commit 78ab4be549 upstream.
A warning on driver removal started occurring after commit 9dd05df840
("net: warn if NAPI instance wasn't shut down"). Disable tx napi before
deleting it in mt76_dma_cleanup().
WARNING: CPU: 4 PID: 18828 at net/core/dev.c:7288 __netif_napi_del_locked+0xf0/0x100
CPU: 4 UID: 0 PID: 18828 Comm: modprobe Not tainted 6.15.0-rc4 #4 PREEMPT(lazy)
Hardware name: ASUS System Product Name/PRIME X670E-PRO WIFI, BIOS 3035 09/05/2024
RIP: 0010:__netif_napi_del_locked+0xf0/0x100
Call Trace:
<TASK>
mt76_dma_cleanup+0x54/0x2f0 [mt76]
mt7921_pci_remove+0xd5/0x190 [mt7921e]
pci_device_remove+0x47/0xc0
device_release_driver_internal+0x19e/0x200
driver_detach+0x48/0x90
bus_remove_driver+0x6d/0xf0
pci_unregister_driver+0x2e/0xb0
__do_sys_delete_module.isra.0+0x197/0x2e0
do_syscall_64+0x7b/0x160
entry_SYSCALL_64_after_hwframe+0x76/0x7e
Tested with mt7921e but the same pattern can be actually applied to other
mt76 drivers calling mt76_dma_cleanup() during removal. Tx napi is enabled
in their *_dma_init() functions and only toggled off and on again inside
their suspend/resume/reset paths. So it should be okay to disable tx
napi in such a generic way.
Found by Linux Verification Center (linuxtesting.org).
Fixes: 2ac515a5d7 ("mt76: mt76x02: use napi polling for tx cleanup")
Cc: stable@vger.kernel.org
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Tested-by: Ming Yen Hsieh <mingyen.hsieh@mediatek.com>
Link: https://patch.msgid.link/20250506115540.19045-1-pchelkin@ispras.ru
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5e700b06b9