From: Badari Pulavarty <pbadari@us.ibm.com>

walk_memory_resource() should return failure, if it can't find the memory
region in the /proc/iomem.  Otherwise, offline_pages() would end up
isolating pages wrongly.

Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---


diff -puN kernel/resource.c~memory-unplug-v7-memory-hotplug-cleanup-fix kernel/resource.c
--- a/kernel/resource.c~memory-unplug-v7-memory-hotplug-cleanup-fix
+++ a/kernel/resource.c
@@ -274,7 +274,7 @@ walk_memory_resource(unsigned long start
 	struct resource res;
 	unsigned long pfn, len;
 	u64 orig_end;
-	int ret;
+	int ret = -1;
 	res.start = (u64) start_pfn << PAGE_SHIFT;
 	res.end = ((u64)(start_pfn + nr_pages) << PAGE_SHIFT) - 1;
 	res.flags = IORESOURCE_MEM;
_