syzbot

INFO: task syz.3.403:9459 blocked for more than 144 seconds.
      Not tainted 6.11.0-rc5-syzkaller-gdf54f4a16f82 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.3.403       state:D stack:0     pid:9459  tgid:9458  ppid:6401   flags:0x0000000d
Call trace:
 __switch_to+0x418/0x658 arch/arm64/kernel/process.c:579
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0x13d4/0x2418 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0xbc/0x238 kernel/sched/core.c:6621
 schedule_timeout+0xb8/0x33c kernel/time/timer.c:2557
 do_wait_for_common+0x30c/0x468 kernel/sched/completion.c:95
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x48/0x60 kernel/sched/completion.c:148
 kthread_flush_worker+0x214/0x2d4 kernel/kthread.c:1393
 alloc_workqueue+0x1314/0x1a90 kernel/workqueue.c:5728
 btrfs_init_workqueues+0x1e4/0x5cc fs/btrfs/disk-io.c:1993
 open_ctree+0xe2c/0x21b0 fs/btrfs/disk-io.c:3364
 btrfs_fill_super fs/btrfs/super.c:965 [inline]
 btrfs_get_tree_super fs/btrfs/super.c:1888 [inline]
 btrfs_get_tree+0xdd0/0x1368 fs/btrfs/super.c:2114
 vfs_get_tree+0x90/0x28c fs/super.c:1800
 fc_mount+0x24/0xac fs/namespace.c:1231
 btrfs_get_tree_subvol fs/btrfs/super.c:2077 [inline]
 btrfs_get_tree+0x4e4/0x1368 fs/btrfs/super.c:2115
 vfs_get_tree+0x90/0x28c fs/super.c:1800
 do_new_mount+0x278/0x900 fs/namespace.c:3472
 path_mount+0x590/0xe04 fs/namespace.c:3799
 do_mount fs/namespace.c:3812 [inline]
 __do_sys_mount fs/namespace.c:4020 [inline]
 __se_sys_mount fs/namespace.c:3997 [inline]
 __arm64_sys_mount+0x45c/0x5a8 fs/namespace.c:3997
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132
 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151
 el0_svc+0x54/0x168 arch/arm64/kernel/entry-common.c:712
 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:730
 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:598

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffff80008f6edba0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:325
2 locks held by kworker/u8:8/683:
2 locks held by getty/6153:
 #0: ffff0000d21da0a0 (&tty->ldisc_sem
){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009836e2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x41c/0x1228 drivers/tty/n_tty.c:2211
4 locks held by syz-executor/6395:
3 locks held by syz-executor/6403:
2 locks held by udevd/8179:
1 lock held by udevd/8181:
1 lock held by syz.3.403/9459:
 #0: ffff0000dbc8a0e0 (&type->s_umount_key#59/1){+.+.}-{3:3}, at: alloc_super+0x1b0/0x83c fs/super.c:344
1 lock held by syz.4.480/10164:
 #0: ffff0000c8c680e0 (&type->s_umount_key#59/1){+.+.}-{3:3}, at: alloc_super+0x1b0/0x83c fs/super.c:344
1 lock held by udevadm/11854:
2 locks held by syz.2.678/11877:

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