rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: 1-...!: (1 GPs behind) idle=0374/1/0x4000000000000000 softirq=105710/105711 fqs=691 (detected by 0, t=10502 jiffies, g=145593, q=125 ncpus=2) Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 9111 Comm: kworker/u4:21 Not tainted 6.1.76-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: netns cleanup_net RIP: 0010:do_raw_spin_unlock+0x0/0x8a0 kernel/locking/spinlock_debug.c:138 Code: f9 80 e1 07 80 c1 03 38 c1 0f 8c 2c ff ff ff e8 96 33 76 00 e9 22 ff ff ff e8 6c 9b 1e 09 66 2e 0f 1f 84 00 00 00 00 00 66 90 <55> 41 57 41 56 41 55 41 54 53 48 83 ec 28 49 89 ff 48 bb 00 00 00 RSP: 0018:ffffc900001e0c98 EFLAGS: 00000046 RAX: 6acb4093753afa00 RBX: ffffffff91f525f8 RCX: ffffc900001e0b03 RDX: 0000000000000005 RSI: ffffffff8aebfd40 RDI: ffffffff91f525f8 RBP: ffffc900001e0d28 R08: dffffc0000000000 R09: fffffbfff1ce6726 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 1ffff9200003c194 R14: ffffc900001e0cc0 R15: 0000000000000046 FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f613f3a8000 CR3: 000000007ced3000 CR4: 00000000003506e0 DR0: 00000000000009b2 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:150 [inline] _raw_spin_unlock_irqrestore+0x7d/0x130 kernel/locking/spinlock.c:194 debug_hrtimer_deactivate kernel/time/hrtimer.c:425 [inline] debug_deactivate+0x1d/0x280 kernel/time/hrtimer.c:481 __run_hrtimer kernel/time/hrtimer.c:1653 [inline] __hrtimer_run_queues+0x334/0xe50 kernel/time/hrtimer.c:1749 hrtimer_interrupt+0x392/0x980 kernel/time/hrtimer.c:1811 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1095 [inline] __sysvec_apic_timer_interrupt+0x156/0x580 arch/x86/kernel/apic/apic.c:1112 sysvec_apic_timer_interrupt+0x8c/0xb0 arch/x86/kernel/apic/apic.c:1106 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653 RIP: 0010:lock_acquire+0x26f/0x5a0 kernel/locking/lockdep.c:5666 Code: 2b 00 74 08 4c 89 f7 e8 9f 94 77 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:ffffc90011757900 EFLAGS: 00000206 RAX: 0000000000000001 RBX: 1ffff920022eaf2c RCX: 1ffff920022eaecc RDX: dffffc0000000000 RSI: ffffffff8aebfd40 RDI: ffffffff8b3d0780 RBP: ffffc90011757a48 R08: dffffc0000000000 R09: fffffbfff2092045 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920022eaf28 R13: dffffc0000000000 R14: ffffc90011757960 R15: 0000000000000246 rcu_lock_acquire include/linux/rcupdate.h:318 [inline] rcu_read_lock include/linux/rcupdate.h:759 [inline] inet_twsk_purge+0x164/0xb60 net/ipv4/inet_timewait_sock.c:295 ops_exit_list net/core/net_namespace.c:174 [inline] cleanup_net+0x763/0xb60 net/core/net_namespace.c:601 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: rcu_preempt kthread starved for 7045 jiffies! g145593 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:25624 pid:16 ppid:2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5245 [inline] __schedule+0x142d/0x4550 kernel/sched/core.c:6558 schedule+0xbf/0x180 kernel/sched/core.c:6634 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1935 rcu_gp_fqs_loop+0x2d2/0x1120 kernel/rcu/tree.c:1706 rcu_gp_kthread+0xa3/0x3a0 kernel/rcu/tree.c:1905 kthread+0x28d/0x320 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306 rcu: Stack dump where RCU GP kthread last ran: CPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.1.76-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 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:130 [inline] RIP: 0010:acpi_safe_halt drivers/acpi/processor_idle.c:113 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:572 Code: fa f5 f6 48 83 e3 08 0f 85 0b 01 00 00 4c 8d 74 24 20 e8 94 b5 fc f6 0f 1f 44 00 00 e8 3a f6 f5 f6 0f 00 2d 83 a5 b2 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 1b 5e 4d f7 RSP: 0018:ffffffff8ce07b20 EFLAGS: 000002d3 RAX: ffffffff8a947236 RBX: 0000000000000000 RCX: ffffffff8cebd800 RDX: 0000000000000000 RSI: ffffffff8aebebc0 RDI: ffffffff8b3d0780 RBP: ffffffff8ce07bb0 R08: ffffffff8a947218 R09: fffffbfff19d7b01 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffffffff19c0f64 R13: ffff8881462f9804 R14: ffffffff8ce07b40 R15: dffffc0000000000 FS: 0000000000000000(0000) GS:ffff8880b9800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007feb2692b6c0 CR3: 000000007c6d2000 CR4: 00000000003506f0 DR0: 00000000000009b2 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Call Trace: acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:709 cpuidle_enter_state+0x516/0xf80 drivers/cpuidle/cpuidle.c:239 cpuidle_enter+0x59/0x90 drivers/cpuidle/cpuidle.c:356 call_cpuidle kernel/sched/idle.c:155 [inline] cpuidle_idle_call kernel/sched/idle.c:236 [inline] do_idle+0x3ce/0x680 kernel/sched/idle.c:303 cpu_startup_entry+0x3d/0x60 kernel/sched/idle.c:401 rest_init+0x2da/0x300 init/main.c:731 arch_call_rest_init+0xa/0xa init/main.c:891 start_kernel+0x496/0x53f init/main.c:1138 secondary_startup_64_no_verify+0xcf/0xdb