linux-kernel - [PATCH] power_supply: Register cooling device outside of probe

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-next>] [day] [month] [year] [list]

Message-ID: <1639393841-17444-1-git-send-email-quic_manafm@quicinc.com>
Date:   Mon, 13 Dec 2021 16:40:41 +0530
From:   Manaf Meethalavalappu Pallikunhi <quic_manafm@...cinc.com>
To:     Sebastian Reichel <sre@...nel.org>
CC:     <linux-pm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
        David Collins <quic_collinsd@...cinc.com>,
        Subbaraman Narayanamurthy <quic_subbaram@...cinc.com>,
        Manaf Meethalavalappu Pallikunhi <quic_manafm@...cinc.com>
Subject: [PATCH] power_supply: Register cooling device outside of probe

Registering the cooling device from the probe can result in the
execution of get_property() function before it gets initialized.

To avoid this, register the cooling device from a workqueue
instead of registering in the probe.

Signed-off-by: Manaf Meethalavalappu Pallikunhi <quic_manafm@...cinc.com>
---
 drivers/power/supply/power_supply_core.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/power/supply/power_supply_core.c b/drivers/power/supply/power_supply_core.c
index 10a357a..c306b9d 100644
--- a/drivers/power/supply/power_supply_core.c
+++ b/drivers/power/supply/power_supply_core.c
@@ -132,6 +132,7 @@ void power_supply_changed(struct power_supply *psy)
 }
 EXPORT_SYMBOL_GPL(power_supply_changed);
 
+static int psy_register_cooler(struct device *dev, struct power_supply *psy);
 /*
  * Notify that power supply was registered after parent finished the probing.
  *
@@ -139,6 +140,8 @@ EXPORT_SYMBOL_GPL(power_supply_changed);
  * calling power_supply_changed() directly from power_supply_register()
  * would lead to execution of get_property() function provided by the driver
  * too early - before the probe ends.
+ * Also, registering cooling device from the probe will execute the
+ * get_property() function. So register the cooling device after the probe.
  *
  * Avoid that by waiting on parent's mutex.
  */
@@ -156,6 +159,7 @@ static void power_supply_deferred_register_work(struct work_struct *work)
 	}
 
 	power_supply_changed(psy);
+	psy_register_cooler(psy->dev.parent, psy);
 
 	if (psy->dev.parent)
 		mutex_unlock(&psy->dev.parent->mutex);
@@ -1257,10 +1261,6 @@ __power_supply_register(struct device *parent,
 	if (rc)
 		goto register_thermal_failed;
 
-	rc = psy_register_cooler(psy);
-	if (rc)
-		goto register_cooler_failed;
-
 	rc = power_supply_create_triggers(psy);
 	if (rc)
 		goto create_triggers_failed;
@@ -1290,8 +1290,6 @@ __power_supply_register(struct device *parent,
 add_hwmon_sysfs_failed:
 	power_supply_remove_triggers(psy);
 create_triggers_failed:
-	psy_unregister_cooler(psy);
-register_cooler_failed:
 	psy_unregister_thermal(psy);
 register_thermal_failed:
 	device_del(dev);
-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum,
a Linux Foundation Collaborative Project