rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=2304/1/0x4000000000000000 softirq=17141/17142 fqs=4412 rcu: hardirqs softirqs csw/system rcu: number: 1359644 0 0 rcu: cputime: 19190 33298 69 ==> 52490(ms) rcu: (t=10500 jiffies g=18357 q=606 ncpus=2) CPU: 1 PID: 7117 Comm: syz.3.365 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] RIP: 0010:_raw_spin_unlock_irqrestore+0xa9/0x110 kernel/locking/spinlock.c:194 Code: 74 05 e8 0a d9 1a f7 48 c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4b f7 c3 00 02 00 00 74 01 fb bf 01 00 00 00 e2 53 ea f6 65 8b 05 d3 9a 92 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900001efea0 EFLAGS: 00000206 RAX: 28d2cbffd3e90100 RBX: 0000000000000a06 RCX: 28d2cbffd3e90100 RDX: dffffc0000000000 RSI: ffffffff8aaabce0 RDI: 0000000000000001 RBP: ffffc900001eff38 R08: ffffffff90d945ef R09: 1ffffffff21b28bd R10: dffffc0000000000 R11: fffffbfff21b28be R12: dffffc0000000000 R13: ffff888023daed80 R14: ffffffff9715e758 R15: 1ffff9200003dfd4 FS: 00007f19cb70e6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c2b203c CR3: 0000000024473000 CR4: 00000000003506e0 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+0xd2/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x280 mm/slub.c:3852 skb_kfree_head net/core/skbuff.c:947 [inline] skb_free_head net/core/skbuff.c:961 [inline] skb_release_data+0x60a/0x800 net/core/skbuff.c:991 skb_release_all net/core/skbuff.c:1057 [inline] __kfree_skb net/core/skbuff.c:1071 [inline] kfree_skb_reason+0x10e/0x170 net/core/skbuff.c:1107 kfree_skb include/linux/skbuff.h:1232 [inline] ip_tunnel_xmit+0xe5d/0x2360 net/ipv4/ip_tunnel.c:-1 __gre_xmit net/ipv4/ip_gre.c:478 [inline] gre_tap_xmit+0x4fe/0x6f0 net/ipv4/ip_gre.c:757 __netdev_start_xmit include/linux/netdevice.h:4943 [inline] netdev_start_xmit include/linux/netdevice.h:4957 [inline] xmit_one net/core/dev.c:3619 [inline] dev_hard_start_xmit+0x246/0x740 net/core/dev.c:3635 sch_direct_xmit+0x252/0x4a0 net/sched/sch_generic.c:345 __dev_xmit_skb net/core/dev.c:3856 [inline] __dev_queue_xmit+0x173e/0x35a0 net/core/dev.c:4391 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] ip6_finish_output2+0xdf5/0x1650 net/ipv6/ip6_output.c:141 dst_output include/net/dst.h:467 [inline] NF_HOOK include/linux/netfilter.h:304 [inline] ndisc_send_skb+0xbed/0x14b0 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x2bc/0x600 net/ipv6/addrconf.c:4006 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x52d/0x7d0 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 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:generic_exec_single+0x476/0x4f0 kernel/smp.c:418 Code: 75 11 e8 cd e6 0a 00 48 85 db 75 16 e8 c3 e6 0a 00 eb 15 e8 bc e6 0a 00 e8 47 cd ec 08 48 85 db 74 ea e8 ad e6 0a 00 fb 31 c0 <48> c7 44 24 20 0e 36 e0 45 4b c7 04 2c 00 00 00 00 66 43 c7 44 2c RSP: 0018:ffffc90005a7f860 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 0000000000000200 RCX: 0000000000080000 RDX: ffffc9000cea9000 RSI: 0000000000000f2c RDI: 0000000000000f2d RBP: ffffc90005a7f930 R08: ffffffff90d945ff R09: 1ffffffff21b28bf R10: dffffc0000000000 R11: fffffbfff21b28c0 R12: 1ffff92000b4ff10 R13: dffffc0000000000 R14: 0000000000000000 R15: 1ffff92000b4ff31 smp_call_function_single+0x352/0x580 kernel/smp.c:647 task_function_call kernel/events/core.c:120 [inline] event_function_call+0x31f/0x5f0 kernel/events/core.c:305 _perf_event_period kernel/events/core.c:5904 [inline] _perf_ioctl kernel/events/core.c:5973 [inline] perf_ioctl+0x1fff/0x2440 kernel/events/core.c:6074 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 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: 0033:0x7f19ca78f749 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:00007f19cb70e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f19ca9e5fa0 RCX: 00007f19ca78f749 RDX: 0000200000000300 RSI: 0000000040082404 RDI: 0000000000000006 RBP: 00007f19ca813f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f19ca9e6038 R14: 00007f19ca9e5fa0 R15: 00007ffd642f75e8