diff -pruN ../orig-linux-2.6.18/arch/i386/mm/pgtable.c ./arch/i386/mm/pgtable.c
--- ../orig-linux-2.6.18/arch/i386/mm/pgtable.c	2006-09-20 04:42:06.000000000 +0100
+++ ./arch/i386/mm/pgtable.c	2007-01-17 17:19:36.000000000 +0000
@@ -12,6 +12,7 @@
 #include <linux/slab.h>
 #include <linux/pagemap.h>
 #include <linux/spinlock.h>
+#include <linux/module.h>
 
 #include <asm/system.h>
 #include <asm/pgtable.h>
@@ -137,6 +138,10 @@ void set_pmd_pfn(unsigned long vaddr, un
 	__flush_tlb_one(vaddr);
 }
 
+static int nr_fixmaps = 0;
+unsigned long __FIXADDR_TOP = 0xfffff000;
+EXPORT_SYMBOL(__FIXADDR_TOP);
+
 void __set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t flags)
 {
 	unsigned long address = __fix_to_virt(idx);
@@ -146,6 +151,13 @@ void __set_fixmap (enum fixed_addresses 
 		return;
 	}
 	set_pte_pfn(address, phys >> PAGE_SHIFT, flags);
+	nr_fixmaps++;
+}
+
+void set_fixaddr_top(unsigned long top)
+{
+	BUG_ON(nr_fixmaps > 0);
+	__FIXADDR_TOP = top - PAGE_SIZE;
 }
 
 pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
diff -pruN ../orig-linux-2.6.18/include/asm-i386/fixmap.h ./include/asm-i386/fixmap.h
--- ../orig-linux-2.6.18/include/asm-i386/fixmap.h	2006-09-20 04:42:06.000000000 +0100
+++ ./include/asm-i386/fixmap.h	2007-01-17 17:19:36.000000000 +0000
@@ -19,7 +19,7 @@
  * Leave one empty page between vmalloc'ed areas and
  * the start of the fixmap.
  */
-#define __FIXADDR_TOP	0xfffff000
+extern unsigned long __FIXADDR_TOP;
 
 #ifndef __ASSEMBLY__
 #include <linux/kernel.h>
@@ -94,6 +94,8 @@ enum fixed_addresses {
 extern void __set_fixmap (enum fixed_addresses idx,
 					unsigned long phys, pgprot_t flags);
 
+extern void set_fixaddr_top(unsigned long top);
+
 #define set_fixmap(idx, phys) \
 		__set_fixmap(idx, phys, PAGE_KERNEL)
 /*
diff -pruN ../orig-linux-2.6.18/include/asm-i386/page.h ./include/asm-i386/page.h
--- ../orig-linux-2.6.18/include/asm-i386/page.h	2006-09-20 04:42:06.000000000 +0100
+++ ./include/asm-i386/page.h	2007-01-17 17:19:36.000000000 +0000
@@ -122,7 +122,7 @@ extern int page_is_ram(unsigned long pag
 
 #define PAGE_OFFSET		((unsigned long)__PAGE_OFFSET)
 #define VMALLOC_RESERVE		((unsigned long)__VMALLOC_RESERVE)
-#define MAXMEM			(-__PAGE_OFFSET-__VMALLOC_RESERVE)
+#define MAXMEM			(__FIXADDR_TOP-__PAGE_OFFSET-__VMALLOC_RESERVE)
 #define __pa(x)			((unsigned long)(x)-PAGE_OFFSET)
 #define __va(x)			((void *)((unsigned long)(x)+PAGE_OFFSET))
 #define pfn_to_kaddr(pfn)      __va((pfn) << PAGE_SHIFT)