diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 2e6310b8eab7..802b082e216d 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig
@@ -348,6 +348,7 @@ config ARCH_FLATMEM_ENABLE
 config ARCH_SPARSEMEM_ENABLE
 	def_bool y
 	depends on ARCH_DISCONTIGMEM_ENABLE
+	select SPARSEMEM_VMEMMAP_ENABLE
 
 config ARCH_DISCONTIGMEM_DEFAULT
 	def_bool y if (IA64_SGI_SN2 || IA64_GENERIC || IA64_HP_ZX1 || IA64_HP_ZX1_SWIOTLB)
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
index 0d34585058c8..5628067a74d2 100644
--- a/arch/ia64/mm/discontig.c
+++ b/arch/ia64/mm/discontig.c
@@ -715,3 +715,11 @@ void arch_refresh_nodedata(int update_node, pg_data_t *update_pgdat)
 	scatter_node_data();
 }
 #endif
+
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+int __meminit vmemmap_populate(struct page *start_page,
+						unsigned long size, int node)
+{
+	return vmemmap_populate_basepages(start_page, size, node);
+}
+#endif
diff --git a/include/asm-ia64/pgtable.h b/include/asm-ia64/pgtable.h
index de6d01e24dd0..6b4216edbb9c 100644
--- a/include/asm-ia64/pgtable.h
+++ b/include/asm-ia64/pgtable.h
@@ -236,8 +236,14 @@ ia64_phys_addr_valid (unsigned long addr)
 # define VMALLOC_END		vmalloc_end
   extern unsigned long vmalloc_end;
 #else
+#if defined(CONFIG_SPARSEMEM) && defined(CONFIG_SPARSEMEM_VMEMMAP)
+/* SPARSEMEM_VMEMMAP uses half of vmalloc... */
+# define VMALLOC_END		(RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 10)))
+# define vmemmap		((struct page *)VMALLOC_END)
+#else
 # define VMALLOC_END		(RGN_BASE(RGN_GATE) + (1UL << (4*PAGE_SHIFT - 9)))
 #endif
+#endif
 
 /* fs/proc/kcore.c */
 #define	kc_vaddr_to_offset(v) ((v) - RGN_BASE(RGN_GATE))