[PATCH 07/15] thermal: sysfs: lock tz while on policy properties

Eduardo Valentin
2016-05-31T06:32:26Z

Serialized calls to tz.ops in user facing
sysfs handler policy_show().
policy_store() is already locked by
the thermal core.

Cc: Zhang Rui <rui.zhang@intel.com>
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Eduardo Valentin <edubezval@gmail.com>
---
drivers/thermal/thermal_sysfs.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
index dcaeb17..234eb18 100644
--- a/drivers/thermal/thermal_sysfs.c
+++ b/drivers/thermal/thermal_sysfs.c
@@ -311,8 +311,14 @@ static ssize_t
policy_show(struct device *dev, struct device_attribute *devattr, char *buf)
{
struct thermal_zone_device *tz = to_thermal_zone(dev);
+ char *name;

- return sprintf(buf, "%s\n", tz->governor->name);
+ /* locking the zone because governor->name does not change */
+ mutex_lock(&tz->lock);
+ name = tz->governor->name;
+ mutex_unlock(&tz->lock);
+
+ return sprintf(buf, "%s\n", name);
}

static ssize_t
--
2.1.4