rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (10500 ticks this GP) idle=346/1/0x4000000000000004 softirq=16541/16541 fqs=0 (t=10500 jiffies g=9269 q=1075) rcu: rcu_preempt kthread starved for 10500 jiffies! g9269 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0 rcu: RCU grace-period kthread stack dump: rcu_preempt I28984 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3380 [inline] __schedule+0x87f/0xcd0 kernel/sched/core.c:4080 schedule+0x188/0x210 kernel/sched/core.c:4154 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1658 [inline] rcu_gp_kthread+0xe8d/0x17e0 kernel/rcu/tree.c:1818 kthread+0x332/0x350 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 NMI backtrace for cpu 0 CPU: 0 PID: 9045 Comm: syz-executor.1 Not tainted 5.6.0-rc3-syzkaller #0 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+0x1fb/0x318 lib/dump_stack.c:118 nmi_cpu_backtrace+0xaa/0x190 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x16f/0x290 lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x10/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x15a/0x220 kernel/rcu/tree_stall.h:254 print_cpu_stall kernel/rcu/tree_stall.h:475 [inline] check_cpu_stall kernel/rcu/tree_stall.h:549 [inline] rcu_pending kernel/rcu/tree.c:3030 [inline] rcu_sched_clock_irq+0x1521/0x1aa0 kernel/rcu/tree.c:2276 update_process_times+0x12d/0x180 kernel/time/timer.c:1726 tick_sched_handle kernel/time/tick-sched.c:171 [inline] tick_sched_timer+0x263/0x420 kernel/time/tick-sched.c:1314 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x3f3/0x840 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x37c/0xda0 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1119 [inline] smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1144 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:unwind_next_frame+0x34d/0x7a0 arch/x86/kernel/unwind_frame.c:301 Code: 5d c0 4c 8b 6d 88 4d 8d 75 50 4c 89 f3 48 c1 eb 03 49 bf 00 00 00 00 00 fc ff df 42 80 3c 3b 00 74 08 4c 89 f7 e8 63 d5 7e 00 <4d> 8b 26 4d 85 e4 74 18 42 80 3c 3b 00 74 08 4c 89 f7 e8 ec d5 7e RSP: 0018:ffffc90000006d38 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: ffffc90002bc7f30 RBX: 1ffff92000000dc6 RCX: ffffffff8977b000 RDX: dffffc0000000000 RSI: ffffffff86d9e487 RDI: ffffc90002bc7f48 RBP: ffffc90000006dd0 R08: ffffc90000006e88 R09: 0000000000000009 R10: ffffc90000006e90 R11: 0000000000000000 R12: ffffc90002bc7f58 R13: ffffc90000006de0 R14: ffffc90000006e30 R15: dffffc0000000000 arch_stack_walk+0xb4/0xe0 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xb1/0x150 kernel/stacktrace.c:123 save_stack mm/kasan/common.c:72 [inline] set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc+0x118/0x1c0 mm/kasan/common.c:515 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:523 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slab.c:3263 [inline] kmem_cache_alloc_node+0x235/0x280 mm/slab.c:3575 __alloc_skb+0x9f/0x500 net/core/skbuff.c:198 alloc_skb include/linux/skbuff.h:1081 [inline] ip_frag_next+0xdf/0xa20 net/ipv4/ip_output.c:697 ip_do_fragment+0x892/0x1d30 net/ipv4/ip_output.c:894 ip_fragment+0x11f/0x210 net/ipv4/ip_output.c:585 __ip_finish_output+0x401/0x4b0 net/ipv4/ip_output.c:304 ip_finish_output+0x52/0x1e0 net/ipv4/ip_output.c:316 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip_output+0x217/0x290 net/ipv4/ip_output.c:430 dst_output include/net/dst.h:436 [inline] ip_local_out+0x105/0x130 net/ipv4/ip_output.c:125 iptunnel_xmit+0x45f/0x7e0 net/ipv4/ip_tunnel_core.c:81 udp_tunnel_xmit_skb+0x1b6/0x2c0 net/ipv4/udp_tunnel.c:192 geneve_xmit_skb drivers/net/geneve.c:929 [inline] geneve_xmit+0x1800/0x1f70 drivers/net/geneve.c:1004 __netdev_start_xmit include/linux/netdevice.h:4523 [inline] netdev_start_xmit include/linux/netdevice.h:4537 [inline] xmit_one net/core/dev.c:3475 [inline] dev_hard_start_xmit+0x1b1/0x3f0 net/core/dev.c:3491 __dev_queue_xmit+0x1c07/0x2930 net/core/dev.c:4050 dev_queue_xmit+0x17/0x20 net/core/dev.c:4083 neigh_hh_output include/net/neighbour.h:499 [inline] neigh_output include/net/neighbour.h:508 [inline] ip6_finish_output2+0x101d/0x13e0 net/ipv6/ip6_output.c:116 __ip6_finish_output+0x693/0x8c0 net/ipv6/ip6_output.c:142 ip6_finish_output+0x52/0x1e0 net/ipv6/ip6_output.c:152 NF_HOOK_COND include/linux/netfilter.h:296 [inline] ip6_output+0x2c2/0x3c0 net/ipv6/ip6_output.c:175 dst_output include/net/dst.h:436 [inline] NF_HOOK include/linux/netfilter.h:307 [inline] ndisc_send_skb+0xa33/0xe20 net/ipv6/ndisc.c:505 ndisc_send_rs+0x4f9/0x680 net/ipv6/ndisc.c:699 addrconf_rs_timer+0x235/0x6b0 net/ipv6/addrconf.c:3879 call_timer_fn+0x95/0x170 kernel/time/timer.c:1404 expire_timers kernel/time/timer.c:1449 [inline] __run_timers+0x776/0x970 kernel/time/timer.c:1773 run_timer_softirq+0x4a/0x90 kernel/time/timer.c:1786 __do_softirq+0x283/0x7bd kernel/softirq.c:292 invoke_softirq kernel/softirq.c:373 [inline] irq_exit+0x227/0x230 kernel/softirq.c:413 exiting_irq arch/x86/include/asm/apic.h:546 [inline] smp_apic_timer_interrupt+0x113/0x280 arch/x86/kernel/apic/apic.c:1146 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:arch_local_irq_restore arch/x86/include/asm/paravirt.h:752 [inline] RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:160 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa8/0xe0 kernel/locking/spinlock.c:191 Code: b9 00 00 00 00 00 fc ff df 80 3c 08 00 74 0c 48 c7 c7 10 d3 2a 89 e8 37 2e 9a f9 48 83 3d 4f ce 10 01 00 74 2d 4c 89 f7 57 9d <0f> 1f 44 00 00 bf 01 00 00 00 e8 f9 32 39 f9 65 8b 05 ee 18 e8 77 RSP: 0018:ffffc90002bc6a30 EFLAGS: 00000282 ORIG_RAX: ffffffffffffff13 RAX: 1ffffffff1255a62 RBX: ffffffff8a695788 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: 0000000000000282 RBP: ffffc90002bc6a40 R08: ffff888046c20d18 R09: fffffbfff140651c R10: fffffbfff140651c R11: 0000000000000000 R12: ffff88809c0b44f8 R13: ffff88808b4c5818 R14: 0000000000000282 R15: 1ffff11011698b01 __debug_object_init+0x885/0x19d0 lib/debugobjects.c:580 debug_object_init lib/debugobjects.c:595 [inline] debug_object_activate+0x17a/0x6f0 lib/debugobjects.c:681 debug_rcu_head_queue kernel/rcu/rcu.h:176 [inline] __call_rcu kernel/rcu/tree.c:2597 [inline] call_rcu+0x3a/0x660 kernel/rcu/tree.c:2683 alias_free_mem_rcu net/ipv4/fib_trie.c:304 [inline] fib_table_delete+0x107e/0x12b0 net/ipv4/fib_trie.c:1710 fib_magic+0x459/0x5e0 net/ipv4/fib_frontend.c:1084 fib_del_ifaddr+0x1008/0x1490 net/ipv4/fib_frontend.c:1285 fib_inetaddr_event+0xca/0x340 net/ipv4/fib_frontend.c:1425 notifier_call_chain kernel/notifier.c:83 [inline] __blocking_notifier_call_chain+0x171/0x250 kernel/notifier.c:284 blocking_notifier_call_chain+0x2d/0x40 kernel/notifier.c:295 __inet_del_ifa+0x8ce/0x1060 net/ipv4/devinet.c:427 inet_del_ifa net/ipv4/devinet.c:464 [inline] inetdev_destroy net/ipv4/devinet.c:317 [inline] inetdev_event+0x57a/0x13b0 net/ipv4/devinet.c:1593 notifier_call_chain kernel/notifier.c:83 [inline] __raw_notifier_call_chain kernel/notifier.c:361 [inline] raw_notifier_call_chain+0xe3/0x190 kernel/notifier.c:368 call_netdevice_notifiers_info net/core/dev.c:1948 [inline] call_netdevice_notifiers_mtu net/core/dev.c:1997 [inline] dev_set_mtu_ext+0x4dd/0x830 net/core/dev.c:8283 do_setlink+0x7c4/0x3880 net/core/rtnetlink.c:2559 rtnl_group_changelink net/core/rtnetlink.c:3103 [inline] __rtnl_newlink net/core/rtnetlink.c:3257 [inline] rtnl_newlink+0x10b2/0x1c00 net/core/rtnetlink.c:3377 rtnetlink_rcv_msg+0x889/0xd40 net/core/rtnetlink.c:5436 netlink_rcv_skb+0x19e/0x3e0 net/netlink/af_netlink.c:2478 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5454 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x766/0x920 net/netlink/af_netlink.c:1329 netlink_sendmsg+0xa2b/0xd40 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg net/socket.c:672 [inline] ____sys_sendmsg+0x4f7/0x7f0 net/socket.c:2343 ___sys_sendmsg net/socket.c:2397 [inline] __sys_sendmsg+0x1ed/0x290 net/socket.c:2430 __do_sys_sendmsg net/socket.c:2439 [inline] __se_sys_sendmsg net/socket.c:2437 [inline] __x64_sys_sendmsg+0x7f/0x90 net/socket.c:2437 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: ad b6 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fbcc6180c78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fbcc61816d4 RCX: 000000000045c449 RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000004 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000009f9 R14: 00000000004cc6fa R15: 000000000076bf2c