------------[ 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:752
WARNING: CPU: 0 PID: 9996 at lib/debugobjects.c:485 debug_print_object+0x168/0x250 lib/debugobjects.c:485
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 9996 Comm: kworker/u4:0 Not tainted 5.6.0-rc3-syzkaller #0
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+0x197/0x210 lib/dump_stack.c:118
 panic+0x2e3/0x75c kernel/panic.c:221
 __warn.cold+0x2f/0x3e kernel/panic.c:582
 report_bug+0x289/0x300 lib/bug.c:195
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 fixup_bug arch/x86/kernel/traps.c:169 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:267
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:286
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:debug_print_object+0x168/0x250 lib/debugobjects.c:485
Code: dd c0 e5 91 88 48 89 fa 48 c1 ea 03 80 3c 02 00 0f 85 b5 00 00 00 48 8b 14 dd c0 e5 91 88 48 c7 c7 20 db 91 88 e8 a7 6e 9f fd <0f> 0b 83 05 a3 7b ff 06 01 48 83 c4 20 5b 41 5c 41 5d 41 5e 5d c3
RSP: 0018:ffffc9000650f840 EFLAGS: 00010082
RAX: 0000000000000000 RBX: 0000000000000003 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815eae46 RDI: fffff52000ca1efa
RBP: ffffc9000650f880 R08: ffff888047bf8500 R09: ffffed1015d045c9
R10: ffffed1015d045c8 R11: ffff8880ae822e43 R12: 0000000000000001
R13: ffffffff89bb6940 R14: ffffffff816487c0 R15: ffff8880a7fce118
 __debug_check_no_obj_freed lib/debugobjects.c:967 [inline]
 debug_check_no_obj_freed+0x2d6/0x441 lib/debugobjects.c:998
 kfree+0xf8/0x2c0 mm/slab.c:3756
 kvfree+0x4a/0x60 mm/util.c:603
 netdev_freemem+0x4c/0x60 net/core/dev.c:9739
 netdev_release+0x86/0xb0 net/core/net-sysfs.c:1644
 device_release+0x7a/0x210 drivers/base/core.c:1358
 kobject_cleanup lib/kobject.c:693 [inline]
 kobject_release lib/kobject.c:722 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x1ff/0x2e0 lib/kobject.c:739
 netdev_run_todo+0x535/0x7d0 net/core/dev.c:9644
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:112
 default_device_exit_batch+0x36a/0x420 net/core/dev.c:10441
 ops_exit_list.isra.0+0x10c/0x160 net/core/net_namespace.c:175
 cleanup_net+0x549/0xb10 net/core/net_namespace.c:589
 process_one_work+0xa05/0x17a0 kernel/workqueue.c:2264
 worker_thread+0x98/0xe40 kernel/workqueue.c:2410
 kthread+0x361/0x430 kernel/kthread.c:255
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352
Kernel Offset: disabled
Rebooting in 86400 seconds..