rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 0-....: (10467 ticks this GP) idle=5cb4/1/0x4000000000000000 softirq=44842/44884 fqs=4175 rcu: hardirqs softirqs csw/system rcu: number: 1402734 0 0 rcu: cputime: 16544 35944 48 ==> 52490(ms) rcu: (t=10500 jiffies g=62457 q=1995 ncpus=2) CPU: 0 PID: 11899 Comm: syz.1.1467 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xc0/0x120 kernel/locking/spinlock.c:194 Code: c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f7 44 24 20 00 02 00 00 41 c6 04 07 f8 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 1b 79 ce f6 65 8b 05 ec af 75 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc90000006260 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a02 RCX: 2b8e17277371b700 RDX: dffffc0000000000 RSI: ffffffff8acac900 RDI: 0000000000000001 RBP: ffffc900000062e0 R08: ffffffff911bf5c7 R09: 1ffffffff2237eb8 R10: dffffc0000000000 R11: fffffbfff2237eb9 R12: dffffc0000000000 R13: ffff88805e4a4c80 R14: ffffffff9750c1e8 R15: 1ffff92000000c4c FS: 00007ff477a446c0(0000) GS:ffff8880b8e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100000002 CR3: 000000004c9f4000 CR4: 00000000003506f0 DR0: 0000200000000300 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:999 [inline] debug_check_no_obj_freed+0x51f/0x540 lib/debugobjects.c:1020 slab_free_hook mm/slub.c:1786 [inline] slab_free_freelist_hook+0xd2/0x1a0 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 dev_queue_xmit include/linux/netdevice.h:3113 [inline] neigh_hh_output include/net/neighbour.h:527 [inline] neigh_output include/net/neighbour.h:541 [inline] ip_finish_output2+0xcec/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_ack_snd_check net/ipv4/tcp_input.c:5728 [inline] tcp_rcv_established+0xb06/0x1d20 net/ipv4/tcp_input.c:6174 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:ffffc9000bce7a00 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000 RDX: ffffc9000ee51000 RSI: 00000000000021e1 RDI: 00000000000021e2 RBP: ffffc9000bce7ad0 R08: ffffffff911bf5ff R09: 1ffffffff2237ebf R10: dffffc0000000000 R11: fffffbfff2237ec0 R12: 1ffff9200179cf44 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff9200179cf65 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: 0033:0x7ff476b9bf79 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:00007ff477a44028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007ff476e16180 RCX: 00007ff476b9bf79 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480 RBP: 00007ff476c327e0 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff476e16218 R14: 00007ff476e16180 R15: 00007fffea9fb548