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removed-features.rst (30363B)


      1 
      2 Removed features
      3 ================
      4 
      5 What follows is a record of recently removed, formerly deprecated
      6 features that serves as a record for users who have encountered
      7 trouble after a recent upgrade.
      8 
      9 System emulator command line arguments
     10 --------------------------------------
     11 
     12 ``-hdachs`` (removed in 2.12)
     13 '''''''''''''''''''''''''''''
     14 
     15 The geometry defined by ``-hdachs c,h,s,t`` should now be specified via
     16 ``-device ide-hd,drive=dr,cyls=c,heads=h,secs=s,bios-chs-trans=t``
     17 (together with ``-drive if=none,id=dr,...``).
     18 
     19 ``-net channel`` (removed in 2.12)
     20 ''''''''''''''''''''''''''''''''''
     21 
     22 This option has been replaced by ``-net user,guestfwd=...``.
     23 
     24 ``-net dump`` (removed in 2.12)
     25 '''''''''''''''''''''''''''''''
     26 
     27 ``-net dump[,vlan=n][,file=filename][,len=maxlen]`` has been replaced by
     28 ``-object filter-dump,id=id,netdev=dev[,file=filename][,maxlen=maxlen]``.
     29 Note that the new syntax works with netdev IDs instead of the old "vlan" hubs.
     30 
     31 ``-no-kvm-pit`` (removed in 2.12)
     32 '''''''''''''''''''''''''''''''''
     33 
     34 This was just a dummy option that has been ignored, since the in-kernel PIT
     35 cannot be disabled separately from the irqchip anymore. A similar effect
     36 (which also disables the KVM IOAPIC) can be obtained with
     37 ``-M kernel_irqchip=split``.
     38 
     39 ``-tdf`` (removed in 2.12)
     40 ''''''''''''''''''''''''''
     41 
     42 There is no replacement, the ``-tdf`` option has just been ignored since the
     43 behaviour that could be changed by this option in qemu-kvm is now the default
     44 when using the KVM PIT. It still can be requested explicitly using
     45 ``-global kvm-pit.lost_tick_policy=delay``.
     46 
     47 ``-drive secs=s``, ``-drive heads=h`` & ``-drive cyls=c`` (removed in 3.0)
     48 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
     49 
     50 The drive geometry should now be specified via
     51 ``-device ...,drive=dr,cyls=c,heads=h,secs=s`` (together with
     52 ``-drive if=none,id=dr,...``).
     53 
     54 ``-drive serial=``, ``-drive trans=`` & ``-drive addr=`` (removed in 3.0)
     55 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
     56 
     57 Use ``-device ...,drive=dr,serial=r,bios-chs-trans=t,addr=a`` instead
     58 (together with ``-drive if=none,id=dr,...``).
     59 
     60 ``-net ...,vlan=x`` (removed in 3.0)
     61 ''''''''''''''''''''''''''''''''''''
     62 
     63 The term "vlan" was very confusing for most users in this context (it's about
     64 specifying a hub ID, not about IEEE 802.1Q or something similar), so this
     65 has been removed. To connect one NIC frontend with a network backend, either
     66 use ``-nic ...`` (e.g. for on-board NICs) or use ``-netdev ...,id=n`` together
     67 with ``-device ...,netdev=n`` (for full control over pluggable NICs). To
     68 connect multiple NICs or network backends via a hub device (which is what
     69 vlan did), use ``-nic hubport,hubid=x,...`` or
     70 ``-netdev hubport,id=n,hubid=x,...`` (with ``-device ...,netdev=n``) instead.
     71 
     72 ``-no-kvm-irqchip`` (removed in 3.0)
     73 ''''''''''''''''''''''''''''''''''''
     74 
     75 Use ``-machine kernel_irqchip=off`` instead.
     76 
     77 ``-no-kvm-pit-reinjection`` (removed in 3.0)
     78 ''''''''''''''''''''''''''''''''''''''''''''
     79 
     80 Use ``-global kvm-pit.lost_tick_policy=discard`` instead.
     81 
     82 ``-balloon`` (removed in 3.1)
     83 '''''''''''''''''''''''''''''
     84 
     85 The ``-balloon virtio`` option has been replaced by ``-device virtio-balloon``.
     86 The ``-balloon none`` option was a no-op and has no replacement.
     87 
     88 ``-bootp`` (removed in 3.1)
     89 '''''''''''''''''''''''''''
     90 
     91 The ``-bootp /some/file`` argument is replaced by either
     92 ``-netdev user,id=x,bootp=/some/file`` (for pluggable NICs, accompanied with
     93 ``-device ...,netdev=x``), or ``-nic user,bootp=/some/file`` (for on-board NICs).
     94 The new syntax allows different settings to be provided per NIC.
     95 
     96 ``-redir`` (removed in 3.1)
     97 '''''''''''''''''''''''''''
     98 
     99 The ``-redir [tcp|udp]:hostport:[guestaddr]:guestport`` option is replaced
    100 by either ``-netdev
    101 user,id=x,hostfwd=[tcp|udp]:[hostaddr]:hostport-[guestaddr]:guestport``
    102 (for pluggable NICs, accompanied with ``-device ...,netdev=x``) or by the option
    103 ``-nic user,hostfwd=[tcp|udp]:[hostaddr]:hostport-[guestaddr]:guestport``
    104 (for on-board NICs). The new syntax allows different settings to be provided
    105 per NIC.
    106 
    107 ``-smb`` (removed in 3.1)
    108 '''''''''''''''''''''''''
    109 
    110 The ``-smb /some/dir`` argument is replaced by either
    111 ``-netdev user,id=x,smb=/some/dir`` (for pluggable NICs, accompanied with
    112 ``-device ...,netdev=x``), or ``-nic user,smb=/some/dir`` (for on-board NICs).
    113 The new syntax allows different settings to be provided per NIC.
    114 
    115 ``-tftp`` (removed in 3.1)
    116 ''''''''''''''''''''''''''
    117 
    118 The ``-tftp /some/dir`` argument is replaced by either
    119 ``-netdev user,id=x,tftp=/some/dir`` (for pluggable NICs, accompanied with
    120 ``-device ...,netdev=x``), or ``-nic user,tftp=/some/dir`` (for embedded NICs).
    121 The new syntax allows different settings to be provided per NIC.
    122 
    123 ``-localtime`` (removed in 3.1)
    124 '''''''''''''''''''''''''''''''
    125 
    126 Replaced by ``-rtc base=localtime``.
    127 
    128 ``-nodefconfig`` (removed in 3.1)
    129 '''''''''''''''''''''''''''''''''
    130 
    131 Use ``-no-user-config`` instead.
    132 
    133 ``-rtc-td-hack`` (removed in 3.1)
    134 '''''''''''''''''''''''''''''''''
    135 
    136 Use ``-rtc driftfix=slew`` instead.
    137 
    138 ``-startdate`` (removed in 3.1)
    139 '''''''''''''''''''''''''''''''
    140 
    141 Replaced by ``-rtc base=date``.
    142 
    143 ``-vnc ...,tls=...``, ``-vnc ...,x509=...`` & ``-vnc ...,x509verify=...`` (removed in 3.1)
    144 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    145 
    146 The "tls-creds" option should be used instead to point to a "tls-creds-x509"
    147 object created using "-object".
    148 
    149 ``-mem-path`` fallback to RAM (removed in 5.0)
    150 ''''''''''''''''''''''''''''''''''''''''''''''
    151 
    152 If guest RAM allocation from file pointed by ``mem-path`` failed,
    153 QEMU was falling back to allocating from RAM, which might have resulted
    154 in unpredictable behavior since the backing file specified by the user
    155 as ignored. Currently, users are responsible for making sure the backing storage
    156 specified with ``-mem-path`` can actually provide the guest RAM configured with
    157 ``-m`` and QEMU fails to start up if RAM allocation is unsuccessful.
    158 
    159 ``-net ...,name=...`` (removed in 5.1)
    160 ''''''''''''''''''''''''''''''''''''''
    161 
    162 The ``name`` parameter of the ``-net`` option was a synonym
    163 for the ``id`` parameter, which should now be used instead.
    164 
    165 ``-numa node,mem=...`` (removed in 5.1)
    166 '''''''''''''''''''''''''''''''''''''''
    167 
    168 The parameter ``mem`` of ``-numa node`` was used to assign a part of guest RAM
    169 to a NUMA node. But when using it, it's impossible to manage a specified RAM
    170 chunk on the host side (like bind it to a host node, setting bind policy, ...),
    171 so the guest ends up with the fake NUMA configuration with suboptiomal
    172 performance.
    173 However since 2014 there is an alternative way to assign RAM to a NUMA node
    174 using parameter ``memdev``, which does the same as ``mem`` and adds
    175 means to actually manage node RAM on the host side. Use parameter ``memdev``
    176 with *memory-backend-ram* backend as replacement for parameter ``mem``
    177 to achieve the same fake NUMA effect or a properly configured
    178 *memory-backend-file* backend to actually benefit from NUMA configuration.
    179 New machine versions (since 5.1) will not accept the option but it will still
    180 work with old machine types. User can check the QAPI schema to see if the legacy
    181 option is supported by looking at MachineInfo::numa-mem-supported property.
    182 
    183 ``-numa`` node (without memory specified) (removed in 5.2)
    184 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    185 
    186 Splitting RAM by default between NUMA nodes had the same issues as ``mem``
    187 parameter with the difference that the role of the user plays QEMU using
    188 implicit generic or board specific splitting rule.
    189 Use ``memdev`` with *memory-backend-ram* backend or ``mem`` (if
    190 it's supported by used machine type) to define mapping explicitly instead.
    191 Users of existing VMs, wishing to preserve the same RAM distribution, should
    192 configure it explicitly using ``-numa node,memdev`` options. Current RAM
    193 distribution can be retrieved using HMP command ``info numa`` and if separate
    194 memory devices (pc|nv-dimm) are present use ``info memory-device`` and subtract
    195 device memory from output of ``info numa``.
    196 
    197 ``-smp`` (invalid topologies) (removed in 5.2)
    198 ''''''''''''''''''''''''''''''''''''''''''''''
    199 
    200 CPU topology properties should describe whole machine topology including
    201 possible CPUs.
    202 
    203 However, historically it was possible to start QEMU with an incorrect topology
    204 where *n* <= *sockets* * *cores* * *threads* < *maxcpus*,
    205 which could lead to an incorrect topology enumeration by the guest.
    206 Support for invalid topologies is removed, the user must ensure
    207 topologies described with -smp include all possible cpus, i.e.
    208 *sockets* * *cores* * *threads* = *maxcpus*.
    209 
    210 ``-machine enforce-config-section=on|off`` (removed in 5.2)
    211 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    212 
    213 The ``enforce-config-section`` property was replaced by the
    214 ``-global migration.send-configuration={on|off}`` option.
    215 
    216 ``-no-kvm`` (removed in 5.2)
    217 ''''''''''''''''''''''''''''
    218 
    219 The ``-no-kvm`` argument was a synonym for setting ``-machine accel=tcg``.
    220 
    221 ``-realtime`` (removed in 6.0)
    222 ''''''''''''''''''''''''''''''
    223 
    224 The ``-realtime mlock=on|off`` argument has been replaced by the
    225 ``-overcommit mem-lock=on|off`` argument.
    226 
    227 ``-show-cursor`` option (removed in 6.0)
    228 ''''''''''''''''''''''''''''''''''''''''
    229 
    230 Use ``-display sdl,show-cursor=on``, ``-display gtk,show-cursor=on``
    231 or ``-display default,show-cursor=on`` instead.
    232 
    233 ``-tb-size`` option (removed in 6.0)
    234 ''''''''''''''''''''''''''''''''''''
    235 
    236 QEMU 5.0 introduced an alternative syntax to specify the size of the translation
    237 block cache, ``-accel tcg,tb-size=``.
    238 
    239 ``-usbdevice audio`` (removed in 6.0)
    240 '''''''''''''''''''''''''''''''''''''
    241 
    242 This option lacked the possibility to specify an audio backend device.
    243 Use ``-device usb-audio`` now instead (and specify a corresponding USB
    244 host controller or ``-usb`` if necessary).
    245 
    246 ``-vnc acl`` (removed in 6.0)
    247 '''''''''''''''''''''''''''''
    248 
    249 The ``acl`` option to the ``-vnc`` argument has been replaced
    250 by the ``tls-authz`` and ``sasl-authz`` options.
    251 
    252 ``-mon ...,control=readline,pretty=on|off`` (removed in 6.0)
    253 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    254 
    255 The ``pretty=on|off`` switch has no effect for HMP monitors and
    256 its use is rejected.
    257 
    258 ``-drive file=json:{...{'driver':'file'}}`` (removed in 6.0)
    259 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    260 
    261 The 'file' driver for drives is no longer appropriate for character or host
    262 devices and will only accept regular files (S_IFREG). The correct driver
    263 for these file types is 'host_cdrom' or 'host_device' as appropriate.
    264 
    265 Floppy controllers' drive properties (removed in 6.0)
    266 '''''''''''''''''''''''''''''''''''''''''''''''''''''
    267 
    268 Use ``-device floppy,...`` instead.  When configuring onboard floppy
    269 controllers
    270 ::
    271 
    272     -global isa-fdc.driveA=...
    273     -global sysbus-fdc.driveA=...
    274     -global SUNW,fdtwo.drive=...
    275 
    276 become
    277 ::
    278 
    279     -device floppy,unit=0,drive=...
    280 
    281 and
    282 ::
    283 
    284     -global isa-fdc.driveB=...
    285     -global sysbus-fdc.driveB=...
    286 
    287 become
    288 ::
    289 
    290     -device floppy,unit=1,drive=...
    291 
    292 When plugging in a floppy controller
    293 ::
    294 
    295     -device isa-fdc,...,driveA=...
    296 
    297 becomes
    298 ::
    299 
    300     -device isa-fdc,...
    301     -device floppy,unit=0,drive=...
    302 
    303 and
    304 ::
    305 
    306     -device isa-fdc,...,driveB=...
    307 
    308 becomes
    309 ::
    310 
    311     -device isa-fdc,...
    312     -device floppy,unit=1,drive=...
    313 
    314 ``-drive`` with bogus interface type (removed in 6.0)
    315 '''''''''''''''''''''''''''''''''''''''''''''''''''''
    316 
    317 Drives with interface types other than ``if=none`` are for onboard
    318 devices.  Drives the board doesn't pick up can no longer be used with
    319 -device.  Use ``if=none`` instead.
    320 
    321 ``-usbdevice ccid`` (removed in 6.0)
    322 '''''''''''''''''''''''''''''''''''''
    323 
    324 This option was undocumented and not used in the field.
    325 Use ``-device usb-ccid`` instead.
    326 
    327 RISC-V firmware not booted by default (removed in 5.1)
    328 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
    329 
    330 QEMU 5.1 changes the default behaviour from ``-bios none`` to ``-bios default``
    331 for the RISC-V ``virt`` machine and ``sifive_u`` machine.
    332 
    333 ``-no-quit`` (removed in 7.0)
    334 '''''''''''''''''''''''''''''
    335 
    336 The ``-no-quit`` was a synonym for ``-display ...,window-close=off`` which
    337 should be used instead.
    338 
    339 ``--enable-fips`` (removed in 7.1)
    340 ''''''''''''''''''''''''''''''''''
    341 
    342 This option restricted usage of certain cryptographic algorithms when
    343 the host is operating in FIPS mode.
    344 
    345 If FIPS compliance is required, QEMU should be built with the ``libgcrypt``
    346 or ``gnutls`` library enabled as a cryptography provider.
    347 
    348 Neither the ``nettle`` library, or the built-in cryptography provider are
    349 supported on FIPS enabled hosts.
    350 
    351 ``-writeconfig`` (removed in 7.1)
    352 '''''''''''''''''''''''''''''''''
    353 
    354 The ``-writeconfig`` option was not able to serialize the entire contents
    355 of the QEMU command line.  It is thus considered a failed experiment
    356 and removed without a replacement.
    357 
    358 ``loaded`` property of ``secret`` and ``secret_keyring`` objects (removed in 7.1)
    359 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    360 
    361 The ``loaded=on`` option in the command line or QMP ``object-add`` either had
    362 no effect (if ``loaded`` was the last option) or caused options to be
    363 effectively ignored as if they were not given.  The property is therefore
    364 useless and should simply be removed.
    365 
    366 ``opened`` property of ``rng-*`` objects (removed in 7.1)
    367 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    368 
    369 The ``opened=on`` option in the command line or QMP ``object-add`` either had
    370 no effect (if ``opened`` was the last option) or caused errors.  The property
    371 is therefore useless and should simply be removed.
    372 
    373 ``-display sdl,window_close=...`` (removed in 7.1)
    374 ''''''''''''''''''''''''''''''''''''''''''''''''''
    375 
    376 Use ``-display sdl,window-close=...`` instead (i.e. with a minus instead of
    377 an underscore between "window" and "close").
    378 
    379 ``-alt-grab`` and ``-display sdl,alt_grab=on`` (removed in 7.1)
    380 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    381 
    382 Use ``-display sdl,grab-mod=lshift-lctrl-lalt`` instead.
    383 
    384 ``-ctrl-grab`` and ``-display sdl,ctrl_grab=on`` (removed in 7.1)
    385 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    386 
    387 Use ``-display sdl,grab-mod=rctrl`` instead.
    388 
    389 ``-sdl`` (removed in 7.1)
    390 '''''''''''''''''''''''''
    391 
    392 Use ``-display sdl`` instead.
    393 
    394 ``-curses`` (removed in 7.1)
    395 ''''''''''''''''''''''''''''
    396 
    397 Use ``-display curses`` instead.
    398 
    399 Creating sound card devices using ``-soundhw`` (removed in 7.1)
    400 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    401 
    402 Sound card devices should be created using ``-device`` or ``-audio``.
    403 The exception is ``pcspk`` which can be activated using ``-machine
    404 pcspk-audiodev=<name>``.
    405 
    406 ``-watchdog`` (since 7.2)
    407 '''''''''''''''''''''''''
    408 
    409 Use ``-device`` instead.
    410 
    411 
    412 QEMU Machine Protocol (QMP) commands
    413 ------------------------------------
    414 
    415 ``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2)
    416 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    417 
    418 The "autoload" parameter has been ignored since 2.12.0. All bitmaps
    419 are automatically loaded from qcow2 images.
    420 
    421 ``cpu-add`` (removed in 5.2)
    422 ''''''''''''''''''''''''''''
    423 
    424 Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
    425 documentation of ``query-hotpluggable-cpus`` for additional details.
    426 
    427 ``change`` (removed in 6.0)
    428 '''''''''''''''''''''''''''
    429 
    430 Use ``blockdev-change-medium`` or ``change-vnc-password`` or
    431 ``display-update`` instead.
    432 
    433 ``query-events`` (removed in 6.0)
    434 '''''''''''''''''''''''''''''''''
    435 
    436 The ``query-events`` command has been superseded by the more powerful
    437 and accurate ``query-qmp-schema`` command.
    438 
    439 ``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0)
    440 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    441 
    442 Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead.
    443 
    444 ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
    445 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    446 
    447 Use ``migrate_set_parameter`` instead.
    448 
    449 ``query-cpus`` (removed in 6.0)
    450 '''''''''''''''''''''''''''''''
    451 
    452 The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command.
    453 
    454 ``query-cpus-fast`` ``arch`` output member (removed in 6.0)
    455 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    456 
    457 The ``arch`` output member of the ``query-cpus-fast`` command is
    458 replaced by the ``target`` output member.
    459 
    460 chardev client socket with ``wait`` option (removed in 6.0)
    461 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    462 
    463 Character devices creating sockets in client mode should not specify
    464 the 'wait' field, which is only applicable to sockets in server mode
    465 
    466 ``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0)
    467 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    468 
    469 Removed with no replacement.
    470 
    471 ``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0)
    472 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    473 
    474 Removed with no replacement.
    475 
    476 ``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0)
    477 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    478 
    479 The ``status`` field of the ``BlockDirtyInfo`` structure, returned by
    480 these commands is removed. Two new boolean fields, ``recording`` and
    481 ``busy`` effectively replace it.
    482 
    483 ``query-block`` result field ``dirty-bitmaps`` (removed in 6.0)
    484 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    485 
    486 The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
    487 the query-block command is itself now removed. The ``dirty-bitmaps``
    488 field of the ``BlockDeviceInfo`` struct should be used instead, which is the
    489 type of the ``inserted`` field in query-block replies, as well as the
    490 type of array items in query-named-block-nodes.
    491 
    492 ``object-add`` option ``props`` (removed in 6.0)
    493 ''''''''''''''''''''''''''''''''''''''''''''''''
    494 
    495 Specify the properties for the object as top-level arguments instead.
    496 
    497 Human Monitor Protocol (HMP) commands
    498 -------------------------------------
    499 
    500 ``usb_add`` and ``usb_remove`` (removed in 2.12)
    501 ''''''''''''''''''''''''''''''''''''''''''''''''
    502 
    503 Replaced by ``device_add`` and ``device_del`` (use ``device_add help`` for a
    504 list of available devices).
    505 
    506 ``host_net_add`` and ``host_net_remove`` (removed in 2.12)
    507 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    508 
    509 Replaced by ``netdev_add`` and ``netdev_del``.
    510 
    511 The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0)
    512 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    513 
    514 The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and
    515 'hostfwd_remove' HMP commands has been replaced by ``netdev_id``.
    516 
    517 ``cpu-add`` (removed in 5.2)
    518 ''''''''''''''''''''''''''''
    519 
    520 Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
    521 documentation of ``query-hotpluggable-cpus`` for additional details.
    522 
    523 ``change vnc TARGET`` (removed in 6.0)
    524 ''''''''''''''''''''''''''''''''''''''
    525 
    526 No replacement.  The ``change vnc password`` and ``change DEVICE MEDIUM``
    527 commands are not affected.
    528 
    529 ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0)
    530 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    531 
    532 The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and
    533 ``acl_remove`` commands were removed with no replacement. Authorization
    534 for VNC should be performed using the pluggable QAuthZ objects.
    535 
    536 ``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0)
    537 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    538 
    539 Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead.
    540 
    541 ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
    542 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    543 
    544 Use ``migrate-set-parameters`` instead.
    545 
    546 ``info cpustats`` (removed in 6.1)
    547 ''''''''''''''''''''''''''''''''''
    548 
    549 This command didn't produce any output already. Removed with no replacement.
    550 
    551 Guest Emulator ISAs
    552 -------------------
    553 
    554 RISC-V ISA privilege specification version 1.09.1 (removed in 5.1)
    555 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    556 
    557 The RISC-V ISA privilege specification version 1.09.1 has been removed.
    558 QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
    559 should be used instead of the 1.09.1 version.
    560 
    561 System emulator CPUS
    562 --------------------
    563 
    564 KVM guest support on 32-bit Arm hosts (removed in 5.2)
    565 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
    566 
    567 The Linux kernel has dropped support for allowing 32-bit Arm systems
    568 to host KVM guests as of the 5.7 kernel. Accordingly, QEMU is deprecating
    569 its support for this configuration and will remove it in a future version.
    570 Running 32-bit guests on a 64-bit Arm host remains supported.
    571 
    572 RISC-V ISA Specific CPUs (removed in 5.1)
    573 '''''''''''''''''''''''''''''''''''''''''
    574 
    575 The RISC-V cpus with the ISA version in the CPU name have been removed. The
    576 four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
    577 ``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
    578 option when using the ``rv32`` or ``rv64`` CPUs.
    579 
    580 RISC-V no MMU CPUs (removed in 5.1)
    581 '''''''''''''''''''''''''''''''''''
    582 
    583 The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and
    584 ``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified
    585 via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
    586 
    587 ``compat`` property of server class POWER CPUs (removed in 6.0)
    588 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    589 
    590 The ``max-cpu-compat`` property of the ``pseries`` machine type should be used
    591 instead.
    592 
    593 ``moxie`` CPU (removed in 6.1)
    594 ''''''''''''''''''''''''''''''
    595 
    596 Nobody was using this CPU emulation in QEMU, and there were no test images
    597 available to make sure that the code is still working, so it has been removed
    598 without replacement.
    599 
    600 ``lm32`` CPUs (removed in 6.1)
    601 ''''''''''''''''''''''''''''''
    602 
    603 The only public user of this architecture was the milkymist project,
    604 which has been dead for years; there was never an upstream Linux
    605 port.  Removed without replacement.
    606 
    607 ``unicore32`` CPUs (removed in 6.1)
    608 '''''''''''''''''''''''''''''''''''
    609 
    610 Support for this CPU was removed from the upstream Linux kernel, and
    611 there is no available upstream toolchain to build binaries for it.
    612 Removed without replacement.
    613 
    614 x86 ``Icelake-Client`` CPU (removed in 7.1)
    615 '''''''''''''''''''''''''''''''''''''''''''
    616 
    617 There isn't ever Icelake Client CPU, it is some wrong and imaginary one.
    618 Use ``Icelake-Server`` instead.
    619 
    620 System emulator machines
    621 ------------------------
    622 
    623 ``s390-virtio`` (removed in 2.6)
    624 ''''''''''''''''''''''''''''''''
    625 
    626 Use the ``s390-ccw-virtio`` machine instead.
    627 
    628 The m68k ``dummy`` machine (removed in 2.9)
    629 '''''''''''''''''''''''''''''''''''''''''''
    630 
    631 Use the ``none`` machine with the ``loader`` device instead.
    632 
    633 ``xlnx-ep108`` (removed in 3.0)
    634 '''''''''''''''''''''''''''''''
    635 
    636 The EP108 was an early access development board that is no longer used.
    637 Use the ``xlnx-zcu102`` machine instead.
    638 
    639 ``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1)
    640 '''''''''''''''''''''''''''''''''''''''''''''''''''''
    641 
    642 The version specific Spike machines have been removed in favour of the
    643 generic ``spike`` machine. If you need to specify an older version of the RISC-V
    644 spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument.
    645 
    646 mips ``r4k`` platform (removed in 5.2)
    647 ''''''''''''''''''''''''''''''''''''''
    648 
    649 This machine type was very old and unmaintained. Users should use the ``malta``
    650 machine type instead.
    651 
    652 mips ``fulong2e`` machine alias (removed in 6.0)
    653 ''''''''''''''''''''''''''''''''''''''''''''''''
    654 
    655 This machine has been renamed ``fuloong2e``.
    656 
    657 ``pc-0.10`` up to ``pc-1.3`` (removed in 4.0 up to 6.0)
    658 '''''''''''''''''''''''''''''''''''''''''''''''''''''''
    659 
    660 These machine types were very old and likely could not be used for live
    661 migration from old QEMU versions anymore. Use a newer machine type instead.
    662 
    663 Raspberry Pi ``raspi2`` and ``raspi3`` machines (removed in 6.2)
    664 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    665 
    666 The Raspberry Pi machines come in various models (A, A+, B, B+). To be able
    667 to distinguish which model QEMU is implementing, the ``raspi2`` and ``raspi3``
    668 machines have been renamed ``raspi2b`` and ``raspi3b``.
    669 
    670 Aspeed ``swift-bmc`` machine (removed in 7.0)
    671 '''''''''''''''''''''''''''''''''''''''''''''
    672 
    673 This machine was removed because it was unused. Alternative AST2500 based
    674 OpenPOWER machines are ``witherspoon-bmc`` and ``romulus-bmc``.
    675 
    676 ppc ``taihu`` machine (removed in 7.2)
    677 '''''''''''''''''''''''''''''''''''''''''''''
    678 
    679 This machine was removed because it was partially emulated and 405
    680 machines are very similar. Use the ``ref405ep`` machine instead.
    681 
    682 linux-user mode CPUs
    683 --------------------
    684 
    685 ``tilegx`` CPUs (removed in 6.0)
    686 ''''''''''''''''''''''''''''''''
    687 
    688 The ``tilegx`` guest CPU support has been removed without replacement. It was
    689 only implemented in linux-user mode, but support for this CPU was removed from
    690 the upstream Linux kernel in 2018, and it has also been dropped from glibc, so
    691 there is no new Linux development taking place with this architecture. For
    692 running the old binaries, you can use older versions of QEMU.
    693 
    694 ``ppc64abi32`` CPUs (removed in 7.0)
    695 ''''''''''''''''''''''''''''''''''''
    696 
    697 The ``ppc64abi32`` architecture has a number of issues which regularly
    698 tripped up the CI testing and was suspected to be quite broken. For that
    699 reason the maintainers strongly suspected no one actually used it.
    700 
    701 
    702 TCG introspection features
    703 --------------------------
    704 
    705 TCG trace-events (since 6.2)
    706 ''''''''''''''''''''''''''''
    707 
    708 The ability to add new TCG trace points had bit rotted and as the
    709 feature can be replicated with TCG plugins it was removed. If
    710 any user is currently using this feature and needs help with
    711 converting to using TCG plugins they should contact the qemu-devel
    712 mailing list.
    713 
    714 
    715 System emulator devices
    716 -----------------------
    717 
    718 ``spapr-pci-vfio-host-bridge`` (removed in 2.12)
    719 '''''''''''''''''''''''''''''''''''''''''''''''''
    720 
    721 The ``spapr-pci-vfio-host-bridge`` device type has been replaced by the
    722 ``spapr-pci-host-bridge`` device type.
    723 
    724 ``ivshmem`` (removed in 4.0)
    725 ''''''''''''''''''''''''''''
    726 
    727 Replaced by either the ``ivshmem-plain`` or ``ivshmem-doorbell``.
    728 
    729 ``ide-drive`` (removed in 6.0)
    730 ''''''''''''''''''''''''''''''
    731 
    732 The 'ide-drive' device has been removed. Users should use 'ide-hd' or
    733 'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
    734 
    735 ``scsi-disk`` (removed in 6.0)
    736 ''''''''''''''''''''''''''''''
    737 
    738 The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or
    739 'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
    740 
    741 Related binaries
    742 ----------------
    743 
    744 ``qemu-nbd --partition`` (removed in 5.0)
    745 '''''''''''''''''''''''''''''''''''''''''
    746 
    747 The ``qemu-nbd --partition $digit`` code (also spelled ``-P``)
    748 could only handle MBR partitions, and never correctly handled logical
    749 partitions beyond partition 5.  Exporting a partition can still be
    750 done by utilizing the ``--image-opts`` option with a raw blockdev
    751 using the ``offset`` and ``size`` parameters layered on top of
    752 any other existing blockdev. For example, if partition 1 is 100MiB
    753 long starting at 1MiB, the old command::
    754 
    755   qemu-nbd -t -P 1 -f qcow2 file.qcow2
    756 
    757 can be rewritten as::
    758 
    759   qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2
    760 
    761 ``qemu-img convert -n -o`` (removed in 5.1)
    762 '''''''''''''''''''''''''''''''''''''''''''
    763 
    764 All options specified in ``-o`` are image creation options, so
    765 they are now rejected when used with ``-n`` to skip image creation.
    766 
    767 
    768 ``qemu-img create -b bad file $size`` (removed in 5.1)
    769 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
    770 
    771 When creating an image with a backing file that could not be opened,
    772 ``qemu-img create`` used to issue a warning about the failure but
    773 proceed with the image creation if an explicit size was provided.
    774 However, as the ``-u`` option exists for this purpose, it is safer to
    775 enforce that any failure to open the backing image (including if the
    776 backing file is missing or an incorrect format was specified) is an
    777 error when ``-u`` is not used.
    778 
    779 ``qemu-img amend`` to adjust backing file (removed in 6.1)
    780 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    781 
    782 The use of ``qemu-img amend`` to modify the name or format of a qcow2
    783 backing image was never fully documented or tested, and interferes
    784 with other amend operations that need access to the original backing
    785 image (such as deciding whether a v3 zero cluster may be left
    786 unallocated when converting to a v2 image).  Any changes to the
    787 backing chain should be performed with ``qemu-img rebase -u`` either
    788 before or after the remaining changes being performed by amend, as
    789 appropriate.
    790 
    791 ``qemu-img`` backing file without format (removed in 6.1)
    792 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''
    793 
    794 The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img
    795 convert`` to create or modify an image that depends on a backing file
    796 now requires that an explicit backing format be provided.  This is
    797 for safety: if QEMU probes a different format than what you thought,
    798 the data presented to the guest will be corrupt; similarly, presenting
    799 a raw image to a guest allows a potential security exploit if a future
    800 probe sees a non-raw image based on guest writes.
    801 
    802 To avoid creating unsafe backing chains, you must pass ``-o
    803 backing_fmt=`` (or the shorthand ``-F`` during create) to specify the
    804 intended backing format.  You may use ``qemu-img rebase -u`` to
    805 retroactively add a backing format to an existing image.  However, be
    806 aware that there are already potential security risks to blindly using
    807 ``qemu-img info`` to probe the format of an untrusted backing image,
    808 when deciding what format to add into an existing image.
    809 
    810 Block devices
    811 -------------
    812 
    813 VXHS backend (removed in 5.1)
    814 '''''''''''''''''''''''''''''
    815 
    816 The VXHS code did not compile since v2.12.0. It was removed in 5.1.
    817 
    818 ``sheepdog`` driver (removed in 6.0)
    819 ''''''''''''''''''''''''''''''''''''
    820 
    821 The corresponding upstream server project is no longer maintained.
    822 Users are recommended to switch to an alternative distributed block
    823 device driver such as RBD.