------------[ cut here ]------------
ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x90 arch/x86/include/asm/paravirt.h:768
WARNING: CPU: 1 PID: 8848 at lib/debugobjects.c:484 debug_print_object lib/debugobjects.c:481 [inline]
WARNING: CPU: 1 PID: 8848 at lib/debugobjects.c:484 __debug_check_no_obj_freed lib/debugobjects.c:963 [inline]
WARNING: CPU: 1 PID: 8848 at lib/debugobjects.c:484 debug_check_no_obj_freed+0x464/0x5b0 lib/debugobjects.c:994
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 8848 Comm: kworker/u4:2 Not tainted 5.3.0-rc1+ #50
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1d8/0x2f8 lib/dump_stack.c:113
 panic+0x29b/0x7d9 kernel/panic.c:219
 __warn+0x22f/0x230 kernel/panic.c:576
 report_bug+0x190/0x290 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 do_error_trap+0xd7/0x440 arch/x86/kernel/traps.c:272
 do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1026
RIP: 0010:debug_print_object lib/debugobjects.c:481 [inline]
RIP: 0010:__debug_check_no_obj_freed lib/debugobjects.c:963 [inline]
RIP: 0010:debug_check_no_obj_freed+0x464/0x5b0 lib/debugobjects.c:994
Code: 08 48 89 df e8 1d f7 49 fe 4c 8b 03 48 c7 c7 ba 56 88 88 48 c7 c6 9d f1 a0 88 4c 89 e2 44 89 f9 4d 89 e9 31 c0 e8 8c 62 e0 fd <0f> 0b 4c 8b 6d a8 ff 05 d4 87 95 05 49 83 c5 30 4c 89 e8 48 c1 e8
RSP: 0018:ffff888095a5f708 EFLAGS: 00010046
RAX: 80303b8c0ff75500 RBX: ffffffff88cd9fc0 RCX: ffff88808e1f2580
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000000
RBP: ffff888095a5f7a0 R08: ffffffff816063f4 R09: fffffbfff119a965
R10: fffffbfff119a965 R11: 0000000000000000 R12: ffffffff8893f14f
R13: ffffffff814f5ff0 R14: dffffc0000000000 R15: 0000000000000000
 kfree+0x107/0x200 mm/slab.c:3755
 kvfree+0x47/0x50 mm/util.c:488
 netdev_freemem+0x3e/0x60 net/core/dev.c:9088
 netdev_release+0x79/0xa0 net/core/net-sysfs.c:1635
 device_release+0x74/0x1a0 drivers/base/core.c:1060
 kobject_cleanup+0x2f7/0x4c0 lib/kobject.c:693
 kobject_release lib/kobject.c:722 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0xad/0xe0 lib/kobject.c:739
 netdev_run_todo+0xc6f/0xe20 net/core/dev.c:8993
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:112
 default_device_exit_batch+0x719/0x790 net/core/dev.c:9774
 ops_exit_list net/core/net_namespace.c:175 [inline]
 cleanup_net+0x77c/0xb30 net/core/net_namespace.c:594
 process_one_work+0x83b/0x1150 kernel/workqueue.c:2269
 worker_thread+0xc01/0x1630 kernel/workqueue.c:2415
 kthread+0x332/0x350 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..