linux-kernel - [PATCH 06/13] thermal/drivers/hisi: Remove pointless lock

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1504082857-21702-6-git-send-email-daniel.lezcano@linaro.org>
Date:   Wed, 30 Aug 2017 10:47:30 +0200
From:   Daniel Lezcano <daniel.lezcano@...aro.org>
To:     rui.zhang@...el.com, edubezval@...il.com
Cc:     daniel.lezcano@...aro.org, linux-pm@...r.kernel.org,
        kevin.wangtao@...aro.org, leo.yan@...aro.org,
        linux-kernel@...r.kernel.org (open list)
Subject: [PATCH 06/13] thermal/drivers/hisi: Remove pointless lock

The threaded interrupt inspect the sensors structure to look in the temp
threshold field, but this field is read-only in all the code, except in the
probe function before the threaded interrupt is set. In other words there
is not race window in the threaded interrupt when reading the field value.

Signed-off-by: Daniel Lezcano <daniel.lezcano@...aro.org>
---
 drivers/thermal/hisi_thermal.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/thermal/hisi_thermal.c b/drivers/thermal/hisi_thermal.c
index 524310d..6f0dab1 100644
--- a/drivers/thermal/hisi_thermal.c
+++ b/drivers/thermal/hisi_thermal.c
@@ -221,14 +221,10 @@ static irqreturn_t hisi_thermal_alarm_irq(int irq, void *dev)
 static irqreturn_t hisi_thermal_alarm_irq_thread(int irq, void *dev)
 {
 	struct hisi_thermal_data *data = dev;
-	struct hisi_thermal_sensor *sensor;
-
-	mutex_lock(&data->thermal_lock);
-	sensor = &data->sensors;
+	struct hisi_thermal_sensor *sensor = &data->sensors;
 
 	dev_crit(&data->pdev->dev, "THERMAL ALARM: T > %d\n",
 		 sensor->thres_temp);
-	mutex_unlock(&data->thermal_lock);
 
 	thermal_zone_device_update(data->sensors.tzd,
 				   THERMAL_EVENT_UNSPECIFIED);
-- 
2.7.4