diff -ru usr/src/nv/nv-linux.h usr/src/nv.1155389/nv-linux.h
--- usr/src/nv/nv-linux.h	2004-11-03 22:53:00.000000000 +0100
+++ usr/src/nv.1155389/nv-linux.h	2004-11-04 11:47:05.000000000 +0100
@@ -729,12 +729,21 @@
         return order;
     }
 
+/* mark memory UC-, rather than UC (don't use _PAGE_PWT) */
+static inline pgprot_t pgprot_noncached_weak(pgprot_t old_prot)
+    {
+        pgprot_t new_prot = old_prot;
+        if (boot_cpu_data.x86 > 3)
+            new_prot = __pgprot(pgprot_val(old_prot) | _PAGE_PCD);
+        return new_prot;
+    }
+
 #if !defined (pgprot_noncached)
 static inline pgprot_t pgprot_noncached(pgprot_t old_prot)
     {
         pgprot_t new_prot = old_prot;
         if (boot_cpu_data.x86 > 3)
-            new_prot = __pgprot(pgprot_val(old_prot) | _PAGE_PCD);
+            new_prot = __pgprot(pgprot_val(old_prot) | _PAGE_PCD | _PAGE_PWT);
         return new_prot;
     }
 #endif
diff -ru usr/src/nv/nv.c usr/src/nv.1155389/nv.c
--- usr/src/nv/nv.c	2004-11-03 22:53:00.000000000 +0100
+++ usr/src/nv.1155389/nv.c	2004-11-04 11:47:05.000000000 +0100
@@ -1551,7 +1551,7 @@
     /* NV fb space */
     else if (IS_FB_OFFSET(nv, NV_VMA_OFFSET(vma), vma->vm_end - vma->vm_start))
     {
-        vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+        vma->vm_page_prot = pgprot_noncached_weak(vma->vm_page_prot);
         if (NV_REMAP_PAGE_RANGE(vma->vm_start,
                              NV_VMA_OFFSET(vma),
                              vma->vm_end - vma->vm_start,