INFO: task jbd2/sda1-8:2823 blocked for more than 143 seconds. Not tainted syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:jbd2/sda1-8 state:D stack:24456 pid:2823 tgid:2823 ppid:2 task_flags:0x240040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5260 [inline] __schedule+0xeb0/0x3e50 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 io_schedule+0x8a/0xf0 kernel/sched/core.c:7791 bit_wait_io+0xd/0xe0 kernel/sched/wait_bit.c:250 __wait_on_bit+0x65/0x180 kernel/sched/wait_bit.c:52 out_of_line_wait_on_bit+0xdc/0x110 kernel/sched/wait_bit.c:67 wait_on_bit_io include/linux/wait_bit.h:105 [inline] __wait_on_buffer+0x64/0x70 fs/buffer.c:123 wait_on_buffer include/linux/buffer_head.h:420 [inline] journal_wait_on_commit_record fs/jbd2/commit.c:171 [inline] jbd2_journal_commit_transaction+0x4851/0x6680 fs/jbd2/commit.c:881 kjournald2+0x200/0x760 fs/jbd2/journal.c:201 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Showing all locks held in the system: 1 lock held by khungtaskd/30: #0: ffffffff894da3a0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] #0: ffffffff894da3a0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:867 [inline] #0: ffffffff894da3a0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 5 locks held by kworker/1:1/37: 1 lock held by udevd/2861: #0: ffff888100ac5988 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185 2 locks held by getty/2923: #0: ffff88811277a0a0 ( &tty->ldisc_sem){++++}-{0:0} , at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243 #1: ffffc900000452f0 (&ldata->atomic_read_lock ){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/2969: #0: ffff888100ac5988 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167 1 lock held by syz-executor/2970: #0: ffff888100ac5988 (&root->kernfs_rwsem){++++}-{4:4}, at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167 1 lock held by syz-executor/2973: 1 lock held by syz-executor/2974: #0: ffff888100ac5988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0x397/0x740 fs/kernfs/dir.c:1167 1 lock held by syz-executor/2975: 4 locks held by udevd/5228: #0: ffff88813448c9e0 ( &p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:182 #1: ffff88811c0cd888 (&of->mutex){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff88813405c2d8 (kn->active #9){++++}-{0:0} , at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] , at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88811a65e198 (&dev->mutex){....}-{4:4}, at: device_lock_interruptible include/linux/device.h:900 [inline] ffff88811a65e198 (&dev->mutex){....}-{4:4}, at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 4 locks held by kworker/1:4/5235: 6 locks held by kworker/1:5/5280: #0: ffff888105eb4548 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90002b4fca8 ((work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffff88810a3db198 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88812072c198 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1006 #4: ffff8881247e3160 ( &dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1006 #5: ffffffff8a2e0f48 (input_mutex ){+.+.}-{4:4} , at: class_mutex_intr_constructor include/linux/mutex.h:255 [inline] , at: input_register_device.cold+0x5b/0x375 drivers/input/input.c:2374 7 locks held by kworker/1:6/5370: #0: ffff888105eb4548 ((wq_completion)usb_hub_wq ){+.+.}-{0:0} , at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90003cc7ca8 ((work_completion)(&hub->events) ){+.+.}-{0:0} , at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 #2: ffff88810a3c3198 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899 #3: ffff88811a65e198 (&dev->mutex){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1006 #4: ffff8881170ab160 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_attach+0x7e/0x4d0 drivers/base/dd.c:1006 #5: ffffffff8a2e0f48 ( input_mutex ){+.+.}-{4:4} , at: class_mutex_intr_constructor include/linux/mutex.h:255 [inline] , at: input_register_device.cold+0x5b/0x375 drivers/input/input.c:2374 #6: ffff888100ac5988 (&root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_add_one+0x38/0x850 fs/kernfs/dir.c:796 4 locks held by udevd/6605: #0: ffff888133f94d58 (&p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:182 #1: ffff88811205f088 (&of->mutex ){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888133294e18 (kn->active #9){++++}-{0:0} , at: kernfs_get_active_of fs/kernfs/file.c:80 [inline] , at: kernfs_seq_start+0xbc/0x2a0 fs/kernfs/file.c:173 #3: ffff88812072c198 (&dev->mutex ){....}-{4:4} , at: device_lock_interruptible include/linux/device.h:900 [inline] , at: manufacturer_show+0x26/0xa0 drivers/usb/core/sysfs.c:142 1 lock held by syz.1.625/7394: #0: ffff888100ac5988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_remove_by_name_ns+0x3d/0xf0 fs/kernfs/dir.c:1717 1 lock held by cmp/7415: #0: ffff888100ac5988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_dop_revalidate+0xa5/0x740 fs/kernfs/dir.c:1185 1 lock held by syz.4.629/7417: 2 locks held by syz.2.630/7419: #0: ffff888109fc4dc0 (&dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_driver_lock drivers/base/dd.c:1104 [inline] , at: __driver_attach+0x20c/0x5c0 drivers/base/dd.c:1224 #1: ffff888100ac5988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_remove_by_name_ns+0x3d/0xf0 fs/kernfs/dir.c:1717 2 locks held by syz.0.631/7421: #0: ffff8881067b4dc0 ( &dev->mutex ){....}-{4:4} , at: device_lock include/linux/device.h:895 [inline] , at: __device_driver_lock drivers/base/dd.c:1104 [inline] , at: __driver_attach+0x20c/0x5c0 drivers/base/dd.c:1224 #1: ffff888100ac5988 ( &root->kernfs_rwsem ){++++}-{4:4} , at: kernfs_remove_by_name_ns+0x3d/0xf0 fs/kernfs/dir.c:1717 1 lock held by syz.3.632/7424: ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 nmi_cpu_backtrace.cold+0x12d/0x151 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x1d7/0x230 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:161 [inline] __sys_info lib/sys_info.c:157 [inline] sys_info+0x141/0x190 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xcc3/0xfe0 kernel/hung_task.c:515 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Sending NMI from CPU 0 to CPUs 1: yealink 3-1:36.0: urb_irq_callback - urb status -71 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 1121 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events dvb_usb_read_remote_control RIP: 0010:io_serial_in+0x87/0xb0 drivers/tty/serial/8250/8250_port.c:401 Code: 7b 9f 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 c3 cc cc cc cc e8 18 6a 01 ff eb a2 e8 a1 6a RSP: 0018:ffffc900001a83f8 EFLAGS: 00000002 RAX: dffffc0000000060 RBX: 00000000000003fd RCX: 0000000000000000 RDX: 00000000000003fd RSI: ffffffff8311c0c0 RDI: ffffffff93f14fc0 RBP: ffffffff93f14f80 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000020 R14: fffffbfff27e2a4a R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fffb81de548 CR3: 0000000110290000 CR4: 00000000003506f0 Call Trace: serial_in drivers/tty/serial/8250/8250.h:128 [inline] serial_lsr_in drivers/tty/serial/8250/8250.h:150 [inline] wait_for_lsr+0x13a/0x210 drivers/tty/serial/8250/8250_port.c:1961 fifo_wait_for_lsr drivers/tty/serial/8250/8250_port.c:3234 [inline] serial8250_console_fifo_write drivers/tty/serial/8250/8250_port.c:3257 [inline] serial8250_console_write+0xdb9/0x1900 drivers/tty/serial/8250/8250_port.c:3342 console_emit_next_record kernel/printk/printk.c:3129 [inline] console_flush_one_record+0x790/0xe50 kernel/printk/printk.c:3215 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 dev_vprintk_emit+0x394/0x3e0 drivers/base/core.c:4914 dev_printk_emit+0xd2/0x10d drivers/base/core.c:4925 __dev_printk+0xcb/0x100 drivers/base/core.c:4937 _dev_err+0xef/0x127 drivers/base/core.c:4980 urb_irq_callback.cold+0x41/0xfd drivers/input/misc/yealink.c:418 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741 dummy_timer+0xd85/0x3670 drivers/usb/gadget/udc/dummy_hcd.c:1995 __run_hrtimer kernel/time/hrtimer.c:1777 [inline] __hrtimer_run_queues+0x516/0x990 kernel/time/hrtimer.c:1841 hrtimer_run_softirq+0x17d/0x350 kernel/time/hrtimer.c:1858 handle_softirqs+0x1dd/0x8f0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0xed/0x150 kernel/softirq.c:723 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0x8f/0xb0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_flush_one_record+0xac3/0xe50 kernel/printk/printk.c:3216 Code: 00 e8 11 59 28 00 9c 5d 81 e5 00 02 00 00 31 ff 48 89 ee e8 5f 76 20 00 48 85 ed 0f 85 d7 01 00 00 e8 71 7b 20 00 fb 4c 89 e8 <48> c1 e8 03 42 80 3c 38 00 0f 85 64 03 00 00 48 8b 0c 24 48 8b 6b RSP: 0018:ffffc90001b8f820 EFLAGS: 00000293 RAX: ffffffff89a50638 RBX: ffffffff89a505e0 RCX: ffffffff8190c081 RDX: ffff88810eb29d40 RSI: ffffffff8190c08f RDI: ffff88810eb29d40 RBP: 0000000000000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000b503 R13: ffffffff89a50638 R14: ffffc90001b8f8a0 R15: dffffc0000000000 console_flush_all kernel/printk/printk.c:3289 [inline] __console_flush_and_unlock kernel/printk/printk.c:3319 [inline] console_unlock+0x103/0x260 kernel/printk/printk.c:3359 vprintk_emit+0x407/0x6b0 kernel/printk/printk.c:2426 _printk+0xcf/0x110 kernel/printk/printk.c:2451 m920x_read drivers/media/usb/dvb-usb/m920x.c:40 [inline] m920x_rc_core_query.cold+0x13/0x30 drivers/media/usb/dvb-usb/m920x.c:226 dvb_usb_read_remote_control+0xdd/0x1b0 drivers/media/usb/dvb-usb/dvb-usb-remote.c:261 process_one_work+0x9c2/0x1840 kernel/workqueue.c:3257 process_scheduled_works kernel/workqueue.c:3340 [inline] worker_thread+0x5da/0xe40 kernel/workqueue.c:3421 kthread+0x3b3/0x730 kernel/kthread.c:463 ret_from_fork+0x6c3/0xa20 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246