On Mon, Nov 11, 2013 at 11:52:30AM +0900, HATAYAMA Daisuke wrote: [..] > Looking at my past investigation, kernel/mpparse.c, mm/amdtopology.c and > platform/visws/visws_quirks.c assumes that boot_cpu_physical_apicid > has initial apicid of the BSP, not the current actual booting-up cpu. > > These three are called in get_smp_config() below. If either of them is > called actually, boot_cpu_physical_apicid has the apicid different from > the current actual booting-up cpu temporarily. But init_apic_mappings() > soon modifies back the value to the one obtained by read_apic_id(). > > /* > * Read APIC and some other early information from ACPI tables. > */ > acpi_boot_init(); > sfi_init(); > x86_dtb_init(); > > /* > * get boot-time SMP configuration: > */ > if (smp_found_config) > get_smp_config(); > > prefill_possible_map(); > > init_cpu_to_node(); > > init_apic_mappings(); > > So, thanks to init_apic_mappings(), the patch set would work without the > first patch... This is a careless point in this patch set. > If init_apic_mappings(), is making sure that boot_cpu_physical_apicid is apic id of booting processor, and you don't need first patch of your series, then I think atleast re-post your patch series without first patch. And then there can be another series which looks into whether we need two different variables or not and if we do, then a separate variable bsp_physical_apicid will track the bsp id as reported by BIOS and boot_cpu_physical_apicid will track apic id of booting cpu. This might a very big and slow cleanup. So I think blocking the first patch series behind it might not make much sense. Thanks Vivek
