pktgen: kernel_thread() failed for cpu 0
pktgen: Cannot create thread for cpu 0 (-4)
pktgen: kernel_thread() failed for cpu 1
pktgen: Cannot create thread for cpu 1 (-4)
pktgen: Initialization failed for all threads
BUG: sleeping function called from invalid context at kernel/sched/completion.c:90
in_atomic(): 1, irqs_disabled(): 0, pid: 17, name: ksoftirqd/1
1 lock held by ksoftirqd/1/17:
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] __rcu_reclaim kernel/rcu/rcu.h:108 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] rcu_process_callbacks+0x98e/0x12b0 kernel/rcu/tree.c:3037
Preemption disabled at:
[<ffffffff83a0884d>] __do_softirq+0xdd/0x940 kernel/softirq.c:265
CPU: 1 PID: 17 Comm: ksoftirqd/1 Not tainted 4.9.123-g7fa8c15 #80
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
 ffff8801d9abf868 ffffffff81eb9689 ffffffff83a0884d 0000000000000000
 0000000000000100 ffff8801d9aa3000 ffff8801d9aa3000 ffff8801d9abf8a0
 ffffffff81426911 ffff8801d9aa3000 ffffffff83c5a3c0 000000000000005a
Call Trace:
 [<ffffffff81eb9689>] __dump_stack lib/dump_stack.c:15 [inline]
 [<ffffffff81eb9689>] dump_stack+0xc1/0x128 lib/dump_stack.c:51
 [<ffffffff81426911>] ___might_sleep.cold.123+0x1bc/0x1f5 kernel/sched/core.c:7988
 [<ffffffff811bd9a5>] __might_sleep+0x95/0x1a0 kernel/sched/core.c:7945
 [<ffffffff839f5509>] __wait_for_common kernel/sched/completion.c:90 [inline]
 [<ffffffff839f5509>] wait_for_common kernel/sched/completion.c:101 [inline]
 [<ffffffff839f5509>] wait_for_completion+0x89/0x2e0 kernel/sched/completion.c:122
 [<ffffffff8127e117>] __wait_rcu_gp+0x137/0x1b0 kernel/rcu/update.c:369
 [<ffffffff812863aa>] synchronize_rcu.part.62+0xfa/0x110 kernel/rcu/tree_plugin.h:684
 [<ffffffff812863e7>] synchronize_rcu+0x27/0x90 kernel/rcu/tree_plugin.h:685
 [<ffffffff836c4f2a>] __l2tp_session_unhash+0x38a/0x520 net/l2tp/l2tp_core.c:1796
 [<ffffffff836c52b7>] l2tp_tunnel_closeall+0x1f7/0x350 net/l2tp/l2tp_core.c:1364
 [<ffffffff836c5b72>] l2tp_tunnel_destruct+0x2f2/0x590 net/l2tp/l2tp_core.c:1324
 [<ffffffff830281f5>] __sk_destruct+0x55/0x590 net/core/sock.c:1428
 [<ffffffff81289aae>] __rcu_reclaim kernel/rcu/rcu.h:118 [inline]
 [<ffffffff81289aae>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 [<ffffffff81289aae>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 [<ffffffff81289aae>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 [<ffffffff81289aae>] rcu_process_callbacks+0x8ae/0x12b0 kernel/rcu/tree.c:3037
 [<ffffffff83a08980>] __do_softirq+0x210/0x940 kernel/softirq.c:288
 [<ffffffff8114d320>] run_ksoftirqd+0x30/0x60 kernel/softirq.c:680
 [<ffffffff811aa5a9>] smpboot_thread_fn+0x5c9/0x900 kernel/smpboot.c:163
 [<ffffffff8119f3cd>] kthread+0x26d/0x300 kernel/kthread.c:211
 [<ffffffff83a01f5c>] ret_from_fork+0x5c/0x70 arch/x86/entry/entry_64.S:373
BUG: scheduling while atomic: ksoftirqd/1/17/0x00000101
1 lock held by ksoftirqd/1/17:
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] __rcu_reclaim kernel/rcu/rcu.h:108 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] rcu_do_batch kernel/rcu/tree.c:2789 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] invoke_rcu_callbacks kernel/rcu/tree.c:3053 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] __rcu_process_callbacks kernel/rcu/tree.c:3020 [inline]
 #0:  (rcu_callback){......}, at: [<ffffffff81289b8e>] rcu_process_callbacks+0x98e/0x12b0 kernel/rcu/tree.c:3037
Modules linked in:
Preemption disabled at:
[<ffffffff83a0884d>] __do_softirq+0xdd/0x940 kernel/softirq.c:265