---
features:
  - |
    Added support for Hyper-V VMs with UEFI Secure Boot enabled.
    In order to create such VMs, there are a couple of things to consider:

    * Images should be prepared for Generation 2 VMs. The image property
      "hw_machine_type=hyperv-gen2" is mandatory.
    * The guest OS type must be specified in order to properly spawn the VMs.
      It can be specified through the image property "os_type", and the
      acceptable values are "windows" or "linux".
    * The UEFI Secure Boot feature can be requested through the image property
      "os_secure_boot" (acceptable values: "disabled", "optional", "required")
      or flavor extra spec "os:secure_boot" (acceptable values: "disabled",
      "required"). The flavor extra spec will take precedence. If the image
      property and the flavor extra spec values are conflicting, then an
      exception is raised.
    * This feature is supported on Windows / Hyper-V Server 2012 R2 for
      Windows guests, and Windows / Hyper-V Server 2016 for both
      Windows and Linux guests.