1 files changed, 18 insertions, 3 deletions

diff --git a/drivers/cpufreq/cpufreq_stats.c b/drivers/cpufreq/cpufreq_stats.c
index 00d73fc8e4e2..4f1b8de2c9f3 100644
--- a/drivers/cpufreq/cpufreq_stats.c
+++ b/drivers/cpufreq/cpufreq_stats.c
@@ -165,17 +165,27 @@ static int freq_table_get_index(struct cpufreq_stats *stat, unsigned int freq)
         return -1;
 }
 
+/* should be called late in the CPU removal sequence so that the stats
+ * memory is still available in case someone tries to use it.
+ */
 static void cpufreq_stats_free_table(unsigned int cpu)
 {
         struct cpufreq_stats *stat = per_cpu(cpufreq_stats_table, cpu);
-        struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
-        if (policy && policy->cpu == cpu)
-                sysfs_remove_group(&policy->kobj, &stats_attr_group);
         if (stat) {
                 kfree(stat->time_in_state);
                 kfree(stat);
         }
         per_cpu(cpufreq_stats_table, cpu) = NULL;
+}
+
+/* must be called early in the CPU removal sequence (before
+ * cpufreq_remove_dev) so that policy is still valid.
+ */
+static void cpufreq_stats_free_sysfs(unsigned int cpu)
+{
+        struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+        if (policy && policy->cpu == cpu)
+                sysfs_remove_group(&policy->kobj, &stats_attr_group);
         if (policy)
                 cpufreq_cpu_put(policy);
 }
@@ -316,6 +326,9 @@ static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb,
         case CPU_ONLINE_FROZEN:
                 cpufreq_update_policy(cpu);
                 break;
+        case CPU_DOWN_PREPARE:
+                cpufreq_stats_free_sysfs(cpu);
+                break;
         case CPU_DEAD:
         case CPU_DEAD_FROZEN:
                 cpufreq_stats_free_table(cpu);
@@ -324,9 +337,11 @@ static int __cpuinit cpufreq_stat_cpu_callback(struct notifier_block *nfb,
         return NOTIFY_OK;
 }
 
+/* priority=1 so this will get called before cpufreq_remove_dev */
 static struct notifier_block cpufreq_stat_cpu_notifier __refdata =
 {
         .notifier_call = cpufreq_stat_cpu_callback,
+        .priority = 1,
 };
 
 static struct notifier_block notifier_policy_block = {