Merge branch 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (25 commits)
  x86: Fix out of order of gsi
  x86: apic: Fix mismerge, add arch_probe_nr_irqs() again
  x86, irq: Keep chip_data in create_irq_nr and destroy_irq
  xen: Remove unnecessary arch specific xen irq functions.
  smp: Use nr_cpus= to set nr_cpu_ids early
  x86, irq: Remove arch_probe_nr_irqs
  sparseirq: Use radix_tree instead of ptrs array
  sparseirq: Change irq_desc_ptrs to static
  init: Move radix_tree_init() early
  irq: Remove unnecessary bootmem code
  x86: Add iMac9,1 to pci_reboot_dmi_table
  x86: Convert i8259_lock to raw_spinlock
  x86: Convert nmi_lock to raw_spinlock
  x86: Convert ioapic_lock and vector_lock to raw_spinlock
  x86: Avoid race condition in pci_enable_msix()
  x86: Fix SCI on IOAPIC != 0
  x86, ia32_aout: do not kill argument mapping
  x86, irq: Move __setup_vector_irq() before the first irq enable in cpu online path
  x86, irq: Update the vector domain for legacy irqs handled by io-apic
  x86, irq: Don't block IRQ0_VECTOR..IRQ15_VECTOR's on all cpu's
  ...

1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index fbcddc5abe25..d80930d58dae 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1794,6 +1794,12 @@ and is between 256 and 4096 characters. It is defined in the file
                         purges which is reported from either PAL_VM_SUMMARY or
                         SAL PALO.
 
+        nr_cpus=        [SMP] Maximum number of processors that an SMP kernel
+                        could support.  nr_cpus=n : n >= 1 limits the kernel to
+                        supporting 'n' processors. Later in runtime you can not
+                        use hotplug cpu feature to put more cpu back to online.
+                        just like you compile the kernel NR_CPUS=n
+
         nr_uarts=       [SERIAL] maximum number of UARTs to be registered.
 
         numa_zonelist_order= [KNL, BOOT] Select zonelist order for NUMA.