On Thursday, June 06, 2013 10:54:52 AM Aaron Lu wrote: > 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> I've applied this one already. Thanks, Rafael > --- > 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); > } -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- 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
