mm: fix memory hotplug oops from ZONE_MOVABLE changes.

zone_movable_pfn is presently marked as __initdata and referenced from
adjust_zone_range_for_zone_movable(), which in turn is referenced by
zone_spanned_pages_in_node().  Both of these are __meminit annotated.  When
memory hotplug is enabled, this will oops on a hot-add, due to
zone_movable_pfn having been freed.

__meminitdata annotation gives the desired behaviour.

This will only impact platforms that enable both memory hotplug
and ARCH_POPULATES_NODE_MAP.
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>
Acked-by: NMel Gorman <mel@csn.ul.ie>
Acked-by: NKAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

mm/page_alloc.c

@@ -138,7 +138,7 @@ static unsigned long __meminitdata dma_reserve;
 #endif /* CONFIG_MEMORY_HOTPLUG_RESERVE */
   unsigned long __initdata required_kernelcore;
   unsigned long __initdata required_movablecore;
-  unsigned long __initdata zone_movable_pfn[MAX_NUMNODES];
+  unsigned long __meminitdata zone_movable_pfn[MAX_NUMNODES];
 
   /* movable_zone is the "real" zone pages in ZONE_MOVABLE are taken from */
   int movable_zone;