From: Prarit Bhargava <prarit@redhat.com>
Date: Mon, 1 Dec 2008 09:47:59 -0500
Subject: [acpi] acpi_cpufreq: fix panic when removing module
Message-id: 20081201144758.17822.1507.sendpatchset@prarit.bos.redhat.com
O-Subject: [RHEL5.3 PATCH]: Fix panic when removing acpi_cpufreq module
Bugzilla: 472844
RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com>

Commit d63b373f11aabddade9f0f8574242ea1a75d587a introduced a panic in
acpi_cpufreq_exit().  This went unnoticed until we changed acpi-cpufreq
to a module.

acpi_perf_data is not a percpu variable.  Treat it accordingly when exitting.

Successfully compiled and tested by me.

diff --git a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
index f873c77..574702a 100644
--- a/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
+++ b/arch/i386/kernel/cpu/cpufreq/acpi-cpufreq.c
@@ -791,11 +791,16 @@ static int __init acpi_cpufreq_init(void)
 
 static void __exit acpi_cpufreq_exit(void)
 {
+	unsigned int i;
+
 	dprintk("acpi_cpufreq_exit\n");
 
 	cpufreq_unregister_driver(&acpi_cpufreq_driver);
 
-	free_percpu(acpi_perf_data);
+	for_each_possible_cpu(i) {
+		kfree(acpi_perf_data[i]);
+		acpi_perf_data[i] = NULL;
+	}
 
 	return;
 }