INFO: task kworker/u4:0:9 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:0 state:D stack:26288 pid:9 ppid:2 flags:0x00004000 Workqueue: events_unbound fsnotify_mark_destroy_workfn Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x2c7/0x5a0 kernel/sched/completion.c:138 __synchronize_srcu+0x2b9/0x350 kernel/rcu/srcutree.c:1243 fsnotify_mark_destroy_workfn+0x106/0x2f0 fs/notify/mark.c:924 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task kworker/u4:5:4371 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u4:5 state:D stack:26352 pid:4371 ppid:2 flags:0x00004000 Workqueue: events_unbound fsnotify_connector_destroy_workfn Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:2144 do_wait_for_common kernel/sched/completion.c:85 [inline] __wait_for_common kernel/sched/completion.c:106 [inline] wait_for_common kernel/sched/completion.c:117 [inline] wait_for_completion+0x2c7/0x5a0 kernel/sched/completion.c:138 __synchronize_srcu+0x2b9/0x350 kernel/rcu/srcutree.c:1243 fsnotify_connector_destroy_workfn+0x40/0xa0 fs/notify/mark.c:234 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 INFO: task udevd:4390 blocked for more than 144 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:udevd state:D stack:26992 pid:4390 ppid:3637 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562 schedule+0xb9/0x180 kernel/sched/core.c:6638 schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6697 __mutex_lock_common kernel/locking/mutex.c:679 [inline] __mutex_lock+0x562/0xaf0 kernel/locking/mutex.c:747 device_lock include/linux/device.h:840 [inline] uevent_show+0x16c/0x320 drivers/base/core.c:2669 dev_attr_show+0x50/0xb0 drivers/base/core.c:2372 sysfs_kf_seq_show+0x349/0x4b0 fs/sysfs/file.c:59 seq_read_iter+0x49b/0xd50 fs/seq_file.c:230 call_read_iter include/linux/fs.h:2259 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x4a7/0xa00 fs/read_write.c:470 ksys_read+0x14c/0x250 fs/read_write.c:613 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fa9b11d9407 RSP: 002b:00007ffcf7397850 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 RAX: ffffffffffffffda RBX: 00007fa9b114d880 RCX: 00007fa9b11d9407 RDX: 0000000000001000 RSI: 00005599de813a00 RDI: 0000000000000008 RBP: 00007fa9b1321ff0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 000000000000000a R13: 00007fa9b1321ea0 R14: 0000000000000000 R15: 00005599de82b610 Showing all locks held in the system: 2 locks held by kworker/u4:0/9: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc900000e7d00 ((reaper_work).work){+.+.}-{0:0}, at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 1 lock held by rcu_tasks_kthre/12: #0: ffffffff8cb2df70 ( rcu_tasks.tasks_gp_mutex ){+.+.}-{3:3} , at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by rcu_tasks_trace/13: #0: ffffffff8cb2e790 (rcu_tasks_trace.tasks_gp_mutex ){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x33/0xf00 kernel/rcu/tasks.h:517 1 lock held by khungtaskd/28: #0: ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline] ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline] ffffffff8cb2d5e0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6513 1 lock held by klogd/3626: 2 locks held by getty/4025: #0: ffff88814d1cc098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244 #1: ffffc9000327b2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x429/0x1390 drivers/tty/n_tty.c:2198 7 locks held by kworker/0:8/4325: 2 locks held by kworker/u4:5/4371: #0: ffff888017479138 ((wq_completion)events_unbound){+.+.}-{0:0} , at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 #1: ffffc90003267d00 ( connector_reaper_work ){+.+.}-{0:0} , at: process_one_work+0x7b0/0x1160 kernel/workqueue.c:2267 4 locks held by udevd/4390: #0: ffff88802a005418 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xad/0xd50 fs/seq_file.c:182 #1: ffff888077549888 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x58/0x410 fs/kernfs/file.c:172 #2: ffff888025880a00 (kn->active#5){.+.+}-{0:0}, at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] #2: ffff888025880a00 (kn->active#5){.+.+}-{0:0}, at: kernfs_seq_start+0xae/0x410 fs/kernfs/file.c:173 #3: ffff888079a1c190 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:840 [inline] #3: ffff888079a1c190 (&dev->mutex){....}-{3:3}, at: uevent_show+0x16c/0x320 drivers/base/core.c:2669 2 locks held by dhcpcd/4489: #0: ffff8880787f0130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1805 [inline] #0: ffff8880787f0130 (sk_lock-AF_PACKET){+.+.}-{0:0}, at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249 #1: ffffffff8cb332b8 ( rcu_state.exp_mutex ){+.+.}-{3:3} , at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline] , at: synchronize_rcu_expedited+0x2ec/0x890 kernel/rcu/tree_exp.h:962 2 locks held by dhcpcd/4490: #0: ffff8880787f2130 ( sk_lock-AF_PACKET ){+.+.}-{0:0} , at: lock_sock include/net/sock.h:1805 [inline] , at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249 #1: ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline] ffffffff8cb332b8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x3c0/0x890 kernel/rcu/tree_exp.h:962 1 lock held by dhcpcd/4491: #0: ffff8880769d0130 ( sk_lock-AF_PACKET ){+.+.}-{0:0} , at: lock_sock include/net/sock.h:1805 [inline] , at: packet_do_bind+0x32/0xce0 net/packet/af_packet.c:3249 ============================================= NMI backtrace for cpu 1 CPU: 1 PID: 28 Comm: khungtaskd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 nmi_cpu_backtrace+0x3e6/0x460 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x1d4/0x450 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline] watchdog+0xeee/0xf30 kernel/hung_task.c:377 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4325 Comm: kworker/0:8 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Workqueue: usb_hub_wq hub_event RIP: 0010:bytes_is_nonzero mm/kasan/generic.c:84 [inline] RIP: 0010:memory_is_nonzero mm/kasan/generic.c:102 [inline] RIP: 0010:memory_is_poisoned_n mm/kasan/generic.c:128 [inline] RIP: 0010:memory_is_poisoned mm/kasan/generic.c:159 [inline] RIP: 0010:check_region_inline mm/kasan/generic.c:180 [inline] RIP: 0010:kasan_check_range+0x92/0x290 mm/kasan/generic.c:189 Code: 49 83 ff 10 7f 29 4d 85 ff 0f 84 38 01 00 00 4c 89 cb 48 f7 d3 4c 01 f3 41 80 3b 00 0f 85 86 01 00 00 49 ff c3 48 ff c3 75 ee 18 01 00 00 44 89 dd 83 e5 07 0f 84 b5 00 00 00 41 80 3b 00 4d RSP: 0018:ffffc90000007910 EFLAGS: 00000056 RAX: 0000000000000001 RBX: 0000000000000000 RCX: ffffffff8164f804 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff90af9248 RBP: 0000000000000008 R08: ffffffff90af924f R09: 1ffffffff215f249 R10: dffffc0000000000 R11: fffffbfff215f24a R12: dffffc0000000001 R13: dffffc0000000000 R14: 1ffffffff215f249 R15: 0000000000000001 FS: 0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000556cf803c248 CR3: 000000007e44e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: instrument_atomic_read include/linux/instrumented.h:72 [inline] _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline] hlock_class kernel/locking/lockdep.c:228 [inline] mark_lock+0x94/0x320 kernel/locking/lockdep.c:4606 mark_usage kernel/locking/lockdep.c:4549 [inline] __lock_acquire+0xd7e/0x7d10 kernel/locking/lockdep.c:5003 lock_acquire+0x1bb/0x4a0 kernel/locking/lockdep.c:5662 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xb0/0x100 kernel/locking/spinlock.c:162 hrtimer_run_softirq+0x6c/0x2a0 kernel/time/hrtimer.c:1825 handle_softirqs+0x2a1/0x930 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:1948 [inline] RIP: 0010:vprintk_emit+0x48b/0x6a0 kernel/printk/printk.c:2302 Code: 86 01 00 00 e8 46 0b 1b 00 41 89 df 4d 85 f6 48 8b 5c 24 08 75 07 e8 34 0b 1b 00 eb 06 e8 2d 0b 1b 00 fb 48 c7 c7 80 18 b2 8c <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 0d d2 RSP: 0018:ffffc90003f463e0 EFLAGS: 00000293 RAX: ffffffff81676a23 RBX: ffffffff816768b5 RCX: ffff88802f343b80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8cb21880 RBP: ffffc90003f464d0 R08: ffffffff90af9357 R09: 1ffffffff215f26a R10: dffffc0000000000 R11: fffffbfff215f26b R12: dffffc0000000000 R13: 1ffff920007e8c80 R14: 0000000000000200 R15: 000000000000001b dev_vprintk_emit+0x34e/0x400 drivers/base/core.c:4933 dev_printk_emit+0xeb/0x139 drivers/base/core.c:4944 _dev_err+0x11b/0x16c drivers/base/core.c:4999 parse_uac2_sample_rate_range+0x992/0xc60 sound/usb/format.c:401 parse_audio_format_rates_v2v3+0x3c7/0x16c0 sound/usb/format.c:636 parse_audio_format_i+0x74c/0xe80 sound/usb/format.c:718 snd_usb_parse_audio_format+0x87/0x740 sound/usb/format.c:796 snd_usb_get_audioformat_uac12 sound/usb/stream.c:854 [inline] __snd_usb_parse_audio_interface+0x18b1/0x4b00 sound/usb/stream.c:1196 snd_usb_parse_audio_interface+0x36/0xb0 sound/usb/stream.c:1274 create_standard_audio_quirk+0x59/0x120 sound/usb/quirks.c:100 snd_usb_create_quirk sound/usb/quirks.c:539 [inline] create_composite_quirk+0x1ec/0x4e0 sound/usb/quirks.c:48 usb_audio_probe+0xb97/0x1d90 sound/usb/card.c:885 usb_probe_interface+0x5c5/0xb20 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2aa/0xc70 drivers/base/dd.c:639 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3697 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2223 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238 usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2aa/0xc70 drivers/base/dd.c:639 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3697 usb_new_device+0xd66/0x1650 drivers/usb/core/hub.c:2659 hub_port_connect drivers/usb/core/hub.c:5517 [inline] hub_port_connect_change drivers/usb/core/hub.c:5657 [inline] port_event drivers/usb/core/hub.c:5817 [inline] hub_event+0x2dcf/0x5560 drivers/usb/core/hub.c:5899 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295