rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6109/1:b..l P3622/1:b..l (detected by 1, t=10502 jiffies, g=26633, q=342) task:kworker/u4:5 state:R running task stack:23040 pid: 3622 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_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:inet_twsk_purge+0x1bc/0x9d0 net/ipv4/inet_timewait_sock.c:270 Code: be e5 02 00 00 48 c7 c2 c0 31 87 8b e8 fd 36 90 f8 4c 89 f8 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 d7 57 f7 f8 4d 8b 2f <4c> 89 ee 48 83 e6 01 31 ff e8 d6 92 ad f8 4c 89 e8 48 83 e0 01 0f RSP: 0018:ffffc90003107a60 EFLAGS: 00000246 RAX: 1ffff110048856b0 RBX: 0000000000000001 RCX: ffff88802253bb80 RDX: 0000000000000000 RSI: ffffffff8ad8f7a0 RDI: ffffffff8ad8f760 RBP: ffffc90003107b70 R08: ffffffff88d2d219 R09: fffffbfff1f8e219 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000620f62 R13: 000000000000ad61 R14: dffffc0000000000 R15: ffff88802442b580 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x763/0xb60 net/core/net_namespace.c:599 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:modprobe state:R running task stack:26040 pid: 6109 ppid: 3925 flags:0x00004000 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:638 RIP: 0010:seqcount_lockdep_reader_access+0x1dc/0x220 include/linux/seqlock.h:106 Code: 00 4d 85 ed 75 16 e8 f3 b2 10 00 eb 15 e8 ec b2 10 00 e8 b7 9e c3 08 4d 85 ed 74 ea e8 dd b2 10 00 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:ffffc900033a7300 EFLAGS: 00000293 RAX: ffffffff816faec3 RBX: 0000000000000000 RCX: ffff88801bc9bb80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc900033a73a8 R08: ffffffff816fae99 R09: fffffbfff1bd2a56 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000200 R14: 0000000000000046 R15: 1ffff92000674e60 ktime_get_coarse_real_ts64+0x36/0x120 kernel/time/timekeeping.c:2244 current_time+0x87/0x300 fs/inode.c:2327 atime_needs_update+0x3fa/0x7b0 fs/inode.c:1867 pick_link+0x465/0xce0 fs/namei.c:1754 step_into+0xbae/0xe90 fs/namei.c:1832 walk_component+0x359/0x610 fs/namei.c:1982 link_path_walk+0x642/0xd90 path_openat+0x249/0x2f20 fs/namei.c:3738 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: 0033:0x7f337f37da46 RSP: 002b:00007ffc0d1e7fe8 EFLAGS: 00000287 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007ffc0d1e8248 RCX: 00007f337f37da46 RDX: 0000000000080000 RSI: 00007ffc0d1e8060 RDI: 00000000ffffff9c RBP: 00007ffc0d1e8050 R08: 0000000000080000 R09: 00007ffc0d1e8060 R10: 0000000000000000 R11: 0000000000000287 R12: 00007ffc0d1e8060 R13: 0000000000000009 R14: 00007ffc0d1e822f R15: 00000000ffffffff rcu: rcu_preempt kthread starved for 9816 jiffies! g26633 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:26144 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: 0 Comm: swapper/1 Not tainted 5.15.165-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 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:1686 [inline] __hrtimer_run_queues+0x55b/0xcf0 kernel/time/hrtimer.c:1750 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1812 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1085 [inline] __sysvec_apic_timer_interrupt+0x139/0x470 arch/x86/kernel/apic/apic.c:1102 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1096 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:638 RIP: 0010:native_save_fl arch/x86/include/asm/irqflags.h:22 [inline] RIP: 0010:arch_local_save_flags arch/x86/include/asm/irqflags.h:70 [inline] RIP: 0010:arch_irqs_disabled arch/x86/include/asm/irqflags.h:132 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:562 Code: 8a 43 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 24 07 4a f7 0f 1f 44 00 00 e8 8a 86 43 f7 0f 00 2d c3 50 a6 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 bb 4f 8d f7 RSP: 0018:ffffc90000d67b00 EFLAGS: 000002d3 RAX: ffffffff8a3cdb16 RBX: 0000000000000000 RCX: ffff888012a18000 RDX: 0000000000000000 RSI: ffffffff8a8b2a20 RDI: ffffffff8ad8f7c0 RBP: ffffc90000d67b90 R08: ffffffff8186e260 R09: ffffed1002543001 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001acf60 R13: ffff888146641004 R14: ffffc90000d67b20 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:697 cpuidle_enter_state+0x521/0xef0 drivers/cpuidle/cpuidle.c:237 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:351 call_cpuidle kernel/sched/idle.c:158 [inline] cpuidle_idle_call kernel/sched/idle.c:239 [inline] do_idle+0x3e4/0x670 kernel/sched/idle.c:306 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:403 start_secondary+0x371/0x500 arch/x86/kernel/smpboot.c:281 secondary_startup_64_no_verify+0xb1/0xbb