CNV-71192: Add TP support for custom video device selection when creating a VM

Author: MirzWeiss

modules/virt-creating-vm-cli.adoc

@@ -6,6 +6,7 @@
 [id="virt-creating-vm-cli_{context}"]
 = Creating a VM from a VirtualMachine manifest
 
+[role="_abstract"]
 You can create a virtual machine (VM) from a `VirtualMachine` manifest. To simplify the creation of these manifests, you can use the `virtctl` command-line tool.
 
 .Prerequisites
@@ -35,29 +36,31 @@ This example manifest does not configure VM authentication.
 apiVersion: kubevirt.io/v1
 kind: VirtualMachine
 metadata:
-  name: rhel-9-minimal # <1>
+  name: rhel-9-minimal
 spec:
   dataVolumeTemplates:
   - metadata:
       name: imported-volume-mk4lj
     spec:
       sourceRef:
         kind: DataSource
-        name: rhel9 # <2>
-        namespace: openshift-virtualization-os-images # <3>
+        name: rhel9
+        namespace: openshift-virtualization-os-images
       storage:
         resources: {}
   instancetype:
-    inferFromVolume: imported-volume-mk4lj # <4>
+    inferFromVolume: imported-volume-mk4lj
     inferFromVolumeFailurePolicy: Ignore
   preference:
-    inferFromVolume: imported-volume-mk4lj # <5>
+    inferFromVolume: imported-volume-mk4lj
     inferFromVolumeFailurePolicy: Ignore
   runStrategy: Always
   template:
     spec:
       domain:
-        devices: {}
+        devices:
+          video:
+            type: virtio
         memory:
           guest: 512Mi
         resources: {}
@@ -67,11 +70,14 @@ spec:
           name: imported-volume-mk4lj
         name: imported-volume-mk4lj
 ----
-<1> The VM name.
-<2> The boot source for the guest operating system.
-<3> The namespace for the boot source. Golden images are stored in the `openshift-virtualization-os-images` namespace.
-<4> The instance type is inferred from the selected `DataSource` object.
-<5> The preference is inferred from the selected `DataSource` object.
++
+
+* `name: rhel-9-minimal` specifies the name of the VM.
+* `name: rhel9` specifies the boot source for the guest operating system in the `sourceRef` section.
+* `namespace: openshift-virtualization-os-images` specifies the namespace for the boot source. Golden images are stored in the `openshift-virtualization-os-images` namespace.
+* `instancetype: inferFromVolume: imported-volume-mk4lj` specifies the instance type inferred from the selected `DataSource` object.
+* `preference: inferFromVolume: imported-volume-mk4lj` specifies that the preference is inferred from the selected `DataSource` object.
+* `type: virtio` specifies the use of a custom video device (a VirtIO device in this example) to enable hardware graphics acceleration. Enabling a custom video device is in Technology Preview for {VirtProductName} 4.21.
 
 . Create a virtual machine by using the manifest file:
 +

modules/virt-supported-custom-video-devices.adoc

@@ -0,0 +1,43 @@
+// Module included in the following assemblies:
+//
+// * virt/creating_vms_advanced/creating_vms_cli/virt-creating-vms-from-cli.adoc
+
+:_mod-docs-content-type: REFERENCE
+[id="virt-supported-custom-video-devices_{context}"]
+= Supported custom video device types
+
+[role="_abstract"]
+When creating a virtual machine (VM), you can configure a custom video device type to override the default video configuration.
+
+Configuring a custom video device allows you to specify different video devices, based on your guest operating system requirements and performance needs.
+
+[IMPORTANT]
+====
+Custom video device support is a Technology Preview feature only. Technology Preview features are not supported with Red{nbsp}Hat production service level agreements (SLAs) and might not be functionally complete. Red{nbsp}Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.
+
+For more information about the support scope of Red{nbsp}Hat Technology Preview features, see link:https://access.redhat.com/support/offerings/techpreview/[Technology Preview Features Support Scope].
+====
+
+Using a custom video device  provides several advantages:
+
+Performance:: Certain video devices provide better performance than the default configuration. For example, VirtIO is a more efficient video device on AMD/x86_64 architecture than legacy VGA.
+Resolution flexibility:: With some viodeo device types, you can set custom display resolutions.
+Memory efficiency:: Some video types are more memory efficient for headless or console-only operations.
+
+You can configure the following video device types:
+
+* VirtIO: provides improved performance, and hardware-accelerated video decoding and encoding by offloading tasks to the host. Recommended for modern guest operating systems with available `VirtIO` drivers.
+* VGA: the standard for analog video display (default on AMD/x86_64 with BIOS).
+* Bochs: an emulated graphics adapter that provides a simple interface for guest operating systems to manage display settings (default on AMD/x86_64 with EFI).
+* Cirrus: a legacy video device that provides stable video output.
+* ramfb:  a simple, unaccelerated virtual display device primarily used in the QEMU emulator, and useful for ARM architecture.
+
+[cols="1,1,1,1",options="header"]
+.Video device support by architecture
+|====
+|Architecture |Boot mode |Default type |Supported types
+| AMD/x86_64  | BIOS     | `vga`       | `virtio`, `vga`, `bochs`, `cirrus`, `ramfb``
+| AMD/x86_64  | EFI      | `bochs`     | `virtio`, `vga`, `bochs`, `cirrus`, `ramfb``
+| ARM64       | BIOS/EFI | `virtio`    | `virtio`, `ramfb`
+| s390x       | BIOS/EFI | `virtio`    | `virtio`
+|====

virt/creating_vms_advanced/creating_vms_cli/virt-creating-vms-from-cli.adoc

@@ -6,6 +6,7 @@ include::_attributes/common-attributes.adoc[]
 
 toc::[]
 
+[role="_abstract"]
 You can create virtual machines (VMs) from the command line by editing or creating a `VirtualMachine` manifest. You can simplify VM configuration by using an xref:../../../virt/creating_vm/virt-creating-vms-from-instance-types.adoc#virt-creating-vms-from-instance-types[instance type] in your VM manifest.
 
 [NOTE]
@@ -14,6 +15,7 @@ You can also xref:../../../virt/creating_vm/virt-creating-vms-from-instance-type
 ====
 
 include::modules/virt-creating-vm-cli.adoc[leveloffset=+1]
+include::modules/virt-supported-custom-video-devices.adoc[leveloffset=+2]
 
 .Next steps