xref: /openbmc/qemu/docs/about/removed-features.rst (revision f81c60c24497e912d2fcf9d250c6f3de01db68b9)
1
2Removed features
3================
4
5What follows is a record of recently removed, formerly deprecated
6features that serves as a record for users who have encountered
7trouble after a recent upgrade.
8
9System emulator command line arguments
10--------------------------------------
11
12``-hdachs`` (removed in 2.12)
13'''''''''''''''''''''''''''''
14
15The 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
22This option has been replaced by ``-net user,guestfwd=...``.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27``-net dump[,vlan=n][,file=filename][,len=maxlen]`` has been replaced by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]``.
29Note 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
34This was just a dummy option that has been ignored, since the in-kernel PIT
35cannot 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
42There is no replacement, the ``-tdf`` option has just been ignored since the
43behaviour that could be changed by this option in qemu-kvm is now the default
44when 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
50The 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
57Use ``-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
63The term "vlan" was very confusing for most users in this context (it's about
64specifying a hub ID, not about IEEE 802.1Q or something similar), so this
65has been removed. To connect one NIC frontend with a network backend, either
66use ``-nic ...`` (e.g. for on-board NICs) or use ``-netdev ...,id=n`` together
67with ``-device ...,netdev=n`` (for full control over pluggable NICs). To
68connect multiple NICs or network backends via a hub device (which is what
69vlan 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
75Use ``-machine kernel_irqchip=off`` instead.
76
77``-no-kvm-pit-reinjection`` (removed in 3.0)
78''''''''''''''''''''''''''''''''''''''''''''
79
80Use ``-global kvm-pit.lost_tick_policy=discard`` instead.
81
82``-balloon`` (removed in 3.1)
83'''''''''''''''''''''''''''''
84
85The ``-balloon virtio`` option has been replaced by ``-device virtio-balloon``.
86The ``-balloon none`` option was a no-op and has no replacement.
87
88``-bootp`` (removed in 3.1)
89'''''''''''''''''''''''''''
90
91The ``-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).
94The new syntax allows different settings to be provided per NIC.
95
96``-redir`` (removed in 3.1)
97'''''''''''''''''''''''''''
98
99The ``-redir [tcp|udp]:hostport:[guestaddr]:guestport`` option is replaced
100by either ``-netdev
101user,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
105per NIC.
106
107``-smb`` (removed in 3.1)
108'''''''''''''''''''''''''
109
110The ``-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).
113The new syntax allows different settings to be provided per NIC.
114
115``-tftp`` (removed in 3.1)
116''''''''''''''''''''''''''
117
118The ``-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).
121The new syntax allows different settings to be provided per NIC.
122
123``-localtime`` (removed in 3.1)
124'''''''''''''''''''''''''''''''
125
126Replaced by ``-rtc base=localtime``.
127
128``-nodefconfig`` (removed in 3.1)
129'''''''''''''''''''''''''''''''''
130
131Use ``-no-user-config`` instead.
132
133``-rtc-td-hack`` (removed in 3.1)
134'''''''''''''''''''''''''''''''''
135
136Use ``-rtc driftfix=slew`` instead.
137
138``-startdate`` (removed in 3.1)
139'''''''''''''''''''''''''''''''
140
141Replaced by ``-rtc base=date``.
142
143``-vnc ...,tls=...``, ``-vnc ...,x509=...`` & ``-vnc ...,x509verify=...`` (removed in 3.1)
144''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
145
146The "tls-creds" option should be used instead to point to a "tls-creds-x509"
147object created using "-object".
148
149``-mem-path`` fallback to RAM (removed in 5.0)
150''''''''''''''''''''''''''''''''''''''''''''''
151
152If guest RAM allocation from file pointed by ``mem-path`` failed,
153QEMU was falling back to allocating from RAM, which might have resulted
154in unpredictable behavior since the backing file specified by the user
155as ignored. Currently, users are responsible for making sure the backing storage
156specified 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
162The ``name`` parameter of the ``-net`` option was a synonym
163for the ``id`` parameter, which should now be used instead.
164
165``-numa node,mem=...`` (removed in 5.1)
166'''''''''''''''''''''''''''''''''''''''
167
168The parameter ``mem`` of ``-numa node`` was used to assign a part of guest RAM
169to a NUMA node. But when using it, it's impossible to manage a specified RAM
170chunk on the host side (like bind it to a host node, setting bind policy, ...),
171so the guest ends up with the fake NUMA configuration with suboptiomal
172performance.
173However since 2014 there is an alternative way to assign RAM to a NUMA node
174using parameter ``memdev``, which does the same as ``mem`` and adds
175means to actually manage node RAM on the host side. Use parameter ``memdev``
176with *memory-backend-ram* backend as replacement for parameter ``mem``
177to achieve the same fake NUMA effect or a properly configured
178*memory-backend-file* backend to actually benefit from NUMA configuration.
179New machine versions (since 5.1) will not accept the option but it will still
180work with old machine types. User can check the QAPI schema to see if the legacy
181option is supported by looking at MachineInfo::numa-mem-supported property.
182
183``-numa`` node (without memory specified) (removed in 5.2)
184''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
185
186Splitting RAM by default between NUMA nodes had the same issues as ``mem``
187parameter with the difference that the role of the user plays QEMU using
188implicit generic or board specific splitting rule.
189Use ``memdev`` with *memory-backend-ram* backend or ``mem`` (if
190it's supported by used machine type) to define mapping explicitly instead.
191Users of existing VMs, wishing to preserve the same RAM distribution, should
192configure it explicitly using ``-numa node,memdev`` options. Current RAM
193distribution can be retrieved using HMP command ``info numa`` and if separate
194memory devices (pc|nv-dimm) are present use ``info memory-device`` and subtract
195device memory from output of ``info numa``.
196
197``-smp`` (invalid topologies) (removed in 5.2)
198''''''''''''''''''''''''''''''''''''''''''''''
199
200CPU topology properties should describe whole machine topology including
201possible CPUs.
202
203However, historically it was possible to start QEMU with an incorrect topology
204where *n* <= *sockets* * *cores* * *threads* < *maxcpus*,
205which could lead to an incorrect topology enumeration by the guest.
206Support for invalid topologies is removed, the user must ensure
207topologies 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
213The ``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
219The ``-no-kvm`` argument was a synonym for setting ``-machine accel=tcg``.
220
221``-realtime`` (removed in 6.0)
222''''''''''''''''''''''''''''''
223
224The ``-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
230Use ``-display sdl,show-cursor=on``, ``-display gtk,show-cursor=on``
231or ``-display default,show-cursor=on`` instead.
232
233``-tb-size`` option (removed in 6.0)
234''''''''''''''''''''''''''''''''''''
235
236QEMU 5.0 introduced an alternative syntax to specify the size of the translation
237block cache, ``-accel tcg,tb-size=``.
238
239``-usbdevice audio`` (removed in 6.0)
240'''''''''''''''''''''''''''''''''''''
241
242This option lacked the possibility to specify an audio backend device.
243Use ``-device usb-audio`` now instead (and specify a corresponding USB
244host controller or ``-usb`` if necessary).
245
246``-vnc acl`` (removed in 6.0)
247'''''''''''''''''''''''''''''
248
249The ``acl`` option to the ``-vnc`` argument has been replaced
250by the ``tls-authz`` and ``sasl-authz`` options.
251
252``-mon ...,control=readline,pretty=on|off`` (removed in 6.0)
253''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
254
255The ``pretty=on|off`` switch has no effect for HMP monitors and
256its use is rejected.
257
258``-drive file=json:{...{'driver':'file'}}`` (removed in 6.0)
259''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
260
261The 'file' driver for drives is no longer appropriate for character or host
262devices and will only accept regular files (S_IFREG). The correct driver
263for these file types is 'host_cdrom' or 'host_device' as appropriate.
264
265Floppy controllers' drive properties (removed in 6.0)
266'''''''''''''''''''''''''''''''''''''''''''''''''''''
267
268Use ``-device floppy,...`` instead.  When configuring onboard floppy
269controllers
270::
271
272    -global isa-fdc.driveA=...
273    -global sysbus-fdc.driveA=...
274    -global SUNW,fdtwo.drive=...
275
276become
277::
278
279    -device floppy,unit=0,drive=...
280
281and
282::
283
284    -global isa-fdc.driveB=...
285    -global sysbus-fdc.driveB=...
286
287become
288::
289
290    -device floppy,unit=1,drive=...
291
292When plugging in a floppy controller
293::
294
295    -device isa-fdc,...,driveA=...
296
297becomes
298::
299
300    -device isa-fdc,...
301    -device floppy,unit=0,drive=...
302
303and
304::
305
306    -device isa-fdc,...,driveB=...
307
308becomes
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
317Drives with interface types other than ``if=none`` are for onboard
318devices.  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
324This option was undocumented and not used in the field.
325Use ``-device usb-ccid`` instead.
326
327RISC-V firmware not booted by default (removed in 5.1)
328''''''''''''''''''''''''''''''''''''''''''''''''''''''
329
330QEMU 5.1 changes the default behaviour from ``-bios none`` to ``-bios default``
331for the RISC-V ``virt`` machine and ``sifive_u`` machine.
332
333``-no-quit`` (removed in 7.0)
334'''''''''''''''''''''''''''''
335
336The ``-no-quit`` was a synonym for ``-display ...,window-close=off`` which
337should be used instead.
338
339``--enable-fips`` (removed in 7.1)
340''''''''''''''''''''''''''''''''''
341
342This option restricted usage of certain cryptographic algorithms when
343the host is operating in FIPS mode.
344
345If FIPS compliance is required, QEMU should be built with the ``libgcrypt``
346or ``gnutls`` library enabled as a cryptography provider.
347
348Neither the ``nettle`` library, or the built-in cryptography provider are
349supported on FIPS enabled hosts.
350
351QEMU Machine Protocol (QMP) commands
352------------------------------------
353
354``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2)
355''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
356
357The "autoload" parameter has been ignored since 2.12.0. All bitmaps
358are automatically loaded from qcow2 images.
359
360``cpu-add`` (removed in 5.2)
361''''''''''''''''''''''''''''
362
363Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
364documentation of ``query-hotpluggable-cpus`` for additional details.
365
366``change`` (removed in 6.0)
367'''''''''''''''''''''''''''
368
369Use ``blockdev-change-medium`` or ``change-vnc-password`` or
370``display-update`` instead.
371
372``query-events`` (removed in 6.0)
373'''''''''''''''''''''''''''''''''
374
375The ``query-events`` command has been superseded by the more powerful
376and accurate ``query-qmp-schema`` command.
377
378``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0)
379''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
380
381Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead.
382
383``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
384'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
385
386Use ``migrate_set_parameter`` instead.
387
388``query-cpus`` (removed in 6.0)
389'''''''''''''''''''''''''''''''
390
391The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command.
392
393``query-cpus-fast`` ``arch`` output member (removed in 6.0)
394'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
395
396The ``arch`` output member of the ``query-cpus-fast`` command is
397replaced by the ``target`` output member.
398
399chardev client socket with ``wait`` option (removed in 6.0)
400'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
401
402Character devices creating sockets in client mode should not specify
403the 'wait' field, which is only applicable to sockets in server mode
404
405``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0)
406''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
407
408Removed with no replacement.
409
410``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0)
411'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
412
413Removed with no replacement.
414
415``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0)
416'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
417
418The ``status`` field of the ``BlockDirtyInfo`` structure, returned by
419these commands is removed. Two new boolean fields, ``recording`` and
420``busy`` effectively replace it.
421
422``query-block`` result field ``dirty-bitmaps`` (removed in 6.0)
423'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
424
425The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
426the query-block command is itself now removed. The ``dirty-bitmaps``
427field of the ``BlockDeviceInfo`` struct should be used instead, which is the
428type of the ``inserted`` field in query-block replies, as well as the
429type of array items in query-named-block-nodes.
430
431``object-add`` option ``props`` (removed in 6.0)
432''''''''''''''''''''''''''''''''''''''''''''''''
433
434Specify the properties for the object as top-level arguments instead.
435
436Human Monitor Protocol (HMP) commands
437-------------------------------------
438
439``usb_add`` and ``usb_remove`` (removed in 2.12)
440''''''''''''''''''''''''''''''''''''''''''''''''
441
442Replaced by ``device_add`` and ``device_del`` (use ``device_add help`` for a
443list of available devices).
444
445``host_net_add`` and ``host_net_remove`` (removed in 2.12)
446''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
447
448Replaced by ``netdev_add`` and ``netdev_del``.
449
450The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0)
451'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
452
453The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and
454'hostfwd_remove' HMP commands has been replaced by ``netdev_id``.
455
456``cpu-add`` (removed in 5.2)
457''''''''''''''''''''''''''''
458
459Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
460documentation of ``query-hotpluggable-cpus`` for additional details.
461
462``change vnc TARGET`` (removed in 6.0)
463''''''''''''''''''''''''''''''''''''''
464
465No replacement.  The ``change vnc password`` and ``change DEVICE MEDIUM``
466commands are not affected.
467
468``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0)
469'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
470
471The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and
472``acl_remove`` commands were removed with no replacement. Authorization
473for VNC should be performed using the pluggable QAuthZ objects.
474
475``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0)
476'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
477
478Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead.
479
480``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
481'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
482
483Use ``migrate-set-parameters`` instead.
484
485``info cpustats`` (removed in 6.1)
486''''''''''''''''''''''''''''''''''
487
488This command didn't produce any output already. Removed with no replacement.
489
490Guest Emulator ISAs
491-------------------
492
493RISC-V ISA privilege specification version 1.09.1 (removed in 5.1)
494''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
495
496The RISC-V ISA privilege specification version 1.09.1 has been removed.
497QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
498should be used instead of the 1.09.1 version.
499
500System emulator CPUS
501--------------------
502
503KVM guest support on 32-bit Arm hosts (removed in 5.2)
504''''''''''''''''''''''''''''''''''''''''''''''''''''''
505
506The Linux kernel has dropped support for allowing 32-bit Arm systems
507to host KVM guests as of the 5.7 kernel. Accordingly, QEMU is deprecating
508its support for this configuration and will remove it in a future version.
509Running 32-bit guests on a 64-bit Arm host remains supported.
510
511RISC-V ISA Specific CPUs (removed in 5.1)
512'''''''''''''''''''''''''''''''''''''''''
513
514The RISC-V cpus with the ISA version in the CPU name have been removed. The
515four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
516``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
517option when using the ``rv32`` or ``rv64`` CPUs.
518
519RISC-V no MMU CPUs (removed in 5.1)
520'''''''''''''''''''''''''''''''''''
521
522The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and
523``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified
524via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
525
526``compat`` property of server class POWER CPUs (removed in 6.0)
527'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
528
529The ``max-cpu-compat`` property of the ``pseries`` machine type should be used
530instead.
531
532``moxie`` CPU (removed in 6.1)
533''''''''''''''''''''''''''''''
534
535Nobody was using this CPU emulation in QEMU, and there were no test images
536available to make sure that the code is still working, so it has been removed
537without replacement.
538
539``lm32`` CPUs (removed in 6.1)
540''''''''''''''''''''''''''''''
541
542The only public user of this architecture was the milkymist project,
543which has been dead for years; there was never an upstream Linux
544port.  Removed without replacement.
545
546``unicore32`` CPUs (removed in 6.1)
547'''''''''''''''''''''''''''''''''''
548
549Support for this CPU was removed from the upstream Linux kernel, and
550there is no available upstream toolchain to build binaries for it.
551Removed without replacement.
552
553System emulator machines
554------------------------
555
556``s390-virtio`` (removed in 2.6)
557''''''''''''''''''''''''''''''''
558
559Use the ``s390-ccw-virtio`` machine instead.
560
561The m68k ``dummy`` machine (removed in 2.9)
562'''''''''''''''''''''''''''''''''''''''''''
563
564Use the ``none`` machine with the ``loader`` device instead.
565
566``xlnx-ep108`` (removed in 3.0)
567'''''''''''''''''''''''''''''''
568
569The EP108 was an early access development board that is no longer used.
570Use the ``xlnx-zcu102`` machine instead.
571
572``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1)
573'''''''''''''''''''''''''''''''''''''''''''''''''''''
574
575The version specific Spike machines have been removed in favour of the
576generic ``spike`` machine. If you need to specify an older version of the RISC-V
577spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument.
578
579mips ``r4k`` platform (removed in 5.2)
580''''''''''''''''''''''''''''''''''''''
581
582This machine type was very old and unmaintained. Users should use the ``malta``
583machine type instead.
584
585mips ``fulong2e`` machine alias (removed in 6.0)
586''''''''''''''''''''''''''''''''''''''''''''''''
587
588This machine has been renamed ``fuloong2e``.
589
590``pc-0.10`` up to ``pc-1.3`` (removed in 4.0 up to 6.0)
591'''''''''''''''''''''''''''''''''''''''''''''''''''''''
592
593These machine types were very old and likely could not be used for live
594migration from old QEMU versions anymore. Use a newer machine type instead.
595
596Raspberry Pi ``raspi2`` and ``raspi3`` machines (removed in 6.2)
597''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
598
599The Raspberry Pi machines come in various models (A, A+, B, B+). To be able
600to distinguish which model QEMU is implementing, the ``raspi2`` and ``raspi3``
601machines have been renamed ``raspi2b`` and ``raspi3b``.
602
603Aspeed ``swift-bmc`` machine (removed in 7.0)
604'''''''''''''''''''''''''''''''''''''''''''''
605
606This machine was removed because it was unused. Alternative AST2500 based
607OpenPOWER machines are ``witherspoon-bmc`` and ``romulus-bmc``.
608
609linux-user mode CPUs
610--------------------
611
612``tilegx`` CPUs (removed in 6.0)
613''''''''''''''''''''''''''''''''
614
615The ``tilegx`` guest CPU support has been removed without replacement. It was
616only implemented in linux-user mode, but support for this CPU was removed from
617the upstream Linux kernel in 2018, and it has also been dropped from glibc, so
618there is no new Linux development taking place with this architecture. For
619running the old binaries, you can use older versions of QEMU.
620
621``ppc64abi32`` CPUs (removed in 7.0)
622''''''''''''''''''''''''''''''''''''
623
624The ``ppc64abi32`` architecture has a number of issues which regularly
625tripped up the CI testing and was suspected to be quite broken. For that
626reason the maintainers strongly suspected no one actually used it.
627
628
629TCG introspection features
630--------------------------
631
632TCG trace-events (since 6.2)
633''''''''''''''''''''''''''''
634
635The ability to add new TCG trace points had bit rotted and as the
636feature can be replicated with TCG plugins it was removed. If
637any user is currently using this feature and needs help with
638converting to using TCG plugins they should contact the qemu-devel
639mailing list.
640
641
642System emulator devices
643-----------------------
644
645``spapr-pci-vfio-host-bridge`` (removed in 2.12)
646'''''''''''''''''''''''''''''''''''''''''''''''''
647
648The ``spapr-pci-vfio-host-bridge`` device type has been replaced by the
649``spapr-pci-host-bridge`` device type.
650
651``ivshmem`` (removed in 4.0)
652''''''''''''''''''''''''''''
653
654Replaced by either the ``ivshmem-plain`` or ``ivshmem-doorbell``.
655
656``ide-drive`` (removed in 6.0)
657''''''''''''''''''''''''''''''
658
659The 'ide-drive' device has been removed. Users should use 'ide-hd' or
660'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
661
662``scsi-disk`` (removed in 6.0)
663''''''''''''''''''''''''''''''
664
665The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or
666'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
667
668Related binaries
669----------------
670
671``qemu-nbd --partition`` (removed in 5.0)
672'''''''''''''''''''''''''''''''''''''''''
673
674The ``qemu-nbd --partition $digit`` code (also spelled ``-P``)
675could only handle MBR partitions, and never correctly handled logical
676partitions beyond partition 5.  Exporting a partition can still be
677done by utilizing the ``--image-opts`` option with a raw blockdev
678using the ``offset`` and ``size`` parameters layered on top of
679any other existing blockdev. For example, if partition 1 is 100MiB
680long starting at 1MiB, the old command::
681
682  qemu-nbd -t -P 1 -f qcow2 file.qcow2
683
684can be rewritten as::
685
686  qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2
687
688``qemu-img convert -n -o`` (removed in 5.1)
689'''''''''''''''''''''''''''''''''''''''''''
690
691All options specified in ``-o`` are image creation options, so
692they are now rejected when used with ``-n`` to skip image creation.
693
694
695``qemu-img create -b bad file $size`` (removed in 5.1)
696''''''''''''''''''''''''''''''''''''''''''''''''''''''
697
698When creating an image with a backing file that could not be opened,
699``qemu-img create`` used to issue a warning about the failure but
700proceed with the image creation if an explicit size was provided.
701However, as the ``-u`` option exists for this purpose, it is safer to
702enforce that any failure to open the backing image (including if the
703backing file is missing or an incorrect format was specified) is an
704error when ``-u`` is not used.
705
706``qemu-img amend`` to adjust backing file (removed in 6.1)
707''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
708
709The use of ``qemu-img amend`` to modify the name or format of a qcow2
710backing image was never fully documented or tested, and interferes
711with other amend operations that need access to the original backing
712image (such as deciding whether a v3 zero cluster may be left
713unallocated when converting to a v2 image).  Any changes to the
714backing chain should be performed with ``qemu-img rebase -u`` either
715before or after the remaining changes being performed by amend, as
716appropriate.
717
718``qemu-img`` backing file without format (removed in 6.1)
719'''''''''''''''''''''''''''''''''''''''''''''''''''''''''
720
721The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img
722convert`` to create or modify an image that depends on a backing file
723now requires that an explicit backing format be provided.  This is
724for safety: if QEMU probes a different format than what you thought,
725the data presented to the guest will be corrupt; similarly, presenting
726a raw image to a guest allows a potential security exploit if a future
727probe sees a non-raw image based on guest writes.
728
729To avoid creating unsafe backing chains, you must pass ``-o
730backing_fmt=`` (or the shorthand ``-F`` during create) to specify the
731intended backing format.  You may use ``qemu-img rebase -u`` to
732retroactively add a backing format to an existing image.  However, be
733aware that there are already potential security risks to blindly using
734``qemu-img info`` to probe the format of an untrusted backing image,
735when deciding what format to add into an existing image.
736
737Block devices
738-------------
739
740VXHS backend (removed in 5.1)
741'''''''''''''''''''''''''''''
742
743The VXHS code did not compile since v2.12.0. It was removed in 5.1.
744
745``sheepdog`` driver (removed in 6.0)
746''''''''''''''''''''''''''''''''''''
747
748The corresponding upstream server project is no longer maintained.
749Users are recommended to switch to an alternative distributed block
750device driver such as RBD.
751