I've just upgraded from 5.15.30 to 5.17 and now upon pairing my BT headphones I see brand new warning messages I've never seen before: Bluetooth: hci0: unexpected event 0xff length: 25 > 0 Bluetooth: hci0: unexpected event 0xff length: 4 > 0 I wonder if it's a kernel bug or it's a valid message. The BT headphones work without any issues though. The device is 8087:0025 Intel Corp. Wireless-AC 9260 Bluetooth Adapter. # lsmod | grep bt btusb 40960 0 btbcm 20480 1 btusb btintel 32768 1 btusb bluetooth 471040 52 btintel,btbcm,bnep,btusb,rfcomm # dmesg -t | egrep -i "bt|blue" Bluetooth: Core ver 2.22 NET: Registered PF_BLUETOOTH protocol family Bluetooth: HCI device and connection manager initialized Bluetooth: HCI socket layer initialized Bluetooth: L2CAP socket layer initialized Bluetooth: SCO socket layer initialized usbcore: registered new interface driver btusb Bluetooth: hci0: Found device firmware: intel/ibt-18-16-1.sfi Bluetooth: hci0: Boot Address: 0x40800 Bluetooth: hci0: Firmware Version: 86-46.21 Bluetooth: hci0: Firmware already loaded Bluetooth: BNEP (Ethernet Emulation) ver 1.3 Bluetooth: BNEP socket layer initialized Bluetooth: RFCOMM TTY layer initialized Bluetooth: RFCOMM socket layer initialized Bluetooth: RFCOMM ver 1.11 Bluetooth: hci0: unexpected event 0xff length: 25 > 0 Bluetooth: hci0: unexpected event 0xff length: 4 > 0
https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/commit/net/bluetooth/hci_event.c?id=314d8cd2787418c5ac6b02035c344644f47b292b It haven't made to 5.17 though but it is already fixed in bluetooth-next.
(In reply to Luiz Von Dentz from comment #1) > https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/ > commit/net/bluetooth/hci_event.c?id=314d8cd2787418c5ac6b02035c344644f47b292b > > It haven't made to 5.17 though but it is already fixed in bluetooth-next. I'm not sure what to make of this patch (don't quite understand the code - error logging looks to be the same regardless albeit it's rate limited) - I hope to see it applied to future stable releases.
(In reply to Artem S. Tashkinov from comment #2) > (In reply to Luiz Von Dentz from comment #1) > > > https://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next.git/ > > > commit/net/bluetooth/hci_event.c?id=314d8cd2787418c5ac6b02035c344644f47b292b > > > > It haven't made to 5.17 though but it is already fixed in bluetooth-next. > > I'm not sure what to make of this patch (don't quite understand the code - > error logging looks to be the same regardless albeit it's rate limited) - I > hope to see it applied to future stable releases. It does switch to HCI_EV_VENDOR (0xff) to be variable size so it won't be triggering the error, the rate limite is just a safeguard in case some other event start spamming.