diff --git a/src/kernel/boot/multiboot.c b/src/kernel/boot/multiboot.c
index 8dc2822..44f3076 100644
--- a/src/kernel/boot/multiboot.c
+++ b/src/kernel/boot/multiboot.c
@@ -50,7 +50,8 @@ int parse_multiboot2(struct taglist *tags)
         break;
       case MBOOT2_MMAP:
         mmap = kernel_boot_data.mmap = (void *)tag->data;
-        kernel_boot_data.mmap_size = (tag->size - 8)/mmap->entry_size;
+        kernel_boot_data.mmap_len = (tag->size - 8)/mmap->entry_size;
+        kernel_boot_data.mmap_size = (tag->size - 8);
         break;
       default:
         debug_warning("Unknown multiboot tag type:%d \n", tag->type);
@@ -76,7 +77,7 @@ int multiboot_init(uint64_t magic, void *mboot_info)
 
 int multiboot_get_memory_area(size_t count, uintptr_t *start, uintptr_t *end, uint32_t *type)
 {
-  if(count >= kernel_boot_data.mmap_size) return 1;
+  if(count >= kernel_boot_data.mmap_len) return 1;
 
   struct mmap *mmap = kernel_boot_data.mmap;
   struct mmap_entry *entry = mmap->entries;
@@ -87,3 +88,16 @@ int multiboot_get_memory_area(size_t count, uintptr_t *start, uintptr_t *end, ui
   *type = entry->type;
   return 0;
 }
+
+int multiboot_page_used(uintptr_t start)
+{
+#define overlap(st, len) ((uintptr_t)st < (start + PAGE_SIZE) && start <= ((uintptr_t)st + len))
+  if(
+      overlap(kernel_boot_data.bootloader, strlen(kernel_boot_data.bootloader)) ||
+      overlap(kernel_boot_data.commandline, strlen(kernel_boot_data.commandline)) ||
+      overlap(kernel_boot_data.mmap, kernel_boot_data.mmap_size) ||
+    0)
+    return 1;
+
+  return 0;
+}
diff --git a/src/kernel/boot/multiboot.tt b/src/kernel/boot/multiboot.tt
index 61e8366..f964016 100644
--- a/src/kernel/boot/multiboot.tt
+++ b/src/kernel/boot/multiboot.tt
@@ -161,7 +161,7 @@ TEST(reads_mmap_tag)
   );
   multiboot_init(MAGIC, tags);
 
-  ASSERT_EQ_INT(kernel_boot_data.mmap_size, 1);
+  ASSERT_EQ_INT(kernel_boot_data.mmap_len, 1);
   free(tags);
 }
 void setup_memory_areas()
@@ -179,7 +179,7 @@ void setup_memory_areas()
 TEST(reads_multiple_mmap_tags)
 {
   setup_memory_areas();
-  ASSERT_EQ_INT(kernel_boot_data.mmap_size, 2);
+  ASSERT_EQ_INT(kernel_boot_data.mmap_len, 2);
 }
 TEST(returns_memory_area_start)
 {
diff --git a/src/kernel/include/multiboot.h b/src/kernel/include/multiboot.h
index 8423415..c758987 100644
--- a/src/kernel/include/multiboot.h
+++ b/src/kernel/include/multiboot.h
@@ -7,6 +7,7 @@ struct kernel_boot_data_st
   char *bootloader;
   char *commandline;
   size_t mmap_size;
+  unsigned int mmap_len;
   void *mmap;
 };
 
@@ -16,3 +17,4 @@ extern struct kernel_boot_data_st kernel_boot_data;
 
 int multiboot_init(uint64_t magic, void *mboot_info);
 int multiboot_get_memory_area(size_t count, uintptr_t *start, uintptr_t *end, uint32_t *type);
+int multiboot_page_used(uintptr_t start);
diff --git a/src/kernel/memory/memory.c b/src/kernel/memory/memory.c
index 9f2f53f..3d8ff36 100644
--- a/src/kernel/memory/memory.c
+++ b/src/kernel/memory/memory.c
@@ -17,6 +17,8 @@ void memory_init()
     {
       if(p >= V2P(&kernel_start) && p < V2P(&kernel_end))
         continue;
+      if(multiboot_page_used(p))
+        continue;
 
       uint64_t addr = (uint64_t)P2V(p);
       uint64_t page = vmm_get_page(kernel_P4, addr);