rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P5762/1:b..l
	(detected by 0, t=10502 jiffies, g=19169, q=300)
task:kworker/0:21    state:R  running task     stack:25088 pid: 5762 ppid:     2 flags:0x00004000
Workqueue: events_power_efficient gc_worker
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6780
 irqentry_exit+0x53/0x80 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+0x1dc/0x220 include/linux/seqlock.h:106
Code: f8 4d 85 ed 75 16 e8 33 ac e4 f8 eb 15 e8 2c ac e4 f8 e8 97 2d a4 01 4d 85 ed 74 ea e8 1d ac e4 f8 fb 48 c7 04 24 0e 36 e0 45 <4b> c7 04 3c 00 00 00 00 66 43 c7 44 3c 09 00 00 43 c6 44 3c 0b 00
RSP: 0018:ffffc9000350fa40 EFLAGS: 00000293
RAX: ffffffff889bf1c3 RBX: 0000000000000000 RCX: ffff888028f00000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000350faf0 R08: ffffffff889bf199 R09: fffffbfff213222c
R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000
R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff920006a1f48
 nf_conntrack_get_ht include/net/netfilter/nf_conntrack.h:338 [inline]
 gc_worker+0x30f/0x14b0 net/netfilter/nf_conntrack_core.c:1472
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: rcu_preempt kthread starved for 10464 jiffies! g19169 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:26584 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5030 [inline]
 __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376
 schedule+0x11b/0x1f0 kernel/sched/core.c:6459
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1914
 rcu_gp_fqs_loop+0x2bf/0x1080 kernel/rcu/tree.c:1972
 rcu_gp_kthread+0xa4/0x360 kernel/rcu/tree.c:2145
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
NMI backtrace for cpu 0
CPU: 0 PID: 6048 Comm: syz.2.305 Not tainted 5.15.180-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x46a/0x4a0 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x181/0x2a0 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:166 [inline]
 rcu_check_gp_kthread_starvation+0x1d2/0x240 kernel/rcu/tree_stall.h:487
 print_other_cpu_stall+0x137a/0x14d0 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+0xa38/0x1150 kernel/rcu/tree.c:2619
 update_process_times+0x196/0x200 kernel/time/timer.c:1818
 tick_sched_handle kernel/time/tick-sched.c:254 [inline]
 tick_sched_timer+0x386/0x550 kernel/time/tick-sched.c:1473
 __run_hrtimer kernel/time/hrtimer.c:1690 [inline]
 __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1754
 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1816
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline]
 __sysvec_apic_timer_interrupt+0x13b/0x4b0 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
 </IRQ>
 <TASK>
 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: 31 60 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 ee 48 19 f7 48 89 df e8 46 9d 1a f7 e8 31 5d 3d f7 fb bf 01 00 00 00 <e8> 16 e0 0d f7 65 8b 05 87 b0 b8 75 85 c0 74 02 5b c3 e8 54 cd b6
RSP: 0018:ffffc900031efbc0 EFLAGS: 00000282
RAX: 041023afb43cab00 RBX: ffff8880759165c0 RCX: ffffffff96a97f03
RDX: dffffc0000000000 RSI: ffffffff8aab2b60 RDI: 0000000000000001
RBP: 0000000000000000 R08: ffffffff81871c90 R09: ffffed100eb22cb9
R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021
R13: dffffc0000000000 R14: ffff888075916a58 R15: ffff8880759165c0
 spin_unlock_irq include/linux/spinlock.h:413 [inline]
 get_signal+0x13ee/0x14e0 kernel/signal.c:2903
 arch_do_signal_or_restart+0xc3/0x1890 arch/x86/kernel/signal.c:867
 handle_signal_work kernel/entry/common.c:154 [inline]
 exit_to_user_mode_loop+0x97/0x130 kernel/entry/common.c:178
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fc849e1f7e4
Code: ac 24 c8 00 00 00 48 89 ef e8 78 dc fe ff 48 89 ef 48 89 c3 e8 6d dc fe ff 48 89 de 49 89 d9 49 89 d8 48 c1 ee 20 49 c1 e9 18 <48> 8b 7c 24 68 0f b6 cf 48 0f af 35 94 1e e7 00 49 c1 e8 10 0f b6
RSP: 002b:00007ffdefad43e0 EFLAGS: 00000206
RAX: 0000000000000005 RBX: 0000000003000001 RCX: fffffffffffffffa
RDX: 0000000000000005 RSI: 0000000000000000 RDI: 00007ffdefad44a8
RBP: 00007ffdefad44a8 R08: 0000000003000001 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000002
R13: 00007ffdefad44d0 R14: fffffffffffffffe R15: 00007ffdefad44f0
 </TASK>
sched: RT throttling activated