that your bluetooth is blocked by rfkill which can be called by power management.