diff --git a/conts/posix/mm0/lib/vaddr.c b/conts/posix/mm0/lib/vaddr.c
index 8a847a7..3d5d806 100644
--- a/conts/posix/mm0/lib/vaddr.c
+++ b/conts/posix/mm0/lib/vaddr.c
@@ -9,6 +9,7 @@
 #include INC_GLUE(memory.h)
 #include <lib/vaddr.h>
 #include <stdio.h>
+#include <memory.h>
 
 void vaddr_pool_init(struct id_pool *pool, unsigned long start, unsigned long end)
 {
@@ -22,12 +23,13 @@ void *vaddr_new(struct id_pool *pool, int npages)
 	if ((int)(shm_vpfn = ids_new_contiguous(pool, npages)) < 0)
 		return 0;
 
-	return (void *)__pfn_to_addr(shm_vpfn + SHM_AREA_START);
+	return (void *)__pfn_to_addr(shm_vpfn + cont_mem_regions.shmem->start);
 }
 
 int vaddr_del(struct id_pool *pool, void *vaddr, int npages)
 {
-	unsigned long idpfn = __pfn(page_align(vaddr) - SHM_AREA_START);
+	unsigned long idpfn = __pfn(page_align(vaddr) -
+				    __pfn_to_addr(cont_mem_regions.shmem->start));
 
 	if (ids_del_contiguous(pool, idpfn, npages) < 0) {
 		printf("%s: Invalid address range returned to "
diff --git a/conts/posix/mm0/mm/init.c b/conts/posix/mm0/mm/init.c
index 21b747a..df1a0bb 100644
--- a/conts/posix/mm0/mm/init.c
+++ b/conts/posix/mm0/mm/init.c
@@ -142,7 +142,7 @@ int pager_setup_task(void)
 	 * microkernel for this pager. Ensure that we also get
 	 * the same from our internal utcb bookkeeping.
 	 */
-	BUG_ON(task->utcb_address != UTCB_AREA_START);
+	BUG_ON(task->utcb_address != __pfn_to_addr(cont_mem_regions.utcb->start));
 
 	/* Pager must prefault its utcb */
 	prefault_page(task, task->utcb_address,
diff --git a/conts/posix/mm0/mm/mmap.c b/conts/posix/mm0/mm/mmap.c
index 90b6972..5f2e374 100644
--- a/conts/posix/mm0/mm/mmap.c
+++ b/conts/posix/mm0/mm/mmap.c
@@ -169,8 +169,8 @@ int mmap_address_validate(struct tcb *task, unsigned long map_address,
 	if (vm_flags & VMA_PRIVATE) {
 		if ((map_address >= task->start &&
 	    	     map_address < task->end) ||
-		    (map_address >= UTCB_AREA_START &&
-		     map_address < UTCB_AREA_END)) {
+		    (map_address >= __pfn_to_addr(cont_mem_regions.utcb->start) &&
+		     map_address < __pfn_to_addr(cont_mem_regions.utcb->end))) {
 			return 1;
 		} else
 			return 0;
@@ -181,8 +181,8 @@ int mmap_address_validate(struct tcb *task, unsigned long map_address,
 	} else if (vm_flags & VMA_SHARED) {
 		if ((map_address >= task->start &&
 	    	     map_address < task->end) ||
-		    (map_address >= SHM_AREA_START &&
-	    	     map_address < SHM_AREA_END))
+		    (map_address >= __pfn_to_addr(cont_mem_regions.shmem->start) &&
+	    	     map_address < __pfn_to_addr(cont_mem_regions.shmem->end)))
 			return 1;
 		else
 			return 0;
diff --git a/conts/posix/mm0/mm/shm.c b/conts/posix/mm0/mm/shm.c
index 7338bf1..370a926 100644
--- a/conts/posix/mm0/mm/shm.c
+++ b/conts/posix/mm0/mm/shm.c
@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <task.h>
 #include <mmap.h>
+#include <memory.h>
 #include <vm_area.h>
 #include <globals.h>
 #include <lib/malloc.h>
@@ -62,8 +63,11 @@ int shm_pool_init()
 	}
 
 	/* Initialise the global shm virtual address pool */
-	if ((err = address_pool_init(&shm_vaddr_pool,
-				     SHM_AREA_START, SHM_AREA_END)) < 0) {
+	if ((err =
+	     address_pool_init(&shm_vaddr_pool,
+			       __pfn_to_addr(cont_mem_regions.shmem->start),
+			       __pfn_to_addr(cont_mem_regions.shmem->end)))
+	     < 0) {
 		printf("SHM Address pool initialisation failed.\n");
 		return err;
 	}
diff --git a/conts/posix/mm0/mm/task.c b/conts/posix/mm0/mm/task.c
index d4e199e..41c07c0 100644
--- a/conts/posix/mm0/mm/task.c
+++ b/conts/posix/mm0/mm/task.c
@@ -519,8 +519,8 @@ int task_map_stack(struct vm_file *f, struct exec_file_desc *efd,
 	char *args_on_stack;
 	void *mapped;
 
-	task->stack_end = USER_AREA_END;
-	task->stack_start = USER_AREA_END - DEFAULT_STACK_SIZE;
+	task->stack_end = __pfn_to_addr(cont_mem_regions.task->end);
+	task->stack_start = __pfn_to_addr(cont_mem_regions.task->end) - DEFAULT_STACK_SIZE;
 	task->args_end = task->stack_end;
 	task->args_start = task->stack_end - stack_used;
 
@@ -636,8 +636,8 @@ int task_mmap_segments(struct tcb *task, struct vm_file *file, struct exec_file_
 	int text_size, data_size;
 
 	/* Set up task's user boundary regions */
-	task->start = USER_AREA_START;
-	task->end = USER_AREA_END;
+	task->start = __pfn_to_addr(cont_mem_regions.task->start);
+	task->end = __pfn_to_addr(cont_mem_regions.task->end);
 	task->map_start = task->start;
 	task->map_end = task->end;
 
diff --git a/conts/posix/mm0/mm/utcb.c b/conts/posix/mm0/mm/utcb.c
index 3e7c814..31f6ce0 100644
--- a/conts/posix/mm0/mm/utcb.c
+++ b/conts/posix/mm0/mm/utcb.c
@@ -10,6 +10,7 @@
 #include <utcb.h>
 #include <lib/malloc.h>
 #include <vm_area.h>
+#include <memory.h>
 
 /*
  * UTCB management in Codezero
@@ -23,8 +24,11 @@ int utcb_pool_init()
 	int err;
 
 	/* Initialise the global shm virtual address pool */
-	if ((err = address_pool_init(&utcb_region_pool,
-				     UTCB_AREA_START, UTCB_AREA_END)) < 0) {
+	if ((err =
+	     address_pool_init(&utcb_region_pool,
+			       __pfn_to_addr(cont_mem_regions.utcb->start),
+			       __pfn_to_addr(cont_mem_regions.utcb->end)))
+	    < 0) {
 		printf("UTCB address pool initialisation failed.\n");
 		return err;
 	}