diff --git a/Makefile.rule b/Makefile.rule
index 0d7c45ead..4a6e4e9f1 100644
--- a/Makefile.rule
+++ b/Makefile.rule
@@ -163,10 +163,11 @@ COMMON_PROF = -pg
 # Build Debug version
 # DEBUG = 1
 
-# Improve GEMV and GER for small matrices by stack allocation.
-# For details, https://github.com/xianyi/OpenBLAS/pull/482
+# Set maximum stack allocation.
+# The default value is 2048. 0 disable stack allocation a may reduce GER and GEMV
+# performance. For details, https://github.com/xianyi/OpenBLAS/pull/482
 #
- MAX_STACK_ALLOC=2048
+# MAX_STACK_ALLOC = 0
 
 # Add a prefix or suffix to all exported symbol names in the shared library.
 # Avoid conflicts with other BLAS libraries, especially when using
diff --git a/Makefile.system b/Makefile.system
index 9de9232ad..b3e83e2dd 100644
--- a/Makefile.system
+++ b/Makefile.system
@@ -328,7 +328,8 @@ ifdef SANITY_CHECK
 CCOMMON_OPT	+= -DSANITY_CHECK -DREFNAME=$(*F)f$(BU)
 endif
 
-ifdef MAX_STACK_ALLOC
+MAX_STACK_ALLOC ?= 2048
+ifneq ($(MAX_STACK_ALLOC), 0)
 CCOMMON_OPT	+= -DMAX_STACK_ALLOC=$(MAX_STACK_ALLOC)
 endif