===================================== WARNING: bad unlock balance detected! 4.16.0-rc2+ #323 Not tainted ------------------------------------- sshd/4161 is trying to release lock (rcu_read_lock_bh) at: [] rcu_read_unlock_bh include/linux/rcupdate.h:722 [inline] [] hashlimit_mt_common.isra.10+0x1beb/0x2610 net/netfilter/xt_hashlimit.c:777 but there are no more locks to release! other info that might help us debug this: 3 locks held by sshd/4161: #0: ((&ndev->rs_timer)){+.-.}, at: [<000000008de40325>] lockdep_copy_map include/linux/lockdep.h:178 [inline] #0: ((&ndev->rs_timer)){+.-.}, at: [<000000008de40325>] call_timer_fn+0x1c6/0x820 kernel/time/timer.c:1316 #1: (rcu_read_lock){....}, at: [<00000000a2c45d58>] ip6_nd_hdr net/ipv6/ndisc.c:449 [inline] #1: (rcu_read_lock){....}, at: [<00000000a2c45d58>] ndisc_send_skb+0x826/0x1370 net/ipv6/ndisc.c:485 #2: (rcu_read_lock){....}, at: [<00000000c2d8d42e>] nf_hook.constprop.27+0x0/0x830 net/ipv6/ndisc.c:387 stack backtrace: CPU: 1 PID: 4161 Comm: sshd Not tainted 4.16.0-rc2+ #323 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 print_unlock_imbalance_bug+0x12f/0x140 kernel/locking/lockdep.c:3484 __lock_release kernel/locking/lockdep.c:3691 [inline] lock_release+0x6fe/0xa40 kernel/locking/lockdep.c:3939 rcu_lock_release include/linux/rcupdate.h:249 [inline] rcu_read_unlock_bh include/linux/rcupdate.h:724 [inline] hashlimit_mt_common.isra.10+0x1c08/0x2610 net/netfilter/xt_hashlimit.c:777 hashlimit_mt+0x78/0x90 net/netfilter/xt_hashlimit.c:846 ip6t_do_table+0x98d/0x1a30 net/ipv6/netfilter/ip6_tables.c:319 ip6table_raw_hook+0x65/0x80 net/ipv6/netfilter/ip6table_raw.c:42 nf_hook_entry_hookfn include/linux/netfilter.h:120 [inline] nf_hook_slow+0xba/0x1a0 net/netfilter/core.c:483 nf_hook.constprop.27+0x3f6/0x830 include/linux/netfilter.h:243 NF_HOOK include/linux/netfilter.h:286 [inline] ndisc_send_skb+0xa51/0x1370 net/ipv6/ndisc.c:491 ndisc_send_rs+0x126/0x670 net/ipv6/ndisc.c:685 addrconf_rs_timer+0x363/0x6b0 net/ipv6/addrconf.c:3769 call_timer_fn+0x228/0x820 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x7ee/0xb70 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2d7/0xb85 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1cc/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:541 [inline] smp_apic_timer_interrupt+0x16b/0x700 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0x8e/0xa0 arch/x86/entry/entry_64.S:796 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:777 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0x5e/0xba kernel/locking/spinlock.c:184 RSP: 0018:ffff8801b18a7288 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff12 RAX: dffffc0000000000 RBX: 0000000000000282 RCX: 0000000000000000 RDX: 1ffffffff0d592d5 RSI: 0000000000000001 RDI: 0000000000000282 RBP: ffff8801b18a7298 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801db525d40 R13: dffffc0000000000 R14: ffff8801db525dc0 R15: ffff8801db525dc0 unlock_hrtimer_base kernel/time/hrtimer.c:871 [inline] hrtimer_start_range_ns+0x57e/0xb80 kernel/time/hrtimer.c:1102 hrtimer_start_expires include/linux/hrtimer.h:412 [inline] schedule_hrtimeout_range_clock+0x1d6/0x460 kernel/time/hrtimer.c:1892 schedule_hrtimeout_range+0x2a/0x40 kernel/time/hrtimer.c:1940 poll_schedule_timeout+0x10f/0x1f0 fs/select.c:243 do_select+0x11de/0x1700 fs/select.c:581 core_sys_select+0x480/0x960 fs/select.c:655 SYSC_select fs/select.c:696 [inline] SyS_select+0x194/0x230 fs/select.c:678 do_syscall_64+0x280/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x42/0xb7 RIP: 0033:0x7fdabc377dd3 RSP: 002b:00007fff8fd115a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000017 RAX: ffffffffffffffda RBX: 00007fff8fd11630 RCX: 00007fdabc377dd3 RDX: 000055c05aed0ae0 RSI: 000055c05aed0b00 RDI: 000000000000000c RBP: 000055c05928a8dc R08: 00007fff8fd115d0 R09: 0101010101010101 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff8fd11638 R13: 0000000000000000 R14: 00007fff8fd11628 R15: 00007fff8fd1162c