4 QEMU is a generic and open source machine & userspace emulator and
7 QEMU is capable of emulating a complete machine in software without any
8 need for hardware virtualization support. By using dynamic translation,
9 it achieves very good performance. QEMU can also integrate with the Xen
10 and KVM hypervisors to provide emulated hardware while allowing the
11 hypervisor to manage the CPU. With hypervisor support, QEMU can achieve
12 near native performance for CPUs. When QEMU emulates CPUs directly it is
13 capable of running operating systems made for one machine (e.g. an ARMv7
14 board) on a different machine (e.g. an x86_64 PC board).
16 QEMU is also capable of providing userspace API virtualization for Linux
17 and BSD kernel interfaces. This allows binaries compiled against one
18 architecture ABI (e.g. the Linux PPC64 ABI) to be run on a host using a
19 different architecture ABI (e.g. the Linux x86_64 ABI). This does not
20 involve any hardware emulation, simply CPU and syscall emulation.
22 QEMU aims to fit into a variety of use cases. It can be invoked directly
23 by users wishing to have full control over its behaviour and settings.
24 It also aims to facilitate integration into higher level management
25 layers, by providing a stable command line interface and monitor API.
26 It is commonly invoked indirectly via the libvirt library when using
27 open source applications such as oVirt, OpenStack and virt-manager.
29 QEMU as a whole is released under the GNU General Public License,
30 version 2. For full licensing details, consult the LICENSE file.
36 QEMU is multi-platform software intended to be buildable on all modern
37 Linux platforms, OS-X, Win32 (via the Mingw64 toolchain) and a variety
38 of other UNIX targets. The simple steps to build QEMU are:
45 Additional information can also be found online via the QEMU website:
47 https://qemu.org/Hosts/Linux
48 https://qemu.org/Hosts/Mac
49 https://qemu.org/Hosts/W32
55 The QEMU source code is maintained under the GIT version control system.
57 git clone git://git.qemu.org/qemu.git
59 When submitting patches, one common approach is to use 'git
60 format-patch' and/or 'git send-email' to format & send the mail to the
61 qemu-devel@nongnu.org mailing list. All patches submitted must contain
62 a 'Signed-off-by' line from the author. Patches should follow the
63 guidelines set out in the HACKING and CODING_STYLE files.
65 Additional information on submitting patches can be found online via
68 https://qemu.org/Contribute/SubmitAPatch
69 https://qemu.org/Contribute/TrivialPatches
71 The QEMU website is also maintained under source control.
73 git clone git://git.qemu.org/qemu-web.git
74 https://www.qemu.org/2017/02/04/the-new-qemu-website-is-up/
76 A 'git-publish' utility was created to make above process less
77 cumbersome, and is highly recommended for making regular contributions,
78 or even just for sending consecutive patch series revisions. It also
79 requires a working 'git send-email' setup, and by default doesn't
80 automate everything, so you may want to go through the above steps
83 For installation instructions, please go to
85 https://github.com/stefanha/git-publish
87 The workflow with 'git-publish' is:
89 $ git checkout master -b my-feature
90 $ # work on new commits, add your 'Signed-off-by' lines to each
93 Your patch series will be sent and tagged as my-feature-v1 if you need to refer
94 back to it in the future.
98 $ git checkout my-feature # same topic branch
99 $ # making changes to the commits (using 'git rebase', for example)
102 Your patch series will be sent with 'v2' tag in the subject and the git tip
103 will be tagged as my-feature-v2.
108 The QEMU project uses Launchpad as its primary upstream bug tracker. Bugs
109 found when running code built from QEMU git or upstream released sources
110 should be reported via:
112 https://bugs.launchpad.net/qemu/
114 If using QEMU via an operating system vendor pre-built binary package, it
115 is preferable to report bugs to the vendor's own bug tracker first. If
116 the bug is also known to affect latest upstream code, it can also be
117 reported via launchpad.
119 For additional information on bug reporting consult:
121 https://qemu.org/Contribute/ReportABug
127 The QEMU community can be contacted in a number of ways, with the two
128 main methods being email and IRC
130 - qemu-devel@nongnu.org
131 https://lists.nongnu.org/mailman/listinfo/qemu-devel
132 - #qemu on irc.oftc.net
134 Information on additional methods of contacting the community can be
135 found online via the QEMU website:
137 https://qemu.org/Contribute/StartHere