[v5.15] INFO: task hung in hwrng_register

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: abddfcf701a5 Linux 5.15.99
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=145b8692c80000
kernel config: https://syzkaller.appspot.com/x/.config?x=e8038112e99511e7
dashboard link: https://syzkaller.appspot.com/bug?extid=33da9c3d7e9cf8614979
compiler: Debian clang version 15.0.7, GNU ld (GNU Binutils for Debian) 2.35.2

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5d41fec63ff8/disk-abddfcf7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/69db433dc01f/vmlinux-abddfcf7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a00e1270bd95/bzImage-abddfcf7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+33da9c...@syzkaller.appspotmail.com

INFO: task kworker/1:0:21 blocked for more than 144 seconds.
Not tainted 5.15.99-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:0 state:D stack:22328 pid: 21 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5023 [inline]
__schedule+0x1348/0x4610 kernel/sched/core.c:6369
schedule+0x11b/0x1f0 kernel/sched/core.c:6452
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6511
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
chaoskey_probe+0x79d/0xb40 drivers/usb/misc/chaoskey.c:205
usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_new_device+0xc17/0x18d0 drivers/usb/core/hub.c:2568
hub_port_connect drivers/usb/core/hub.c:5358 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
port_event drivers/usb/core/hub.c:5648 [inline]
hub_event+0x2dd8/0x56d0 drivers/usb/core/hub.c:5730
process_one_work+0x90d/0x1270 kernel/workqueue.c:2306
worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298
</TASK>
INFO: task kworker/0:2:1064 blocked for more than 145 seconds.
Not tainted 5.15.99-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:2 state:D stack:22112 pid: 1064 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5023 [inline]
__schedule+0x1348/0x4610 kernel/sched/core.c:6369
schedule+0x11b/0x1f0 kernel/sched/core.c:6452
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6511
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
chaoskey_probe+0x79d/0xb40 drivers/usb/misc/chaoskey.c:205
usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_new_device+0xc17/0x18d0 drivers/usb/core/hub.c:2568
hub_port_connect drivers/usb/core/hub.c:5358 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
port_event drivers/usb/core/hub.c:5648 [inline]
hub_event+0x2dd8/0x56d0 drivers/usb/core/hub.c:5730
process_one_work+0x90d/0x1270 kernel/workqueue.c:2306
worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298
</TASK>
INFO: task kworker/1:2:1067 blocked for more than 145 seconds.
Not tainted 5.15.99-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:2 state:D stack:22456 pid: 1067 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5023 [inline]
__schedule+0x1348/0x4610 kernel/sched/core.c:6369
schedule+0x11b/0x1f0 kernel/sched/core.c:6452
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6511
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
chaoskey_probe+0x79d/0xb40 drivers/usb/misc/chaoskey.c:205
usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_new_device+0xc17/0x18d0 drivers/usb/core/hub.c:2568
hub_port_connect drivers/usb/core/hub.c:5358 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
port_event drivers/usb/core/hub.c:5648 [inline]
hub_event+0x2dd8/0x56d0 drivers/usb/core/hub.c:5730
process_one_work+0x90d/0x1270 kernel/workqueue.c:2306
worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298
</TASK>
INFO: task kworker/0:8:3731 blocked for more than 146 seconds.
Not tainted 5.15.99-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:8 state:D stack:22232 pid: 3731 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5023 [inline]
__schedule+0x1348/0x4610 kernel/sched/core.c:6369
schedule+0x11b/0x1f0 kernel/sched/core.c:6452
schedule_timeout+0xac/0x300 kernel/time/timer.c:1860
do_wait_for_common+0x2d9/0x480 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+0x48/0x60 kernel/sched/completion.c:138
cleanup_rng drivers/char/hw_random/core.c:82 [inline]
kref_put include/linux/kref.h:65 [inline]
drop_current_rng+0x8b/0xf0 drivers/char/hw_random/core.c:110
set_current_rng+0x3ad/0x530 drivers/char/hw_random/core.c:97
hwrng_register+0x34a/0x4c0 drivers/char/hw_random/core.c:500
chaoskey_probe+0x79d/0xb40 drivers/usb/misc/chaoskey.c:205
usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_new_device+0xc17/0x18d0 drivers/usb/core/hub.c:2568
hub_port_connect drivers/usb/core/hub.c:5358 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
port_event drivers/usb/core/hub.c:5648 [inline]
hub_event+0x2dd8/0x56d0 drivers/usb/core/hub.c:5730
process_one_work+0x90d/0x1270 kernel/workqueue.c:2306
worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298
</TASK>
INFO: task kworker/0:9:7004 blocked for more than 147 seconds.
Not tainted 5.15.99-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:9 state:D stack:22104 pid: 7004 ppid: 2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5023 [inline]
__schedule+0x1348/0x4610 kernel/sched/core.c:6369
schedule+0x11b/0x1f0 kernel/sched/core.c:6452
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6511
__mutex_lock_common+0xe34/0x25a0 kernel/locking/mutex.c:669
__mutex_lock kernel/locking/mutex.c:729 [inline]
mutex_lock_nested+0x17/0x20 kernel/locking/mutex.c:743
hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
chaoskey_probe+0x79d/0xb40 drivers/usb/misc/chaoskey.c:205
usb_probe_interface+0x5c0/0xaf0 drivers/usb/core/driver.c:396
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_set_configuration+0x19dd/0x2020 drivers/usb/core/message.c:2170
usb_generic_driver_probe+0x84/0x140 drivers/usb/core/generic.c:238
usb_probe_device+0x130/0x260 drivers/usb/core/driver.c:293
really_probe+0x24e/0xb60 drivers/base/dd.c:595
__driver_probe_device+0x1c3/0x3f0 drivers/base/dd.c:750
driver_probe_device+0x50/0x420 drivers/base/dd.c:780
__device_attach_driver+0x2b9/0x500 drivers/base/dd.c:902
bus_for_each_drv+0x183/0x200 drivers/base/bus.c:427
__device_attach+0x359/0x570 drivers/base/dd.c:974
bus_probe_device+0xba/0x1e0 drivers/base/bus.c:487
device_add+0xb48/0xfd0 drivers/base/core.c:3394
usb_new_device+0xc17/0x18d0 drivers/usb/core/hub.c:2568
hub_port_connect drivers/usb/core/hub.c:5358 [inline]
hub_port_connect_change drivers/usb/core/hub.c:5502 [inline]
port_event drivers/usb/core/hub.c:5648 [inline]
hub_event+0x2dd8/0x56d0 drivers/usb/core/hub.c:5730
process_one_work+0x90d/0x1270 kernel/workqueue.c:2306
worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298
</TASK>

Showing all locks held in the system:
3 locks held by kworker/0:1/13:
#0: ffff888011c64d38 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc90000d27d20 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
#2: ffff888046362240 (&data->fib_lock){+.+.}-{3:3}, at: nsim_fib_event_work+0x2cd/0x4120 drivers/net/netdevsim/fib.c:1478
6 locks held by kworker/1:0/21:
#0: ffff888141f97138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc90000db7d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
#2: ffff888147c58220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888147c58220 (&dev->mutex){....}-{3:3}, at: hub_event+0x207/0x56d0 drivers/usb/core/hub.c:5676
#3: ffff88801f109220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff88801f109220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#4: ffff8880143b91a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff8880143b91a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#5: ffffffff8cff3288 (rng_mutex){+.+.}-{3:3}, at: hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
1 lock held by khungtaskd/27:
#0: ffffffff8c91c2a0 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0x0/0x30
5 locks held by kworker/u4:2/151:
#0: ffff888011db5138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc90001b3fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
#2: ffffffff8d9cd190 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf1/0xb60 net/core/net_namespace.c:558
#3: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: ip6gre_exit_batch_net+0xc0/0x460 net/ipv6/ip6_gre.c:1640
#4: ffffffff8c9207e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:290 [inline]
#4: ffffffff8c9207e8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x280/0x740 kernel/rcu/tree_exp.h:840
1 lock held by hwrng/899:
#0: ffffffff8cff3288 (rng_mutex){+.+.}-{3:3}, at: get_current_rng drivers/char/hw_random/core.c:127 [inline]
#0: ffffffff8cff3288 (rng_mutex){+.+.}-{3:3}, at: hwrng_fillfn+0x36/0x280 drivers/char/hw_random/core.c:433
6 locks held by kworker/0:2/1064:
#0: ffff888141f97138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc900042d7d20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
#2: ffff88801ed60220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff88801ed60220 (&dev->mutex){....}-{3:3}, at: hub_event+0x207/0x56d0 drivers/usb/core/hub.c:5676
#3: ffff888046e94220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff888046e94220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#4: ffff888045af71a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff888045af71a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#5: ffffffff8cff3288 (rng_mutex){+.+.}-{3:3}, at: hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
6 locks held by kworker/1:2/1067:
#0: ffff888141f97138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc900043efd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
#2: ffff888147cf8220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888147cf8220 (&dev->mutex){....}-{3:3}, at: hub_event+0x207/0x56d0 drivers/usb/core/hub.c:5676
#3: ffff8880791f8220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff8880791f8220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#4: ffff888079a301a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff888079a301a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#5: ffffffff8cff3288 (rng_mutex){+.+.}-{3:3}, at: hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
2 locks held by getty/3267:
#0: ffff888024483098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252
#1: ffffc90002bb32e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6af/0x1da0 drivers/tty/n_tty.c:2147
2 locks held by kworker/1:6/3672:
#0: ffff888011c66538 ((wq_completion)rcu_gp){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc9000306fd20 ((work_completion)(&rew.rew_work)){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
6 locks held by kworker/0:8/3731:
#0: ffff888141f97138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc9000310fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
#2: ffff88801ec30220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff88801ec30220 (&dev->mutex){....}-{3:3}, at: hub_event+0x207/0x56d0 drivers/usb/core/hub.c:5676
#3: ffff888046e91220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff888046e91220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#4: ffff888045af61a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff888045af61a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#5: ffffffff8cff3288 (rng_mutex){+.+.}-{3:3}, at: hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
3 locks held by kworker/u4:11/4199:
6 locks held by kworker/0:9/7004:
#0: ffff888141f97138 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x794/0x1270 kernel/workqueue.c:2279
#1: ffffc9000408fd20 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x7da/0x1270 kernel/workqueue.c:2281
#2: ffff888147d08220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#2: ffff888147d08220 (&dev->mutex){....}-{3:3}, at: hub_event+0x207/0x56d0 drivers/usb/core/hub.c:5676
#3: ffff888046e95220 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#3: ffff888046e95220 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#4: ffff888045af11a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:760 [inline]
#4: ffff888045af11a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x8a/0x570 drivers/base/dd.c:949
#5: ffffffff8cff3288 (rng_mutex){+.+.}-{3:3}, at: hwrng_register+0xa9/0x4c0 drivers/char/hw_random/core.c:473
4 locks held by udevd/9593:
#0: ffff88806bcce418 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182
#1: ffff888069265088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x50/0x3b0 fs/kernfs/file.c:112
#2: ffff888076fe8da0 (kn->active#89){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x3b0 fs/kernfs/file.c:113
#3: ffff888046e91220 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:765 [inline]
#3: ffff888046e91220 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x22/0x90 drivers/usb/core/sysfs.c:141
4 locks held by udevd/9630:
#0: ffff88801a39b668 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182
#1: ffff888076e6c088 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x50/0x3b0 fs/kernfs/file.c:112
#2: ffff888072437918 (kn->active#89){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x3b0 fs/kernfs/file.c:113
#3: ffff888046e95220 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:765 [inline]
#3: ffff888046e95220 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x22/0x90 drivers/usb/core/sysfs.c:141
4 locks held by udevd/9661:
#0: ffff8880775b1e80 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182
#1: ffff888074696c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x50/0x3b0 fs/kernfs/file.c:112
#2: ffff888072669490 (kn->active#89){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x3b0 fs/kernfs/file.c:113
#3: ffff8880791f8220 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:765 [inline]
#3: ffff8880791f8220 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x22/0x90 drivers/usb/core/sysfs.c:141
4 locks held by udevd/9982:
#0: ffff88801a39b0a0 (&p->lock){+.+.}-{3:3}, at: seq_read_iter+0xae/0xd10 fs/seq_file.c:182
#1: ffff88801f822c88 (&of->mutex){+.+.}-{3:3}, at: kernfs_seq_start+0x50/0x3b0 fs/kernfs/file.c:112
#2: ffff8880197cc490 (kn->active#89){++++}-{0:0}, at: kernfs_seq_start+0x6f/0x3b0 fs/kernfs/file.c:113
#3: ffff88801f109220 (&dev->mutex){....}-{3:3}, at: device_lock_interruptible include/linux/device.h:765 [inline]
#3: ffff88801f109220 (&dev->mutex){....}-{3:3}, at: manufacturer_show+0x22/0x90 drivers/usb/core/sysfs.c:141
1 lock held by syz-executor.0/16085:
#0: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5584
1 lock held by syz-executor.0/16089:
#0: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:72 [inline]
#0: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x94c/0xee0 net/core/rtnetlink.c:5584
1 lock held by syz-executor.1/16094:
#0: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: __tun_chr_ioctl+0x475/0x2340 drivers/net/tun.c:3045
2 locks held by syz-executor.4/16095:
#0: ffffffff8d9cd190 (pernet_ops_rwsem){++++}-{3:3}, at: copy_net_ns+0x37b/0x5d0 net/core/net_namespace.c:469
#1: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_create_pnetids_list net/smc/smc_pnet.c:799 [inline]
#1: ffffffff8d9d8ee8 (rtnl_mutex){+.+.}-{3:3}, at: smc_pnet_net_init+0x176/0x3b0 net/smc/smc_pnet.c:868

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.99-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:210 [inline]
watchdog+0xf54/0xfa0 kernel/hung_task.c:295
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 4148 Comm: kworker/u4:8 Not tainted 5.15.99-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023
Workqueue: bat_events batadv_nc_worker
RIP: 0010:hlock_class kernel/locking/lockdep.c:192 [inline]
RIP: 0010:check_wait_context kernel/locking/lockdep.c:4686 [inline]
RIP: 0010:__lock_acquire+0x52c/0x1ff0 kernel/locking/lockdep.c:4961
Code: 89 d8 48 c1 e8 03 0f b6 04 10 84 c0 0f 85 b1 12 00 00 44 0f b6 33 48 8b 44 24 38 0f b6 04 10 84 c0 0f 85 c0 12 00 00 41 8b 1f <81> e3 ff 1f 00 00 89 d8 c1 e8 06 48 8d 3c c5 a0 30 bb 8f be 08 00
RSP: 0018:ffffc900030cf9a0 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000020028 RCX: ffffffff8162cf3b
RDX: dffffc0000000000 RSI: 0000000000000008 RDI: ffffffff8fbb30a0
RBP: 000000000000000a R08: dffffc0000000000 R09: fffffbfff1f76615
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000002
R13: ffff888044f70a18 R14: 0000000000000002 R15: ffff888044f70a90
FS: 0000000000000000(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f161a4251b8 CR3: 00000000483cb000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
lock_acquire+0x1ff/0x570 kernel/locking/lockdep.c:5622
rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:269
rcu_read_lock include/linux/rcupdate.h:696 [inline]
batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:412 [inline]
batadv_nc_worker+0xc1/0x5b0 net/batman-adv/network-coding.c:723
process_one_work+0x90d/0x1270 kernel/workqueue.c:2306
worker_thread+0xaca/0x1280 kernel/workqueue.c:2453
kthread+0x3f6/0x4f0 kernel/kthread.c:319
ret_from_fork+0x1f/0x30 <unknown>:298
</TASK>


---
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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.