ACPI: fix "buggy BIOS check" when CPUs are hot removed

Alok Kataria akataria at
Mon Jun 23 23:41:11 UTC 2008

Already in mainline....required for CPU hotplug.


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commit ba62b077871a5255e271f4fdae57167651839277
Author: Alok Kataria <akataria at>
Date:   Tue Apr 8 17:41:56 2008 -0700

    acpi: fix "buggy BIOS check" when CPUs are hot removed
    Fixes a BUG in ACPI hotplugging.
    processor_device_array[pr->id] needs to be set to NULL when removing a CPU.
    Else the "buggy BIOS check" in acpi_processor_start mistakenly fires when a
    CPU is removed from the system and then later re-added.
    Signed-off-by: Alok N Kataria <akataria at>
    Signed-off-by: Dan Arai <arai at>
    Cc: Len Brown <lenb at>
    Cc: <stable at>
    Signed-off-by: Andrew Morton <akpm at>
    Signed-off-by: Linus Torvalds <torvalds at>

Index: ubuntu-hardy/drivers/acpi/processor_core.c
--- ubuntu-hardy.orig/drivers/acpi/processor_core.c	2008-06-06 10:59:05.000000000 -0700
+++ ubuntu-hardy/drivers/acpi/processor_core.c	2008-06-12 10:28:15.000000000 -0700
@@ -792,7 +792,7 @@
 	processors[pr->id] = NULL;
+	processor_device_array[pr->id] = NULL;
 	return 0;

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