Hi Stefan, >>>>>>> After enabling bluetooth scanning i will see these error messages periodically: >>>>>>> >>>>>>> [ 815.939839] Bluetooth: hci0: last event is not cmd complete (0x0f) >>>>>>> [ 831.302476] Bluetooth: hci0: last event is not cmd complete (0x0f) >>>>>>> [ 847.303953] Bluetooth: hci0: last event is not cmd complete (0x0f) >>>>>>> [ 863.305284] Bluetooth: hci0: last event is not cmd complete (0x0f) >>>>>>> [ 879.306838] Bluetooth: hci0: last event is not cmd complete (0x0f) >>>>>> I really need to hook up the error messages into the btmon output since then we can trace where these are coming from. Anyway, can you btmon -w trace.log from before loading the module and this error showing up. >>>>> I attached the log. According to dmesg this error happend only once during the trace. >>>> I will add bt_dev_err tracing to be include in btmon and that way we can figure out where that error happens. Or do you have a trace.log and dmesg -T where we can correlate it based on time. >>> Please look at this attachment and the following output (issue appears every 16 seconds after enabling scanning even if i use a baudrate of 115200): >>> >>> 2018-02-23T14:12:52,454443+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:13:08,454601+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:13:24,453167+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:13:40,453414+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:13:56,453859+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:14:12,453864+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:14:28,453966+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:14:44,455381+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:15:00,452972+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:15:16,453733+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:15:32,453318+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:15:48,453495+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:16:04,452430+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:16:20,452531+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:16:36,452813+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> 2018-02-23T14:16:52,453043+0100 Bluetooth: hci0: last event is not cmd complete (0x0f) >>> >>> I also noticed a different issue (only tested 4.15 yet), sometimes if i try to unload "modprobe -r hci_uart" the command blocks forever. There is no crash just the command hangs. >> so it seems that this matched up to the set scan enable command. > Hm, i only enabled the scanning once. Does bluetoothctl send this command periodically every 16 seconds? yes, it does interleaved scanning on LE and then BR/EDR. Hence the switch from LE Set Scan Enable to Inquiry etc. >> < HCI Command: LE Set Scan Enable (0x08|0x000c) plen 2 #415 [hci0] 2018-02-23 14:12:52.478963 >> Scanning: Disabled (0x00) >> Filter duplicates: Disabled (0x00) >>> HCI Event: Command Complete (0x0e) plen 4 #416 [hci0] 2018-02-23 14:12:52.483769 >> LE Set Scan Enable (0x08|0x000c) ncmd 1 >> Status: Success (0x00) >> >> Does this happen with all baud rates or just with 115200? > > I've seen this at 115200 and 2000000 baud. This could be well our issue. I need to check if I can reproduce it. I assume you use bluetoothctl for enabling scanning. Wonder what happens if you do it only on LE. So “menu scan” and then “transport le”. I think it is really just the switch from LE to BR/EDR where this happens. Regards Marcel -- To unsubscribe from this list: send the line "unsubscribe linux-bluetooth" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
