rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P144/1:b..l P2962/1:b..l
	(detected by 1, t=10502 jiffies, g=10305, q=194)
task:udevd           state:R  running task     stack:24640 pid: 2962 ppid:     1 flags:0x00004002
Call Trace:
 <TASK>
 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:native_irq_enable arch/x86/include/asm/irqflags.h:45 [inline]
RIP: 0010:arch_local_irq_enable arch/x86/include/asm/irqflags.h:80 [inline]
RIP: 0010:arch_local_irq_restore arch/x86/include/asm/irqflags.h:140 [inline]
RIP: 0010:seqcount_lockdep_reader_access+0x1d2/0x220 include/linux/seqlock.h:105
Code: 5e e8 a2 d6 a6 ff 4d 85 f6 48 bb 00 00 00 00 00 fc ff df 75 07 e8 8e d6 a6 ff eb 06 e8 87 d6 a6 ff fb 48 c7 04 24 0e 36 e0 45 <4a> c7 04 23 00 00 00 00 66 42 c7 44 23 09 00 00 42 c6 44 23 0b 00
RSP: 0018:ffffc90002c475a0 EFLAGS: 00000293
RAX: ffffffff81d98449 RBX: dffffc0000000000 RCX: ffff88807d413b80
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90002c47650 R08: ffffffff81d98424 R09: fffffbfff1bc8d86
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000588eb4
R13: ffffc90002c475c0 R14: 0000000000000200 R15: 0000000000000046
 __follow_mount_rcu fs/namei.c:1457 [inline]
 handle_mounts fs/namei.c:1490 [inline]
 step_into+0x756/0xe90 fs/namei.c:1806
 walk_component+0x359/0x610 fs/namei.c:1982
 link_path_walk+0x642/0xd90
 path_lookupat+0xa9/0x450 fs/namei.c:2454
 filename_lookup+0x230/0x5c0 fs/namei.c:2484
 user_path_at_empty+0x40/0x180 fs/namei.c:2883
 user_path_at include/linux/namei.h:57 [inline]
 vfs_statx+0x106/0x3b0 fs/stat.c:221
 vfs_fstatat fs/stat.c:243 [inline]
 __do_sys_newfstatat fs/stat.c:411 [inline]
 __se_sys_newfstatat fs/stat.c:405 [inline]
 __x64_sys_newfstatat+0x12c/0x1b0 fs/stat.c:405
 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: 0033:0x7f9d91c9a5f4
RSP: 002b:00007ffe9a16a8e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000106
RAX: ffffffffffffffda RBX: 0000555644a532c0 RCX: 00007f9d91c9a5f4
RDX: 00007ffe9a16a8f8 RSI: 00007ffe9a16ad88 RDI: 00000000ffffff9c
RBP: 00007ffe9a16a988 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe9a16ad88
R13: 00007ffe9a16a8f8 R14: 0000555644a52910 R15: 0000000000000000
 </TASK>
task:kworker/u4:1    state:R  running task     stack:21088 pid:  144 ppid:     2 flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 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_reschedule_ipi+0x16/0x20 arch/x86/include/asm/idtentry.h:643
RIP: 0010:debug_lockdep_rcu_enabled+0x25/0x30 kernel/rcu/update.c:281
Code: cc cc cc cc cc 31 c0 83 3d 2b 2a c6 03 00 74 1d 83 3d a2 5c c6 03 00 74 14 65 48 8b 0d 94 2c e4 75 31 c0 83 b9 ec 0a 00 00 00 <0f> 94 c0 c3 cc cc cc cc cc cc cc 41 56 53 89 fb e8 d6 0d 00 00 41
RSP: 0018:ffffc9000147fa58 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 000000000000b466 RCX: ffff8880143c5940
RDX: dffffc0000000000 RSI: ffffffff8a8b3ca0 RDI: ffffffff8ad8f740
RBP: ffffc9000147fb70 R08: dffffc0000000000 R09: fffffbfff1f7f219
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff9200028ff62
R13: 000000000000b465 R14: dffffc0000000000 R15: ffffc900016c5330
 rcu_read_lock include/linux/rcupdate.h:740 [inline]
 inet_twsk_purge+0x12e/0x9d0 net/ipv4/inet_timewait_sock.c:268
 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>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10349 jiffies! g10305 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=3525
rcu: rcu_preempt kthread starved for 10350 jiffies! g10305 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->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:I stack:27064 pid:   15 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 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
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:109 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:570