diff --git a/include/metalsvm/malloc.h b/include/metalsvm/malloc.h
index feca4998..40f122c8 100644
--- a/include/metalsvm/malloc.h
+++ b/include/metalsvm/malloc.h
@@ -31,7 +31,7 @@ extern "C" {
 /// Binary exponent of minimal buddy size
 #define BUDDY_MIN	3  // 8 Byte >= sizeof(buddy_t)
 /// Binary exponent of the size which we allocate with buddy_fill()
-#define BUDDY_ALLOC	15 // 32 KByte >= PAGE_SIZE
+#define BUDDY_ALLOC	16 // 64 KByte = 16 * PAGE_SIZE
 
 #define BUDDY_LISTS	(BUDDY_MAX-BUDDY_MIN+1)
 #define BUDDY_MAGIC	0xBABE
diff --git a/include/metalsvm/vma.h b/include/metalsvm/vma.h
index 2624d993..ccb851d5 100644
--- a/include/metalsvm/vma.h
+++ b/include/metalsvm/vma.h
@@ -49,9 +49,17 @@ extern "C" {
 #define VMA_HEAP	(VMA_READ|VMA_WRITE|VMA_CACHEABLE)
 
 // boundaries for VAS allocation
-#define VMA_KERN_MIN	PAGE_SIZE	// we skip the first page
 #define VMA_KERN_MAX	KERNEL_SPACE
-#define VMA_USER_MAX	PAGE_MAP_PGT
+
+// we skip the first kb which are reserved for APICs, VGA, Multiboot, SMP etc.
+#define VMA_KERN_MIN	0xC0000
+
+// last three top level entries are reserved
+#ifdef CONFIG_X86_32
+ #define VMA_USER_MAX	0xFF400000
+#elif defined (CONFIG_X86_64)
+ #define VMA_USER_MAX	0xFFFFFE8000000000
+#endif
 
 struct vma;
 
diff --git a/mm/memory.c b/mm/memory.c
index cbbc5e75..db697612 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -35,6 +35,7 @@
 #include <asm/SCC_API.h>
 #include <asm/icc.h>
 #endif
+#include <asm/apic.h>
 
 /* 
  * Set whole address space as occupied:
@@ -54,6 +55,8 @@ atomic_int32_t total_available_pages = ATOMIC_INIT(0);
 extern const void kernel_start;
 extern const void kernel_end;
 
+extern apic_mp_t* apic_mp;
+
 inline static int page_marked(size_t i)
 {
 	size_t index = i >> 3;
@@ -306,22 +309,26 @@ int mmu_init(void)
 		PAGE_FLOOR((size_t) &kernel_end),
 		VMA_READ|VMA_WRITE|VMA_EXECUTE|VMA_CACHEABLE);
 
+	// TODO: should we move the following architecture specific VMA regions
+	//       to arch_paging_init() ?
+
+	// add Multiprocessing Tables to VMA list
+	vma_add(PAGE_CEIL((size_t) apic_mp),
+		PAGE_FLOOR((size_t) apic_mp + sizeof(apic_mp_t)),
+		VMA_READ|VMA_WRITE|VMA_EXECUTE|VMA_CACHEABLE);
+
 	// add IOAPIC and LAPIC to VMA list
-	vma_add((size_t) &kernel_start - 2*PAGE_SIZE,
-		(size_t) &kernel_start,
-		VMA_READ|VMA_WRITE);
+	vma_add(LAPIC_ADDR, LAPIC_ADDR + PAGE_SIZE, VMA_READ|VMA_WRITE);
+	vma_add(IOAPIC_ADDR, IOAPIC_ADDR + PAGE_SIZE, VMA_READ|VMA_WRITE);
 
 #ifdef CONFIG_VGA
 	// add VGA to VMA list
-	vma_add(PAGE_CEIL(VIDEO_MEM_ADDR),
-		PAGE_FLOOR(VIDEO_MEM_ADDR) + PAGE_SIZE,
-		VMA_READ|VMA_WRITE);
+	vma_add(VIDEO_MEM_ADDR, VIDEO_MEM_ADDR + PAGE_SIZE, VMA_READ|VMA_WRITE);
 #endif
 
 #if MAX_CORES > 1
 	// reserve page for SMP boot code
-	vma_add(PAGE_CEIL(SMP_SETUP_ADDR),
-		PAGE_FLOOR(SMP_SETUP_ADDR) + PAGE_SIZE,
+	vma_add(SMP_SETUP_ADDR, SMP_SETUP_ADDR + PAGE_SIZE,
 		VMA_READ|VMA_WRITE|VMA_EXECUTE|VMA_CACHEABLE);
 #endif
 
@@ -335,6 +342,12 @@ int mmu_init(void)
 			PAGE_FLOOR((size_t) mb_info + sizeof(multiboot_info_t)),
 			VMA_READ|VMA_CACHEABLE);
 
+		if (mb_info->flags & MULTIBOOT_INFO_MEM_MAP) {
+			vma_add(PAGE_CEIL((size_t) mb_info->mmap_addr),
+				PAGE_FLOOR((size_t) mb_info->mmap_addr + mb_info->mmap_length),
+				VMA_READ|VMA_CACHEABLE);
+		}
+
 		if (mb_info->flags & MULTIBOOT_INFO_MODS) {
 			multiboot_module_t* mmodule = (multiboot_module_t*) ((size_t) mb_info->mods_addr);