INFO: task syz-executor:6531 blocked for more than 143 seconds.
      Not tainted 6.16.0-rc5-syzkaller-gec4801305969 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:6531  tgid:6531  ppid:1      task_flags:0x400140 flags:0x00000011
Call trace:
 __switch_to+0x414/0x834 arch/arm64/kernel/process.c:742 (T)
 context_switch kernel/sched/core.c:5401 [inline]
 __schedule+0x1414/0x2a28 kernel/sched/core.c:6790
 __schedule_loop kernel/sched/core.c:6868 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6883
 wb_wait_for_completion+0x150/0x280 fs/fs-writeback.c:216
 __writeback_inodes_sb_nr+0x1b0/0x218 fs/fs-writeback.c:2747
 writeback_inodes_sb_nr fs/fs-writeback.c:2764 [inline]
 writeback_inodes_sb+0x78/0x8c fs/fs-writeback.c:2779
 sync_filesystem+0xa0/0x218 fs/sync.c:54
 generic_shutdown_super+0x70/0x2b8 fs/super.c:622
 bch2_kill_sb+0x40/0x58 fs/bcachefs/fs.c:2618
 deactivate_locked_super+0xc4/0x12c fs/super.c:474
 deactivate_super+0xe0/0x100 fs/super.c:507
 cleanup_mnt+0x31c/0x3ac fs/namespace.c:1417
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1424
 task_work_run+0x1dc/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 do_notify_resume+0x174/0x1f4 arch/arm64/kernel/entry-common.c:155
 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:173 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:182 [inline]
 el0_svc+0xb8/0x180 arch/arm64/kernel/entry-common.c:880
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
1 lock held by khungtaskd/32:
 #0: ffff80008f8599c0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
2 locks held by kworker/u8:4/60:
 #0: ffff0000c2361148 ((wq_completion)writeback){+.+.}-{0:0}, at: process_one_work+0x63c/0x155c kernel/workqueue.c:3212
 #1: ffff800099b77bc0 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_one_work+0x6d4/0x155c kernel/workqueue.c:3212
1 lock held by udevd/6142:
2 locks held by getty/6287:
 #0: ffff0000d75380a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009ba2e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfa4 drivers/tty/n_tty.c:2222
2 locks held by syz-executor/6530:
1 lock held by syz-executor/6531:
 #0: ffff0000c83ea0e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock fs/super.c:57 [inline]
 #0: ffff0000c83ea0e0 (&type->s_umount_key#63){++++}-{4:4}, at: __super_lock_excl fs/super.c:72 [inline]
 #0: ffff0000c83ea0e0 (&type->s_umount_key#63){++++}-{4:4}, at: deactivate_super+0xd8/0x100 fs/super.c:506
2 locks held by kworker/0:2H/7267:
2 locks held by kworker/u8:12/7443:
2 locks held by syz.4.940/9851:
1 lock held by syz.3.951/9896:
1 lock held by syz.0.952/9894:

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