apport information
** Tags added: apport-collected resolute
** Description changed:
Bluetooth RTL8723BE not discovering devices on Kubuntu 26.04 (kernel
7.0.0-34)
HARDWARE
Laptop with M.2 Key E combo adapter, Realtek RTL8723BE:
- WiFi: Realtek RTL8723BE PCIe at 06:00.0 (driver rtl8723be) - WORKS
- Bluetooth: internal USB, ID 0930:0222 "Toshiba Corp. Bluetooth Radio"
(driver btusb + btrtl) - DOES NOT WORK
- USB path: 2-11, behind Intel USB controller (pci 00:14.0)
SOFTWARE
- OS: Kubuntu 26.04.1 LTS
- Kernel: 7.0.0-34-generic #34-Ubuntu SMP PREEMPT_DYNAMIC
- bluez: 5.85-4ubuntu0.2
- btusb version: 0.8
- linux-firmware: 20260319.git217ca6e4.1ubuntu
SYMPTOM
The adapter is detected, btusb binds correctly to both interfaces, hci0
reaches
UP RUNNING INQUIRY, and it transmits 163 HCI commands. But it never receives a
single reply. Scanning always returns 0 devices.
Works normally on Windows and on Debian 13 (kernel 6.12). This is Ubuntu 26.04
with kernel 7.0.0 only.
DRIVER BINDING IS CORRECT
2-11:1.0 -> btusb
2-11:1.1 -> btusb
bInterfaceClass/SubClass/Protocol = e0/01/01 (Bluetooth)
btusb alias present: usb:v0930p*d*dc*dsc*dp*icFFisc01ip01in*
HCI STATE
hci0: Type: Primary Bus: USB
BD Address: C8:FF:28:BA:03:F9 ACL MTU: 820:8 SCO MTU: 255:16
UP RUNNING INQUIRY
RX bytes:1870 acl:0 sco:0 events:197 errors:0
TX bytes:6906 acl:0 sco:0 commands:163 errors:0
KERNEL ERRORS
Bluetooth: hci0: urb 00000000019bd5c1 failed to resubmit (2)
bluetoothd[1238]: Failed to set mode: Failed (0x03)
HCI TRACE (btmon)
Commands go out and get Command Complete, but no responses ever come back:
< HCI Command: Inquiry (0x01|0x0001)
> HCI Event: Command Status (0x0f)
< HCI Command: LE Set Scan Enable (0x08|0x000c)
> HCI Event: Command Complete (0x0e)
Response events observed: 0
Inquiry Result: 0
LE Advertising Report: 0
Remote Name Complete: 0
Connection Complete: 0
The controller acknowledges every command but the radio never responds.
HCI ERROR 0x03 = "Hardware General Error" on every boot at bluetoothd
startup.
WHAT WAS RULED OUT
- rfkill soft block: resolved (rfkill unblock + persistent systemd unit), no
change
- USB autosuspend (2000 ms): resolved (power/control=on + udev rule), no
change
- HCI reset via modprobe -r btusb / modprobe btusb: no change
- USB unbind/bind on port 2-11: leaves chip without BD Address
(00:00:00:00:00:00),
only recovers on cold boot
- Cold boot: restores BD Address correctly, still 0 devices found
- Regulatory domain set to AR: no change
- Kernel 7.0.0-30: same btusb 0.8 driver, same failure
- Kernel 6.12.107+deb13-amd64 (Debian 13 kernel, where BT works): does not
boot
in Ubuntu (manually installed .deb, dependency mismatch)
ADDITIONAL CONTEXT
- WiFi half of the same combo card works fine (rtl8723be, firmware
rtlwifi/rtl8723befw_36.bin)
- Chip reports LMP Version 4.0, Subversion 0x8723, Manufacturer Realtek
- linux-firmware contains rtl8723b_config-OBDA8723.bin
QUESTIONS
1. Is there a known regression in btusb or the USB firmware path in kernel
7.0.x
affecting Realtek RTL8723B composite devices, where the radio enters a
zombie
state after HCI error 0x03 and never recovers?
2. Does the Bluetooth half of the RTL8723BE require a specific firmware blob
that Debian loads but Ubuntu does not?
3. Is USB unbind/bind not being sufficient to reset the controller, and is a
cold boot or a different reset procedure required?
+ ---
+ ProblemType: Bug
+ ApportVersion: 2.34.1-0ubuntu0.1
+ Architecture: amd64
+ CasperMD5CheckResult: unknown
+ CurrentDesktop: KDE
+ DistroRelease: Ubuntu 26.04
+ InstallationDate: Installed on 2026-09-25 (11 days ago)
+ InstallationMedia: Kubuntu 26.04.1 LTS "Resolute Raccoon" - Release amd64
(20260826.1)
+ IwDevWlp6s0Link: Not connected.
+ MachineType: Default string Default string
+ NonfreeKernelModules: nvidia_modeset nvidia
+ Package: linux (not installed)
+ ProcFB: 0 nvidia-drmdrmfb
+ ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-7.0.0-38-generic
root=UUID=31bda3fb-4a4b-4ba5-b13a-76d5572c24a7 ro quiet splash
+ ProcVersionSignature: Ubuntu 7.0.0-38.38-generic 7.0.14
+ PulseList: Error: command ['pacmd', 'list'] failed with exit code 1: No
PulseAudio daemon running, or not running as session daemon.
+ Tags: resolute
+ Uname: Linux 7.0.0-38-generic x86_64
+ UpgradeStatus: No upgrade log present (probably fresh install)
+ UserGroups: N/A
+ _MarkForUpload: True
+ dmi.bios.date: 03/06/2023
+ dmi.bios.release: 5.11
+ dmi.bios.vendor: American Megatrends Inc.
+ dmi.bios.version: 5.11
+ dmi.board.asset.tag: Default string
+ dmi.board.name: E5-RS9
+ dmi.board.vendor: MACHINIST
+ dmi.board.version: V1.11
+ dmi.chassis.asset.tag: Default string
+ dmi.chassis.type: 3
+ dmi.chassis.vendor: Default string
+ dmi.chassis.version: Default string
+ dmi.modalias:
dmi:bvnAmericanMegatrendsInc.:bvr5.11:bd03/06/2023:br5.11:svnDefaultstring:pnDefaultstring:pvrDefaultstring:rvnMACHINIST:rnE5-RS9:rvrV1.11:cvnDefaultstring:ct3:cvrDefaultstring:skuDefaultstring:pfaDefaultstring:
+ dmi.product.family: Default string
+ dmi.product.name: Default string
+ dmi.product.sku: Default string
+ dmi.product.version: Default string
+ dmi.sys.vendor: Default string
** Attachment added: "AlsaInfo.txt"
https://bugs.launchpad.net/bugs/2169036/+attachment/6006291/+files/AlsaInfo.txt
--
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2169036
Title:
Bluetooth RTL8723BE (USB 0930:0222) never discovers any devices on
26.04 (kernel 7.0.0-34)
To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2169036/+subscriptions
--
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
