TCK regression from blockdev change

Hi all, I noticed libvirt-tck test 207-disk-media-change.t is failing with 6.1.0, although I _think_ the failure has actually been around since the change to using blockdev in the qemu driver. The test essentially creates a minimal domain with a cdrom disk device, then calls attach_device a few times, changing the <source> of the disk. The last attach_device uses the same <source> as when the domain was created and expects the initial and final XML to be the same. For reference, here's a link to the test https://libvirt.org/git/?p=libvirt-tck.git;a=blob;f=scripts/domain/207-di... However the test fails since the 'index' attribute of the <source> element is not the same between initial XML (index='1') and final XML (index='5'). Indeed with each attach operation the index is incremented. Should libvirt be fixed to always provide an index of 1 for this disk config? Or should we adjust the test case? I'm not so familiar with this functionality but I lean towards the former since attaching a disk with a missing source (no media) results in odd looking disk config <disk type='file' device='cdrom'> <driver name='qemu' type='raw' cache='none'/> <source index='4'/> <target dev='hdc' bus='ide'/> <readonly/> <alias name='ide0-1-0'/> <address type='drive' controller='0' bus='1' target='0' unit='0'/> </disk> Regards, Jim