INFO: task jbd2/sda1-8:2820 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:26600 pid:2820 tgid:2820 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: 2 locks held by kworker/u8:0/12: #0: ffff888100089148 ( (wq_completion)events_unbound #2 ){+.+.}-{0:0} , at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc900000cfca8 ((work_completion)(&sub_info->work) ){+.+.}-{0:0} , at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 5 locks held by kworker/1:0/23: 1 lock held by khungtaskd/30: #0: ffffffff894da3a0 (rcu_read_lock ){....}-{1:3} , at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline] , at: rcu_read_lock include/linux/rcupdate.h:867 [inline] , at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775 8 locks held by kworker/1:1/37: 2 locks held by kworker/u8:2/38: #0: ffff888100089148 ((wq_completion)events_unbound #2 ){+.+.}-{0:0} , at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90000287ca8 ( (work_completion)(&sub_info->work)){+.+.}-{0:0} , at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 2 locks held by kworker/u8:4/51: #0: ffff888100089148 ( (wq_completion)events_unbound #2 ){+.+.}-{0:0} , at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc90000557ca8 ((work_completion)(&sub_info->work) ){+.+.}-{0:0} , at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 2 locks held by kworker/u8:5/172: #0: ffff888100089148 ((wq_completion)events_unbound #2 ){+.+.}-{0:0} , at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc9000155fca8 ( (work_completion)(&sub_info->work) ){+.+.}-{0:0}, at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 2 locks held by kworker/u8:9/479: #0: ffff888100089148 ( (wq_completion)events_unbound#2 ){+.+.}-{0:0} , at: process_one_work+0x11ae/0x1840 kernel/workqueue.c:3232 #1: ffffc9000198fca8 ( (work_completion)(&sub_info->work) ){+.+.}-{0:0} , at: process_one_work+0x927/0x1840 kernel/workqueue.c:3233 5 locks held by kworker/1:2/1122: 2 locks held by getty/2920: #0: ffff888108a970a0 ( &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 4 locks held by kworker/1:3/5202: 4 locks held by udevd/5248: #0: ffff888134e24e80 (&p->lock ){+.+.}-{4:4} , at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:182 #1: ffff888125705488 ( &of->mutex #2){+.+.}-{4:4} , at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172 #2: ffff888135327698 (kn->active #19 ){++++}-{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: ffff888108bb8198 (&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 6 locks held by kworker/1:4/5270: 7 locks held by kworker/1:5/5304: 3 locks held by syz.1.335/5959: #0: ffff888111a5a118 (&evdev->mutex ){+.+.}-{4:4} , at: evdev_close_device drivers/input/evdev.c:402 [inline] , at: evdev_release+0x29e/0x420 drivers/input/evdev.c:447 #1: ffff88810fbd62c0 ( &dev->mutex #2){+.+.}-{4:4} , at: class_mutex_constructor include/linux/mutex.h:253 [inline] , at: input_close_device+0x46/0x2b0 drivers/input/input.c:646 #2: ffffffff894e6b78 (rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 1 lock held by syz.0.341/5971: #0: ffffffff894e6b78 ( rcu_state.exp_mutex ){+.+.}-{4:4} , at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343 1 lock held by modprobe/8634: 1 lock held by modprobe/8638: ============================================= 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 2-1:36.0: urb_irq_callback - urb status -71 NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 37 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT(voluntary) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Workqueue: events_power_efficient do_cache_clean RIP: 0010:io_serial_out+0x8f/0xb0 drivers/tty/serial/8250/8250_port.c:407 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 d1 6a 01 ff eb a0 e8 5a 6b 01 RSP: 0018:ffffc900001a8430 EFLAGS: 00000006 RAX: 0000000000000000 RBX: 00000000000003f9 RCX: 0000000000000000 RDX: 00000000000003f9 RSI: ffffffff8311c005 RDI: ffffffff93f14fc0 RBP: ffffffff93f14f80 R08: 0000000000000001 R09: 000000000000001f R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: ffffffff93f14fd0 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff888268a6a000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fc243e540c0 CR3: 00000000092a8000 CR4: 00000000003506f0 Call Trace: serial_out drivers/tty/serial/8250/8250.h:133 [inline] serial8250_clear_IER+0xa7/0xd0 drivers/tty/serial/8250/8250_port.c:714 serial8250_console_write+0x252/0x1900 drivers/tty/serial/8250/8250_port.c:3307 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:lock_acquire+0x5e/0x330 kernel/locking/lockdep.c:5872 Code: 05 7b 34 3d 0b 83 f8 07 0f 87 a4 02 00 00 48 0f a3 05 06 a8 3e 09 0f 82 6f 02 00 00 8b 35 9e b4 3e 09 85 f6 0f 85 8a 00 00 00 <48> 8b 44 24 30 65 48 2b 05 1d 34 3d 0b 0f 85 b8 02 00 00 48 83 c4 RSP: 0018:ffffc90000277aa0 EFLAGS: 00000206 RAX: 0000000000000046 RBX: 0000000000000000 RCX: 0000000000000002 RDX: 0000000000000000 RSI: ffffffff88dcb9c1 RDI: ffffffff878e97a0 RBP: ffffffff8aa4ed58 R08: 000000006c1b8a05 R09: 0000000000000207 R10: 0000000000000200 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000000 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline] _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154 spin_lock include/linux/spinlock.h:351 [inline] cache_clean+0x71/0x9b0 net/sunrpc/cache.c:444 do_cache_clean net/sunrpc/cache.c:520 [inline] do_cache_clean+0x29/0xb0 net/sunrpc/cache.c:513 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