docs/about/removed-features.rst

   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  22 This option has been replaced by ``-net user,guestfwd=...``.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  27 ``-net dump[,vlan=n][,file=filename][,len=maxlen]`` has been replaced by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 Hexadecimal sizes with scaling multipliers (since 8.0)
 412 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
 413
 414 Input parameters that take a size value should only use a size suffix
 415 (such as 'k' or 'M') when the base is written in decimal, and not when
 416 the value is hexadecimal.  That is, '0x20M' should be written either as
 417 '32M' or as '0x2000000'.
 418
 419 ``-chardev`` backend aliases ``tty`` and ``parport`` (removed in 8.0)
 420 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 421
 422 ``tty`` and ``parport`` used to be aliases for ``serial`` and ``parallel``
 423 respectively. The actual backend names should be used instead.
 424
 425 QEMU Machine Protocol (QMP) commands
 426 ------------------------------------
 427
 428 ``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2)
 429 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 430
 431 The "autoload" parameter has been ignored since 2.12.0. All bitmaps
 432 are automatically loaded from qcow2 images.
 433
 434 ``cpu-add`` (removed in 5.2)
 435 ''''''''''''''''''''''''''''
 436
 437 Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
 438 documentation of ``query-hotpluggable-cpus`` for additional details.
 439
 440 ``change`` (removed in 6.0)
 441 '''''''''''''''''''''''''''
 442
 443 Use ``blockdev-change-medium`` or ``change-vnc-password`` or
 444 ``display-update`` instead.
 445
 446 ``query-events`` (removed in 6.0)
 447 '''''''''''''''''''''''''''''''''
 448
 449 The ``query-events`` command has been superseded by the more powerful
 450 and accurate ``query-qmp-schema`` command.
 451
 452 ``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0)
 453 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 454
 455 Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead.
 456
 457 ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
 458 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 459
 460 Use ``migrate_set_parameter`` instead.
 461
 462 ``query-cpus`` (removed in 6.0)
 463 '''''''''''''''''''''''''''''''
 464
 465 The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command.
 466
 467 ``query-cpus-fast`` ``arch`` output member (removed in 6.0)
 468 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 469
 470 The ``arch`` output member of the ``query-cpus-fast`` command is
 471 replaced by the ``target`` output member.
 472
 473 chardev client socket with ``wait`` option (removed in 6.0)
 474 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 475
 476 Character devices creating sockets in client mode should not specify
 477 the 'wait' field, which is only applicable to sockets in server mode
 478
 479 ``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0)
 480 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 481
 482 Removed with no replacement.
 483
 484 ``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0)
 485 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 486
 487 Removed with no replacement.
 488
 489 ``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0)
 490 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 491
 492 The ``status`` field of the ``BlockDirtyInfo`` structure, returned by
 493 these commands is removed. Two new boolean fields, ``recording`` and
 494 ``busy`` effectively replace it.
 495
 496 ``query-block`` result field ``dirty-bitmaps`` (removed in 6.0)
 497 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 498
 499 The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
 500 the query-block command is itself now removed. The ``dirty-bitmaps``
 501 field of the ``BlockDeviceInfo`` struct should be used instead, which is the
 502 type of the ``inserted`` field in query-block replies, as well as the
 503 type of array items in query-named-block-nodes.
 504
 505 ``object-add`` option ``props`` (removed in 6.0)
 506 ''''''''''''''''''''''''''''''''''''''''''''''''
 507
 508 Specify the properties for the object as top-level arguments instead.
 509
 510 Human Monitor Protocol (HMP) commands
 511 -------------------------------------
 512
 513 ``usb_add`` and ``usb_remove`` (removed in 2.12)
 514 ''''''''''''''''''''''''''''''''''''''''''''''''
 515
 516 Replaced by ``device_add`` and ``device_del`` (use ``device_add help`` for a
 517 list of available devices).
 518
 519 ``host_net_add`` and ``host_net_remove`` (removed in 2.12)
 520 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 521
 522 Replaced by ``netdev_add`` and ``netdev_del``.
 523
 524 The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0)
 525 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 526
 527 The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and
 528 'hostfwd_remove' HMP commands has been replaced by ``netdev_id``.
 529
 530 ``cpu-add`` (removed in 5.2)
 531 ''''''''''''''''''''''''''''
 532
 533 Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
 534 documentation of ``query-hotpluggable-cpus`` for additional details.
 535
 536 ``change vnc TARGET`` (removed in 6.0)
 537 ''''''''''''''''''''''''''''''''''''''
 538
 539 No replacement.  The ``change vnc password`` and ``change DEVICE MEDIUM``
 540 commands are not affected.
 541
 542 ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0)
 543 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 544
 545 The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and
 546 ``acl_remove`` commands were removed with no replacement. Authorization
 547 for VNC should be performed using the pluggable QAuthZ objects.
 548
 549 ``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0)
 550 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 551
 552 Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead.
 553
 554 ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
 555 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 556
 557 Use ``migrate-set-parameters`` instead.
 558
 559 ``info cpustats`` (removed in 6.1)
 560 ''''''''''''''''''''''''''''''''''
 561
 562 This command didn't produce any output already. Removed with no replacement.
 563
 564 Guest Emulator ISAs
 565 -------------------
 566
 567 RISC-V ISA privilege specification version 1.09.1 (removed in 5.1)
 568 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 569
 570 The RISC-V ISA privilege specification version 1.09.1 has been removed.
 571 QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
 572 should be used instead of the 1.09.1 version.
 573
 574 System emulator CPUS
 575 --------------------
 576
 577 KVM guest support on 32-bit Arm hosts (removed in 5.2)
 578 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
 579
 580 The Linux kernel has dropped support for allowing 32-bit Arm systems
 581 to host KVM guests as of the 5.7 kernel, and was thus removed from QEMU
 582 as well.  Running 32-bit guests on a 64-bit Arm host remains supported.
 583
 584 RISC-V ISA Specific CPUs (removed in 5.1)
 585 '''''''''''''''''''''''''''''''''''''''''
 586
 587 The RISC-V cpus with the ISA version in the CPU name have been removed. The
 588 four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
 589 ``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
 590 option when using the ``rv32`` or ``rv64`` CPUs.
 591
 592 RISC-V no MMU CPUs (removed in 5.1)
 593 '''''''''''''''''''''''''''''''''''
 594
 595 The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and
 596 ``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified
 597 via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
 598
 599 ``compat`` property of server class POWER CPUs (removed in 6.0)
 600 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 601
 602 The ``max-cpu-compat`` property of the ``pseries`` machine type should be used
 603 instead.
 604
 605 ``moxie`` CPU (removed in 6.1)
 606 ''''''''''''''''''''''''''''''
 607
 608 Nobody was using this CPU emulation in QEMU, and there were no test images
 609 available to make sure that the code is still working, so it has been removed
 610 without replacement.
 611
 612 ``lm32`` CPUs (removed in 6.1)
 613 ''''''''''''''''''''''''''''''
 614
 615 The only public user of this architecture was the milkymist project,
 616 which has been dead for years; there was never an upstream Linux
 617 port.  Removed without replacement.
 618
 619 ``unicore32`` CPUs (removed in 6.1)
 620 '''''''''''''''''''''''''''''''''''
 621
 622 Support for this CPU was removed from the upstream Linux kernel, and
 623 there is no available upstream toolchain to build binaries for it.
 624 Removed without replacement.
 625
 626 x86 ``Icelake-Client`` CPU (removed in 7.1)
 627 '''''''''''''''''''''''''''''''''''''''''''
 628
 629 There isn't ever Icelake Client CPU, it is some wrong and imaginary one.
 630 Use ``Icelake-Server`` instead.
 631
 632 System accelerators
 633 -------------------
 634
 635 Userspace local APIC with KVM (x86, removed 8.0)
 636 ''''''''''''''''''''''''''''''''''''''''''''''''
 637
 638 ``-M kernel-irqchip=off`` cannot be used on KVM if the CPU model includes
 639 a local APIC.  The ``split`` setting is supported, as is using ``-M
 640 kernel-irqchip=off`` when the CPU does not have a local APIC.
 641
 642 System emulator machines
 643 ------------------------
 644
 645 ``s390-virtio`` (removed in 2.6)
 646 ''''''''''''''''''''''''''''''''
 647
 648 Use the ``s390-ccw-virtio`` machine instead.
 649
 650 The m68k ``dummy`` machine (removed in 2.9)
 651 '''''''''''''''''''''''''''''''''''''''''''
 652
 653 Use the ``none`` machine with the ``loader`` device instead.
 654
 655 ``xlnx-ep108`` (removed in 3.0)
 656 '''''''''''''''''''''''''''''''
 657
 658 The EP108 was an early access development board that is no longer used.
 659 Use the ``xlnx-zcu102`` machine instead.
 660
 661 ``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1)
 662 '''''''''''''''''''''''''''''''''''''''''''''''''''''
 663
 664 The version specific Spike machines have been removed in favour of the
 665 generic ``spike`` machine. If you need to specify an older version of the RISC-V
 666 spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument.
 667
 668 mips ``r4k`` platform (removed in 5.2)
 669 ''''''''''''''''''''''''''''''''''''''
 670
 671 This machine type was very old and unmaintained. Users should use the ``malta``
 672 machine type instead.
 673
 674 mips ``fulong2e`` machine alias (removed in 6.0)
 675 ''''''''''''''''''''''''''''''''''''''''''''''''
 676
 677 This machine has been renamed ``fuloong2e``.
 678
 679 ``pc-0.10`` up to ``pc-1.3`` (removed in 4.0 up to 6.0)
 680 '''''''''''''''''''''''''''''''''''''''''''''''''''''''
 681
 682 These machine types were very old and likely could not be used for live
 683 migration from old QEMU versions anymore. Use a newer machine type instead.
 684
 685 Raspberry Pi ``raspi2`` and ``raspi3`` machines (removed in 6.2)
 686 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 687
 688 The Raspberry Pi machines come in various models (A, A+, B, B+). To be able
 689 to distinguish which model QEMU is implementing, the ``raspi2`` and ``raspi3``
 690 machines have been renamed ``raspi2b`` and ``raspi3b``.
 691
 692 Aspeed ``swift-bmc`` machine (removed in 7.0)
 693 '''''''''''''''''''''''''''''''''''''''''''''
 694
 695 This machine was removed because it was unused. Alternative AST2500 based
 696 OpenPOWER machines are ``witherspoon-bmc`` and ``romulus-bmc``.
 697
 698 ppc ``taihu`` machine (removed in 7.2)
 699 '''''''''''''''''''''''''''''''''''''''''''''
 700
 701 This machine was removed because it was partially emulated and 405
 702 machines are very similar. Use the ``ref405ep`` machine instead.
 703
 704 linux-user mode CPUs
 705 --------------------
 706
 707 ``tilegx`` CPUs (removed in 6.0)
 708 ''''''''''''''''''''''''''''''''
 709
 710 The ``tilegx`` guest CPU support has been removed without replacement. It was
 711 only implemented in linux-user mode, but support for this CPU was removed from
 712 the upstream Linux kernel in 2018, and it has also been dropped from glibc, so
 713 there is no new Linux development taking place with this architecture. For
 714 running the old binaries, you can use older versions of QEMU.
 715
 716 ``ppc64abi32`` CPUs (removed in 7.0)
 717 ''''''''''''''''''''''''''''''''''''
 718
 719 The ``ppc64abi32`` architecture has a number of issues which regularly
 720 tripped up the CI testing and was suspected to be quite broken. For that
 721 reason the maintainers strongly suspected no one actually used it.
 722
 723
 724 TCG introspection features
 725 --------------------------
 726
 727 TCG trace-events (since 6.2)
 728 ''''''''''''''''''''''''''''
 729
 730 The ability to add new TCG trace points had bit rotted and as the
 731 feature can be replicated with TCG plugins it was removed. If
 732 any user is currently using this feature and needs help with
 733 converting to using TCG plugins they should contact the qemu-devel
 734 mailing list.
 735
 736
 737 System emulator devices
 738 -----------------------
 739
 740 ``spapr-pci-vfio-host-bridge`` (removed in 2.12)
 741 '''''''''''''''''''''''''''''''''''''''''''''''''
 742
 743 The ``spapr-pci-vfio-host-bridge`` device type has been replaced by the
 744 ``spapr-pci-host-bridge`` device type.
 745
 746 ``ivshmem`` (removed in 4.0)
 747 ''''''''''''''''''''''''''''
 748
 749 Replaced by either the ``ivshmem-plain`` or ``ivshmem-doorbell``.
 750
 751 ``ide-drive`` (removed in 6.0)
 752 ''''''''''''''''''''''''''''''
 753
 754 The 'ide-drive' device has been removed. Users should use 'ide-hd' or
 755 'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
 756
 757 ``scsi-disk`` (removed in 6.0)
 758 ''''''''''''''''''''''''''''''
 759
 760 The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or
 761 'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
 762
 763 Related binaries
 764 ----------------
 765
 766 ``qemu-nbd --partition`` (removed in 5.0)
 767 '''''''''''''''''''''''''''''''''''''''''
 768
 769 The ``qemu-nbd --partition $digit`` code (also spelled ``-P``)
 770 could only handle MBR partitions, and never correctly handled logical
 771 partitions beyond partition 5.  Exporting a partition can still be
 772 done by utilizing the ``--image-opts`` option with a raw blockdev
 773 using the ``offset`` and ``size`` parameters layered on top of
 774 any other existing blockdev. For example, if partition 1 is 100MiB
 775 long starting at 1MiB, the old command::
 776
 777   qemu-nbd -t -P 1 -f qcow2 file.qcow2
 778
 779 can be rewritten as::
 780
 781   qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2
 782
 783 ``qemu-img convert -n -o`` (removed in 5.1)
 784 '''''''''''''''''''''''''''''''''''''''''''
 785
 786 All options specified in ``-o`` are image creation options, so
 787 they are now rejected when used with ``-n`` to skip image creation.
 788
 789
 790 ``qemu-img create -b bad file $size`` (removed in 5.1)
 791 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
 792
 793 When creating an image with a backing file that could not be opened,
 794 ``qemu-img create`` used to issue a warning about the failure but
 795 proceed with the image creation if an explicit size was provided.
 796 However, as the ``-u`` option exists for this purpose, it is safer to
 797 enforce that any failure to open the backing image (including if the
 798 backing file is missing or an incorrect format was specified) is an
 799 error when ``-u`` is not used.
 800
 801 ``qemu-img amend`` to adjust backing file (removed in 6.1)
 802 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 803
 804 The use of ``qemu-img amend`` to modify the name or format of a qcow2
 805 backing image was never fully documented or tested, and interferes
 806 with other amend operations that need access to the original backing
 807 image (such as deciding whether a v3 zero cluster may be left
 808 unallocated when converting to a v2 image).  Any changes to the
 809 backing chain should be performed with ``qemu-img rebase -u`` either
 810 before or after the remaining changes being performed by amend, as
 811 appropriate.
 812
 813 ``qemu-img`` backing file without format (removed in 6.1)
 814 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 815
 816 The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img
 817 convert`` to create or modify an image that depends on a backing file
 818 now requires that an explicit backing format be provided.  This is
 819 for safety: if QEMU probes a different format than what you thought,
 820 the data presented to the guest will be corrupt; similarly, presenting
 821 a raw image to a guest allows a potential security exploit if a future
 822 probe sees a non-raw image based on guest writes.
 823
 824 To avoid creating unsafe backing chains, you must pass ``-o
 825 backing_fmt=`` (or the shorthand ``-F`` during create) to specify the
 826 intended backing format.  You may use ``qemu-img rebase -u`` to
 827 retroactively add a backing format to an existing image.  However, be
 828 aware that there are already potential security risks to blindly using
 829 ``qemu-img info`` to probe the format of an untrusted backing image,
 830 when deciding what format to add into an existing image.
 831
 832 Block devices
 833 -------------
 834
 835 VXHS backend (removed in 5.1)
 836 '''''''''''''''''''''''''''''
 837
 838 The VXHS code did not compile since v2.12.0. It was removed in 5.1.
 839
 840 ``sheepdog`` driver (removed in 6.0)
 841 ''''''''''''''''''''''''''''''''''''
 842
 843 The corresponding upstream server project is no longer maintained.
 844 Users are recommended to switch to an alternative distributed block
 845 device driver such as RBD.