Index: linux-3.5-rc6/include/linux/mm.h
===================================================================
--- linux-3.5-rc6.orig/include/linux/mm.h	2012-07-19 15:07:48.836986796 +0900
+++ linux-3.5-rc6/include/linux/mm.h	2012-07-19 15:07:59.101858469 +0900
@@ -1588,6 +1588,8 @@ int vmemmap_populate(struct page *start_
 void vmemmap_populate_print_last(void);
 void register_page_bootmem_memmap(unsigned long section_nr, struct page *map,
 				  unsigned long size);
+void vmemmap_kfree(struct page *memmpa, unsigned long nr_pages);
+void vmemmap_free_bootmem(struct page *memmpa, unsigned long nr_pages);
 
 enum mf_flags {
 	MF_COUNT_INCREASED = 1 << 0,
Index: linux-3.5-rc6/mm/sparse.c
===================================================================
--- linux-3.5-rc6.orig/mm/sparse.c	2012-07-19 11:57:09.065797011 +0900
+++ linux-3.5-rc6/mm/sparse.c	2012-07-19 15:07:59.114858306 +0900
@@ -614,12 +614,13 @@ static inline struct page *kmalloc_secti
 	/* This will make the necessary allocations eventually. */
 	return sparse_mem_map_populate(pnum, nid);
 }
-static void __kfree_section_memmap(struct page *memmap, unsigned long nr_pages)
+static void __kfree_section_memmap(struct page *page, unsigned long nr_pages)
 {
-	return; /* XXX: Not implemented yet */
+	vmemmap_kfree(page, nr_pages);
 }
 static void free_map_bootmem(struct page *page, unsigned long nr_pages)
 {
+	vmemmap_free_bootmem(page, nr_pages);
 }
 #else
 static struct page *__kmalloc_section_memmap(unsigned long nr_pages)
Index: linux-3.5-rc6/arch/x86/mm/init_64.c
===================================================================
--- linux-3.5-rc6.orig/arch/x86/mm/init_64.c	2012-07-19 15:07:48.898986022 +0900
+++ linux-3.5-rc6/arch/x86/mm/init_64.c	2012-07-19 15:14:05.870273270 +0900
@@ -978,6 +978,127 @@ vmemmap_populate(struct page *start_page
 	return 0;
 }
 
+#define PAGE_INUSE 0xFD
+
+unsigned long find_and_clear_pte_page(unsigned long addr, unsigned long end,
+			    struct page **pp, int *page_size)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	void *page_addr;
+	unsigned long next;
+
+	*pp = NULL;
+
+	pgd = pgd_offset_k(addr);
+	if (pgd_none(*pgd))
+		return pgd_addr_end(addr, end);
+
+	pud = pud_offset(pgd, addr);
+	if (pud_none(*pud))
+		return pud_addr_end(addr, end);
+
+	if (!cpu_has_pse) {
+		next = (addr + PAGE_SIZE) & PAGE_MASK;
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		pte = pte_offset_kernel(pmd, addr);
+		if (pte_none(*pte))
+			return next;
+
+		*page_size = PAGE_SIZE;
+		*pp = pte_page(*pte);
+	} else {
+		next = pmd_addr_end(addr, end);
+
+		pmd = pmd_offset(pud, addr);
+		if (pmd_none(*pmd))
+			return next;
+
+		*page_size = PMD_SIZE;
+		*pp = pmd_page(*pmd);
+	}
+
+	/*
+	 * Removed page structs are filled with 0xFD.
+	 */
+	memset((void *)addr, PAGE_INUSE, next - addr);
+
+	page_addr = page_address(*pp);
+
+	/*
+	 * Check the page is filled with 0xFD or not.
+	 * memchr_inv() returns the address. In this case, we cannot
+	 * clear PTE/PUD entry, since the page is used by other.
+	 * So we cannot also free the page.
+	 *
+	 * memchr_inv() returns NULL. In this case, we can clear
+	 * PTE/PUD entry, since the page is not used by other.
+	 * So we can also free the page.
+	 */
+	if (memchr_inv(page_addr, PAGE_INUSE, *page_size)) {
+		*pp = NULL;
+		return next;
+	}
+
+	if (!cpu_has_pse)
+		pte_clear(&init_mm, addr, pte);
+	else
+		pmd_clear(pmd);
+
+	return next;
+}
+
+void vmemmap_kfree(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	struct page *page;
+	int page_size;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		page_size = 0;
+		next = find_and_clear_pte_page(addr, end, &page, &page_size);
+		if (!page)
+			continue;
+
+		free_pages((unsigned long)page_address(page),
+			    get_order(page_size));
+		__flush_tlb_one((unsigned long)page_address(page));
+	}
+
+}
+
+void vmemmap_free_bootmem(struct page *memmap, unsigned long nr_pages)
+{
+	unsigned long addr = (unsigned long)memmap;
+	unsigned long end = (unsigned long)(memmap + nr_pages);
+	unsigned long next;
+	struct page *page;
+	int page_size;
+	unsigned long magic;
+
+	for (; addr < end; addr = next) {
+		page = NULL;
+		page_size = 0;
+		next = find_and_clear_pte_page(addr, end, &page, &page_size);
+		if (!page)
+			continue;
+
+		magic = (unsigned long) page->lru.next;
+		if (magic == SECTION_INFO)
+			put_page_bootmem(page);
+		flush_tlb_kernel_range(addr, end);
+	}
+
+}
+
 void register_page_bootmem_memmap(unsigned long section_nr,
 				  struct page *start_page, unsigned long size)
 {
Index: linux-3.5-rc6/mm/memory_hotplug.c
===================================================================
--- linux-3.5-rc6.orig/mm/memory_hotplug.c	2012-07-19 15:07:48.815987060 +0900
+++ linux-3.5-rc6/mm/memory_hotplug.c	2012-07-19 15:12:27.536502452 +0900
@@ -300,19 +300,6 @@ static int __meminit __add_section(int n
 	return register_new_memory(nid, __pfn_to_section(phys_start_pfn));
 }
 
-#ifdef CONFIG_SPARSEMEM_VMEMMAP
-static int __remove_section(struct zone *zone, struct mem_section *ms)
-{
-	int ret = -EINVAL;
-
-	if (!valid_section(ms))
-		return ret;
-
-	ret = unregister_memory_section(ms);
-
-	return ret;
-}
-#else
 static int __remove_section(struct zone *zone, struct mem_section *ms)
 {
 	unsigned long flags;
@@ -329,9 +316,9 @@ static int __remove_section(struct zone 
 	pgdat_resize_lock(pgdat, &flags);
 	sparse_remove_one_section(zone, ms);
 	pgdat_resize_unlock(pgdat, &flags);
-	return 0;
+
+	return ret;
 }
-#endif
 
 /*
  * Reasonably generic function for adding memory.  It is
