INFO: task syz.0.831:8469 blocked for more than 143 seconds.
      Tainted: G             L      syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.831       state:D stack:0     pid:8469  tgid:8467  ppid:7881   task_flags:0x400140 flags:0x00000001
Call trace:
 __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:775 (T)
 context_switch kernel/sched/core.c:5510 [inline]
 __schedule+0x1370/0x2d80 kernel/sched/core.c:7234
 __schedule_loop kernel/sched/core.c:7311 [inline]
 schedule+0x13c/0x20c kernel/sched/core.c:7326
 cgroup_lock_and_drain_offline+0x490/0x604 kernel/cgroup/cgroup.c:3275
 cgroup1_get_tree+0xa0/0x7d8 kernel/cgroup/cgroup-v1.c:1265
 vfs_get_tree+0x90/0x28c fs/super.c:1694
 fc_mount+0x24/0xac fs/namespace.c:1198
 do_new_mount_fc fs/namespace.c:3765 [inline]
 do_new_mount+0x2a4/0x538 fs/namespace.c:3841
 path_mount+0x5f0/0xa88 fs/namespace.c:4161
 do_mount+0xe8/0x148 fs/namespace.c:4174
 __do_sys_mount fs/namespace.c:4390 [inline]
 __se_sys_mount fs/namespace.c:4367 [inline]
 __arm64_sys_mount+0x334/0x380 fs/namespace.c:4367
 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
 invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
 el0_svc_common+0xec/0x23c arch/arm64/kernel/syscall.c:121
 do_el0_svc+0x4c/0x5c arch/arm64/kernel/syscall.c:140
 el0_svc+0x64/0x260 arch/arm64/kernel/entry-common.c:736
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

Showing all locks held in the system:
2 locks held by kworker/0:1/10:
3 locks held by kworker/u8:0/12:
3 locks held by kworker/u8:1/15:
1 lock held by khungtaskd/31:
 #0: ffff800088cf6fe0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff800088cf6fe0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:840 [inline]
 #0: ffff800088cf6fe0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6775
4 locks held by kworker/R-write/33:
3 locks held by kworker/u8:2/39:
3 locks held by kworker/u8:3/40:
3 locks held by kworker/u8:4/138:
2 locks held by kworker/0:2/867:
3 locks held by kworker/u8:5/1100:
2 locks held by kworker/R-bat_e/2850:
3 locks held by kworker/u8:6/3588:
1 lock held by klogd/4330:
1 lock held by udevd/4341:
1 lock held by dhcpcd/4397:
2 locks held by getty/4490:
 #0: ffff0000cd14b0a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff8000924cb2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x348/0xf78 drivers/tty/n_tty.c:2211
1 lock held by udevd/4701:
2 locks held by kworker/0:3/4796:
2 locks held by kworker/0:5/4804:
2 locks held by kworker/0:6/4818:
2 locks held by kworker/u8:7/4861:
3 locks held by kworker/u8:8/5035:
3 locks held by kworker/u8:9/5217:
3 locks held by kworker/u8:11/5219:
3 locks held by kworker/u8:12/5222:
2 locks held by syz-executor/6557:
3 locks held by syz.6.1184/10292:
 #0: ffff0000cff6a470 (&f->f_pos_lock){+.+.}-{4:4}, at: fdget_pos+0x100/0x144 fs/file.c:1259
 #1: ffff0000d3b32450 (sb_writers#7){.+.+}-{0:0}, at: file_start_write include/linux/fs.h:2733 [inline]
 #1: ffff0000d3b32450 (sb_writers#7){.+.+}-{0:0}, at: vfs_write+0x248/0xa0c fs/read_write.c:683
 #2: ffff0000d6575080 (&of->mutex){+.+.}-{4:4}, at: kernfs_fop_write_iter+0x1b0/0x3b8 fs/kernfs/file.c:336
1 lock held by syz.0.1483/12068:
1 lock held by syz.2.1484/12086:
1 lock held by syz.9.1485/12087:

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