INFO: task syz-executor.5:4324 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.5  state:D
 stack:    0 pid: 4324 ppid:  4297 flags:0x00000004
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5027 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6373
 schedule+0x11c/0x1c8 kernel/sched/core.c:6456
 wb_wait_for_completion+0x160/0x2b4 fs/fs-writeback.c:191
 sync_inodes_sb+0x220/0x944 fs/fs-writeback.c:2770
 sync_filesystem+0x160/0x218 fs/sync.c:64
 generic_shutdown_super+0x70/0x2f0 fs/super.c:448
 kill_block_super+0x70/0xdc fs/super.c:1427
 deactivate_locked_super+0xb8/0x13c fs/super.c:335
 deactivate_super+0x108/0x128 fs/super.c:366
 cleanup_mnt+0x3c0/0x474 fs/namespace.c:1143
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1150
 task_work_run+0x130/0x1e4 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline]
 el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609
 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626
 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584

Showing all locks held in the system:
4 locks held by kworker/u4:0/9:
 #0: 
ffff0000c21d8138
 ((wq_completion)writeback
){+.+.}-{0:0}
, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001bce7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000d5b0c650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1e0/0x1018 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: ffff0000e15f2668 (&xfs_nondir_ilock_class){++++}-{3:3}, at: mrupdate_nested fs/xfs/mrlock.h:36 [inline]
 #3: ffff0000e15f2668 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0x26c/0x4c4 fs/xfs/xfs_inode.c:200
1 lock held by khungtaskd/27:
 #0: ffff800014d322e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
4 locks held by kworker/u4:4/360:
 #0: ffff0000c21d8138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800020057c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000d8d30650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1e0/0x1018 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: ffff0000e15f69e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: mrupdate_nested fs/xfs/mrlock.h:36 [inline]
 #3: ffff0000e15f69e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0x26c/0x4c4 fs/xfs/xfs_inode.c:200
5 locks held by kworker/0:2/1960:
2 locks held by getty/3788:
 #0: ffff0000d3a56098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001d6ae2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
2 locks held by syz-executor.5/4324:
 #0: ffff0000d5b0c0e0
 (&type->s_umount_key#49){+.+.}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
 #1: ffff0000cb9d67d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff0000cb9d67d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x208/0x944 fs/fs-writeback.c:2768
4 locks held by kworker/u4:7/4511:
 #0: ffff0000c21d8138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001fc17c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000ce67c650
 (
sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1e0/0x1018 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: ffff0000e15b78e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: mrupdate_nested fs/xfs/mrlock.h:36 [inline]
 #3: ffff0000e15b78e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0x26c/0x4c4 fs/xfs/xfs_inode.c:200
4 locks held by kworker/u4:8/4532:
 #0: ffff0000c21d8138
 ((wq_completion)writeback
){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff80001fca7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000c11d6650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1e0/0x1018 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: 
ffff0000e7258868 (&xfs_nondir_ilock_class){++++}-{3:3}, at: mrupdate_nested fs/xfs/mrlock.h:36 [inline]
ffff0000e7258868 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0x26c/0x4c4 fs/xfs/xfs_inode.c:200
4 locks held by kworker/u4:9/4832:
 #0: ffff0000c21d8138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff8000202b7c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000ce1b0650 (sb_internal
#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1e0/0x1018 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: ffff0000e15f00e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: mrupdate_nested fs/xfs/mrlock.h:36 [inline]
 #3: ffff0000e15f00e8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0x26c/0x4c4 fs/xfs/xfs_inode.c:200
2 locks held by syz-executor.1/5835:
 #0: ffff0000d8d300e0 (&type->s_umount_key#49){+.+.}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
 #1: ffff0000cb8fe7d8
 (&bdi->wb_switch_rwsem
){+.+.}-{3:3}
, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
, at: sync_inodes_sb+0x208/0x944 fs/fs-writeback.c:2768
2 locks held by syz-executor.2/5840:
 #0: ffff0000ce1b00e0 (&type->s_umount_key#49){+.+.}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
 #1: ffff0000cb94c7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff0000cb94c7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x208/0x944 fs/fs-writeback.c:2768
2 locks held by syz-executor.0/5843:
 #0: ffff0000ce67c0e0 (&type->s_umount_key#49){+.+.}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
 #1: ffff0000cb8f87d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff0000cb8f87d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x208/0x944 fs/fs-writeback.c:2768
2 locks held by syz-executor.4/5846:
 #0: ffff0000c11d60e0 (&type->s_umount_key#49){+.+.}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
 #1: ffff0000cb9d07d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff0000cb9d07d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x208/0x944 fs/fs-writeback.c:2768

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