rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (10500 ticks this GP) idle=24dc/1/0x4000000000000000 softirq=71735/71736 fqs=4719 rcu: hardirqs softirqs csw/system rcu: number: 1293698 0 0 rcu: cputime: 17726 34763 50 ==> 52500(ms) rcu: (t=10502 jiffies g=83725 q=1585 ncpus=2) CPU: 1 PID: 20411 Comm: syz.7.3755 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:unwind_next_frame+0x38/0x2970 arch/x86/kernel/unwind_orc.c:470 Code: 48 81 ec 98 00 00 00 49 89 fc 49 bd 00 00 00 00 00 fc ff df e8 59 dd 4b 00 49 8d 5c 24 48 48 89 d8 48 c1 e8 03 48 89 44 24 40 <42> 80 3c 28 00 74 08 48 89 df e8 49 06 a4 00 48 89 5c 24 20 4d 8b RSP: 0018:ffffc900001eecd8 EFLAGS: 00000a06 RAX: 1ffff9200003ddbe RBX: ffffc900001eedf0 RCX: ffff8880193bbc00 RDX: 0000000000000100 RSI: ffffffff890176a3 RDI: ffffc900001eeda8 RBP: ffffc900001eee30 R08: ffffc900001eee70 R09: 0000000000000011 R10: 0000000000000004 R11: 0000000000000100 R12: ffffc900001eeda8 R13: dffffc0000000000 R14: ffffffff8175b740 R15: ffffc900001eeda8 FS: 00007f0490e936c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0490e71ff8 CR3: 00000000367b6000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000008d24 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x270 mm/slub.c:3852 dev_kfree_skb_any_reason+0x120/0x130 net/core/dev.c:3241 free_old_xmit_skbs+0x11a/0x3d0 drivers/net/virtio_net.c:780 start_xmit+0x161/0x1410 drivers/net/virtio_net.c:2420 __netdev_start_xmit include/linux/netdevice.h:4943 [inline] netdev_start_xmit include/linux/netdevice.h:4957 [inline] xmit_one net/core/dev.c:3632 [inline] dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3648 sch_direct_xmit+0x25e/0x4c0 net/sched/sch_generic.c:345 __dev_xmit_skb net/core/dev.c:3869 [inline] __dev_queue_xmit+0x179c/0x36b0 net/core/dev.c:4404 neigh_output include/net/neighbour.h:543 [inline] ip_finish_output2+0xd3a/0x11e0 net/ipv4/ip_output.c:235 NF_HOOK_COND include/linux/netfilter.h:293 [inline] ip_output+0x2a1/0x3b0 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+0x1049/0x1950 net/ipv4/ip_output.c:540 __tcp_transmit_skb+0x1cbd/0x32f0 net/ipv4/tcp_output.c:1422 tcp_transmit_skb net/ipv4/tcp_output.c:1440 [inline] tcp_write_xmit+0x174c/0x62e0 net/ipv4/tcp_output.c:2778 __tcp_push_pending_frames+0x97/0x340 net/ipv4/tcp_output.c:2963 tcp_push_pending_frames include/net/tcp.h:2012 [inline] tcp_data_snd_check net/ipv4/tcp_input.c:5656 [inline] tcp_rcv_established+0xab3/0x1d20 net/ipv4/tcp_input.c:6173 tcp_v4_do_rcv+0x4ed/0xb80 net/ipv4/tcp_ipv4.c:1734 tcp_v4_rcv+0x23bf/0x2af0 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+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+0xa4c/0xd70 net/ipv4/ip_input.c:639 ip_list_rcv+0x3f2/0x440 net/ipv4/ip_input.c:674 __netif_receive_skb_list_ptype net/core/dev.c:5664 [inline] __netif_receive_skb_list_core+0x583/0x750 net/core/dev.c:5712 __netif_receive_skb_list net/core/dev.c:5764 [inline] netif_receive_skb_list_internal+0x943/0xca0 net/core/dev.c:5855 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:575 [inline] napi_gro_receive+0x565/0xb00 net/core/gro.c:605 receive_buf+0x2203/0x3820 drivers/net/virtio_net.c:1870 virtnet_receive drivers/net/virtio_net.c:2155 [inline] virtnet_poll+0x5dd/0x1280 drivers/net/virtio_net.c:2229 __napi_poll+0xc0/0x460 net/core/dev.c:6625 napi_poll net/core/dev.c:6692 [inline] net_rx_action+0x616/0xc40 net/core/dev.c:6828 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+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+0x481/0x4f0 kernel/smp.c:418 Code: 75 11 e8 02 02 0b 00 48 85 db 75 16 e8 f8 01 0b 00 eb 15 e8 f1 01 0b 00 e8 cc 4a 08 09 48 85 db 74 ea e8 e2 01 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:ffffc900043ffa00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000 RDX: ffffc9000fe4b000 RSI: 0000000000007c1d RDI: 0000000000007c1e RBP: ffffc900043ffad0 R08: ffffffff911bf5ff R09: 1ffffffff2237ebf R10: dffffc0000000000 R11: fffffbfff2237ec0 R12: 1ffff9200087ff44 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff9200087ff65 smp_call_function_single+0x36d/0x5a0 kernel/smp.c:647 task_function_call kernel/events/core.c:120 [inline] perf_install_in_context+0x5be/0x920 kernel/events/core.c:2948 __do_sys_perf_event_open kernel/events/core.c:12915 [inline] __se_sys_perf_event_open+0x1836/0x1c50 kernel/events/core.c:12567 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f048ff9c629 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:00007f0490e93028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f0490215fa0 RCX: 00007f048ff9c629 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000140 RBP: 00007f0490032b39 R08: 0000000000000002 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0490216038 R14: 00007f0490215fa0 R15: 00007ffcab503588