From mboxrd@z Thu Jan 1 00:00:00 1970 From: Aaron Lu Subject: Re: [PATCH] ACPI / video: Do not bind to device objects with a driver or scan handler Date: Sun, 09 Jun 2013 08:33:51 +0800 Message-ID: <51B3CD6F.7040606@intel.com> References: <8441239.yeE1QYIOsS@vostro.rjw.lan> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from mga02.intel.com ([134.134.136.20]:14155 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752909Ab3FIAd1 (ORCPT ); Sat, 8 Jun 2013 20:33:27 -0400 In-Reply-To: <8441239.yeE1QYIOsS@vostro.rjw.lan> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: "Rafael J. Wysocki" Cc: ACPI Devel Maling List , LKML On 06/08/2013 10:14 PM, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki > > With the introduction of ACPI scan handlers, ACPI device objects > with an ACPI scan handler attached to them must not be bound to > an ACPI driver any more. Unfortunately, however, the ACPI video > driver attempts to do just that if there is a _ROM ACPI control > method defined under a device object with an ACPI scan handler. > > Prevent that from happening by making the video driver's "add" > routine check if the device object already has a driver or > ACPI scan handler attached to it and return an error code in > that case. That is not sufficient, though, because > acpi_bus_driver_init() would then clear the device object's > driver_data that may be set by the scan handler attached to it, > so for the fix to work acpi_bus_driver_init() has to be modified > to leave driver_data as is on errors. Reviewed-by: Aaron Lu Thanks, Aaron > > References: https://bugzilla.kernel.org/show_bug.cgi?id=58091 > Reported-and-bisected-by: Dmitry S. Demin > Reported-and-tested-by: Jason Cassell > Tracked-down-by: Aaron Lu > Cc: 3.9+ > Signed-off-by: Rafael J. Wysocki > --- > drivers/acpi/scan.c | 5 +---- > drivers/acpi/video.c | 3 +++ > 2 files changed, 4 insertions(+), 4 deletions(-) > > Index: linux-pm/drivers/acpi/video.c > =================================================================== > --- linux-pm.orig/drivers/acpi/video.c > +++ linux-pm/drivers/acpi/video.c > @@ -1722,6 +1722,9 @@ static int acpi_video_bus_add(struct acp > int error; > acpi_status status; > > + if (device->handler || device->driver) > + return -EINVAL; > + > status = acpi_walk_namespace(ACPI_TYPE_DEVICE, > device->parent->handle, 1, > acpi_video_bus_match, NULL, > Index: linux-pm/drivers/acpi/scan.c > =================================================================== > --- linux-pm.orig/drivers/acpi/scan.c > +++ linux-pm/drivers/acpi/scan.c > @@ -1133,11 +1133,8 @@ acpi_bus_driver_init(struct acpi_device > return -ENOSYS; > > result = driver->ops.add(device); > - if (result) { > - device->driver = NULL; > - device->driver_data = NULL; > + if (result) > return result; > - } > > device->driver = driver; > >