rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P17860/1:b..l
	(detected by 1, t=10502 jiffies, g=95477, q=233 ncpus=2)
task:sed             state:R  running task     stack:22616 pid:17860 ppid:17857  flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6873
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:seqcount_lockdep_reader_access+0x1d2/0x220 include/linux/seqlock.h:105
Code: 5e e8 12 8a 95 ff 4d 85 f6 48 bb 00 00 00 00 00 fc ff df 75 07 e8 fe 89 95 ff eb 06 e8 f7 89 95 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:ffffc9000ced7700 EFLAGS: 00000293
RAX: ffffffff81f52059 RBX: dffffc0000000000 RCX: ffff88802c421dc0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc9000ced77b0 R08: ffffffff81f52034 R09: fffffbfff1d417ce
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff920019daee0
R13: ffffc9000ced7720 R14: 0000000000000200 R15: 0000000000000046
 __follow_mount_rcu fs/namei.c:1509 [inline]
 handle_mounts fs/namei.c:1534 [inline]
 step_into+0x7cd/0x1070 fs/namei.c:1836
 walk_component fs/namei.c:2004 [inline]
 link_path_walk+0x72c/0xee0 fs/namei.c:2325
 path_lookupat+0xa9/0x450 fs/namei.c:2478
 filename_lookup+0x251/0x600 fs/namei.c:2508
 user_path_at_empty+0x3e/0x60 fs/namei.c:2905
 user_path_at include/linux/namei.h:57 [inline]
 user_statfs fs/statfs.c:103 [inline]
 __do_sys_statfs fs/statfs.c:195 [inline]
 __se_sys_statfs fs/statfs.c:192 [inline]
 __x64_sys_statfs+0x116/0x240 fs/statfs.c:192
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fd3bab4768a
RSP: 002b:00007ffe51ca4058 EFLAGS: 00000246 ORIG_RAX: 0000000000000089
RAX: ffffffffffffffda RBX: 00007fd3baa6c4f8 RCX: 00007fd3bab4768a
RDX: 00007fd3baa6e19c RSI: 00007ffe51ca40d0 RDI: 00007fd3baa64723
RBP: 00007fd3baa64723 R08: 0000000000000000 R09: 000000000000000d
R10: 00007ffe51ca3e80 R11: 0000000000000246 R12: 00007ffe51ca40d0
R13: 00007ffe51ca4248 R14: 00007ffe51ca4270 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread timer wakeup didn't happen for 10135 jiffies! g95477 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu: 	Possible timer handling issue on cpu=0 timer-softirq=48942
rcu: rcu_preempt kthread starved for 10141 jiffies! g95477 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:26712 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0x143f/0x4570 kernel/sched/core.c:6561
 schedule+0xbf/0x180 kernel/sched/core.c:6637
 schedule_timeout+0x1b9/0x300 kernel/time/timer.c:1965
 rcu_gp_fqs_loop+0x2d2/0x1150 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0xa3/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </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 default_idle+0xb/0x10 arch/x86/kernel/process.c:735