ACPI / processor: move try_offline_node() after acpi_unmap_lsapic()

try_offline_node() checks that all CPUs associated with the given
node have been removed by using cpu_present_bits.  If all cpus
related to that node have been removed, try_offline_node() clears
the node information.

However, try_offline_node() called from acpi_processor_remove() never
clears the node information.  For disabling cpu_present_bits,
acpi_unmap_lsapic() needs be called.  Yet, acpi_unmap_lsapic() is
called after try_offline_node() has run.  So when try_offline_node()
runs, the CPU's cpu_present_bits is always set.

Fix the issue by moving try_offline_node() after acpi_unmap_lsapic().

The problem fixed here was uncovered by commit cecdb19 "ACPI / scan:
Change the implementation of acpi_bus_trim()".

[rjw: Changelog]
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: 3.9+ <stable@vger.kernel.org> # 3.9+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/acpi_processor.c b/drivers/acpi/acpi_processor.c
index fd6c51cc3acb52fb49adf5c7885f6ecd318fa2e3..5a74a9c1e42c85a6999f9a4ef780728f8bdc5bcb 100644 (file)
--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -451,7 +451,6 @@ static void acpi_processor_remove(struct acpi_device *device)
        /* Clean up. */
        per_cpu(processor_device_array, pr->id) = NULL;
        per_cpu(processors, pr->id) = NULL;
-       try_offline_node(cpu_to_node(pr->id));
 
        /* Remove the CPU. */
        get_online_cpus();
@@ -459,6 +458,8 @@ static void acpi_processor_remove(struct acpi_device *device)
        acpi_unmap_lsapic(pr->id);
        put_online_cpus();
 
+       try_offline_node(cpu_to_node(pr->id));
+
  out:
        free_cpumask_var(pr->throttling.shared_cpu_map);
        kfree(pr);