xref: /openbmc/qemu/docs/about/build-platforms.rst (revision f2b90109)
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 (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     - hax, 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. Support
71for the previous major version will be dropped 2 years after the new major
72version is released or when the vendor itself drops support, whichever comes
73first. In this context, third-party efforts to extend the lifetime of a distro
74are not considered, even when they are endorsed by the vendor (eg. Debian LTS);
75the same is true of repositories that contain packages backported from later
76releases (e.g. Debian backports). Within each major release, only the most
77recent minor release is considered.
78
79For the purposes of identifying supported software versions available on Linux,
80the project will look at CentOS, Debian, Fedora, openSUSE, RHEL, SLES and
81Ubuntu LTS. Other distros will be assumed to ship similar software versions.
82
83For FreeBSD and OpenBSD, decisions will be made based on the contents of the
84respective ports repository, while NetBSD will use the pkgsrc repository.
85
86For macOS, `Homebrew`_ will be used, although `MacPorts`_ is expected to carry
87similar versions.
88
89Some build dependencies may follow less conservative rules:
90
91Python runtime
92  Distributions with long-term support often provide multiple versions
93  of the Python runtime.  While QEMU will initially aim to support the
94  distribution's default runtime, it may later increase its minimum version
95  to any newer python that is available as an option from the vendor.
96  In this case, it will be necessary to use the ``--python`` command line
97  option of the ``configure`` script to point QEMU to a supported
98  version of the Python runtime.
99
100  As of QEMU |version|, the minimum supported version of Python is 3.6.
101
102Python build dependencies
103  Some of QEMU's build dependencies are written in Python.  Usually these
104  are only packaged by distributions for the default Python runtime.
105  If QEMU bumps its minimum Python version and a non-default runtime is
106  required, it may be necessary to fetch python modules from the Python
107  Package Index (PyPI) via ``pip``, in order to build QEMU.
108
109Optional build dependencies
110  Build components whose absence does not affect the ability to build
111  QEMU may not be available in distros, or may be too old for QEMU's
112  requirements.  Many of these, such as the Avocado testing framework
113  or various linters, are written in Python and therefore can also
114  be installed using ``pip``.  Cross compilers are another example
115  of optional build-time dependency; in this case it is possible to
116  download them from repositories such as EPEL, to use container-based
117  cross compilation using ``docker`` or ``podman``, or to use pre-built
118  binaries distributed with QEMU.
119
120
121Windows
122-------
123
124The project aims to support the two most recent versions of Windows that are
125still supported by the vendor. The minimum Windows API that is currently
126targeted is "Windows 8", so theoretically the QEMU binaries can still be run
127on older versions of Windows, too. However, such old versions of Windows are
128not tested anymore, so it is recommended to use one of the latest versions of
129Windows instead.
130
131The project supports building QEMU with current versions of the MinGW
132toolchain, either hosted on Linux (Debian/Fedora) or via `MSYS2`_ on Windows.
133A more recent Windows version is always preferred as it is less likely to have
134problems with building via MSYS2. The building process of QEMU involves some
135Python scripts that call os.symlink() which needs special attention for the
136build process to successfully complete. On newer versions of Windows 10,
137unprivileged accounts can create symlinks if Developer Mode is enabled.
138When Developer Mode is not available/enabled, the SeCreateSymbolicLinkPrivilege
139privilege is required, or the process must be run as an administrator.
140
141.. _Homebrew: https://brew.sh/
142.. _MacPorts: https://www.macports.org/
143.. _MSYS2: https://www.msys2.org/
144.. _Repology: https://repology.org/
145