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

On 7/14/17 3:56 AM, Martin Kletzander wrote: > On Tue, Jul 11, 2017 at 03:47:55PM -0400, Liang Yan wrote: >> 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? >> > > It is not in older QEMUs which we need to stay compatible with. > Yes, Peter said similar things that kernel may not include newer driver. >> I am wondering which solution is better? >> 1. simple switch sequence and check virtio_scsi first >> > > We can't do that. We have to keep parsing older XMLs (that did not have > the model in them) the same way as we were before so that we keep stable > guest ABI. > >> 2. add extra option for "virsh attach-disk" to choose specific >> controller type >> > > Or you can first attach the controller and then attach-device with the > xml that specifies that particular controller. attach-disk is a > syntactic sugar for attach-device IIRC. > Yes, this is our current workaround. Some users are just wondering if could finish this process by command line(attach-disk) in one step. I checked the options of attach-disk that "-targetbus" is a close one but focus on high level bus controller.