Public bug reported: Bluetooth was working correctly on linux-image-6.8.0-139.139. After updating to linux-image-6.8.0-142.142, Bluetooth stopped working entirely — the adapter fails to initialize and no devices can be discovered or paired. Reverting to 6.8.0-139-generic restores full functionality, confirming this is a regression introduced somewhere between those two kernel versions.
Source package: linux (Ubuntu) Release: $ lsb_release -rd Description: Linux Mint 22.3 Release: 22.3 (Linux Mint 22.3 "Zena", based on Ubuntu 24.04 "Noble") Package versions: $ apt-cache policy linux-image-6.8.0-142-generic linux-image-6.8.0-142-generic: Installed: 6.8.0-142.142 Candidate: 6.8.0-142.142 500 http://archive.ubuntu.com/ubuntu noble-updates/main amd64 Packages $ apt-cache policy linux-image-6.8.0-139-generic linux-image-6.8.0-139-generic: Installed: 6.8.0-139.139 Candidate: 6.8.0-139.139 500 http://archive.ubuntu.com/ubuntu noble-updates/main amd64 Packages 500 http://security.ubuntu.com/ubuntu noble-security/main amd64 Packages version_signature (currently booted, working kernel): $ cat /proc/version_signature Ubuntu 6.8.0-139.139-generic 6.8.12 uname -a: Linux bigMac 6.8.0-139-generic #139-Ubuntu SMP PREEMPT_DYNAMIC Sat Aug 1 03:52:05 UTC 2026 x86_64 x86_64 x86_64 GNU/Linux Hardware: Model: MacBookPro12,1 (product_version 1.0, firmware 489.0.0.0.0) Bluetooth chip: Broadcom BCM20703 (internal, USB ID 05ac:8290) Wi-Fi chip (for reference, from lspci): Broadcom BCM43602 802.11ac [14e4:43ba] lspci -vnvn (Wi-Fi/network controller shown; Bluetooth is USB-attached, not PCI, so it doesn't appear here): 03:00.0 Network controller [0280]: Broadcom Inc. and subsidiaries BCM43602 802.11ac Wireless LAN SoC [14e4:43ba] (rev 01) Subsystem: Apple Inc. BCM43602 802.11ac Wireless LAN SoC [106b:0133] Capabilities: [48] Power Management version 3 Capabilities: [58] MSI: Enable+ Count=1/16 Maskable- 64bit+ Capabilities: [68] Vendor Specific Information: Len=44 <?> Capabilities: [ac] Express (v2) Endpoint, MSI 00 (Full lspci-vnvn.log attached separately) Steps to reproduce: Boot into 6.8.0-142-generic Confirm Bluetooth service is active: systemctl status bluetooth shows running Confirm not blocked: rfkill list shows Soft blocked: no, Hard blocked: no Run hciconfig -a — adapter shows DOWN with a zeroed BD Address Expected result: Bluetooth adapter initializes with a valid BD Address, shows UP RUNNING, and can scan/pair with devices. Actual result on broken kernel (6.8.0-142-generic): hci0: Type: Primary Bus: USB BD Address: 00:00:00:00:00:00 ACL MTU: 0:0 SCO MTU: 0:0 DOWN RX bytes:0 acl:0 sco:0 events:0 errors:0 TX bytes:0 acl:0 sco:0 commands:1 errors:1 Relevant dmesg output on broken kernel: [ 1.360619] usb 1-3: Product: Bluetooth USB Host Controller [ 1.384678] input: Broadcom Corp. Bluetooth USB Host Controller as /devices/pci0000:00/0000:00:14.0/usb1/1-3/1-3:1.0/0003:05AC:8290.0001/input/input4 [ 3.642798] Bluetooth: Core ver 2.22 [ 3.642825] Bluetooth: HCI device and connection manager initialized [ 5.877444] Bluetooth: hci0: command 0x0c03 tx timeout [ 5.877459] Bluetooth: hci0: BCM: Reset failed (-110) Working result on 6.8.0-139-generic: hci0: Type: Primary Bus: USB BD Address: A4:5E:60:D3:83:92 ACL MTU: 1021:8 SCO MTU: 64:1 UP RUNNING PSCAN Manufacturer: Broadcom Corporation (15) HCI Version: 4.2 (0x8) Revision: 0x12d9 LMP Version: 4.2 (0x8) Subversion: 0x21a9 Workaround: Booting 6.8.0-139-generic instead of 6.8.0-142-generic restores full Bluetooth functionality. Set as persistent default via grub-set-default with GRUB_DEFAULT=saved in /etc/default/grub. Additional notes: This hardware has explicit named support in the btusb/btbcm kernel driver dating back to when BCM20703 support was first added for early-2015 MacBook Pro models. A separate upstream kernel patch from early 2025 addressed a related BCM: Reset failed (-110) timing issue by adding a warmup delay before the reset command — worth checking whether that fix is present in 6.8.0-142-generic or whether this is a distinct regression. ** Affects: linux (Ubuntu) Importance: Undecided Status: New ** Attachment added: "lspci-vnvn.log" https://bugs.launchpad.net/bugs/2168259/+attachment/6002018/+files/lspci-vnvn.log -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/2168259 Title: Bluetooth broken on MacBookPro12,1 (Broadcom BCM20703) after upgrading to linux-image-6.8.0-142-generic To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2168259/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
