============================= WARNING: suspicious RCU usage 4.17.0-rc1+ #16 Not tainted ----------------------------- net/ipv6/route.c:1550 suspicious rcu_dereference_protected() usage! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 3 locks held by udevd/2710: #0: 00000000907f75e3 (rcu_read_lock){....}, at: __d_lookup+0xb5/0x9c0 fs/dcache.c:2315 #1: 0000000033bb292c ((&n->timer)){+.-.}, at: lockdep_copy_map include/linux/lockdep.h:178 [inline] #1: 0000000033bb292c ((&n->timer)){+.-.}, at: call_timer_fn+0x1bb/0x940 kernel/time/timer.c:1316 #2: 00000000907f75e3 (rcu_read_lock){....}, at: ip6_link_failure+0xfe/0x790 net/ipv6/route.c:2227 stack backtrace: CPU: 1 PID: 2710 Comm: udevd Not tainted 4.17.0-rc1+ #16 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+0x1b9/0x294 lib/dump_stack.c:113 lockdep_rcu_suspicious+0x14a/0x153 kernel/locking/lockdep.c:4592 rt6_remove_exception_rt+0x416/0x4d0 net/ipv6/route.c:1549 ip6_link_failure+0x484/0x790 net/ipv6/route.c:2231 dst_link_failure include/net/dst.h:427 [inline] ndisc_error_report+0xd1/0x1c0 net/ipv6/ndisc.c:695 neigh_invalidate+0x246/0x550 net/core/neighbour.c:891 neigh_timer_handler+0xaf9/0xde0 net/core/neighbour.c:977 call_timer_fn+0x230/0x940 kernel/time/timer.c:1326 expire_timers kernel/time/timer.c:1363 [inline] __run_timers+0x79e/0xc50 kernel/time/timer.c:1666 run_timer_softirq+0x4c/0x70 kernel/time/timer.c:1692 __do_softirq+0x2e0/0xaf5 kernel/softirq.c:285 invoke_softirq kernel/softirq.c:365 [inline] irq_exit+0x1d1/0x200 kernel/softirq.c:405 exiting_irq arch/x86/include/asm/apic.h:525 [inline] smp_apic_timer_interrupt+0x17e/0x710 arch/x86/kernel/apic/apic.c:1052 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:863 RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline] RIP: 0010:hlist_bl_first_rcu include/linux/rculist_bl.h:24 [inline] RIP: 0010:__d_lookup+0x156/0x9c0 fs/dcache.c:2343 RSP: 0018:ffff8801b5d17548 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: dffffc0000000000 RBX: ffffc900004943e0 RCX: ffffffff81c7646b RDX: 1ffff9200009287c RSI: ffffffff81c75ee1 RDI: 0000000000000001 RBP: ffff8801b5d176b0 R08: ffff8801b5d04400 R09: ffffed003b5e46c2 R10: ffffed003b5e46c2 R11: ffff8801daf23613 R12: 0000000000000001 R13: ffff8801b5d17978 R14: ffff8801b5d17688 R15: ffff8801b5d17b80 lookup_fast+0x4ad/0x1290 fs/namei.c:1576 walk_component+0x130/0x2550 fs/namei.c:1765 lookup_last fs/namei.c:2237 [inline] path_lookupat.isra.44+0x1f6/0xbd0 fs/namei.c:2287 filename_lookup+0x258/0x4f0 fs/namei.c:2321 user_path_at_empty+0x40/0x50 fs/namei.c:2555 do_readlinkat+0x143/0x3e0 fs/stat.c:394 __do_sys_readlink fs/stat.c:427 [inline] __se_sys_readlink fs/stat.c:424 [inline] __x64_sys_readlink+0x78/0xb0 fs/stat.c:424 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x7f9ee28ee577 RSP: 002b:00007ffe3f7e4138 EFLAGS: 00000246 ORIG_RAX: 0000000000000059 RAX: ffffffffffffffda RBX: 0000000000d23250 RCX: 00007f9ee28ee577 RDX: 0000000000000400 RSI: 00007ffe3f7e4140 RDI: 00007ffe3f7e4620 RBP: 00007ffe3f7e4e60 R08: 00007ffe3f7e4e60 R09: 00007f9ee29431a0 R10: 7665642f7379732f R11: 0000000000000246 R12: 00007ffe3f7e4620 R13: 0000000000000400 R14: 0000000000d23250 R15: 0000000000d28e10 IPVS: set_ctl: invalid protocol: 0 224.0.0.1:20003 lc IPVS: set_ctl: invalid protocol: 0 224.0.0.1:20003 lc