Halt poll cpuidle driver

modulename: cpuidle-haltpoll.ko

configname: CONFIG_HALTPOLL_CPUIDLE

Linux Kernel Configuration
└─>Power management and ACPI options
└─>CPU Idle
└─>Halt poll cpuidle driver
In linux kernel since version 5.1 (release Date: 2019-05-05)  
This option enables halt poll cpuidle driver, which allows to poll
before halting in the guest (more efficient than polling in the
host via halt_poll_ns for some scenarios).

source code: