rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P17740/1:b..l P11460/1:b..l (detected by 1, t=10502 jiffies, g=93801, q=35) task:kworker/u4:11 state:R running task stack:21120 pid:11460 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: 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:638 RIP: 0010:rcu_read_lock include/linux/rcupdate.h:740 [inline] RIP: 0010:inet_twsk_purge+0x13d/0x9d0 net/ipv4/inet_timewait_sock.c:268 Code: 31 d2 e8 f6 4f 9b f8 2e 2e 2e 31 c0 e8 dc f6 ad f8 e8 e7 08 00 00 e8 02 24 60 01 89 c3 31 ff 89 c6 e8 c7 90 c2 f8 85 db 74 10 ee 44 ad f8 84 c0 74 0e e8 55 8d c2 f8 eb 56 e8 4e 8d c2 f8 eb RSP: 0018:ffffc900032a7a60 EFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffff88801bdc1dc0 RDX: ffff88801bdc1dc0 RSI: 0000000000000001 RDI: 0000000000000000 RBP: ffffc900032a7b70 R08: ffffffff88bdcf59 R09: fffffbfff1f7f019 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000654f62 R13: 0000000000016dac R14: dffffc0000000000 R15: ffff8880244b6d68 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:300 task:syz-executor.4 state:R running task stack:20504 pid:17740 ppid: 17730 flags:0x00004002 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x12c4/0x45b0 kernel/sched/core.c:6376 preempt_schedule_notrace+0xf8/0x140 kernel/sched/core.c:6631 preempt_schedule_notrace_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:35 rcu_is_watching+0x72/0xa0 kernel/rcu/tree.c:1124 trace_lock_acquire include/trace/events/lock.h:13 [inline] lock_acquire+0xdd/0x4f0 kernel/locking/lockdep.c:5594 rcu_lock_acquire+0x2a/0x30 include/linux/rcupdate.h:312 rcu_read_lock include/linux/rcupdate.h:739 [inline] veth_get_iflink+0x1d/0x230 drivers/net/veth.c:1370 linkwatch_urgent_event+0x93/0x4b0 net/core/link_watch.c:95 linkwatch_fire_event+0x1b/0x3c0 net/core/link_watch.c:259 netif_carrier_on+0xa5/0x130 net/sched/sch_generic.c:529 veth_open+0x1e3/0x220 drivers/net/veth.c:1273 __dev_open+0x36f/0x500 net/core/dev.c:1506 __dev_change_flags+0x1db/0x6e0 net/core/dev.c:8813 dev_change_flags+0x87/0x190 net/core/dev.c:8884 do_setlink+0xcd1/0x3b00 net/core/rtnetlink.c:2741 __rtnl_newlink net/core/rtnetlink.c:3429 [inline] rtnl_newlink+0x17a4/0x2070 net/core/rtnetlink.c:3549 rtnetlink_rcv_msg+0x993/0xee0 net/core/rtnetlink.c:5629 netlink_rcv_skb+0x1cf/0x410 net/netlink/af_netlink.c:2508 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x7b6/0x980 net/netlink/af_netlink.c:1356 netlink_sendmsg+0xa30/0xd60 net/netlink/af_netlink.c:1924 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x564/0x720 net/socket.c:2058 __do_sys_sendto net/socket.c:2070 [inline] __se_sys_sendto net/socket.c:2066 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2066 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: 0033:0x7f85067fab9c RSP: 002b:00007ffc7bc614b0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f8507460620 RCX: 00007f85067fab9c RDX: 000000000000002c RSI: 00007f8507460670 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007ffc7bc61504 R09: 000000000000000c R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003 R13: 0000000000000000 R14: 00007f8507460670 R15: 0000000000000000 rcu: rcu_preempt kthread starved for 10573 jiffies! g93801 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:27000 pid: 15 ppid: 2 flags:0x00004000 Call Trace: 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:300 rcu: Stack dump where RCU GP kthread last ran: NMI backtrace for cpu 1 CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.15.160-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 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:110 [inline] RIP: 0010:acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570 Code: fd 58 f7 48 83 e3 08 0f 85 0a 01 00 00 4c 8d 74 24 20 e8 24 79 5f f7 0f 1f 44 00 00 e8 1a f9 58 f7 0f 00 2d 33 bb bb 00 fb f4 <4c> 89 f3 48 c1 eb 03 42 80 3c 3b 00 74 08 4c 89 f7 e8 8b c7 a2 f7 RSP: 0018:ffffc90000d67b00 EFLAGS: 000002d3 RAX: ffffffff8a2763a6 RBX: 0000000000000000 RCX: ffff88813fe78000 RDX: 0000000000000000 RSI: ffffffff8a8b2980 RDI: ffffffff8ad8f6c0 RBP: ffffc90000d67b90 R08: ffffffff8186dcf0 R09: ffffed1027fcf001 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920001acf60 R13: ffff8881463ce804 R14: ffffc90000d67b20 R15: dffffc0000000000 acpi_idle_enter+0x352/0x4f0 drivers/acpi/processor_idle.c:705 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