ACPI / scan: Do not try to attach scan handlers to devices having them
authorRafael J. Wysocki <rafael.j.wysocki@intel.com>
Fri, 12 Jul 2013 11:45:59 +0000 (13:45 +0200)
committerRafael J. Wysocki <rafael.j.wysocki@intel.com>
Sun, 14 Jul 2013 23:26:18 +0000 (01:26 +0200)
commit3a391a39593b48341f0908511590a6c0e55cc069
tree010d442c1c624fa6d9e7d1ba46c2ff2b6331f722
parentad81f0545ef01ea651886dddac4bef6cec930092
ACPI / scan: Do not try to attach scan handlers to devices having them

In acpi_bus_device_attach(), if there is an ACPI device object
for the given handle and that device object has a scan handler
attached to it already, there's nothing more to do for that handle.
Moreover, if acpi_scan_attach_handler() is called then, it may
execute the .attach() callback of the ACPI scan handler already
attached to the device object and that may lead to interesting
breakage.

For this reason, make acpi_bus_device_attach() return success
immediately when the handle's device object has a scan handler
attached to it.

Reported-by: Toshi Kani <toshi.kani@hp.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
Cc: 3.10+ <stable@vger.kernel.org>
drivers/acpi/scan.c