INFO: task syz.2.1192:9504 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc4-syzkaller-00321-g300386d117a9 #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.2.1192      state:D
 stack:27736 pid:9504  tgid:9503  ppid:2952   task_flags:0x40044c flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x132a/0x3b10 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6878
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
 rwsem_down_write_slowpath+0x524/0x1310 kernel/locking/rwsem.c:1176
 __down_write_common kernel/locking/rwsem.c:1304 [inline]
 __down_write kernel/locking/rwsem.c:1313 [inline]
 down_write+0x1d6/0x200 kernel/locking/rwsem.c:1578
 kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1712
 sysfs_remove_file include/linux/sysfs.h:777 [inline]
 driver_remove_file drivers/base/driver.c:201 [inline]
 driver_remove_file+0x4a/0x60 drivers/base/driver.c:197
 remove_bind_files drivers/base/bus.c:605 [inline]
 bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743
 driver_unregister+0x76/0xb0 drivers/base/driver.c:277
 usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1732
 raw_release+0x1ae/0x2b0 drivers/usb/gadget/legacy/raw_gadget.c:462
 __fput+0x402/0xb70 fs/file_table.c:465
 task_work_run+0x150/0x240 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x86c/0x2bd0 kernel/exit.c:964
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
 get_signal+0x2673/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x7c/0xe0 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x3e9/0x4b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8c393ee52b
RSP: 002b:00007f8c37a54f10 EFLAGS: 00000246
 ORIG_RAX: 0000000000000010
RAX: fffffffffffffffc RBX: 0000000000000003 RCX: 00007f8c393ee52b
RDX: 00007f8c37a55fe0 RSI: 0000000080085502 RDI: 0000000000000003
RBP: 00007f8c37a55fe0 R08: 0000000000000080 R09: 00007f8c37a54fd8
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502
R13: 0000000800000000 R14: 0000000000000008 R15: 00007f8c3947c0f4
 </TASK>
INFO: task syz.0.1194:9508 blocked for more than 144 seconds.
      Not tainted 6.16.0-rc4-syzkaller-00321-g300386d117a9 #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1194      state:D
 stack:27736 pid:9508  tgid:9507  ppid:2955   task_flags:0x40044c flags:0x00004006
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x132a/0x3b10 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0xe7/0x3a0 kernel/sched/core.c:6878
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
 rwsem_down_write_slowpath+0x524/0x1310 kernel/locking/rwsem.c:1176
 __down_write_common kernel/locking/rwsem.c:1304 [inline]
 __down_write kernel/locking/rwsem.c:1313 [inline]
 down_write+0x1d6/0x200 kernel/locking/rwsem.c:1578
 kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1712
 sysfs_remove_file include/linux/sysfs.h:777 [inline]
 driver_remove_file drivers/base/driver.c:201 [inline]
 driver_remove_file+0x4a/0x60 drivers/base/driver.c:197
 remove_bind_files drivers/base/bus.c:605 [inline]
 bus_remove_driver+0x224/0x2c0 drivers/base/bus.c:743
 driver_unregister+0x76/0xb0 drivers/base/driver.c:277
 usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1732
 raw_release+0x1ae/0x2b0 drivers/usb/gadget/legacy/raw_gadget.c:462
 __fput+0x402/0xb70 fs/file_table.c:465
 task_work_run+0x150/0x240 kernel/task_work.c:227
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x86c/0x2bd0 kernel/exit.c:964
 do_group_exit+0xd3/0x2a0 kernel/exit.c:1105
 get_signal+0x2673/0x26d0 kernel/signal.c:3034
 arch_do_signal_or_restart+0x8f/0x7d0 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop+0x7c/0xe0 kernel/entry/common.c:111
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x3e9/0x4b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f55efe8e52b
RSP: 002b:00007f55ee4ecf10 EFLAGS: 00000246
 ORIG_RAX: 0000000000000010
RAX: fffffffffffffffc RBX: 0000000000000004 RCX: 00007f55efe8e52b
RDX: 00007f55ee4edfe0 RSI: 0000000080085502 RDI: 0000000000000004
RBP: 00007f55ee4edfe0 R08: 0000000000000000 R09: 00302e6364755f79
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000080085502
R13: 0000000800000000 R14: 00002000000000c0 R15: 00007f55eff1c0f4
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/30:
 #0: ffffffff890c7ec0
 (
rcu_read_lock
){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770
8 locks held by kworker/1:1/42:
1 lock held by udevd/2842:
 #0: ffff888100ac4988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180
2 locks held by getty/2904:
 #0: 
ffff8881123310a0 (
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: 
ffffc900000432f0
 (
&ldata->atomic_read_lock){+.+.}-{4:4}
, at: n_tty_read+0x41b/0x14f0 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/2951:
 #0: ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162
1 lock held by syz-executor/2952:
 #0: 
ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162
1 lock held by syz-executor/2954:
 #0: ffff888100ac4988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162
1 lock held by syz-executor/2955:
 #0: 
ffff888100ac4988 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162
1 lock held by syz-executor/2959:
 #0: 
ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162
4 locks held by udevd/5209:
 #0: 
ffff88810ab7bb08
 (
&p->lock){+.+.}-{4:4}
, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182
 #1: 
ffff8881138bfc88 (
&of->mutex
#2
){+.+.}-{4:4}
, at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154
 #2: 
ffff88811f110a58
 (kn->active
#9){++++}-{0:0}
, at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155
 #3: 
ffff888137b88198 (
&dev->mutex
){....}-{4:4}
, at: device_lock_interruptible include/linux/device.h:889 [inline]
, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142
5 locks held by kworker/0:3/5227:
 #0: 
ffff888107692148 (
(wq_completion)usb_hub_wq){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
 #1: 
ffffc90003b4fd10
 (
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
 #2: 
ffff88810b741198
 (&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5894
 #3: 
ffff88812355a198 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: usb_disconnect+0x10a/0x9c0 drivers/usb/core/hub.c:2335
 #4: 
ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}, at: kernfs_find_and_get_ns+0x2f/0x70 fs/kernfs/dir.c:933
5 locks held by kworker/1:3/5233:
 #0: 
ffff888107692148 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
 #1: ffffc90003adfd10
 (
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
 #2: 
ffff88810b729198
 (&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5894
 #3: ffff888110293198
 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: usb_disconnect+0x10a/0x9c0 drivers/usb/core/hub.c:2335
 #4: 
ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1712
5 locks held by kworker/1:4/5237:
 #0: ffff888107692148
 (
(wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
 #1: 
ffffc90003b8fd10 (
(work_completion)(&hub->events)){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
 #2: 
ffff888109709198 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5894
 #3: 
ffff888137b88198
 (
&dev->mutex){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: __device_attach+0x7e/0x4b0 drivers/base/dd.c:1004
 #4: 
ffff888100ac4988 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:791
4 locks held by kworker/1:7/5253:
 #0: 
ffff888107692148
 ((wq_completion)usb_hub_wq
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
 #1: 
ffffc90003abfd10 (
(work_completion)(&hub->events)
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
 #2: 
ffff88810afaf198
 (
&dev->mutex){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5894
 #3: 
ffff888100ac4988 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:791
4 locks held by kworker/0:6/5760:
 #0: 
ffff888100080d48
 ((wq_completion)events
){+.+.}-{0:0}
, at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213
 #1: 
ffffc900127e7d10 (
kernfs_notify_work
){+.+.}-{0:0}
, at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214
 #2: 
ffff888100ac4ab8
 (
&root->kernfs_supers_rwsem){++++}-{4:4}
, at: kernfs_notify_workfn+0xf7/0xb30 fs/kernfs/file.c:914
 #3: 
ffff888100ac4988 (
&root->kernfs_rwsem){++++}-{4:4}
, at: kernfs_notify_workfn+0xff/0xb30 fs/kernfs/file.c:915
1 lock held by syz.1.1191/9502:
 #0: ffff888100ac4988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1712
1 lock held by syz.2.1192/9504:
1 lock held by syz.0.1194/9508:
 #0: ffff888100ac4988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_remove_by_name_ns+0x3d/0x110 fs/kernfs/dir.c:1712
2 locks held by syz.3.1195/9510:
 #0: 
ffff88810afbcd78 (
&dev->mutex
){....}-{4:4}
, at: device_lock include/linux/device.h:884 [inline]
, at: __device_driver_lock drivers/base/dd.c:1094 [inline]
, at: __driver_attach+0x278/0x580 drivers/base/dd.c:1214
 #1: ffff888100ac4988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_add_one+0x38/0x840 fs/kernfs/dir.c:791
1 lock held by syz-executor/9511:
 #0: ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180
1 lock held by syz-executor/9512:
 #0: 
ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180
1 lock held by syz-executor/9513:
 #0: ffff888100ac4988
 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180
1 lock held by syz-executor/9514:
 #0: 
ffff888100ac4988 (
&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180
1 lock held by syz-executor/9515:
 #0: 
ffff888100ac4988
 (&root->kernfs_rwsem
){++++}-{4:4}
, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.16.0-rc4-syzkaller-00321-g300386d117a9 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:307 [inline]
 watchdog+0xf70/0x12c0 kernel/hung_task.c:470
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5b3/0x6c0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
yealink 2-1:36.0: unexpected response 0
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 42 Comm: kworker/1:1 Not tainted 6.16.0-rc4-syzkaller-00321-g300386d117a9 #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events_power_efficient gc_worker
RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:416
Code: 48 8d 7d 40 44 89 e1 48 b8 00 00 00 00 00 fc ff df 48 89 fa d3 e3 48 c1 ea 03 80 3c 02 00 75 1c 66 03 5d 40 44 89 e8 89 da ee <5b> 5d 41 5c 41 5d c3 cc cc cc cc e8 61 40 05 ff eb a0 e8 ea 40 05
RSP: 0018:ffffc900001a84f0 EFLAGS: 00000002
RAX: 000000000000005b RBX: 00000000000003f8 RCX: 0000000000000000
RDX: 00000000000003f8 RSI: ffffffff82d59275 RDI: ffffffff93928fc0
RBP: ffffffff93928f80 R08: 0000000000000001 R09: 000000000000001f
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: 000000000000005b R14: ffffffff93928f80 R15: ffffffff82d59210
FS:  0000000000000000(0000) GS:ffff888269262000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fcdbe0724c0 CR3: 0000000116f1c000 CR4: 00000000003506f0
Call Trace:
 <IRQ>
 serial_port_out include/linux/serial_core.h:798 [inline]
 serial8250_console_putchar drivers/tty/serial/8250/8250_port.c:3306 [inline]
 serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3378 [inline]
 serial8250_console_write+0xfbc/0x1890 drivers/tty/serial/8250/8250_port.c:3456
 console_emit_next_record kernel/printk/printk.c:3138 [inline]
 console_flush_all+0x801/0xc60 kernel/printk/printk.c:3226
 __console_flush_and_unlock kernel/printk/printk.c:3285 [inline]
 console_unlock+0xd8/0x210 kernel/printk/printk.c:3325
 vprintk_emit+0x418/0x6d0 kernel/printk/printk.c:2450
 dev_vprintk_emit drivers/base/core.c:4917 [inline]
 dev_printk_emit+0xfa/0x140 drivers/base/core.c:4928
 __dev_printk+0xf5/0x270 drivers/base/core.c:4940
 _dev_err+0xe4/0x120 drivers/base/core.c:4983
 urb_irq_callback+0x12c/0x700 drivers/input/misc/yealink.c:435
 __usb_hcd_giveback_urb+0x38a/0x6e0 drivers/usb/core/hcd.c:1663
 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1747
 dummy_timer+0x1814/0x3a30 drivers/usb/gadget/udc/dummy_hcd.c:1995
 __run_hrtimer kernel/time/hrtimer.c:1761 [inline]
 __hrtimer_run_queues+0x1ff/0xad0 kernel/time/hrtimer.c:1825
 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842
 handle_softirqs+0x208/0x8d0 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xfa/0x160 kernel/softirq.c:680
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:696
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1050 [inline]
 sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline]
RIP: 0010:nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:333 [inline]
RIP: 0010:gc_worker+0x2d5/0x16d0 net/netfilter/nf_conntrack_core.c:1537
Code: 00 00 48 c7 c7 e8 24 7b 8a e8 07 31 17 fb 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 85 8a 3a fb 58 48 85 db 0f 85 d0 0f 00 00 <e8> 06 8f 3a fb 8b 1d b0 e2 37 04 41 89 dc 31 ff 41 83 e4 01 44 89
RSP: 0018:ffffc900002c7b58 EFLAGS: 00000293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff86434d69
RDX: ffff8881052fba00 RSI: ffffffff86434d78 RDI: 0000000000000007
RBP: ffffffff93a909ec R08: 0000000000000007 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000001 R12: ffff888112400000
R13: 0000000000040000 R14: dffffc0000000000 R15: 0000000000001770
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3321 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x5b3/0x6c0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>