diff --git a/i386/i386at/biosmem.c b/i386/i386at/biosmem.c
index a7a440e..2ca1f61 100644
--- a/i386/i386at/biosmem.c
+++ b/i386/i386at/biosmem.c
@@ -440,9 +440,34 @@ biosmem_find_boot_data(const struct multiboot_raw_info *mbi, uint32_t min,
     struct elf_shdr *shdr;
     uint32_t i, start, end = end;
     unsigned long tmp;
+    const struct biosmem_map_entry *entry;
 
     start = max;
 
+    /* Exclude unmapped areas */
+    i = 0;
+    entry = biosmem_map;
+    while (entry < biosmem_map + biosmem_map_size)
+    {
+        /* Exclude memory before this entry */
+        if (i < entry->base_addr)
+            biosmem_find_boot_data_update(min, &start, &end, i, entry->base_addr);
+        if (entry->type == BIOSMEM_TYPE_AVAILABLE)
+            /* Do not exclude this area */
+            i = entry->base_addr + entry->length;
+        else
+            /* Exclude this area too */
+            i = entry->base_addr;
+        entry++;
+    }
+    /* Exclude last entry and anything else beyond */
+    if (i < max)
+        biosmem_find_boot_data_update(min, &start, &end, i, max);
+
+    if (biosmem_heap_cur)
+        /* Heap is in use */
+        biosmem_find_boot_data_update(min, &start, &end, biosmem_heap_cur, biosmem_heap_end);
+
     biosmem_find_boot_data_update(min, &start, &end, _kvtophys(&_start),
                                   _kvtophys(&_end));
 
@@ -738,6 +763,8 @@ biosmem_load_segment(struct biosmem_segment *seg, uint64_t max_phys_end,
                      phys_addr_t avail_start, phys_addr_t avail_end)
 {
     unsigned int seg_index;
+    phys_addr_t start, end, max_start, max_end;
+    uint32_t next;
 
     seg_index = seg - biosmem_segments;
 
@@ -753,6 +780,34 @@ biosmem_load_segment(struct biosmem_segment *seg, uint64_t max_phys_end,
         phys_end = max_phys_end;
     }
 
+#ifndef MACH_HYP
+    max_start = phys_start;
+    max_end = phys_start;
+    next = phys_start;
+
+    do {
+	    extern struct multiboot_info boot_info;
+
+        start = next;
+        end = biosmem_find_boot_data((struct multiboot_raw_info *)&boot_info, start, phys_end, &next);
+
+        if (end == 0) {
+            end = phys_end;
+            next = 0;
+        }
+
+        if ((end - start) > (max_end - max_start)) {
+            max_start = start;
+            max_end = end;
+        }
+    } while (next != 0);
+
+    max_start = round_page(max_start);
+    max_end = trunc_page(max_end);
+
+    seg->avail_start = max_start;
+    seg->avail_end = max_end;
+#else
     if ((avail_start < phys_start) || (avail_start >= phys_end))
         avail_start = phys_start;
 
@@ -761,7 +816,9 @@ biosmem_load_segment(struct biosmem_segment *seg, uint64_t max_phys_end,
 
     seg->avail_start = avail_start;
     seg->avail_end = avail_end;
-    vm_page_load(seg_index, phys_start, phys_end, avail_start, avail_end);
+#endif
+
+    vm_page_load(seg_index, phys_start, phys_end, seg->avail_start, seg->avail_end);
 }
 
 void __init