Re: [libvirt] [PATCH v5 02/16] qemu: Introduce qemuDomainDeviceDefValidateControllerAttributes

On 01/29/2018 04:18 AM, Ján Tomko wrote: > On Fri, Jan 05, 2018 at 06:47:25PM -0500, John Ferlan wrote: >> Move the checks that various attributes are not set on any controller >> other than SCSI controller using virtio-scsi model into the common >> controller validate checks. >> >> Need to also add a qemuDomainResetSCSIControllerModel call in order >> to ensure we get the "right" SCSI model if it's not set by default >> since it wouldn't be set during post parse processing. >> > > So we should set it in post-parse processing once instead of adding this > second call. > > Jan This is a point you raised in v3: https://www.redhat.com/archives/libvir-list/2017-December/msg00293.html to which I responded: https://www.redhat.com/archives/libvir-list/2017-December/msg00304.html and even carried into my v4: https://www.redhat.com/archives/libvir-list/2018-January/msg00103.html So, now that we're here again - the question becomes, do we really want post parse processing to set a default model if it's not set?

Should that be part of this series? Should it be a followup? Should be something done before this one and then rework this one?

Are there drawbacks to doing so? One drawback that I kept coming back to is that LSI becomes the default qemu model instead of VIRTIO-SCSI (it's the order of setting *model in qemuDomainSetSCSIControllerModel).

That drawback caused problems when setting the model if we create a new SCSI controller during something like hotplug because we had already filled the current controller or when adding one VIRTIO-SCSI controller but more than 7 disks (or hostdevs) that end up using that controller. Although I think that's at least partially resolved by other changes I've already made. Tks - John