Hi, After updating Linux on an i.MX28 board, I encountered errors related to Bluetooth: $ journalctl -p3 -xb (...) Feb 06 14:05:49 hp1 bluetoothd[183]: /usr/src/debug/bluez5/5.69-r0/src/adapter.c:reset_adv_monitors_complete() Failed to reset Adv Monitors: Failed (0x03) Feb 06 14:05:50 hp1 bluetoothd[183]: Failed to clear UUIDs: Failed (0x03) Feb 06 14:05:50 hp1 bluetoothd[183]: Failed to add UUID: Failed (0x03) Feb 06 14:05:50 hp1 bluetoothd[183]: Failed to add UUID: Failed (0x03) Feb 06 14:05:50 hp1 bluetoothd[183]: Failed to add UUID: Failed (0x03) I found that [1] encountered similar errors, which were addressed in 95b701543305 ("Bluetooth: btusb: Fix bluetooth on Intel Macbook 2014"). However, the board I am working with uses the Bluetooth HCI UART driver instead of the USB driver. After bisecting, I identified the offending commit as d883a4669a1d ("Bluetooth: hci_sync: Only allow hci_cmd_sync_queue if running"). While reverting the commit would resolve my issues, I am uncertain if this problem is unique to my setup, as I have not come across other reports for ARM boards or the Bluetooth HCI UART driver. Do you have any ideas how to solve this? Any pointers are appreciated. Below is (some) of the log when running the daemon in debug mode. I only included part of it to not clutter the mail. Let me know if you want the full log instead. $ /usr/libexec/bluetooth/bluetoothd -n -d (...) bluetoothd[384]: /usr/src/debug/bluez5/5.69-r0/src/shared/mgmt.c:send_request() [0x0000] command 0x0053 bluetoothd[384]: /usr/src/debug/bluez5/5.69-r0/src/shared/mgmt.c:can_read_data() [0x0000] command 0x53 status: 0x03 bluetoothd[384]: /usr/src/debug/bluez5/5.69-r0/src/adapter.c:reset_adv_monitors_complete() Failed to reset Adv Monitors: Failed (0x03) bluetoothd[384]: /usr/src/debug/bluez5/5.69-r0/src/shared/mgmt.c:send_request() write failed: Network is down bluetoothd[384]: Failed to clear UUIDs: Failed (0x03) bluetoothd[384]: /usr/src/debug/bluez5/5.69-r0/src/shared/mgmt.c:send_request() write failed: Network is down bluetoothd[384]: Failed to add UUID: Failed (0x03) And here is some information about the device. Note that I anonymized the MAC address. $ hciconfig -a hci0: Type: Primary Bus: UART BD Address: XX:XX:XX:XX:XX:XX ACL MTU: 1021:6 SCO MTU: 180:4 UP RUNNING RX bytes:5761 acl:0 sco:0 events:494 errors:0 TX bytes:70546 acl:0 sco:0 commands:494 errors:0 Features: 0xff 0xfe 0x2d 0xfe 0xdb 0xff 0x7b 0x87 Packet type: DM1 DM3 DM5 DH1 DH3 DH5 HV1 HV2 HV3 Link policy: RSWITCH HOLD SNIFF Link mode: PERIPHERAL ACCEPT Name: 'BlueZ 5.69' Class: 0x000000 Service Classes: Unspecified Device Class: Miscellaneous, HCI Version: 4.2 (0x8) Revision: 0x0 LMP Version: 4.2 (0x8) Subversion: 0xac0f Manufacturer: Texas Instruments Inc. (13) Let me know if I can provide more information. [1]: https://bugs.archlinux.org/task/78980.html -- Emil Kronborg