INFO: task syz-executor.3:7537 blocked for more than 155 seconds.
      Not tainted 5.15.147-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3  state:D stack:    0 pid: 7537 ppid:  4020 flags:0x0000000d
Call trace:
 __switch_to+0x308/0x5e8 arch/arm64/kernel/process.c:518
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0xf10/0x1e48 kernel/sched/core.c:6376
 schedule+0x11c/0x1c8 kernel/sched/core.c:6459
 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+0x70/0x29c fs/super.c:448
 kill_block_super+0x70/0xdc fs/super.c:1414
 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:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x670/0x20bc kernel/exit.c:872
 do_group_exit+0x110/0x268 kernel/exit.c:994
 get_signal+0x634/0x1550 kernel/signal.c:2889
 do_signal arch/arm64/kernel/signal.c:890 [inline]
 do_notify_resume+0x3d0/0x32b8 arch/arm64/kernel/signal.c:943
 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:
2 locks held by kworker/1:0/21:
1 lock held by khungtaskd/27:
 #0: ffff800014af15e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:268
1 lock held by klogd/3581:
1 lock held by udevd/3592:
 #0: ffff0000cb370118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x12c/0x89c block/bdev.c:817
2 locks held by getty/3734:
 #0: ffff0000d3e30098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
 #1: ffff80001c26e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
2 locks held by syz-fuzzer/3971:
4 locks held by kworker/u4:14/5116:
4 locks held by kworker/u4:15/5158:
 #0: ffff0000c0b70138 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x66c/0x11b8 kernel/workqueue.c:2283
 #1: ffff800026397c00 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6ac/0x11b8 kernel/workqueue.c:2285
 #2: ffff0000d45e8650 (sb_internal#2){.+.+}-{0:0}, at: xfs_bmapi_convert_delalloc+0x1e0/0x1018 fs/xfs/libxfs/xfs_bmap.c:4573
 #3: ffff0000c0561ee8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: mrupdate_nested fs/xfs/mrlock.h:36 [inline]
 #3: ffff0000c0561ee8 (&xfs_nondir_ilock_class){++++}-{3:3}, at: xfs_ilock+0x26c/0x4c4 fs/xfs/xfs_inode.c:200
2 locks held by kworker/u4:20/6158:
2 locks held by syz-executor.3/7537:
 #0: ffff0000d45e80e0 (&type->s_umount_key#65){++++}-{3:3}, at: deactivate_super+0x100/0x128 fs/super.c:365
 #1: ffff0000cb30c7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline]
 #1: ffff0000cb30c7d8 (&bdi->wb_switch_rwsem){+.+.}-{3:3}, at: sync_inodes_sb+0x208/0x944 fs/fs-writeback.c:2768
1 lock held by syz-executor.5/7863:
 #0: ffff0000cb370118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_get_by_dev+0x12c/0x89c block/bdev.c:817
1 lock held by syz-executor.3/9567:
 #0: ffff0000d45e80e0 (&type->s_umount_key#65){++++}-{3:3}, at: user_get_super+0xd8/0x240 fs/super.c:835
2 locks held by syz-executor.2/11094:
 #0: ffff0000cb2f2918 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe0/0x6b0 block/bdev.c:912
 #1: ffff0000cb1ff468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x58/0x210 drivers/block/loop.c:2070
2 locks held by syz-executor.1/11095:
 #0: ffff0000cb20e118 (&disk->open_mutex){+.+.}-{3:3}, at: blkdev_put+0xe0/0x6b0 block/bdev.c:912
 #1: ffff0000cb1fc468 (&lo->lo_mutex){+.+.}-{3:3}, at: lo_release+0x58/0x210 drivers/block/loop.c:2070
2 locks held by syz-executor.4/11101:
1 lock held by syz-executor.3/11103:

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