INFO: task kworker/0:8:18462 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc8+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
kworker/0:8     D28680 18462      2 0x80004000
Workqueue: events linkwatch_event
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 schedule_preempt_disabled+0x13/0x20 kernel/sched/core.c:4006
 __mutex_lock_common kernel/locking/mutex.c:1007 [inline]
 __mutex_lock+0x7b0/0x13c0 kernel/locking/mutex.c:1077
 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1092
 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:72
 linkwatch_event+0xf/0x70 net/core/link_watch.c:242
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
INFO: task syz-executor.2:23868 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc8+ #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D27224 23868  10397 0x00004004
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xd9/0x260 kernel/sched/core.c:3947
 exp_funnel_lock kernel/rcu/tree_exp.h:308 [inline]
 synchronize_rcu_expedited+0x544/0x5b0 kernel/rcu/tree_exp.h:816
 synchronize_net+0x3b/0x60 net/core/dev.c:9264
 rollback_registered_many+0xa37/0xdd0 net/core/dev.c:8232
 rollback_registered+0x109/0x1d0 net/core/dev.c:8243
 unregister_netdevice_queue net/core/dev.c:9290 [inline]
 unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9283
 unregister_netdevice include/linux/netdevice.h:2631 [inline]
 __tun_detach+0xd8a/0x1040 drivers/net/tun.c:723
 tun_detach drivers/net/tun.c:740 [inline]
 tun_chr_close+0xe0/0x180 drivers/net/tun.c:3442
 __fput+0x2ff/0x890 fs/file_table.c:280
 ____fput+0x16/0x20 fs/file_table.c:313
 task_work_run+0x145/0x1c0 kernel/task_work.c:113
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:163
 prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
 do_syscall_64+0x5a9/0x6a0 arch/x86/entry/common.c:299
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4135d1
Code: 49 89 c9 48 85 d2 0f 84 e3 02 00 00 44 0f b6 32 48 ff c2 b9 08 00 00 00 49 39 f5 0f 85 9c 02 00 00 48 8b 73 08 48 c1 ee 03 48 <85> f6 0f 84 fc 03 00 00 48 83 fe 02 0f 83 79 02 00 00 bb 02 00 00
RSP: 002b:00007ffcef533580 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00000000004135d1
RDX: 0000001b2d820000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 0000000000000001 R08: 000000008336f29a R09: 000000008336f29e
R10: 00007ffcef533660 R11: 0000000000000293 R12: 000000000075bf20
R13: 000000000005e560 R14: 0000000000761038 R15: ffffffffffffffff
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 5.3.0-rc8+ #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+0x172/0x1f0 lib/dump_stack.c:113
 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62
 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:205 [inline]
 watchdog+0x9d0/0xef0 kernel/hung_task.c:289
 kthread+0x361/0x430 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: 10898 Comm: kworker/u4:5 Not tainted 5.3.0-rc8+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:trace_lock_release include/trace/events/lock.h:58 [inline]
RIP: 0010:lock_release+0x599/0x960 kernel/locking/lockdep.c:4430
Code: 03 00 00 49 8b 0f 49 bf 00 00 00 00 00 fc ff df 48 8d 78 08 48 89 fa 48 c1 ea 03 42 80 3c 3a 00 0f 85 3d 02 00 00 48 8b 78 08 <48> 89 85 50 ff ff ff 4c 89 ea 4c 89 e6 ff d1 48 8b 85 50 ff ff ff
RSP: 0018:ffff8880523b7c00 EFLAGS: 00000046
RAX: ffff888092d75d10 RBX: 1ffff1100a476f85 RCX: ffffffff8157e3c0
RDX: 1ffff110125aeba3 RSI: 0000000000000008 RDI: ffffffff88d93b40
RBP: ffff8880523b7cd0 R08: 1ffffffff134afaf R09: fffffbfff134afb0
R10: fffffbfff134afaf R11: ffffffff89a57d7f R12: ffffffff88dac3c0
R13: ffffffff8721f86a R14: ffff8880523b7ca8 R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000c438443000 CR3: 000000008f712000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 rcu_lock_release include/linux/rcupdate.h:213 [inline]
 rcu_read_unlock include/linux/rcupdate.h:646 [inline]
 batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:411 [inline]
 batadv_nc_worker+0x225/0x760 net/batman-adv/network-coding.c:718
 process_one_work+0x9af/0x1740 kernel/workqueue.c:2269
 worker_thread+0x98/0xe40 kernel/workqueue.c:2415
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352