[libvirt] qemu: hotplug virtio_scsi over lsilogic when sicsi controller is not present?

Hi, We hit some problems when we attached some lun devices in our vm, turns out that libvirt created lsilogic scsi controller automatically for these scsi devices, however these device works well under virtio_scsi controller. the current code logic is check lsilogic first, if qemu could not support it, then check virtio_scsi, however is it better to check virtio_scsi earlier? since it is supported better in qemu level? I am wondering which solution is better? 1. simple switch sequence and check virtio_scsi first 2. add extra option for "virsh attach-disk" to choose specific controller type Thanks, Liang ==================================== Code part is like below qemu_hotplug.c qemuDomainFindOrCreateSCSIDiskController /* No SCSI controller present, for backward compatibility we * now hotplug a controller */ if (VIR_ALLOC(cont) < 0) return NULL; cont->type = VIR_DOMAIN_CONTROLLER_TYPE_SCSI; cont->idx = controller; cont->model = -1; VIR_INFO("No SCSI controller present, hotplugging one"); if (qemuDomainAttachControllerDevice(driver, qemu_domain_address.c qemuDomainSetSCSIControllerModel if (qemuDomainIsPSeries(def)) { *model = VIR_DOMAIN_CONTROLLER_MODEL_SCSI_IBMVSCSI; } else if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_SCSI_LSI)) { *model = VIR_DOMAIN_CONTROLLER_MODEL_SCSI_LSILOGIC; } else if (virQEMUCapsGet(qemuCaps, QEMU_CAPS_VIRTIO_SCSI)) { *model = VIR_DOMAIN_CONTROLLER_MODEL_SCSI_VIRTIO_SCSI; } else { virReportError(VIR_ERR_INTERNAL_ERROR, "%s", _("Unable to determine model for scsi controller")); return -1;