[ 67/73] ACPI/AC: prevent OOPS on some boxes due to missing checkpower_supply_register() return value check

From: Ben Hutchings
Date: Tue Jul 31 2012 - 01:04:05 EST


3.2-stable review patch. If anyone has any objections, please let me know.

------------------

From: Lan Tianyu <tianyu.lan@xxxxxxxxx>

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@xxxxxxxxx>
Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/acpi/ac.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/ac.c b/drivers/acpi/ac.c
index 6512b20..d1fcbc0 100644
--- 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),


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/