xref: /openbmc/qemu/docs/about/build-platforms.rst (revision 646b5378)
1.. _Supported-build-platforms:
2
3Supported build platforms
4=========================
5
6QEMU aims to support building and executing on multiple host OS
7platforms. This appendix outlines which platforms are the major build
8targets. These platforms are used as the basis for deciding upon the
9minimum required versions of 3rd party software QEMU depends on. The
10supported platforms are the targets for automated testing performed by
11the project when patches are submitted for review, and tested before and
12after merge.
13
14If a platform is not listed here, it does not imply that QEMU won't
15work. If an unlisted platform has comparable software versions to a
16listed platform, there is every expectation that it will work. Bug
17reports are welcome for problems encountered on unlisted platforms
18unless they are clearly older vintage than what is described here.
19
20Note that when considering software versions shipped in distros as
21support targets, QEMU considers only the version number, and assumes the
22features in that distro match the upstream release with the same
23version. In other words, if a distro backports extra features to the
24software in their distro, QEMU upstream code will not add explicit
25support for those backports, unless the feature is auto-detectable in a
26manner that works for the upstream releases too.
27
28The `Repology`_ site is a useful resource to identify
29currently shipped versions of software in various operating systems,
30though it does not cover all distros listed below.
31
32Supported host architectures
33----------------------------
34
35Those hosts are officially supported, with various accelerators:
36
37  .. list-table::
38   :header-rows: 1
39
40   * - CPU Architecture
41     - Accelerators
42   * - Arm
43     - kvm (64 bit only), tcg, xen
44   * - MIPS (64 bit little endian only)
45     - kvm, tcg
46   * - PPC
47     - kvm, tcg
48   * - RISC-V
49     - kvm, tcg
50   * - s390x
51     - kvm, tcg
52   * - SPARC
53     - tcg
54   * - x86
55     - hvf (64 bit only), kvm, nvmm, tcg, whpx (64 bit only), xen
56
57Other host architectures are not supported. It is possible to build QEMU system
58emulation on an unsupported host architecture using the configure
59``--enable-tcg-interpreter`` option to enable the TCI support, but note that
60this is very slow and is not recommended for normal use. QEMU user emulation
61requires host-specific support for signal handling, therefore TCI won't help
62on unsupported host architectures.
63
64Non-supported architectures may be removed in the future following the
65:ref:`deprecation process<Deprecated features>`.
66
67Linux OS, macOS, FreeBSD, NetBSD, OpenBSD
68-----------------------------------------
69
70The project aims to support the most recent major version at all times for
71up to five years after its initial release. Support
72for the previous major version will be dropped 2 years after the new major
73version is released or when the vendor itself drops support, whichever comes
74first. In this context, third-party efforts to extend the lifetime of a distro
75are not considered, even when they are endorsed by the vendor (eg. Debian LTS);
76the same is true of repositories that contain packages backported from later
77releases (e.g. Debian backports). Within each major release, only the most
78recent minor release is considered.
79
80For the purposes of identifying supported software versions available on Linux,
81the project will look at CentOS, Debian, Fedora, openSUSE, RHEL, SLES and
82Ubuntu LTS. Other distros will be assumed to ship similar software versions.
83
84For FreeBSD and OpenBSD, decisions will be made based on the contents of the
85respective ports repository, while NetBSD will use the pkgsrc repository.
86
87For macOS, `Homebrew`_ will be used, although `MacPorts`_ is expected to carry
88similar versions.
89
90Some build dependencies may follow less conservative rules:
91
92Python runtime
93  Distributions with long-term support often provide multiple versions
94  of the Python runtime.  While QEMU will initially aim to support the
95  distribution's default runtime, it may later increase its minimum version
96  to any newer python that is available as an option from the vendor.
97  In this case, it will be necessary to use the ``--python`` command line
98  option of the ``configure`` script to point QEMU to a supported
99  version of the Python runtime.
100
101  As of QEMU |version|, the minimum supported version of Python is 3.7.
102
103Python build dependencies
104  Some of QEMU's build dependencies are written in Python.  Usually these
105  are only packaged by distributions for the default Python runtime.
106  If QEMU bumps its minimum Python version and a non-default runtime is
107  required, it may be necessary to fetch python modules from the Python
108  Package Index (PyPI) via ``pip``, in order to build QEMU.
109
110Optional build dependencies
111  Build components whose absence does not affect the ability to build
112  QEMU may not be available in distros, or may be too old for QEMU's
113  requirements.  Many of these, such as the Avocado testing framework
114  or various linters, are written in Python and therefore can also
115  be installed using ``pip``.  Cross compilers are another example
116  of optional build-time dependency; in this case it is possible to
117  download them from repositories such as EPEL, to use container-based
118  cross compilation using ``docker`` or ``podman``, or to use pre-built
119  binaries distributed with QEMU.
120
121
122Windows
123-------
124
125The project aims to support the two most recent versions of Windows that are
126still supported by the vendor. The minimum Windows API that is currently
127targeted is "Windows 8", so theoretically the QEMU binaries can still be run
128on older versions of Windows, too. However, such old versions of Windows are
129not tested anymore, so it is recommended to use one of the latest versions of
130Windows instead.
131
132The project supports building QEMU with current versions of the MinGW
133toolchain, either hosted on Linux (Debian/Fedora) or via `MSYS2`_ on Windows.
134A more recent Windows version is always preferred as it is less likely to have
135problems with building via MSYS2. The building process of QEMU involves some
136Python scripts that call os.symlink() which needs special attention for the
137build process to successfully complete. On newer versions of Windows 10,
138unprivileged accounts can create symlinks if Developer Mode is enabled.
139When Developer Mode is not available/enabled, the SeCreateSymbolicLinkPrivilege
140privilege is required, or the process must be run as an administrator.
141
142Only 64-bit Windows is supported.
143
144.. _Homebrew: https://brew.sh/
145.. _MacPorts: https://www.macports.org/
146.. _MSYS2: https://www.msys2.org/
147.. _Repology: https://repology.org/
148