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+@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 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}