INFO: task udevd:2846 blocked for more than 143 seconds. Not tainted 6.16.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:24520 pid:2846 tgid:2846 ppid:1 task_flags:0x400140 flags:0x00004002 Call Trace: 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_read_slowpath+0x62f/0xb60 kernel/locking/rwsem.c:1084 __down_read_common kernel/locking/rwsem.c:1248 [inline] __down_read kernel/locking/rwsem.c:1261 [inline] down_read+0xef/0x480 kernel/locking/rwsem.c:1526 kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 d_revalidate fs/namei.c:929 [inline] d_revalidate fs/namei.c:925 [inline] lookup_fast+0x266/0x610 fs/namei.c:1778 walk_component+0x5b/0x5b0 fs/namei.c:2134 link_path_walk+0x627/0xe20 fs/namei.c:2506 path_lookupat+0x15a/0x6d0 fs/namei.c:2662 filename_lookup+0x224/0x5f0 fs/namei.c:2692 do_readlinkat+0xce/0x3a0 fs/stat.c:576 __do_sys_readlink fs/stat.c:613 [inline] __se_sys_readlink fs/stat.c:610 [inline] __x64_sys_readlink+0x78/0xc0 fs/stat.c:610 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc8216683a7 RSP: 002b:00007fff740d2e18 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 00007fff740d32f0 RCX: 00007fc8216683a7 RDX: 0000000000000400 RSI: 00007fff740d2e20 RDI: 00007fff740d32f0 RBP: 00007fff740d2e20 R08: 0000000000000075 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000400 R13: 000055642c886100 R14: 0000000000000001 R15: 00007fff740d4bf0 INFO: task syz.2.239:8275 blocked for more than 143 seconds. Not tainted 6.16.0-rc1-syzkaller #0 Blocked by coredump. "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.2.239 state:D stack:27720 pid:8275 tgid:8275 ppid:5212 task_flags:0x40044c flags:0x00004006 Call Trace: 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+0x14d/0x240 kernel/task_work.c:227 exit_task_work include/linux/task_work.h:40 [inline] do_exit+0x864/0x2bd0 kernel/exit.c:955 do_group_exit+0xd3/0x2a0 kernel/exit.c:1104 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: 0033:0x7f679097e929 RSP: 002b:00007ffdc1533b28 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: fffffffffffffdfc RBX: 0000000000044e82 RCX: 00007f679097e929 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f6790ba616c RBP: 000000000000015e R08: 00007f6790b78000 R09: 00000013c1533e1f R10: 00007ffdc1533c20 R11: 0000000000000246 R12: 00007f6790ba616c R13: 00007ffdc1533c20 R14: 0000000000044fe0 R15: 00007ffdc1533c40 INFO: task syz.0.241:8281 blocked for more than 144 seconds. Not tainted 6.16.0-rc1-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.0.241 state:D stack:29080 pid:8281 tgid:8280 ppid:5207 task_flags:0x400040 flags:0x00004004 Call Trace: 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_register_driver_owner+0x20f/0x330 drivers/usb/gadget/udc/core.c:1722 raw_ioctl_run drivers/usb/gadget/legacy/raw_gadget.c:595 [inline] raw_ioctl+0x17d0/0x2c30 drivers/usb/gadget/legacy/raw_gadget.c:1306 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl fs/ioctl.c:893 [inline] __x64_sys_ioctl+0x18b/0x210 fs/ioctl.c:893 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xcd/0x4b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f33f382e52b RSP: 002b:00007f33f1e94f10 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007f33f382e52b RDX: 0000000000000000 RSI: 0000000000005501 RDI: 0000000000000004 RBP: 00007f33f1e95fe0 R08: 0000000000000000 R09: 00302e6364755f79 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f33f1e94fb0 R14: 0000200000000280 R15: 00007f33f3b80b88 Showing all locks held in the system: 5 locks held by kworker/0:1/10: 8 locks held by kworker/1:0/23: #0: ffff8881026fe948 ( (wq_completion)usb_hub_wq){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000018fd10 ( (work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810afc5198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:884 [inline] , at: hub_event+0x1be/0x5030 drivers/usb/core/hub.c:5863 #3: ffff888116cc1198 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:884 [inline] , at: usb_disconnect+0x10a/0x920 drivers/usb/core/hub.c:2307 #4: ffff88811b60b160 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:884 [inline] , at: __device_driver_lock drivers/base/dd.c:1094 [inline] , at: device_release_driver_internal+0xa4/0x620 drivers/base/dd.c:1292 #5: ffff88811d194c90 (&gspca_dev->usb_lock ){+.+.}-{4:4} , at: gspca_disconnect+0xb8/0x350 drivers/media/usb/gspca/gspca.c:1628 #6: ffffffff89e00108 (input_mutex ){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:225 [inline] , at: __input_unregister_device+0x156/0x470 drivers/input/input.c:2221 #7: ffffffff890d3378 ( rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x284/0x3c0 kernel/rcu/tree_exp.h:304 1 lock held by khungtaskd/30: #0: ffffffff890c7d80 ( 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 1 lock held by udevd/2846: #0: ffff888100ac4988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 2 locks held by getty/2910: #0: ffff8881083e50a0 (&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/5207: #0: ffff888100ac4988 ( &root->kernfs_rwsem ){++++}-{4:4}, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162 1 lock held by syz-executor/5209: #0: ffff888100ac4988 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162 1 lock held by syz-executor/5212: #0: ffff888100ac4988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162 1 lock held by syz-executor/5215: #0: ffff888100ac4988 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162 1 lock held by syz-executor/5218: #0: ffff888100ac4988 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1162 6 locks held by kworker/0:5/7492: 3 locks held by kworker/1:5/7522: 4 locks held by udevd/7551: #0: ffff88811e3541c8 ( &p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182 #1: ffff888134b92488 (&of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888114985b48 ( kn->active #18){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888105ab6198 ( &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 3 locks held by kworker/1:6/7600: 1 lock held by udevd/7655: #0: ffff888100ac4988 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 7 locks held by kworker/0:6/7720: 1 lock held by v4l_id/8304: #0: ffff888100ac4988 (&root->kernfs_rwsem){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 1 lock held by syz-executor/8311: #0: ffff888100ac4988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 1 lock held by syz-executor/8312: #0: ffff888100ac4988 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 1 lock held by syz-executor/8313: #0: ffff888100ac4988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 1 lock held by syz-executor/8314: #0: ffff888100ac4988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 1 lock held by syz-executor/8315: #0: ffff888100ac4988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1180 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.16.0-rc1-syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: __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+0x3c5/0x780 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 Sending NMI from CPU 1 to CPUs 0: yealink 2-1:36.0: urb_irq_callback - urb status -71 NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 7720 Comm: kworker/0:6 Not tainted 6.16.0-rc1-syzkaller #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 41 0a 08 ff eb a0 e8 ca 0a 08 RSP: 0018:ffffc900000074f0 EFLAGS: 00000002 RAX: 000000000000005b RBX: 00000000000003f8 RCX: 0000000000000000 RDX: 00000000000003f8 RSI: ffffffff82d2a7c5 RDI: ffffffff9390bc00 RBP: ffffffff9390bbc0 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 000000000000005b R14: ffffffff9390bbc0 R15: ffffffff82d2a760 FS: 0000000000000000(0000) GS:ffff88826917f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f6790cd3000 CR3: 0000000008ea4000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: 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+0xfbf/0x1890 drivers/tty/serial/8250/8250_port.c:3456 console_emit_next_record kernel/printk/printk.c:3138 [inline] console_flush_all+0x7fe/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+0x454/0x700 drivers/input/misc/yealink.c:418 __usb_hcd_giveback_urb+0x38d/0x6e0 drivers/usb/core/hcd.c:1650 usb_hcd_giveback_urb+0x39b/0x450 drivers/usb/core/hcd.c:1734 dummy_timer+0x180e/0x3a20 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1761 [inline] __hrtimer_run_queues+0x202/0xad0 kernel/time/hrtimer.c:1825 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1842 handle_softirqs+0x205/0x8d0 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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:arch_atomic_read arch/x86/include/asm/atomic.h:23 [inline] RIP: 0010:raw_atomic_read include/linux/atomic/atomic-arch-fallback.h:457 [inline] RIP: 0010:rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline] RIP: 0010:rcu_is_watching+0x5c/0xc0 kernel/rcu/tree.c:745 Code: 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 75 5c 48 03 1c ed 80 2b ba 88 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <0f> b6 14 02 48 89 d8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 24 8b RSP: 0018:ffffc9000201fac8 EFLAGS: 00000a06 RAX: dffffc0000000000 RBX: ffff8881f5832fa8 RCX: 0000000000000002 RDX: 1ffff1103eb065f5 RSI: ffffffff8768a200 RDI: ffffffff88ba2b80 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000040000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 trace_lock_acquire include/trace/events/lock.h:24 [inline] lock_acquire+0x2cd/0x350 kernel/locking/lockdep.c:5834 rcu_lock_acquire include/linux/rcupdate.h:331 [inline] rcu_read_lock include/linux/rcupdate.h:841 [inline] gc_worker+0x241/0x16d0 net/netfilter/nf_conntrack_core.c:1535 process_one_work+0x9cf/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3321 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3402 kthread+0x3c5/0x780 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