rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4675/1:b..l P78/1:b..l
rcu: 	(detected by 1, t=10502 jiffies, g=26945, q=857 ncpus=2)
task:kworker/u8:5    state:R  running task     stack:25392 pid:78    tgid:78    ppid:2      flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 preempt_schedule_common+0x44/0xc0 kernel/sched/core.c:6708
 preempt_schedule_thunk+0x1a/0x30 arch/x86/entry/thunk.S:12
 ___slab_alloc+0x10ad/0x1870 mm/slub.c:3726
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3817
 __slab_alloc_node mm/slub.c:3870 [inline]
 slab_alloc_node mm/slub.c:4029 [inline]
 kmem_cache_alloc_noprof+0x2a7/0x2f0 mm/slub.c:4048
 dst_alloc+0x99/0x1a0 net/core/dst.c:89
 ip6_dst_alloc+0x2c/0x90 net/ipv6/route.c:342
 icmp6_dst_alloc+0x70/0x490 net/ipv6/route.c:3275
 mld_sendpack+0x5a9/0x11d0 net/ipv6/mcast.c:1807
 mld_send_initial_cr.part.0+0x1a1/0x260 net/ipv6/mcast.c:2236
 mld_send_initial_cr include/linux/refcount.h:192 [inline]
 ipv6_mc_dad_complete+0x22c/0x2b0 net/ipv6/mcast.c:2244
 addrconf_dad_completed+0xd42/0x1060 net/ipv6/addrconf.c:4340
 addrconf_dad_work+0x7fb/0x14d0 net/ipv6/addrconf.c:4268
 process_one_work+0x9c5/0x1b40 kernel/workqueue.c:3231
 process_scheduled_works kernel/workqueue.c:3312 [inline]
 worker_thread+0x6c8/0xed0 kernel/workqueue.c:3389
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>
task:udevd           state:R  running task     stack:22736 pid:4675  tgid:4675  ppid:1      flags:0x00000002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 preempt_schedule_irq+0x51/0x90 kernel/sched/core.c:6851
 irqentry_exit+0x36/0x90 kernel/entry/common.c:354
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
RIP: 0010:rcu_read_lock include/linux/rcupdate.h:839 [inline]
RIP: 0010:dput.part.0+0x5e/0x9b0 fs/dcache.c:850
Code: 02 00 00 00 48 c7 c7 e0 9f db 8d 48 8d 05 00 00 00 00 50 e8 c4 18 67 ff e8 6f 36 14 09 31 ff 89 c5 89 c6 e8 a4 1b 89 ff 85 ed <5a> 0f 85 6f 02 00 00 e8 56 19 89 ff 4c 8d a3 b8 00 00 00 4c 89 e7
RSP: 0018:ffffc90004197b80 EFLAGS: 00000202
RAX: 0000000000000000 RBX: ffff88802a2f7608 RCX: ffffffff8202b6ec
RDX: ffff88807f0a9e00 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 0000000000000001 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90004197cfc
R13: 0000000000000000 R14: ffffc90004197cc8 R15: dffffc0000000000
 dput+0x1f/0x30 fs/dcache.c:847
 path_put fs/namei.c:568 [inline]
 terminate_walk+0x48e/0x680 fs/namei.c:696
 path_lookupat+0x212/0x770 fs/namei.c:2583
 filename_lookup+0x1e5/0x5b0 fs/namei.c:2595
 do_readlinkat+0xcf/0x390 fs/stat.c:537
 __do_sys_readlink fs/stat.c:574 [inline]
 __se_sys_readlink fs/stat.c:571 [inline]
 __x64_sys_readlink+0x78/0xc0 fs/stat.c:571
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7ff48a517d47
RSP: 002b:00007fffd507f678 EFLAGS: 00000246 ORIG_RAX: 0000000000000059
RAX: ffffffffffffffda RBX: 00007fffd507f688 RCX: 00007ff48a517d47
RDX: 0000000000000400 RSI: 00007fffd507f688 RDI: 00007fffd507fb68
RBP: 0000000000000400 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000010f R11: 0000000000000246 R12: 00007fffd507fb68
R13: 00007fffd507fad8 R14: 0000561a2fa2a2c0 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 4333 jiffies! g26945 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:27584 pid:17    tgid:17    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5188 [inline]
 __schedule+0xe37/0x5490 kernel/sched/core.c:6529
 __schedule_loop kernel/sched/core.c:6606 [inline]
 schedule+0xe7/0x350 kernel/sched/core.c:6621
 schedule_timeout+0x136/0x2a0 kernel/time/timer.c:2581
 rcu_gp_fqs_loop+0x1eb/0xb00 kernel/rcu/tree.c:2034
 rcu_gp_kthread+0x271/0x380 kernel/rcu/tree.c:2236
 kthread+0x2c1/0x3a0 kernel/kthread.c:389
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </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:48 [inline]
NMI backtrace for cpu 0 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:106 [inline]
NMI backtrace for cpu 0 skipped: idling at acpi_safe_halt+0x1a/0x20 drivers/acpi/processor_idle.c:111