[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20190128154341.47195-101-sashal@kernel.org>
Date: Mon, 28 Jan 2019 10:40:18 -0500
From: Sasha Levin <sashal@...nel.org>
To: linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc: Thara Gopinath <thara.gopinath@...aro.org>,
Zhang Rui <rui.zhang@...el.com>,
Sasha Levin <sashal@...nel.org>, linux-pm@...r.kernel.org
Subject: [PATCH AUTOSEL 4.20 101/304] thermal: Fix locking in cooling device sysfs update cur_state
From: Thara Gopinath <thara.gopinath@...aro.org>
[ Upstream commit 68000a0d983f539c95ebe5dccd4f29535c7ac0af ]
Sysfs interface to update cooling device cur_state does not
currently holding cooling device lock sometimes leading to
stale values in cur_state if getting updated simultanelously
from user space and thermal framework. Adding the proper locking
code fixes this issue.
Signed-off-by: Thara Gopinath <thara.gopinath@...aro.org>
Signed-off-by: Zhang Rui <rui.zhang@...el.com>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
drivers/thermal/thermal_sysfs.c | 11 +++++++----
1 file changed, 7 insertions(+), 4 deletions(-)
diff --git a/drivers/thermal/thermal_sysfs.c b/drivers/thermal/thermal_sysfs.c
index 2241ceae7d7f..aa99edb4dff7 100644
--- a/drivers/thermal/thermal_sysfs.c
+++ b/drivers/thermal/thermal_sysfs.c
@@ -712,11 +712,14 @@ cur_state_store(struct device *dev, struct device_attribute *attr,
if ((long)state < 0)
return -EINVAL;
+ mutex_lock(&cdev->lock);
+
result = cdev->ops->set_cur_state(cdev, state);
- if (result)
- return result;
- thermal_cooling_device_stats_update(cdev, state);
- return count;
+ if (!result)
+ thermal_cooling_device_stats_update(cdev, state);
+
+ mutex_unlock(&cdev->lock);
+ return result ? result : count;
}
static struct device_attribute
--
2.19.1
Powered by blists - more mailing lists