From a3301b751b19f0efbafddc4034f8e7ce6bf3007b Mon Sep 17 00:00:00 2001
From: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Date: Sat, 14 Jan 2012 08:11:31 +0530
Subject: [PATCH] x86/mce: Fix CPU hotplug and suspend regression related to
 MCE

Commit 8a25a2fd126c ("cpu: convert 'cpu' and 'machinecheck' sysdev_class
to a regular subsystem") changed how things are dealt with in the MCE
subsystem.  Some of the things that got broken due to this are CPU
hotplug and suspend/hibernate.

MCE uses per_cpu allocations of struct device.  So, when a CPU goes
offline and comes back online, in order to ensure that we start from a
clean slate with respect to the MCE subsystem, zero out the entire
per_cpu device structure to 0 before using it.

Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 arch/x86/kernel/cpu/mcheck/mce.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index f22a9f7f6390a6..29ba3297e48006 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -2011,7 +2011,7 @@ static __cpuinit int mce_device_create(unsigned int cpu)
 	if (!mce_available(&boot_cpu_data))
 		return -EIO;
 
-	memset(&dev->kobj, 0, sizeof(struct kobject));
+	memset(dev, 0, sizeof(struct device));
 	dev->id  = cpu;
 	dev->bus = &mce_subsys;
 
-- 
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