diff -r 59be60d5664b xen/arch/ia64/xen/mm.c
--- a/xen/arch/ia64/xen/mm.c	Tue Jun 20 10:40:14 2006 -0600
+++ b/xen/arch/ia64/xen/mm.c	Tue Jun 20 11:43:01 2006 -0600
@@ -471,6 +471,14 @@ u64 translate_domain_pte(u64 pteval, u64
 	pteval2 |= (pteval & _PAGE_ED);
 	pteval2 |= _PAGE_PL_2; // force PL0->2 (PL3 is unaffected)
 	pteval2 = (pteval & ~_PAGE_PPN_MASK) | pteval2;
+	/*
+	 * Don't let non-dom0 domains map uncached addresses.  This can
+	 * happen when domU tries to touch i/o port space.  Also prevents
+	 * possible address aliasing issues.
+	 */
+	if (d != dom0 && pteval2 & _PAGE_MA_MASK)
+		pteval2 &= ~_PAGE_MA_MASK;
+
 	return pteval2;
 }