INFO: task syz-executor:4813 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:21968 pid: 4813 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5049 [inline]
 __schedule+0x11ef/0x43c0 kernel/sched/core.c:6395
 schedule+0x11b/0x1e0 kernel/sched/core.c:6478
 wb_wait_for_completion+0x171/0x290 fs/fs-writeback.c:191
 sync_inodes_sb+0x1bd/0x950 fs/fs-writeback.c:2787
 sync_filesystem+0x16d/0x220 fs/sync.c:64
 generic_shutdown_super+0x6b/0x300 fs/super.c:448
 kill_block_super+0x7c/0xe0 fs/super.c:1427
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f351e0fcb57
RSP: 002b:00007ffc1a5d7d48 EFLAGS: 00000246
 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f351e18c64a RCX: 00007f351e0fcb57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc1a5d7e00
RBP: 00007ffc1a5d7e00 R08: 00007ffc1a5d8e00 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffc1a5d8e90
R13: 00007f351e18c64a R14: 000000000001a8af R15: 00007ffc1a5d8ed0
 </TASK>

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
 #0: 
ffff88801a590138
 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90000ce7d00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: 
ffff888077922650
 (
sb_internal
#2
){.+.+}-{0:0}
, at: xfs_bmapi_convert_delalloc+0x224/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88805bda1768
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x25b/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4578
1 lock held by khungtaskd/27:
 #0: 
ffffffff8c31eaa0
 (
rcu_read_lock
){....}-{1:2}
, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:1/144:
 #0: 
ffff88801a590138
 (
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: 
ffffc9000174fd00
 (
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff88801edfc650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x224/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: ffff88805bec8fe8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_bmapi_convert_delalloc+0x25b/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4578
3 locks held by kworker/u4:2/145:
 #0: ffff888016c79138 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc9000175fd00 ((linkwatch_work).work
){+.+.}-{0:0}
, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffffff8d43c748 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:251
4 locks held by kworker/u4:3/156:
 #0: 
ffff88801a590138
 (
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: 
ffffc90002087d00
 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffff8880185a8650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x224/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88805bd11768
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x25b/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4578
4 locks held by kworker/u4:4/1214:
 #0: 
ffff88801a590138
 (
(wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: ffffc90004d0fd00 ((work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: 
ffff888020c8c650
 (
sb_internal
#2
){.+.+}-{0:0}
, at: xfs_bmapi_convert_delalloc+0x224/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88805bda69e8
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x25b/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4578
4 locks held by kworker/u4:5/1234:
 #0: 
ffff88801a590138
 (
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: 
ffffc90004f2fd00
 (
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: 
ffff888029862650
 (
sb_internal
#2
){.+.+}-{0:0}
, at: xfs_bmapi_convert_delalloc+0x224/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88805bda4be8
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x25b/0xdb0 fs/xfs/libxfs/xfs_bmap.c:4578
2 locks held by getty/3948:
 #0: 
ffff88814ca2d098
 (
&tty->ldisc_sem
){++++}-{0:0}
, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: 
ffffc900025e62e8
 (
&ldata->atomic_read_lock
){+.+.}-{3:3}
, at: n_tty_read+0x5df/0x1a70 drivers/tty/n_tty.c:2158
5 locks held by kworker/1:16/4262:
2 locks held by kworker/0:13/4674:
 #0: 
ffff888016c72138
 (
(wq_completion)rcu_gp
){+.+.}-{0:0}
, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: 
ffffc9000321fd00
 (
(work_completion)(&rew.rew_work)
){+.+.}-{0:0}
, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
3 locks held by kworker/0:17/4678:
 #0: 
ffff8880b903a358
 (
&rq->__lock
){-.-.}-{2:2}
, at: process_one_work+0x761/0x1010 kernel/workqueue.c:-1
 #1: 
ffffc9000325fd00
 (
(work_completion)(&bp->b_ioend_work)){+.+.}-{0:0}, at: process_one_work+0x79f/0x1010 kernel/workqueue.c:2285
 #2: ffffc90000007be0 (&(&slave->notify_work)->timer){..-.}-{0:0}, at: lockdep_copy_map include/linux/lockdep.h:45 [inline]
 #2: ffffc90000007be0 (&(&slave->notify_work)->timer){..-.}-{0:0}, at: call_timer_fn+0xca/0x540 kernel/time/timer.c:1638
2 locks held by syz-executor/4813:
 #0: 
ffff8880779220e0
 (
&type->s_umount_key
#54
){+.+.}-{3:3}
, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: 
ffff8881474c47d8
 (
&bdi->wb_switch_rwsem){+.+.}-{3:3}
, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
, at: sync_inodes_sb+0x1a1/0x950 fs/fs-writeback.c:2785
2 locks held by syz-executor/5072:
 #0: ffff8880185a80e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffff8881474da7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}
, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
, at: sync_inodes_sb+0x1a1/0x950 fs/fs-writeback.c:2785
2 locks held by syz-executor/5103:
 #0: 
ffff8880298620e0
 (
&type->s_umount_key
#54
){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: ffff8881474e87d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff8881474e87d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x1a1/0x950 fs/fs-writeback.c:2785
2 locks held by syz-executor/5168:
 #0: ffff888020c8c0e0 (&type->s_umount_key#54){+.+.}-{3:3}, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: 
ffff8881474ee7d8
 (
&bdi->wb_switch_rwsem
){+.+.}-{3:3}
, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
, at: sync_inodes_sb+0x1a1/0x950 fs/fs-writeback.c:2785
2 locks held by syz-executor/5202:
 #0: 
ffff88801edfc0e0
 (
&type->s_umount_key
#54
){+.+.}-{3:3}
, at: deactivate_super+0xa0/0xd0 fs/super.c:365
 #1: 
ffff8881474f47d8
 (
&bdi->wb_switch_rwsem
){+.+.}-{3:3}
, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
, at: sync_inodes_sb+0x1a1/0x950 fs/fs-writeback.c:2785
2 locks held by syz-executor/5259:
 #0: 
ffffffff8d43c748
 (
rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7ee/0xf30 net/core/rtnetlink.c:5681
 #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 #1: ffffffff8c323528 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x2d1/0x750 kernel/rcu/tree_exp.h:845

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline]
 watchdog+0xe0f/0xe50 kernel/hung_task.c:369
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4673 Comm: kworker/0:12 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026
Workqueue: xfs-buf/loop4 xfs_buf_ioend_work
RIP: 0010:look_up_lock_class+0x6c/0x110 kernel/locking/lockdep.c:889
Code: 24 00 02 00 00 0f 85 93 00 00 00 89 f0 49 01 c7 48 b8 eb 83 b5 80 46 86 c8 61 49 0f af c7 48 c1 e8 34 48 8b 1c c5 00 67 a6 92 <e8> 4f 01 00 00 48 85 db 74 4b 4c 39 7b 40 74 05 48 8b 1b eb eb 48
RSP: 0018:ffffc900000076f0 EFLAGS: 00000006
RAX: 000000000000063a RBX: ffffffff8fbc3a00 RCX: ffffffff962d8f03
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffc90000007be0
RBP: ffffc900000077f0 R08: dffffc0000000000 R09: 0000000000000000
R10: dffffc0000000000 R11: fffffbfff1b13b66 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffc90000007be0 R15: ffffffff9664ccc0
FS:  0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f31b911de00 CR3: 000000002b14e000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 register_lock_class+0xc0/0x890 kernel/locking/lockdep.c:1245
 __lock_acquire+0x16f/0x7d10 kernel/locking/lockdep.c:4891
 lock_acquire+0x19e/0x400 kernel/locking/lockdep.c:5623
 call_timer_fn+0xe6/0x540 kernel/time/timer.c:1645
 expire_timers kernel/time/timer.c:1699 [inline]
 __run_timers+0x53e/0x800 kernel/time/timer.c:1970
 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
 handle_softirqs+0x339/0x830 kernel/softirq.c:576
 __do_softirq kernel/softirq.c:610 [inline]
 invoke_softirq kernel/softirq.c:450 [inline]
 __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659
 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:console_trylock_spinning+0x301/0x370 kernel/printk/printk.c:1909
Code: 85 db 74 89 e8 50 e7 18 00 fb 31 c0 eb 48 e8 46 e7 18 00 e8 d1 dd 5b 08 48 85 db 74 d1 e8 37 e7 18 00 fb 48 c7 c7 e0 35 31 8c <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 68 0a 3b 60
RSP: 0018:ffffc900031ff720 EFLAGS: 00000293
RAX: ffffffff81603b09 RBX: 0000000000000200 RCX: ffff88807d6b3b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c3135e0
RBP: ffffc900031ff7f0 R08: ffffffff901d2207 R09: 1ffffffff203a440
R10: dffffc0000000000 R11: fffffbfff203a441 R12: dffffc0000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 1ffff9200063fee4
 vprintk_emit+0xa7/0x150 kernel/printk/printk.c:2273
 _printk+0xda/0x130 kernel/printk/printk.c:2299
 print_hex_dump+0x1cf/0x2b0 lib/hexdump.c:285
 xfs_hex_dump+0x39/0x50 fs/xfs/xfs_message.c:118
 xfs_buf_verifier_error+0x1ba/0x290 fs/xfs/xfs_error.c:418
 xfs_agf_read_verify+0x1d2/0x250 fs/xfs/libxfs/xfs_alloc.c:-1
 xfs_buf_ioend+0x25c/0x6e0 fs/xfs/xfs_buf.c:1263
 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
 kthread+0x436/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>