INFO: task kworker/0:0:5 blocked for more than 143 seconds. Not tainted 5.4.0-rc6-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. kworker/0:0 D26016 5 2 0x80004000 Workqueue: usb_hub_wq hub_event Call Trace: schedule+0xca/0x250 kernel/sched/core.c:4136 schedule_timeout+0x682/0xb20 kernel/time/timer.c:1871 do_wait_for_common kernel/sched/completion.c:83 [inline] __wait_for_common kernel/sched/completion.c:104 [inline] wait_for_common kernel/sched/completion.c:115 [inline] wait_for_completion+0x26f/0x3c0 kernel/sched/completion.c:136 kthread_stop+0x10c/0x610 kernel/kthread.c:559 hwrng_unregister+0x190/0x210 drivers/char/hw_random/core.c:538 chaoskey_disconnect+0x1b2/0x200 drivers/usb/misc/chaoskey.c:232 usb_unbind_interface+0x1bd/0x8a0 drivers/usb/core/driver.c:423 __device_release_driver drivers/base/dd.c:1134 [inline] device_release_driver_internal+0x42f/0x500 drivers/base/dd.c:1165 bus_remove_device+0x2dc/0x4a0 drivers/base/bus.c:532 device_del+0x420/0xb20 drivers/base/core.c:2376 usb_disable_device+0x211/0x690 drivers/usb/core/message.c:1237 usb_disconnect+0x284/0x8d0 drivers/usb/core/hub.c:2200 hub_port_connect drivers/usb/core/hub.c:5035 [inline] hub_port_connect_change drivers/usb/core/hub.c:5324 [inline] port_event drivers/usb/core/hub.c:5470 [inline] hub_event+0x16f2/0x3800 drivers/usb/core/hub.c:5552 process_one_work+0x92b/0x1530 kernel/workqueue.c:2269 worker_thread+0x96/0xe20 kernel/workqueue.c:2415 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Showing all locks held in the system: 5 locks held by kworker/0:0/5: #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881da1dfdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: ffff8881d516f200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #2: ffff8881d516f200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498 #3: ffff8881cf6c4200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #3: ffff8881cf6c4200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881cf6c5190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 5 locks held by kworker/0:1/12: 5 locks held by kworker/1:0/17: #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881da267dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: ffff8881d5168200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #2: ffff8881d5168200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498 #3: ffff8881cdc82200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #3: ffff8881cdc82200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881cdc84190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 1 lock held by khungtaskd/23: #0: ffffffff86cfe8a0 (rcu_read_lock){....}, at: debug_show_all_locks+0x53/0x269 kernel/locking/lockdep.c:5335 5 locks held by kworker/1:2/83: #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881d89efdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: ffff8881d50e3200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #2: ffff8881d50e3200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498 #3: ffff8881ce29d200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #3: ffff8881ce29d200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881ce29e190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 1 lock held by rsyslogd/1601: 2 locks held by getty/1691: #0: ffff8881d1997090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000046b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1692: #0: ffff8881d14ab090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000048f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1693: #0: ffff8881d2ee5090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc900004872e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1694: #0: ffff8881d1b74090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000047f2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1695: #0: ffff8881d14aa090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000048b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1696: #0: ffff8881d1b73090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000047b2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 2 locks held by getty/1697: #0: ffff8881d1990090 (&tty->ldisc_sem){++++}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:272 #1: ffffc9000045d2e0 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0x223/0x1ae0 drivers/tty/n_tty.c:2156 5 locks held by kworker/1:1/1734: #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881d91ffdd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: ffff8881d5141200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #2: ffff8881d5141200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498 #3: ffff8881cec95200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #3: ffff8881cec95200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881cec97190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 5 locks held by kworker/1:4/1739: #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: __write_once_size include/linux/compiler.h:226 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic64_set include/asm-generic/atomic-instrumented.h:855 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: atomic_long_set include/asm-generic/atomic-long.h:40 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_data kernel/workqueue.c:620 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: set_work_pool_and_clear_pending kernel/workqueue.c:647 [inline] #0: ffff8881d8efd528 ((wq_completion)usb_hub_wq){+.+.}, at: process_one_work+0x827/0x1530 kernel/workqueue.c:2240 #1: ffff8881cf597dd0 ((work_completion)(&hub->events)){+.+.}, at: process_one_work+0x85b/0x1530 kernel/workqueue.c:2244 #2: ffff8881d519e200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #2: ffff8881d519e200 (&dev->mutex){....}, at: hub_event+0x1b2/0x3800 drivers/usb/core/hub.c:5498 #3: ffff8881cd884200 (&dev->mutex){....}, at: device_lock include/linux/device.h:1462 [inline] #3: ffff8881cd884200 (&dev->mutex){....}, at: usb_disconnect+0x91/0x8d0 drivers/usb/core/hub.c:2191 #4: ffff8881cd885190 (&dev->mutex){....}, at: device_release_driver_internal+0x23/0x500 drivers/base/dd.c:1162 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 23 Comm: khungtaskd Not tainted 5.4.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xca/0x13e lib/dump_stack.c:113 nmi_cpu_backtrace.cold+0x55/0x96 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b0/0x1c7 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline] watchdog+0x9a4/0xe50 kernel/hung_task.c:289 kthread+0x318/0x420 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1719 Comm: sshd Not tainted 5.4.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:ipt_do_table+0x259/0x1280 net/ipv4/netfilter/ip_tables.c:258 Code: c1 ea 03 83 e0 0f c1 e0 02 89 84 24 e4 00 00 00 48 b8 00 00 00 00 00 fc ff df 0f b6 04 02 84 c0 74 08 3c 03 0f 8e a0 0e 00 00 <44> 89 e1 bb 01 00 00 00 31 ff d3 e3 23 5d 10 89 de e8 a1 2e 55 fc RSP: 0018:ffff8881c65af350 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8881c65af5a0 RCX: ffff8881ca5ca414 RDX: 1ffff1103aa41f92 RSI: ffffffff84e8f869 RDI: ffff8881d520fc90 RBP: ffff8881d520fc80 R08: ffff8881d07fc800 R09: ffffed103b66658d R10: ffffed103b66658c R11: ffff8881db332c63 R12: 0000000000000003 R13: ffff8881d54b2000 R14: ffff8881c65af5c0 R15: ffff8881c922c8dc FS: 00007f6fd12b57c0(0000) GS:ffff8881db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ff9e84d4000 CR3: 00000001d2360000 CR4: 00000000001406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ipt_mangle_out net/ipv4/netfilter/iptable_mangle.c:56 [inline] iptable_mangle_hook+0x21f/0x510 net/ipv4/netfilter/iptable_mangle.c:81 nf_hook_entry_hookfn include/linux/netfilter.h:135 [inline] nf_hook_slow+0xba/0x1e0 net/netfilter/core.c:512 nf_hook include/linux/netfilter.h:260 [inline] __ip_local_out+0x30f/0x5e0 net/ipv4/ip_output.c:114 ip_local_out+0x26/0x1a0 net/ipv4/ip_output.c:123 __ip_queue_xmit+0x85c/0x1c20 net/ipv4/ip_output.c:532 __tcp_transmit_skb+0x1940/0x34f0 net/ipv4/tcp_output.c:1169 tcp_transmit_skb net/ipv4/tcp_output.c:1185 [inline] tcp_write_xmit+0xe48/0x57d0 net/ipv4/tcp_output.c:2440 __tcp_push_pending_frames+0xaa/0x330 net/ipv4/tcp_output.c:2616 tcp_push+0x468/0x6e0 net/ipv4/tcp.c:726 tcp_sendmsg_locked+0x273a/0x3020 net/ipv4/tcp.c:1405 tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1436 inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:657 sock_write_iter+0x235/0x360 net/socket.c:989 call_write_iter include/linux/fs.h:1895 [inline] new_sync_write+0x420/0x650 fs/read_write.c:483 __vfs_write+0xc9/0x100 fs/read_write.c:496 vfs_write+0x262/0x5c0 fs/read_write.c:558 ksys_write+0x127/0x250 fs/read_write.c:611 do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f6fcf650370 Code: 73 01 c3 48 8b 0d c8 4a 2b 00 31 d2 48 29 c2 64 89 11 48 83 c8 ff eb ea 90 90 83 3d 85 a2 2b 00 00 75 10 b8 01 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 0e 8a 01 00 48 89 04 24 RSP: 002b:00007fff5d86cac8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000038 RCX: 00007f6fcf650370 RDX: 0000000000000038 RSI: 0000560719a27480 RDI: 0000000000000003 RBP: 0000560719a27480 R08: 0000000000000001 R09: 0101010101010101 R10: 0000000000000008 R11: 0000000000000246 R12: 00007fff5d86cb2c R13: 0000560718311fb4 R14: 0000000000000028 R15: 0000560718313ca0