linux-stable.git/drivers/net/wireless/mediatek, branch v7.2.4 Linux kernel stable tree wifi: mt76: mt7996: validate default EEPROM firmware size 2026-09-07T15:37:27+00:00 Laxman Acharya Padhya acharyalaxman8848@gmail.com 2026-07-13T11:54:12+00:00 7074ec3769820302f1ccf8794a40a6582153b820 commit 653c6e289b13cc6942f3e8f8e3c568e70fa42d1f upstream. The default EEPROM firmware is parsed and copied as a full EEPROM without checking its length. A truncated file can make the driver read beyond the firmware buffer during variant validation or the fallback copy. Reject files shorter than MT7996_EEPROM_SIZE before parsing or copying the firmware. Fixes: 98686cd21624 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices") Cc: stable@vger.kernel.org Signed-off-by: Laxman Acharya Padhya <acharyalaxman8848@gmail.com> Link: https://patch.msgid.link/20260713115412.67095-1-acharyalaxman8848@gmail.com Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 653c6e289b13cc6942f3e8f8e3c568e70fa42d1f upstream.

The default EEPROM firmware is parsed and copied as a full EEPROM
without checking its length. A truncated file can make the driver
read beyond the firmware buffer during variant validation or the
fallback copy.

Reject files shorter than MT7996_EEPROM_SIZE before parsing or
copying the firmware.

Fixes: 98686cd21624 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices")
Cc: stable@vger.kernel.org
Signed-off-by: Laxman Acharya Padhya <acharyalaxman8848@gmail.com>
Link: https://patch.msgid.link/20260713115412.67095-1-acharyalaxman8848@gmail.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7996: fix TX DMA mapping leak for AddBA req frames 2026-09-07T15:37:26+00:00 Felix Fietkau nbd@nbd.name 2026-07-22T08:26:05+00:00 b754d3a6d44c53d9853eba374d8a7ef279a9d00a commit deaa2e3656937fbbe312f0ee2616c756c6e2511f upstream. mt7996/mt7992 hand the firmware a HW MAC-TXP for AddBA req action frames (MT_TXD7_MAC_TXD, set in mt7996_mac_write_txwi_80211()), but are otherwise FW-TXP devices. On tx free mt76_connac_txp_skb_unmap() therefore decodes the per-frame txp as a struct mt76_connac_fw_txp. For a MAC-TXP the fw_txp.nbuf byte aliases the AddBA TID word (MT_TXP1_TID_ADDBA), which is always zero, so the unmap loop runs zero times and the skb DMA mapping in buf[1] is never unmapped. buf[1].skip_unmap is set unconditionally, so the generic DMA-ring cleanup skips it as well. Each AddBA req therefore leaks one TX DMA mapping, roughly one per (re)association. With WED enabled these mappings are bounced through the WED swiotlb pool, so under continuous client reconnect churn the pool is exhausted after ~1-2 days, after which DMA mapping fails for WED, the WiFi MCU and other on-SoC consumers. Keep the deferred (token release) unmap that the design relies on, and add an mt7996-specific txp unmap that inspects MT_TXD7_MAC_TXD and unmaps buf[1] from the MAC-TXP layout for those frames, delegating to mt76_connac_txp_skb_unmap() otherwise. Cc: stable@vger.kernel.org Fixes: cb6ebbdffef2 ("wifi: mt76: mt7996: support writing MAC TXD for AddBA Request") Link: https://patch.msgid.link/20260722082610.2699628-13-nbd@nbd.name Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit deaa2e3656937fbbe312f0ee2616c756c6e2511f upstream.

mt7996/mt7992 hand the firmware a HW MAC-TXP for AddBA req action frames
(MT_TXD7_MAC_TXD, set in mt7996_mac_write_txwi_80211()), but are otherwise
FW-TXP devices. On tx free mt76_connac_txp_skb_unmap() therefore decodes
the per-frame txp as a struct mt76_connac_fw_txp. For a MAC-TXP the
fw_txp.nbuf byte aliases the AddBA TID word (MT_TXP1_TID_ADDBA), which is
always zero, so the unmap loop runs zero times and the skb DMA mapping in
buf[1] is never unmapped. buf[1].skip_unmap is set unconditionally, so the
generic DMA-ring cleanup skips it as well.

Each AddBA req therefore leaks one TX DMA mapping, roughly one per
(re)association. With WED enabled these mappings are bounced through the
WED swiotlb pool, so under continuous client reconnect churn the pool is
exhausted after ~1-2 days, after which DMA mapping fails for WED, the WiFi
MCU and other on-SoC consumers.

Keep the deferred (token release) unmap that the design relies on, and add
an mt7996-specific txp unmap that inspects MT_TXD7_MAC_TXD and unmaps
buf[1] from the MAC-TXP layout for those frames, delegating to
mt76_connac_txp_skb_unmap() otherwise.

Cc: stable@vger.kernel.org
Fixes: cb6ebbdffef2 ("wifi: mt76: mt7996: support writing MAC TXD for AddBA Request")
Link: https://patch.msgid.link/20260722082610.2699628-13-nbd@nbd.name
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7996: bound the device EEPROM address before the EFUSE copy 2026-09-07T15:37:26+00:00 Bryam Vargas hexlabsecurity@proton.me 2026-06-25T12:10:27+00:00 6be59da2063d5b3522bfde8aae0487ec095eb384 commit 13b3c29a782033ce4a230be9e5618032813dbcd4 upstream. mt7996_mcu_get_eeprom() derives the destination of the EFUSE/EXT block copy from the address reported by the MCU response (event->addr, a device-controlled __le32) and clamps only the copy length, never the destination offset into dev->mt76.eeprom.data. A malicious or malfunctioning device can report an arbitrary address and drive an out-of-bounds write of up to MT7996_EXT_EEPROM_BLOCK_SIZE bytes past eeprom.data. Reject a response whose address would place the copy outside eeprom.data before deriving the destination pointer. Devices that echo the requested in-bounds offset are unaffected. Fixes: 98686cd21624 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices") Cc: stable@vger.kernel.org Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me> Link: https://patch.msgid.link/20260625-b4-disp-16f99062-v1-2-aee52ecf61b9@proton.me Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 13b3c29a782033ce4a230be9e5618032813dbcd4 upstream.

mt7996_mcu_get_eeprom() derives the destination of the EFUSE/EXT block
copy from the address reported by the MCU response (event->addr, a
device-controlled __le32) and clamps only the copy length, never the
destination offset into dev->mt76.eeprom.data. A malicious or
malfunctioning device can report an arbitrary address and drive an
out-of-bounds write of up to MT7996_EXT_EEPROM_BLOCK_SIZE bytes past
eeprom.data.

Reject a response whose address would place the copy outside eeprom.data
before deriving the destination pointer. Devices that echo the requested
in-bounds offset are unaffected.

Fixes: 98686cd21624 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260625-b4-disp-16f99062-v1-2-aee52ecf61b9@proton.me
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7925: cancel mlo_pm_work on stop 2026-09-07T15:37:26+00:00 Devin Wittmayer lucid_duck@justthetip.ca 2026-06-27T20:29:46+00:00 9e20da749ad229a1aa649ece528721b9652f15e1 commit 81faf578320df2dfc682a96baa6e85851dd68b6f upstream. mt7925 queues mlo_pm_work with a 5 second delay during multi-link power-save setup and never cancels it on the stop path. If the device is torn down inside that window, the work outlives the teardown and its timer fires afterwards, trying to queue onto the workqueue that is already gone: workqueue: cannot queue mt7925_mlo_pm_work [mt7925_common] on wq phy0 WARNING: kernel/workqueue.c:2283 at __queue_work+0x59/0xa0, CPU#1: swapper/1/0 call_timer_fn+0x2a/0x140 __run_timers+0x203/0x330 run_timer_softirq+0x86/0xf0 mt7921 already has its own stop callback, so add one for mt7925 that cancels the work before calling mt792x_stop(). mt7925_ops backs both the PCIe and USB drivers, so this covers both. Fixes: 276a56883257 ("wifi: mt76: mt7925: update the power-saving flow") Cc: stable@vger.kernel.org Tested-by: Traockl <281473483+Traockl@users.noreply.github.com> Signed-off-by: Devin Wittmayer <lucid_duck@justthetip.ca> Link: https://patch.msgid.link/20260627202946.25598-1-lucid_duck@justthetip.ca Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 81faf578320df2dfc682a96baa6e85851dd68b6f upstream.

mt7925 queues mlo_pm_work with a 5 second delay during multi-link
power-save setup and never cancels it on the stop path. If the device is
torn down inside that window, the work outlives the teardown and its timer
fires afterwards, trying to queue onto the workqueue that is already gone:

  workqueue: cannot queue mt7925_mlo_pm_work [mt7925_common] on wq phy0
  WARNING: kernel/workqueue.c:2283 at __queue_work+0x59/0xa0, CPU#1: swapper/1/0
   call_timer_fn+0x2a/0x140
   __run_timers+0x203/0x330
   run_timer_softirq+0x86/0xf0

mt7921 already has its own stop callback, so add one for mt7925 that
cancels the work before calling mt792x_stop(). mt7925_ops backs both the
PCIe and USB drivers, so this covers both.

Fixes: 276a56883257 ("wifi: mt76: mt7925: update the power-saving flow")
Cc: stable@vger.kernel.org
Tested-by: Traockl <281473483+Traockl@users.noreply.github.com>
Signed-off-by: Devin Wittmayer <lucid_duck@justthetip.ca>
Link: https://patch.msgid.link/20260627202946.25598-1-lucid_duck@justthetip.ca
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7915: bound the device EEPROM address before the EFUSE copy 2026-09-07T15:37:26+00:00 Bryam Vargas hexlabsecurity@proton.me 2026-06-25T12:10:26+00:00 5f48b0d752a76590e2c613aae5345c2474627d1b commit 44b5adfe49499f53002737f5fe81d608c08122fc upstream. mt7915_mcu_get_eeprom() copies a fixed EFUSE block into the driver's dev->mt76.eeprom.data buffer at the offset reported by the MCU response (res->addr, a device-controlled __le32) without checking it against the buffer size. A malicious or malfunctioning device can report an arbitrary address and drive a 16-byte out-of-bounds write past eeprom.data. Reject a response whose address would place the copy outside eeprom.data before deriving the destination pointer. Devices that echo the requested in-bounds offset are unaffected. Fixes: e57b7901469f ("mt76: add mac80211 driver for MT7915 PCIe-based chipsets") Cc: stable@vger.kernel.org Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me> Link: https://patch.msgid.link/20260625-b4-disp-16f99062-v1-1-aee52ecf61b9@proton.me Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 44b5adfe49499f53002737f5fe81d608c08122fc upstream.

mt7915_mcu_get_eeprom() copies a fixed EFUSE block into the driver's
dev->mt76.eeprom.data buffer at the offset reported by the MCU response
(res->addr, a device-controlled __le32) without checking it against the
buffer size. A malicious or malfunctioning device can report an arbitrary
address and drive a 16-byte out-of-bounds write past eeprom.data.

Reject a response whose address would place the copy outside eeprom.data
before deriving the destination pointer. Devices that echo the requested
in-bounds offset are unaffected.

Fixes: e57b7901469f ("mt76: add mac80211 driver for MT7915 PCIe-based chipsets")
Cc: stable@vger.kernel.org
Signed-off-by: Bryam Vargas <hexlabsecurity@proton.me>
Link: https://patch.msgid.link/20260625-b4-disp-16f99062-v1-1-aee52ecf61b9@proton.me
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7615: avoid waiting for mac work under the mt76 mutex 2026-09-07T15:37:26+00:00 Runyu Xiao runyu.xiao@seu.edu.cn 2026-06-12T04:13:31+00:00 44be85af3e1772ffb3332feafedad2a73b22854c commit bda8324270b1ac91bfba1df8928e0570e29759e8 upstream. mt7615_suspend() acquired the mt76 mutex and then called cancel_delayed_work_sync() on mac_work. mt7615_mac_work() acquires the same mutex via mt7615_mutex_acquire() at the top of the worker, so if mac_work is already running and blocked on the mutex, the suspend path deadlocks waiting for the work it holds the mutex against. Flush scan_work and mac_work before taking the mutex, matching the suspend paths in mt7921 and mt7925. scan_work only takes the mt76 spinlock, but moving it keeps the sequence consistent. This also keeps mac_work from running over an already suspended HIF, which the previous split (async cancel under the lock, sync cancel after release) would have allowed. Fixes: c6bf20109a3f ("mt76: mt7615: add WoW support") Cc: stable@vger.kernel.org Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn> Link: https://patch.msgid.link/20260612041331.2596331-1-runyu.xiao@seu.edu.cn Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit bda8324270b1ac91bfba1df8928e0570e29759e8 upstream.

mt7615_suspend() acquired the mt76 mutex and then called
cancel_delayed_work_sync() on mac_work.  mt7615_mac_work() acquires the
same mutex via mt7615_mutex_acquire() at the top of the worker, so if
mac_work is already running and blocked on the mutex, the suspend path
deadlocks waiting for the work it holds the mutex against.

Flush scan_work and mac_work before taking the mutex, matching the
suspend paths in mt7921 and mt7925.  scan_work only takes the mt76
spinlock, but moving it keeps the sequence consistent.  This also keeps
mac_work from running over an already suspended HIF, which the previous
split (async cancel under the lock, sync cancel after release) would
have allowed.

Fixes: c6bf20109a3f ("mt76: mt7615: add WoW support")
Cc: stable@vger.kernel.org
Signed-off-by: Runyu Xiao <runyu.xiao@seu.edu.cn>
Link: https://patch.msgid.link/20260612041331.2596331-1-runyu.xiao@seu.edu.cn
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7925: cancel pending mlo_pm_work 2026-09-07T15:37:02+00:00 Wentao Guan guanwentao@uniontech.com 2026-06-30T09:02:18+00:00 c5e073f2fbfd34d22099a50d96f60990799753e2 commit 2889e84282dda147f10b10d94cf0efd90a349c53 upstream. If the device is reset, suspended or unregistered within that window, the pending work can still run and access vif/bss data that may already be freed, or send MCU commands while the firmware is not available. Add cancel_delayed_work_sync(&dev->mlo_pm_work) in all relevant teardown and suspend paths: - mt7925_mac_reset_work() (chip reset recovery) - mt7925e_unregister_device() (PCIe unbind) - mt7925_pci_suspend() (PCIe bus suspend) - mt7925_suspend() (mac80211 suspend) - mt7925u_suspend() (USB bus / runtime suspend) This ensures the work is stopped before the device state becomes invalid. Assisted-by: kimi-cli:kimi-k2.7 code Assisted-by: atomcode:glm-5.2 #Reported-by Fixes: 276a568832577 ("wifi: mt76: mt7925: update the power-saving flow") Cc: stable@vger.kernel.org Signed-off-by: Wentao Guan <guanwentao@uniontech.com> Link: https://patch.msgid.link/20260630090218.3202029-1-guanwentao@uniontech.com Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 2889e84282dda147f10b10d94cf0efd90a349c53 upstream.

If the device is reset, suspended or unregistered within that window,
the pending work can still run and access vif/bss data that may already
be freed, or send MCU commands while the firmware is not available.

Add cancel_delayed_work_sync(&dev->mlo_pm_work) in all relevant teardown
and suspend paths:

 - mt7925_mac_reset_work()        (chip reset recovery)
 - mt7925e_unregister_device()    (PCIe unbind)
 - mt7925_pci_suspend()           (PCIe bus suspend)
 - mt7925_suspend()               (mac80211 suspend)
 - mt7925u_suspend()              (USB bus / runtime suspend)

This ensures the work is stopped before the device state becomes
invalid.

Assisted-by: kimi-cli:kimi-k2.7 code
Assisted-by: atomcode:glm-5.2 #Reported-by

Fixes: 276a568832577 ("wifi: mt76: mt7925: update the power-saving flow")
Cc: stable@vger.kernel.org
Signed-off-by: Wentao Guan <guanwentao@uniontech.com>
Link: https://patch.msgid.link/20260630090218.3202029-1-guanwentao@uniontech.com
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb 2026-09-02T12:33:21+00:00 Devin Wittmayer lucid_duck@justthetip.ca 2026-07-15T02:33:48+00:00 e5e8fc11a7ac578f16079f855b7fffc1649d053c commit ef3e34874d2332d0f63e72c2c35ce5c93568c125 upstream. mt7925_usb_sdio_tx_prepare_skb() pushes a TX descriptor and a USB header onto every skb and assumes the headroom for them is already there. That holds for locally generated traffic, where mac80211 reserves hw->extra_tx_headroom, but forwarded frames are sent through ieee80211_8023_xmit(), which does not reserve it. Bridge a wired interface to an mt7925u AP and the first forwarded frame that arrives short panics the kernel: skbuff: skb_under_panic: len:415 put:4 tail:0x19b end:0x640 dev:wlan1 kernel BUG at net/core/skbuff.c:212! Call trace: skb_panic+0x58/0x60 (P) skb_push+0x58/0x60 mt7925_usb_sdio_tx_prepare_skb+0xf8/0x1b8 [mt7925_common] mt76u_tx_queue_skb+0xa0/0x1f8 [mt76_usb] __mt76_tx_queue_skb+0x54/0xe8 [mt76] mt76_txq_schedule.part.0+0x204/0x478 [mt76] mt76_txq_schedule_all+0x50/0x80 [mt76] mt792x_tx_worker+0x68/0x100 [mt792x_lib] __mt76_worker_fn+0x84/0x150 [mt76] Whether a given setup hits it depends on how much headroom the ingress netdev leaves in its rx skbs. Reproduced on a Raspberry Pi 5 bridging onboard ethernet to a Netgear A9000; originally reported on an MT7986 router running OpenWrt. Nick Morrow's testing on a Pi 4 (bcmgenet), which leaves more headroom, helped narrow the trigger to the ingress path. The same bug was fixed on mt7921 by commit 98c4d0abf5c4 ("mt76: mt7921: don't assume adequate headroom for SDIO headers"), but mt7925 was copied from mt7921 without the fix. Add the same guard here. Fixes: c948b5da6bbe ("wifi: mt76: mt7925: add Mediatek Wi-Fi7 driver for mt7925 chips") Cc: stable@vger.kernel.org Link: https://github.com/morrownr/mt76/issues/52 Signed-off-by: Devin Wittmayer <lucid_duck@justthetip.ca> Link: https://patch.msgid.link/20260715023348.59506-1-lucid_duck@justthetip.ca Signed-off-by: Felix Fietkau <nbd@nbd.name> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit ef3e34874d2332d0f63e72c2c35ce5c93568c125 upstream.

mt7925_usb_sdio_tx_prepare_skb() pushes a TX descriptor and a USB
header onto every skb and assumes the headroom for them is already
there. That holds for locally generated traffic, where mac80211
reserves hw->extra_tx_headroom, but forwarded frames are sent through
ieee80211_8023_xmit(), which does not reserve it. Bridge a wired
interface to an mt7925u AP and the first forwarded frame that arrives
short panics the kernel:

 skbuff: skb_under_panic: len:415 put:4 tail:0x19b end:0x640 dev:wlan1
 kernel BUG at net/core/skbuff.c:212!
 Call trace:
  skb_panic+0x58/0x60 (P)
  skb_push+0x58/0x60
  mt7925_usb_sdio_tx_prepare_skb+0xf8/0x1b8 [mt7925_common]
  mt76u_tx_queue_skb+0xa0/0x1f8 [mt76_usb]
  __mt76_tx_queue_skb+0x54/0xe8 [mt76]
  mt76_txq_schedule.part.0+0x204/0x478 [mt76]
  mt76_txq_schedule_all+0x50/0x80 [mt76]
  mt792x_tx_worker+0x68/0x100 [mt792x_lib]
  __mt76_worker_fn+0x84/0x150 [mt76]

Whether a given setup hits it depends on how much headroom the ingress
netdev leaves in its rx skbs. Reproduced on a Raspberry Pi 5 bridging
onboard ethernet to a Netgear A9000; originally reported on an MT7986
router running OpenWrt. Nick Morrow's testing on a Pi 4 (bcmgenet),
which leaves more headroom, helped narrow the trigger to the ingress
path.

The same bug was fixed on mt7921 by commit 98c4d0abf5c4 ("mt76:
mt7921: don't assume adequate headroom for SDIO headers"), but mt7925
was copied from mt7921 without the fix. Add the same guard here.

Fixes: c948b5da6bbe ("wifi: mt76: mt7925: add Mediatek Wi-Fi7 driver for mt7925 chips")
Cc: stable@vger.kernel.org
Link: https://github.com/morrownr/mt76/issues/52
Signed-off-by: Devin Wittmayer <lucid_duck@justthetip.ca>
Link: https://patch.msgid.link/20260715023348.59506-1-lucid_duck@justthetip.ca
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
wifi: mt76: mt7921: refactor regd update to fix recursive mutex deadlock 2026-08-16T18:07:18+00:00 Charlie-cy Wu charlie-cy.wu@mediatek.corp-partner.google.com 2026-06-29T08:35:43+00:00 d6e7d57ed967def9c964a58328ffba409f7efb64 Split mt7921_mcu_regd_update() into two functions to prevent recursive mutex acquisition. Introduce __mt7921_mcu_regd_update() as the internal implementation that assumes the mutex is already held by the caller, while mt7921_mcu_regd_update() remains as the external interface that handles mutex acquisition and release. This fixes a deadlock issue when mt7921_regd_set_6ghz_power_type() is called with the device mutex already held. Without this change, calling mt7921_mcu_regd_update() would attempt to acquire the same mutex again, causing a recursive lock deadlock. The __mt7921_mcu_regd_update() function can be safely called when the caller has already acquired the device mutex, avoiding the deadlock while maintaining proper synchronization for regulatory domain updates. Fixes: dc2608cf5224 ("wifi: mt76: mt7921: refactor regulatory notifier flow") Signed-off-by: Charlie-cy Wu <Charlie-cy.Wu@mediatek.com> Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com> Tested-by: Devin Wittmayer <lucid_duck@justthetip.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
Split mt7921_mcu_regd_update() into two functions to prevent recursive
mutex acquisition. Introduce __mt7921_mcu_regd_update() as the internal
implementation that assumes the mutex is already held by the caller,
while mt7921_mcu_regd_update() remains as the external interface that
handles mutex acquisition and release.

This fixes a deadlock issue when mt7921_regd_set_6ghz_power_type() is
called with the device mutex already held. Without this change, calling
mt7921_mcu_regd_update() would attempt to acquire the same mutex again,
causing a recursive lock deadlock.

The __mt7921_mcu_regd_update() function can be safely called when the
caller has already acquired the device mutex, avoiding the deadlock
while maintaining proper synchronization for regulatory domain updates.

Fixes: dc2608cf5224 ("wifi: mt76: mt7921: refactor regulatory notifier flow")
Signed-off-by: Charlie-cy Wu <Charlie-cy.Wu@mediatek.com>
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Tested-by: Devin Wittmayer <lucid_duck@justthetip.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Revert "wifi: mt76: Disable napi when removing device" 2026-08-13T16:00:55+00:00 Mikhail Gavrilov mikhail.v.gavrilov@gmail.com 2026-08-04T12:00:04+00:00 3aa1dcaa4f6f5ae08936491e08bd456f331f2d40 This reverts commit 13b7e6a96a005c656d38f3da51581deaf9866375. 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: 13b7e6a96a00 ("wifi: mt76: Disable napi when removing device") Tested-by: Devin Wittmayer <lucid_duck@justthetip.ca> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> 
This reverts commit 13b7e6a96a005c656d38f3da51581deaf9866375.

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: 13b7e6a96a00 ("wifi: mt76: Disable napi when removing device")
Tested-by: Devin Wittmayer <lucid_duck@justthetip.ca>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>