--- arch/x86/kernel/apic/probe_32.c

+++ arch/x86/kernel/apic/probe_32.c

@@ -54,6 +54,31 @@ late_initcall(print_ipi_mode);

void default_setup_apic_routing(void)

{

+ int version = apic_version[boot_cpu_physical_apicid];

+

+ if (num_possible_cpus() > 8) {

+ switch (boot_cpu_data.x86_vendor) {

+ case X86_VENDOR_INTEL:

+ if (!APIC_XAPIC(version)) {

+ def_to_bigsmp = 0;

+ break;

+ }

+ /* If P4 and above fall through */

+ case X86_VENDOR_AMD:

+ def_to_bigsmp = 1;

+ }

+ }

+

+#ifdef CONFIG_X86_BIGSMP

+ generic_bigsmp_probe();

+#endif

+

+ if (apic->setup_apic_routing)

+ apic->setup_apic_routing();

+}

+

+void setup_apic_flat_routing(void)

+{

#ifdef CONFIG_X86_IO_APIC

printk(KERN_INFO

"Enabling APIC mode: Flat. Using %d I/O APICs\n",

@@ -103,7 +128,7 @@ struct apic apic_default = {

.init_apic_ldr = default_init_apic_ldr,

.ioapic_phys_id_map = default_ioapic_phys_id_map,

- .setup_apic_routing = default_setup_apic_routing,

+ .setup_apic_routing = setup_apic_flat_routing,

.multi_timer_check = NULL,

.apicid_to_node = default_apicid_to_node,

.cpu_to_logical_apicid = default_cpu_to_logical_apicid,