INFO: task kworker/u8:31:15351 blocked for more than 143 seconds. Tainted: G L syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:kworker/u8:31 state:D stack:25560 pid:15351 tgid:15351 ppid:2 task_flags:0x4208060 flags:0x00080000 Workqueue: writeback wb_workfn (flush-7:6) Call Trace: context_switch kernel/sched/core.c:5295 [inline] __schedule+0x1585/0x5340 kernel/sched/core.c:6907 __schedule_loop kernel/sched/core.c:6989 [inline] schedule+0x164/0x360 kernel/sched/core.c:7004 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:7061 __mutex_lock_common kernel/locking/mutex.c:692 [inline] __mutex_lock+0x7fe/0x1300 kernel/locking/mutex.c:776 jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 jfs_write_inode+0x145/0x220 fs/jfs/inode.c:138 write_inode fs/fs-writeback.c:1583 [inline] __writeback_single_inode+0x75a/0x11a0 fs/fs-writeback.c:1814 writeback_sb_inodes+0x992/0x1a20 fs/fs-writeback.c:2043 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2119 wb_writeback+0x46a/0xb70 fs/fs-writeback.c:2230 wb_check_old_data_flush fs/fs-writeback.c:2334 [inline] wb_do_writeback fs/fs-writeback.c:2387 [inline] wb_workfn+0xb4c/0xf50 fs/fs-writeback.c:2415 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Showing all locks held in the system: 1 lock held by khungtaskd/31: #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:850 [inline] #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775 2 locks held by getty/5588: #0: ffff8880343d30a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243 #1: ffffc9000332b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0 drivers/tty/n_tty.c:2211 1 lock held by syz-executor/5833: 1 lock held by udevd/6507: 2 locks held by kworker/u8:14/10369: #0: ffff8880b863ade0 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0xb6/0x150 kernel/sched/core.c:655 #1: ffff8880b8624588 (psi_seq){-.-.}-{0:0}, at: psi_task_switch+0x53/0x880 kernel/sched/psi.c:933 4 locks held by syz.6.2146/15114: 4 locks held by kworker/u8:31/15351: #0: ffff888020ab8148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x855/0x1650 kernel/workqueue.c:3254 #1: ffffc9000babfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x87c/0x1650 kernel/workqueue.c:3255 #2: ffff8880366360e0 (&type->s_umount_key#64){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:565 #3: ffff888041ca1418 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:108 ============================================= NMI backtrace for cpu 0 CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 nmi_cpu_backtrace+0x274/0x2d0 lib/nmi_backtrace.c:113 nmi_trigger_cpumask_backtrace+0x17a/0x300 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+0x135/0x170 lib/sys_info.c:165 check_hung_uninterruptible_tasks kernel/hung_task.c:346 [inline] watchdog+0xfd9/0x1030 kernel/hung_task.c:515 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 UID: 0 PID: 10369 Comm: kworker/u8:14 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Workqueue: bond3 bond_mii_monitor RIP: 0010:___update_load_sum kernel/sched/pelt.c:-1 [inline] RIP: 0010:update_irq_load_avg+0x3e0/0xf10 kernel/sched/pelt.c:458 Code: 00 49 bd 00 fc ff ff ff ff ff 7f 4d 21 e5 49 01 c5 48 b8 00 00 00 00 00 fc ff df 41 80 3c 07 00 74 08 4c 89 f7 e8 c0 83 94 00 <49> c1 ec 0a 4c 89 ab 80 0c 00 00 4c 8d b3 9c 0c 00 00 4c 89 f2 48 RSP: 0018:ffffc90000a08b68 EFLAGS: 00000046 RAX: dffffc0000000000 RBX: ffff8880b873ad80 RCX: 0000000000000000 RDX: 0000000000000100 RSI: 000000000000250d RDI: ffff8880b873b8d0 RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200014116c R12: 00000000000026e0 R13: 000000e13cf8c800 R14: ffff8880b873ba00 R15: 1ffff110170e7740 FS: 0000000000000000(0000) GS:ffff888125555000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f3a88d456b8 CR3: 0000000075ec6000 CR4: 00000000003526f0 Call Trace: update_rq_clock_task kernel/sched/core.c:840 [inline] update_rq_clock+0x25e/0x570 kernel/sched/core.c:867 ttwu_queue kernel/sched/core.c:3917 [inline] try_to_wake_up+0x710/0x1390 kernel/sched/core.c:4242 call_timer_fn+0x192/0x640 kernel/time/timer.c:1748 expire_timers kernel/time/timer.c:1799 [inline] __run_timers kernel/time/timer.c:2373 [inline] __run_timer_base+0x652/0x8b0 kernel/time/timer.c:2385 run_timer_base kernel/time/timer.c:2394 [inline] run_timer_softirq+0xb7/0x170 kernel/time/timer.c:2404 handle_softirqs+0x22a/0x870 kernel/softirq.c:626 __do_softirq kernel/softirq.c:660 [inline] invoke_softirq kernel/softirq.c:496 [inline] __irq_exit_rcu+0x5f/0x150 kernel/softirq.c:727 irq_exit_rcu+0x9/0x30 kernel/softirq.c:743 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline] sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1056 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2039 [inline] RIP: 0010:vprintk_emit+0x45d/0x560 kernel/printk/printk.c:2478 Code: 0f 84 44 ff ff ff e8 b2 2c 21 00 fb eb 44 e8 aa 2c 21 00 e8 e5 5b 0b 0a 4d 85 f6 74 94 e8 9b 2c 21 00 fb 48 c7 c7 20 27 75 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 16 RSP: 0018:ffffc9000bf475e0 EFLAGS: 00000293 RAX: ffffffff81a476b5 RBX: ffffffff81a4752f RCX: ffff888079648000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e752720 RBP: ffffc9000bf47690 R08: ffffffff9011c5b7 R09: 1ffffffff20238b6 R10: dffffc0000000000 R11: fffffbfff20238b7 R12: 0000000000000000 R13: 0000000000000035 R14: 0000000000000200 R15: 1ffff920017e8ec0 _printk+0xdd/0x130 kernel/printk/printk.c:2504 netdev_warn+0x11e/0x180 net/core/dev.c:12995 bond_miimon_commit drivers/net/bonding/bond_main.c:2750 [inline] bond_mii_monitor+0x1a3a/0x2ec0 drivers/net/bonding/bond_main.c:2857 process_one_work+0x949/0x1650 kernel/workqueue.c:3279 process_scheduled_works kernel/workqueue.c:3362 [inline] worker_thread+0xb46/0x1140 kernel/workqueue.c:3443 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245