INFO: task syz-executor.0:2350 blocked for more than 143 seconds.
      Not tainted 5.3.0-rc3+ #160
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.0  D28920  2350  10362 0x80004002
Call Trace:
 context_switch kernel/sched/core.c:3254 [inline]
 __schedule+0x755/0x1580 kernel/sched/core.c:3880
 schedule+0xa8/0x270 kernel/sched/core.c:3944
 rwsem_down_write_slowpath+0x708/0xf60 kernel/locking/rwsem.c:1214
 __down_write kernel/locking/rwsem.c:1365 [inline]
 down_write+0x13c/0x150 kernel/locking/rwsem.c:1501
 unregister_netdevice_notifier+0x7e/0x390 net/core/dev.c:1713
 bcm_release+0x93/0x5e0 net/can/bcm.c:1525
 __sock_release+0xce/0x280 net/socket.c:590
 sock_close+0x1e/0x30 net/socket.c:1268
 __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
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x92f/0x2e50 kernel/exit.c:879
 do_group_exit+0x135/0x360 kernel/exit.c:983
 get_signal+0x47c/0x2500 kernel/signal.c:2729
 do_signal+0x87/0x1700 arch/x86/kernel/signal.c:815
 exit_to_usermode_loop+0x286/0x380 arch/x86/entry/common.c:159
 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: 0033:0x459829
Code: Bad RIP value.
RSP: 002b:00007fadc2e09c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000029
RAX: 0000000000000003 RBX: 0000000000000003 RCX: 0000000000459829
RDX: 0000000000000002 RSI: 0000000000000002 RDI: 000000000000001d
RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fadc2e0a6d4
R13: 00000000004c846b R14: 00000000004defe0 R15: 00000000ffffffff
INFO: lockdep is turned off.
NMI backtrace for cpu 0
CPU: 0 PID: 1057 Comm: khungtaskd Not tainted 5.3.0-rc3+ #160
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: 21 Comm: kworker/u4:1 Not tainted 5.3.0-rc3+ #160
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:trace_hardirqs_on+0x67/0x240 kernel/trace/trace_preemptirq.c:32
Code: 00 89 de e8 3b 85 fa ff 85 db 74 2d e8 b2 83 fa ff 65 c7 05 67 f7 8a 7e 00 00 00 00 e8 a2 83 fa ff 48 8b 7d 08 e8 29 fd e0 ff <48> 83 c4 08 5b 41 5c 41 5d 41 5e 41 5f 5d c3 e8 85 83 fa ff 48 8b
RSP: 0018:ffff8880a9a3fac8 EFLAGS: 00000046
RAX: 0000000000000007 RBX: 0000000000000000 RCX: 1ffffffff134b546
RDX: 0000000000000000 RSI: ffffffff817805ce RDI: ffffffff814598fa
RBP: ffff8880a9a3faf8 R08: ffff8880a9a2c580 R09: fffffbfff118c38a
R10: fffffbfff118c389 R11: ffffffff88c61c4b R12: ffffffff85d1c161
R13: ffffffff85d1c187 R14: ffffffff814598fa R15: dffffc0000000000
FS:  0000000000000000(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffff600400 CR3: 00000000a824f000 CR4: 00000000001406e0
Call Trace:
 __local_bh_enable_ip+0x15a/0x270 kernel/softirq.c:194
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 get_next_corpse net/netfilter/nf_conntrack_core.c:2014 [inline]
 nf_ct_iterate_cleanup+0x217/0x4e0 net/netfilter/nf_conntrack_core.c:2037
 nf_conntrack_cleanup_net_list+0x7a/0x240 net/netfilter/nf_conntrack_core.c:2224
 nf_conntrack_pernet_exit+0x159/0x1a0 net/netfilter/nf_conntrack_standalone.c:1151
 ops_exit_list.isra.0+0xfc/0x150 net/core/net_namespace.c:175
 cleanup_net+0x4e2/0xa60 net/core/net_namespace.c:594
 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