--- a/layout/reftests/backgrounds/vector/empty/reftest.list
+++ b/layout/reftests/backgrounds/vector/empty/reftest.list
@@ -1,16 +1,18 @@
 == tall--contain--height.html ref-tall-empty.html
 == tall--contain--width.html ref-tall-empty.html
 == wide--contain--height.html ref-wide-empty.html
 == wide--contain--width.html ref-wide-empty.html
-== tall--cover--height.html ref-tall-lime.html
-== tall--cover--width.html ref-tall-lime.html
-== wide--cover--height.html ref-wide-lime.html
-== wide--cover--width.html ref-wide-lime.html
+
+# These tests fail because of integer overflow; see bug 894555.
+fails == tall--cover--height.html ref-tall-lime.html
+fails == tall--cover--width.html ref-tall-lime.html
+fails == wide--cover--height.html ref-wide-lime.html
+fails == wide--cover--width.html ref-wide-lime.html
 
 == zero-height-ratio-contain.html ref-tall-empty.html
 == zero-height-ratio-cover.html ref-tall-empty.html
 == zero-height-ratio-auto-auto.html ref-tall-empty.html
 == zero-height-ratio-auto-5px.html ref-tall-empty.html
 == zero-height-ratio-5px-auto.html ref-tall-empty.html
 == zero-width-ratio-contain.html ref-tall-empty.html
 == zero-width-ratio-cover.html ref-tall-empty.html