======================================
| [ 29.419637][ T11] #1: ffffc900000b7d40 ((work_completion)(&port->wq)){+.+.}-{0:0}, at: process_one_work (kernel/workqueue.c:3214) 
| [ 29.419949][ T11] #2: ffffffff9675b5c0 (rcu_read_lock_bh){....}-{1:3}, at: __dev_queue_xmit (./include/linux/bottom_half.h:20 ./include/linux/rcupdate.h:901 net/core/dev.c:4555) 
| [   29.420236][   T11]
| [   29.420236][   T11] stack backtrace:
[   29.420429][   T11] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
[   29.420431][   T11] Workqueue: events ipvlan_process_multicast
[   29.420438][   T11] Call Trace:
[   29.420440][   T11]  <TASK>
[ 29.420443][ T11] dump_stack_lvl (lib/dump_stack.c:123) 
[ 29.420450][ T11] lockdep_rcu_suspicious (kernel/locking/lockdep.c:6848) 
[ 29.420461][ T11] dev_hard_start_xmit (./include/net/net_namespace.h:418 ./include/linux/netdevice.h:2695 net/core/dev.c:2466 net/core/dev.c:3772 net/core/dev.c:3793) 
[ 29.420472][ T11] __dev_queue_xmit (net/core/dev.h:340 net/core/dev.c:4631) 
[ 29.420488][ T11] ? __pfx___dev_queue_xmit (net/core/dev.c:4538) 
[ 29.420491][ T11] ? find_held_lock (kernel/locking/lockdep.c:5341) 
[ 29.420499][ T11] ? __lock_release (kernel/locking/lockdep.c:5527) 
[ 29.420501][ T11] ? ipvlan_process_multicast (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 drivers/net/ipvlan/ipvlan_core.c:284) 
[ 29.420506][ T11] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 29.420509][ T11] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5816) 
[ 29.420522][ T11] ? ipvlan_process_multicast (./include/linux/rcupdate.h:347 ./include/linux/rcupdate.h:880 drivers/net/ipvlan/ipvlan_core.c:284) 
[ 29.420530][ T11] ipvlan_process_multicast (./include/linux/netdevice.h:3331 drivers/net/ipvlan/ipvlan_core.c:290) 
[ 29.420547][ T11] ? __pfx_ipvlan_process_multicast (drivers/net/ipvlan/ipvlan_core.c:229) 
[ 29.420553][ T11] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 29.420557][ T11] ? __pfx_lock_acquire.part.0 (kernel/locking/lockdep.c:5816) 
[ 29.420561][ T11] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 21)) 
[ 29.420564][ T11] ? trace_lock_acquire (./include/trace/events/lock.h:24 (discriminator 21)) 
[ 29.420572][ T11] ? lock_acquire (kernel/locking/lockdep.c:5824) 
[ 29.420580][ T11] ? process_one_work (kernel/workqueue.c:3238) 
[ 29.420583][ T11] ? process_one_work (kernel/workqueue.c:3214) 
[ 29.420586][ T11] process_one_work (kernel/workqueue.c:3238) 
[ 29.420599][ T11] ? __pfx___lock_release (kernel/locking/lockdep.c:5503) 
[ 29.420604][ T11] ? __pfx_process_one_work (kernel/workqueue.c:3140) 
[ 29.420617][ T11] ? assign_work (kernel/workqueue.c:1200) 
[ 29.420626][ T11] worker_thread (kernel/workqueue.c:3313 kernel/workqueue.c:3400) 
[ 29.420631][ T11] ? lockdep_hardirqs_on_prepare (kernel/locking/lockdep.c:4349 kernel/locking/lockdep.c:4408) 
[ 29.420641][ T11] ? __pfx_worker_thread (kernel/workqueue.c:3346) 
[ 29.420648][ T11] kthread (kernel/kthread.c:464) 
[ 29.420654][ T11] ? __pfx_kthread (kernel/kthread.c:413) 
[ 29.420663][ T11] ? __pfx_kthread (kernel/kthread.c:413) 
[ 29.420669][ T11] ret_from_fork (arch/x86/kernel/process.c:148) 
[ 29.420673][ T11] ? __pfx_kthread (kernel/kthread.c:413) 


Finger prints:
lockdep_rcu_suspicious:dev_hard_start_xmit:__dev_queue_xmit:ipvlan_process_multicast:process_one_work