[PATCH v4 1/3] acpi : cpu hot-remove returns error when cpu_down() fails

[Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>]

Even if cpu_down() fails, acpi_processor_remove() continues to remove the cpu.
But in this case, it should return error number since some process may run on
the cpu. If the cpu has a running process and the cpu is turned the power off,
the system may not work well.

Reviewed-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

---
 drivers/acpi/processor_driver.c |   18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

Index: linux-3.5-rc6/drivers/acpi/processor_driver.c
===================================================================
--- linux-3.5-rc6.orig/drivers/acpi/processor_driver.c	2012-07-08 09:23:56.000000000 +0900
+++ linux-3.5-rc6/drivers/acpi/processor_driver.c	2012-07-13 15:11:06.135541317 +0900
@@ -610,7 +610,7 @@ err_free_pr:
 static int acpi_processor_remove(struct acpi_device *device, int type)
 {
 	struct acpi_processor *pr = NULL;
-
+	int ret;

 	if (!device || !acpi_driver_data(device))
 		return -EINVAL;
@@ -621,8 +621,9 @@ static int acpi_processor_remove(struct
 		goto free;

 	if (type == ACPI_BUS_REMOVAL_EJECT) {
-		if (acpi_processor_handle_eject(pr))
-			return -EINVAL;
+		ret = acpi_processor_handle_eject(pr);
+		if (ret)
+			return ret;
 	}

 	acpi_processor_power_exit(pr, device);
@@ -841,12 +842,17 @@ static acpi_status acpi_processor_hotadd

 static int acpi_processor_handle_eject(struct acpi_processor *pr)
 {
-	if (cpu_online(pr->id))
-		cpu_down(pr->id);
+	int ret = 0;
+
+	if (cpu_online(pr->id)) {
+		ret = cpu_down(pr->id);
+		if (ret)
+			return ret;
+	}

 	arch_unregister_cpu(pr->id);
 	acpi_unmap_lsapic(pr->id);
-	return (0);
+	return ret;
 }
 #else
 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)