From nobody Sat Oct 4 03:17:25 2025 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id C52A321FF24; Wed, 20 Aug 2025 14:14:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=83.149.199.84 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755699304; cv=none; b=SUT/537h6YknHPlLzKiLdz8vYr4TvDyOE4099al8a2Nvp5DFl3vhi7/Q7pGa6qRrUgOBJd/v9VKD+wE2UdyltMd0u/c4ZVa+TcDNTc9dIA+zfmf8B+q9bWAQ5fucLBWbVeWec5Bvq79sWpQeuuQ35EZHx5X6ZFsFVXdVqH1LFQ0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755699304; c=relaxed/simple; bh=gtU6zVpCfLilqmweYMJWBdWiyEXgPx2YbOTShozMP1Y=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=YhuAurFpPHnPEuP2aEfJWYd2Pzy1A8o2HpfbT4FdZotb9FXJ0tOTriOOTzQYgHxgpvPdW+nlYP6FR90AFK7/ThOtVuOWUCwHHmooM5Mg0gxzD/GYhVB9tG90gxtQoN96U7gl1wK4nR/CImuKoba0Vr9mTgYaiPldllaMzvDEKTQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ispras.ru; spf=pass smtp.mailfrom=ispras.ru; dkim=pass (1024-bit key) header.d=ispras.ru header.i=@ispras.ru header.b=m1oUMek9; arc=none smtp.client-ip=83.149.199.84 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ispras.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ispras.ru Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ispras.ru header.i=@ispras.ru header.b="m1oUMek9" Received: from debian.intra.ispras.ru (unknown [10.10.165.10]) by mail.ispras.ru (Postfix) with ESMTPSA id 9BCBE4028387; Wed, 20 Aug 2025 14:14:56 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 mail.ispras.ru 9BCBE4028387 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1755699296; bh=5JjmZf15UhpzUiI7r1soRuB11AzCTswYFwRBjFzcgeM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m1oUMek9RNDsIJ4HeXGz/o150u0WEeSk6ETi9tKsXmkmg4D3BzO8GtmvmPynYDjyD BcxNaHcnmqI93nFr2Al7k3UnGgIYFEwNf/m1sFUkP89TaaspUmjMkVnMukio6mwWdr cm/syvM5cXFHDDCK9MQPmg/AG9JaSbNor6o7oAJQ= From: Fedor Pchelkin To: Ping-Ke Shih Cc: Fedor Pchelkin , Zong-Zhe Yang , Po-Hao Huang , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org, stable@vger.kernel.org Subject: [PATCH rtw-next 1/2] wifi: rtw89: fix use-after-free in rtw89_core_tx_kick_off_and_wait() Date: Wed, 20 Aug 2025 17:13:45 +0300 Message-ID: <20250820141441.106156-2-pchelkin@ispras.ru> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250820141441.106156-1-pchelkin@ispras.ru> References: <20250820141441.106156-1-pchelkin@ispras.ru> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" There is a bug observed when rtw89_core_tx_kick_off_and_wait() tries to access already freed skb_data: BUG: KFENCE: use-after-free write in rtw89_core_tx_kick_off_and_wait drive= rs/net/wireless/realtek/rtw89/core.c:1110 CPU: 6 UID: 0 PID: 41377 Comm: kworker/u64:24 Not tainted 6.17.0-rc1+ #1 = PREEMPT(lazy) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS edk2-20250523-= 14.fc42 05/23/2025 Workqueue: events_unbound cfg80211_wiphy_work [cfg80211] Use-after-free write at 0x0000000020309d9d (in kfence-#251): rtw89_core_tx_kick_off_and_wait drivers/net/wireless/realtek/rtw89/core.c:= 1110 rtw89_core_scan_complete drivers/net/wireless/realtek/rtw89/core.c:5338 rtw89_hw_scan_complete_cb drivers/net/wireless/realtek/rtw89/fw.c:7979 rtw89_chanctx_proceed_cb drivers/net/wireless/realtek/rtw89/chan.c:3165 rtw89_chanctx_proceed drivers/net/wireless/realtek/rtw89/chan.h:141 rtw89_hw_scan_complete drivers/net/wireless/realtek/rtw89/fw.c:8012 rtw89_mac_c2h_scanofld_rsp drivers/net/wireless/realtek/rtw89/mac.c:5059 rtw89_fw_c2h_work drivers/net/wireless/realtek/rtw89/fw.c:6758 process_one_work kernel/workqueue.c:3241 worker_thread kernel/workqueue.c:3400 kthread kernel/kthread.c:463 ret_from_fork arch/x86/kernel/process.c:154 ret_from_fork_asm arch/x86/entry/entry_64.S:258 kfence-#251: 0x0000000056e2393d-0x000000009943cb62, size=3D232, cache=3Dsk= buff_head_cache allocated by task 41377 on cpu 6 at 77869.159548s (0.009551s ago): __alloc_skb net/core/skbuff.c:659 __netdev_alloc_skb net/core/skbuff.c:734 ieee80211_nullfunc_get net/mac80211/tx.c:5844 rtw89_core_send_nullfunc drivers/net/wireless/realtek/rtw89/core.c:3431 rtw89_core_scan_complete drivers/net/wireless/realtek/rtw89/core.c:5338 rtw89_hw_scan_complete_cb drivers/net/wireless/realtek/rtw89/fw.c:7979 rtw89_chanctx_proceed_cb drivers/net/wireless/realtek/rtw89/chan.c:3165 rtw89_chanctx_proceed drivers/net/wireless/realtek/rtw89/chan.c:3194 rtw89_hw_scan_complete drivers/net/wireless/realtek/rtw89/fw.c:8012 rtw89_mac_c2h_scanofld_rsp drivers/net/wireless/realtek/rtw89/mac.c:5059 rtw89_fw_c2h_work drivers/net/wireless/realtek/rtw89/fw.c:6758 process_one_work kernel/workqueue.c:3241 worker_thread kernel/workqueue.c:3400 kthread kernel/kthread.c:463 ret_from_fork arch/x86/kernel/process.c:154 ret_from_fork_asm arch/x86/entry/entry_64.S:258 freed by task 1045 on cpu 9 at 77869.168393s (0.001557s ago): ieee80211_tx_status_skb net/mac80211/status.c:1117 rtw89_pci_release_txwd_skb drivers/net/wireless/realtek/rtw89/pci.c:564 rtw89_pci_release_tx_skbs.isra.0 drivers/net/wireless/realtek/rtw89/pci.c:= 651 rtw89_pci_release_tx drivers/net/wireless/realtek/rtw89/pci.c:676 rtw89_pci_napi_poll drivers/net/wireless/realtek/rtw89/pci.c:4238 __napi_poll net/core/dev.c:7495 net_rx_action net/core/dev.c:7557 net/core/dev.c:7684 handle_softirqs kernel/softirq.c:580 do_softirq.part.0 kernel/softirq.c:480 __local_bh_enable_ip kernel/softirq.c:407 rtw89_pci_interrupt_threadfn drivers/net/wireless/realtek/rtw89/pci.c:927 irq_thread_fn kernel/irq/manage.c:1133 irq_thread kernel/irq/manage.c:1257 kthread kernel/kthread.c:463 ret_from_fork arch/x86/kernel/process.c:154 ret_from_fork_asm arch/x86/entry/entry_64.S:258 It is a consequence of a race between the waiting and the signalling side of the completion: Thread 1 Thread 2 rtw89_core_tx_kick_off_and_wait() rcu_assign_pointer(skb_data->wait, wait) /* start waiting */ wait_for_completion_timeout() rtw89_pci_tx_status() rtw89_core_tx_wait_comple= te() rcu_read_lock() /* signals completion a= nd * proceeds further */ complete(&wait->complet= ion) rcu_read_unlock() ... /* frees skb_data */ ieee80211_tx_status_ni() /* returns (exit status doesn't matter) */ wait_for_completion_timeout() ... /* accesses the already freed skb_data */ rcu_assign_pointer(skb_data->wait, NULL) The signalling side might proceed and free the underlying skb even before the waiting side is fully awoken and run to execution. RCU synchronization here would work well if the signalling side didn't go on and release skb on its own. Thus the waiting side should be told somehow about what is happening on the completion side. It seems the only correct way is to use standard locking primitives with owner tracking, like was originally published in one [1] of the versions of the patch mentioned in Fixes. [1]: https://lore.kernel.org/linux-wireless/20230404025259.15503-3-pkshih@r= ealtek.com/ Found by Linux Verification Center (linuxtesting.org). Fixes: 1ae5ca615285 ("wifi: rtw89: add function to wait for completion of T= X skbs") Cc: stable@vger.kernel.org Signed-off-by: Fedor Pchelkin --- The bug is tricky because the waiter-completer interaction isn't simple here. I've tried to come up with something that wouldn't require taking additional locks at rtw89_core_tx_wait_complete() but these ideas don't eliminate the possible race entirely, to my mind. Though one solution that _works_ currently is to get rid of 'struct rtw89_tx_wait_info' and replace it with the only field it is used for - 'bool tx_done'. Then it can be stored at 'struct ieee80211_tx_info::status::status_driver_data' directly without the need for allocating an extra dynamic object and tracking its lifecycle. I didn't post this since then the structure won't be expandable for new fields and that's probably the reason for why it wasn't done in this manner initially. drivers/net/wireless/realtek/rtw89/core.c | 15 ++++++++--- drivers/net/wireless/realtek/rtw89/core.h | 32 ++++++++++++++--------- drivers/net/wireless/realtek/rtw89/pci.c | 6 +++-- 3 files changed, 36 insertions(+), 17 deletions(-) diff --git a/drivers/net/wireless/realtek/rtw89/core.c b/drivers/net/wirele= ss/realtek/rtw89/core.c index 57590f5577a3..826540319027 100644 --- a/drivers/net/wireless/realtek/rtw89/core.c +++ b/drivers/net/wireless/realtek/rtw89/core.c @@ -1088,6 +1088,7 @@ int rtw89_core_tx_kick_off_and_wait(struct rtw89_dev = *rtwdev, struct sk_buff *sk struct rtw89_tx_skb_data *skb_data =3D RTW89_TX_SKB_CB(skb); struct rtw89_tx_wait_info *wait; unsigned long time_left; + bool free_wait =3D true; int ret =3D 0; =20 wait =3D kzalloc(sizeof(*wait), GFP_KERNEL); @@ -1097,7 +1098,8 @@ int rtw89_core_tx_kick_off_and_wait(struct rtw89_dev = *rtwdev, struct sk_buff *sk } =20 init_completion(&wait->completion); - rcu_assign_pointer(skb_data->wait, wait); + spin_lock_init(&wait->owner_lock); + skb_data->wait =3D wait; =20 rtw89_core_tx_kick_off(rtwdev, qsel); time_left =3D wait_for_completion_timeout(&wait->completion, @@ -1107,8 +1109,15 @@ int rtw89_core_tx_kick_off_and_wait(struct rtw89_dev= *rtwdev, struct sk_buff *sk else if (!wait->tx_done) ret =3D -EAGAIN; =20 - rcu_assign_pointer(skb_data->wait, NULL); - kfree_rcu(wait, rcu_head); + spin_lock_bh(&wait->owner_lock); + if (time_left =3D=3D 0 && wait->owner !=3D RTW89_TX_WAIT_OWNER_WAIT) { + free_wait =3D false; + wait->owner =3D RTW89_TX_WAIT_OWNER_COMPLETE; + } + spin_unlock_bh(&wait->owner_lock); + + if (free_wait) + kfree(wait); =20 return ret; } diff --git a/drivers/net/wireless/realtek/rtw89/core.h b/drivers/net/wirele= ss/realtek/rtw89/core.h index 43e10278e14d..0117f24324d5 100644 --- a/drivers/net/wireless/realtek/rtw89/core.h +++ b/drivers/net/wireless/realtek/rtw89/core.h @@ -3506,14 +3506,21 @@ struct rtw89_phy_rate_pattern { bool enable; }; =20 +enum rtw89_tx_wait_owner { + RTW89_TX_WAIT_OWNER_UNDET, + RTW89_TX_WAIT_OWNER_WAIT, + RTW89_TX_WAIT_OWNER_COMPLETE, +}; + struct rtw89_tx_wait_info { - struct rcu_head rcu_head; struct completion completion; bool tx_done; + spinlock_t owner_lock; /* lock to access owner */ + enum rtw89_tx_wait_owner owner; }; =20 struct rtw89_tx_skb_data { - struct rtw89_tx_wait_info __rcu *wait; + struct rtw89_tx_wait_info *wait; u8 hci_priv[]; }; =20 @@ -7259,22 +7266,23 @@ static inline struct sk_buff *rtw89_alloc_skb_for_r= x(struct rtw89_dev *rtwdev, } =20 static inline void rtw89_core_tx_wait_complete(struct rtw89_dev *rtwdev, - struct rtw89_tx_skb_data *skb_data, + struct rtw89_tx_wait_info *wait, bool tx_done) { - struct rtw89_tx_wait_info *wait; - - rcu_read_lock(); - - wait =3D rcu_dereference(skb_data->wait); - if (!wait) - goto out; + bool free_wait =3D true; =20 wait->tx_done =3D tx_done; + + spin_lock_bh(&wait->owner_lock); complete(&wait->completion); + if (wait->owner !=3D RTW89_TX_WAIT_OWNER_COMPLETE) { + free_wait =3D false; + wait->owner =3D RTW89_TX_WAIT_OWNER_WAIT; + } + spin_unlock_bh(&wait->owner_lock); =20 -out: - rcu_read_unlock(); + if (free_wait) + kfree(wait); } =20 static inline bool rtw89_is_mlo_1_1(struct rtw89_dev *rtwdev) diff --git a/drivers/net/wireless/realtek/rtw89/pci.c b/drivers/net/wireles= s/realtek/rtw89/pci.c index a669f2f843aa..d9d4558b21ea 100644 --- a/drivers/net/wireless/realtek/rtw89/pci.c +++ b/drivers/net/wireless/realtek/rtw89/pci.c @@ -462,9 +462,11 @@ static void rtw89_pci_tx_status(struct rtw89_dev *rtwd= ev, struct sk_buff *skb, u8 tx_status) { struct rtw89_tx_skb_data *skb_data =3D RTW89_TX_SKB_CB(skb); + struct rtw89_tx_wait_info *wait =3D skb_data->wait; struct ieee80211_tx_info *info; =20 - rtw89_core_tx_wait_complete(rtwdev, skb_data, tx_status =3D=3D RTW89_TX_D= ONE); + if (wait) + rtw89_core_tx_wait_complete(rtwdev, wait, tx_status =3D=3D RTW89_TX_DONE= ); =20 info =3D IEEE80211_SKB_CB(skb); ieee80211_tx_info_clear_status(info); @@ -1387,7 +1389,7 @@ static int rtw89_pci_txwd_submit(struct rtw89_dev *rt= wdev, } =20 tx_data->dma =3D dma; - rcu_assign_pointer(skb_data->wait, NULL); + skb_data->wait =3D NULL; =20 txwp_len =3D sizeof(*txwp_info); txwd_len =3D chip->txwd_body_size; --=20 2.50.1 From nobody Sat Oct 4 03:17:25 2025 Received: from mail.ispras.ru (mail.ispras.ru [83.149.199.84]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 56E5526A08C; Wed, 20 Aug 2025 14:15:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=83.149.199.84 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755699305; cv=none; b=XSMa24wanumft7R3MAXWV94CMsZsfJUruuiwlURIOorh+Bm4ck88rJyvV3GJSzDmF/Gr0FeM5pfItWqP4JwqNEDTovxO2KOW9UybwUQWts6B4/RUhUUCGKAZLWJfWyObItMJP3x2/malppHYFpjf6Xasg708CGYF5l+PEwDh/nc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755699305; c=relaxed/simple; bh=fcI+JfmbgazG0oyqr4vweApC/K8v8S2/HW2JZ5hXRzg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; 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a=rsa-sha256; c=relaxed/relaxed; d=ispras.ru; s=default; t=1755699297; bh=wbDVHY/uG91W3ht0vZ0TgeD7aGjlU9KbGb6El0uCnDU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ww1eVBRqAwLgd6RAOcTDxSB3ndfDykgKZOhpou8GxgKSVaBwK78SelmqPBFSE3nrz 4Q7GqdPLMQSE02xaEyrP5hS9gIxPsNS1pa8qDo+i9M35ek8ZCZI48dIEPaTMXgEtLQ mez2/oOpC5RO62aiMCHwm9J6N3FFtFNEiN4HKkM8= From: Fedor Pchelkin To: Ping-Ke Shih Cc: Fedor Pchelkin , Zong-Zhe Yang , Po-Hao Huang , linux-wireless@vger.kernel.org, linux-kernel@vger.kernel.org, lvc-project@linuxtesting.org Subject: [PATCH rtw-next 2/2] wifi: rtw89: avoid circular locking dependency in ser_state_run() Date: Wed, 20 Aug 2025 17:13:46 +0300 Message-ID: <20250820141441.106156-3-pchelkin@ispras.ru> X-Mailer: git-send-email 2.50.1 In-Reply-To: <20250820141441.106156-1-pchelkin@ispras.ru> References: <20250820141441.106156-1-pchelkin@ispras.ru> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Lockdep gives a splat [1] when ser_hdl_work item is executed. It is scheduled at mac80211 workqueue via ieee80211_queue_work() and takes a wiphy lock inside. However, this workqueue can be flushed when e.g. closing the interface and wiphy lock is already taken in that case. Choosing wiphy_work_queue() for SER is likely not suitable. Back on to global workqueue. [1]: WARNING: possible circular locking dependency detected 6.17.0-rc2 #17 Not tainted ------------------------------------------------------ kworker/u32:1/61 is trying to acquire lock: ffff88811bc00768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ser_state_run+0x5e/0x= 180 [rtw89_core] but task is already holding lock: ffffc9000048fd30 ((work_completion)(&ser->ser_hdl_work)){+.+.}-{0:0}, at: = process_one_work+0x7b5/0x1450 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #2 ((work_completion)(&ser->ser_hdl_work)){+.+.}-{0:0}: process_one_work+0x7c6/0x1450 worker_thread+0x49e/0xd00 kthread+0x313/0x640 ret_from_fork+0x221/0x300 ret_from_fork_asm+0x1a/0x30 -> #1 ((wq_completion)phy0){+.+.}-{0:0}: touch_wq_lockdep_map+0x8e/0x180 __flush_workqueue+0x129/0x10d0 ieee80211_stop_device+0xa8/0x110 ieee80211_do_stop+0x14ce/0x2880 ieee80211_stop+0x13a/0x2c0 __dev_close_many+0x18f/0x510 __dev_change_flags+0x25f/0x670 netif_change_flags+0x7b/0x160 do_setlink.isra.0+0x1640/0x35d0 rtnl_newlink+0xd8c/0x1d30 rtnetlink_rcv_msg+0x700/0xb80 netlink_rcv_skb+0x11d/0x350 netlink_unicast+0x49a/0x7a0 netlink_sendmsg+0x759/0xc20 ____sys_sendmsg+0x812/0xa00 ___sys_sendmsg+0xf7/0x180 __sys_sendmsg+0x11f/0x1b0 do_syscall_64+0xbb/0x360 entry_SYSCALL_64_after_hwframe+0x77/0x7f -> #0 (&rdev->wiphy.mtx){+.+.}-{4:4}: __lock_acquire+0x124c/0x1d20 lock_acquire+0x154/0x2e0 __mutex_lock+0x17b/0x12f0 ser_state_run+0x5e/0x180 [rtw89_core] rtw89_ser_hdl_work+0x119/0x220 [rtw89_core] process_one_work+0x82d/0x1450 worker_thread+0x49e/0xd00 kthread+0x313/0x640 ret_from_fork+0x221/0x300 ret_from_fork_asm+0x1a/0x30 other info that might help us debug this: Chain exists of: &rdev->wiphy.mtx --> (wq_completion)phy0 --> (work_completion)(&ser->ser= _hdl_work) Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock((work_completion)(&ser->ser_hdl_work)); lock((wq_completion)phy0); lock((work_completion)(&ser->ser_hdl_work)); lock(&rdev->wiphy.mtx); *** DEADLOCK *** 2 locks held by kworker/u32:1/61: #0: ffff888103835148 ((wq_completion)phy0){+.+.}-{0:0}, at: process_one_w= ork+0xefa/0x1450 #1: ffffc9000048fd30 ((work_completion)(&ser->ser_hdl_work)){+.+.}-{0:0},= at: process_one_work+0x7b5/0x1450 stack backtrace: CPU: 0 UID: 0 PID: 61 Comm: kworker/u32:1 Not tainted 6.17.0-rc2 #17 PREEM= PT(voluntary) Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS edk2-20250523-= 14.fc42 05/23/2025 Workqueue: phy0 rtw89_ser_hdl_work [rtw89_core] Call Trace: dump_stack_lvl+0x5d/0x80 print_circular_bug.cold+0x178/0x1be check_noncircular+0x14c/0x170 __lock_acquire+0x124c/0x1d20 lock_acquire+0x154/0x2e0 __mutex_lock+0x17b/0x12f0 ser_state_run+0x5e/0x180 [rtw89_core] rtw89_ser_hdl_work+0x119/0x220 [rtw89_core] process_one_work+0x82d/0x1450 worker_thread+0x49e/0xd00 kthread+0x313/0x640 ret_from_fork+0x221/0x300 ret_from_fork_asm+0x1a/0x30 Found by Linux Verification Center (linuxtesting.org). Fixes: ebfc9199df05 ("wifi: rtw89: add wiphy_lock() to work that isn't held= wiphy_lock() yet") Signed-off-by: Fedor Pchelkin --- The whole log is attached below. The issue itself which triggers SER activity is quite reliably reproduced on my side when VM is booted with passthrough rtw89_8852be (vfio-pci) and debugger enabled. The card then recovers and works without visible failures. [ 8.085405] rtw89_8852be 0000:00:05.0: loaded firmware rtw89/rtw8852b_fw= -1.bin [ 8.319767] ACPI: \_SB_.LNKA: Enabled at IRQ 10 [ 8.391400] rtw89_8852be 0000:00:05.0: Firmware version 0.29.128.0 (418a= 672d), cmd version 0, type 5 [ 8.392051] rtw89_8852be 0000:00:05.0: Firmware version 0.29.128.0 (418a= 672d), cmd version 0, type 3 [ 8.554083] systemd-tmpfile (252) used greatest stack depth: 24152 bytes= left [ 8.834526] rtw89_8852be 0000:00:05.0: chip rfe_type is 1 [ 8.920602] rtw89_8852be 0000:00:05.0: rfkill hardware state changed to = enable [ 8.943191] rtw89_8852be 0000:00:05.0 wlp0s5: renamed from wlan0 ... [ 50.425636] rtw89_8852be 0000:00:05.0: FW status =3D 0x1e001500 [ 50.426438] rtw89_8852be 0000:00:05.0: FW BADADDR =3D 0x40000000 [ 50.427084] rtw89_8852be 0000:00:05.0: FW EPC/RA =3D 0xb898fc27 [ 50.427746] rtw89_8852be 0000:00:05.0: FW MISC =3D 0xb898cd8b [ 50.428664] rtw89_8852be 0000:00:05.0: R_AX_HALT_C2H =3D 0x10002020 [ 50.429642] rtw89_8852be 0000:00:05.0: R_AX_SER_DBG_INFO =3D 0xf00000b2 [ 50.430506] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7451 [ 50.431947] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7451 [ 50.432903] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7451 [ 50.433730] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a744d [ 50.434511] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a744d [ 50.435319] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7451 [ 50.436074] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a744d [ 50.436774] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a744b [ 50.437537] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7449 [ 50.438388] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a744b [ 50.439409] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7451 [ 50.440222] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a744d [ 50.440945] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a744f [ 50.441567] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7449 [ 50.442312] rtw89_8852be 0000:00:05.0: [ERR]fw PC =3D 0xb89a7453 [ 50.442974] rtw89_8852be 0000:00:05.0: ---> err=3D0x5000 [ 50.443712] rtw89_8852be 0000:00:05.0: R_AX_SER_DBG_INFO =3D0xf00000b2 [ 50.444460] rtw89_8852be 0000:00:05.0: R_AX_SER_DBG_INFO =3D0xf00000b2 [ 50.445306] rtw89_8852be 0000:00:05.0: DBG Counter 1 (R_AX_DRV_FW_HSK_4)= =3D0xdeadbeef [ 50.446235] rtw89_8852be 0000:00:05.0: DBG Counter 2 (R_AX_DRV_FW_HSK_5)= =3D0xdeadbeef [ 50.447035] rtw89_8852be 0000:00:05.0: R_AX_DMAC_ERR_ISR=3D0x00000000 [ 50.447746] rtw89_8852be 0000:00:05.0: R_AX_DMAC_ERR_IMR=3D0xffffffff [ 50.448504] rtw89_8852be 0000:00:05.0: R_AX_CMAC_ERR_ISR [0]=3D0x00000000 [ 50.449434] rtw89_8852be 0000:00:05.0: R_AX_CMAC_FUNC_EN [0]=3D0xf000003f [ 50.450266] rtw89_8852be 0000:00:05.0: R_AX_CK_EN [0]=3D0xffffffff [ 50.451150] rtw89_8852be 0000:00:05.0: R_AX_CMAC_ERR_IMR [0]=3D0xffffffff [ 50.452232] rtw89_8852be 0000:00:05.0: [CMAC] : CMAC1 not enabled [ 50.453025] rtw89_8852be 0000:00:05.0: R_AX_RPQ_RXBD_IDX =3D0x00250025 [ 50.453737] rtw89_8852be 0000:00:05.0: R_AX_DBG_ERR_FLAG=3D0x10000000 [ 50.454552] rtw89_8852be 0000:00:05.0: R_AX_LBC_WATCHDOG=3D0x00000081 [ 50.455365] rtw89_8852be 0000:00:05.0: <--- [ 50.455926] rtw89_8852be 0000:00:05.0: SER catches error: 0x5000 [ 50.457154] =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D=3D=3D=3D=3D [ 50.458143] WARNING: possible circular locking dependency detected [ 50.458981] 6.17.0-rc2 #17 Not tainted [ 50.459746] ------------------------------------------------------ [ 50.460561] kworker/u32:1/61 is trying to acquire lock: [ 50.461305] ffff88811bc00768 (&rdev->wiphy.mtx){+.+.}-{4:4}, at: ser_sta= te_run+0x5e/0x180 [rtw89_core] [ 50.462629]=20 but task is already holding lock: [ 50.463449] ffffc9000048fd30 ((work_completion)(&ser->ser_hdl_work)){+.+= .}-{0:0}, at: process_one_work+0x7b5/0x1450 [ 50.464934]=20 which lock already depends on the new lock. [ 50.466034]=20 the existing dependency chain (in reverse order) is: [ 50.467040]=20 -> #2 ((work_completion)(&ser->ser_hdl_work)){+.+.}-{0:0}: [ 50.468133] process_one_work+0x7c6/0x1450 [ 50.468797] worker_thread+0x49e/0xd00 [ 50.469381] kthread+0x313/0x640 [ 50.469938] ret_from_fork+0x221/0x300 [ 50.470523] ret_from_fork_asm+0x1a/0x30 [ 50.471179]=20 -> #1 ((wq_completion)phy0){+.+.}-{0:0}: [ 50.472038] touch_wq_lockdep_map+0x8e/0x180 [ 50.472524] __flush_workqueue+0x129/0x10d0 [ 50.473112] ieee80211_stop_device+0xa8/0x110 [ 50.473680] ieee80211_do_stop+0x14ce/0x2880 [ 50.474411] ieee80211_stop+0x13a/0x2c0 [ 50.474905] __dev_close_many+0x18f/0x510 [ 50.475362] __dev_change_flags+0x25f/0x670 [ 50.475950] netif_change_flags+0x7b/0x160 [ 50.476461] do_setlink.isra.0+0x1640/0x35d0 [ 50.477007] rtnl_newlink+0xd8c/0x1d30 [ 50.477453] rtnetlink_rcv_msg+0x700/0xb80 [ 50.478073] netlink_rcv_skb+0x11d/0x350 [ 50.478558] netlink_unicast+0x49a/0x7a0 [ 50.479064] netlink_sendmsg+0x759/0xc20 [ 50.479511] ____sys_sendmsg+0x812/0xa00 [ 50.479992] ___sys_sendmsg+0xf7/0x180 [ 50.480423] __sys_sendmsg+0x11f/0x1b0 [ 50.480933] do_syscall_64+0xbb/0x360 [ 50.481356] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 50.481959]=20 -> #0 (&rdev->wiphy.mtx){+.+.}-{4:4}: [ 50.482578] __lock_acquire+0x124c/0x1d20 [ 50.483072] lock_acquire+0x154/0x2e0 [ 50.483490] __mutex_lock+0x17b/0x12f0 [ 50.483963] ser_state_run+0x5e/0x180 [rtw89_core] [ 50.484518] rtw89_ser_hdl_work+0x119/0x220 [rtw89_core] [ 50.485149] process_one_work+0x82d/0x1450 [ 50.485620] worker_thread+0x49e/0xd00 [ 50.486092] kthread+0x313/0x640 [ 50.486484] ret_from_fork+0x221/0x300 [ 50.486958] ret_from_fork_asm+0x1a/0x30 [ 50.487419]=20 other info that might help us debug this: [ 50.488290] Chain exists of: &rdev->wiphy.mtx --> (wq_completion)phy0 --> (work_complet= ion)(&ser->ser_hdl_work) [ 50.489752] Possible unsafe locking scenario: [ 50.490351] CPU0 CPU1 [ 50.490866] ---- ---- [ 50.491320] lock((work_completion)(&ser->ser_hdl_work)); [ 50.491951] lock((wq_completion)phy0); [ 50.492622] lock((work_completion)(&ser->= ser_hdl_work)); [ 50.493459] lock(&rdev->wiphy.mtx); [ 50.493884]=20 *** DEADLOCK *** [ 50.494467] 2 locks held by kworker/u32:1/61: [ 50.494969] #0: ffff888103835148 ((wq_completion)phy0){+.+.}-{0:0}, at:= process_one_work+0xefa/0x1450 [ 50.495919] #1: ffffc9000048fd30 ((work_completion)(&ser->ser_hdl_work)= ){+.+.}-{0:0}, at: process_one_work+0x7b5/0x1450 [ 50.497017]=20 stack backtrace: [ 50.497459] CPU: 0 UID: 0 PID: 61 Comm: kworker/u32:1 Not tainted 6.17.0= -rc2 #17 PREEMPT(voluntary)=20 [ 50.497465] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS = edk2-20250523-14.fc42 05/23/2025 [ 50.497470] Workqueue: phy0 rtw89_ser_hdl_work [rtw89_core] [ 50.497503] Call Trace: [ 50.497506] [ 50.497509] dump_stack_lvl+0x5d/0x80 [ 50.497517] print_circular_bug.cold+0x178/0x1be [ 50.497525] check_noncircular+0x14c/0x170 [ 50.497535] __lock_acquire+0x124c/0x1d20 [ 50.497543] ? ret_from_fork_asm+0x1a/0x30 [ 50.497550] lock_acquire+0x154/0x2e0 [ 50.497555] ? ser_state_run+0x5e/0x180 [rtw89_core] [ 50.497586] ? ser_state_run+0x5e/0x180 [rtw89_core] [ 50.497610] __mutex_lock+0x17b/0x12f0 [ 50.497616] ? ser_state_run+0x5e/0x180 [rtw89_core] [ 50.497643] ? srso_alias_return_thunk+0x5/0xfbef5 [ 50.497648] ? __lock_acquire+0xcc3/0x1d20 [ 50.497654] ? __pfx___mutex_lock+0x10/0x10 [ 50.497662] ? srso_alias_return_thunk+0x5/0xfbef5 [ 50.497676] ? do_raw_spin_lock+0x128/0x260 [ 50.497680] ? find_held_lock+0x2b/0x80 [ 50.497688] ? ser_state_run+0x5e/0x180 [rtw89_core] [ 50.497713] ser_state_run+0x5e/0x180 [rtw89_core] [ 50.497740] rtw89_ser_hdl_work+0x119/0x220 [rtw89_core] [ 50.497768] process_one_work+0x82d/0x1450 [ 50.497779] ? __pfx_process_one_work+0x10/0x10 [ 50.497784] ? srso_alias_return_thunk+0x5/0xfbef5 [ 50.497791] ? srso_alias_return_thunk+0x5/0xfbef5 [ 50.497795] ? assign_work+0x167/0x240 [ 50.497799] ? srso_alias_return_thunk+0x5/0xfbef5 [ 50.497805] worker_thread+0x49e/0xd00 [ 50.497816] ? __pfx_worker_thread+0x10/0x10 [ 50.497820] kthread+0x313/0x640 [ 50.497827] ? __pfx_kthread+0x10/0x10 [ 50.497830] ? ret_from_fork+0x18/0x300 [ 50.497836] ? srso_alias_return_thunk+0x5/0xfbef5 [ 50.497840] ? lock_release+0xc6/0x2c0 [ 50.497845] ? __pfx_kthread+0x10/0x10 [ 50.497851] ret_from_fork+0x221/0x300 [ 50.497855] ? __pfx_kthread+0x10/0x10 [ 50.497860] ret_from_fork_asm+0x1a/0x30 [ 50.497871] [ 50.565573] rtw89_8852be 0000:00:05.0: firmware failed to ack for leavin= g ps mode [ 50.876040] clocksource: Long readout interval, skipping watchdog check:= cs_nsec: 57471994482 wd_nsec: 502738831 [ 53.429036] rtw89_8852be 0000:00:05.0: c2h reg timeout [ 53.480222] rtw89_8852be 0000:00:05.0: rtw89: failed to leave lps state [ 53.483649] rtw89_8852be 0000:00:05.0: FW backtrace invalid key: 0x66383= 938 [ 53.699956] ieee80211 phy0: Hardware restart was requested drivers/net/wireless/realtek/rtw89/ser.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/wireless/realtek/rtw89/ser.c b/drivers/net/wireles= s/realtek/rtw89/ser.c index bb39fdbcba0d..6c0a13a854f6 100644 --- a/drivers/net/wireless/realtek/rtw89/ser.c +++ b/drivers/net/wireless/realtek/rtw89/ser.c @@ -205,7 +205,6 @@ static void rtw89_ser_hdl_work(struct work_struct *work) =20 static int ser_send_msg(struct rtw89_ser *ser, u8 event) { - struct rtw89_dev *rtwdev =3D container_of(ser, struct rtw89_dev, ser); struct ser_msg *msg =3D NULL; =20 if (test_bit(RTW89_SER_DRV_STOP_RUN, ser->flags)) @@ -221,7 +220,7 @@ static int ser_send_msg(struct rtw89_ser *ser, u8 event) list_add(&msg->list, &ser->msg_q); spin_unlock_irq(&ser->msg_q_lock); =20 - ieee80211_queue_work(rtwdev->hw, &ser->ser_hdl_work); + schedule_work(&ser->ser_hdl_work); return 0; } =20 --=20 2.50.1