rcu: INFO: rcu_preempt self-detected stall on CPU
rcu: 	1-....: (1 GPs behind) idle=7bb/1/0x4000000000000000 softirq=10478/10479 fqs=4297 
	(t=10500 jiffies g=12493 q=188)
NMI backtrace for cpu 1
CPU: 1 PID: 5355 Comm: syz.0.58 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <IRQ>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x3a2/0x3d0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_dump_cpu_stacks+0x22f/0x380 kernel/rcu/tree_stall.h:349
 print_cpu_stall+0x31d/0x5f0 kernel/rcu/tree_stall.h:633
 check_cpu_stall kernel/rcu/tree_stall.h:727 [inline]
 rcu_pending kernel/rcu/tree.c:3936 [inline]
 rcu_sched_clock_irq+0x6ea/0x1120 kernel/rcu/tree.c:2619
 update_process_times+0x193/0x200 kernel/time/timer.c:2021
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x37d/0x560 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x4b4/0xb70 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x137/0x4a0 arch/x86/kernel/apic/apic.c:1114
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline]
 sysvec_apic_timer_interrupt+0x9b/0xc0 arch/x86/kernel/apic/apic.c:1108
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676
RIP: 0010:__refcount_add include/linux/refcount.h:198 [inline]
RIP: 0010:__refcount_inc include/linux/refcount.h:250 [inline]
RIP: 0010:refcount_inc include/linux/refcount.h:267 [inline]
RIP: 0010:get_task_struct include/linux/sched/task.h:107 [inline]
RIP: 0010:bpf_send_signal_common+0x21d/0x420 kernel/trace/bpf_trace.c:817
Code: cb 00 00 00 4c 8d a3 48 3b 03 00 4d 89 fd 49 83 c5 28 4c 89 ef be 04 00 00 00 e8 5e 30 3b 00 bb 01 00 00 00 f0 41 0f c1 5f 28 <31> ff 89 de e8 3a 13 f6 ff 85 db 0f 84 1e 01 00 00 bf fe ff ff 7f
RSP: 0018:ffffc9000135fd00 EFLAGS: 00000202
RAX: ffffffff81832401 RBX: 0000000000000001 RCX: ffffffff818324a2
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffff8880766c8028
RBP: ffffc9000135fdc0 R08: ffff8880766c802b R09: 1ffff1100ecd9005
R10: dffffc0000000000 R11: ffffed100ecd9006 R12: ffff8880b9133b48
R13: ffff8880766c8028 R14: 1ffff9200026bfa4 R15: ffff8880766c8000
 ____bpf_send_signal kernel/trace/bpf_trace.c:829 [inline]
 bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:827
 bpf_prog_7ba5217f62dcd359+0x38/0x21c
 bpf_dispatcher_nop_func include/linux/bpf.h:888 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 __bpf_trace_run kernel/trace/bpf_trace.c:1878 [inline]
 bpf_trace_run2+0x163/0x2e0 kernel/trace/bpf_trace.c:1915
 __bpf_trace_sys_enter+0x60/0x70 include/trace/events/syscalls.h:18
 trace_sys_enter+0x65/0x80 include/trace/events/syscalls.h:18
 syscall_trace_enter+0x115/0x180 kernel/entry/common.c:77
 do_syscall_64+0x24/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f559c81a959
Code: 11 06 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 90 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 c7 c0 0f 00 00 00 0f 05 <0f> 1f 80 00 00 00 00 48 81 ec 48 01 00 00 49 89 d0 64 48 8b 0c 25
RSP: 002b:00007f559bedcb40 EFLAGS: 00000246 ORIG_RAX: 000000000000000f
RAX: ffffffffffffffda RBX: 00007f559cae4fa8 RCX: 00007f559c81a959
RDX: 00007f559bedcb40 RSI: 00007f559bedcc70 RDI: 0000000000000011
RBP: 00007f559cae4fa0 R08: 002f9c1e51f57deb R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f559cae5038 R14: 00007fff6b3cdda0 R15: 00007fff6b3cde88
 </TASK>