You should certainly install all the redhat virtual

drivers for disks and network if you haven't already:

https://www.linux-kvm.org/page/WindowsGuestDrivers

[X] NetKVM/ - Virtio network driver

[X] viostor/ - Virtio block driver

[ ] vioscsi/ - Virtio Small Computer System Interface (SCSI) driver

[ ] viorng/ - Virtio RNG driver

[X] vioser/ - Virtio serial driver

[X] Balloon/ - Virtio memory balloon driver

[ ] qxl/ - QXL graphics driver for Windows 7 and earlier. (build virtio-win-0.1.103-1 and later)

[ ] qxldod/ - QXL graphics driver for Windows 8 and later. (build virtio-win-0.1.103-2 and later)

[ ] pvpanic/ - QEMU pvpanic device driver (build virtio-win-0.1.103-2 and later)

[ ] guest-agent/ - QEMU Guest Agent 32bit and 64bit MSI installers

[ ] qemupciserial/ - QEMU PCI serial device driver

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