wifi: mt76: mt7925: Fix unregister deadlock

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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 <fshao@google.com>
Signed-off-by: JB Tsai <jb.tsai@mediatek.com>
Tested-by: Rafael Passos <rafael@rcpassos.me>
Link: https://patch.msgid.link/20260630090610.586954-1-jb.tsai@mediatek.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>

...

This commit is contained in:

JB Tsai 2026-06-30 17:06:10 +08:00 • committed by Felix Fietkau

parent ef3e34874d

commit eb628006a2

2 changed files with 9 additions and 2 deletions

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7

drivers/net/wireless/mediatek/mt76/mt7925/mac.c

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4

drivers/net/wireless/mediatek/mt76/mt7925/pci.c

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