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  22 This option has been replaced by ``-net user,guestfwd=...``.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  27 ``-net dump[,vlan=n][,file=filename][,len=maxlen]`` has been replaced by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 QEMU Machine Protocol (QMP) commands
 334 ------------------------------------
 335
 336 ``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2)
 337 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 338
 339 The "autoload" parameter has been ignored since 2.12.0. All bitmaps
 340 are automatically loaded from qcow2 images.
 341
 342 ``cpu-add`` (removed in 5.2)
 343 ''''''''''''''''''''''''''''
 344
 345 Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
 346 documentation of ``query-hotpluggable-cpus`` for additional details.
 347
 348 ``change`` (removed in 6.0)
 349 '''''''''''''''''''''''''''
 350
 351 Use ``blockdev-change-medium`` or ``change-vnc-password`` instead.
 352
 353 ``query-events`` (removed in 6.0)
 354 '''''''''''''''''''''''''''''''''
 355
 356 The ``query-events`` command has been superseded by the more powerful
 357 and accurate ``query-qmp-schema`` command.
 358
 359 ``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0)
 360 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 361
 362 Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead.
 363
 364 ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
 365 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 366
 367 Use ``migrate_set_parameter`` instead.
 368
 369 ``query-cpus`` (removed in 6.0)
 370 '''''''''''''''''''''''''''''''
 371
 372 The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command.
 373
 374 ``query-cpus-fast`` ``arch`` output member (removed in 6.0)
 375 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 376
 377 The ``arch`` output member of the ``query-cpus-fast`` command is
 378 replaced by the ``target`` output member.
 379
 380 chardev client socket with ``wait`` option (removed in 6.0)
 381 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 382
 383 Character devices creating sockets in client mode should not specify
 384 the 'wait' field, which is only applicable to sockets in server mode
 385
 386 ``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0)
 387 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 388
 389 Removed with no replacement.
 390
 391 ``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0)
 392 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 393
 394 Removed with no replacement.
 395
 396 ``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0)
 397 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 398
 399 The ``status`` field of the ``BlockDirtyInfo`` structure, returned by
 400 these commands is removed. Two new boolean fields, ``recording`` and
 401 ``busy`` effectively replace it.
 402
 403 ``query-block`` result field ``dirty-bitmaps`` (removed in 6.0)
 404 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 405
 406 The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
 407 the query-block command is itself now removed. The ``dirty-bitmaps``
 408 field of the ``BlockDeviceInfo`` struct should be used instead, which is the
 409 type of the ``inserted`` field in query-block replies, as well as the
 410 type of array items in query-named-block-nodes.
 411
 412 ``object-add`` option ``props`` (removed in 6.0)
 413 ''''''''''''''''''''''''''''''''''''''''''''''''
 414
 415 Specify the properties for the object as top-level arguments instead.
 416
 417 Human Monitor Protocol (HMP) commands
 418 -------------------------------------
 419
 420 ``usb_add`` and ``usb_remove`` (removed in 2.12)
 421 ''''''''''''''''''''''''''''''''''''''''''''''''
 422
 423 Replaced by ``device_add`` and ``device_del`` (use ``device_add help`` for a
 424 list of available devices).
 425
 426 ``host_net_add`` and ``host_net_remove`` (removed in 2.12)
 427 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 428
 429 Replaced by ``netdev_add`` and ``netdev_del``.
 430
 431 The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0)
 432 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 433
 434 The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and
 435 'hostfwd_remove' HMP commands has been replaced by ``netdev_id``.
 436
 437 ``cpu-add`` (removed in 5.2)
 438 ''''''''''''''''''''''''''''
 439
 440 Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
 441 documentation of ``query-hotpluggable-cpus`` for additional details.
 442
 443 ``change vnc TARGET`` (removed in 6.0)
 444 ''''''''''''''''''''''''''''''''''''''
 445
 446 No replacement.  The ``change vnc password`` and ``change DEVICE MEDIUM``
 447 commands are not affected.
 448
 449 ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0)
 450 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 451
 452 The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and
 453 ``acl_remove`` commands were removed with no replacement. Authorization
 454 for VNC should be performed using the pluggable QAuthZ objects.
 455
 456 ``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0)
 457 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 458
 459 Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead.
 460
 461 ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
 462 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 463
 464 Use ``migrate-set-parameters`` instead.
 465
 466 ``info cpustats`` (removed in 6.1)
 467 ''''''''''''''''''''''''''''''''''
 468
 469 This command didn't produce any output already. Removed with no replacement.
 470
 471 Guest Emulator ISAs
 472 -------------------
 473
 474 RISC-V ISA privilege specification version 1.09.1 (removed in 5.1)
 475 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 476
 477 The RISC-V ISA privilege specification version 1.09.1 has been removed.
 478 QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
 479 should be used instead of the 1.09.1 version.
 480
 481 System emulator CPUS
 482 --------------------
 483
 484 KVM guest support on 32-bit Arm hosts (removed in 5.2)
 485 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
 486
 487 The Linux kernel has dropped support for allowing 32-bit Arm systems
 488 to host KVM guests as of the 5.7 kernel. Accordingly, QEMU is deprecating
 489 its support for this configuration and will remove it in a future version.
 490 Running 32-bit guests on a 64-bit Arm host remains supported.
 491
 492 RISC-V ISA Specific CPUs (removed in 5.1)
 493 '''''''''''''''''''''''''''''''''''''''''
 494
 495 The RISC-V cpus with the ISA version in the CPU name have been removed. The
 496 four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
 497 ``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
 498 option when using the ``rv32`` or ``rv64`` CPUs.
 499
 500 RISC-V no MMU CPUs (removed in 5.1)
 501 '''''''''''''''''''''''''''''''''''
 502
 503 The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and
 504 ``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified
 505 via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
 506
 507 ``compat`` property of server class POWER CPUs (removed in 6.0)
 508 '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 509
 510 The ``max-cpu-compat`` property of the ``pseries`` machine type should be used
 511 instead.
 512
 513 ``moxie`` CPU (removed in 6.1)
 514 ''''''''''''''''''''''''''''''
 515
 516 Nobody was using this CPU emulation in QEMU, and there were no test images
 517 available to make sure that the code is still working, so it has been removed
 518 without replacement.
 519
 520 ``lm32`` CPUs (removed in 6.1)
 521 ''''''''''''''''''''''''''''''
 522
 523 The only public user of this architecture was the milkymist project,
 524 which has been dead for years; there was never an upstream Linux
 525 port.  Removed without replacement.
 526
 527 ``unicore32`` CPUs (removed in 6.1)
 528 '''''''''''''''''''''''''''''''''''
 529
 530 Support for this CPU was removed from the upstream Linux kernel, and
 531 there is no available upstream toolchain to build binaries for it.
 532 Removed without replacement.
 533
 534 System emulator machines
 535 ------------------------
 536
 537 ``s390-virtio`` (removed in 2.6)
 538 ''''''''''''''''''''''''''''''''
 539
 540 Use the ``s390-ccw-virtio`` machine instead.
 541
 542 The m68k ``dummy`` machine (removed in 2.9)
 543 '''''''''''''''''''''''''''''''''''''''''''
 544
 545 Use the ``none`` machine with the ``loader`` device instead.
 546
 547 ``xlnx-ep108`` (removed in 3.0)
 548 '''''''''''''''''''''''''''''''
 549
 550 The EP108 was an early access development board that is no longer used.
 551 Use the ``xlnx-zcu102`` machine instead.
 552
 553 ``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1)
 554 '''''''''''''''''''''''''''''''''''''''''''''''''''''
 555
 556 The version specific Spike machines have been removed in favour of the
 557 generic ``spike`` machine. If you need to specify an older version of the RISC-V
 558 spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument.
 559
 560 mips ``r4k`` platform (removed in 5.2)
 561 ''''''''''''''''''''''''''''''''''''''
 562
 563 This machine type was very old and unmaintained. Users should use the ``malta``
 564 machine type instead.
 565
 566 mips ``fulong2e`` machine alias (removed in 6.0)
 567 ''''''''''''''''''''''''''''''''''''''''''''''''
 568
 569 This machine has been renamed ``fuloong2e``.
 570
 571 ``pc-0.10`` up to ``pc-1.3`` (removed in 4.0 up to 6.0)
 572 '''''''''''''''''''''''''''''''''''''''''''''''''''''''
 573
 574 These machine types were very old and likely could not be used for live
 575 migration from old QEMU versions anymore. Use a newer machine type instead.
 576
 577 Raspberry Pi ``raspi2`` and ``raspi3`` machines (removed in 6.2)
 578 ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
 579
 580 The Raspberry Pi machines come in various models (A, A+, B, B+). To be able
 581 to distinguish which model QEMU is implementing, the ``raspi2`` and ``raspi3``
 582 machines have been renamed ``raspi2b`` and ``raspi3b``.
 583
 584
 585 linux-user mode CPUs
 586 --------------------
 587
 588 ``tilegx`` CPUs (removed in 6.0)
 589 ''''''''''''''''''''''''''''''''
 590
 591 The ``tilegx`` guest CPU support has been removed without replacement. It was
 592 only implemented in linux-user mode, but support for this CPU was removed from
 593 the upstream Linux kernel in 2018, and it has also been dropped from glibc, so
 594 there is no new Linux development taking place with this architecture. For
 595 running the old binaries, you can use older versions of QEMU.
 596
 597 System emulator devices
 598 -----------------------
 599
 600 ``spapr-pci-vfio-host-bridge`` (removed in 2.12)
 601 '''''''''''''''''''''''''''''''''''''''''''''''''
 602
 603 The ``spapr-pci-vfio-host-bridge`` device type has been replaced by the
 604 ``spapr-pci-host-bridge`` device type.
 605
 606 ``ivshmem`` (removed in 4.0)
 607 ''''''''''''''''''''''''''''
 608
 609 Replaced by either the ``ivshmem-plain`` or ``ivshmem-doorbell``.
 610
 611 ``ide-drive`` (removed in 6.0)
 612 ''''''''''''''''''''''''''''''
 613
 614 The 'ide-drive' device has been removed. Users should use 'ide-hd' or
 615 'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
 616
 617 ``scsi-disk`` (removed in 6.0)
 618 ''''''''''''''''''''''''''''''
 619
 620 The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or
 621 'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
 622
 623 Related binaries
 624 ----------------
 625
 626 ``qemu-nbd --partition`` (removed in 5.0)
 627 '''''''''''''''''''''''''''''''''''''''''
 628
 629 The ``qemu-nbd --partition $digit`` code (also spelled ``-P``)
 630 could only handle MBR partitions, and never correctly handled logical
 631 partitions beyond partition 5.  Exporting a partition can still be
 632 done by utilizing the ``--image-opts`` option with a raw blockdev
 633 using the ``offset`` and ``size`` parameters layered on top of
 634 any other existing blockdev. For example, if partition 1 is 100MiB
 635 long starting at 1MiB, the old command::
 636
 637   qemu-nbd -t -P 1 -f qcow2 file.qcow2
 638
 639 can be rewritten as::
 640
 641   qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2
 642
 643 ``qemu-img convert -n -o`` (removed in 5.1)
 644 '''''''''''''''''''''''''''''''''''''''''''
 645
 646 All options specified in ``-o`` are image creation options, so
 647 they are now rejected when used with ``-n`` to skip image creation.
 648
 649
 650 ``qemu-img create -b bad file $size`` (removed in 5.1)
 651 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
 652
 653 When creating an image with a backing file that could not be opened,
 654 ``qemu-img create`` used to issue a warning about the failure but
 655 proceed with the image creation if an explicit size was provided.
 656 However, as the ``-u`` option exists for this purpose, it is safer to
 657 enforce that any failure to open the backing image (including if the
 658 backing file is missing or an incorrect format was specified) is an
 659 error when ``-u`` is not used.
 660
 661 qemu-img amend to adjust backing file (removed in 6.1)
 662 ''''''''''''''''''''''''''''''''''''''''''''''''''''''
 663
 664 The use of ``qemu-img amend`` to modify the name or format of a qcow2
 665 backing image was never fully documented or tested, and interferes
 666 with other amend operations that need access to the original backing
 667 image (such as deciding whether a v3 zero cluster may be left
 668 unallocated when converting to a v2 image).  Any changes to the
 669 backing chain should be performed with ``qemu-img rebase -u`` either
 670 before or after the remaining changes being performed by amend, as
 671 appropriate.
 672
 673 qemu-img backing file without format (removed in 6.1)
 674 '''''''''''''''''''''''''''''''''''''''''''''''''''''
 675
 676 The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img
 677 convert`` to create or modify an image that depends on a backing file
 678 now requires that an explicit backing format be provided.  This is
 679 for safety: if QEMU probes a different format than what you thought,
 680 the data presented to the guest will be corrupt; similarly, presenting
 681 a raw image to a guest allows a potential security exploit if a future
 682 probe sees a non-raw image based on guest writes.
 683
 684 To avoid creating unsafe backing chains, you must pass ``-o
 685 backing_fmt=`` (or the shorthand ``-F`` during create) to specify the
 686 intended backing format.  You may use ``qemu-img rebase -u`` to
 687 retroactively add a backing format to an existing image.  However, be
 688 aware that there are already potential security risks to blindly using
 689 ``qemu-img info`` to probe the format of an untrusted backing image,
 690 when deciding what format to add into an existing image.
 691
 692 Block devices
 693 -------------
 694
 695 VXHS backend (removed in 5.1)
 696 '''''''''''''''''''''''''''''
 697
 698 The VXHS code did not compile since v2.12.0. It was removed in 5.1.
 699
 700 ``sheepdog`` driver (removed in 6.0)
 701 ''''''''''''''''''''''''''''''''''''
 702
 703 The corresponding upstream server project is no longer maintained.
 704 Users are recommended to switch to an alternative distributed block
 705 device driver such as RBD.