[Bug 2139683] Re: Bluetooth discovery fails immediately after upgrade to 5.72-0ubuntu5.5 with Realtek RTL8852BU

** Tags added: kernel-daily-bug

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https://bugs.launchpad.net/bugs/2139683

Title:
Bluetooth discovery fails immediately after upgrade to 5.72-0ubuntu5.5
with Realtek RTL8852BU

Status in bluez package in Ubuntu:
New
Status in linux package in Ubuntu:
New

Bug description:
After upgrading from bluez 5.72-0ubuntu5.4 to 5.72-0ubuntu5.5,
Bluetooth device discovery stops working on Realtek RTL8852BU
adapters.

Hardware: Realtek RTL8852BU (USB ID 0bda:4853)
System: Linux Mint 22 (Ubuntu 24.04 base)
Kernel: 6.14.0-37-generic

Symptoms:
- bluetoothctl shows "discovering on" then immediately "discovering off" (cycles repeatedly)
- No Bluetooth devices are found during scan
- Same devices work perfectly with smartphones
- External USB Bluetooth adapter (CSR chip) works perfectly on same system
- Problem appeared immediately after upgrade from 5.72-0ubuntu5.4 to 5.72-0ubuntu5.5

Steps to reproduce:
1. Have system with Realtek RTL8852BU Bluetooth adapter
2. Upgrade bluez from 5.72-0ubuntu5.4 to 5.72-0ubuntu5.5
3. Run: bluetoothctl → power on → scan on
4. Discovery starts and stops immediately, no devices found

Expected behavior: Device discovery should remain active and find nearby Bluetooth devices
Actual behavior: Discovery stops immediately after starting, no devices detected

Workaround: External USB Bluetooth adapter works perfectly, confirming
the issue is specific to the Realtek driver in this bluez version.

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