[syzbot] [kernfs?] INFO: task hung in kernfs_dop_revalidate (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4a4be1ad3a6e Revert "vfs: Delete the associated dentry whe..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=17012bd2980000
kernel config: https://syzkaller.appspot.com/x/.config?x=b9016f104992d69c
dashboard link: https://syzkaller.appspot.com/bug?extid=da20d108162166514db6
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=150e4b0c980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16c039c2980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/e323e970d41d/disk-4a4be1ad.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/f0dfe36102b9/vmlinux-4a4be1ad.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9ca35ad0fa6a/bzImage-4a4be1ad.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+da20d1...@syzkaller.appspotmail.com

INFO: task udevd:4544 blocked for more than 143 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:udevd state:D
stack:24048 pid:4544 tgid:4544 ppid:1 flags:0x00000002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_read_slowpath kernel/locking/rwsem.c:1086 [inline]
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x705/0xa40 kernel/locking/rwsem.c:1528
kernfs_dop_revalidate+0xd4/0x560 fs/kernfs/dir.c:1159
lookup_fast+0x1f4/0x4a0
walk_component fs/namei.c:2000 [inline]
link_path_walk+0x60b/0xea0 fs/namei.c:2331
path_openat+0x24a/0x3280 fs/namei.c:3803
do_filp_open+0x235/0x490 fs/namei.c:3834
do_sys_openat2+0x13e/0x1d0 fs/open.c:1405
do_sys_open fs/open.c:1420 [inline]
__do_sys_openat fs/open.c:1436 [inline]
__se_sys_openat fs/open.c:1431 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1431
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8b7f9169a4
RSP: 002b:00007fffdadb9fc0 EFLAGS: 00000246
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f8b7f9169a4
RDX: 0000000000080000 RSI: 00007fffdadba0f8 RDI: 00000000ffffff9c
RBP: 00007fffdadba0f8 R08: 0000000000000008 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000
R13: 0000558fed691b42 R14: 0000000000000001 R15: 0000000000000000
</TASK>
INFO: task syz-executor167:5156 blocked for more than 144 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:21024 pid:5156 tgid:5156 ppid:5154 flags:0x00000002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_read_slowpath kernel/locking/rwsem.c:1086 [inline]
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x705/0xa40 kernel/locking/rwsem.c:1528
kernfs_dop_revalidate+0xd4/0x560 fs/kernfs/dir.c:1159
lookup_fast+0x1f4/0x4a0
walk_component fs/namei.c:2000 [inline]
link_path_walk+0x60b/0xea0 fs/namei.c:2331
path_openat+0x24a/0x3280 fs/namei.c:3803
do_filp_open+0x235/0x490 fs/namei.c:3834
do_sys_openat2+0x13e/0x1d0 fs/open.c:1405
do_sys_open fs/open.c:1420 [inline]
__do_sys_openat fs/open.c:1436 [inline]
__se_sys_openat fs/open.c:1431 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1431
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febd45d03e1
RSP: 002b:00007ffd172253b0 EFLAGS: 00000287 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007febd45d03e1
RDX: 0000000000090800 RSI: 00007febd461b14f RDI: 00000000ffffff9c
RBP: 0000000000000069 R08: 00000000095f7996 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffd1722543c
R13: 00007ffd17225450 R14: 00007ffd17225490 R15: 0000000000000067
</TASK>
INFO: task syz-executor167:5158 blocked for more than 145 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:19248 pid:5158 tgid:5158 ppid:5153 flags:0x00000002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_read_slowpath kernel/locking/rwsem.c:1086 [inline]
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x705/0xa40 kernel/locking/rwsem.c:1528
kernfs_dop_revalidate+0xd4/0x560 fs/kernfs/dir.c:1159
lookup_fast+0x1f4/0x4a0
walk_component fs/namei.c:2000 [inline]
link_path_walk+0x60b/0xea0 fs/namei.c:2331
path_openat+0x24a/0x3280 fs/namei.c:3803
do_filp_open+0x235/0x490 fs/namei.c:3834
do_sys_openat2+0x13e/0x1d0 fs/open.c:1405
do_sys_open fs/open.c:1420 [inline]
__do_sys_openat fs/open.c:1436 [inline]
__se_sys_openat fs/open.c:1431 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1431
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febd45d03e1
RSP: 002b:00007ffd172253b0 EFLAGS: 00000287
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007febd45d03e1
RDX: 0000000000090800 RSI: 00007febd461b14f RDI: 00000000ffffff9c
RBP: 000000000000006b R08: 000000002bee115c R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffd1722543c
R13: 00007ffd17225450 R14: 00007ffd17225490 R15: 0000000000000069
</TASK>
INFO: task syz-executor167:5157 blocked for more than 146 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:20512 pid:5157 tgid:5157 ppid:5151 flags:0x00000002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_read_slowpath kernel/locking/rwsem.c:1086 [inline]
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x705/0xa40 kernel/locking/rwsem.c:1528
kernfs_dop_revalidate+0xd4/0x560 fs/kernfs/dir.c:1159
lookup_fast+0x1f4/0x4a0
walk_component fs/namei.c:2000 [inline]
link_path_walk+0x60b/0xea0 fs/namei.c:2331
path_openat+0x24a/0x3280 fs/namei.c:3803
do_filp_open+0x235/0x490 fs/namei.c:3834
do_sys_openat2+0x13e/0x1d0 fs/open.c:1405
do_sys_open fs/open.c:1420 [inline]
__do_sys_openat fs/open.c:1436 [inline]
__se_sys_openat fs/open.c:1431 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1431
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febd45d03e1
RSP: 002b:00007ffd172253b0 EFLAGS: 00000287
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007febd45d03e1
RDX: 0000000000090800 RSI: 00007febd461b14f RDI: 00000000ffffff9c
RBP: 0000000000000068 R08: 000000000bbb6644 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffd1722543c
R13: 00007ffd17225450 R14: 00007ffd17225490 R15: 0000000000000066
</TASK>
INFO: task syz-executor167:5155 blocked for more than 147 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:21024 pid:5155 tgid:5155 ppid:5150 flags:0x00000002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_read_slowpath kernel/locking/rwsem.c:1086 [inline]
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x705/0xa40 kernel/locking/rwsem.c:1528
kernfs_dop_revalidate+0xd4/0x560 fs/kernfs/dir.c:1159
lookup_fast+0x1f4/0x4a0
walk_component fs/namei.c:2000 [inline]
link_path_walk+0x60b/0xea0 fs/namei.c:2331
path_openat+0x24a/0x3280 fs/namei.c:3803
do_filp_open+0x235/0x490 fs/namei.c:3834
do_sys_openat2+0x13e/0x1d0 fs/open.c:1405
do_sys_open fs/open.c:1420 [inline]
__do_sys_openat fs/open.c:1436 [inline]
__se_sys_openat fs/open.c:1431 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1431
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febd45d03e1
RSP: 002b:00007ffd172253b0 EFLAGS: 00000287
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007febd45d03e1
RDX: 0000000000090800 RSI: 00007febd461b14f RDI: 00000000ffffff9c
RBP: 000000000000006b R08: 0000000024e66dc2 R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffd1722543c
R13: 00007ffd17225450 R14: 00007ffd17225490 R15: 0000000000000069
</TASK>
INFO: task syz-executor167:5159 blocked for more than 148 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:21024 pid:5159 tgid:5159 ppid:5152 flags:0x00000002
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_read_slowpath kernel/locking/rwsem.c:1086 [inline]
__down_read_common kernel/locking/rwsem.c:1250 [inline]
__down_read kernel/locking/rwsem.c:1263 [inline]
down_read+0x705/0xa40 kernel/locking/rwsem.c:1528
kernfs_dop_revalidate+0xd4/0x560 fs/kernfs/dir.c:1159
lookup_fast+0x1f4/0x4a0
walk_component fs/namei.c:2000 [inline]
link_path_walk+0x60b/0xea0 fs/namei.c:2331
path_openat+0x24a/0x3280 fs/namei.c:3803
do_filp_open+0x235/0x490 fs/namei.c:3834
do_sys_openat2+0x13e/0x1d0 fs/open.c:1405
do_sys_open fs/open.c:1420 [inline]
__do_sys_openat fs/open.c:1436 [inline]
__se_sys_openat fs/open.c:1431 [inline]
__x64_sys_openat+0x247/0x2a0 fs/open.c:1431
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febd45d03e1
RSP: 002b:00007ffd172253b0 EFLAGS: 00000287
ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007febd45d03e1
RDX: 0000000000090800 RSI: 00007febd461b14f RDI: 00000000ffffff9c
RBP: 000000000000006b R08: 00000000128cac2c R09: 7fffffffffffffff
R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffd1722543c
R13: 00007ffd17225450 R14: 00007ffd17225490 R15: 0000000000000069
</TASK>
INFO: task kworker/0:5:5179 blocked for more than 149 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:5 state:D
stack:21328 pid:5179 tgid:5179 ppid:2 flags:0x00004000
Workqueue: usb_hub_wq hub_event

Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
__down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
kernfs_add_one+0x9a/0x8b0 fs/kernfs/dir.c:778
kernfs_create_dir_ns+0xd9/0x120 fs/kernfs/dir.c:1071
sysfs_create_dir_ns+0x189/0x3a0 fs/sysfs/dir.c:59
create_dir lib/kobject.c:73 [inline]
kobject_add_internal+0x435/0x8d0 lib/kobject.c:240
kobject_add_varg lib/kobject.c:374 [inline]
kobject_add+0x152/0x220 lib/kobject.c:426
device_add+0x4e5/0xbf0 drivers/base/core.c:3659
usb_new_device+0x104a/0x19a0 drivers/usb/core/hub.c:2651
hub_port_connect drivers/usb/core/hub.c:5521 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5661 [inline]
port_event drivers/usb/core/hub.c:5821 [inline]
hub_event+0x2d6a/0x5150 drivers/usb/core/hub.c:5903
process_one_work kernel/workqueue.c:3231 [inline]
process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312
worker_thread+0x86d/0xd70 kernel/workqueue.c:3393
kthread+0x2f0/0x390 kernel/kthread.c:389
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
INFO: task syz-executor167:5709 blocked for more than 150 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:26736 pid:5709 tgid:5709 ppid:5156 flags:0x00024006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
__down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
kernfs_remove_by_name_ns+0x7a/0x160 fs/kernfs/dir.c:1689
module_remove_driver+0x59/0x1c0 drivers/base/module.c:100
bus_remove_driver+0x1fb/0x320 drivers/base/bus.c:743
usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1733
raw_release+0xf9/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:462
__fput+0x406/0x8b0 fs/file_table.c:422
__do_sys_close fs/open.c:1555 [inline]
__se_sys_close fs/open.c:1540 [inline]
__x64_sys_close+0x7f/0x110 fs/open.c:1540
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febd45cf880
RSP: 002b:00007ffd17225418 EFLAGS: 00000202
ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007febd45cf880
RDX: 0000000000000000 RSI: 00007ffd17225380 RDI: 0000000000000004
RBP: 0000000000000000 R08: 000000000000000f R09: 00007ffd17225117
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd1722543c
R13: 00007ffd17225450 R14: 00007ffd17225490 R15: 0000000000000067
</TASK>
INFO: task syz-executor167:5710 blocked for more than 151 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:25488 pid:5710 tgid:5710 ppid:5157 flags:0x00024006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
__down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
kernfs_remove_by_name_ns+0x7a/0x160 fs/kernfs/dir.c:1689
remove_bind_files drivers/base/bus.c:600 [inline]
bus_remove_driver+0x26c/0x320 drivers/base/bus.c:738
usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1733
raw_release+0xf9/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:462
__fput+0x406/0x8b0 fs/file_table.c:422
__do_sys_close fs/open.c:1555 [inline]
__se_sys_close fs/open.c:1540 [inline]
__x64_sys_close+0x7f/0x110 fs/open.c:1540
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7febd45cf880
RSP: 002b:00007ffd17225418 EFLAGS: 00000202
ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007febd45cf880
RDX: 0000000000000000 RSI: 00007ffd17225380 RDI: 0000000000000004
RBP: 0000000000000000 R08: 000000000000000f R09: 00007ffd17225117
R10: 0000000000000000 R11: 0000000000000202 R12: 00007ffd1722543c
R13: 00007ffd17225450 R14: 00007ffd17225490 R15: 0000000000000066
</TASK>
INFO: task syz-executor167:5711 blocked for more than 152 seconds.
Not tainted 6.10.0-rc1-syzkaller-00027-g4a4be1ad3a6e #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor167 state:D
stack:25440 pid:5711 tgid:5711 ppid:5159 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5408 [inline]
__schedule+0x17e8/0x4a20 kernel/sched/core.c:6745
__schedule_loop kernel/sched/core.c:6822 [inline]
schedule+0x14b/0x320 kernel/sched/core.c:6837
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6894
rwsem_down_write_slowpath+0xeeb/0x13b0 kernel/locking/rwsem.c:1178
__down_write_common+0x1af/0x200 kernel/locking/rwsem.c:1306
kernfs_remove_by_name_ns+0x7a/0x160 fs/kernfs/dir.c:1689
remove_bind_files drivers/base/bus.c:600 [inline]
bus_remove_driver+0x26c/0x320 drivers/base/bus.c:738
usb_gadget_unregister_driver+0x4e/0x70 drivers/usb/gadget/udc/core.c:1733
raw_release+0xf9/0x1e0 drivers/usb/gadget/legacy/raw_gadget.c:462
__fput+0x406/0x8b0 fs/file_table.c:422
task_work_run+0x24f/0x310 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0xa27/0x27e0 kernel/exit.c:874
do_group_exit+0x207/0x2c0 kernel/exit.c:1023
get_signal+0x16a1/0x1740 kernel/signal.c:2909


---
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