They have been module options, not prefixed kernel parameters so far,
and the prefix was just the module name.
So it just strikes back, that acpi uses generic names for the modules,
there would have been no problem if "power" would be called "acpi_power"
and the options would just be ï"acpi.acpica_version" and
"acpi_power.nocheck".
But well, there are driver modules just called "option", so acpi is not
that bad. :)
I think the generic params code should be fixed to handle this.
We could try to look up existing directories to use instead of expecting
that we need to create and own them. I guess,