platform/x86: dell-ddv: Fix taking the psy->extensions_sem lock twice

Calling power_supply_get_property() inside
dell_wmi_ddv_battery_translate() can cause a deadlock since this
function is also being called from the power supply extension code,
in which case psy->extensions_sem is already being held.

Fix this by using the new power_supply_get_property_direct() function
to ignore any power supply extensions when retrieving the battery
serial number.

Tested on a Dell Inspiron 3505.

Reported-by: Hans de Goede <hansg@kernel.org>
Fixes: 058de163a376 ("platform/x86: dell-ddv: Implement the battery matching algorithm")
Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Link: https://lore.kernel.org/r/20250627205124.250433-3-W_Armin@gmx.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

diff --git a/drivers/platform/x86/dell/dell-wmi-ddv.c b/drivers/platform/x86/dell/dell-wmi-ddv.c
index 67f3d71584037b236ce15b1962f86a250c4dd93a..62e3d060f0385c22587a67c49634d3c15e107d30 100644 (file)
--- a/drivers/platform/x86/dell/dell-wmi-ddv.c
+++ b/drivers/platform/x86/dell/dell-wmi-ddv.c
@@ -689,9 +689,13 @@ static int dell_wmi_ddv_battery_translate(struct dell_wmi_ddv_data *data,
 
        dev_dbg(&data->wdev->dev, "Translation cache miss\n");
 
-       /* Perform a translation between a ACPI battery and a battery index */
-
-       ret = power_supply_get_property(battery, POWER_SUPPLY_PROP_SERIAL_NUMBER, &val);
+       /*
+        * Perform a translation between a ACPI battery and a battery index.
+        * We have to use power_supply_get_property_direct() here because this
+        * function will also get called from the callbacks of the power supply
+        * extension.
+        */
+       ret = power_supply_get_property_direct(battery, POWER_SUPPLY_PROP_SERIAL_NUMBER, &val);
        if (ret < 0)
                return ret;