1 files changed, 35 insertions, 3 deletions

diff --git a/mm/Kconfig b/mm/Kconfig
index 5127441561b4..cd379936cac6 100644
--- a/mm/Kconfig
+++ b/mm/Kconfig
@@ -6,6 +6,7 @@ choice
         prompt "Memory model"
         depends on SELECT_MEMORY_MODEL
         default DISCONTIGMEM_MANUAL if ARCH_DISCONTIGMEM_DEFAULT
+        default SPARSEMEM_MANUAL if ARCH_SPARSEMEM_DEFAULT
         default FLATMEM_MANUAL
 
 config FLATMEM_MANUAL
@@ -17,7 +18,15 @@ config FLATMEM_MANUAL
           only have one option here: FLATMEM.  This is normal
           and a correct option.
 
-          If unsure, choose this option over any other.
+          Some users of more advanced features like NUMA and
+          memory hotplug may have different options here.
+          DISCONTIGMEM is an more mature, better tested system,
+          but is incompatible with memory hotplug and may suffer
+          decreased performance over SPARSEMEM.  If unsure between
+          "Sparse Memory" and "Discontiguous Memory", choose
+          "Discontiguous Memory".
+
+          If unsure, choose this option (Flat Memory) over any other.
 
 config DISCONTIGMEM_MANUAL
         bool "Discontigious Memory"
@@ -35,15 +44,38 @@ config DISCONTIGMEM_MANUAL
 
           If unsure, choose "Flat Memory" over this option.
 
+config SPARSEMEM_MANUAL
+        bool "Sparse Memory"
+        depends on ARCH_SPARSEMEM_ENABLE
+        help
+          This will be the only option for some systems, including
+          memory hotplug systems.  This is normal.
+
+          For many other systems, this will be an alternative to
+          "Discontigious Memory".  This option provides some potential
+          performance benefits, along with decreased code complexity,
+          but it is newer, and more experimental.
+
+          If unsure, choose "Discontiguous Memory" or "Flat Memory"
+          over this option.
+
 endchoice
 
 config DISCONTIGMEM
         def_bool y
         depends on (!SELECT_MEMORY_MODEL && ARCH_DISCONTIGMEM_ENABLE) || DISCONTIGMEM_MANUAL
 
+config SPARSEMEM
+        def_bool y
+        depends on SPARSEMEM_MANUAL
+
 config FLATMEM
         def_bool y
-        depends on !DISCONTIGMEM || FLATMEM_MANUAL
+        depends on (!DISCONTIGMEM && !SPARSEMEM) || FLATMEM_MANUAL
+
+config FLAT_NODE_MEM_MAP
+        def_bool y
+        depends on !SPARSEMEM
 
 #
 # Both the NUMA code and DISCONTIGMEM use arrays of pg_data_t's
@@ -56,4 +88,4 @@ config NEED_MULTIPLE_NODES
 
 config HAVE_MEMORY_PRESENT
         def_bool y
-        depends on ARCH_HAVE_MEMORY_PRESENT
+        depends on ARCH_HAVE_MEMORY_PRESENT || SPARSEMEM