[PULL 3/3] iotests/197: Fix for compat=0.10

[Max Reitz <mreitz@redhat.com>]

Writing zeroes to a qcow2 v2 images without a backing file results in an
unallocated cluster as of 61b3043965.  197 has a test for COR-ing a
cluster on an image without a backing file, which means that the data
will be zero, so now on a v2 image that cluster will just stay
unallocated, and so the test fails.  Just force compat=1.1 for that
particular case to enforce the cluster to get allocated.

Fixes: 61b3043965fe3552ee2684a97e7cc809ca7a71b3
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200727135237.1096841-1-mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 tests/qemu-iotests/197 | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tests/qemu-iotests/197 b/tests/qemu-iotests/197
index 95f05b0e34..121959a09c 100755
--- a/tests/qemu-iotests/197
+++ b/tests/qemu-iotests/197
@@ -112,7 +112,9 @@ echo
 echo '=== Partial final cluster ==='
 echo
 
-_make_test_img 1024
+# Force compat=1.1, because writing zeroes on a v2 image without a
+# backing file would just result in an unallocated cluster
+_make_test_img -o compat=1.1 1024
 $QEMU_IO -f $IMGFMT -C -c 'read 0 1024' "$TEST_IMG" | _filter_qemu_io
 $QEMU_IO -f $IMGFMT -c map "$TEST_IMG"
 _check_test_img
-- 
2.26.2