1 files changed, 23 insertions, 0 deletions

diff --git a/arch/x86/kernel/cpu/mcheck/mce_64.c b/arch/x86/kernel/cpu/mcheck/mce_64.c
index 4e2b1bc5131c..1db94c0d5aaf 100644
--- a/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/arch/x86/kernel/cpu/mcheck/mce_64.c
@@ -906,6 +906,27 @@ static __cpuinit void mce_remove_device(unsigned int cpu)
         cpu_clear(cpu, mce_device_initialized);
 }
 
+/* Make sure there are no machine checks on offlined CPUs. */
+static void __cpuexit mce_disable_cpu(void *h)
+{
+        int i;
+
+        if (!mce_available(&current_cpu_data))
+                return;
+        for (i = 0; i < banks; i++)
+                wrmsrl(MSR_IA32_MC0_CTL + i*4, 0);
+}
+
+static void __cpuexit mce_reenable_cpu(void *h)
+{
+        int i;
+
+        if (!mce_available(&current_cpu_data))
+                return;
+        for (i = 0; i < banks; i++)
+                wrmsrl(MSR_IA32_MC0_CTL + i*4, bank[i]);
+}
+
 /* Get notified when a cpu comes on/off. Be hotplug friendly. */
 static int __cpuinit mce_cpu_callback(struct notifier_block *nfb,
                                       unsigned long action, void *hcpu)
@@ -929,11 +950,13 @@ static int __cpuinit mce_cpu_callback(struct notifier_block *nfb,
         case CPU_DOWN_PREPARE:
         case CPU_DOWN_PREPARE_FROZEN:
                 del_timer_sync(t);
+                smp_call_function_single(cpu, mce_disable_cpu, NULL, 1);
                 break;
         case CPU_DOWN_FAILED:
         case CPU_DOWN_FAILED_FROZEN:
                 t->expires = round_jiffies_relative(jiffies + next_interval);
                 add_timer_on(t, cpu);
+                smp_call_function_single(cpu, mce_reenable_cpu, NULL, 1);
                 break;
         }
         return NOTIFY_OK;