From: Jan Beulich <jbeulich@novell.com>
Date: Fri, 12 Sep 2008 14:43:04 +0000 (+0100)
Subject: x86-64: fix combining of regions in init_memory_mapping()
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=5e72d9e4850c91b6a0f06fa803f7393b55a38aa8;p=linux-beck.git

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>
---

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--;
 	}