ACPI/AC: prevent OOPS on some boxes due to missing check power_supply_register()...

commit f197ac13f6eeb351b31250b9ab7d0da17434ea36 upstream.

In the ac.c, power_supply_register()'s return value is not checked.

As a result, the driver's add() ops may return success
even though the device failed to initialize.

For example, some BIOS may describe two ACADs in the same DSDT.
The second ACAD device will fail to register,
but ACPI driver's add() ops returns sucessfully.
The ACPI device will receive ACPI notification and cause OOPS.

https://bugzilla.redhat.com/show_bug.cgi?id=772730

Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index 6512b20aeccdce0184a6a5c524af85c6f7f6db91..d1fcbc0f6cbc6d93e3523f913822d68fda0b8ad2 100644 (file)
--- a/drivers/acpi/ac.c
+++ b/drivers/acpi/ac.c
@@ -292,7 +292,9 @@ static int acpi_ac_add(struct acpi_device *device)
        ac->charger.properties = ac_props;
        ac->charger.num_properties = ARRAY_SIZE(ac_props);
        ac->charger.get_property = get_ac_property;
-       power_supply_register(&ac->device->dev, &ac->charger);
+       result = power_supply_register(&ac->device->dev, &ac->charger);
+       if (result)
+               goto end;
 
        printk(KERN_INFO PREFIX "%s [%s] (%s)\n",
               acpi_device_name(device), acpi_device_bid(device),