From 949ec325c79add68af13705b68a885a1efb84234 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 30 Jan 2008 13:30:46 +0100 Subject: [PATCH] x86: set cpu_index to nr_cpus instead of 0 Some BIOSes that support two/four dualcore/quadcore systems, will get: ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled) Processor #0 15:1 APIC version 16 ACPI: LAPIC (acpi_id[0x02] lapic_id[0x01] enabled) Processor #1 15:1 APIC version 16 ACPI: LAPIC (acpi_id[0x03] lapic_id[0x02] enabled) Processor #2 15:1 APIC version 16 ACPI: LAPIC (acpi_id[0x04] lapic_id[0x03] enabled) Processor #3 15:1 APIC version 16 ACPI: LAPIC (acpi_id[0x05] lapic_id[0x84] disabled) ACPI: LAPIC (acpi_id[0x06] lapic_id[0x85] disabled) ACPI: LAPIC (acpi_id[0x07] lapic_id[0x86] disabled) ACPI: LAPIC (acpi_id[0x08] lapic_id[0x87] disabled) ACPI: LAPIC (acpi_id[0x09] lapic_id[0x88] disabled) ACPI: LAPIC (acpi_id[0x0a] lapic_id[0x89] disabled) ACPI: LAPIC (acpi_id[0x0b] lapic_id[0x8a] disabled) ACPI: LAPIC (acpi_id[0x0c] lapic_id[0x8b] disabled) ACPI: LAPIC (acpi_id[0x0d] lapic_id[0x8c] disabled) ACPI: LAPIC (acpi_id[0x0e] lapic_id[0x8d] disabled) ACPI: LAPIC (acpi_id[0x0f] lapic_id[0x8e] disabled) ACPI: LAPIC (acpi_id[0x10] lapic_id[0x8f] disabled) SMP: Allowing 16 CPUs, 12 hotplug CPUs the /proc/cpuinfo will show a bunch of NULL cpus with cpu_index=0 so assign impossible cpu_index value at first instead of 0. Signed-off-by: Yinghai Lu Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- arch/x86/kernel/smpboot_64.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/x86/kernel/smpboot_64.c b/arch/x86/kernel/smpboot_64.c index ddefb38c53fb..8ac8eb620428 100644 --- a/arch/x86/kernel/smpboot_64.c +++ b/arch/x86/kernel/smpboot_64.c @@ -861,6 +861,18 @@ void __init smp_set_apicids(void) x86_cpu_to_apicid_ptr = NULL; } +static void __init smp_cpu_index_default(void) +{ + int i; + struct cpuinfo_x86 *c; + + for_each_cpu_mask(i, cpu_possible_map) { + c = &cpu_data(i); + /* mark all to hotplug */ + c->cpu_index = NR_CPUS; + } +} + /* * Prepare for SMP bootup. The MP table or ACPI has been read * earlier. Just do some sanity checking here and enable APIC mode. @@ -868,6 +880,7 @@ void __init smp_set_apicids(void) void __init smp_prepare_cpus(unsigned int max_cpus) { nmi_watchdog_default(); + smp_cpu_index_default(); current_cpu_data = boot_cpu_data; current_thread_info()->cpu = 0; /* needed? */ smp_set_apicids();