Incidentally, I was able to fix my immediate problem by switching the disk type to scsi, based on the suggestions given by Christian Ehrhardt.
It's still an open bug that could cause other people some grief. It sure caused me plenty. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1974100 Title: inode lazy init in a VM fills virtual disk with garbage To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/qemu/+bug/1974100/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs