rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-...!: (1 GPs behind) idle=9ae/1/0x4000000000000002 softirq=14771/14772 fqs=15 (t=10502 jiffies g=5937 q=18) rcu: rcu_preempt kthread starved for 10473 jiffies! g5937 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=1 rcu: RCU grace-period kthread stack dump: rcu_preempt I29016 10 2 0x80004000 Call Trace: context_switch kernel/sched/core.c:3385 [inline] __schedule+0x87f/0xcd0 kernel/sched/core.c:4081 schedule+0x188/0x210 kernel/sched/core.c:4155 schedule_timeout+0x14f/0x240 kernel/time/timer.c:1895 rcu_gp_fqs_loop kernel/rcu/tree.c:1661 [inline] rcu_gp_kthread+0xe0d/0x1770 kernel/rcu/tree.c:1821 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: 8580 Comm: syz-executor207 Not tainted 5.5.0-rc7-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:455 [inline] check_cpu_stall kernel/rcu/tree_stall.h:529 [inline] rcu_pending kernel/rcu/tree.c:2827 [inline] rcu_sched_clock_irq+0x1521/0x1ab0 kernel/rcu/tree.c:2271 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:1110 [inline] smp_apic_timer_interrupt+0x109/0x280 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:hash_ip4_expire+0x1f1/0x870 net/netfilter/ipset/ip_set_hash_gen.h:475 Code: 48 85 c0 0f 84 80 04 00 00 48 89 9d 68 ff ff ff 48 89 45 c8 48 8d 50 19 48 89 d0 48 c1 e8 03 48 89 85 70 ff ff ff 42 8a 04 30 <84> c0 48 89 55 d0 0f 85 a0 05 00 00 0f b6 1a 31 ff 89 de e8 27 38 RSP: 0018:ffffc90001db7038 EFLAGS: 00000a02 ORIG_RAX: ffffffffffffff13 RAX: 1ffff11012feba00 RBX: 1ffff11011363faf RCX: ffff88808e34c540 RDX: ffff888097f5d719 RSI: 0000000000000000 RDI: 0000000000000003 RBP: ffffc90001db7118 R08: ffffffff86a74cc1 R09: ffffed1012febb03 R10: ffffed1012febb03 R11: 0000000000000000 R12: ffff888089b1fd78 R13: ffff888089b00008 R14: dffffc0000000000 R15: ffff888089b00000 hash_ip4_add+0x147/0x1500 net/netfilter/ipset/ip_set_hash_gen.h:709 hash_ip4_uadt+0x589/0x810 net/netfilter/ipset/ip_set_hash_ip.c:151 call_ad+0x10a/0x5b0 net/netfilter/ipset/ip_set_core.c:1716 ip_set_ad+0x6a9/0x860 net/netfilter/ipset/ip_set_core.c:1804 ip_set_uadd+0x37/0x50 net/netfilter/ipset/ip_set_core.c:1829 nfnetlink_rcv_msg+0x9ae/0xcd0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x19e/0x3e0 net/netlink/af_netlink.c:2477 nfnetlink_rcv+0x1e0/0x1e50 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x767/0x920 net/netlink/af_netlink.c:1328 netlink_sendmsg+0xa2c/0xd50 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg net/socket.c:659 [inline] ____sys_sendmsg+0x4f7/0x7f0 net/socket.c:2330 ___sys_sendmsg net/socket.c:2384 [inline] __sys_sendmsg+0x1ed/0x290 net/socket.c:2417 __do_sys_sendmsg net/socket.c:2426 [inline] __se_sys_sendmsg net/socket.c:2424 [inline] __x64_sys_sendmsg+0x7f/0x90 net/socket.c:2424 do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x441579 Code: e8 fc ab 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 9b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fff97ce2e68 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441579 RDX: 0000000000000000 RSI: 0000000020000d00 RDI: 0000000000000004 RBP: 0000000000040767 R08: 00000000004002c8 R09: 00000000004002c8 R10: 00000000004002c8 R11: 0000000000000246 R12: 00000000004023a0 R13: 0000000000402430 R14: 0000000000000000 R15: 0000000000000000