syzbot

INFO: task kworker/1:0:19 blocked for more than 143 seconds.
      Not tainted 5.11.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:0     state:D stack:25024 pid:   19 ppid:     2 flags:0x00004000
Workqueue: usb_hub_wq hub_event
Call Trace:
 context_switch kernel/sched/core.c:4327 [inline]
 __schedule+0x90c/0x21a0 kernel/sched/core.c:5078
 schedule+0xcf/0x270 kernel/sched/core.c:5157
 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1854
 do_wait_for_common kernel/sched/completion.c:85 [inline]
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x163/0x260 kernel/sched/completion.c:138
 virtio_cleanup+0x80/0xa0 drivers/char/hw_random/virtio-rng.c:85
 cleanup_rng drivers/char/hw_random/core.c:81 [inline]
 kref_put include/linux/kref.h:65 [inline]
 drop_current_rng+0xda/0x110 drivers/char/hw_random/core.c:109
 set_current_rng+0x2d3/0x490 drivers/char/hw_random/core.c:96
 hwrng_register+0x3bf/0x600 drivers/char/hw_random/core.c:505
 chaoskey_probe+0x886/0xc50 drivers/usb/misc/chaoskey.c:205
 usb_probe_interface+0x315/0x7f0 drivers/usb/core/driver.c:396
 really_probe+0x291/0xe60 drivers/base/dd.c:554
 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:740
 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:846
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431
 __device_attach+0x228/0x4a0 drivers/base/dd.c:914
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0xbc4/0x1d90 drivers/base/core.c:3109
 usb_set_configuration+0x113c/0x1910 drivers/usb/core/message.c:2164
 usb_generic_driver_probe+0xba/0x100 drivers/usb/core/generic.c:238
 usb_probe_device+0xd9/0x2c0 drivers/usb/core/driver.c:293
 really_probe+0x291/0xe60 drivers/base/dd.c:554
 driver_probe_device+0x26b/0x3d0 drivers/base/dd.c:740
 __device_attach_driver+0x1d1/0x290 drivers/base/dd.c:846
 bus_for_each_drv+0x15f/0x1e0 drivers/base/bus.c:431
 __device_attach+0x228/0x4a0 drivers/base/dd.c:914
 bus_probe_device+0x1e4/0x290 drivers/base/bus.c:491
 device_add+0xbc4/0x1d90 drivers/base/core.c:3109
 usb_new_device.cold+0x721/0x1058 drivers/usb/core/hub.c:2555
 hub_port_connect drivers/usb/core/hub.c:5223 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5363 [inline]
 port_event drivers/usb/core/hub.c:5509 [inline]
 hub_event+0x2357/0x4320 drivers/usb/core/hub.c:5591
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Showing all locks held in the system:
6 locks held by kworker/1:0/19:
 #0: ffff888015b50d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888015b50d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic64_set include/asm-generic/atomic-instrumented.h:856 [inline]
 #0: ffff888015b50d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: atomic_long_set include/asm-generic/atomic-long.h:41 [inline]
 #0: ffff888015b50d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:616 [inline]
 #0: ffff888015b50d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:643 [inline]
 #0: ffff888015b50d38 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_one_work+0x871/0x15f0 kernel/workqueue.c:2246
 #1: ffffc90000d97da8 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x8a5/0x15f0 kernel/workqueue.c:2250
 #2: ffff88801cd41218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:737 [inline]
 #2: ffff88801cd41218 (&dev->mutex){....}-{3:3}, at: hub_event+0x1c1/0x4320 drivers/usb/core/hub.c:5537
 #3: ffff888025a2c218 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:737 [inline]
 #3: ffff888025a2c218 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:889
 #4: ffff888025a2a1a8 (&dev->mutex){....}-{3:3}, at: device_lock include/linux/device.h:737 [inline]
 #4: ffff888025a2a1a8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x7a/0x4a0 drivers/base/dd.c:889
 #5: ffffffff8c758108 (rng_mutex){+.+.}-{3:3}, at: hwrng_register+0x7a/0x600 drivers/char/hw_random/core.c:478
1 lock held by khungtaskd/1659:
 #0: ffffffff8bd73da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6259
1 lock held by in:imklog/8168:
 #0: ffff8880220a1c70 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:947

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

NMI backtrace for cpu 1
CPU: 1 PID: 1659 Comm: khungtaskd Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 nmi_cpu_backtrace.cold+0x44/0xd7 lib/nmi_backtrace.c:105
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd43/0xfa0 kernel/hung_task.c:294
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 4876 Comm: systemd-journal Not tainted 5.11.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:exit_to_user_mode_prepare+0xae/0x250 kernel/entry/common.c:198
Code: 74 18 65 8b 05 f3 c4 a0 7e 85 c0 75 0d 65 8b 05 e4 c1 a0 7e 85 c0 74 02 0f 0b 5b 5d 41 5c e9 59 cb f7 ff 65 8b 05 ce c1 a0 7e <85> c0 0f 84 72 ff ff ff 0f 0b f7 c3 0e 30 02 00 0f 84 70 ff ff ff
RSP: 0018:ffffc9000161ff28 EFLAGS: 00000046
RAX: 0000000000000000 RBX: 0000000000004002 RCX: 0000000000000000
RDX: ffff88801299b780 RSI: ffffffff88fa9dc4 RDI: 0000000000000001
RBP: ffffc9000161ff58 R08: 0000000000000000 R09: 0000000000000001
R10: ffffffff8178a39d R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS:  00007fd10644e8c0(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd103827000 CR3: 000000001209b000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 __syscall_exit_to_user_mode_work kernel/entry/common.c:283 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7fd1059dd840
Code: 73 01 c3 48 8b 0d 68 77 20 00 f7 d8 64 89 01 48 83 c8 ff c3 66 0f 1f 44 00 00 83 3d 89 bb 20 00 00 75 10 b8 02 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 1e f6 ff ff 48 89 04 24
RSP: 002b:00007ffe2d2a2418 EFLAGS: 00000246 ORIG_RAX: 0000000000000002
RAX: fffffffffffffffe RBX: 00007ffe2d2a2720 RCX: 00007fd1059dd840
RDX: 00000000000001a0 RSI: 0000000000080042 RDI: 0000562ecefdf820
RBP: 000000000000000d R08: 000000000000c0ff R09: 00000000ffffffff
R10: 0000000000000069 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000562ecefd4040 R14: 00007ffe2d2a26e0 R15: 0000562ecefdf370