rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (10480 ticks this GP) idle=7574/1/0x4000000000000000 softirq=54478/54481 fqs=4999 rcu: hardirqs softirqs csw/system rcu: number: 1249794 19 0 rcu: cputime: 15774 36715 33 ==> 52490(ms) rcu: (t=10500 jiffies g=58765 q=2421 ncpus=2) CPU: 1 PID: 11459 Comm: syz.4.1392 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__read_once_word_nocheck+0xc/0x10 include/asm-generic/rwonce.h:67 Code: 89 e1 80 e1 07 38 c1 0f 8c 5d fc ff ff 4c 89 e7 e8 89 25 a2 00 e9 50 fc ff ff 0f 1f 40 00 53 48 89 fb e8 47 b7 4a 00 48 8b 03 <5b> c3 cc cc f3 0f 1e fa 55 48 89 e5 41 57 41 56 41 55 41 54 53 48 RSP: 0018:ffffc900001ef308 EFLAGS: 00000246 RAX: ffffffff88f0d844 RBX: ffffc900001f0018 RCX: ffff8880235cbc00 RDX: 0000000000000100 RSI: 0000000000000002 RDI: ffffc900001f0018 RBP: ffffc900001ef438 R08: ffff8880235cbc00 R09: 0000000000000003 R10: 0000000000000004 R11: 0000000000000100 R12: ffffc900001ef3e8 R13: dffffc0000000000 R14: ffffc900001f0018 R15: ffffffff8f511a18 FS: 00007efff40626c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100000000 CR3: 000000005d8ba000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000200000000300 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: deref_stack_reg arch/x86/kernel/unwind_orc.c:406 [inline] unwind_next_frame+0x15f9/0x2970 arch/x86/kernel/unwind_orc.c:585 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0x9c/0xe0 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11e/0x2e0 mm/slub.c:3519 skb_clone+0x1eb/0x370 net/core/skbuff.c:1915 neigh_probe net/core/neighbour.c:1077 [inline] __neigh_event_send+0xe9c/0x14c0 net/core/neighbour.c:1247 neigh_event_send_probe include/net/neighbour.h:467 [inline] neigh_event_send include/net/neighbour.h:473 [inline] neigh_resolve_output+0x19b/0x730 net/core/neighbour.c:1552 neigh_output include/net/neighbour.h:543 [inline] ip_finish_output2+0xd21/0x11d0 net/ipv4/ip_output.c:235 dst_output include/net/dst.h:467 [inline] ip_local_out net/ipv4/ip_output.c:129 [inline] __ip_queue_xmit+0x10aa/0x1a10 net/ipv4/ip_output.c:535 __tcp_transmit_skb+0x1c97/0x32a0 net/ipv4/tcp_output.c:1422 tcp_validate_incoming+0xf13/0x2250 net/ipv4/tcp_input.c:5891 tcp_rcv_established+0x7d8/0x1cf0 net/ipv4/tcp_input.c:6156 tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1734 tcp_v4_rcv+0x2334/0x2a50 net/ipv4/tcp_ipv4.c:2166 ip_protocol_deliver_rcu+0x20e/0x3f0 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2ca/0x510 net/ipv4/ip_input.c:233 NF_HOOK+0x303/0x390 include/linux/netfilter.h:304 dst_input include/net/dst.h:477 [inline] ip_sublist_rcv_finish net/ipv4/ip_input.c:580 [inline] ip_list_rcv_finish net/ipv4/ip_input.c:631 [inline] ip_sublist_rcv+0xa38/0xd20 net/ipv4/ip_input.c:639 ip_list_rcv+0x3e3/0x430 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5651 [inline] __netif_receive_skb_list_core+0x2cc/0x740 net/core/dev.c:5689 __netif_receive_skb_list net/core/dev.c:5751 [inline] netif_receive_skb_list_internal+0x91b/0xc60 net/core/dev.c:5842 gro_normal_list include/net/gro.h:451 [inline] gro_normal_one include/net/gro.h:464 [inline] napi_skb_finish net/core/gro.c:573 [inline] napi_gro_receive+0x565/0xb00 net/core/gro.c:603 receive_buf+0x218c/0x3780 drivers/net/virtio_net.c:1870 virtnet_receive drivers/net/virtio_net.c:2155 [inline] virtnet_poll+0x61f/0x1180 drivers/net/virtio_net.c:2229 __napi_poll+0xc0/0x460 net/core/dev.c:6612 napi_poll net/core/dev.c:6679 [inline] net_rx_action+0x5ea/0xbf0 net/core/dev.c:6815 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:finish_task_switch+0x26a/0x920 kernel/sched/core.c:5254 Code: 0f 84 37 01 00 00 48 85 db 0f 85 56 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 80 ca 14 09 e8 4b a4 2f 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc9000c86f738 EFLAGS: 00000282 RAX: 9c0fb26ba51f2f00 RBX: 0000000000000000 RCX: 9c0fb26ba51f2f00 RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6f80 RBP: ffffc9000c86f790 R08: ffffffff8e4a212f R09: 1ffffffff1c94425 R10: dffffc0000000000 R11: fffffbfff1c94426 R12: ffff8880235cbc00 R13: dffffc0000000000 R14: ffff88801f2bda00 R15: ffff8880b8f3cac8 context_switch kernel/sched/core.c:5383 [inline] __schedule+0x14da/0x44d0 kernel/sched/core.c:6699 preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7009 irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:preempt_schedule+0x0/0xc0 kernel/sched/core.c:6883 Code: 4c 89 f7 e8 42 48 6d f7 eb af 66 0f 1f 00 bf 01 00 00 00 e8 72 b8 eb f6 e8 fd fd ff ff bf 01 00 00 00 e8 c3 b6 eb f6 c3 66 90 0f 1e fa 55 48 89 e5 41 56 53 48 83 e4 e0 48 83 ec 60 65 48 8b RSP: 0018:ffffc9000c86fb10 EFLAGS: 00000246 RAX: 0000000000000000 RBX: ffff8880b8f3cd58 RCX: 0000000000000000 RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: 00000000ffffffff RBP: ffffc9000c86fb60 R08: ffffffff8e4a212f R09: 1ffffffff1c94425 R10: dffffc0000000000 R11: fffffbfff1c94426 R12: 0000000000000001 R13: dffffc0000000000 R14: 0000000000000001 R15: dffffc0000000000 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 class_preempt_destructor include/linux/preempt.h:478 [inline] try_to_wake_up+0x756/0x1140 kernel/sched/core.c:4355 wake_up_process kernel/sched/core.c:4480 [inline] wake_up_q+0xb6/0x100 kernel/sched/core.c:1031 futex_wake+0x40d/0x4b0 kernel/futex/waitwake.c:184 do_futex+0x35d/0x3e0 kernel/futex/syscalls.c:139 __do_sys_futex kernel/futex/syscalls.c:211 [inline] __se_sys_futex+0x36f/0x3f0 kernel/futex/syscalls.c:192 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7efff318f749 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:00007efff40620e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca RAX: ffffffffffffffda RBX: 00007efff33e5fa8 RCX: 00007efff318f749 RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007efff33e5fac RBP: 00007efff33e5fa0 R08: 00000000007459b5 R09: 0000000000000000 R10: 0000000000000009 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efff33e6038 R14: 00007fffc2d087f0 R15: 00007fffc2d088d8