cpufreq: prevent lockup on reading scaling_available_frequencies

When scaling_available_frequencies is read on an offlined cpu, then
either lockup or junk values are displayed. This is caused by
freed freq_table, which policy is using.

Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index ef5ed9470de9..25c4c15103a0 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -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;
+        }
 }
 
 /**