x86-64: fix combining of regions in init_memory_mapping()

When nr_range gets decremented, the same slot must be considered for
coalescing with its new successor again.

The issue is apparently pretty benign to native code, but surfaces as a
boot time crash in our forward ported Xen tree (where the page table
setup overall works differently than in native).

Signed-off-by: Jan Beulich <jbeulich@novell.com>
Acked-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 1 insertions, 1 deletions

diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 7c8bb46e83e4..b8e461d49412 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -746,7 +746,7 @@ unsigned long __init_refok init_memory_mapping(unsigned long start,
                 old_start = mr[i].start;
                 memmove(&mr[i], &mr[i+1],
                          (nr_range - 1 - i) * sizeof (struct map_range));
-                mr[i].start = old_start;
+                mr[i--].start = old_start;
                 nr_range--;
         }