mm: remove_memory(): fix end_pfn setting

remove_memory() calls walk_memory_range() with [start_pfn, end_pfn), where
end_pfn is exclusive in this range.  Therefore, end_pfn needs to be set to
the next page of the end address.

Signed-off-by: Toshi Kani <[email protected]>
Cc: Wen Congyang <[email protected]>
Cc: Tang Chen <[email protected]>
Cc: Kamezawa Hiroyuki <[email protected]>
Cc: KOSAKI Motohiro <[email protected]>
Cc: Jiang Liu <[email protected]>
Cc: Jianguo Wu <[email protected]>
Cc: Lai Jiangshan <[email protected]>
Cc: Wu Jianguo <[email protected]>
Cc: Yasuaki Ishimatsu <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

mm/memory_hotplug.c

@@ -1801,7 +1801,7 @@ int __ref remove_memory(int nid, u64 start, u64 size)
 	int retry = 1;
 
 	start_pfn = PFN_DOWN(start);
-	end_pfn = start_pfn + PFN_DOWN(size);
+	end_pfn = PFN_UP(start + size - 1);
 
 	/*
 	 * When CONFIG_MEMCG is on, one memory block may be used by other