ACPI / init: Fix the ordering of acpi_reserve_resources()

commit b9a5e5e1 upstream.

Since acpi_reserve_resources() is defined as a device_initcall(),
there's no guarantee that it will be executed in the right order
with respect to the rest of the ACPI initialization code.  On some
systems this leads to breakage if, for example, the address range
that should be reserved for the ACPI fixed registers is given to
the PCI host bridge instead if the race is won by the wrong code
path.

Fix this by turning acpi_reserve_resources() into a void function
and calling it directly from within the ACPI initialization sequence.
Reported-and-tested-by: George McCollister <george.mccollister@gmail.com>
Link: http://marc.info/?t=143092384600002&r=1&w=2Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

drivers/acpi/osl.c

@@ -172,7 +172,7 @@ static void __init acpi_request_region (struct acpi_generic_address *gas,
 		request_mem_region(addr, length, desc);
 }
 
-static int __init acpi_reserve_resources(void)
+static void __init acpi_reserve_resources(void)
 {
 	acpi_request_region(&acpi_gbl_FADT.xpm1a_event_block, acpi_gbl_FADT.pm1_event_length,
 		"ACPI PM1a_EVT_BLK");
@@ -201,10 +201,7 @@ static int __init acpi_reserve_resources(void)
 	if (!(acpi_gbl_FADT.gpe1_block_length & 0x1))
 		acpi_request_region(&acpi_gbl_FADT.xgpe1_block,
 			       acpi_gbl_FADT.gpe1_block_length, "ACPI GPE1_BLK");
-
-	return 0;
 }
-device_initcall(acpi_reserve_resources);
 
 void acpi_os_printf(const char *fmt, ...)
 {
@@ -1827,6 +1824,7 @@ acpi_status __init acpi_os_initialize(void)
 
 acpi_status __init acpi_os_initialize1(void)
 {
+	acpi_reserve_resources();
 	kacpid_wq = alloc_workqueue("kacpid", 0, 1);
 	kacpi_notify_wq = alloc_workqueue("kacpi_notify", 0, 1);
 	kacpi_hotplug_wq = alloc_ordered_workqueue("kacpi_hotplug", 0);