docs/devel/kconfig.rst

13 SCSI adapters.  Arm, s390 and x86 boards can all present a virtio-blk
21 QEMU uses a simple domain-specific language to describe the dependencies
24 * new targets and boards can be added without knowing in detail the
30 * users can easily build reduced versions of QEMU that support only a subset
32   all emulated PCI devices that QEMU supports, but the build process is
36 This domain-specific language is based on the Kconfig language that
41 is instead specified in per-target files under the ``configs/``
48 --------------------
78 include it for clarity and future-proofing.  After ``bool`` the following
136 ------------------------------------
179   a video card might specify ``select EDID`` if it needs to build EDID
199   for example only VFIO (passthrough) and virtio-pci devices.
202   board (and not ones which are very board-specific or that need
231   cannot be started at all without it.  It should be listed under
233   may not be started without it.  Boards default to true, but also
258 --------------------------------------------
261 a file called ``configs/TARGETNAME-softmmu.mak``.  These files
262 initialize some Kconfig variables to non-default values and provide the
267     # Default configuration for alpha-softmmu
278 The first part, consisting of commented-out ``=n`` assignments, tells
286 ``--without-default-devices`` option.  When this is done, everything defaults
295 and/or pick a subset of the devices in those device groups.  Without
297 without default devices might not do much more than start an empty
298 machine, and even then only if ``--nodefaults`` is specified on the
299 command line.  Starting a VM *without* ``--nodefaults`` is allowed to
301 ``--without-default-devices`` are considered bugs in the test code:
302 the tests should either use ``--nodefaults``, and should be skipped
303 if a necessary device is not present in the build.  Such failures
312 ----------------
315 that are detected by QEMU's configure or ``meson.build`` scripts; for
324 and also listed as follows in the top-level meson.build's host_kconfig