[PATCH] ACPI / scan: Clear match_driver flag in acpi_bus_trim()

["Rafael J. Wysocki" <rjw@rjwysocki.net>]

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Drivers should not bind to struct acpi_device objects that
acpi_bus_trim() has been called for, so make that function
clear flags.match_driver for those objects.

If that is not done, an ACPI driver may theoretically try to operate
a device that is not physically present.

Fixes: 202317a573b2 (ACPI / scan: Add acpi_device objects for all device nodes in the namespace)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/acpi/scan.c |    1 +
 1 file changed, 1 insertion(+)

Index: linux-pm/drivers/acpi/scan.c
===================================================================
--- linux-pm.orig/drivers/acpi/scan.c
+++ linux-pm/drivers/acpi/scan.c
@@ -2106,6 +2106,7 @@ void acpi_bus_trim(struct acpi_device *a
 	list_for_each_entry_reverse(child, &adev->children, node)
 		acpi_bus_trim(child);
 
+	adev->flags.match_driver = false;
 	if (handler) {
 		if (handler->detach)
 			handler->detach(adev);