ACPI / scan: Start matching drivers after trying scan handlers

ACPI scan handlers should always be attached to struct acpi_device
objects before any ACPI drivers, but there is a window during which
a driver may be attached to a struct acpi_device before checking if
there is a matching scan handler.  Namely, that will happen if an
ACPI driver module is loaded during acpi_bus_scan() right after
the first namespace walk is complete and before the given device
is processed by the second namespace walk.

To prevent that from happening, set the match_driver flags of
struct acpi_device objects right before running device_attach()
for them in acpi_bus_device_attach().

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
This commit is contained in:
Rafael J. Wysocki 2013-11-07 01:41:01 +01:00
parent 71bba8fafa
commit 6931007cc9

View File

@ -1677,7 +1677,6 @@ void acpi_init_device_object(struct acpi_device *device, acpi_handle handle,
void acpi_device_add_finalize(struct acpi_device *device)
{
device->flags.match_driver = true;
dev_set_uevent_suppress(&device->dev, false);
kobject_uevent(&device->dev.kobj, KOBJ_ADD);
}
@ -1916,8 +1915,12 @@ static acpi_status acpi_bus_device_attach(acpi_handle handle, u32 lvl_not_used,
return AE_OK;
ret = acpi_scan_attach_handler(device);
if (ret)
return ret > 0 ? AE_OK : AE_CTRL_DEPTH;
if (ret < 0)
return AE_CTRL_DEPTH;
device->flags.match_driver = true;
if (ret > 0)
return AE_OK;
ret = device_attach(&device->dev);
return ret >= 0 ? AE_OK : AE_CTRL_DEPTH;