INFO: task kworker/0:0:9 blocked for more than 143 seconds. Not tainted 6.16.0-rc7-syzkaller-ga83c371c4b6c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/0:0 state:R running task stack:20952 pid:9 tgid:9 ppid:2 task_flags:0x4208060 flags:0x00004000 Workqueue: events kernfs_notify_workfn Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x1325/0x3b10 kernel/sched/core.c:6786 __schedule_loop kernel/sched/core.c:6864 [inline] schedule+0xe7/0x3a0 kernel/sched/core.c:6879 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6936 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_notify_workfn+0xff/0xb30 fs/kernfs/file.c:915 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 INFO: task syz.5.1410:9656 blocked for more than 143 seconds. Not tainted 6.16.0-rc7-syzkaller-ga83c371c4b6c #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz.5.1410 state:D stack:28904 pid:9656 tgid:9655 ppid:3554 task_flags:0x400040 flags:0x00004004 Call Trace: context_switch kernel/sched/core.c:5397 [inline] __schedule+0x1325/0x3b10 kernel/sched/core.c:6786 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff890c8440 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline] (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x36/0x1c0 kernel/locking/lockdep.c:6770 5 locks held by kworker/1:2/1118: #0: ffff8881066f3548 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000192fd10 ( (work_completion)(&hub->events)){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810b3b4198 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:884 [inline] , at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898 #3: ffff888106ae0198 ( &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_activate fs/kernfs/dir.c:1425 [inline] , at: kernfs_add_one+0x349/0x840 fs/kernfs/dir.c:834 2 locks held by getty/2905: #0: ffff88811282a0a0 ( &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/3548: 1 lock held by syz-executor/3549: 1 lock held by syz-executor/3554: 1 lock held by syz-executor/3556: 1 lock held by syz-executor/3561: 3 locks held by kworker/1:3/5826: 4 locks held by udevd/5836: #0: ffff888115680540 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182 #1: ffff888114c0f088 (&of->mutex#2){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888112aa0698 (kn->active #9){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888106ae0198 ( &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/1:5/5981: 6 locks held by kworker/1:6/6103: #0: ffff8881066f3548 ( (wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x12a2/0x1b70 kernel/workqueue.c:3213 #1: ffffc9000463fd10 ((work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x929/0x1b70 kernel/workqueue.c:3214 #2: ffff88810bb14198 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:884 [inline] , at: hub_event+0x1be/0x5060 drivers/usb/core/hub.c:5898 #3: ffff888139cb6198 ( &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: ffffffff897bdb68 ( dev_pm_qos_sysfs_mtx){+.+.}-{4:4} , at: dev_pm_qos_constraints_destroy+0x28/0x780 drivers/base/power/qos.c:254 #5: ffff888100ac4988 ( &root->kernfs_rwsem){++++}-{4:4} , at: kernfs_find_and_get_ns+0x2f/0x70 fs/kernfs/dir.c:933 4 locks held by udevd/6410: #0: ffff8881141fd790 (&p->lock){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x12c0 fs/seq_file.c:182 #1: ffff888117d7c488 (&of->mutex #2 ){+.+.}-{4:4} , at: kernfs_seq_start+0x4d/0x240 fs/kernfs/file.c:154 #2: ffff888115876008 (kn->active#9){++++}-{0:0} , at: kernfs_seq_start+0x71/0x240 fs/kernfs/file.c:155 #3: ffff888117861198 ( &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/1:1/8680: 6 locks held by kworker/0:7/8847: 1 lock held by syz.6.1411/9658: 1 lock held by syz.2.1414/9664: 1 lock held by syz-executor/9665: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.16.0-rc7-syzkaller-ga83c371c4b6c #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+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 Sending NMI from CPU 0 to CPUs 1: imon 2-1:155.0: imon usb_rx_callback_intf0: status(-71): ignored NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 9665 Comm: syz-executor Not tainted 6.16.0-rc7-syzkaller-ga83c371c4b6c #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:410 Code: 1d a8 fe 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 1a 66 03 5d 40 89 da ec <5b> 0f b6 c0 5d 41 5c e9 8d 86 5c 04 e8 08 1e 05 ff eb a2 e8 91 1e RSP: 0000:ffffc900001a84a8 EFLAGS: 00000002 RAX: dffffc0000000060 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff82d57920 RDI: ffffffff9392af80 RBP: ffffffff9392af40 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000020 R14: fffffbfff2725642 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888269260000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc4bdb5fbc8 CR3: 0000000117e56000 CR4: 00000000003506f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:137 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:159 [inline] wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:2094 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3348 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3371 [inline] serial8250_console_write+0xf83/0x1890 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_warn+0xe4/0x120 drivers/base/core.c:4984 usb_rx_callback_intf0+0x11c/0x1a0 drivers/media/rc/imon.c:1768 __usb_hcd_giveback_urb+0x38d/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 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:mas_next_slot+0x130/0x21b0 lib/maple_tree.c:4697 Code: 8b 45 00 30 c0 48 39 c5 0f 84 cb 06 00 00 e8 97 a0 54 fa 48 8b 44 24 50 48 b9 00 00 00 00 00 fc ff df 48 c1 e8 03 80 3c 08 00 <0f> 85 bb 1c 00 00 4c 89 f8 4c 89 fa 49 8b 5d 28 48 b9 00 00 00 00 RSP: 0000:ffffc90001caf790 EFLAGS: 00000246 RAX: 1ffff92000395f4d RBX: 0000000000000000 RCX: dffffc0000000000 RDX: ffff888118d11d00 RSI: ffffffff8728f609 RDI: 0000000000000005 RBP: ffff88810a7fac00 R08: 0000000000000005 R09: 0000000000000002 R10: 0000000000000000 R11: 0000000000000001 R12: fffffffffffffffe R13: ffffc90001cafa40 R14: dffffc0000000000 R15: ffffc90001cafa7d mas_find+0x2c6/0x530 lib/maple_tree.c:6048 unmap_vmas+0x25b/0x470 mm/memory.c:1988 exit_mmap+0x1b9/0xb90 mm/mmap.c:1284 __mmput kernel/fork.c:1121 [inline] mmput+0xdb/0x430 kernel/fork.c:1144 exit_mm kernel/exit.c:581 [inline] do_exit+0x7c4/0x2bd0 kernel/exit.c:952 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: 0033:0x7f3088f8d291 Code: Unable to access opcode bytes at 0x7f3088f8d267. RSP: 002b:00007ffd52eb3460 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: 0000000000000003 RBX: 0000000000000002 RCX: 00007f3088f8d291 RDX: 0000000000000002 RSI: 00007f3089010e0e RDI: 00000000ffffff9c RBP: 00007f3089010e0e R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 0000000000000003 R14: 0000000000000009 R15: 0000000000000000