[v5.15] INFO: task hung in devtmpfs_delete_node

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b925f60c6ee7 Linux 5.15.157
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1552e537180000
kernel config: https://syzkaller.appspot.com/x/.config?x=802c8e49b2826f05
dashboard link: https://syzkaller.appspot.com/bug?extid=47393ebbcb8c19464747
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/add896a77889/disk-b925f60c.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e24f83a46999/vmlinux-b925f60c.xz
kernel image: https://storage.googleapis.com/syzbot-assets/de040a426c29/Image-b925f60c.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+47393e...@syzkaller.appspotmail.com

INFO: task syz-executor.4:5947 blocked for more than 143 seconds.
Not tainted 5.15.157-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack: 0 pid: 5947 ppid: 4913 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
schedule_timeout+0xb8/0x344 kernel/time/timer.c:1890
do_wait_for_common+0x214/0x388 kernel/sched/completion.c:85
__wait_for_common kernel/sched/completion.c:106 [inline]
wait_for_common kernel/sched/completion.c:117 [inline]
wait_for_completion+0x4c/0x64 kernel/sched/completion.c:138
devtmpfs_submit_req drivers/base/devtmpfs.c:110 [inline]
devtmpfs_delete_node+0x1c8/0x2a0 drivers/base/devtmpfs.c:159
device_del+0x2d4/0x9b4 drivers/base/core.c:3578
cdev_device_del+0x30/0x10c fs/char_dev.c:573
evdev_disconnect+0x50/0xc0 drivers/input/evdev.c:1406
__input_unregister_device+0x19c/0x304 drivers/input/input.c:2208
input_unregister_device+0xb0/0xfc drivers/input/input.c:2398
uinput_destroy_device+0x5a4/0x79c drivers/input/misc/uinput.c:298
uinput_release+0x44/0x60 drivers/input/misc/uinput.c:710
__fput+0x30c/0x7f0 fs/file_table.c:280
____fput+0x20/0x30 fs/file_table.c:308
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:
1 lock held by init/1:
#0: ffff8000150871b8 (tomoyo_ss){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311
3 locks held by kdevtmpfs/23:
1 lock held by khungtaskd/27:
#0: ffff800014b114e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:311
1 lock held by kswapd0/213:
1 lock held by syslogd/3568:
#0: ffff8000150871b8 (tomoyo_ss){....}-{0:0}, at: rcu_lock_acquire+0x10/0x4c include/linux/rcupdate.h:311
1 lock held by dhcpcd/3634:
2 locks held by getty/3726:
#0: ffff0000d32c2098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x40/0x50 drivers/tty/tty_ldsem.c:340
#1: ffff80001a25e2e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1204 drivers/tty/n_tty.c:2158
2 locks held by syz-fuzzer/3957:
2 locks held by syz-fuzzer/3962:
1 lock held by syz-fuzzer/4000:
2 locks held by syz-executor.4/4913:
#0: ffff0000dc0c8ff0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_dev_do_close+0x64/0x1060 net/bluetooth/hci_core.c:1737
#1: ffff0000dc0c8078 (&hdev->lock){+.+.}-{3:3}, at: hci_dev_do_close+0x338/0x1060 net/bluetooth/hci_core.c:1782
1 lock held by syz-executor.4/5947:
#0: ffff8000161ff148 (input_mutex){+.+.}-{3:3}, at: __input_unregister_device+0x10c/0x304 drivers/input/input.c:2205

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