diff --git a/base-fiasco/src/core/platform.cc b/base-fiasco/src/core/platform.cc
index 9a83f09a26..a5a3cbdb9f 100644
--- a/base-fiasco/src/core/platform.cc
+++ b/base-fiasco/src/core/platform.cc
@@ -187,6 +187,14 @@ struct Region
 
 	Region() : start(0), end(0) { }
 	Region(addr_t s, addr_t e) : start(s), end(e) { }
+
+	/**
+	 * Returns true if the specified range intersects with the region
+	 */
+	bool intersects(addr_t base, size_t size) const
+	{
+		return (((base + size) > start) && (base < end));
+	}
 };
 
 
@@ -296,8 +304,11 @@ void Platform::_setup_mem_alloc()
 				}
 
 				region.start = addr; region.end = addr + size;
-				add_region(region, _ram_alloc);
-				add_region(region, _core_address_ranges());
+				if (!region.intersects(Native_config::context_area_virtual_base(),
+				                       Native_config::context_area_virtual_size())) {
+					add_region(region, _ram_alloc);
+					add_region(region, _core_address_ranges());
+				}
 				remove_region(region, _io_mem_alloc);
 				remove_region(region, _region_alloc);
 			}
diff --git a/base-foc/src/core/platform.cc b/base-foc/src/core/platform.cc
index 93f1a648b6..8c73276b64 100644
--- a/base-foc/src/core/platform.cc
+++ b/base-foc/src/core/platform.cc
@@ -171,6 +171,14 @@ struct Region
 
 	Region() : start(0), end(0) { }
 	Region(addr_t s, addr_t e) : start(s), end(e) { }
+
+	/**
+	 * Returns true if the specified range intersects with the region
+	 */
+	bool intersects(addr_t base, size_t size) const
+	{
+		return (((base + size) > start) && (base < end));
+	}
 };
 
 
@@ -308,8 +316,11 @@ void Platform::_setup_mem_alloc()
 				}
 
 				region.start = addr; region.end = addr + size;
-				add_region(region, _ram_alloc);
-				add_region(region, _core_address_ranges());
+				if (!region.intersects(Native_config::context_area_virtual_base(),
+				                       Native_config::context_area_virtual_size())) {
+					add_region(region, _ram_alloc);
+					add_region(region, _core_address_ranges());
+				}
 				remove_region(region, _io_mem_alloc);
 				remove_region(region, _region_alloc);
 			}
diff --git a/base-pistachio/src/core/include/map_local.h b/base-pistachio/src/core/include/map_local.h
index 9539329798..e0a1be03cb 100644
--- a/base-pistachio/src/core/include/map_local.h
+++ b/base-pistachio/src/core/include/map_local.h
@@ -20,6 +20,7 @@
 
 /* Pistachio includes */
 namespace Pistachio {
+#include <l4/space.h>
 #include <l4/types.h>
 #include <l4/ipc.h>
 #include <l4/kdebug.h>
@@ -40,7 +41,7 @@ namespace Genode {
 	 */
 	inline static bool map_local(addr_t from_addr, addr_t to_addr, size_t num_pages)
 	{
-	
+
 		Native_thread_id core_pager = platform_specific()->core_pager()->native_thread_id();
 
 		addr_t offset = 0;
@@ -85,7 +86,14 @@ namespace Genode {
 	 */
 	inline void unmap_local(addr_t virt, size_t num_pages)
 	{
-		PERR("unmap_local() called - not implemented yet");
+		size_t page_size = get_page_size();
+		addr_t offset = 0;
+		for (unsigned i = 0; i < num_pages; i++, offset += page_size) {
+			using namespace Pistachio;
+			L4_Fpage_t fpage = L4_Fpage(virt + offset, page_size);
+			fpage += L4_FullyAccessible;
+			L4_Flush(fpage);
+		}
 	}
 }
 
diff --git a/base-pistachio/src/core/platform.cc b/base-pistachio/src/core/platform.cc
index 4a7fa3ba13..96a05a76f7 100644
--- a/base-pistachio/src/core/platform.cc
+++ b/base-pistachio/src/core/platform.cc
@@ -21,6 +21,7 @@
 
 /* core includes */
 #include <core_parent.h>
+#include <map_local.h>
 #include <platform.h>
 #include <platform_thread.h>
 #include <platform_pd.h>
@@ -247,6 +248,14 @@ struct Region
 
 	Region() : start(0), end(0) { }
 	Region(addr_t s, addr_t e) : start(s), end(e) { }
+
+	/**
+	 * Returns true if the specified range intersects with the region
+	 */
+	bool intersects(addr_t base, size_t size) const
+	{
+		return (((base + size) > start) && (base < end));
+	}
 };
 
 
@@ -396,8 +405,13 @@ void Platform::_setup_mem_alloc()
 
 				} else {
 					region.start = addr; region.end = addr + size;
-					add_region(region, _ram_alloc);
-					add_region(region, _core_address_ranges());
+					if (!region.intersects(Native_config::context_area_virtual_base(),
+					                       Native_config::context_area_virtual_size())) {
+						add_region(region, _ram_alloc);
+						add_region(region, _core_address_ranges());
+					} else {
+						unmap_local(region.start, size >> get_page_size_log2());
+					}
 					remove_region(region, _io_mem_alloc);
 					remove_region(region, _region_alloc);
 				}