[v6.1] INFO: task hung in bfs_lookup

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3a8358583626 Linux 6.1.129
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=1270ca97980000
kernel config: https://syzkaller.appspot.com/x/.config?x=ff93ecc085d8436e
dashboard link: https://syzkaller.appspot.com/bug?extid=329c4002dad0055b432b
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=104185a8580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=102717b8580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/3cc3985223b7/disk-3a835858.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/e40398fb298b/vmlinux-3a835858.xz
kernel image: https://storage.googleapis.com/syzbot-assets/40469708dc9a/Image-3a835858.gz.xz
mounted in repro: https://storage.googleapis.com/syzbot-assets/a7060254dd04/mount_0.gz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+329c40...@syzkaller.appspotmail.com

INFO: task syz-executor185:4296 blocked for more than 143 seconds.
Not tainted 6.1.129-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor185 state:D stack:0 pid:4296 ppid:4292 flags:0x0000000d
Call trace:
__switch_to+0x308/0x598 arch/arm64/kernel/process.c:553
context_switch kernel/sched/core.c:5243 [inline]
__schedule+0xef4/0x1d44 kernel/sched/core.c:6560
schedule+0xc4/0x170 kernel/sched/core.c:6636
schedule_preempt_disabled+0x18/0x2c kernel/sched/core.c:6695
__mutex_lock_common+0xbd8/0x21a0 kernel/locking/mutex.c:679
__mutex_lock kernel/locking/mutex.c:747 [inline]
mutex_lock_nested+0x38/0x44 kernel/locking/mutex.c:799
bfs_lookup+0x11c/0x228 fs/bfs/dir.c:136
__lookup_slow+0x250/0x374 fs/namei.c:1690
lookup_slow+0x60/0x84 fs/namei.c:1707
walk_component fs/namei.c:1998 [inline]
link_path_walk+0x830/0xcc8 fs/namei.c:2325
path_parentat fs/namei.c:2526 [inline]
__filename_parentat+0x1e4/0x5d0 fs/namei.c:2550
filename_parentat fs/namei.c:2568 [inline]
filename_create+0xf0/0x468 fs/namei.c:3857
do_mkdirat+0xac/0x510 fs/namei.c:4121
__do_sys_mkdirat fs/namei.c:4146 [inline]
__se_sys_mkdirat fs/namei.c:4144 [inline]
__arm64_sys_mkdirat+0x90/0xa8 fs/namei.c:4144
__invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637
el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffff800015cc79b0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
#0: ffff800015cc81b0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x44/0xcf4 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
#0: ffff800015cc77e0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349
2 locks held by getty/4054:
#0: ffff0000d5f76098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
#1: ffff80001d8f02f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x414/0x1214 drivers/tty/n_tty.c:2198
3 locks held by syz-executor185/4294:
2 locks held by syz-executor185/4296:
#0: ffff0000e1b4c168 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: inode_lock_shared include/linux/fs.h:768 [inline]
#0: ffff0000e1b4c168 (&type->i_mutex_dir_key#8){.+.+}-{3:3}, at: lookup_slow+0x50/0x84 fs/namei.c:1706
#1: ffff0000c316d8d8 (&info->bfs_lock){+.+.}-{3:3}, at: bfs_lookup+0x11c/0x228 fs/bfs/dir.c:136

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