Index: linux-2.6.21-rc5-mm4/mm/sparse.c
===================================================================
--- linux-2.6.21-rc5-mm4.orig/mm/sparse.c	2007-04-04 12:21:31.000000000 -0700
+++ linux-2.6.21-rc5-mm4/mm/sparse.c	2007-04-04 15:29:56.000000000 -0700
@@ -271,9 +271,24 @@
 
 #ifndef CONFIG_ARCH_POPULATES_VIRTUAL_MEMMAP
 
+static int vmemmap_verify(pte_t *pte, int node,
+		unsigned long start, unsigned long end)
+{
+	unsigned long pfn = pte_pfn(*pte);
+	int actual_node = early_pfn_to_nid(pfn);
+
+	if (actual_node != node)
+		printk(KERN_WARNING "  [%lx-%lx] offnode page_structs\n",
+			start, end - 1);
+	return 0;
+}
+
 #ifndef CONFIG_ARCH_SUPPORTS_PMD_MAPPING
 
-static int vmemmap_pte_setup(pte_t *pte,  int node)
+#define VIRTUAL_MEMMAP_SIZE PAGE_SIZE
+#define VIRTUAL_MEMMAP_MASK PAGE_MASK
+
+static int vmemmap_pte_setup(pte_t *pte,  int node, unsigned long addr)
 {
 	void *block;
 	pte_t entry;
@@ -284,6 +299,9 @@
 
 	entry = pfn_pte(__pa(block) >> PAGE_SHIFT, PAGE_KERNEL);
 	set_pte(pte, entry);
+	addr &= ~(PAGE_SIZE - 1);
+	printk(KERN_INFO " [%lx-%lx]->%p on node %d\n",
+		addr, addr + PAGE_SIZE -1, block, node);
 	return 0;
 }
 
@@ -296,7 +314,10 @@
 	for (pte = pte_offset_map(pmd, addr); addr < end && !error;
 			pte++, addr += PAGE_SIZE)
   		if (pte_none(*pte))
-			error =	vmemmap_pte_setup(pte, node);
+			error =	vmemmap_pte_setup(pte, node, addr);
+		else
+			error = vmemmap_verify(pte, node,
+				addr + PAGE_SIZE, end);
 	return error;
 }
 
@@ -313,13 +334,16 @@
 
 #else /* CONFIG_ARCH_SUPPORTS_PMD_MAPPING */
 
+#define VIRTUAL_MEMMAP_SIZE PMD_SIZE
+#define VIRTUAL_MEMMAP_MASK PMD_MASK
+
 static int vmemmap_pop_pte(pmd_t *pmd, unsigned long addr,
 				unsigned long end, int node)
 {
 	return 0;
 }
 
-static int vmemmap_pmd_setup(pmd_t *pmd, int node)
+static int vmemmap_pmd_setup(pmd_t *pmd, int node, unsigned long addr)
 {
 	void *block;
 	pte_t entry;
@@ -331,6 +355,9 @@
 	entry = pfn_pte(__pa(block) >> PAGE_SHIFT, PAGE_KERNEL);
 	mk_pte_huge(entry);
 	set_pmd(pmd, __pmd(pte_val(entry)));
+	addr &= ~(PMD_SIZE - 1);
+	printk(KERN_INFO " [%lx-%lx]->%p on node %d\n",
+		addr, addr + PMD_SIZE - 1, block, node);
 	return 0;
 }
 
@@ -342,15 +369,17 @@
 	pmd_t *pmd;
 	int error = 0;
 
-	end = pmd_addr_end(addr, end);
-
 	for (pmd = pmd_offset(pud, addr); addr < end && !error;
 			pmd++, addr += PMD_SIZE) {
   		if (pmd_none(*pmd))
-			error = vmemmap_pmd_setup(pmd, node);
+			error = vmemmap_pmd_setup(pmd, node, addr);
+		else
+			error = vmemmap_verify((pte_t *)pmd, node,
+				pmd_addr_end(addr, end), end);
 
 		if (!error)
-			error = vmemmap_pop_pte(pmd, addr, end, node);
+			error = vmemmap_pop_pte(pmd, addr,
+				pmd_addr_end(addr, end), node);
 	}
 	return error;
 }
@@ -361,7 +390,6 @@
 	pud_t *pud;
 	int error = 0;
 
-	end = pud_addr_end(addr, end);
 	for (pud = pud_offset(pgd, addr); addr < end && !error;
 				pud++, addr += PUD_SIZE) {
 
@@ -374,7 +402,8 @@
 
 			pud_populate(&init_mm, pud, p);
 		}
-		error = vmemmap_pop_pmd(pud, addr, end, node);
+		error = vmemmap_pop_pmd(pud, addr,
+			pud_addr_end(addr, end), node);
 	}
 	return error;
 }
@@ -383,11 +412,17 @@
 								int node)
 {
 	pgd_t *pgd;
-	unsigned long addr = (unsigned long)start_page;
-	unsigned long end = pgd_addr_end(addr,
-			(unsigned long)(start_page + nr));
+	unsigned long addr = (unsigned long)start_page & VIRTUAL_MEMMAP_MASK;
+	unsigned long end =
+		((unsigned long)(start_page + nr) & VIRTUAL_MEMMAP_MASK)
+				+ VIRTUAL_MEMMAP_SIZE;
 	int error = 0;
 
+	printk(KERN_INFO "[%lx-%lx] Virtual memory section"
+		" (%ld pages) node %d\n",
+		(unsigned long)start_page,
+		(unsigned long)(start_page + nr) - 1, nr, node);
+
 	for (pgd = pgd_offset_k(addr); addr < end && !error;
 				pgd++, addr += PGDIR_SIZE) {
 
@@ -397,7 +432,8 @@
 
 			pgd_populate(&init_mm, pgd, p);
 		}
-		error = vmemmap_pop_pud(pgd, addr, end, node);
+		error = vmemmap_pop_pud(pgd, addr,
+			pgd_addr_end(addr, end), node);
 	}
 	return error;
 }