rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=86e/1/0x4000000000000002 softirq=16299/16301 fqs=5207 (t=10500 jiffies g=9489 q=80) NMI backtrace for cpu 1 CPU: 1 PID: 9708 Comm: syz-executor976 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+0x197/0x210 lib/dump_stack.c:118 nmi_cpu_backtrace.cold+0x70/0xb2 lib/nmi_backtrace.c:101 nmi_trigger_cpumask_backtrace+0x23b/0x28b lib/nmi_backtrace.c:62 arch_trigger_cpumask_backtrace+0x14/0x20 arch/x86/kernel/apic/hw_nmi.c:38 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline] rcu_dump_cpu_stacks+0x183/0x1cf 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.cold+0x509/0xc0d kernel/rcu/tree.c:2271 update_process_times+0x2d/0x70 kernel/time/timer.c:1726 tick_sched_handle+0xa2/0x190 kernel/time/tick-sched.c:171 tick_sched_timer+0x53/0x140 kernel/time/tick-sched.c:1314 __run_hrtimer kernel/time/hrtimer.c:1517 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1579 hrtimer_interrupt+0x314/0x770 kernel/time/hrtimer.c:1641 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1110 [inline] smp_apic_timer_interrupt+0x160/0x610 arch/x86/kernel/apic/apic.c:1135 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:829 RIP: 0010:debug_lockdep_rcu_enabled.part.0+0x3b/0x60 kernel/rcu/update.c:251 Code: 8b 1c 25 c0 1e 02 00 48 8d bb 94 08 00 00 48 89 fa 48 c1 ea 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 10 <8b> 93 94 08 00 00 31 c0 5b 5d 85 d2 0f 94 c0 c3 e8 40 8b 51 00 eb RSP: 0018:ffffc90002066ed8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 RAX: 0000000000000007 RBX: ffff88808e400400 RCX: 1ffffffff14f6ffe RDX: 0000000000000000 RSI: ffffffff8676b150 RDI: ffff88808e400c94 RBP: ffffc90002066ee0 R08: 0000000000000001 R09: ffffc90002066f18 R10: fffff5200040cde5 R11: ffffc90002066f2f R12: ffffc90002067040 R13: 00000000bfffffff R14: ffffc90002067020 R15: ffffc90002067020 debug_lockdep_rcu_enabled+0x71/0xa0 kernel/rcu/update.c:251 hash_ip4_del+0x83/0xce0 net/netfilter/ipset/ip_set_hash_gen.h:847 hash_ip4_uadt+0x546/0x7a0 net/netfilter/ipset/ip_set_hash_ip.c:151 call_ad+0x1a0/0x5a0 net/netfilter/ipset/ip_set_core.c:1716 ip_set_ad.isra.0+0x572/0xb20 net/netfilter/ipset/ip_set_core.c:1804 ip_set_udel+0x3a/0x50 net/netfilter/ipset/ip_set_core.c:1838 nfnetlink_rcv_msg+0xcf2/0xfb0 net/netfilter/nfnetlink.c:229 netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 nfnetlink_rcv+0x1ba/0x460 net/netfilter/nfnetlink.c:563 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917 sock_sendmsg_nosec net/socket.c:639 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:659 ____sys_sendmsg+0x753/0x880 net/socket.c:2330 ___sys_sendmsg+0x100/0x170 net/socket.c:2384 __sys_sendmsg+0x105/0x1d0 net/socket.c:2417 __compat_sys_sendmsg net/compat.c:642 [inline] __do_compat_sys_sendmsg net/compat.c:649 [inline] __se_compat_sys_sendmsg net/compat.c:646 [inline] __ia32_compat_sys_sendmsg+0x7a/0xb0 net/compat.c:646 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline] do_fast_syscall_32+0x27b/0xe16 arch/x86/entry/common.c:408 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 RIP: 0023:0xf7fa89a9 Code: 00 00 00 89 d3 5b 5e 5f 5d c3 b8 80 96 98 00 eb c4 8b 04 24 c3 8b 1c 24 c3 8b 34 24 c3 8b 3c 24 c3 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000ffd98fdc EFLAGS: 00000202 ORIG_RAX: 0000000000000172 RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000020000080 RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00000000ffd990f4 RBP: 00000000ffd990fc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000