diff --git a/tests/qemu-iotests/005 b/tests/qemu-iotests/005
index 9abcb84e4b..ba1236dfbf 100755
--- a/tests/qemu-iotests/005
+++ b/tests/qemu-iotests/005
@@ -44,6 +44,8 @@ trap "_cleanup; exit \$status" 0 1 2 3 15
 _supported_fmt generic
 _supported_proto generic
 _supported_os Linux
+_unsupported_imgopts "subformat=twoGbMaxExtentFlat" \
+                     "subformat=twoGbMaxExtentSparse"
 
 # vpc is limited to 127GB, so we can't test it here
 if [ "$IMGFMT" = "vpc" ]; then