Index: kernel/generic/include/macros.h
===================================================================
--- kernel/generic/include/macros.h	(revision 4d0f97d471fbaabc58b82a040cdf0bfd40b95dd1)
+++ kernel/generic/include/macros.h	(revision e2650d358e06533dcf2c3cf90e673dffacd29dd3)
@@ -47,4 +47,5 @@
  * @param s2  Start address of the second interval.
  * @param sz2 Size of the second interval.
+ *
  */
 NO_TRACE static inline int overlaps(uintptr_t s1, size_t sz1, uintptr_t s2,
@@ -55,4 +56,21 @@
 	
 	return ((s1 < e2) && (s2 < e1));
+}
+
+/** Return true if the second interval is within the first interval.
+ *
+ * @param s1  Start address of the first interval.
+ * @param sz1 Size of the first interval.
+ * @param s2  Start address of the second interval.
+ * @param sz2 Size of the second interval.
+ *
+ */
+NO_TRACE static inline int iswithin(uintptr_t s1, size_t sz1, uintptr_t s2,
+    size_t sz2)
+{
+	uintptr_t e1 = s1 + sz1;
+	uintptr_t e2 = s2 + sz2;
+	
+	return ((s1 <= s2) && (e1 >= e2));
 }
 
@@ -74,5 +92,5 @@
 
 /* Compute overlapping of physical addresses */
-#define PA_overlaps(x, szx, y, szy) \
+#define PA_OVERLAPS(x, szx, y, szy) \
 	overlaps(KA2PA((x)), (szx), KA2PA((y)), (szy))
 
Index: kernel/generic/src/main/main.c
===================================================================
--- kernel/generic/src/main/main.c	(revision 4d0f97d471fbaabc58b82a040cdf0bfd40b95dd1)
+++ kernel/generic/src/main/main.c	(revision e2650d358e06533dcf2c3cf90e673dffacd29dd3)
@@ -147,5 +147,5 @@
 	size_t i;
 	for (i = 0; i < init.cnt; i++) {
-		if (PA_overlaps(config.stack_base, config.stack_size,
+		if (PA_OVERLAPS(config.stack_base, config.stack_size,
 		    init.tasks[i].addr, init.tasks[i].size))
 			config.stack_base = ALIGN_UP(init.tasks[i].addr +
@@ -155,5 +155,5 @@
 	/* Avoid placing stack on top of boot allocations. */
 	if (ballocs.size) {
-		if (PA_overlaps(config.stack_base, config.stack_size,
+		if (PA_OVERLAPS(config.stack_base, config.stack_size,
 		    ballocs.base, ballocs.size))
 			config.stack_base = ALIGN_UP(ballocs.base +
Index: kernel/generic/src/mm/frame.c
===================================================================
--- kernel/generic/src/mm/frame.c	(revision 4d0f97d471fbaabc58b82a040cdf0bfd40b95dd1)
+++ kernel/generic/src/mm/frame.c	(revision e2650d358e06533dcf2c3cf90e673dffacd29dd3)
@@ -121,5 +121,6 @@
  *
  */
-NO_TRACE static size_t zones_insert_zone(pfn_t base, size_t count)
+NO_TRACE static size_t zones_insert_zone(pfn_t base, size_t count,
+    zone_flags_t flags)
 {
 	if (zones.count + 1 == ZONES_MAX) {
@@ -131,10 +132,23 @@
 	for (i = 0; i < zones.count; i++) {
 		/* Check for overlap */
-		if (overlaps(base, count,
-		    zones.info[i].base, zones.info[i].count)) {
-			printf("Zone (%p, %p) overlaps with zone (%p, %p)!\n",
-			    PFN2ADDR(base), PFN2ADDR(base + count),
-			    PFN2ADDR(zones.info[i].base),
-			    PFN2ADDR(zones.info[i].base + zones.info[i].count));
+		if (overlaps(zones.info[i].base, zones.info[i].count,
+		    base, count)) {
+			
+			/*
+			 * If the overlaping zones are of the same type
+			 * and the new zone is completely within the previous
+			 * one, then quietly ignore the new zone.
+			 *
+			 */
+			
+			if ((zones.info[i].flags != flags) ||
+			    (!iswithin(zones.info[i].base, zones.info[i].count,
+			    base, count))) {
+				printf("Zone (%p, %p) overlaps with previous zone (%p, %p)!\n",
+				    PFN2ADDR(base), PFN2ADDR(count),
+				    PFN2ADDR(zones.info[i].base),
+				    PFN2ADDR(zones.info[i].count));
+			}
+			
 			return (size_t) -1;
 		}
@@ -898,5 +912,5 @@
 		}
 		
-		size_t znum = zones_insert_zone(start, count);
+		size_t znum = zones_insert_zone(start, count, flags);
 		if (znum == (size_t) -1) {
 			irq_spinlock_unlock(&zones.lock, true);
@@ -921,5 +935,5 @@
 	
 	/* Non-available zone */
-	size_t znum = zones_insert_zone(start, count);
+	size_t znum = zones_insert_zone(start, count, flags);
 	if (znum == (size_t) -1) {
 		irq_spinlock_unlock(&zones.lock, true);