diff --git a/mm/Kconfig b/mm/Kconfig
index a7609cb..b067306 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -112,6 +112,19 @@
 	def_bool y
 	depends on SPARSEMEM && !SPARSEMEM_STATIC
 
+#
+# SPARSEMEM_VMEMMAP uses a virtually mapped mem_map to optimise pfn_to_page
+# and page_to_pfn.  The most efficient option where kernel virtual space is
+# not under pressure.
+#
+config SPARSEMEM_VMEMMAP_ENABLE
+	def_bool n
+
+config SPARSEMEM_VMEMMAP
+	bool
+	depends on SPARSEMEM
+	default y if (SPARSEMEM_VMEMMAP_ENABLE)
+
 # eventually, we can have this option just 'select SPARSEMEM'
 config MEMORY_HOTPLUG
 	bool "Allow for memory hot-add"