rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: (detected by 0, t=10517 jiffies, g=72005, q=341 ncpus=2) rcu: All QSes seen, last rcu_preempt kthread activity 10517 (4294993874-4294983357), jiffies_till_next_fqs=1, root ->qsmask 0x0 rcu: rcu_preempt kthread starved for 10517 jiffies! g72005 f0x2 RCU_GP_WAIT_FQS(5) ->state=0x0 ->cpu=0 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:25960 pid:16 tgid:16 ppid:2 task_flags:0x208040 flags:0x00080000 Call Trace: context_switch kernel/sched/core.c:5325 [inline] __schedule+0x1798/0x4cc0 kernel/sched/core.c:6929 __schedule_loop kernel/sched/core.c:7011 [inline] schedule+0x165/0x360 kernel/sched/core.c:7026 schedule_timeout+0x12b/0x270 kernel/time/sleep_timeout.c:99 rcu_gp_fqs_loop+0x301/0x1540 kernel/rcu/tree.c:2083 rcu_gp_kthread+0x99/0x390 kernel/rcu/tree.c:2285 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 UID: 0 PID: 876 Comm: kworker/0:2 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events_power_efficient gc_worker RIP: 0010:finish_task_switch+0x26b/0x950 kernel/sched/core.c:5193 Code: 0f 84 3c 01 00 00 48 85 db 0f 85 63 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 5f ec b7 09 e8 ba bb 36 00 fb 4c 8b 65 c0 <49> 8d bc 24 58 16 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc90003667458 EFLAGS: 00000282 RAX: eeecad78d0743b00 RBX: 0000000000000000 RCX: eeecad78d0743b00 RDX: 0000000000000006 RSI: ffffffff8d70dbaf RDI: ffffffff8bbf0760 RBP: ffffc900036674b0 R08: ffffffff8f7ce277 R09: 1ffffffff1ef9c4e R10: dffffc0000000000 R11: fffffbfff1ef9c4f R12: ffff88802499dac0 R13: dffffc0000000000 R14: ffff88801ca8bc80 R15: ffff8880b883abd8 FS: 0000000000000000(0000) GS:ffff88812613b000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd152bcff8 CR3: 00000000760fa000 CR4: 00000000003526f0 Call Trace: context_switch kernel/sched/core.c:5328 [inline] __schedule+0x17a0/0x4cc0 kernel/sched/core.c:6929 preempt_schedule_irq+0xb5/0x150 kernel/sched/core.c:7256 irqentry_exit+0x6f/0x90 kernel/entry/common.c:211 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697 RIP: 0010:seqcount_lockdep_reader_access+0x17e/0x1c0 include/linux/seqlock.h:75 Code: f8 4d 85 e4 75 16 e8 11 58 4e f8 eb 15 e8 0a 58 4e f8 e8 85 b3 d4 01 4d 85 e4 74 ea e8 fb 57 4e f8 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: 0018:ffffc90003667840 EFLAGS: 00000293 RAX: ffffffff8971ae95 RBX: 0000000000000000 RCX: ffff88802499dac0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900036678f0 R08: ffffffff8f7ce277 R09: 1ffffffff1ef9c4e R10: dffffc0000000000 R11: fffffbfff1ef9c4f R12: 0000000000000200 R13: 0000000000000a71 R14: 1ffff920006ccf08 R15: dffffc0000000000 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:342 [inline] gc_worker+0x308/0x1380 net/netfilter/nf_conntrack_core.c:1548 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245