The Red Hat VirtIO SCSI Controller Windows driver is a driver that allows Windows guests to interact with a VirtIO SCSI controller in virtualized environments, particularly when running on a KVM/QEMU hypervisor. VirtIO is a set of standardized drivers used in virtualization to improve performance by providing high-efficiency I/O for virtual machines (VMs). The SCSI (Small Computer System Interface) controller is used for handling storage devices like hard disks in the VM.

If you're running a Windows VM on a KVM/QEMU-based hypervisor (like Red Hat Virtualization, Proxmox, oVirt, or others), you'll need to install the VirtIO SCSI driver to allow Windows to recognize and use the virtual storage devices properly.