rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6460/1:b..l P4602/1:b..l P6459/1:b..l (detected by 0, t=10502 jiffies, g=27077, q=46) task:dhcpcd-run-hook state:R running task stack:27200 pid: 6459 ppid: 3840 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6552 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6577 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __raw_spin_unlock include/linux/spinlock_api_smp.h:152 [inline] _raw_spin_unlock+0x36/0x40 kernel/locking/spinlock.c:186 spin_unlock include/linux/spinlock.h:403 [inline] filemap_map_pages+0x1031/0x1390 mm/filemap.c:3353 do_fault_around mm/memory.c:4243 [inline] do_read_fault mm/memory.c:4258 [inline] do_fault mm/memory.c:4392 [inline] handle_pte_fault mm/memory.c:4650 [inline] __handle_mm_fault mm/memory.c:4785 [inline] handle_mm_fault+0x2580/0x43c0 mm/memory.c:4883 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357 handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7f49a19fe9b0 RSP: 002b:00007fff95b3dc98 EFLAGS: 00010206 RAX: 00007f49a18c17e8 RBX: 0000006bf2799822 RCX: 00007f49a18c17e8 RDX: 00007f49a19fe9b0 RSI: 00007f49a1b80980 RDI: 0000000000000001 RBP: 00007fff95b3df50 R08: 0000000000000000 R09: 000000000000000e R10: fffffffffffff68e R11: 0000000000000206 R12: fffffffffffffff8 R13: 0000006bf14aa6f7 R14: 0000000000000000 R15: 00007f49a1b8d310 task:kworker/1:8 state:R running task stack:25856 pid: 4602 ppid: 2 flags:0x00004000 Workqueue: events_power_efficient gc_worker Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681 RIP: 0010:seqcount_lockdep_reader_access+0x17b/0x1c0 include/linux/seqlock.h:106 Code: f9 4d 85 e4 75 16 e8 e4 13 69 f9 eb 15 e8 dd 13 69 f9 e8 78 be 92 01 4d 85 e4 74 ea e8 ce 13 69 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: 0018:ffffc9000150fa20 EFLAGS: 00000293 RAX: ffffffff880eae52 RBX: 0000000000000000 RCX: ffff88801da89dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000150fad0 R08: dffffc0000000000 R09: fffffbfff1ff362c R10: fffffbfff1ff362c R11: 1ffffffff1ff362b R12: 0000000000000200 R13: ffff888024d27618 R14: 1ffff920002a1f44 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 task:syz-executor state:R running task stack:27584 pid: 6460 ppid: 4158 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 preempt_schedule_irq+0xb1/0x150 kernel/sched/core.c:6780 irqentry_exit+0x63/0x70 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681 RIP: 0010:rcu_lock_acquire+0x1d/0x30 include/linux/rcupdate.h:312 Code: 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 e8 0b d4 c9 ff e8 06 d4 c9 ff 48 c7 c7 a0 bf 11 8c 31 f6 31 d2 b9 02 00 00 00 45 31 c0 <45> 31 c9 68 15 ee ad 81 e8 46 f7 ad ff 48 83 c4 08 c3 90 e8 db d3 RSP: 0000:ffffc9000368fbf8 EFLAGS: 00000246 RAX: ffffffff81adee1a RBX: 0000000000000014 RCX: 0000000000000002 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff8c11bfa0 RBP: ffffc9000368fcb0 R08: 0000000000000000 R09: ffffed1003a5b8d8 R10: ffffed1003a5b8d8 R11: 1ffff11003a5b8d7 R12: dffffc0000000000 R13: 1ffff920006d1f80 R14: ffff88801d2dc600 R15: 00007fce4eb64050 rcu_read_lock include/linux/rcupdate.h:740 [inline] count_memcg_event_mm+0x87/0x360 include/linux/memcontrol.h:1078 handle_mm_fault+0x12d/0x43c0 mm/memory.c:4863 do_user_addr_fault+0x489/0xc80 arch/x86/mm/fault.c:1357 handle_page_fault arch/x86/mm/fault.c:1445 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1501 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7fce4ea01b44 RSP: 002b:00007ffdbeba19d0 EFLAGS: 00010202 RAX: 00007fce4e873660 RBX: 00007fce4e8a3258 RCX: 00007fce4ebe0700 RDX: 00007fce4ea7b680 RSI: 00007fce4e85b3c0 RDI: 00007fce4eb64050 RBP: 00007fce4ebe0700 R08: 0000000000048288 R09: 00007fce4e8a3648 R10: 0000000070000025 R11: 00007fce4e85b3a0 R12: 00007ffdbeba1a10 R13: 00007ffdbeba1b98 R14: 00007ffdbeba1b30 R15: 00007fce4e85b000 rcu: rcu_preempt kthread starved for 10570 jiffies! g27077 f0x0 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:28032 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 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: NMI backtrace for cpu 0 CPU: 0 PID: 0 Comm: swapper/0 Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 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_check_gp_kthread_starvation+0x1cd/0x250 kernel/rcu/tree_stall.h:487 print_other_cpu_stall+0x10c8/0x1220 kernel/rcu/tree_stall.h:592 check_cpu_stall kernel/rcu/tree_stall.h:745 [inline] rcu_pending kernel/rcu/tree.c:3932 [inline] rcu_sched_clock_irq+0x831/0x1110 kernel/rcu/tree.c:2619 update_process_times+0x193/0x200 kernel/time/timer.c:1818 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:1690 [inline] __hrtimer_run_queues+0x4fe/0xc40 kernel/time/hrtimer.c:1754 hrtimer_interrupt+0x3bb/0x8d0 kernel/time/hrtimer.c:1816 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 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:default_idle+0xb/0x10 arch/x86/kernel/process.c:723 Code: bf 48 89 df e8 26 8c 12 f8 eb b5 e8 3f be f6 ff 00 00 cc cc 00 00 cc cc 00 00 cc cc 00 00 cc 66 90 0f 00 2d 97 13 5b 00 fb f4 0f 1f 40 00 41 57 41 56 53 49 be 00 00 00 00 00 fc ff df 65 48 RSP: 0018:ffffffff8be07dc8 EFLAGS: 000002c6 RAX: faf19784a682bd00 RBX: ffffffff8bebc3c0 RCX: faf19784a682bd00 RDX: 0000000000000001 RSI: ffffffff8a0b11c0 RDI: ffffffff8a59a740 RBP: ffffffff8be07ef8 R08: dffffc0000000000 R09: ffffed101720765a R10: ffffed101720765a R11: 1ffff11017207659 R12: ffffffff8d68abe8 R13: 0000000000000000 R14: 0000000000000000 R15: 1ffffffff17d7878 default_idle_call+0x81/0xc0 kernel/sched/idle.c:112 cpuidle_idle_call kernel/sched/idle.c:194 [inline] do_idle+0x21b/0x5b0 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_kernel+0x486/0x530 init/main.c:1140 secondary_startup_64_no_verify+0xb1/0xbb