rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P8472
rcu: 	(detected by 0, t=10502 jiffies, g=33629, q=326 ncpus=2)
task:syz.4.465       state:R  running task     stack:20008 pid:8472  ppid:6860   flags:0x00004002
Call Trace:
 <IRQ>
 sched_show_task+0x481/0x5a0 kernel/sched/core.c:9178
 rcu_print_detail_task_stall_rnp kernel/rcu/tree_stall.h:261 [inline]
 print_other_cpu_stall+0xfa7/0x1340 kernel/rcu/tree_stall.h:637
 check_cpu_stall kernel/rcu/tree_stall.h:809 [inline]
 rcu_pending kernel/rcu/tree.c:3950 [inline]
 rcu_sched_clock_irq+0x87c/0x1220 kernel/rcu/tree.c:2295
 update_process_times+0x147/0x1b0 kernel/time/timer.c:2071
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x3a2/0x580 kernel/time/tick-sched.c:1492
 __run_hrtimer kernel/time/hrtimer.c:1750 [inline]
 __hrtimer_run_queues+0x4df/0xc40 kernel/time/hrtimer.c:1814
 hrtimer_interrupt+0x3c9/0x9c0 kernel/time/hrtimer.c:1876
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1077 [inline]
 __sysvec_apic_timer_interrupt+0xfb/0x3b0 arch/x86/kernel/apic/apic.c:1094
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline]
 sysvec_apic_timer_interrupt+0x9f/0xc0 arch/x86/kernel/apic/apic.c:1088
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687
RIP: 0010:check_kcov_mode kernel/kcov.c:193 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x36/0x60 kernel/kcov.c:216
Code: 20 28 7e 7e 65 8b 15 21 28 7e 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc
RSP: 0018:ffffc9000c587a68 EFLAGS: 00000246
RAX: ffffffff819efdd4 RBX: ffffffff819efd92 RCX: ffff888024353c00
RDX: 0000000000000002 RSI: ffffffff8afc6ae0 RDI: ffffffff8afc6aa0
RBP: 0000000000000001 R08: dffffc0000000000 R09: 1ffffffff21b50a0
R10: dffffc0000000000 R11: fffffbfff21b50a1 R12: ffffc9000bb1b030
R13: ffffc9000c587d00 R14: ffffc9000c587aa8 R15: dffffc0000000000
 rcu_read_lock include/linux/rcupdate.h:787 [inline]
 ____bpf_get_current_ancestor_cgroup_id kernel/bpf/helpers.c:427 [inline]
 bpf_get_current_ancestor_cgroup_id+0x64/0x3f0 kernel/bpf/helpers.c:421
 bpf_prog_9c7e806b7014fbbd+0x45/0x47
 bpf_dispatcher_nop_func include/linux/bpf.h:1224 [inline]
 __bpf_prog_run include/linux/filter.h:612 [inline]
 bpf_prog_run include/linux/filter.h:619 [inline]
 bpf_test_run+0x2c7/0x810 net/bpf/test_run.c:424
 bpf_prog_test_run_skb+0xa67/0x11c0 net/bpf/test_run.c:1050
 bpf_prog_test_run+0x321/0x390 kernel/bpf/syscall.c:4129
 __sys_bpf+0x440/0x800 kernel/bpf/syscall.c:5491
 __do_sys_bpf kernel/bpf/syscall.c:5577 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5575 [inline]
 __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5575
 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: 0033:0x7fbc17f8f6c9
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:00007fbc18e3e038 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007fbc181e6090 RCX: 00007fbc17f8f6c9
RDX: 0000000000000050 RSI: 00002000000002c0 RDI: 000000000000000a
RBP: 00007fbc18011f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbc181e6128 R14: 00007fbc181e6090 R15: 00007ffe55ec4048
 </TASK>
rcu: rcu_preempt kthread starved for 10388 jiffies! g33629 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=1
rcu: 	Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:R  running task     stack:27112 pid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5380 [inline]
 __schedule+0x14d2/0x44d0 kernel/sched/core.c:6699
 schedule+0xbd/0x170 kernel/sched/core.c:6773
 schedule_timeout+0x160/0x280 kernel/time/timer.c:2167
 rcu_gp_fqs_loop+0x302/0x1560 kernel/rcu/tree.c:1667
 rcu_gp_kthread+0x99/0x380 kernel/rcu/tree.c:1866
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 0 Comm: swapper/1 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
RIP: 0010:pv_native_safe_halt+0x13/0x20 arch/x86/kernel/paravirt.c:148
Code: cc cc cc cc cc cc cc f3 0f 1e fa 0f 0b 66 2e 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 66 90 0f 00 2d c3 64 39 00 f3 0f 1e fa fb f4 <c3> cc cc cc cc cc cc cc cc cc cc cc cc 66 0f 1f 00 55 41 57 41 56
RSP: 0018:ffffc90000187de0 EFLAGS: 000002c2
RAX: d8bdfc1c36f72700 RBX: ffffffff816187ab RCX: d8bdfc1c36f72700
RDX: 0000000000000001 RSI: ffffffff8aaabce0 RDI: ffffffff8afc6b00
RBP: ffffc90000187f20 R08: ffff8880b8f36b2b R09: 1ffff110171e6d65
R10: dffffc0000000000 R11: ffffed10171e6d66 R12: ffffffff8e4a8d68
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff1100364e780
FS:  0000000000000000(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f9525c7374c CR3: 000000002e98d000 CR4: 00000000003506e0
Call Trace:
 <TASK>
 arch_safe_halt arch/x86/include/asm/paravirt.h:108 [inline]
 default_idle+0x13/0x20 arch/x86/kernel/process.c:753
 default_idle_call+0x6c/0xa0 kernel/sched/idle.c:97
 cpuidle_idle_call kernel/sched/idle.c:170 [inline]
 do_idle+0x1eb/0x510 kernel/sched/idle.c:282
 cpu_startup_entry+0x43/0x60 kernel/sched/idle.c:380
 start_secondary+0xee/0xf0 arch/x86/kernel/smpboot.c:323
 secondary_startup_64_no_verify+0x179/0x17b
 </TASK>