INFO: rcu_preempt self-detected stall on CPU 0-...: (1 GPs behind) idle=152/140000000000002/0 softirq=54295/54296 fqs=3 (t=10500 jiffies g=15436 c=15435 q=183) rcu_preempt kthread starved for 6277 jiffies! g15436 c15435 f0x0 RCU_GP_WAIT_FQS(3) ->state=0x0 ->cpu=1 rcu_preempt R running task 29904 8 2 0x80000000 Call Trace: context_switch kernel/sched/core.c:2808 [inline] __schedule+0x8a6/0x1d70 kernel/sched/core.c:3384 schedule+0x8d/0x1b0 kernel/sched/core.c:3428 schedule_timeout+0x4df/0xe50 kernel/time/timer.c:1746 rcu_gp_kthread+0xb3d/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 0 CPU: 0 PID: 26067 Comm: syz-executor.0 Not tainted 4.14.184-syzkaller #0 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+0x1b2/0x283 lib/dump_stack.c:58 nmi_cpu_backtrace.cold+0x57/0x93 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x13a/0x17f 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.isra.0+0x73/0x150 kernel/time/tick-sched.c:165 tick_sched_timer+0x41/0x120 kernel/time/tick-sched.c:1223 __run_hrtimer kernel/time/hrtimer.c:1223 [inline] __hrtimer_run_queues+0x24b/0xb90 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+0x117/0x5f0 arch/x86/kernel/apic/apic.c:1100 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:192 RSP: 0018:ffff8880aec074b0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0f62cd1 RBX: 0000000000000282 RCX: 1ffff11012a8ed15 RDX: dffffc0000000000 RSI: ffff888095476900 RDI: 0000000000000282 RBP: ffffffff8a4b1348 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000056300 R13: ffff8880a64d5930 R14: 0000000000000000 R15: ffffffff8a4b1348 __debug_object_init+0x167/0x7a0 lib/debugobjects.c:380 debug_object_init lib/debugobjects.c:393 [inline] debug_object_activate+0x274/0x450 lib/debugobjects.c:474 debug_rcu_head_queue kernel/rcu/rcu.h:152 [inline] __call_rcu.constprop.0+0x31/0x7e0 kernel/rcu/tree.c:3050 dst_release+0x56/0x80 net/core/dst.c:188 refdst_drop include/net/dst.h:286 [inline] skb_dst_drop include/net/dst.h:298 [inline] __dev_queue_xmit+0x16ed/0x25a0 net/core/dev.c:3484 neigh_resolve_output+0x500/0x8a0 net/core/neighbour.c:1369 neigh_output include/net/neighbour.h:500 [inline] ip6_finish_output2+0x1114/0x21b0 net/ipv6/ip6_output.c:120 ip6_finish_output+0x702/0xaf0 net/ipv6/ip6_output.c:154 NF_HOOK_COND include/linux/netfilter.h:239 [inline] ip6_output+0x1c5/0x660 net/ipv6/ip6_output.c:171 dst_output include/net/dst.h:462 [inline] NF_HOOK include/linux/netfilter.h:250 [inline] ndisc_send_skb+0x88b/0x1390 net/ipv6/ndisc.c:483 ndisc_send_rs+0x125/0x630 net/ipv6/ndisc.c:677 addrconf_rs_timer+0x280/0x5a0 net/ipv6/addrconf.c:3765 call_timer_fn+0x14a/0x650 kernel/time/timer.c:1279 expire_timers+0x233/0x4d0 kernel/time/timer.c:1318 __run_timers kernel/time/timer.c:1636 [inline] run_timer_softirq+0x1d8/0x5b0 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+0x141/0x5f0 arch/x86/kernel/apic/apic.c:1102 apic_timer_interrupt+0x93/0xa0 arch/x86/entry/entry_64.S:793 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:779 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa3/0xe0 kernel/locking/spinlock.c:192 RSP: 0018:ffff88806922f8f0 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff10 RAX: 1ffffffff0f62cd1 RBX: 0000000000000282 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: 0000000000000001 RDI: 0000000000000282 RBP: ffffffff8a4c3048 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: dffffc0000000000 R13: ffff88806922f9a0 R14: ffffffff8a4c3048 R15: 0000000000000000 __debug_check_no_obj_freed lib/debugobjects.c:760 [inline] debug_check_no_obj_freed+0x27c/0x5fd lib/debugobjects.c:776 __vunmap+0x188/0x370 mm/vmalloc.c:1535 vfree+0x4b/0xd0 mm/vmalloc.c:1612 kcov_put kernel/kcov.c:104 [inline] kcov_put+0x13/0x20 kernel/kcov.c:101 kcov_close+0xc/0x10 kernel/kcov.c:188 __fput+0x25f/0x7a0 fs/file_table.c:210 task_work_run+0x113/0x190 kernel/task_work.c:113 exit_task_work include/linux/task_work.h:22 [inline] do_exit+0x9fb/0x2ae0 kernel/exit.c:858 do_group_exit+0x100/0x2e0 kernel/exit.c:955 get_signal+0x385/0x1c90 kernel/signal.c:2423 do_signal+0x7c/0x15d0 arch/x86/kernel/signal.c:814 exit_to_usermode_loop+0x160/0x200 arch/x86/entry/common.c:160 prepare_exit_to_usermode arch/x86/entry/common.c:199 [inline] syscall_return_slowpath arch/x86/entry/common.c:270 [inline] do_syscall_64+0x4a3/0x640 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x45cb19 RSP: 002b:00007f13abfbfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: 0000000000000004 RBX: 00000000004db200 RCX: 000000000045cb19 RDX: 0000000000000048 RSI: 00000000200054c0 RDI: 0000000000000005 RBP: 000000000078bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 0000000000000070 R14: 00000000004c3430 R15: 00007f13abfc06d4 device veth1_macvtap left promiscuous mode device veth0_macvtap left promiscuous mode device veth1_vlan left promiscuous mode device veth0_vlan left promiscuous mode llc_conn_state_process: llc_conn_service failed EXT4-fs (loop2): ext4_check_descriptors: Inode bitmap for group 0 overlaps superblock EXT4-fs (loop2): ext4_check_descriptors: Inode table for group 0 overlaps superblock