rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P969/1:b..l rcu: (detected by 0, t=10503 jiffies, g=9245, q=27 ncpus=2) task:kworker/1:2 state:R running task stack:25896 pid:969 ppid:2 flags:0x00004000 Workqueue: events_power_efficient gc_worker Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 preempt_schedule_irq+0xbf/0x150 kernel/sched/core.c:7011 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:seqcount_lockdep_reader_access+0x19a/0x1d0 include/linux/seqlock.h:105 Code: f8 4d 85 e4 75 16 e8 a5 5f c3 f8 eb 15 e8 9e 5f c3 f8 e8 49 c0 c8 01 4d 85 e4 74 ea e8 8f 5f c3 f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3e 00 00 00 00 43 c7 44 3e 08 00 00 00 00 65 48 8b 04 25 RSP: 0018:ffffc9000386f9a0 EFLAGS: 00000293 RAX: ffffffff88c41541 RBX: 0000000000000000 RCX: ffff888022818000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000386fa50 R08: ffffffff911eb597 R09: 1ffffffff223d6b2 R10: dffffc0000000000 R11: fffffbfff223d6b3 R12: 0000000000000200 R13: dffffc0000000000 R14: 1ffff9200070df34 R15: dffffc0000000000 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:350 [inline] gc_worker+0x314/0x14a0 net/netfilter/nf_conntrack_core.c:1461 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa60/0x1600 kernel/workqueue.c:2730 worker_thread+0xa5e/0xfe0 kernel/workqueue.c:2811 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 rcu: rcu_preempt kthread starved for 10529 jiffies! g9245 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:27848 pid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5382 [inline] __schedule+0x15ae/0x4660 kernel/sched/core.c:6701 schedule+0xbd/0x170 kernel/sched/core.c:6775 schedule_timeout+0x188/0x2d0 kernel/time/timer.c:2168 rcu_gp_fqs_loop+0x30d/0x1590 kernel/rcu/tree.c:1667 rcu_gp_kthread+0x9d/0x3b0 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 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: 5788 Comm: syz-executor100 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:19 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:89 [inline] RIP: 0010:__might_resched+0x169/0x5f0 kernel/sched/core.c:10176 Code: 00 00 48 89 d3 48 c1 eb 03 42 0f b6 04 2b 84 c0 0f 85 49 03 00 00 8b 02 c1 e0 08 44 01 e0 3b 44 24 2c 75 72 43 c6 44 2f 0c 00 <48> c7 84 24 a0 00 00 00 00 00 00 00 9c 8f 84 24 a0 00 00 00 f7 84 RSP: 0018:ffffc90004637a80 EFLAGS: 00000246 RAX: 0000000000000000 RBX: 1ffff11006000447 RCX: a6275d087c2d3700 RDX: ffff88803000223c RSI: ffffffff8acadd60 RDI: ffffffff8b1d0660 RBP: ffffc90004637b98 R08: ffffc90004637e2f R09: 1ffff920008c6fc5 R10: dffffc0000000000 R11: fffff520008c6fc6 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff888030001e00 R15: 1ffff920008c6f58 FS: 00007fdaf162f6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000000058 CR3: 000000007c862000 CR4: 00000000003506e0 Call Trace: __might_fault+0x71/0x120 mm/memory.c:5966 __clear_user arch/x86/include/asm/uaccess_64.h:167 [inline] clear_user arch/x86/include/asm/uaccess_64.h:191 [inline] copy_siginfo_to_user+0x5b/0xa0 kernel/signal.c:3375 x64_setup_rt_frame+0x749/0xc30 arch/x86/kernel/signal_64.c:194 setup_rt_frame arch/x86/kernel/signal.c:223 [inline] handle_signal arch/x86/kernel/signal.c:267 [inline] arch_do_signal_or_restart+0x411/0x7b0 arch/x86/kernel/signal.c:312 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fdaf16504d7 Code: 00 85 c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d0 ff ff ff f7 d8 64 89 RSP: 002b:00007fdaf162f178 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007fdaf16ffb28 RCX: 00007fdaf16504d9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007fdaf16ffb28 RBP: 00007fdaf16ffb20 R08: 00007fdaf162fcdc R09: 00007fdaf162fcdc R10: 0000000000000000 R11: 0000000000000246 R12: 00007fdaf16ffb2c R13: 0000000000000000 R14: 00007ffd2acfed90 R15: 00007ffd2acfee78