Comment 22 for bug 2049689

It would be good to have a second bug report about the new finding. In some way this is now working as designed but not as expected. Basically loop block devices set a generic flag to disable partition support (/sys/block/loop?/capabilities -> 0x200 GENHD_FL_NO_PART). There is a change in 5.19 which stops disabling partition support and just prevents automatic partition scanning but that needs adjustments.
In the meantime there should be a work-around by using kpartx (kpartx -a /dev/loop? -> /dev/mapper/loop?p...)