rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (1 GPs behind) idle=616c/1/0x4000000000000000 softirq=20483/20484 fqs=2986 rcu: hardirqs softirqs csw/system rcu: number: 1295884 0 0 rcu: cputime: 14316 38163 64 ==> 52500(ms) rcu: (t=10502 jiffies g=24685 q=2097 ncpus=2) CPU: 0 PID: 7854 Comm: syz.2.682 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 RIP: 0010:___slab_alloc+0x78/0x12f0 mm/slub.c:3150 Code: 48 89 44 24 58 48 85 c0 75 20 83 fd ff 74 11 48 63 c5 48 0f a3 05 50 47 53 15 0f 82 5d 03 00 00 bd ff ff ff ff e9 53 03 00 00 <48> 8b 7c 24 58 83 fd ff 0f 84 f5 00 00 00 48 8b 07 48 83 f8 ff 0f RSP: 0018:ffffc900000062c0 EFLAGS: 00000206 RAX: eacccc98a4058500 RBX: ffffffff81dec052 RCX: eacccc98a4058500 RDX: dffffc0000000000 RSI: ffffffff8acacb60 RDI: ffffffff8b1c7be0 RBP: 00000000ffffffff R08: ffffffff911bc5c7 R09: 1ffffffff22378b8 R10: dffffc0000000000 R11: fffffbfff22378b9 R12: ffff8880b8e44400 R13: ffff8880b8e443e0 R14: 0000000000000282 R15: ffff888029dfbc00 FS: 00007f33b84806c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100000000 CR3: 000000002e614000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x109/0x2c0 mm/slub.c:3519 skb_clone+0x1eb/0x370 net/core/skbuff.c:1912 dev_queue_xmit_nit+0x23f/0xba0 net/core/dev.c:2353 xmit_one net/core/dev.c:3640 [inline] dev_hard_start_xmit+0x150/0x790 net/core/dev.c:3660 sch_direct_xmit+0x251/0x4a0 net/sched/sch_generic.c:345 __dev_xmit_skb net/core/dev.c:3881 [inline] __dev_queue_xmit+0x162a/0x3630 net/core/dev.c:4416 neigh_output include/net/neighbour.h:543 [inline] ip_finish_output2+0xd97/0x1260 net/ipv4/ip_output.c:235 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip_output+0x2a5/0x3a0 net/ipv4/ip_output.c:436 dst_output include/net/dst.h:467 [inline] ip_local_out net/ipv4/ip_output.c:129 [inline] __ip_queue_xmit+0x1056/0x1960 net/ipv4/ip_output.c:540 __tcp_transmit_skb+0x1dd6/0x3470 net/ipv4/tcp_output.c:1427 tcp_transmit_skb net/ipv4/tcp_output.c:1445 [inline] tcp_write_xmit+0x1550/0x66f0 net/ipv4/tcp_output.c:2784 __tcp_push_pending_frames+0x96/0x330 net/ipv4/tcp_output.c:2969 tcp_push_pending_frames include/net/tcp.h:2012 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5658 [inline] tcp_rcv_established+0xfc5/0x1d70 net/ipv4/tcp_input.c:6092 tcp_v4_do_rcv+0x6d3/0xba0 net/ipv4/tcp_ipv4.c:1735 tcp_v4_rcv+0x2358/0x2a60 net/ipv4/tcp_ipv4.c:2167 ip_protocol_deliver_rcu+0x20a/0x3f0 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x2c3/0x510 net/ipv4/ip_input.c:233 NF_HOOK+0x32d/0x3b0 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+0xa36/0xd60 net/ipv4/ip_input.c:639 ip_list_rcv+0x3ed/0x440 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5689 [inline] __netif_receive_skb_list_core+0x582/0x770 net/core/dev.c:5737 __netif_receive_skb_list net/core/dev.c:5789 [inline] netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5880 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:580 [inline] napi_gro_receive+0x553/0xaf0 net/core/gro.c:610 receive_buf+0x219d/0x37a0 drivers/net/virtio_net.c:1870 virtnet_receive drivers/net/virtio_net.c:2155 [inline] virtnet_poll+0x60e/0x11e0 drivers/net/virtio_net.c:2229 __napi_poll+0xbb/0x460 net/core/dev.c:6650 napi_poll net/core/dev.c:6717 [inline] net_rx_action+0x65f/0xcc0 net/core/dev.c:6853 handle_softirqs+0x27d/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 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:generic_exec_single+0x477/0x4e0 kernel/smp.c:418 Code: 75 11 e8 2c 00 0b 00 48 85 db 75 16 e8 22 00 0b 00 eb 15 e8 1b 00 0b 00 e8 06 f3 07 09 48 85 db 74 ea e8 0c 00 0b 00 fb 31 c0 <48> c7 44 24 20 0e 36 e0 45 4b c7 04 2c 00 00 00 00 43 c7 44 2c 08 RSP: 0018:ffffc9000b31fa00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000 RDX: ffffc9000d04b000 RSI: 0000000000001d25 RDI: 0000000000001d26 RBP: ffffc9000b31fad0 R08: ffffffff911bc5ff R09: 1ffffffff22378bf R10: dffffc0000000000 R11: fffffbfff22378c0 R12: 1ffff92001663f44 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92001663f65 smp_call_function_single+0x36d/0x5a0 kernel/smp.c:647 task_function_call kernel/events/core.c:120 [inline] perf_install_in_context+0x5bb/0x920 kernel/events/core.c:2951 __do_sys_perf_event_open kernel/events/core.c:12949 [inline] __se_sys_perf_event_open+0x1841/0x1c60 kernel/events/core.c:12601 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f33b759ce59 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 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 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f33b8480028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f33b7815fa0 RCX: 00007f33b759ce59 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480 RBP: 00007f33b7632e6f R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f33b7816038 R14: 00007f33b7815fa0 R15: 00007ffef65af0d8