rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { 0-.... } 2856 jiffies s: 1693 root: 0x1/. rcu: blocking rcu_node structures (internal RCU debug): Sending NMI from CPU 1 to CPUs 0: NMI backtrace for cpu 0 CPU: 0 PID: 4448 Comm: syz.3.20 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:native_apic_msr_eoi_write+0xb/0x10 arch/x86/include/asm/apic.h:212 Code: 8b 06 bf f0 03 00 00 89 de 5b 41 5e 41 5f ff e0 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b9 0b 08 00 00 31 c0 31 d2 0f 30 0f 1f 40 00 81 ff cf 00 00 00 7f 0c 83 ff 20 74 2a 83 ff 30 74 RSP: 0018:ffffc90000007348 EFLAGS: 00000046 RAX: 0000000000000000 RBX: ffffffff8c5e4b30 RCX: 000000000000080b RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000000b0 RBP: 0000000000000000 R08: ffffffff8f9f7008 R09: ffffffff8f9f7018 R10: ffffffff8f9f7010 R11: ffffffff8f9f7003 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007faa082276c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f814ff8 CR3: 000000005975e000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_eoi arch/x86/include/asm/apic.h:399 [inline] ack_APIC_irq arch/x86/include/asm/apic.h:445 [inline] __sysvec_apic_timer_interrupt+0x81/0x5a0 arch/x86/kernel/apic/apic.c:1122 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0x4d/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:ipv6_skip_exthdr+0x55f/0x670 net/ipv6/exthdrs_core.c:113 Code: fd ff ff e8 03 c2 87 f8 eb 0c e8 fc c1 87 f8 eb 05 e8 f5 c1 87 f8 bb ff ff ff ff 48 ba 00 00 00 00 00 fc ff df 4c 8b 74 24 10 <48> c7 44 24 60 0e 36 e0 45 49 c7 04 16 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc90000007440 EFLAGS: 00000297 RAX: 000000000000003a RBX: 0000000000000028 RCX: 0000000000007500 RDX: dffffc0000000000 RSI: ffffffff8de692f0 RDI: 000000000000003a RBP: ffffc90000007530 R08: ffff88802cf29dc0 R09: 0000000000000006 R10: 000000000000003c R11: 0000000000000100 R12: ffff8880292d5218 R13: 000000000000003a R14: 1ffff92000000e94 R15: ffffc900000075b0 ipv6_get_l4proto net/netfilter/nf_conntrack_core.c:397 [inline] get_l4proto+0x235/0x640 net/netfilter/nf_conntrack_core.c:420 nf_conntrack_in+0x294/0x1770 net/netfilter/nf_conntrack_core.c:2011 nf_hook_entry_hookfn include/linux/netfilter.h:142 [inline] nf_hook_slow+0xb9/0x200 net/netfilter/core.c:614 nf_hook include/linux/netfilter.h:257 [inline] NF_HOOK+0x200/0x390 include/linux/netfilter.h:300 __netif_receive_skb_one_core net/core/dev.c:5581 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5695 process_backlog+0x37c/0x6e0 net/core/dev.c:6023 __napi_poll+0xc0/0x460 net/core/dev.c:6590 napi_poll net/core/dev.c:6657 [inline] net_rx_action+0x5b1/0xad0 net/core/dev.c:6771 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:preempt_schedule_irq+0xac/0x150 kernel/sched/core.c:6873 Code: 44 24 20 f6 44 24 21 02 74 0b 0f 0b 48 f7 03 08 00 00 00 74 70 bf 01 00 00 00 e8 7f cf 37 f7 e8 7a 47 67 f7 fb bf 01 00 00 00 df b9 ff ff 48 c7 44 24 40 00 00 00 00 9c 8f 44 24 40 8b 44 24 RSP: 0018:ffffc90004cff200 EFLAGS: 00000286 RAX: 604b417ae986df00 RBX: 0000000000000000 RCX: 604b417ae986df00 RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: 0000000000000001 RBP: ffffc90004cff2a0 R08: dffffc0000000000 R09: ffffed10171c6afa R10: ffffed10171c6afa R11: 1ffff110171c6af9 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff9200099fe40 irqentry_exit+0x63/0x70 kernel/entry/common.c:439 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 RIP: 0010:should_resched arch/x86/include/asm/preempt.h:103 [inline] RIP: 0010:__local_bh_enable_ip+0x132/0x1b0 kernel/softirq.c:428 Code: 8a e8 42 e7 c8 08 65 66 8b 05 8a 2e b5 7e 66 85 c0 75 54 bf 01 00 00 00 e8 7b 44 09 00 e8 e6 ba 38 00 fb 65 8b 05 76 fd b3 7e <85> c0 75 05 e8 c5 0e b2 ff 48 c7 04 24 0e 36 e0 45 4b c7 04 37 00 RSP: 0018:ffffc90004cff360 EFLAGS: 00000286 RAX: 0000000000000000 RBX: 0000000000000201 RCX: 604b417ae986df00 RDX: dffffc0000000000 RSI: ffffffff8a8c0500 RDI: ffffffff8adefca0 RBP: ffffc90004cff3f8 R08: dffffc0000000000 R09: ffffed10171c6afa R10: ffffed10171c6afa R11: 1ffff110171c6af9 R12: ffffffff88265a6c R13: 00000000ffffacda R14: dffffc0000000000 R15: 1ffff9200099fe6c neigh_forced_gc net/core/neighbour.c:294 [inline] neigh_alloc net/core/neighbour.c:486 [inline] ___neigh_create+0x5fc/0x24c0 net/core/neighbour.c:649 ip6_finish_output2+0x14f0/0x1590 net/ipv6/ip6_output.c:129 dst_output include/net/dst.h:453 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] rawv6_send_hdrinc+0xe40/0x1750 net/ipv6/raw.c:654 rawv6_sendmsg+0x1179/0x1730 net/ipv6/raw.c:912 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x59b/0x970 net/socket.c:2519 ___sys_sendmsg+0x21c/0x290 net/socket.c:2573 __sys_sendmsg net/socket.c:2602 [inline] __do_sys_sendmsg net/socket.c:2611 [inline] __se_sys_sendmsg+0x19e/0x270 net/socket.c:2609 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7faa0738eba9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007faa08227038 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007faa075d5fa0 RCX: 00007faa0738eba9 RDX: 0000000000000000 RSI: 0000200000000000 RDI: 0000000000000008 RBP: 00007faa07411e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007faa075d6038 R14: 00007faa075d5fa0 R15: 00007ffef70dfd68