rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P5714/1:b..l P23/1:b..l (detected by 0, t=10503 jiffies, g=11877, q=553) task:kworker/1:1 state:R running task stack:25248 pid: 23 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 84 38 61 f9 eb 15 e8 7d 38 61 f9 e8 48 da 92 01 4d 85 e4 74 ea e8 6e 38 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: 0018:ffffc90000ddfa20 EFLAGS: 00000293 RAX: ffffffff881693a2 RBX: 0000000000000000 RCX: ffff888017610000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000ddfad0 R08: dffffc0000000000 R09: fffffbfff1ff7c2c R10: fffffbfff1ff7c2c R11: 1ffffffff1ff7c2b R12: 0000000000000200 R13: ffff88807934ea80 R14: 1ffff920001bbf44 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.0.440 state:R running task stack:27520 pid: 5714 ppid: 4183 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5049 [inline] __schedule+0x11bb/0x4390 kernel/sched/core.c:6395 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6571 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6596 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:404 [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+0x257d/0x43b0 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: 0033:0x7f21c98ff23d RSP: 002b:00007fffbd19b970 EFLAGS: 00010202 RAX: 000000110c2c0000 RBX: 00007f21ca7a5720 RCX: 0000000000000007 RDX: 00000000000016f8 RSI: 00000000000024db RDI: 0000000000000080 RBP: ffffffff889936f8 R08: 00007f21c9c76038 R09: 00007f21c9c62000 R10: 00007f21c948f008 R11: 0000000000000001 R12: 0000000000000001 R13: 0000000000000000 R14: ffffffff88993b15 R15: 0000000000000135 rcu: rcu_preempt kthread starved for 10542 jiffies! g11877 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:28160 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: 5717 Comm: syz.2.439 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 RIP: 0010:clockevents_program_event+0x196/0x310 kernel/time/clockevents.c:333 Code: c0 0f 85 55 01 00 00 4d 0f af f5 45 8b 3f bf 40 00 00 00 44 89 fe e8 59 3f 0d 00 49 83 ff 3f 0f 87 55 01 00 00 e8 ea 3b 0d 00 <44> 89 f9 49 d3 ee 48 8d 7b 08 48 89 f8 48 c1 e8 03 42 80 3c 20 00 RSP: 0018:ffffc90000dd0e70 EFLAGS: 00000006 RAX: ffffffff816a9026 RBX: ffff8880b9127280 RCX: ffff88801e351dc0 RDX: 0000000000010000 RSI: 0000000000000020 RDI: 0000000000000040 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ad33a6 R10: fffffbfff1ad33a6 R11: 1ffffffff1ad33a5 R12: dffffc0000000000 R13: 0000000010007215 R14: 00037bdaa6575861 R15: 0000000000000020 FS: 00007f767c1fb6c0(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000006b000 CR3: 00000000750be000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: hrtimer_interrupt+0x4de/0x8d0 kernel/time/hrtimer.c:1824 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:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:169 [inline] RIP: 0010:_raw_spin_unlock_irq+0x25/0x40 kernel/locking/spinlock.c:202 Code: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 de 9e a9 f7 48 89 df e8 a6 73 aa f7 e8 41 0d cb f7 fb bf 01 00 00 00 76 95 9e f7 65 8b 05 07 93 4f 76 85 c0 74 02 5b c3 e8 b4 9d 4d RSP: 0018:ffffc9000307fbc0 EFLAGS: 00000282 RAX: b5f952f3fefa1800 RBX: ffff888023a09bc0 RCX: b5f952f3fefa1800 RDX: dffffc0000000000 RSI: ffffffff8a0b1c60 RDI: 0000000000000001 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed1004741379 R10: ffffed1004741379 R11: 1ffff11004741378 R12: ffff888023a09bc0 R13: 0000000000000021 R14: dffffc0000000000 R15: 000000001c000004 spin_unlock_irq include/linux/spinlock.h:414 [inline] get_signal+0x11d6/0x12c0 kernel/signal.c:2903 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:178 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f767df946c7 Code: ff ff 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 RSP: 002b:00007f767c1fb0e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007f767e1eafa8 RCX: 00007f767df946c9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f767e1eafa8 RBP: 00007f767e1eafa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f767e1eb038 R14: 00007ffe1e18c080 R15: 00007ffe1e18c168