A new driver already queued in the power management code for the Linux 5.7 cycle not opening up until April is a “tiny power button” driver. This ACPI tiny power button driver is not for a physically tiny power button, but rather a simple ACPI power button driver out of Intel intended for virtual machines and more basic than the generic ACPI button driver given the limited scope of VMs.
Virtual machines tend to rely on simulated ACPI power button events for having the VM power off gracefully but can rely on a daemon like acpid or systemd-logind for processing the said event.
[Source: Phoronix]
