xref: /qemu/docs/about/removed-features.rst (revision 75ac231c)
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22This option has been replaced by ``-net user,guestfwd=...``.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27``-net dump[,vlan=n][,file=filename][,len=maxlen]`` has been replaced by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
351``-writeconfig`` (removed in 7.1)
352'''''''''''''''''''''''''''''''''
353
354The ``-writeconfig`` option was not able to serialize the entire contents
355of the QEMU command line.  It is thus considered a failed experiment
356and removed without a replacement.
357
358``loaded`` property of ``secret`` and ``secret_keyring`` objects (removed in 7.1)
359'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
360
361The ``loaded=on`` option in the command line or QMP ``object-add`` either had
362no effect (if ``loaded`` was the last option) or caused options to be
363effectively ignored as if they were not given.  The property is therefore
364useless and should simply be removed.
365
366``opened`` property of ``rng-*`` objects (removed in 7.1)
367'''''''''''''''''''''''''''''''''''''''''''''''''''''''''
368
369The ``opened=on`` option in the command line or QMP ``object-add`` either had
370no effect (if ``opened`` was the last option) or caused errors.  The property
371is therefore useless and should simply be removed.
372
373``-display sdl,window_close=...`` (removed in 7.1)
374''''''''''''''''''''''''''''''''''''''''''''''''''
375
376Use ``-display sdl,window-close=...`` instead (i.e. with a minus instead of
377an underscore between "window" and "close").
378
379``-alt-grab`` and ``-display sdl,alt_grab=on`` (removed in 7.1)
380'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
381
382Use ``-display sdl,grab-mod=lshift-lctrl-lalt`` instead.
383
384``-ctrl-grab`` and ``-display sdl,ctrl_grab=on`` (removed in 7.1)
385'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
386
387Use ``-display sdl,grab-mod=rctrl`` instead.
388
389``-sdl`` (removed in 7.1)
390'''''''''''''''''''''''''
391
392Use ``-display sdl`` instead.
393
394``-curses`` (removed in 7.1)
395''''''''''''''''''''''''''''
396
397Use ``-display curses`` instead.
398
399Creating sound card devices using ``-soundhw`` (removed in 7.1)
400'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
401
402Sound card devices should be created using ``-device`` or ``-audio``.
403The exception is ``pcspk`` which can be activated using ``-machine
404pcspk-audiodev=<name>``.
405
406``-watchdog`` (since 7.2)
407'''''''''''''''''''''''''
408
409Use ``-device`` instead.
410
411
412QEMU Machine Protocol (QMP) commands
413------------------------------------
414
415``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2)
416''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
417
418The "autoload" parameter has been ignored since 2.12.0. All bitmaps
419are automatically loaded from qcow2 images.
420
421``cpu-add`` (removed in 5.2)
422''''''''''''''''''''''''''''
423
424Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
425documentation of ``query-hotpluggable-cpus`` for additional details.
426
427``change`` (removed in 6.0)
428'''''''''''''''''''''''''''
429
430Use ``blockdev-change-medium`` or ``change-vnc-password`` or
431``display-update`` instead.
432
433``query-events`` (removed in 6.0)
434'''''''''''''''''''''''''''''''''
435
436The ``query-events`` command has been superseded by the more powerful
437and accurate ``query-qmp-schema`` command.
438
439``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0)
440''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
441
442Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead.
443
444``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
445'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
446
447Use ``migrate_set_parameter`` instead.
448
449``query-cpus`` (removed in 6.0)
450'''''''''''''''''''''''''''''''
451
452The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command.
453
454``query-cpus-fast`` ``arch`` output member (removed in 6.0)
455'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
456
457The ``arch`` output member of the ``query-cpus-fast`` command is
458replaced by the ``target`` output member.
459
460chardev client socket with ``wait`` option (removed in 6.0)
461'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
462
463Character devices creating sockets in client mode should not specify
464the 'wait' field, which is only applicable to sockets in server mode
465
466``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0)
467''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
468
469Removed with no replacement.
470
471``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0)
472'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
473
474Removed with no replacement.
475
476``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0)
477'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
478
479The ``status`` field of the ``BlockDirtyInfo`` structure, returned by
480these commands is removed. Two new boolean fields, ``recording`` and
481``busy`` effectively replace it.
482
483``query-block`` result field ``dirty-bitmaps`` (removed in 6.0)
484'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
485
486The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
487the query-block command is itself now removed. The ``dirty-bitmaps``
488field of the ``BlockDeviceInfo`` struct should be used instead, which is the
489type of the ``inserted`` field in query-block replies, as well as the
490type of array items in query-named-block-nodes.
491
492``object-add`` option ``props`` (removed in 6.0)
493''''''''''''''''''''''''''''''''''''''''''''''''
494
495Specify the properties for the object as top-level arguments instead.
496
497Human Monitor Protocol (HMP) commands
498-------------------------------------
499
500``usb_add`` and ``usb_remove`` (removed in 2.12)
501''''''''''''''''''''''''''''''''''''''''''''''''
502
503Replaced by ``device_add`` and ``device_del`` (use ``device_add help`` for a
504list of available devices).
505
506``host_net_add`` and ``host_net_remove`` (removed in 2.12)
507''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
508
509Replaced by ``netdev_add`` and ``netdev_del``.
510
511The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0)
512'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
513
514The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and
515'hostfwd_remove' HMP commands has been replaced by ``netdev_id``.
516
517``cpu-add`` (removed in 5.2)
518''''''''''''''''''''''''''''
519
520Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
521documentation of ``query-hotpluggable-cpus`` for additional details.
522
523``change vnc TARGET`` (removed in 6.0)
524''''''''''''''''''''''''''''''''''''''
525
526No replacement.  The ``change vnc password`` and ``change DEVICE MEDIUM``
527commands are not affected.
528
529``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0)
530'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
531
532The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and
533``acl_remove`` commands were removed with no replacement. Authorization
534for VNC should be performed using the pluggable QAuthZ objects.
535
536``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0)
537'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
538
539Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead.
540
541``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
542'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
543
544Use ``migrate-set-parameters`` instead.
545
546``info cpustats`` (removed in 6.1)
547''''''''''''''''''''''''''''''''''
548
549This command didn't produce any output already. Removed with no replacement.
550
551Guest Emulator ISAs
552-------------------
553
554RISC-V ISA privilege specification version 1.09.1 (removed in 5.1)
555''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
556
557The RISC-V ISA privilege specification version 1.09.1 has been removed.
558QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
559should be used instead of the 1.09.1 version.
560
561System emulator CPUS
562--------------------
563
564KVM guest support on 32-bit Arm hosts (removed in 5.2)
565''''''''''''''''''''''''''''''''''''''''''''''''''''''
566
567The Linux kernel has dropped support for allowing 32-bit Arm systems
568to host KVM guests as of the 5.7 kernel. Accordingly, QEMU is deprecating
569its support for this configuration and will remove it in a future version.
570Running 32-bit guests on a 64-bit Arm host remains supported.
571
572RISC-V ISA Specific CPUs (removed in 5.1)
573'''''''''''''''''''''''''''''''''''''''''
574
575The RISC-V cpus with the ISA version in the CPU name have been removed. The
576four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
577``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
578option when using the ``rv32`` or ``rv64`` CPUs.
579
580RISC-V no MMU CPUs (removed in 5.1)
581'''''''''''''''''''''''''''''''''''
582
583The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and
584``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified
585via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
586
587``compat`` property of server class POWER CPUs (removed in 6.0)
588'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
589
590The ``max-cpu-compat`` property of the ``pseries`` machine type should be used
591instead.
592
593``moxie`` CPU (removed in 6.1)
594''''''''''''''''''''''''''''''
595
596Nobody was using this CPU emulation in QEMU, and there were no test images
597available to make sure that the code is still working, so it has been removed
598without replacement.
599
600``lm32`` CPUs (removed in 6.1)
601''''''''''''''''''''''''''''''
602
603The only public user of this architecture was the milkymist project,
604which has been dead for years; there was never an upstream Linux
605port.  Removed without replacement.
606
607``unicore32`` CPUs (removed in 6.1)
608'''''''''''''''''''''''''''''''''''
609
610Support for this CPU was removed from the upstream Linux kernel, and
611there is no available upstream toolchain to build binaries for it.
612Removed without replacement.
613
614x86 ``Icelake-Client`` CPU (removed in 7.1)
615'''''''''''''''''''''''''''''''''''''''''''
616
617There isn't ever Icelake Client CPU, it is some wrong and imaginary one.
618Use ``Icelake-Server`` instead.
619
620System emulator machines
621------------------------
622
623``s390-virtio`` (removed in 2.6)
624''''''''''''''''''''''''''''''''
625
626Use the ``s390-ccw-virtio`` machine instead.
627
628The m68k ``dummy`` machine (removed in 2.9)
629'''''''''''''''''''''''''''''''''''''''''''
630
631Use the ``none`` machine with the ``loader`` device instead.
632
633``xlnx-ep108`` (removed in 3.0)
634'''''''''''''''''''''''''''''''
635
636The EP108 was an early access development board that is no longer used.
637Use the ``xlnx-zcu102`` machine instead.
638
639``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1)
640'''''''''''''''''''''''''''''''''''''''''''''''''''''
641
642The version specific Spike machines have been removed in favour of the
643generic ``spike`` machine. If you need to specify an older version of the RISC-V
644spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument.
645
646mips ``r4k`` platform (removed in 5.2)
647''''''''''''''''''''''''''''''''''''''
648
649This machine type was very old and unmaintained. Users should use the ``malta``
650machine type instead.
651
652mips ``fulong2e`` machine alias (removed in 6.0)
653''''''''''''''''''''''''''''''''''''''''''''''''
654
655This machine has been renamed ``fuloong2e``.
656
657``pc-0.10`` up to ``pc-1.3`` (removed in 4.0 up to 6.0)
658'''''''''''''''''''''''''''''''''''''''''''''''''''''''
659
660These machine types were very old and likely could not be used for live
661migration from old QEMU versions anymore. Use a newer machine type instead.
662
663Raspberry Pi ``raspi2`` and ``raspi3`` machines (removed in 6.2)
664''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
665
666The Raspberry Pi machines come in various models (A, A+, B, B+). To be able
667to distinguish which model QEMU is implementing, the ``raspi2`` and ``raspi3``
668machines have been renamed ``raspi2b`` and ``raspi3b``.
669
670Aspeed ``swift-bmc`` machine (removed in 7.0)
671'''''''''''''''''''''''''''''''''''''''''''''
672
673This machine was removed because it was unused. Alternative AST2500 based
674OpenPOWER machines are ``witherspoon-bmc`` and ``romulus-bmc``.
675
676ppc ``taihu`` machine (removed in 7.2)
677'''''''''''''''''''''''''''''''''''''''''''''
678
679This machine was removed because it was partially emulated and 405
680machines are very similar. Use the ``ref405ep`` machine instead.
681
682linux-user mode CPUs
683--------------------
684
685``tilegx`` CPUs (removed in 6.0)
686''''''''''''''''''''''''''''''''
687
688The ``tilegx`` guest CPU support has been removed without replacement. It was
689only implemented in linux-user mode, but support for this CPU was removed from
690the upstream Linux kernel in 2018, and it has also been dropped from glibc, so
691there is no new Linux development taking place with this architecture. For
692running the old binaries, you can use older versions of QEMU.
693
694``ppc64abi32`` CPUs (removed in 7.0)
695''''''''''''''''''''''''''''''''''''
696
697The ``ppc64abi32`` architecture has a number of issues which regularly
698tripped up the CI testing and was suspected to be quite broken. For that
699reason the maintainers strongly suspected no one actually used it.
700
701
702TCG introspection features
703--------------------------
704
705TCG trace-events (since 6.2)
706''''''''''''''''''''''''''''
707
708The ability to add new TCG trace points had bit rotted and as the
709feature can be replicated with TCG plugins it was removed. If
710any user is currently using this feature and needs help with
711converting to using TCG plugins they should contact the qemu-devel
712mailing list.
713
714
715System emulator devices
716-----------------------
717
718``spapr-pci-vfio-host-bridge`` (removed in 2.12)
719'''''''''''''''''''''''''''''''''''''''''''''''''
720
721The ``spapr-pci-vfio-host-bridge`` device type has been replaced by the
722``spapr-pci-host-bridge`` device type.
723
724``ivshmem`` (removed in 4.0)
725''''''''''''''''''''''''''''
726
727Replaced by either the ``ivshmem-plain`` or ``ivshmem-doorbell``.
728
729``ide-drive`` (removed in 6.0)
730''''''''''''''''''''''''''''''
731
732The 'ide-drive' device has been removed. Users should use 'ide-hd' or
733'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
734
735``scsi-disk`` (removed in 6.0)
736''''''''''''''''''''''''''''''
737
738The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or
739'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
740
741Related binaries
742----------------
743
744``qemu-nbd --partition`` (removed in 5.0)
745'''''''''''''''''''''''''''''''''''''''''
746
747The ``qemu-nbd --partition $digit`` code (also spelled ``-P``)
748could only handle MBR partitions, and never correctly handled logical
749partitions beyond partition 5.  Exporting a partition can still be
750done by utilizing the ``--image-opts`` option with a raw blockdev
751using the ``offset`` and ``size`` parameters layered on top of
752any other existing blockdev. For example, if partition 1 is 100MiB
753long starting at 1MiB, the old command::
754
755  qemu-nbd -t -P 1 -f qcow2 file.qcow2
756
757can be rewritten as::
758
759  qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2
760
761``qemu-img convert -n -o`` (removed in 5.1)
762'''''''''''''''''''''''''''''''''''''''''''
763
764All options specified in ``-o`` are image creation options, so
765they are now rejected when used with ``-n`` to skip image creation.
766
767
768``qemu-img create -b bad file $size`` (removed in 5.1)
769''''''''''''''''''''''''''''''''''''''''''''''''''''''
770
771When creating an image with a backing file that could not be opened,
772``qemu-img create`` used to issue a warning about the failure but
773proceed with the image creation if an explicit size was provided.
774However, as the ``-u`` option exists for this purpose, it is safer to
775enforce that any failure to open the backing image (including if the
776backing file is missing or an incorrect format was specified) is an
777error when ``-u`` is not used.
778
779``qemu-img amend`` to adjust backing file (removed in 6.1)
780''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
781
782The use of ``qemu-img amend`` to modify the name or format of a qcow2
783backing image was never fully documented or tested, and interferes
784with other amend operations that need access to the original backing
785image (such as deciding whether a v3 zero cluster may be left
786unallocated when converting to a v2 image).  Any changes to the
787backing chain should be performed with ``qemu-img rebase -u`` either
788before or after the remaining changes being performed by amend, as
789appropriate.
790
791``qemu-img`` backing file without format (removed in 6.1)
792'''''''''''''''''''''''''''''''''''''''''''''''''''''''''
793
794The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img
795convert`` to create or modify an image that depends on a backing file
796now requires that an explicit backing format be provided.  This is
797for safety: if QEMU probes a different format than what you thought,
798the data presented to the guest will be corrupt; similarly, presenting
799a raw image to a guest allows a potential security exploit if a future
800probe sees a non-raw image based on guest writes.
801
802To avoid creating unsafe backing chains, you must pass ``-o
803backing_fmt=`` (or the shorthand ``-F`` during create) to specify the
804intended backing format.  You may use ``qemu-img rebase -u`` to
805retroactively add a backing format to an existing image.  However, be
806aware that there are already potential security risks to blindly using
807``qemu-img info`` to probe the format of an untrusted backing image,
808when deciding what format to add into an existing image.
809
810Block devices
811-------------
812
813VXHS backend (removed in 5.1)
814'''''''''''''''''''''''''''''
815
816The VXHS code did not compile since v2.12.0. It was removed in 5.1.
817
818``sheepdog`` driver (removed in 6.0)
819''''''''''''''''''''''''''''''''''''
820
821The corresponding upstream server project is no longer maintained.
822Users are recommended to switch to an alternative distributed block
823device driver such as RBD.
824