diff --git a/arch/sim/src/sim/sim_createstack.c b/arch/sim/src/sim/sim_createstack.c
index cbadcb0528d..fc7557b3827 100644
--- a/arch/sim/src/sim/sim_createstack.c
+++ b/arch/sim/src/sim/sim_createstack.c
@@ -35,6 +35,12 @@
 
 #include "sim_internal.h"
 
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define STACK_MARGIN_WORDS  32
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -171,7 +177,7 @@ void nostackprotect_function sim_stack_color(void *stackbase,
   if (nbytes == 0) /* 0: colorize the running stack */
     {
       stkend = up_getsp();
-      if (stkend > (uintptr_t)&sp)
+      if (stkend < (uintptr_t)&sp)
         {
           stkend = (uintptr_t)&sp;
         }
@@ -183,6 +189,7 @@ void nostackprotect_function sim_stack_color(void *stackbase,
 
   stkend = STACK_ALIGN_DOWN(stkend);
   nwords = (stkend - (uintptr_t)stackbase) >> 2;
+  nwords = nwords > STACK_MARGIN_WORDS ? nwords - STACK_MARGIN_WORDS : 0;
 
   /* Set the entire stack to the coloration value */