INFO: task kworker/u8:3:49 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc3-syzkaller-00072-gee88bddf7f2f #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:3    state:D stack:19720 pid:49    tgid:49    ppid:2      task_flags:0x4208160 flags:0x00004000
Workqueue: writeback wb_workfn (flush-7:1)
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5396 [inline]
 __schedule+0x16a2/0x4cb0 kernel/sched/core.c:6785
 __schedule_loop kernel/sched/core.c:6863 [inline]
 schedule+0x165/0x360 kernel/sched/core.c:6878
 schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6935
 __mutex_lock_common kernel/locking/mutex.c:679 [inline]
 __mutex_lock+0x724/0xe80 kernel/locking/mutex.c:747
 jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
 jfs_write_inode+0x145/0x220 fs/jfs/inode.c:132
 write_inode fs/fs-writeback.c:1525 [inline]
 __writeback_single_inode+0x6f1/0xff0 fs/fs-writeback.c:1745
 writeback_sb_inodes+0x6b5/0x1000 fs/fs-writeback.c:1976
 __writeback_inodes_wb+0x111/0x240 fs/fs-writeback.c:2047
 wb_writeback+0x44f/0xaf0 fs/fs-writeback.c:2158
 wb_check_old_data_flush fs/fs-writeback.c:2262 [inline]
 wb_do_writeback fs/fs-writeback.c:2315 [inline]
 wb_workfn+0xaef/0xef0 fs/fs-writeback.c:2343
 process_one_work kernel/workqueue.c:3238 [inline]
 process_scheduled_works+0xade/0x17b0 kernel/workqueue.c:3321
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3402
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
1 lock held by pool_workqueue_/3:
 #0: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 #0: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
3 locks held by kworker/u8:0/12:
 #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801a489148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc90000117bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90000117bc0 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffffffff8f4fdc48 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
1 lock held by kauditd/30:
 #0: ffff8880b8639e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
1 lock held by khungtaskd/31:
 #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8e13ee60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6770
4 locks held by kworker/u8:3/49:
 #0: ffff88801fea2148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801fea2148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc90000b97bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc90000b97bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffff88814bbce0e0 (&type->s_umount_key#86){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0 fs/super.c:563
 #3: ffff888059723918 (&jfs_ip->commit_mutex){+.+.}-{4:4}, at: jfs_commit_inode+0x1ca/0x530 fs/jfs/inode.c:102
2 locks held by dhcpcd/5484:
 #0: ffff88802f9896d0 (nlk_cb_mutex-ROUTE){+.+.}-{4:4}, at: __netlink_dump_start+0xfe/0x7e0 net/netlink/af_netlink.c:2388
 #1: ffffffff8f4fdc48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f4fdc48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_dumpit+0x92/0x200 net/core/rtnetlink.c:6812
2 locks held by getty/5582:
 #0: ffff888034f0a0a0 (&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+0x43e/0x1400 drivers/tty/n_tty.c:2222
1 lock held by syz-executor/6547:
 #0: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 #0: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
5 locks held by kworker/u8:9/6864:
 #0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
 #0: ffff88801b2fb948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0 kernel/workqueue.c:3321
 #1: ffffc9000481fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
 #1: ffffc9000481fbc0 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0 kernel/workqueue.c:3321
 #2: ffffffff8f4f1050 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xf7/0x800 net/core/net_namespace.c:662
 #3: ffffffff8f4fdc48 (rtnl_mutex){+.+.}-{4:4}, at: default_device_exit_batch+0xdc/0x890 net/core/dev.c:12630
 #4: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:336 [inline]
 #4: ffffffff8e144978 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x3b9/0x730 kernel/rcu/tree_exp.h:998
4 locks held by syz.1.159/7342:
2 locks held by syz.3.289/8454:
 #0: ffff88814bbce0e0 (&type->s_umount_key#86){++++}-{4:4}, at: __super_lock fs/super.c:59 [inline]
 #0: ffff88814bbce0e0 (&type->s_umount_key#86){++++}-{4:4}, at: super_lock+0x2a9/0x3b0 fs/super.c:121
 #1: ffff888024da47d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:387 [inline]
 #1: ffff888024da47d0 (&bdi->wb_switch_rwsem){+.+.}-{4:4}, at: sync_inodes_sb+0x19f/0xa10 fs/fs-writeback.c:2831
2 locks held by udevd/9605:
 #0: ffff888024acb5a8 (kn->active#5){.+.+}-{0:0}, at: inode_lock_shared include/linux/fs.h:884 [inline]
 #0: ffff888024acb5a8 (kn->active#5){.+.+}-{0:0}, at: blkdev_read_iter+0x2f8/0x440 block/fops.c:832
 #1: ffff8880b8639e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
2 locks held by syz-executor/9888:
 #0: ffffffff8fa02b38 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #0: ffffffff8fa02b38 (&ops->srcu#2){.+.+}-{0:0}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #0: ffffffff8fa02b38 (&ops->srcu#2){.+.+}-{0:0}, at: rtnl_link_ops_get+0x23/0x250 net/core/rtnetlink.c:570
 #1: ffffffff8f4fdc48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_lock net/core/rtnetlink.c:80 [inline]
 #1: ffffffff8f4fdc48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_nets_lock net/core/rtnetlink.c:341 [inline]
 #1: ffffffff8f4fdc48 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_newlink+0x8db/0x1c70 net/core/rtnetlink.c:4054
3 locks held by syz.5.471/10051:
 #0: ffff8880613a20e0 (&type->s_umount_key#51/1){+.+.}-{4:4}, at: alloc_super+0x204/0x970 fs/super.c:345
 #1: ffffffff8dfe5868 (wq_pool_mutex){+.+.}-{4:4}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
 #1: ffffffff8dfe5868 (wq_pool_mutex){+.+.}-{4:4}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
 #1: ffffffff8dfe5868 (wq_pool_mutex){+.+.}-{4:4}, at: is_bpf_text_address+0x26/0x2b0 kernel/bpf/core.c:772
 #2: ffff8880b8639e18 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2a/0x140 kernel/sched/core.c:606
2 locks held by udevd/10062:

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.16.0-rc3-syzkaller-00072-gee88bddf7f2f #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x17a/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+0xfee/0x1030 kernel/hung_task.c:470
 kthread+0x70e/0x8a0 kernel/kthread.c:464
 ret_from_fork+0x3fc/0x770 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 6547 Comm: syz-executor Not tainted 6.16.0-rc3-syzkaller-00072-gee88bddf7f2f #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:debug_smp_processor_id+0x0/0x20 lib/smp_processor_id.c:59
Code: c7 60 a9 1f 8e 4c 89 f6 e8 ed 2a 90 f9 e9 66 ff ff ff cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 c7 c7 60 b9 e1 8b 48 c7 c6 a0 b9 e1 8b eb 1c 66 66
RSP: 0000:ffffc90000007630 EFLAGS: 00000006
RAX: 0000000000000001 RBX: ffffffff902ffe01 RCX: ffff88802aae3c00
RDX: ffffc90000007701 RSI: dffffc0000000000 RDI: ffffc90000007730
RBP: dffffc0000000000 R08: ffffc90000007af8 R09: 0000000000000000
R10: ffffc90000007778 R11: fffff52000000ef1 R12: ffffc90000007b08
R13: ffffc90000000000 R14: ffffc90000007728 R15: ffffffff81728af5
FS:  000055557b6d0500(0000) GS:ffff888125c85000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f6544d5d260 CR3: 000000006bab8000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_is_watching_curr_cpu include/linux/context_tracking.h:128 [inline]
 rcu_is_watching+0x15/0xb0 kernel/rcu/tree.c:745
 rcu_read_unlock include/linux/rcupdate.h:869 [inline]
 class_rcu_destructor include/linux/rcupdate.h:1155 [inline]
 unwind_next_frame+0x1965/0x2390 arch/x86/kernel/unwind_orc.c:680
 arch_stack_walk+0x11c/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122
 kasan_save_stack+0x3e/0x60 mm/kasan/common.c:47
 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:548
 insert_work+0x3d/0x330 kernel/workqueue.c:2183
 __queue_work+0xbd9/0xfe0 kernel/workqueue.c:2345
 call_timer_fn+0x17b/0x5f0 kernel/time/timer.c:1747
 expire_timers kernel/time/timer.c:1793 [inline]
 __run_timers kernel/time/timer.c:2372 [inline]
 __run_timer_base+0x646/0x860 kernel/time/timer.c:2384
 run_timer_base kernel/time/timer.c:2393 [inline]
 run_timer_softirq+0xb7/0x180 kernel/time/timer.c:2403
 handle_softirqs+0x286/0x870 kernel/softirq.c:579
 __do_softirq kernel/softirq.c:613 [inline]
 invoke_softirq kernel/softirq.c:453 [inline]
 __irq_exit_rcu+0xca/0x1f0 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+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1050
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:console_trylock_spinning kernel/printk/printk.c:2061 [inline]
RIP: 0010:vprintk_emit+0x58f/0x7a0 kernel/printk/printk.c:2449
Code: 85 32 01 00 00 e8 e1 63 1f 00 41 89 df 4d 85 f6 48 8b 1c 24 75 07 e8 d0 63 1f 00 eb 06 e8 c9 63 1f 00 fb 48 c7 c7 e0 30 13 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 b9 36
RSP: 0000:ffffc90003dcf940 EFLAGS: 00000293
RAX: ffffffff81a0e9a7 RBX: ffffffff81a0e864 RCX: ffff88802aae3c00
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8e1330e0
RBP: ffffc90003dcfa50 R08: ffffffff8f9fe1f7 R09: 1ffffffff1f3fc3e
R10: dffffc0000000000 R11: fffffbfff1f3fc3f R12: dffffc0000000000
R13: 1ffff920007b9f2c R14: 0000000000000200 R15: 000000000000004c
 _printk+0xcf/0x120 kernel/printk/printk.c:2475
 __ext4_msg+0x293/0x2a0 fs/ext4/super.c:981
 ext4_put_super+0xb8/0xc40 fs/ext4/super.c:1286
 generic_shutdown_super+0x132/0x2c0 fs/super.c:643
 kill_block_super+0x44/0x90 fs/super.c:1755
 ext4_kill_sb+0x68/0xb0 fs/ext4/super.c:7391
 deactivate_locked_super+0xbc/0x130 fs/super.c:474
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1417
 task_work_run+0x1d1/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xec/0x110 kernel/entry/common.c:114
 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+0x2bd/0x3b0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f3a59d8fc57
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fff520d4bd8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f3a59e10925 RCX: 00007f3a59d8fc57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff520d4c90
RBP: 00007fff520d4c90 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff520d5d20
R13: 00007f3a59e10925 R14: 000000000005efa6 R15: 00007fff520d5d60
 </TASK>