+++ /dev/null
-@node Deprecated features
-@appendix Deprecated features
-
-In general features are intended to be supported indefinitely once
-introduced into QEMU. In the event that a feature needs to be removed,
-it will be listed in this appendix. The feature will remain functional
-for 2 releases prior to actual removal. Deprecated features may also
-generate warnings on the console when QEMU starts up, or if activated
-via a monitor command, however, this is not a mandatory requirement.
-
-Prior to the 2.10.0 release there was no official policy on how
-long features would be deprecated prior to their removal, nor
-any documented list of which features were deprecated. Thus
-any features deprecated prior to 2.10.0 will be treated as if
-they were first deprecated in the 2.10.0 release.
-
-What follows is a list of all features currently marked as
-deprecated.
-
-@section System emulator command line arguments
-
-@subsection -machine enforce-config-section=on|off (since 3.1)
-
-The @option{enforce-config-section} parameter is replaced by the
-@option{-global migration.send-configuration=@var{on|off}} option.
-
-@subsection -no-kvm (since 1.3.0)
-
-The ``-no-kvm'' argument is now a synonym for setting ``-accel tcg''.
-
-@subsection -usbdevice (since 2.10.0)
-
-The ``-usbdevice DEV'' argument is now a synonym for setting
-the ``-device usb-DEV'' argument instead. The deprecated syntax
-would automatically enable USB support on the machine type.
-If using the new syntax, USB support must be explicitly
-enabled via the ``-machine usb=on'' argument.
-
-@subsection -drive file=json:@{...@{'driver':'file'@}@} (since 3.0)
-
-The 'file' driver for drives is no longer appropriate for character or host
-devices and will only accept regular files (S_IFREG). The correct driver
-for these file types is 'host_cdrom' or 'host_device' as appropriate.
-
-@subsection -net ...,name=@var{name} (since 3.1)
-
-The @option{name} parameter of the @option{-net} option is a synonym
-for the @option{id} parameter, which should now be used instead.
-
-@subsection -smp (invalid topologies) (since 3.1)
-
-CPU topology properties should describe whole machine topology including
-possible CPUs.
-
-However, historically it was possible to start QEMU with an incorrect topology
-where @math{@var{n} <= @var{sockets} * @var{cores} * @var{threads} < @var{maxcpus}},
-which could lead to an incorrect topology enumeration by the guest.
-Support for invalid topologies will be removed, the user must ensure
-topologies described with -smp include all possible cpus, i.e.
- @math{@var{sockets} * @var{cores} * @var{threads} = @var{maxcpus}}.
-
-@subsection -vnc acl (since 4.0.0)
-
-The @code{acl} option to the @code{-vnc} argument has been replaced
-by the @code{tls-authz} and @code{sasl-authz} options.
-
-@subsection QEMU_AUDIO_ environment variables and -audio-help (since 4.0)
-
-The ``-audiodev'' argument is now the preferred way to specify audio
-backend settings instead of environment variables. To ease migration to
-the new format, the ``-audiodev-help'' option can be used to convert
-the current values of the environment variables to ``-audiodev'' options.
-
-@subsection Creating sound card devices and vnc without audiodev= property (since 4.2)
-
-When not using the deprecated legacy audio config, each sound card
-should specify an @code{audiodev=} property. Additionally, when using
-vnc, you should specify an @code{audiodev=} propery if you plan to
-transmit audio through the VNC protocol.
-
-@subsection -mon ...,control=readline,pretty=on|off (since 4.1)
-
-The @code{pretty=on|off} switch has no effect for HMP monitors, but is
-silently ignored. Using the switch with HMP monitors will become an
-error in the future.
-
-@subsection -realtime (since 4.1)
-
-The @code{-realtime mlock=on|off} argument has been replaced by the
-@code{-overcommit mem-lock=on|off} argument.
-
-@subsection -numa node,mem=@var{size} (since 4.1)
-
-The parameter @option{mem} of @option{-numa node} is used to assign a part of
-guest RAM to a NUMA node. But when using it, it's impossible to manage specified
-RAM chunk on the host side (like bind it to a host node, setting bind policy, ...),
-so guest end-ups with the fake NUMA configuration with suboptiomal performance.
-However since 2014 there is an alternative way to assign RAM to a NUMA node
-using parameter @option{memdev}, which does the same as @option{mem} and adds
-means to actualy manage node RAM on the host side. Use parameter @option{memdev}
-with @var{memory-backend-ram} backend as an replacement for parameter @option{mem}
-to achieve the same fake NUMA effect or a properly configured
-@var{memory-backend-file} backend to actually benefit from NUMA configuration.
-In future new machine versions will not accept the option but it will still
-work with old machine types. User can check QAPI schema to see if the legacy
-option is supported by looking at MachineInfo::numa-mem-supported property.
-
-@subsection -numa node (without memory specified) (since 4.1)
-
-Splitting RAM by default between NUMA nodes has the same issues as @option{mem}
-parameter described above with the difference that the role of the user plays
-QEMU using implicit generic or board specific splitting rule.
-Use @option{memdev} with @var{memory-backend-ram} backend or @option{mem} (if
-it's supported by used machine type) to define mapping explictly instead.
-
-@subsection -mem-path fallback to RAM (since 4.1)
-Currently if guest RAM allocation from file pointed by @option{mem-path}
-fails, QEMU falls back to allocating from RAM, which might result
-in unpredictable behavior since the backing file specified by the user
-is ignored. In the future, users will be responsible for making sure
-the backing storage specified with @option{-mem-path} can actually provide
-the guest RAM configured with @option{-m} and QEMU will fail to start up if
-RAM allocation is unsuccessful.
-
-@subsection RISC-V -bios (since 4.1)
-
-QEMU 4.1 introduced support for the -bios option in QEMU for RISC-V for the
-RISC-V virt machine and sifive_u machine.
-
-QEMU 4.1 has no changes to the default behaviour to avoid breakages. This
-default will change in a future QEMU release, so please prepare now. All users
-of the virt or sifive_u machine must change their command line usage.
-
-QEMU 4.1 has three options, please migrate to one of these three:
- 1. ``-bios none`` - This is the current default behavior if no -bios option
- is included. QEMU will not automatically load any firmware. It is up
- to the user to load all the images they need.
- 2. ``-bios default`` - In a future QEMU release this will become the default
- behaviour if no -bios option is specified. This option will load the
- default OpenSBI firmware automatically. The firmware is included with
- the QEMU release and no user interaction is required. All a user needs
- to do is specify the kernel they want to boot with the -kernel option
- 3. ``-bios <file>`` - Tells QEMU to load the specified file as the firmwrae.
-
-@subsection -tb-size option (since 5.0)
-
-QEMU 5.0 introduced an alternative syntax to specify the size of the translation
-block cache, @option{-accel tcg,tb-size=}. The new syntax deprecates the
-previously available @option{-tb-size} option.
-
-@subsection -show-cursor option (since 5.0)
-
-Use @option{-display sdl,show-cursor=on} or
- @option{-display gtk,show-cursor=on} instead.
-
-@section QEMU Machine Protocol (QMP) commands
-
-@subsection change (since 2.5.0)
-
-Use ``blockdev-change-medium'' or ``change-vnc-password'' instead.
-
-@subsection migrate_set_downtime and migrate_set_speed (since 2.8.0)
-
-Use ``migrate-set-parameters'' instead.
-
-@subsection migrate-set-cache-size and query-migrate-cache-size (since 2.11.0)
-
-Use ``migrate-set-parameters'' and ``query-migrate-parameters'' instead.
-
-@subsection query-block result field dirty-bitmaps[i].status (since 4.0)
-
-The ``status'' field of the ``BlockDirtyInfo'' structure, returned by
-the query-block command is deprecated. Two new boolean fields,
-``recording'' and ``busy'' effectively replace it.
-
-@subsection query-block result field dirty-bitmaps (Since 4.2)
-
-The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
-the query-block command is itself now deprecated. The ``dirty-bitmaps``
-field of the ``BlockDeviceInfo`` struct should be used instead, which is the
-type of the ``inserted`` field in query-block replies, as well as the
-type of array items in query-named-block-nodes.
-
-Since the ``dirty-bitmaps`` field is optionally present in both the old and
-new locations, clients must use introspection to learn where to anticipate
-the field if/when it does appear in command output.
-
-@subsection query-cpus (since 2.12.0)
-
-The ``query-cpus'' command is replaced by the ``query-cpus-fast'' command.
-
-@subsection query-cpus-fast "arch" output member (since 3.0.0)
-
-The ``arch'' output member of the ``query-cpus-fast'' command is
-replaced by the ``target'' output member.
-
-@subsection cpu-add (since 4.0)
-
-Use ``device_add'' for hotplugging vCPUs instead of ``cpu-add''. See
-documentation of ``query-hotpluggable-cpus'' for additional
-details.
-
-@subsection query-events (since 4.0)
-
-The ``query-events'' command has been superseded by the more powerful
-and accurate ``query-qmp-schema'' command.
-
-@subsection chardev client socket with 'wait' option (since 4.0)
-
-Character devices creating sockets in client mode should not specify
-the 'wait' field, which is only applicable to sockets in server mode
-
-@section Human Monitor Protocol (HMP) commands
-
-@subsection The hub_id parameter of 'hostfwd_add' / 'hostfwd_remove' (since 3.1)
-
-The @option{[hub_id name]} parameter tuple of the 'hostfwd_add' and
-'hostfwd_remove' HMP commands has been replaced by @option{netdev_id}.
-
-@subsection cpu-add (since 4.0)
-
-Use ``device_add'' for hotplugging vCPUs instead of ``cpu-add''. See
-documentation of ``query-hotpluggable-cpus'' for additional details.
-
-@subsection acl_show, acl_reset, acl_policy, acl_add, acl_remove (since 4.0.0)
-
-The ``acl_show'', ``acl_reset'', ``acl_policy'', ``acl_add'', and
-``acl_remove'' commands are deprecated with no replacement. Authorization
-for VNC should be performed using the pluggable QAuthZ objects.
-
-@section Guest Emulator ISAs
-
-@subsection RISC-V ISA privledge specification version 1.09.1 (since 4.1)
-
-The RISC-V ISA privledge specification version 1.09.1 has been deprecated.
-QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
-should be used instead of the 1.09.1 version.
-
-@section System emulator CPUS
-
-@subsection RISC-V ISA CPUs (since 4.1)
-
-The RISC-V cpus with the ISA version in the CPU name have been depcreated. The
-four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
-``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
-option when using the ``rv32`` or ``rv64`` CPUs.
-
-@subsection RISC-V ISA CPUs (since 4.1)
-
-The RISC-V no MMU cpus have been depcreated. The two CPUs: ``rv32imacu-nommu`` and
-``rv64imacu-nommu`` should no longer be used. Instead the MMU status can be specified
-via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
-
-@section System emulator devices
-
-@subsection ide-drive (since 4.2)
-
-The 'ide-drive' device is deprecated. Users should use 'ide-hd' or
-'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
-
-@subsection scsi-disk (since 4.2)
-
-The 'scsi-disk' device is deprecated. Users should use 'scsi-hd' or
-'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
-
-@section System emulator machines
-
-@subsection mips r4k platform (since 5.0)
-
-This machine type is very old and unmaintained. Users should use the 'malta'
-machine type instead.
-
-@subsection pc-1.0, pc-1.1, pc-1.2 and pc-1.3 (since 5.0)
-
-These machine types are very old and likely can not be used for live migration
-from old QEMU versions anymore. A newer machine type should be used instead.
-
-@subsection spike_v1.9.1 and spike_v1.10 (since 4.1)
-
-The version specific Spike machines have been deprecated in favour of the
-generic ``spike`` machine. If you need to specify an older version of the RISC-V
-spec you can use the ``-cpu rv64gcsu,priv_spec=v1.9.1`` command line argument.
-
-@section Device options
-
-@subsection Emulated device options
-
-@subsubsection -device virtio-blk,scsi=on|off (since 5.0.0)
-
-The virtio-blk SCSI passthrough feature is a legacy VIRTIO feature. VIRTIO 1.0
-and later do not support it because the virtio-scsi device was introduced for
-full SCSI support. Use virtio-scsi instead when SCSI passthrough is required.
-
-Note this also applies to ``-device virtio-blk-pci,scsi=on|off'', which is an
-alias.
-
-@subsection Block device options
-
-@subsubsection "backing": "" (since 2.12.0)
-
-In order to prevent QEMU from automatically opening an image's backing
-chain, use ``"backing": null'' instead.
-
-@subsubsection rbd keyvalue pair encoded filenames: "" (since 3.1.0)
-
-Options for ``rbd'' should be specified according to its runtime options,
-like other block drivers. Legacy parsing of keyvalue pair encoded
-filenames is useful to open images with the old format for backing files;
-These image files should be updated to use the current format.
-
-Example of legacy encoding:
-
-@code{json:@{"file.driver":"rbd", "file.filename":"rbd:rbd/name"@}}
-
-The above, converted to the current supported format:
-
-@code{json:@{"file.driver":"rbd", "file.pool":"rbd", "file.image":"name"@}}
-
-@section Related binaries
-
-@subsection qemu-img convert -n -o (since 4.2.0)
-
-All options specified in @option{-o} are image creation options, so
-they have no effect when used with @option{-n} to skip image creation.
-Silently ignored options can be confusing, so this combination of
-options will be made an error in future versions.
-
-@section Backwards compatibility
-
-@subsection Runnability guarantee of CPU models (since 4.1.0)
-
-Previous versions of QEMU never changed existing CPU models in
-ways that introduced additional host software or hardware
-requirements to the VM. This allowed management software to
-safely change the machine type of an existing VM without
-introducing new requirements ("runnability guarantee"). This
-prevented CPU models from being updated to include CPU
-vulnerability mitigations, leaving guests vulnerable in the
-default configuration.
-
-The CPU model runnability guarantee won't apply anymore to
-existing CPU models. Management software that needs runnability
-guarantees must resolve the CPU model aliases using te
-``alias-of'' field returned by the ``query-cpu-definitions'' QMP
-command.
-
-While those guarantees are kept, the return value of
-``query-cpu-definitions'' will have existing CPU model aliases
-point to a version that doesn't break runnability guarantees
-(specifically, version 1 of those CPU models). In future QEMU
-versions, aliases will point to newer CPU model versions
-depending on the machine type, so management software must
-resolve CPU model aliases before starting a virtual machine.
-
-
-@node Recently removed features
-@appendix Recently removed features
-
-What follows is a record of recently removed, formerly deprecated
-features that serves as a record for users who have encountered
-trouble after a recent upgrade.
-
-@section QEMU Machine Protocol (QMP) commands
-
-@subsection block-dirty-bitmap-add "autoload" parameter (since 4.2.0)
-
-The "autoload" parameter has been ignored since 2.12.0. All bitmaps
-are automatically loaded from qcow2 images.
-
-@section Related binaries
-
-@subsection qemu-nbd --partition (removed in 5.0.0)
-
-The ``qemu-nbd --partition $digit'' code (also spelled @option{-P})
-could only handle MBR partitions, and never correctly handled logical
-partitions beyond partition 5. Exporting a partition can still be
-done by utilizing the @option{--image-opts} option with a raw blockdev
-using the @code{offset} and @code{size} parameters layered on top of
-any other existing blockdev. For example, if partition 1 is 100MiB
-long starting at 1MiB, the old command:
-
-@code{qemu-nbd -t -P 1 -f qcow2 file.qcow2}
-
-can be rewritten as:
-
-@code{qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2}
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