INFO: rcu_preempt self-detected stall on CPU
	1-...: (1 GPs behind) idle=d9e/140000000000002/0 softirq=40728/40730 fqs=7 
	 (t=10500 jiffies g=10591 c=10590 q=1348)
rcu_preempt kthread starved for 10446 jiffies! g10591 c10590 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
rcu_preempt     R  running task    29920     8      2 0x80000000
Call Trace:
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_timeout+0x43c/0xe40 kernel/time/timer.c:1746
 rcu_gp_kthread+0xb8e/0x1ce0 kernel/rcu/tree.c:2255
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404
NMI backtrace for cpu 1
CPU: 1 PID: 18225 Comm: syz-executor.0 Not tainted 4.14.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x13e/0x194 lib/dump_stack.c:58
 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x139/0x17e lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:158 [inline]
 rcu_dump_cpu_stacks+0x16d/0x1b8 kernel/rcu/tree.c:1396
 print_cpu_stall kernel/rcu/tree.c:1542 [inline]
 check_cpu_stall kernel/rcu/tree.c:1610 [inline]
 __rcu_pending kernel/rcu/tree.c:3390 [inline]
 rcu_pending kernel/rcu/tree.c:3452 [inline]
 rcu_check_callbacks.cold+0x490/0xdaa kernel/rcu/tree.c:2792
 update_process_times+0x29/0x60 kernel/time/timer.c:1590
 tick_sched_handle+0x7d/0x150 kernel/time/tick-sched.c:165
 tick_sched_timer+0x3e/0x120 kernel/time/tick-sched.c:1223
 __run_hrtimer kernel/time/hrtimer.c:1223 [inline]
 __hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287
 hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
 smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100
 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
RIP: 0010:loopback_xmit+0x0/0x576 drivers/net/loopback.c:73
RSP: 0018:ffff8880aeb07368 EFLAGS: 00010246 ORIG_RAX: ffffffffffffff10
RAX: 1ffffffff0e14180 RBX: ffff8880575fc580 RCX: 0000000000000000
RDX: 0000000000000006 RSI: ffff888094abc1c0 RDI: ffff8880575fc580
RBP: dffffc0000000000 R08: ffffffff84ff1282 R09: 0000000000022297
R10: ffff88820cd1e9e8 R11: ffff88820cd1e0c0 R12: 00000000d7f14000
R13: ffff888094abc1c0 R14: ffff88809064e300 R15: ffffffff870a0be0
 __netdev_start_xmit include/linux/netdevice.h:4039 [inline]
 netdev_start_xmit include/linux/netdevice.h:4048 [inline]
 xmit_one net/core/dev.c:3009 [inline]
 dev_hard_start_xmit+0x186/0x890 net/core/dev.c:3025
 __dev_queue_xmit+0x1d91/0x25c0 net/core/dev.c:3525
 neigh_hh_output include/net/neighbour.h:490 [inline]
 neigh_output include/net/neighbour.h:498 [inline]
 ip_finish_output2+0xde8/0x14a0 net/ipv4/ip_output.c:229
 ip_finish_output+0x556/0xc30 net/ipv4/ip_output.c:317
 NF_HOOK_COND include/linux/netfilter.h:239 [inline]
 ip_output+0x1c2/0x520 net/ipv4/ip_output.c:405
 dst_output include/net/dst.h:462 [inline]
 ip_local_out+0x93/0x170 net/ipv4/ip_output.c:124
 ip_queue_xmit+0x7b2/0x1b20 net/ipv4/ip_output.c:504
 sctp_packet_transmit+0x17f7/0x2d70 net/sctp/output.c:637
 sctp_outq_flush+0xc54/0x2dd0 net/sctp/outqueue.c:1187
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1787 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1179 [inline]
 sctp_do_sm+0x419/0x4a90 net/sctp/sm_sideeffect.c:1150
 sctp_generate_heartbeat_event+0x1da/0x3f0 net/sctp/sm_sideeffect.c:391
 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279
 expire_timers kernel/time/timer.c:1318 [inline]
 __run_timers kernel/time/timer.c:1636 [inline]
 __run_timers kernel/time/timer.c:1604 [inline]
 run_timer_softirq+0x52a/0x1390 kernel/time/timer.c:1649
 __do_softirq+0x254/0x9bf kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x15b/0x1a0 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:648 [inline]
 smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102
 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
 </IRQ>
RIP: 0010:lock_is_held include/linux/lockdep.h:437 [inline]
RIP: 0010:schedule_debug kernel/sched/core.c:3206 [inline]
RIP: 0010:__schedule+0xdd0/0x1ca0 kernel/sched/core.c:3308
RSP: 0018:ffff888201a7fcb8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000001 RBX: ffff888201a78000 RCX: 1ffffffff10279b4
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff88820cd1e944
RBP: ffff888201a7fd60 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: 000000000002b540 R14: ffff88820cd1e0c0 R15: ffff8880aeb2b540
 preempt_schedule_common+0x4a/0xc0 kernel/sched/core.c:3508
 ___preempt_schedule+0x16/0x18
 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock+0x3b/0x40 kernel/locking/spinlock.c:184
 spin_unlock include/linux/spinlock.h:357 [inline]
 setfl fs/fcntl.c:81 [inline]
 do_fcntl+0x95d/0xde0 fs/fcntl.c:347
 SYSC_fcntl fs/fcntl.c:463 [inline]
 SyS_fcntl+0xc6/0x100 fs/fcntl.c:448
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c829
RSP: 002b:00007f34889bbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000048
RAX: ffffffffffffffda RBX: 00000000004dbd00 RCX: 000000000045c829
RDX: 0000000000002000 RSI: 0000000000000004 RDI: 0000000000000008
RBP: 000000000078c0e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000c7 R14: 00000000004c353a R15: 00007f34889bc6d4
INFO: rcu_sched detected stalls on CPUs/tasks:
	1-...: (1 GPs behind) idle=d9e/140000000000001/0 softirq=40729/40730 fqs=7 
	(detected by 0, t=10566 jiffies, g=4916, c=4915, q=1)
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 18225 Comm: syz-executor.0 Not tainted 4.14.177-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff88820cd1e0c0 task.stack: ffff888201a78000
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline]
RIP: 0010:lock_release+0x418/0x7f0 kernel/locking/lockdep.c:4020
RSP: 0018:ffff8880aeb06f68 EFLAGS: 00000086
RAX: 1ffffffff0fa2cd1 RBX: 1ffff11015d60df1 RCX: 1ffff110419a3d27
RDX: dffffc0000000000 RSI: 0000000000000004 RDI: ffff88820cd1e944
RBP: ffff88820cd1e0c0 R08: 0000000000000001 R09: 0000000000000003
R10: ffff88820cd1e9c0 R11: ffff88820cd1e0c0 R12: ffffffff816b2ad2
R13: 0000000000000003 R14: ffff88820cd1e0c0 R15: 0000000000000004
FS:  00007f34889bc700(0000) GS:ffff8880aeb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f348899adb8 CR3: 0000000057696000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 rcu_lock_release include/linux/rcupdate.h:247 [inline]
 rcu_read_unlock include/linux/rcupdate.h:685 [inline]
 __perf_output_begin kernel/events/ring_buffer.c:254 [inline]
 perf_output_begin_forward+0x6b9/0xa20 kernel/events/ring_buffer.c:262
 __perf_event_output kernel/events/core.c:6272 [inline]
 perf_event_output_forward+0xde/0x1f0 kernel/events/core.c:6288
 __perf_event_overflow+0x113/0x310 kernel/events/core.c:7526
 perf_swevent_hrtimer+0x220/0x350 kernel/events/core.c:8736
 __run_hrtimer kernel/time/hrtimer.c:1223 [inline]
 __hrtimer_run_queues+0x25c/0xbb0 kernel/time/hrtimer.c:1287
 hrtimer_interrupt+0x1e6/0x5e0 kernel/time/hrtimer.c:1321
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1075 [inline]
 smp_apic_timer_interrupt+0x117/0x5e0 arch/x86/kernel/apic/apic.c:1100
 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
RIP: 0010:sctp_assoc_lookup_paddr+0x5a/0xc0 net/sctp/associola.c:774
RSP: 0018:ffff8880aeb078e0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 1ffff11012295000 RBX: ffff88805f52d844 RCX: ffff88805f52d788
RDX: 0000000000000100 RSI: ffff8880914a8088 RDI: 0000000000000000
RBP: ffff8880971aab50 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8880914a8000
R13: dffffc0000000000 R14: ffff8880971ab170 R15: ffff8880971aaa00
 sctp_outq_flush+0x9f1/0x2dd0 net/sctp/outqueue.c:839
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1308 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1179 [inline]
 sctp_do_sm+0x372c/0x4a90 net/sctp/sm_sideeffect.c:1150
 sctp_generate_heartbeat_event+0x1da/0x3f0 net/sctp/sm_sideeffect.c:391
 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279
 expire_timers kernel/time/timer.c:1318 [inline]
 __run_timers kernel/time/timer.c:1636 [inline]
 __run_timers kernel/time/timer.c:1604 [inline]
 run_timer_softirq+0x52a/0x1390 kernel/time/timer.c:1649
 __do_softirq+0x254/0x9bf kernel/softirq.c:288
 invoke_softirq kernel/softirq.c:368 [inline]
 irq_exit+0x15b/0x1a0 kernel/softirq.c:409
 exiting_irq arch/x86/include/asm/apic.h:648 [inline]
 smp_apic_timer_interrupt+0x141/0x5e0 arch/x86/kernel/apic/apic.c:1102
 apic_timer_interrupt+0x8f/0xa0 arch/x86/entry/entry_64.S:792
 </IRQ>
RIP: 0010:lock_is_held include/linux/lockdep.h:437 [inline]
RIP: 0010:schedule_debug kernel/sched/core.c:3206 [inline]
RIP: 0010:__schedule+0xdd0/0x1ca0 kernel/sched/core.c:3308
RSP: 0018:ffff888201a7fcb8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff10
RAX: 0000000000000001 RBX: ffff888201a78000 RCX: 1ffffffff10279b4
RDX: 0000000000000000 RSI: 00000000ffffffff RDI: ffff88820cd1e944
RBP: ffff888201a7fd60 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001
R13: 000000000002b540 R14: ffff88820cd1e0c0 R15: ffff8880aeb2b540
 preempt_schedule_common+0x4a/0xc0 kernel/sched/core.c:3508
 ___preempt_schedule+0x16/0x18
 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline]
 _raw_spin_unlock+0x3b/0x40 kernel/locking/spinlock.c:184
 spin_unlock include/linux/spinlock.h:357 [inline]
 setfl fs/fcntl.c:81 [inline]
 do_fcntl+0x95d/0xde0 fs/fcntl.c:347
 SYSC_fcntl fs/fcntl.c:463 [inline]
 SyS_fcntl+0xc6/0x100 fs/fcntl.c:448
 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x45c829
RSP: 002b:00007f34889bbc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000048
RAX: ffffffffffffffda RBX: 00000000004dbd00 RCX: 000000000045c829
RDX: 0000000000002000 RSI: 0000000000000004 RDI: 0000000000000008
RBP: 000000000078c0e0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000000c7 R14: 00000000004c353a R15: 00007f34889bc6d4
Code: 00 00 fc ff df c7 85 84 08 00 00 00 00 00 00 48 c1 e8 03 80 3c 10 00 0f 85 d9 02 00 00 48 83 3d 46 32 8b 06 00 0f 84 ba 01 00 00 <48> 8b 3c 24 57 9d 0f 1f 44 00 00 48 b8 00 00 00 00 00 fc ff df 
rcu_sched kthread starved for 10513 jiffies! g4916 c4915 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=0
rcu_sched       R  running task    29984     9      2 0x80000000
Call Trace:
 schedule+0x8d/0x1b0 kernel/sched/core.c:3428
 schedule_timeout+0x43c/0xe40 kernel/time/timer.c:1746
 rcu_gp_kthread+0xb8e/0x1ce0 kernel/rcu/tree.c:2255
 kthread+0x30d/0x420 kernel/kthread.c:232
 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:404