rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P4478/1:b..l P3545/1:b..l P8442/1:b..l (detected by 1, t=10502 jiffies, g=36781, q=400) task:kworker/u4:25 state:R running task stack:23416 pid: 8442 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 irqentry_exit+0x53/0x80 kernel/entry/common.c:432 asm_sysvec_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:681 RIP: 0010:lock_acquire+0x252/0x4f0 kernel/locking/lockdep.c:5627 Code: 2b 00 74 08 4c 89 f7 e8 9c 9e 67 00 f6 44 24 61 02 0f 85 84 01 00 00 41 f7 c7 00 02 00 00 74 01 fb 48 c7 44 24 40 0e 36 e0 45 <4b> c7 44 25 00 00 00 00 00 43 c7 44 25 09 00 00 00 00 43 c7 44 25 RSP: 0018:ffffc9000364f8c0 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920006c9f24 RCX: 1ffff920006c9ec4 RDX: dffffc0000000000 RSI: ffffffff8aab3e20 RDI: ffffffff8af9f2c0 RBP: ffffc9000364fa20 R08: dffffc0000000000 R09: fffffbfff2131821 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920006c9f20 R13: dffffc0000000000 R14: ffffc9000364f920 R15: 0000000000000246 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] inet_twsk_purge+0x129/0x9d0 net/ipv4/inet_timewait_sock.c:268 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x886/0xc90 net/core/net_namespace.c:618 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:udevd state:R running task stack:22624 pid: 3545 ppid: 1 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_common+0x83/0xd0 kernel/sched/core.c:6549 preempt_schedule+0xd9/0xe0 kernel/sched/core.c:6574 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] __d_lookup+0x5be/0x730 fs/dcache.c:2446 lookup_fast+0xdc/0x7b0 fs/namei.c:1621 open_last_lookups fs/namei.c:3501 [inline] path_openat+0x6ae/0x2f20 fs/namei.c:3739 do_filp_open+0x21c/0x460 fs/namei.c:3769 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253 do_sys_open fs/open.c:1269 [inline] __do_sys_openat fs/open.c:1285 [inline] __se_sys_openat fs/open.c:1280 [inline] __x64_sys_openat+0x243/0x290 fs/open.c:1280 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f984c961477 RSP: 002b:00007fff351855c8 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 000055a366ee2c30 RCX: 00007f984c961477 RDX: 0000000000090800 RSI: 000055a366ee6ce0 RDI: 00000000ffffff9c RBP: 000055a366f867c0 R08: 0000000000090800 R09: 000055a366ee6ce0 R10: 0000000000000000 R11: 0000000000000287 R12: 000055a366ee6ce0 R13: 00000000000000ff R14: 000055a3513b61c4 R15: 0000000000000000 task:kworker/1:21 state:R running task stack:21304 pid: 4478 ppid: 2 flags:0x00004000 Workqueue: events_power_efficient gc_worker Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6777 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 c3 4f e5 f8 eb 15 e8 bc 4f e5 f8 e8 87 19 a4 01 4d 85 ed 74 ea e8 ad 4f e5 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:ffffc900030cfa40 EFLAGS: 00000293 RAX: ffffffff889b35e3 RBX: 0000000000000000 RCX: ffff88802c199dc0 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900030cfaf0 R08: ffffffff889b35b9 R09: fffffbfff2131834 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff92000619f48 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 rcu: rcu_preempt kthread starved for 10573 jiffies! g36781 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:27256 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5027 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6373 schedule+0x11b/0x1f0 kernel/sched/core.c:6456 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 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 10798 Comm: syz.5.1267 Not tainted 5.15.178-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __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:1688 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1752 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1814 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 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 61 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 0e 05 1a f7 48 89 df e8 66 59 1b f7 e8 b1 15 3e f7 fb bf 01 00 00 00 66 9e 0e f7 65 8b 05 77 81 b9 75 85 c0 74 02 5b c3 e8 44 9e b7 RSP: 0018:ffffc90002f3fbc0 EFLAGS: 00000282 RAX: daa93a9700e4e500 RBX: ffff8880678ec0c0 RCX: ffffffff96a92f03 RDX: dffffc0000000000 RSI: ffffffff8aab2b80 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff81870420 R09: ffffed100cf1d819 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021 R13: dffffc0000000000 R14: ffff8880678ec558 R15: ffff8880678ec0c0 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: 0033:0x7f7011154de7 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:00007f700efbe0e8 EFLAGS: 00000246 RAX: 00000000000000ca RBX: 00007f701136dfa8 RCX: 00007f7011154de9 RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f701136dfa8 RBP: 00007f701136dfa0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f701136dfac R13: 0000000000000000 R14: 00007ffe1d192d30 R15: 00007ffe1d192e18