576K [ 1.581108] CPU 0/0x20 -> Node 0 [ 1.596193] CPU 0 microcode level: 0xffff0008 It doesn't have correct physical processor id and will get an error: [ 38.840859] CPU0 attaching sched-domain: [ 38.848287] domain 0: span 0,8,72 level SIBLING [ 38.851151] groups: 0 8 72 [ 38.858137] domain 1: span 0,8-15,72-79 level MC [ 38.868944] groups: 0,8,72 9,73 10,74 11,75 12,76 13,77 14,78 15,79 [ 38.881383] ERROR: parent span is not a superset of domain->span [ 38.890724] domain 2: span 0-7,64-71 level CPU [ 38.899237] ERROR: domain->groups does not contain CPU0 [ 38.909229] groups: 8-15,72-79 [ 38.912547] ERROR: groups don't span domain->span [ 38.919665] domain 3: span 0-127 level NODE [ 38.930739] groups: 0-7,64-71 8-15,72-79 16-23,80-87 24-31,88-95 32-39,96-103 40-47,104-111 48-55,112-119 56-63,120-127 it turns out: we can not use current_cpu_data in phys_pgd_id for x2apic. identify_boot_cpu() is called by check_bugs() before smp_prepare_cpus() and till smp_prepare_cpus() current_cpu_data for bsp is assigned with boot_cpu_data. Just make phys_pkg_id for x2apic is aligned to xapic. Signed-off-by: Yinghai Lu Acked-by: Suresh Siddha Cc: Andrew Morton LKML-Reference: <4A6ADD0D.10002@kernel.org> Signed-off-by: Ingo Molnar K¹o}š