rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P3863/1:b..l (detected by 0, t=10503 jiffies, g=8557, q=132) task:kworker/u4:15 state:R running task stack:23768 pid: 3863 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:inet_twsk_purge+0x1bc/0x9d0 net/ipv4/inet_timewait_sock.c:270 Code: be e5 02 00 00 48 c7 c2 40 29 87 8b e8 fd 66 90 f8 4c 89 f8 48 c1 e8 03 42 80 3c 30 00 74 08 4c 89 ff e8 57 93 f7 f8 4d 8b 2f <4c> 89 ee 48 83 e6 01 31 ff e8 46 c3 ad f8 4c 89 e8 48 83 e0 01 0f RSP: 0000:ffffc90003167a60 EFLAGS: 00000246 RAX: 1ffff11029612858 RBX: 0000000000000001 RCX: ffff888022da5940 RDX: 0000000000000000 RSI: ffffffff8ad8f7e0 RDI: ffffffff8ad8f7a0 RBP: ffffc90003167b70 R08: ffffffff88d2a169 R09: fffffbfff1f8e019 R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200062cf62 R13: 00000000000250b1 R14: dffffc0000000000 R15: ffff88814b0942c0 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 rcu: rcu_preempt kthread starved for 10514 jiffies! g8557 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:26816 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: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: 4133 Comm: syz.0.66 Not tainted 5.15.164-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024 RIP: 0010:get_current arch/x86/include/asm/current.h:15 [inline] RIP: 0010:__sanitizer_cov_trace_pc+0x4/0x60 kernel/kcov.c:196 Code: 00 00 00 0f 1f 00 53 48 89 fb e8 17 00 00 00 48 8b 3d 08 ed 68 0c 48 89 de 5b e9 c7 fc 48 00 cc cc cc cc cc cc cc 48 8b 04 24 <65> 48 8b 0d 54 0e 82 7e 65 8b 15 55 0e 82 7e f7 c2 00 01 ff 00 74 RSP: 0018:ffffc90000dd0d98 EFLAGS: 00000046 RAX: ffffffff816faf93 RBX: 0000000000000000 RCX: ffff88807b5a8000 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000dd0e48 R08: ffffffff816faf89 R09: fffffbfff1bd2986 R10: 0000000000000000 R11: dffffc0000000001 R12: dffffc0000000000 R13: 0000000000000000 R14: 0000000000000046 R15: 1ffff920001ba1b4 FS: 00007f13cd5046c0(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002006b000 CR3: 000000007cb82000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: seqcount_lockdep_reader_access+0x1b3/0x220 include/linux/seqlock.h:105 timekeeping_get_delta kernel/time/timekeeping.c:254 [inline] timekeeping_get_ns kernel/time/timekeeping.c:388 [inline] ktime_get_update_offsets_now+0x89/0x420 kernel/time/timekeeping.c:2303 hrtimer_update_base kernel/time/hrtimer.c:631 [inline] hrtimer_interrupt+0x12f/0x980 kernel/time/hrtimer.c:1794 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:__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: a1 68 f6 ff 90 53 48 89 fb 48 83 c7 18 48 8b 74 24 08 e8 8e 2d 26 f7 48 89 df e8 66 81 27 f7 e8 f1 3c 4a f7 fb bf 01 00 00 00 16 c6 1a f7 65 8b 05 d7 ca c5 75 85 c0 74 02 5b c3 e8 a4 e7 c3 RSP: 0018:ffffc90002067bc0 EFLAGS: 00000282 RAX: edeccc9b50e8ee00 RBX: ffff88807a8aef00 RCX: ffffffff91467f03 RDX: dffffc0000000000 RSI: ffffffff8a8b2a00 RDI: 0000000000000001 RBP: 0000000000000000 R08: ffffffff8186e200 R09: ffffed100f515de1 R10: 0000000000000000 R11: dffffc0000000001 R12: 0000000000000021 R13: dffffc0000000000 R14: ffff88807a8af398 R15: ffff88807a8aef00 spin_unlock_irq include/linux/spinlock.h:413 [inline] get_signal+0x13ee/0x14e0 kernel/signal.c:2892 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: 0033:0x7f13cf0859f7 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:00007f13cd504048 EFLAGS: 00000246 RAX: 0000000000000113 RBX: 00007f13cf213f80 RCX: 00007f13cf0859f9 RDX: 0000000000000008 RSI: 0000000000000000 RDI: 0000000000000006 RBP: 00007f13cf0f38ee R08: 0000000008000f28 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f13cf213f80 R15: 00007ffc42b4be18 sched: RT throttling activated