As a follow-up to CNV-39705, which added virtio-blk IOThread Virtqueue Mapping support, the same should be enabled for virtio-scsi disks. IOThread Virtqueue Mapping improves performance for guests that perform heavy I/O from multiple vCPUs.

The same approach as CNV-39705 can be applied to virtio-scsi. The advantage of extending support to virtio-scsi is that CNV VMs default to virtio-scsi, so users can more easily take advantage of IOThread Virtqueue Mapping without switching to virtio-blk.

Upstream support for virtio-scsi IOThread Virtqueue Mapping was added in QEMU v10.0.0-rc0 and libvirt v11.2.0 (2025-04-01). Please check the downstream backport status when beginning work on this epic.