Linux to date does not evaluate the Processor._INI method when a processor is added to a system. Firmware on future systems will require that it does for the operation to be successful.
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According to ACPI spec the control method is run only when OSPM load a dscription table. If the device becomes present after the table has already been loaded, OSPM won't evaluate the _INI method , nor examine the children for _INI method. Is it necessary to execute the Processor._INI method when a processor is added to a system if the _INI method is evaluated when the table is loaded dynamically? (_INI method is executed in the ACPICA after completing the load of static DSDT/SSDT.)
According to the ACPI spec, the _INI method is only executed only when OSPM loads a decription table. If the device becomes present after the table has already been loaded, OSPM will not evaluate the _INI method, nor examine the children for _INI methods. Based on the above description it seems unnecessary to evaluate the processor._INI after hot-add operation. So the bug will be rejected. Thanks.