3 files changed, 14 insertions, 5 deletions
diff --git a/drivers/cpufreq/acpi-cpufreq.c b/drivers/cpufreq/acpi-cpufreq.c
index 15b921a9248c..cec1ee2d2f74 100644
--- a/drivers/cpufreq/acpi-cpufreq.c
+++ b/drivers/cpufreq/acpi-cpufreq.c
@@ -149,6 +149,9 @@ static ssize_t show_freqdomain_cpus(struct cpufreq_policy *policy, char *buf)
 {
 	struct acpi_cpufreq_data *data = policy->driver_data;
 
+	if (unlikely(!data))
+		return -ENODEV;
+
 	return cpufreq_show_cpus(data->freqdomain_cpus, buf);
 }
 
@@ -375,12 +378,11 @@ static unsigned int get_cur_freq_on_cpu(unsigned int cpu)
 
 	pr_debug("get_cur_freq_on_cpu (%d)\n", cpu);
 
-	policy = cpufreq_cpu_get(cpu);
+	policy = cpufreq_cpu_get_raw(cpu);
 	if (unlikely(!policy))
 		return 0;
 
 	data = policy->driver_data;
-	cpufreq_cpu_put(policy);
 	if (unlikely(!data || !data->freq_table))
 		return 0;
 
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 6633b3fa996e..25c4c15103a0 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -238,13 +238,13 @@ int cpufreq_generic_init(struct cpufreq_policy *policy,
 }
 EXPORT_SYMBOL_GPL(cpufreq_generic_init);
 
-/* Only for cpufreq core internal use */
-static struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
+struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
 {
 	struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
 
 	return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL;
 }
+EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw);
 
 unsigned int cpufreq_generic_get(unsigned int cpu)
 {
@@ -1436,8 +1436,10 @@ static void cpufreq_offline_finish(unsigned int cpu)
 	 * since this is a core component, and is essential for the
 	 * subsequent light-weight ->init() to succeed.
 	 */
-	if (cpufreq_driver->exit)
+	if (cpufreq_driver->exit) {
 		cpufreq_driver->exit(policy);
+		policy->freq_table = NULL;
+	}
 }
 
 /**
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 3af9dd7332e6..aa33b92b3e3e 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c
@@ -776,6 +776,11 @@ static inline void intel_pstate_sample(struct cpudata *cpu)
 	local_irq_save(flags);
 	rdmsrl(MSR_IA32_APERF, aperf);
 	rdmsrl(MSR_IA32_MPERF, mperf);
+	if (cpu->prev_mperf == mperf) {
+		local_irq_restore(flags);
+		return;
+	}
+
 	tsc = rdtsc();
 	local_irq_restore(flags);