OvmfPkg/CloudHv/README

   1
   2 CloudHv is a port of OVMF for the Cloud Hypervisor project.
   3
   4 The Cloud Hypervisor project
   5 ----------------------------
   6
   7 Cloud Hypervisor is a Virtual Machine Monitor that runs on top of KVM. The
   8 project focuses on exclusively running modern, cloud workloads, on top of a
   9 limited set of hardware architectures and platforms. Cloud workloads refers to
  10 those that are usually run by customers inside a cloud provider. This means
  11 modern operating systems with most I/O handled by paravirtualised devices
  12 (i.e. virtio), no requirement for legacy devices, and 64-bit CPUs.
  13
  14 https://github.com/cloud-hypervisor/cloud-hypervisor
  15
  16 Design
  17 ------
  18
  19 Based on Cloud Hypervisor's motto to reduce the emulation as much as possible,
  20 the project logically decided to support the PVH boot specification as the only
  21 way of booting virtual machines. That includes both direct kernel boot and OVMF
  22 firmware which must be generated as PVH ELF binaries.
  23 PVH allows information like location of ACPI tables and location of guest RAM
  24 ranges to be shared without the need of an extra emulated device like a CMOS.
  25
  26 Features
  27 --------
  28
  29 * Serial console
  30 * EFI shell
  31 * virtio-pci
  32
  33 Build
  34 -----
  35
  36 The way to build the CloudHv target is as follows:
  37
  38 OvmfPkg/build.sh -p OvmfPkg/CloudHv/CloudHvX64.dsc -a X64 -b DEBUG
  39
  40 Usage
  41 -----
  42
  43 Assuming Cloud Hypervisor is already built, one can start a virtual machine as
  44 follows:
  45
  46 ./cloud-hypervisor \
  47     --cpus boot=1 \
  48     --memory size=1G \
  49     --kernel Build/CloudHvX64/DEBUG_GCC5/FV/CLOUDHV.fd \
  50     --disk path=/path/to/disk.raw
  51
  52 Releases
  53 --------
  54
  55 In edk2-stable202202, CloudHv is generated as data-only binary.
  56 Starting with edk2-stable202205, CloudHv is generated as a PVH ELF binary to
  57 reduce the amount of emulation needed from Cloud Hypervisor.
  58 For TDX, things are handled differently and PVH is not used, which is why the
  59 firmware is always generated as a data-only binary.
  60
  61 +-------------------+----------------+
  62 |                   |    CloudHv     |
  63 +-------------------+----------------+
  64 | edk2-stable202202 | Data binary    |
  65 +-------------------+----------------+
  66 | edk2-stable202205 | PVH ELF binary |
  67 +-------------------+----------------+