diff mbox series

[linux,dev-5.15,2/2] hwmon: (occ) Lock mutex in shutdown to prevent race with occ_active

Message ID 20220607190118.5078-3-eajames@linux.ibm.com
State New
Headers show
Series hwmon: (occ) Delay hwmon registration until user request | expand

Commit Message

Eddie James June 7, 2022, 7:01 p.m. UTC 
Unbinding the driver or removing the parent device at the same time
as using the OCC active sysfs file can cause the driver to unregister
the hwmon device twice. Prevent this by locking the occ mutex in the
shutdown function.

Signed-off-by: Eddie James <eajames@linux.ibm.com>
Link: https://lore.kernel.org/r/20220606185455.21126-1-eajames@linux.ibm.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
---
 drivers/hwmon/occ/common.c | 5 +++++
 1 file changed, 5 insertions(+)
diff mbox series

Patch

diff --git a/drivers/hwmon/occ/common.c b/drivers/hwmon/occ/common.c
index d78f4bebc718..ea070b91e5b9 100644
--- a/drivers/hwmon/occ/common.c
+++ b/drivers/hwmon/occ/common.c
@@ -1228,10 +1228,15 @@  EXPORT_SYMBOL_GPL(occ_setup);
 
 void occ_shutdown(struct occ *occ)
 {
+	mutex_lock(&occ->lock);
+
 	occ_shutdown_sysfs(occ);
 
 	if (occ->hwmon)
 		hwmon_device_unregister(occ->hwmon);
+	occ->hwmon = NULL;
+
+	mutex_unlock(&occ->lock);
 }
 EXPORT_SYMBOL_GPL(occ_shutdown);