kernel msg: ebtables bug: please report to author: Hook order must be followed rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (9186 ticks this GP) idle=bba/1/0x4000000000000002 softirq=15870/15870 fqs=2 rcu: (t=10500 jiffies g=19285 q=622) rcu: rcu_preempt kthread starved for 4258 jiffies! g19285 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt I23064 10 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2825 [inline] __schedule+0x86c/0x1ed0 kernel/sched/core.c:3473 schedule+0xfe/0x460 kernel/sched/core.c:3517 schedule_timeout+0x140/0x260 kernel/time/timer.c:1804 rcu_gp_kthread+0x9d9/0x2310 kernel/rcu/tree.c:2194 kthread+0x35a/0x420 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413 NMI backtrace for cpu 1 CPU: 1 PID: 11616 Comm: syz-executor4 Not tainted 4.19.0-rc7+ #280 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1c4/0x2b4 lib/dump_stack.c:113 nmi_cpu_backtrace.cold.3+0x63/0xa2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x1b3/0x1ed lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:162 [inline] rcu_dump_cpu_stacks+0x175/0x1c2 kernel/rcu/tree.c:1340 print_cpu_stall.cold.78+0x2d3/0x524 kernel/rcu/tree.c:1478 check_cpu_stall kernel/rcu/tree.c:1550 [inline] __rcu_pending kernel/rcu/tree.c:3276 [inline] rcu_pending kernel/rcu/tree.c:3319 [inline] rcu_check_callbacks+0xfd9/0x1990 kernel/rcu/tree.c:2665 update_process_times+0x2d/0x70 kernel/time/timer.c:1636 tick_sched_handle+0x9f/0x180 kernel/time/tick-sched.c:164 tick_sched_timer+0x45/0x130 kernel/time/tick-sched.c:1274 __run_hrtimer kernel/time/hrtimer.c:1398 [inline] __hrtimer_run_queues+0x41c/0x10d0 kernel/time/hrtimer.c:1460 hrtimer_interrupt+0x313/0x780 kernel/time/hrtimer.c:1518 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1029 [inline] smp_apic_timer_interrupt+0x1a1/0x760 arch/x86/kernel/apic/apic.c:1054 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:864 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:788 [inline] RIP: 0010:kfree+0x11a/0x230 mm/slab.c:3814 Code: 1f 44 00 00 e8 a7 c9 c2 ff 5b 41 5c 41 5d 41 5e 5d c3 e8 89 c6 c2 ff 48 83 3d 49 d4 6f 07 00 0f 84 0a 01 00 00 4c 89 e7 57 9d <0f> 1f 44 00 00 5b 41 5c 41 5d 41 5e 5d c3 4c 89 f2 48 89 de 4c 89 RSP: 0018:ffff8801b9f47858 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000000 RBX: ffff88018447a580 RCX: 1ffff100308279b4 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000286 RBP: ffff8801b9f47878 R08: ffff88018413cda0 R09: 0000000000000007 R10: 0000000000000000 R11: ffff88018413c500 R12: 0000000000000286 R13: ffff8801da8007c0 R14: ffffffff81dd63fb R15: 0000000000000000 iter_file_splice_write+0x7ab/0x1050 fs/splice.c:777 do_splice_from fs/splice.c:852 [inline] direct_splice_actor+0x128/0x190 fs/splice.c:1019 splice_direct_to_actor+0x318/0x8f0 fs/splice.c:974 do_splice_direct+0x2d4/0x420 fs/splice.c:1062 do_sendfile+0x62a/0xe20 fs/read_write.c:1440 __do_sys_sendfile64 fs/read_write.c:1495 [inline] __se_sys_sendfile64 fs/read_write.c:1487 [inline] __x64_sys_sendfile64+0x15d/0x250 fs/read_write.c:1487 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x457569 Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fb98ce41c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000000457569 RDX: 00000000200001c0 RSI: 0000000000000005 RDI: 0000000000000005 RBP: 000000000072bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 7fffffffffffffff R11: 0000000000000246 R12: 00007fb98ce426d4 R13: 00000000004c34d0 R14: 00000000004d5298 R15: 00000000ffffffff