INFO: task syz.1.18:5070 blocked for more than 144 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.18        state:D stack:27824 pid: 5070 ppid:  4801 flags:0x00104006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 vivid_fop_release+0x66/0xad0 drivers/media/test-drivers/vivid/vivid-core.c:632
 v4l2_release+0x1f9/0x390 drivers/media/v4l2-core/v4l2-dev.c:456
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 get_signal+0x122e/0x12d0 kernel/signal.c:2672
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f31239e6679
RSP: 002b:00007f312304a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007f3123c51fa0 RCX: 00007f31239e6679
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007f3123a79ee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3123c52038 R14: 00007f3123c51fa0 R15: 00007fff12c4c798
 </TASK>
INFO: task syz.3.20:5073 blocked for more than 145 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.20        state:D stack:27824 pid: 5073 ppid:  4804 flags:0x00104006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 get_signal+0x122e/0x12d0 kernel/signal.c:2672
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7feb4c0e0679
RSP: 002b:00007feb4b744028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007feb4c34bfa0 RCX: 00007feb4c0e0679
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007feb4c173ee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007feb4c34c038 R14: 00007feb4c34bfa0 R15: 00007fffc2e988b8
 </TASK>
INFO: task syz.4.21:5076 blocked for more than 147 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.21        state:D stack:27824 pid: 5076 ppid:  4807 flags:0x00104006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 get_signal+0x122e/0x12d0 kernel/signal.c:2672
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa2795e4679
RSP: 002b:00007fa278c48028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007fa27984ffa0 RCX: 00007fa2795e4679
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007fa279677ee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa279850038 R14: 00007fa27984ffa0 R15: 00007ffffb1e35b8
 </TASK>
INFO: task syz.0.17:5080 blocked for more than 148 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.17        state:D stack:27824 pid: 5080 ppid:  4791 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 get_signal+0x122e/0x12d0 kernel/signal.c:2672
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fa8ea237679
RSP: 002b:00007fa8e989b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007fa8ea4a2fa0 RCX: 00007fa8ea237679
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007fa8ea2caee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa8ea4a3038 R14: 00007fa8ea4a2fa0 R15: 00007ffdbd8a35c8
 </TASK>
INFO: task syz.5.22:5165 blocked for more than 149 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.22        state:D stack:27320 pid: 5165 ppid:  5146 flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6537
 __mutex_lock_common+0xcfc/0x2400 kernel/locking/mutex.c:669
 __mutex_lock kernel/locking/mutex.c:729 [inline]
 mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
 v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 __fput+0x234/0x930 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 get_signal+0x122e/0x12d0 kernel/signal.c:2672
 arch_do_signal_or_restart+0xe7/0x12c0 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdd59caf679
RSP: 002b:00007fdd59313028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: fffffffffffffe00 RBX: 00007fdd59f1afa0 RCX: 00007fdd59caf679
RDX: 0000200000000100 RSI: 00000000c100565c RDI: 0000000000000003
RBP: 00007fdd59d42ee0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fdd59f1b038 R14: 00007fdd59f1afa0 R15: 00007ffed87ef0b8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/27:
 #0: ffffffff8c31f320 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:2/154:
 #0: ffff888016dcd938 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90001ca7d00 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d431cd0 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x148/0xba0 net/core/net_namespace.c:589
 #3: ffffffff8c323da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #3: ffffffff8c323da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
3 locks held by kworker/1:2/2856:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000beefd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8c323da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:322 [inline]
 #2: ffffffff8c323da8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3a5/0x750 kernel/rcu/tree_exp.h:845
2 locks held by getty/3947:
 #0: ffff88814c8a3098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002d032e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
2 locks held by kworker/1:3/4281:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000116fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by kworker/1:4/4282:
 #0: ffff888016c72138 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90002fefd00 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by kworker/1:20/4302:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000307fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
2 locks held by kworker/0:9/4327:
 #0: ffff888016c70938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000331fd00 ((work_completion)(&pwq->unbound_release_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
1 lock held by syz.2.19/4947:
2 locks held by syz.1.18/5070:
 #0: ffff8881498d0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
 #1: ffff8881498d6aa8 (&dev->mutex#4){+.+.}-{3:3}, at: vivid_fop_release+0x66/0xad0 drivers/media/test-drivers/vivid/vivid-core.c:632
1 lock held by syz.3.20/5073:
 #0: ffff8881498d0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
1 lock held by syz.4.21/5076:
 #0: ffff8881498d0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
1 lock held by syz.0.17/5080:
 #0: ffff8881498d0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455
1 lock held by syz.5.22/5165:
 #0: ffff8881498d0448 (&mdev->req_queue_mutex){+.+.}-{3:3}, at: v4l2_release+0x1b9/0x390 drivers/media/v4l2-core/v4l2-dev.c:455

=============================================

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5002 Comm: kworker/u4:7 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: events_unbound cfg80211_wiphy_work
RIP: 0010:__lock_release kernel/locking/lockdep.c:5286 [inline]
RIP: 0010:lock_release+0x1a9/0x8a0 kernel/locking/lockdep.c:5643
Code: 85 f5 04 00 00 83 3d d9 95 2c 0c 00 0f 84 ac 03 00 00 48 8b 7c 24 18 4c 8d b7 e8 0a 00 00 4d 89 f4 49 c1 ec 03 43 0f b6 04 2c <84> c0 0f 85 ee 04 00 00 41 8b 0e 85 c9 0f 84 10 02 00 00 4c 89 64
RSP: 0018:ffffc90000007460 EFLAGS: 00000802
RAX: 0000000000000000 RBX: ffff88802c44d940 RCX: 059094eede71c500
RDX: 0000000000000000 RSI: ffffffff8a2b3f00 RDI: ffff88802c44d940
RBP: ffffc90000007570 R08: ffffffff8d89f82f R09: 1ffffffff1b13f05
R10: dffffc0000000000 R11: fffffbfff1b13f06 R12: 1ffff11005889c85
R13: dffffc0000000000 R14: ffff88802c44e428 R15: 0000000000000046
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000562d61619240 CR3: 000000005a65b000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 queue_work_on+0x124/0x1f0 kernel/workqueue.c:1559
 __ieee80211_queue_skb_to_iface net/mac80211/rx.c:222 [inline]
 ieee80211_queue_skb_to_iface net/mac80211/rx.c:232 [inline]
 ieee80211_rx_h_mgmt+0x443/0x5f0 net/mac80211/rx.c:3800
 ieee80211_rx_handlers+0x66ff/0x84c0 net/mac80211/rx.c:3964
 ieee80211_invoke_rx_handlers net/mac80211/rx.c:3994 [inline]
 ieee80211_prepare_and_rx_handle+0x1d90/0x52f0 net/mac80211/rx.c:4708
 __ieee80211_rx_handle_packet net/mac80211/rx.c:4868 [inline]
 ieee80211_rx_list+0x1c78/0x2790 net/mac80211/rx.c:4995
 ieee80211_rx_napi+0x178/0x390 net/mac80211/rx.c:5018
 ieee80211_rx include/net/mac80211.h:4573 [inline]
 ieee80211_handle_queued_frames+0x105/0x1b0 net/mac80211/main.c:237
 tasklet_action_common+0x2ad/0x410 kernel/softirq.c:806
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 do_softirq+0x142/0x210 kernel/softirq.c:477
 </IRQ>
 <TASK>
 __local_bh_enable_ip+0x180/0x1c0 kernel/softirq.c:401
 spin_unlock_bh include/linux/spinlock.h:409 [inline]
 cfg80211_bss_update+0x1c79/0x2250 net/wireless/scan.c:1913
 cfg80211_inform_single_bss_frame_data net/wireless/scan.c:2549 [inline]
 cfg80211_inform_bss_frame_data+0x89f/0x1fc0 net/wireless/scan.c:2582
 ieee80211_bss_info_update+0x6be/0xa70 net/mac80211/scan.c:190
 ieee80211_rx_bss_info net/mac80211/ibss.c:1123 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1614 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1700/0x2ab0 net/mac80211/ibss.c:1643
 ieee80211_iface_process_skb net/mac80211/iface.c:1459 [inline]
 ieee80211_iface_work+0x70e/0xc60 net/mac80211/iface.c:1513
 cfg80211_wiphy_work+0x221/0x260 net/wireless/core.c:433
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>