rcu: INFO: rcu_preempt self-detected stall on CPU rcu: 1-....: (1 GPs behind) idle=06e4/1/0x4000000000000000 softirq=17016/17017 fqs=5247 rcu: hardirqs softirqs csw/system rcu: number: 1238441 0 0 rcu: cputime: 15723 36765 80 ==> 52500(ms) rcu: (t=10502 jiffies g=19485 q=762 ncpus=2) CPU: 1 PID: 7051 Comm: syz.0.326 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 0b c9 cd f6 65 8b 05 2c f8 74 75 85 c0 74 3c 48 c7 04 24 0e 36 RSP: 0018:ffffc900001f0720 EFLAGS: 00000206 RAX: dffffc0000000004 RBX: 0000000000000a06 RCX: eaca08291b178100 RDX: dffffc0000000000 RSI: ffffffff8acac960 RDI: 0000000000000001 RBP: ffffc900001f07b8 R08: ffffffff911c15c7 R09: 1ffffffff22382b8 R10: dffffc0000000000 R11: fffffbfff22382b9 R12: dffffc0000000000 R13: ffff88804ff68000 R14: ffffffff974e3a40 R15: 1ffff9200003e0e4 FS: 00007f3859f406c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00002000001e7000 CR3: 000000002de9e000 CR4: 00000000003506e0 DR0: 0000000000000000 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 free_pages_prepare mm/page_alloc.c:1187 [inline] free_unref_page_prepare+0x1da/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 napi_frag_unref include/linux/skbuff.h:3539 [inline] skb_release_data+0x49a/0x800 net/core/skbuff.c:985 skb_release_all net/core/skbuff.c:1057 [inline] __kfree_skb+0x57/0x70 net/core/skbuff.c:1071 tcp_write_queue_purge+0x143/0x2f0 net/ipv4/tcp.c:3006 tcp_done_with_error+0x43/0xc0 net/ipv4/tcp_input.c:4446 tcp_write_err net/ipv4/tcp_timer.c:72 [inline] tcp_write_timeout net/ipv4/tcp_timer.c:281 [inline] tcp_retransmit_timer+0x1728/0x3020 net/ipv4/tcp_timer.c:576 tcp_write_timer+0x12a/0x280 net/ipv4/tcp_timer.c:709 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x542/0x800 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+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:finish_task_switch+0x26a/0x8f0 kernel/sched/core.c:5255 Code: 0f 84 33 01 00 00 48 85 db 0f 85 52 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 00 54 31 09 e8 9b 23 30 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc90018e97498 EFLAGS: 00000282 RAX: eaca08291b178100 RBX: 0000000000000000 RCX: eaca08291b178100 RDX: dffffc0000000000 RSI: ffffffff8acac960 RDI: ffffffff8b1c85a0 RBP: ffffc90018e974f0 R08: ffffffff911c152f R09: 1ffffffff22382a5 R10: dffffc0000000000 R11: fffffbfff22382a6 R12: ffff88805e990000 R13: dffffc0000000000 R14: ffff888028d6bc00 R15: ffff8880b8f3cac8 context_switch kernel/sched/core.c:5384 [inline] __schedule+0x155b/0x45a0 kernel/sched/core.c:6700 preempt_schedule_common+0x82/0xc0 kernel/sched/core.c:6867 preempt_schedule+0xc0/0xd0 kernel/sched/core.c:6891 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk_64.S:45 __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock_irqrestore+0x111/0x120 kernel/locking/spinlock.c:194 __debug_check_no_obj_freed lib/debugobjects.c:999 [inline] debug_check_no_obj_freed+0x51f/0x540 lib/debugobjects.c:1020 free_pages_prepare mm/page_alloc.c:1187 [inline] free_unref_page_prepare+0x1da/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x319/0x400 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] kmem_cache_alloc_node+0x14c/0x320 mm/slub.c:3540 perf_event_alloc+0x15a/0x21b0 kernel/events/core.c:12057 __do_sys_perf_event_open kernel/events/core.c:12676 [inline] __se_sys_perf_event_open+0x740/0x1c50 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: 0033:0x7f3858f9c799 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:00007f3859f40028 EFLAGS: 00000246 ORIG_RAX: 000000000000012a RAX: ffffffffffffffda RBX: 00007f3859215fa0 RCX: 00007f3858f9c799 RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000200000000480 RBP: 00007f3859032bd9 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffffffffffff R11: 0000000000000246 R12: 0000000000000000 R13: 00007f3859216038 R14: 00007f3859215fa0 R15: 00007ffed6875e78