RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Reproduced with -49:

$  x86_64-softmmu/qemu-system-x86_64 /mnt/vm/virt_test/images/rhel65-64.qcow2 -qmp stdio -m 1024 -S
{'execute':'qmp_capabilities'}
{"execute":"device_add","arguments":{"driver":"virtio-scsi-pci","bus":"pci.0","id":"scsi1"}}
{"execute":"device_add","arguments":{"driver":"scsi-hd","drive":"test30","id":"test30","bus": "scsi1.0"}}
{"execute":"__com.redhat_drive_add", "arguments": {"file":"/mnt/vm/virt_test/images/rhel510-64.qcow2","format":"qcow2","id":"test30", "cache": "none","aio": "native"}}
{"execute":"device_add","arguments":{"driver":"scsi-hd","drive":"test30","id":"test30","bus": "scsi1.0"}}
{"execute":"cont"}

Fixed by Amos Kong's patch "qdev: add the device to the QOM tree before using it to set a link" (http://article.gmane.org/gmane.comp.emulators.qemu/249089/raw but not yet applied) so it is probably a duplicate of some other bug.  Amos, please close it since you know best what the bug is.

*** This bug has been marked as a duplicate of bug 1046248 ***