struct acpi_scan_handler has a detach callback that is used to remove a driver when a bus is changed. When interacting with an eject-request, the detach callback is called before _EJ0. This means the ACPI processor driver can't use _STA to determine if a CPU has been made not-present, or some of the other _STA bits have been changed. acpi_processor_remove() needs to know the value of _STA after _EJ0 has been called. Add a post_eject callback to struct acpi_scan_handler. This is called after acpi_scan_hot_remove() has successfully called _EJ0. Because acpi_scan_check_and_detach() also clears the handler pointer, it needs to be told if the caller will go on to call acpi_bus_post_eject(), so that acpi_device_clear_enumerated() and clearing the handler pointer can be deferred. An extra flag is added to flags field introduced in the previous patch to achieve this. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Gavin Shan <gshan@redhat.com> Tested-by: Miguel Luis <miguel.luis@oracle.com> Tested-by: Vishnu Pajjuri <vishnu@os.amperecomputing.com> Tested-by: Jianyong Wu <jianyong.wu@arm.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Hanjun Guo <guohanjun@huawei.com> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> Link: https://lore.kernel.org/r/20240529133446.28446-11-Jonathan.Cameron@huawei.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>