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This reverts commit13b7e6a96a. That commit made mt76_dma_cleanup() disable every RX NAPI instance before deleting it, to silence WARNs in __netif_napi_del_locked() and page_pool_disable_direct_recycling() seen when unloading mt7915e with an MT7916. On mt7921e and mt7925e the same instances are already disabled earlier, in mt7921e_unregister_device() and mt7925e_unregister_device(), which only afterwards call mt792x_dma_cleanup() -> mt76_dma_cleanup(). Each instance is therefore disabled twice, and napi_disable() is not idempotent: on return it leaves NAPIF_STATE_SCHED and NAPIF_STATE_NPSVC set, so the second call spins in usleep_range() forever, waiting for bits that nobody will clear. mt7921_pci_shutdown() and mt7925_pci_shutdown() reuse the remove path, so this is hit on every reboot, poweroff and module unload. It is silent: the stuck task keeps sleeping and rescheduling, so neither the hung task detector nor the lockup detectors fire, and the last line on the console is "systemd-shutdown[1]: Rebooting." task:modprobe state:D stack:25720 pid:7954 tgid:7954 Call Trace: <TASK> __schedule+0x11b8/0x26d0 schedule+0xe7/0x2f0 schedule_hrtimeout_range_clock+0x218/0x330 usleep_range_state+0x133/0x1b0 napi_disable_locked+0x37d/0x5f0 napi_disable+0x43/0x80 mt76_dma_cleanup+0x2b4/0x860 [mt76] mt7921_pci_remove+0x17f/0x350 [mt7921e] pci_device_remove+0xb6/0x1e0 device_release_driver_internal+0x38d/0x540 driver_detach+0xd0/0x1b0 bus_remove_driver+0x127/0x2d0 pci_unregister_driver+0x2a/0x280 __do_sys_delete_module+0x36a/0x5b0 do_syscall_64+0x11c/0x6d0 entry_SYSCALL_64_after_hwframe+0x76/0x7e </TASK> Dropping the two driver-side loops instead was tried and rejected: with them gone, the RX poll can reach mt76_token_release() via PKT_TYPE_TXRX_NOTIFY and mt7921_mac_tx_free() while mt76_connac2_tx_token_put() is running idr_destroy(&dev->token) outside token_lock, which is a use-after-free rather than a hang [1]. Revert for now, so that reboot, poweroff and module unload work again. The WARNs on mt7915e are a less severe problem than an unbootable machine, and fixing them belongs in the drivers that delete the NAPI instances, where each one can pick a point that is safe for its own teardown order, rather than in the shared mt76_dma_cleanup(). [ This is the "landing soonish" known regression fix mentioned in the previous networking merge commit - Linus ] Reported-by: Bert Karwatzki <spasswolf@web.de> Closes: https://lore.kernel.org/all/20260724151419.26014-1-spasswolf@web.de/ Closes: https://bugzilla.kernel.org/show_bug.cgi?id=221818 Link: https://lore.kernel.org/all/20260730050428.GA73812@sol/ [1] Signed-off-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Acked-by: Nicolas Cavallari <nicolas.cavallari@green-communications.fr> Fixes:13b7e6a96a("wifi: mt76: Disable napi when removing device") Tested-by: Devin Wittmayer <lucid_duck@justthetip.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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