Files
mt76/mt7925
JB TsaiandFelix Fietkau 98c13eb564 wifi: mt76: mt7925: Fix unregister deadlock
During device shutdown or removal, a deadlock can occur between the
PCIe remove path and the driver's asynchronous reset work.

The unregistration path calls napi_disable() before cancelling the
reset work. If the reset work runs concurrently, it may re-enable NAPI
and schedule it. Because the device is being unregistered, this can
lead to NAPI state corruption where NAPI is marked as scheduled but
never polled, causing subsequent napi_disable() calls to hang forever.

Fix this by:
1. Moving cancel_work_sync(&dev->reset_work) to the very start of
   mt7925e_unregister_device(), ensuring it is stopped before NAPI
   is disabled.
2. Setting the MT76_REMOVED flag early in the PCI remove path to
   prevent new reset work from being queued.
3. Checking MT76_REMOVED in mt7925_mac_reset_work() and aborting the
   reset early if the device is being removed.

Co-developed-by: Fei Shao <[email protected]>
Signed-off-by: JB Tsai <[email protected]>
Tested-by: Rafael Passos <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Felix Fietkau <[email protected]>
2026-07-21 15:34:22 +02:00
..