[PATCH 4.9 34/91] PM / devfreq: Check NULL governor in available_governors_show

[Greg Kroah-Hartman]

From: Leonard Crestez <leonard.crestez@xxxxxxx>

commit d68adc8f85cd757bd33c8d7b2660ad6f16f7f3dc upstream.

The governor is initialized after sysfs attributes become visible so in
theory the governor field can be NULL here.

Fixes: bcf23c79c4e46 ("PM / devfreq: Fix available_governor sysfs")
Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Reviewed-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/devfreq/devfreq.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -982,7 +982,7 @@ static ssize_t available_governors_show(
 	 * The devfreq with immutable governor (e.g., passive) shows
 	 * only own governor.
 	 */
-	if (df->governor->immutable) {
+	if (df->governor && df->governor->immutable) {
 		count = scnprintf(&buf[count], DEVFREQ_NAME_LEN,
 				   "%s ", df->governor_name);
 	/*