xl migrate --debug can segfault because pagebuf->pfn_types[pfn] is
used in a print statement instead of pfn_type[pfn] 

--- xen-4.5.0-rc1/tools/libxc/xc_domain_restore.c.orig	2014-10-24 15:22:40.000000000 +0100
+++ xen-4.5.0-rc1/tools/libxc/xc_domain_restore.c	2014-11-25 21:01:16.604081467 +0000
@@ -1404,7 +1404,7 @@
                 int v;
 
                 DPRINTF("************** pfn=%lx type=%lx gotcs=%08lx "
-                        "actualcs=%08lx\n", pfn, pagebuf->pfn_types[pfn],
+                        "actualcs=%08lx\n", pfn, pfn_type[pfn],
                         csum_page(region_base + i * PAGE_SIZE),
                         csum_page(buf));