92ab69b61f
qemu-iotests supports the -nocache option which makes the tests run with cache=none. For blkdebug tests with qcow2 this means that we may see test results that differ from cache=writethrough. This patch makes the diff a bit smaller and therefore easier to review. Signed-off-by: Kevin Wolf <kwolf@redhat.com> Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>