With the introduction of ACPI scan handlers, an ACPI device object with an ACPI scan handler attached to it must not be bound to an ACPI driver any more. Therefore it doesn't make sense to match those ACPI device objects against a newly registered ACPI driver in acpi_bus_match(), so make that function return 0 if the device object passed to it has an ACPI scan handler attached. This also addresses a regression related to a broken ACPI table in the BIOS, where it has defined a _ROM method under the PCI root bridge object. This causes the video module to treat that object as a display controller device (since only display devices are supposed to have a _ROM method defined according to the ACPI spec). As a result, the ACPI video driver binds to the PCI root bridge object and overwrites the previously assigned driver_data field of it, causing subsequent calls to acpi_get_pci_dev() to fail. [rjw: Subject and changelog] References: https://bugzilla.kernel.org/show_bug.cgi?id=58091 Reported-and-tested-by: Jason Cassell <bluesloth600@xxxxxxxxx> Reported-bisected-and-tested-by: Dmitry S. Demin <dmitryy.demin@xxxxxxxxx> Cc: 3.9+ <stable@xxxxxxxxxx> Signed-off-by: Aaron Lu <aaron.lu@xxxxxxxxx> --- v2: Remove WARN_ON as it would cause unnecessary warnings for devices that already have drivers bound. drivers/acpi/scan.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 5e7e991..67ce501 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -553,6 +553,10 @@ static int acpi_bus_match(struct device *dev, struct device_driver *drv) struct acpi_device *acpi_dev = to_acpi_device(dev); struct acpi_driver *acpi_drv = to_acpi_driver(drv); + /* Skip ACPI device objects with scan handlers attached. */ + if (acpi_dev->handler) + return 0; + return acpi_dev->flags.match_driver && !acpi_match_device_ids(acpi_dev, acpi_drv->ids); } -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
