rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P3840/1:b..l
	(detected by 0, t=10502 jiffies, g=9517, q=261 ncpus=2)
task:dhcpcd-run-hook state:R  running task     stack:23880 pid:3840  ppid:3217   flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 preempt_schedule_irq+0xf7/0x1c0 kernel/sched/core.c:6870
 irqentry_exit+0x53/0x80 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:653
RIP: 0010:check_kcov_mode kernel/kcov.c:184 [inline]
RIP: 0010:__sanitizer_cov_trace_pc+0x32/0x60 kernel/kcov.c:207
Code: e4 db 77 7e 65 8b 15 e5 db 77 7e f7 c2 00 01 ff 00 74 11 f7 c2 00 01 00 00 74 35 83 b9 1c 16 00 00 00 74 2c 8b 91 f8 15 00 00 <83> fa 02 75 21 48 8b 91 00 16 00 00 48 8b 32 48 8d 7e 01 8b 89 fc
RSP: 0018:ffffc90004ca7338 EFLAGS: 00000246
RAX: ffffffff8a821244 RBX: 0000000000000001 RCX: ffff888027515940
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: ffffc90004ca7530 R08: ffffffff8a8211d2 R09: ffffffff8a820e8b
R10: 0000000000000003 R11: ffff888027515940 R12: 0000000000000007
R13: 00007fecb975bfff R14: dffffc0000000000 R15: 0000000000001000
 mas_validate_gaps lib/maple_tree.c:7007 [inline]
 mt_validate+0x3844/0x5ad0 lib/maple_tree.c:7240
 validate_mm_mt+0x165/0x670 mm/mmap.c:295
 validate_mm+0x16e/0x380 mm/mmap.c:332
 do_mas_align_munmap+0x132d/0x15f0 mm/mmap.c:2589
 do_mas_munmap+0x246/0x2b0 mm/mmap.c:2640
 mmap_region+0x8e6/0x1fa0 mm/mmap.c:2688
 do_mmap+0x8c5/0xf60 mm/mmap.c:1425
 vm_mmap_pgoff+0x1ca/0x2d0 mm/util.c:520
 ksys_mmap_pgoff+0x4f5/0x6d0 mm/mmap.c:1471
 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: 0033:0x7fecb974ab74
RSP: 002b:00007fff7658a938 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fff7658a9e8 RCX: 00007fecb974ab74
RDX: 0000000000000003 RSI: 0000000000002000 RDI: 00007fecb94a5000
RBP: 00007fff7658ad10 R08: 0000000000000003 R09: 0000000000022000
R10: 0000000000000812 R11: 0000000000000246 R12: 00007fecb972dfc0
R13: 00007fff7658ad98 R14: 0000000000021bd8 R15: 0000000000000000
 </TASK>
rcu: rcu_preempt kthread starved for 9886 jiffies! g9517 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:26712 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x142d/0x4550 kernel/sched/core.c:6558
 schedule+0xbf/0x180 kernel/sched/core.c:6634
 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:308
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1 skipped: idling at native_safe_halt arch/x86/include/asm/irqflags.h:51 [inline]
NMI backtrace for cpu 1 skipped: idling at arch_safe_halt arch/x86/include/asm/irqflags.h:89 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_safe_halt drivers/acpi/processor_idle.c:112 [inline]
NMI backtrace for cpu 1 skipped: idling at acpi_idle_do_entry+0x10f/0x340 drivers/acpi/processor_idle.c:572
sched: RT throttling activated