rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=1fac/1/0x4000000000000000 softirq=7206/7225 fqs=3 rcu: (detected by 0, t=10502 jiffies, g=7829, q=321 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 25 Comm: kworker/1:0 Not tainted 6.9.0-syzkaller-12393-g9b62e02e6336 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: events_power_efficient gc_worker RIP: 0010:mark_lock+0x92/0xc60 kernel/locking/lockdep.c:4647 Code: 00 f3 c7 40 14 f3 f3 f3 f3 65 48 8b 04 25 28 00 00 00 48 89 84 24 08 01 00 00 31 c0 41 83 fe 09 0f 87 e3 00 00 00 41 83 fe 08 <49> 89 fc 48 89 f3 0f 84 97 00 00 00 41 bd 01 00 00 00 44 89 f1 41 RSP: 0018:ffffc90000a18950 EFLAGS: 00000093 RAX: 0000000000000000 RBX: ffff888017ea29a2 RCX: 0000000000000002 RDX: dffffc0000000000 RSI: ffff888017ea2980 RDI: ffff888017ea1e00 RBP: ffffc90000a18a88 R08: 0000000000000000 R09: 0000000000000001 R10: ffffffff9426b2cf R11: 0000000000000004 R12: ffffed1002fd451b R13: ffff888017ea28e0 R14: 0000000000000000 R15: 1ffff92000143130 FS: 0000000000000000(0000) GS:ffff8880b9300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f245007e2d0 CR3: 000000002e4c0000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: mark_usage kernel/locking/lockdep.c:4564 [inline] __lock_acquire+0x1359/0x3b30 kernel/locking/lockdep.c:5091 lock_acquire kernel/locking/lockdep.c:5754 [inline] lock_acquire+0x1b1/0x560 kernel/locking/lockdep.c:5719 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline] _raw_spin_lock_irqsave+0x3a/0x60 kernel/locking/spinlock.c:162 debug_object_activate+0x199/0x540 lib/debugobjects.c:708 debug_hrtimer_activate kernel/time/hrtimer.c:423 [inline] debug_activate kernel/time/hrtimer.c:478 [inline] enqueue_hrtimer+0x25/0x3c0 kernel/time/hrtimer.c:1085 __run_hrtimer kernel/time/hrtimer.c:1704 [inline] __hrtimer_run_queues+0xaac/0xcc0 kernel/time/hrtimer.c:1751 hrtimer_interrupt+0x31b/0x800 kernel/time/hrtimer.c:1813 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1032 [inline] __sysvec_apic_timer_interrupt+0x10f/0x450 arch/x86/kernel/apic/apic.c:1049 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline] sysvec_apic_timer_interrupt+0x90/0xb0 arch/x86/kernel/apic/apic.c:1043 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702 RIP: 0010:__seqprop_spinlock_sequence include/linux/seqlock.h:227 [inline] RIP: 0010:nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:345 [inline] RIP: 0010:gc_worker+0x2e1/0x1770 net/netfilter/nf_conntrack_core.c:1488 Code: 00 00 48 c7 c7 88 05 e5 8f e8 2b e8 61 f8 9c 5b 81 e3 00 02 00 00 31 ff 48 89 de e8 a9 fd 83 f8 48 85 db 58 0f 85 3d 10 00 00 6a 02 84 f8 eb 07 e8 63 02 84 f8 f3 90 44 8b 35 ea 32 db 06 31 RSP: 0018:ffffc900001f7bc8 EFLAGS: 00000293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff8909de51 RDX: ffff888017ea1e00 RSI: ffffffff8909de60 RDI: 0000000000000007 RBP: ffff88801e000000 R08: 0000000000000007 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000003 R12: 00000000000087a1 R13: dffffc0000000000 R14: 0000000000010f41 R15: 0000000000040000 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.076 msecs rcu: rcu_preempt kthread starved for 10489 jiffies! g7829 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:27584 pid:17 tgid:17 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5408 [inline] __schedule+0xf15/0x5d00 kernel/sched/core.c:6745 __schedule_loop kernel/sched/core.c:6822 [inline] schedule+0xe7/0x350 kernel/sched/core.c:6837 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2000 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2202 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 11 Comm: kworker/u8:0 Not tainted 6.9.0-syzkaller-12393-g9b62e02e6336 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024 Workqueue: events_unbound toggle_allocation_gate RIP: 0010:csd_lock_wait kernel/smp.c:311 [inline] RIP: 0010:smp_call_function_many_cond+0x4e7/0x1420 kernel/smp.c:855 Code: 0c 00 85 ed 74 4d 48 b8 00 00 00 00 00 fc ff df 4d 89 f4 4c 89 f5 49 c1 ec 03 83 e5 07 49 01 c4 83 c5 03 e8 bb 37 0c 00 f3 90 <41> 0f b6 04 24 40 38 c5 7c 08 84 c0 0f 85 f7 0c 00 00 8b 43 08 31 RSP: 0018:ffffc90000107908 EFLAGS: 00000293 RAX: 0000000000000000 RBX: ffff8880b9344980 RCX: ffffffff81819d5b RDX: ffff8880176b3c00 RSI: ffffffff81819d35 RDI: 0000000000000005 RBP: 0000000000000003 R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000006 R12: ffffed1017268931 R13: 0000000000000001 R14: ffff8880b9344988 R15: ffff8880b923fdc0 FS: 0000000000000000(0000) GS:ffff8880b9200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000600 CR3: 000000000d97a000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: on_each_cpu_cond_mask+0x40/0x90 kernel/smp.c:1023 on_each_cpu include/linux/smp.h:71 [inline] text_poke_sync arch/x86/kernel/alternative.c:2069 [inline] text_poke_bp_batch+0x22b/0x760 arch/x86/kernel/alternative.c:2279 text_poke_flush arch/x86/kernel/alternative.c:2470 [inline] text_poke_flush arch/x86/kernel/alternative.c:2467 [inline] text_poke_finish+0x30/0x40 arch/x86/kernel/alternative.c:2477 arch_jump_label_transform_apply+0x1c/0x30 arch/x86/kernel/jump_label.c:146 jump_label_update+0x1d7/0x400 kernel/jump_label.c:882 static_key_enable_cpuslocked+0x1b7/0x270 kernel/jump_label.c:205 static_key_enable+0x1a/0x20 kernel/jump_label.c:218 toggle_allocation_gate mm/kfence/core.c:826 [inline] toggle_allocation_gate+0xf8/0x250 mm/kfence/core.c:818 process_one_work+0x9fb/0x1b60 kernel/workqueue.c:3231 process_scheduled_works kernel/workqueue.c:3312 [inline] worker_thread+0x6c8/0xf70 kernel/workqueue.c:3393 kthread+0x2c1/0x3a0 kernel/kthread.c:389 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244