INFO: task kworker/0:4:5856 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00205-g586de92313fc #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:4 state:D stack:22072 pid:5856 tgid:5856 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: usb_hub_wq hub_event Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_timeout+0xb0/0x290 kernel/time/sleep_timeout.c:75 do_wait_for_common kernel/sched/completion.c:95 [inline] __wait_for_common kernel/sched/completion.c:116 [inline] wait_for_common kernel/sched/completion.c:127 [inline] wait_for_completion+0x355/0x620 kernel/sched/completion.c:148 pn533_usb_send_frame+0x30b/0x5c0 drivers/nfc/pn533/usb.c:187 __pn533_send_async+0x491/0x680 drivers/nfc/pn533/pn533.c:462 pn533_send_cmd_async drivers/nfc/pn533/pn533.c:501 [inline] pn533_send_cmd_sync drivers/nfc/pn533/pn533.c:624 [inline] pn533_get_firmware_version drivers/nfc/pn533/pn533.c:2528 [inline] pn533_finalize_setup+0x27d/0xaa0 drivers/nfc/pn533/pn533.c:2725 pn533_usb_probe+0xfcd/0x1380 drivers/nfc/pn533/usb.c:582 usb_probe_interface+0x641/0xbb0 drivers/usb/core/driver.c:396 really_probe+0x2b9/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x333/0x520 drivers/base/dd.c:1030 bus_probe_device+0x189/0x260 drivers/base/bus.c:537 device_add+0x856/0xbf0 drivers/base/core.c:3666 usb_set_configuration+0x1976/0x1fb0 drivers/usb/core/message.c:2210 usb_generic_driver_probe+0x88/0x140 drivers/usb/core/generic.c:250 usb_probe_device+0x1b8/0x380 drivers/usb/core/driver.c:291 really_probe+0x2b9/0xad0 drivers/base/dd.c:658 __driver_probe_device+0x1a2/0x390 drivers/base/dd.c:800 driver_probe_device+0x50/0x430 drivers/base/dd.c:830 __device_attach_driver+0x2d6/0x530 drivers/base/dd.c:958 bus_for_each_drv+0x24e/0x2e0 drivers/base/bus.c:462 __device_attach+0x333/0x520 drivers/base/dd.c:1030 bus_probe_device+0x189/0x260 drivers/base/bus.c:537 device_add+0x856/0xbf0 drivers/base/core.c:3666 usb_new_device+0x104a/0x19a0 drivers/usb/core/hub.c:2663 hub_port_connect drivers/usb/core/hub.c:5533 [inline] hub_port_connect_change drivers/usb/core/hub.c:5673 [inline] port_event drivers/usb/core/hub.c:5833 [inline] hub_event+0x2d6d/0x5150 drivers/usb/core/hub.c:5915 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: task udevd:6142 blocked for more than 143 seconds. Not tainted 6.14.0-rc7-syzkaller-00205-g586de92313fc #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:25176 pid:6142 tgid:6142 ppid:5210 task_flags:0x400140 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5378 [inline] __schedule+0x190e/0x4c90 kernel/sched/core.c:6765 __schedule_loop kernel/sched/core.c:6842 [inline] schedule+0x14b/0x320 kernel/sched/core.c:6857 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6914 __mutex_lock_common kernel/locking/mutex.c:662 [inline] __mutex_lock+0x817/0x1010 kernel/locking/mutex.c:730 device_lock include/linux/device.h:1030 [inline] uevent_show+0x17d/0x340 drivers/base/core.c:2730 dev_attr_show+0x55/0xc0 drivers/base/core.c:2424 sysfs_kf_seq_show+0x331/0x4c0 fs/sysfs/file.c:59 seq_read_iter+0x43f/0xd70 fs/seq_file.c:230 new_sync_read fs/read_write.c:484 [inline] vfs_read+0x975/0xb40 fs/read_write.c:565 ksys_read+0x18f/0x2b0 fs/read_write.c:708 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4610916b6a RSP: 002b:00007fff8cb76e38 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 000055fb81370810 RCX: 00007f4610916b6a RDX: 0000000000001000 RSI: 000055fb81347620 RDI: 0000000000000008 RBP: 000055fb81370810 R08: 0000000000000008 R09: 0000000000000000 R10: 000000000000010f R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000003fff R14: 00007fff8cb77318 R15: 000000000000000a Showing all locks held in the system: 1 lock held by ksoftirqd/0/17: #0: ffff8880b863e958 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:598 1 lock held by khungtaskd/31: #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline] #0: ffffffff8eb393e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6746 2 locks held by getty/5587: #0: ffff8880353120a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc90002fde2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x616/0x1770 drivers/tty/n_tty.c:2211 6 locks held by kworker/0:4/5856: #0: ffff888020ec8948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline] #0: ffff888020ec8948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x98b/0x18e0 kernel/workqueue.c:3319 #1: ffffc900041ffc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline] #1: ffffc900041ffc60 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9c6/0x18e0 kernel/workqueue.c:3319 #2: ffff888028821190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #2: ffff888028821190 (&dev->mutex){....}-{4:4}, at: hub_event+0x1fe/0x5150 drivers/usb/core/hub.c:5861 #3: ffff88807747e190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #3: ffff88807747e190 (&dev->mutex){....}-{4:4}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005 #4: ffff888035797160 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #4: ffff888035797160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x8e/0x520 drivers/base/dd.c:1005 #5: ffff888035795438 (&priv->cmd_lock){+.+.}-{4:4}, at: __pn533_send_async+0x270/0x680 drivers/nfc/pn533/pn533.c:458 4 locks held by udevd/6142: #0: ffff8880306d0b08 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xb4/0xd70 fs/seq_file.c:182 #1: ffff88807a2a1c88 (&of->mutex#2 ){+.+.}-{4:4}, at: kernfs_seq_start+0x53/0x3b0 fs/kernfs/file.c:154 #2: ffff8880336393c8 (kn->active#5){++++}-{0:0}, at: kernfs_seq_start+0x72/0x3b0 fs/kernfs/file.c:155 #3: ffff88807747e190 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:1030 [inline] #3: ffff88807747e190 (&dev->mutex){....}-{4:4}, at: uevent_show+0x17d/0x340 drivers/base/core.c:2730 ============================================= NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.14.0-rc7-syzkaller-00205-g586de92313fc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:236 [inline] watchdog+0x1058/0x10a0 kernel/hung_task.c:399 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:48 [inline] NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline] NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x21/0x30 drivers/acpi/processor_idle.c:111