rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4221/1:b..l (detected by 0, t=10502 jiffies, g=7757, q=4) task:kworker/1:4 state:R running task stack:24256 pid: 4221 ppid: 2 flags:0x00004000 Workqueue: events_power_efficient gc_worker Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6799 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:seqcount_lockdep_reader_access+0x17b/0x1c0 include/linux/seqlock.h:106 Code: f9 4d 85 e4 75 16 e8 b4 8a 61 f9 eb 15 e8 ad 8a 61 f9 e8 e8 ad 92 01 4d 85 e4 74 ea e8 9e 8a 61 f9 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 66 43 c7 44 3e 09 00 00 43 c6 44 3e 0b 00 RSP: 0000:ffffc90003dbfa20 EFLAGS: 00000293 RAX: ffffffff88164082 RBX: 0000000000000000 RCX: ffff88806100bb80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90003dbfad0 R08: dffffc0000000000 R09: fffffbfff1ff782c R10: fffffbfff1ff782c R11: 1ffffffff1ff782b R12: 0000000000000200 R13: ffff88802254ef18 R14: 1ffff920007b7f44 R15: dffffc0000000000 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline] gc_worker+0x2e2/0x13a0 net/netfilter/nf_conntrack_core.c:1472 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread starved for 10525 jiffies! g7757 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:27008 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 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: 4414 Comm: syz.0.26 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 RIP: 0010:hlock_class kernel/locking/lockdep.c:197 [inline] RIP: 0010:mark_lock+0x9c/0x320 kernel/locking/lockdep.c:4569 Code: 89 c7 41 81 e7 ff 1f 00 00 c1 e8 03 25 f8 03 00 00 48 8d b8 c0 c0 fb 8f be 08 00 00 00 e8 5c 85 5f 00 4c 0f a3 3d 54 11 9f 0e <73> 10 4b 8d 04 7f c1 e0 06 4c 8d b8 80 3f 94 8f eb 24 48 c7 c0 80 RSP: 0018:ffffc90000dd09c0 EFLAGS: 00000057 RAX: 0000000000000001 RBX: ffff88807e248000 RCX: ffffffff815caf64 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff8ffbc0d0 RBP: 0000000000000008 R08: dffffc0000000000 R09: fffffbfff1ff781b R10: fffffbfff1ff781b R11: 1ffffffff1ff781a R12: 0000000000000100 R13: dffffc0000000000 R14: ffff88807e248b40 R15: 00000000000000a2 FS: 00007fb4c43ee6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b3241fffc CR3: 000000007a86b000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4512 [inline] __lock_acquire+0xd5a/0x7c60 kernel/locking/lockdep.c:4966 lock_acquire+0x197/0x3f0 kernel/locking/lockdep.c:5623 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0xa4/0xf0 kernel/locking/spinlock.c:162 __lock_task_sighand+0x12a/0x290 kernel/signal.c:1404 lock_task_sighand include/linux/sched/signal.h:710 [inline] do_send_sig_info kernel/signal.c:1293 [inline] group_send_sig_info+0x1ac/0x220 kernel/signal.c:1442 do_bpf_send_signal+0x7b/0x150 kernel/trace/bpf_trace.c:779 irq_work_single kernel/irq_work.c:155 [inline] irq_work_run_list+0x1bb/0x330 kernel/irq_work.c:177 irq_work_run+0x63/0xe0 kernel/irq_work.c:186 __sysvec_irq_work+0x98/0x240 arch/x86/kernel/irq_work.c:22 instr_sysvec_irq_work arch/x86/kernel/irq_work.c:17 [inline] sysvec_irq_work+0x98/0xc0 arch/x86/kernel/irq_work.c:17 asm_sysvec_irq_work+0x16/0x20 arch/x86/include/asm/idtentry.h:713 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:156 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:263 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:208 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 ff b6 c7 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc9000315fcb0 EFLAGS: 00000246 RAX: 00000000000000f6 RBX: ffffffff8bbc2a20 RCX: 000000000000083f RDX: 0000000000000000 RSI: 00000000000000f6 RDI: 000000000000083f RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed10172267af R10: ffffed10172267af R11: 1ffff110172267ae R12: ffff8880b9133b01 R13: dffffc0000000000 R14: dffffc0000000000 R15: 0000000000000020 arch_irq_work_raise+0x82/0xd0 arch/x86/kernel/irq_work.c:31 irq_work_queue+0x95/0x140 kernel/irq_work.c:75 bpf_send_signal_common+0x2b2/0x420 kernel/trace/bpf_trace.c:820 ____bpf_send_signal kernel/trace/bpf_trace.c:829 [inline] bpf_send_signal+0x15/0x20 kernel/trace/bpf_trace.c:827 bpf_prog_7ba5217f62dcd359+0x38/0x7a4 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+0x15b/0x2d0 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: 0033:0x7fb4c6143f79 Code: 64 c7 00 16 00 00 00 b8 ff ff ff ff c3 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 04 25 RSP: 002b:00007fb4c43eda80 EFLAGS: 00000246 ORIG_RAX: 000000000000000f RAX: ffffffffffffffda RBX: 00007fb4c63ff090 RCX: 00007fb4c6143f79 RDX: 00007fb4c43eda80 RSI: 00007fb4c43edbb0 RDI: 0000000000000011 RBP: 00007fb4c622af91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb4c63ff128 R14: 00007fb4c63ff090 R15: 00007ffd0410bc88