hotplug / x86: Fix online state in cpu0 debug interface

_debug_hotplug_cpu() is a debug interface that puts cpu0 offline during
boot-up when CONFIG_DEBUG_HOTPLUG_CPU0 is set.  After cpu0 is put offline
in this interface, however, /sys/devices/system/cpu/cpu0/online still
shows 1 (online).

This patch fixes _debug_hotplug_cpu() to update dev->offline when CPU
online/offline operation succeeded.

Signed-off-by: Toshi Kani <toshi.kani@hp.com>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/arch/x86/kernel/topology.c b/arch/x86/kernel/topology.c
index 6e60b5fe2244..5823bbd668f4 100644
--- a/arch/x86/kernel/topology.c
+++ b/arch/x86/kernel/topology.c
@@ -72,16 +72,19 @@ int __ref _debug_hotplug_cpu(int cpu, int action)
                 ret = cpu_down(cpu);
                 if (!ret) {
                         pr_info("CPU %u is now offline\n", cpu);
+                        dev->offline = true;
                         kobject_uevent(&dev->kobj, KOBJ_OFFLINE);
                 } else
                         pr_debug("Can't offline CPU%d.\n", cpu);
                 break;
         case 1:
                 ret = cpu_up(cpu);
-                if (!ret)
+                if (!ret) {
+                        dev->offline = false;
                         kobject_uevent(&dev->kobj, KOBJ_ONLINE);
-                else
+                } else {
                         pr_debug("Can't online CPU%d.\n", cpu);
+                }
                 break;
         default:
                 ret = -EINVAL;