From 9f29ab11ddbfc12db54df5a66dab22b39ad94e8e Mon Sep 17 00:00:00 2001 From: Aaron Lu Date: Tue, 4 Jun 2013 23:02:58 +0200 Subject: ACPI / scan: do not match drivers against objects having scan handlers 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-by: Jason Cassell Reported-and-bisected-by: Dmitry S. Demin Cc: 3.9+ Signed-off-by: Aaron Lu Signed-off-by: Rafael J. Wysocki --- drivers/acpi/scan.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 44225cb15f3a..90c5759e1355 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -740,6 +740,10 @@ 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); } -- cgit v1.2.3 From ea7f665612fcc73da6b7698f468cd5fc03a30d47 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Sat, 8 Jun 2013 02:55:07 +0200 Subject: Revert "ACPI / scan: do not match drivers against objects having scan handlers" Commit 9f29ab11ddbf ("ACPI / scan: do not match drivers against objects having scan handlers") introduced a boot regression on Tony's ia64 HP rx2600. Tony says: "It panics with the message: Kernel panic - not syncing: Unable to find SBA IOMMU: Try a generic or DIG kernel [...] my problem comes from arch/ia64/hp/common/sba_iommu.c where the code in sba_init() says: acpi_bus_register_driver(&acpi_sba_ioc_driver); if (!ioc_list) { but because of this change we never managed to call ioc_init() so ioc_list doesn't get set up, and we die." Revert it to avoid this breakage and we'll fix the problem it attempted to address later. Reported-by: Tony Luck Cc: 3.9+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Linus Torvalds --- drivers/acpi/scan.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 90c5759e1355..44225cb15f3a 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -740,10 +740,6 @@ 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); } -- cgit v1.2.3 From 8c9b7a7b2fc2750af418ddc28e707c42e78aa0bf Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 10 Jun 2013 13:00:29 +0200 Subject: ACPI / video: Do not bind to device objects with a scan handler With the introduction of ACPI scan handlers, ACPI device objects with an ACPI scan handler attached to them must not be bound to by ACPI drivers 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 an 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 its scan handler, so for the fix to work acpi_bus_driver_init() has to be modified to leave driver_data as is on errors. References: https://bugzilla.kernel.org/show_bug.cgi?id=58091 Bisected-and-tested-by: Dmitry S. Demin Reported-and-tested-by: Jason Cassell Tracked-down-by: Aaron Lu Cc: 3.9+ Signed-off-by: Rafael J. Wysocki Reviewed-by: Aaron Lu --- drivers/acpi/scan.c | 5 +---- drivers/acpi/video.c | 3 +++ 2 files changed, 4 insertions(+), 4 deletions(-) (limited to 'drivers/acpi/scan.c') diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c index 44225cb15f3a..b14ac46948c9 100644 --- a/drivers/acpi/scan.c +++ b/drivers/acpi/scan.c @@ -1017,11 +1017,8 @@ acpi_bus_driver_init(struct acpi_device *device, struct acpi_driver *driver) return -ENOSYS; result = driver->ops.add(device); - if (result) { - device->driver = NULL; - device->driver_data = NULL; + if (result) return result; - } device->driver = driver; diff --git a/drivers/acpi/video.c b/drivers/acpi/video.c index 5d7075d25700..440eadf2d32c 100644 --- a/drivers/acpi/video.c +++ b/drivers/acpi/video.c @@ -1722,6 +1722,9 @@ static int acpi_video_bus_add(struct acpi_device *device) int error; acpi_status status; + if (device->handler) + return -EINVAL; + status = acpi_walk_namespace(ACPI_TYPE_DEVICE, device->parent->handle, 1, acpi_video_bus_match, NULL, -- cgit v1.2.3