rcu: INFO: rcu_preempt detected stalls on CPUs/tasks:
rcu: 	Tasks blocked on level-0 rcu_node (CPUs 0-1): P4261/1:b..l
	(detected by 1, t=10502 jiffies, g=31965, q=100 ncpus=2)
task:udevd           state:R  running task     stack:23600 pid:4261  ppid:3638   flags:0x00004002
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 preempt_schedule_irq+0xbb/0x160 kernel/sched/core.c:6874
 irqentry_exit+0x63/0x70 kernel/entry/common.c:439
 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:check_kcov_mode kernel/kcov.c:193 [inline]
RIP: 0010:write_comp_data kernel/kcov.c:245 [inline]
RIP: 0010:__sanitizer_cov_trace_cmp8+0x32/0x80 kernel/kcov.c:293
Code: a4 e6 7f 7e 65 8b 15 a5 e6 7f 7e 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 57 83 b9 1c 16 00 00 00 74 4e 8b 91 f8 15 00 00 <83> fa 03 75 43 48 8b 91 00 16 00 00 44 8b 89 fc 15 00 00 49 c1 e1
RSP: 0018:ffffc90003ec7738 EFLAGS: 00000246
RAX: ffffffff8a1b6fee RBX: 0000000000000005 RCX: ffff88807c9f1dc0
RDX: 0000000000000000 RSI: 00007efdb9177fff RDI: 00007efdb913bfff
RBP: ffffc90003ec78f0 R08: ffff88807c9f1dc0 R09: 0000000000000003
R10: 0000000000000003 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff888023cfea80 R14: 00007efdb9177fff R15: 00007efdb913bfff
 mas_validate_limits lib/maple_tree.c:7146 [inline]
 mt_validate+0x1cae/0x4cb0 lib/maple_tree.c:7244
 validate_mm_mt+0xe2/0x440 mm/mmap.c:295
 validate_mm+0xe1/0x2e0 mm/mmap.c:332
 do_mas_align_munmap+0x1015/0x12b0 mm/mmap.c:2599
 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650
 __vm_munmap+0x1ac/0x2d0 mm/mmap.c:2936
 __do_sys_munmap mm/mmap.c:2961 [inline]
 __se_sys_munmap mm/mmap.c:2958 [inline]
 __x64_sys_munmap+0x5c/0x70 mm/mmap.c:2958
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7efdb891e097
RSP: 002b:00007ffed04f2888 EFLAGS: 00000246 ORIG_RAX: 000000000000000b
RAX: ffffffffffffffda RBX: 000055a681ea1400 RCX: 00007efdb891e097
RDX: 000055a681eb3ff0 RSI: 0000000000000200 RDI: 00007efdb900e000
RBP: 000055a681eb3ff0 R08: 0000000000000000 R09: 0000000000000400
R10: 000055a681eb3fe0 R11: 0000000000000246 R12: 00007efdb913d880
R13: 00007efdb914239c R14: 0000000000000024 R15: 0000000000000001
 </TASK>
rcu: rcu_preempt kthread starved for 9899 jiffies! g31965 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:28080 pid:16    ppid:2      flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5245 [inline]
 __schedule+0x11d1/0x40e0 kernel/sched/core.c:6562
 schedule+0xb9/0x180 kernel/sched/core.c:6638
 schedule_timeout+0x184/0x2d0 kernel/time/timer.c:2168
 rcu_gp_fqs_loop+0x303/0x1340 kernel/rcu/tree.c:1706
 rcu_gp_kthread+0x99/0x3b0 kernel/rcu/tree.c:1905
 kthread+0x29d/0x330 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:741