Revert "ACPI / scan: do not match drivers against objects having scan handlers"

commit ea7f665612fcc73da6b7698f468cd5fc03a30d47 upstream.

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 <tony.luck@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c
index 2855aaee89862a198e2183ed36baf2e36ca7930b..5e7e991717d76f97981fcff3d0a221879b47fcea 100644 (file)
--- a/drivers/acpi/scan.c
+++ b/drivers/acpi/scan.c
@@ -553,10 +553,6 @@ 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);
 }