INFO: task syz-executor:4884 blocked for more than 143 seconds.
      Not tainted 5.15.173-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D
 stack:20504 pid: 4884 ppid:     1 flags:0x00004004
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373
 schedule+0x11b/0x1f0 kernel/sched/core.c:6456
 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191
 sync_inodes_sb+0x293/0xab0 fs/fs-writeback.c:2770
 sync_filesystem+0x16b/0x220 fs/sync.c:64
 generic_shutdown_super+0x6b/0x310 fs/super.c:448
 kill_block_super+0x7a/0xe0 fs/super.c:1427
 deactivate_locked_super+0xa0/0x110 fs/super.c:335
 cleanup_mnt+0x44e/0x500 fs/namespace.c:1143
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f4164dc5a47
RSP: 002b:00007ffdae302428 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f4164e371cc RCX: 00007f4164dc5a47
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffdae3024e0
RBP: 00007ffdae3024e0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffdae303560
R13: 00007f4164e371cc R14: 000000000001bceb R15: 00007ffdae3035a0
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/1:0/21:
1 lock held by khungtaskd/27:
 #0: ffffffff8cb1fc60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
4 locks held by kworker/u4:1/144:
 #0: ffff8881447b4938 ((wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: 
ffffc9000163fd20
 (
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: 
ffff88806727c650
 (sb_internal
#2
){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x20f/0x1180 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: ffff88806ee39768
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x23c/0x1180 fs/xfs/libxfs/xfs_bmap.c:4578
4 locks held by kworker/u4:2/154:
 #0: 
ffff8881447b4938
 (
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: ffffc90001f57d20 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff888077fce650
 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x20f/0x1180 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88806ee3dae8
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x23c/0x1180 fs/xfs/libxfs/xfs_bmap.c:4578
4 locks held by kworker/u4:3/361:
 #0: 
ffff8881447b4938
 (
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: 
ffffc90002fafd20
 (
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: 
ffff888072514650
 (
sb_internal
#2
){.+.+}-{0:0}
, at: xfs_bmapi_convert_delalloc+0x20f/0x1180 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88806eda00e8
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x23c/0x1180 fs/xfs/libxfs/xfs_bmap.c:4578
4 locks held by kworker/u4:4/1443:
 #0: 
ffff8881447b4938
 (
(wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: 
ffffc90005847d20
 ((work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff8880187dc650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x20f/0x1180 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88806ee3b568
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x23c/0x1180 fs/xfs/libxfs/xfs_bmap.c:4578
2 locks held by getty/3930:
 #0: 
ffff88802c670098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
 #1: ffffc90002cd62e8 (&ldata->atomic_read_lock
){+.+.}-{3:3}
, at: n_tty_read+0x6af/0x1db0 drivers/tty/n_tty.c:2158
5 locks held by kworker/0:10/4759:
2 locks held by syz-executor/4884:
 #0: 
ffff8880725140e0
 (
&type->s_umount_key
#52
){+.+.}-{3:3}
, at: deactivate_super+0xa9/0xe0 fs/super.c:365
 #1: 
ffff88802078a7d8
 (
&bdi->wb_switch_rwsem
){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2768
2 locks held by syz-executor/5129:
 #0: ffff88806727c0e0 (&type->s_umount_key#52){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
 #1: ffff8881478987d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff8881478987d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2768
2 locks held by syz-executor/5153:
 #0: ffff8880187dc0e0 (&type->s_umount_key#52){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
 #1: ffff88814789e7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff88814789e7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2768
2 locks held by syz-executor/5178:
 #0: ffff888077fce0e0 (&type->s_umount_key#52){+.+.}-{3:3}, at: deactivate_super+0xa9/0xe0 fs/super.c:365
 #1: ffff8880208ac7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff8880208ac7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2768
2 locks held by syz-executor/5217:
 #0: ffff888076c2a0e0 (&type->s_umount_key
#52
){+.+.}-{3:3}
, at: deactivate_super+0xa9/0xe0 fs/super.c:365
 #1: 
ffff8880208ba7d8
 (
&bdi->wb_switch_rwsem){+.+.}-{3:3}
, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
, at: sync_inodes_sb+0x274/0xab0 fs/fs-writeback.c:2768
4 locks held by kworker/u4:9/5280:
 #0: ffff8881447b4938 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x78a/0x10c0 kernel/workqueue.c:2283
 #1: 
ffffc9000371fd20 (
(work_completion)(&(&wb->dwork)->work)
){+.+.}-{0:0}
, at: process_one_work+0x7d0/0x10c0 kernel/workqueue.c:2285
 #2: ffff888076c2a650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x20f/0x1180 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff88805cb79ee8
 (
&xfs_nondir_ilock_class
){++++}-{3:3}
, at: xfs_bmapi_convert_delalloc+0x23c/0x1180 fs/xfs/libxfs/xfs_bmap.c:4578
2 locks held by syz-executor/5293:
 #0: 
ffffffff8dc41388 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
ffffffff8dc41388 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5644
 #1: 
ffffffff8cb24228
 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:845

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

NMI backtrace for cpu 1
CPU: 1 PID: 27 Comm: khungtaskd Not tainted 5.15.173-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
 watchdog+0xe72/0xeb0 kernel/hung_task.c:295
 kthread+0x3f6/0x4f0 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: 4759 Comm: kworker/0:10 Not tainted 5.15.173-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: xfs-buf/loop2 xfs_buf_ioend_work
RIP: 0010:preempt_count_add+0x40/0x180 kernel/sched/core.c:5490
Code: 00 00 00 fc ff df 42 0f b6 04 38 84 c0 0f 85 e2 00 00 00 83 3d 70 74 51 15 00 75 07 65 8b 05 6f f4 aa 7e 65 01 1d 68 f4 aa 7e <48> c7 c0 c0 ef a8 96 48 c1 e8 03 42 0f b6 04 38 84 c0 0f 85 d9 00
RSP: 0018:ffffc90002fdf350 EFLAGS: 00000086
RAX: 0000000080000002 RBX: 0000000000000001 RCX: ffffffff96a8ef03
RDX: 000000000000008d RSI: ffffffff8af9ece0 RDI: 0000000000000001
RBP: 00000000000004ba R08: ffffffff84857dc9 R09: 0000000000000003
R10: ffffffffffffffff R11: dffffc0000000001 R12: 1ffffffff2db6b8d
R13: ffffffff96db59c0 R14: 0000000000000899 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc8d1e94440 CR3: 000000001f419000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 delay_tsc+0x62/0xd0 arch/x86/lib/delay.c:79
 wait_for_xmitr+0xb8/0x260 drivers/tty/serial/8250/8250_port.c:2077
 serial8250_console_putchar+0x19/0x50 drivers/tty/serial/8250/8250_port.c:3301
 uart_console_write+0xa9/0x100 drivers/tty/serial/serial_core.c:1981
 serial8250_console_write+0xc8e/0x1180 drivers/tty/serial/8250/8250_port.c:3378
 console_unlock+0xced/0x12b0 kernel/printk/printk.c:2744
 vprintk_emit+0xbf/0x150 kernel/printk/printk.c:2274
 _printk+0xd1/0x120 kernel/printk/printk.c:2299
 print_hex_dump+0x1a2/0x250 lib/hexdump.c:285
 xfs_hex_dump+0x39/0x50 fs/xfs/xfs_message.c:118
 xfs_buf_verifier_error+0x1bc/0x290 fs/xfs/xfs_error.c:418
 xfs_allocbt_read_verify+0x52/0xc0
 xfs_buf_ioend+0x26a/0x6e0 fs/xfs/xfs_buf.c:1263
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>