From 9f5074ca7ade256fabc65d7eb12154fb7f2d3958 Mon Sep 17 00:00:00 2001
From: Andi Kleen <andi@firstfloor.org>
Date: Thu, 12 Feb 2009 13:39:31 +0100
Subject: [PATCH] --- yaml --- r: 138631 b: refs/heads/master c:
 d6b75584a3eaab8cb2ab3e8cf90c5e57c1928a85 h: refs/heads/master i:   138629:
 485ad283351ca79fe3d9872b69207e05421f3434   138627:
 c59a091c793717ac554a62f32aece1eb40fff2f1   138623:
 3d9b6851557dbe37145588f697eff2b499e851fb v: v3

---
 [refs]                                    |  2 +-
 trunk/arch/x86/kernel/cpu/mcheck/mce_64.c | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index feabe065fea6..bbdb013adf4e 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 5b4408fdaa62474dd9485cddb9126370d90d4b82
+refs/heads/master: d6b75584a3eaab8cb2ab3e8cf90c5e57c1928a85
diff --git a/trunk/arch/x86/kernel/cpu/mcheck/mce_64.c b/trunk/arch/x86/kernel/cpu/mcheck/mce_64.c
index 4e2b1bc5131c..1db94c0d5aaf 100644
--- a/trunk/arch/x86/kernel/cpu/mcheck/mce_64.c
+++ b/trunk/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;