Hi,
I would like to provide precise hardware and log details to confirm this
regression on Debian (Trixie). The issue is fully reproducible when
switching between the last two kernel package versions.
*Hardware Details (lsusb):* |Bus 003 Device 002: ID 0489:e0c8 Foxconn /
Hon Hai MediaTek MT7921 Bluetooth|
*Software Environment & Package Versions:*
*
*OS:* Debian 13
*
*Desktop Environment:* KDE Plasma
*
*Working Kernel Package:* |linux-image-6.12.86+deb13-amd64|
(Version: |6.12.86-1|)
*
*Broken Kernel Package:* |linux-image-6.12.88+deb13-amd64| (Version:
|6.12.88-1|)
Comparison of Kernel Logs (dmesg)
1. Working State (Kernel 6.12.86-1)
The controller initializes successfully within ~125ms:
|[ 7.352960] mt7921e 0000:02:00.0: enabling device (0000 -> 0002) [
7.440481] Bluetooth: hci0: HW/SW Version: 0x008a008a, Build Time:
20241106151414 [ 7.451377] mt7921e 0000:02:00.0: WM Firmware Version:
____010000, Build Time: 20241106151045 [ 7.566447] Bluetooth: hci0:
Device setup in 125152 usecs [ 7.566455] Bluetooth: hci0: HCI Enhanced
Setup Synchronous Connection command is advertised, but not supported. [
7.966936] Bluetooth: MGMT ver 1.23 |
/Result: Bluetooth works flawlessly./
2. Broken State (Kernel 6.12.88-1)
Directly after the upgrade, the driver fails during the handshake with
error -22 (Invalid Argument), leading to "No default controller available":
|[ 7.363471] Bluetooth: hci0: HW/SW Version: 0x008a008a, Build Time:
20241106151414 [ 7.379727] mt7921e 0000:02:00.0: enabling device (0000
-> 0002) [ 9.913674] Bluetooth: hci0: Failed to send wmt func ctrl (-22)
[ 9.914709] Bluetooth: hci0: HCI Enhanced Setup Synchronous Connection
command is advertised, but not supported. |
/Result: Bluetooth is completely unavailable in the GUI/bluetoothctl./
Booting back into the 6.12.86-1 entries via GRUB immediately restores
full Bluetooth functionality, confirming a clear regression introduced
in 6.12.88-1.
Regards, Christian
