diff --git a/repos/base-sel4/src/core/ram_session_support.cc b/repos/base-sel4/src/core/ram_session_support.cc
index e21e53b910..923815e2b8 100644
--- a/repos/base-sel4/src/core/ram_session_support.cc
+++ b/repos/base-sel4/src/core/ram_session_support.cc
@@ -11,9 +11,6 @@
  * under the terms of the GNU General Public License version 2.
  */
 
-/* Genode includes */
-#include <base/log.h>
-
 /* core includes */
 #include <ram_session_component.h>
 #include <platform.h>
@@ -25,45 +22,54 @@ using namespace Genode;
 
 void Ram_session_component::_export_ram_ds(Dataspace_component *ds)
 {
-	size_t const num_pages = ds->size() >> get_page_size_log2();
+	size_t const page_rounded_size = (ds->size() + get_page_size() - 1) & get_page_mask();
+	size_t const num_pages = page_rounded_size >> get_page_size_log2();
+
 	Untyped_memory::convert_to_page_frames(ds->phys_addr(), num_pages);
 }
 
 
 void Ram_session_component::_revoke_ram_ds(Dataspace_component *ds)
 {
-	Untyped_memory::convert_to_untyped_frames(ds->phys_addr(), ds->size());
+	size_t const page_rounded_size = (ds->size() + get_page_size() - 1) & get_page_mask();
+
+	Untyped_memory::convert_to_untyped_frames(ds->phys_addr(), page_rounded_size);
 }
 
 
 void Ram_session_component::_clear_ds (Dataspace_component *ds)
 {
-	size_t page_rounded_size = (ds->size() + get_page_size() - 1) & get_page_mask();
+	size_t const page_rounded_size = (ds->size() + get_page_size() - 1) & get_page_mask();
 
-	/* allocate range in core's virtual address space */
-	void *virt_addr;
-	if (!platform()->region_alloc()->alloc(page_rounded_size, &virt_addr)) {
-		error("could not allocate virtual address range in core of size ",
-		      page_rounded_size);
-		return;
+	enum { ONE_PAGE = 1 };
+
+	/* allocate one page in core's virtual address space */
+	void *virt_addr_ptr = nullptr;
+	if (!platform()->region_alloc()->alloc(get_page_size(), &virt_addr_ptr) ||
+	    !virt_addr_ptr)
+		ASSERT(!"could not map 4k inside core");
+
+	addr_t const virt_addr = reinterpret_cast<addr_t const>(virt_addr_ptr);
+
+	/* map each page of dataspace one at a time and clear it */
+	for (addr_t offset = 0; offset < page_rounded_size; offset += get_page_size())
+	{
+		addr_t const phys_addr = ds->phys_addr() + offset;
+
+		/* map one physical page to the core-local address */
+		if (!map_local(phys_addr, virt_addr, ONE_PAGE)) {
+			ASSERT(!"could not map 4k inside core");
+		}
+
+		/* clear one page */
+		size_t num_longwords = get_page_size()/sizeof(long);
+		for (long *dst = reinterpret_cast<long *>(virt_addr); num_longwords--;)
+			*dst++ = 0;
+
+		/* unmap cleared page from core */
+		unmap_local(virt_addr, ONE_PAGE);
 	}
 
-	/* map the dataspace's physical pages to core-local virtual addresses */
-	size_t num_pages = page_rounded_size >> get_page_size_log2();
-	if (!map_local(ds->phys_addr(), (addr_t)virt_addr, num_pages)) {
-		error("could not map virtual address range in core of size ",
-		      page_rounded_size);
-		return;
-	}
-
-	/* clear dataspace */
-	size_t num_longwords = page_rounded_size/sizeof(long);
-	for (long *dst = (long *)virt_addr; num_longwords--;)
-		*dst++ = 0;
-
-	/* unmap dataspace from core */
-	unmap_local((addr_t)virt_addr, num_pages);
-
 	/* free core's virtual address space */
-	platform()->region_alloc()->free(virt_addr, page_rounded_size);
+	platform()->region_alloc()->free(virt_addr_ptr, get_page_size());
 }