rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P6861/1:b..l (detected by 0, t=10502 jiffies, g=24113, q=52) task:kworker/u4:17 state:R running task stack:24800 pid: 6861 ppid: 2 flags:0x00004000 Workqueue: netns cleanup_net Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 preempt_schedule_common+0x82/0xd0 kernel/sched/core.c:6552 preempt_schedule+0xa7/0xb0 kernel/sched/core.c:6577 preempt_schedule_thunk+0x16/0x18 arch/x86/entry/thunk_64.S:34 __local_bh_enable_ip+0x13b/0x1b0 kernel/softirq.c:390 spin_unlock_bh include/linux/spinlock.h:408 [inline] sctp_inet6addr_event+0x67d/0x730 net/sctp/ipv6.c:113 notifier_call_chain kernel/notifier.c:83 [inline] atomic_notifier_call_chain+0x15d/0x280 kernel/notifier.c:198 addrconf_ifdown+0xdf4/0x1970 net/ipv6/addrconf.c:3903 addrconf_notify+0x445/0xf00 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] dev_close_many+0x28d/0x400 net/core/dev.c:1650 unregister_netdevice_many+0x472/0x18f0 net/core/dev.c:11110 default_device_exit_batch+0x336/0x390 net/core/dev.c:11667 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x77b/0xb80 net/core/net_namespace.c:635 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 rcu: rcu_preempt kthread starved for 10528 jiffies! g24113 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:28032 pid: 15 ppid: 2 flags:0x00004000 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 schedule_timeout+0x15c/0x280 kernel/time/timer.c:1914 rcu_gp_fqs_loop+0x29e/0x11b0 kernel/rcu/tree.c:1972 rcu_gp_kthread+0x98/0x350 kernel/rcu/tree.c:2145 kthread+0x436/0x520 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: Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 7865 Comm: syz.0.823 Not tainted 5.15.181-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:arch_static_branch arch/x86/include/asm/jump_label.h:27 [inline] RIP: 0010:static_key_false include/linux/jump_label.h:212 [inline] RIP: 0010:native_write_msr arch/x86/include/asm/msr.h:156 [inline] RIP: 0010:wrmsr arch/x86/include/asm/msr.h:263 [inline] RIP: 0010:native_apic_msr_write+0x35/0x50 arch/x86/include/asm/apic.h:208 Code: 74 2a 83 ff 30 74 25 eb 10 81 ff d0 00 00 00 74 1b 81 ff e0 00 00 00 74 13 c1 ef 04 81 c7 00 08 00 00 89 f9 89 f0 31 d2 0f 30 <66> 90 c3 89 f6 31 d2 e9 1f 30 c8 02 66 2e 0f 1f 84 00 00 00 00 00 RSP: 0018:ffffc90000dd0e48 EFLAGS: 00000046 RAX: 000000000003dfc2 RBX: 000000000003dfc2 RCX: 0000000000000838 RDX: 0000000000000000 RSI: 000000000003dfc2 RDI: 0000000000000838 RBP: 0000000000000000 R08: dffffc0000000000 R09: fffffbfff1ad155e R10: fffffbfff1ad155e R11: 1ffffffff1ad155d R12: dffffc0000000000 R13: 0000000010005c46 R14: ffffffff8bbae9c8 R15: dffffc0000000000 FS: 000055557cb8f500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000562444b3fbf8 CR3: 000000006a6be000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: apic_write arch/x86/include/asm/apic.h:395 [inline] lapic_next_event+0x5b/0x70 arch/x86/kernel/apic/apic.c:468 clockevents_program_event+0x1bc/0x310 kernel/time/clockevents.c:334 hrtimer_interrupt+0x4de/0x8d0 kernel/time/hrtimer.c:1829 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1097 [inline] __sysvec_apic_timer_interrupt+0x137/0x4a0 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: f6 ff 0f 1f 00 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 4e d6 b1 f7 48 89 df e8 16 ab b2 f7 e8 71 4f d3 f7 fb bf 01 00 00 00 46 cf a6 f7 65 8b 05 e7 e2 57 76 85 c0 74 02 5b c3 e8 94 ed 55 RSP: 0018:ffffc9000418fbc0 EFLAGS: 00000282 RAX: 850f6cffa2a70600 RBX: ffff8880758b3780 RCX: 850f6cffa2a70600 RDX: dffffc0000000000 RSI: ffffffff8a0b0fc0 RDI: 0000000000000001 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffffed100eb166f1 R10: ffffed100eb166f1 R11: 1ffff1100eb166f0 R12: ffff8880758b3780 R13: 0000000000000021 R14: dffffc0000000000 R15: 000000001c000004 spin_unlock_irq include/linux/spinlock.h:413 [inline] get_signal+0x11d6/0x12c0 kernel/signal.c:2903 arch_do_signal_or_restart+0xc1/0x1300 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0x9e/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+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa865707830 Code: ef fe ff ff 48 8d 3d 02 ad 1b 00 31 c0 e8 48 82 ff ff 48 8d 3d db ae 1b 00 31 c0 e8 3a 82 ff ff 66 2e 0f 1f 84 00 00 00 00 00 <41> 57 41 56 41 55 41 54 55 53 48 83 ec 18 48 8b 47 38 48 8b 57 40 RSP: 002b:00007ffec35c9938 EFLAGS: 00010246 RAX: 0000000000002008 RBX: 00007fa866596720 RCX: 0000000000000000 RDX: 0000000000000031 RSI: 0000000000000008 RDI: 00007fa866596720 RBP: 00000000000000fc R08: 00007fa864eb00a8 R09: 00007fa865a53000 R10: 00007fa864eb0008 R11: 0000000000000005 R12: ffffffff814a19fa R13: 00007fa865a67038 R14: 00000000000000cb R15: ffffffffffffdff8