[Bug 221346] New: Bluetooth: btintel_pcie (8086:e476) may hang in shutdown path (synchronize_irq) during reboot stress test

bugzilla-daemon
2026-04-11T12:38:58Z

Bug ID: 221346
Summary: Bluetooth: btintel_pcie (8086:e476) may hang in
shutdown path (synchronize_irq) during reboot stress
test
Product: Drivers
Version: 2.5
Hardware: Intel
OS: Linux
Status: NEW
Severity: normal
Priority: P3
Component: Bluetooth
Assignee: linux-bluetooth@vger.kernel.org
Reporter: zhangzhigang1996@gmail.com
Regression: No

On a system with Intel Bluetooth device [8086:e476] using the btintel_pcie
driver, the system intermittently hangs during reboot or shutdown, especially
under stress test conditions (continuous reboot cycles).

During shutdown, systemd-udevd is observed to be stuck in D state. Kernel
stack traces show the task blocked in the driver removal path, waiting in
synchronize_irq() after free_irq() is called.

The relevant call trace is:

btintel_pcie_remove()
→ free_irq()
→ synchronize_irq()
→ __synchronize_irq()
→ wait for IRQ handler completion (never returns)

This indicates that the interrupt handler associated with the device may not
be properly quiesced before free_irq(), leading to a deadlock during teardown.

The issue is reproducible and disappears when the btintel_pcie module is
unloaded or blacklisted, suggesting the problem is specific to the btintel_pcie
driver.

No firmware loading errors are observed, and the device is otherwise functional
during normal operation.

This may indicate incomplete interrupt shutdown handling in the btintel_pcie
driver.