rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=b684/1/0x4000000000000000 softirq=12193/12194 fqs=4233 rcu: hardirqs softirqs csw/system rcu: number: 1534990 2 0 rcu: cputime: 18298 34171 57 ==> 52470(ms) rcu: (t=10500 jiffies g=10701 q=1626 ncpus=2) CPU: 1 PID: 6163 Comm: syz.0.91 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 RIP: 0010:_raw_spin_lock_irqsave+0xa/0x100 kernel/locking/spinlock.c:161 Code: 00 00 45 31 c9 ff 74 24 08 e8 62 5e d8 f6 48 83 c4 08 48 89 df 5b e9 65 b1 d9 f6 0f 1f 44 00 00 f3 0f 1e fa 55 48 89 e5 41 57 <41> 56 41 54 53 48 83 e4 e0 48 83 ec 60 48 89 fb 65 48 8b 04 25 28 RSP: 0018:ffffc900001f0798 EFLAGS: 00000206 RAX: 00000000000001f0 RBX: ffffffff974784d0 RCX: 61c8864680b583eb RDX: dffffc0000000000 RSI: 00000000000000f0 RDI: ffffffff974784d8 RBP: ffffc900001f07a0 R08: ffff888025610000 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000100 R12: ffff88802b3cfaf0 R13: ffff88802b3cfa00 R14: ffff88802b3cf000 R15: 0000000000000001 FS: 00007f8c768f36c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000100000000 CR3: 000000005cadd000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000600 Call Trace: __debug_check_no_obj_freed lib/debugobjects.c:979 [inline] debug_check_no_obj_freed+0x13a/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 kfree_skb include/linux/skbuff.h:1264 [inline] ip6_mc_input+0xaa0/0xcb0 net/ipv6/ip6_input.c:589 NF_HOOK+0x32d/0x3b0 include/linux/netfilter.h:304 __netif_receive_skb_one_core net/core/dev.c:5634 [inline] __netif_receive_skb+0xcc/0x290 net/core/dev.c:5748 process_backlog+0x391/0x6f0 net/core/dev.c:6076 __napi_poll+0xc0/0x460 net/core/dev.c:6638 napi_poll net/core/dev.c:6705 [inline] net_rx_action+0x616/0xc40 net/core/dev.c:6841 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:preempt_schedule_irq+0xba/0x150 kernel/sched/core.c:7010 Code: 00 00 43 c6 44 37 04 f8 74 0b 0f 0b 48 f7 03 08 00 00 00 74 6f bf 01 00 00 00 e8 a1 1b ce f6 e8 cc 28 ff f6 fb bf 01 00 00 00 f1 b4 ff ff 43 c6 44 37 08 00 48 c7 44 24 40 00 00 00 00 9c 8f RSP: 0018:ffffc90005b2fbe0 EFLAGS: 00000282 RAX: 56fdebe2a2146c00 RBX: 0000000000000000 RCX: 56fdebe2a2146c00 RDX: dffffc0000000000 RSI: ffffffff8acac9e0 RDI: 0000000000000001 RBP: ffffc90005b2fc80 R08: ffffffff911c45ff R09: 1ffffffff22388bf R10: dffffc0000000000 R11: fffffbfff22388c0 R12: 0000000000000000 R13: 0000000000000000 R14: dffffc0000000000 R15: 1ffff92000b65f7c 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:__do_sys_perf_event_open kernel/events/core.c:12958 [inline] RIP: 0010:__se_sys_perf_event_open+0x1839/0x1c50 kernel/events/core.c:12609 Code: fc ff df 0f b6 04 08 84 c0 0f 85 02 03 00 00 48 8b 74 24 20 8b 96 fc 02 00 00 48 8b 5c 24 28 48 89 df e8 ba 3f 00 00 48 89 df 92 3a ff ff 48 8b 7c 24 48 e8 38 90 df 08 80 7c 24 17 00 74 07 RSP: 0018:ffffc90005b2fd40 EFLAGS: 00000246 RAX: 56fdebe2a2146c00 RBX: ffff88801b7e4400 RCX: 0000000000080000 RDX: ffffc9000d6fa000 RSI: 0000000000006aa8 RDI: ffff88801b7e4400 RBP: ffffc90005b2ff10 R08: ffffffff911c45ff R09: 1ffffffff22388bf R10: dffffc0000000000 R11: fffffbfff22388c0 R12: 0000000000000000 R13: 1ffff92000b65fb8 R14: ffff88801b670230 R15: ffff888025610000 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: 0033:0x7f8c7599c819 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:00007f8c768f3028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f8c75c15fa0 RCX: 00007f8c7599c819 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480 RBP: 00007f8c75a32c91 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8c75c16038 R14: 00007f8c75c15fa0 R15: 00007fff1ef85798