[PATCH 3.14 201/228] ACPI / processor: do not mark present at boot but not onlined CPU as onlined

From: Greg Kroah-Hartman
Date: Wed Jun 04 2014 - 19:57:52 EST


3.14-stable review patch. If anyone has any objections, please let me know.

------------------

From: Igor Mammedov <imammedo@xxxxxxxxxx>

commit 0b9d46dd7debf8e6dc8614106f1c1909fa8de64d upstream.

acpi_processor_add() assumes that present at boot CPUs
are always onlined, it is not so if a CPU failed to become
onlined. As result acpi_processor_add() will mark such CPU
device as onlined in sysfs and following attempts to
online/offline it using /sys/device/system/cpu/cpuX/online
attribute will fail.

Do not poke into device internals in acpi_processor_add()
and touch "struct device { .offline }" attribute, since
for CPUs onlined at boot it's set by:
topology_init() -> arch_register_cpu() -> register_cpu()
before ACPI device tree is parsed, and for hotplugged
CPUs it's set when userspace onlines CPU via sysfs.

Signed-off-by: Igor Mammedov <imammedo@xxxxxxxxxx>
Acked-by: Toshi Kani <toshi.kani@xxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/acpi/acpi_processor.c | 1 -
1 file changed, 1 deletion(-)

--- a/drivers/acpi/acpi_processor.c
+++ b/drivers/acpi/acpi_processor.c
@@ -405,7 +405,6 @@ static int acpi_processor_add(struct acp
goto err;

pr->dev = dev;
- dev->offline = pr->flags.need_hotplug_init;

/* Trigger the processor driver's .probe() if present. */
if (device_attach(dev) >= 0)


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