xref: /qemu/docs/about/removed-features.rst (revision 29b62a10)
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22This option has been replaced by ``-net user,guestfwd=...``.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27``-net dump[,vlan=n][,file=filename][,len=maxlen]`` has been replaced by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
411Hexadecimal sizes with scaling multipliers (since 8.0)
412''''''''''''''''''''''''''''''''''''''''''''''''''''''
413
414Input parameters that take a size value should only use a size suffix
415(such as 'k' or 'M') when the base is written in decimal, and not when
416the value is hexadecimal.  That is, '0x20M' should be written either as
417'32M' or as '0x2000000'.
418
419``-chardev`` backend aliases ``tty`` and ``parport`` (removed in 8.0)
420'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
421
422``tty`` and ``parport`` used to be aliases for ``serial`` and ``parallel``
423respectively. The actual backend names should be used instead.
424
425QEMU Machine Protocol (QMP) commands
426------------------------------------
427
428``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2)
429''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
430
431The "autoload" parameter has been ignored since 2.12.0. All bitmaps
432are automatically loaded from qcow2 images.
433
434``cpu-add`` (removed in 5.2)
435''''''''''''''''''''''''''''
436
437Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
438documentation of ``query-hotpluggable-cpus`` for additional details.
439
440``change`` (removed in 6.0)
441'''''''''''''''''''''''''''
442
443Use ``blockdev-change-medium`` or ``change-vnc-password`` or
444``display-update`` instead.
445
446``query-events`` (removed in 6.0)
447'''''''''''''''''''''''''''''''''
448
449The ``query-events`` command has been superseded by the more powerful
450and accurate ``query-qmp-schema`` command.
451
452``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0)
453''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
454
455Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead.
456
457``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
458'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
459
460Use ``migrate_set_parameter`` instead.
461
462``query-cpus`` (removed in 6.0)
463'''''''''''''''''''''''''''''''
464
465The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command.
466
467``query-cpus-fast`` ``arch`` output member (removed in 6.0)
468'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
469
470The ``arch`` output member of the ``query-cpus-fast`` command is
471replaced by the ``target`` output member.
472
473chardev client socket with ``wait`` option (removed in 6.0)
474'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
475
476Character devices creating sockets in client mode should not specify
477the 'wait' field, which is only applicable to sockets in server mode
478
479``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0)
480''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
481
482Removed with no replacement.
483
484``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0)
485'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
486
487Removed with no replacement.
488
489``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0)
490'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
491
492The ``status`` field of the ``BlockDirtyInfo`` structure, returned by
493these commands is removed. Two new boolean fields, ``recording`` and
494``busy`` effectively replace it.
495
496``query-block`` result field ``dirty-bitmaps`` (removed in 6.0)
497'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
498
499The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
500the query-block command is itself now removed. The ``dirty-bitmaps``
501field of the ``BlockDeviceInfo`` struct should be used instead, which is the
502type of the ``inserted`` field in query-block replies, as well as the
503type of array items in query-named-block-nodes.
504
505``object-add`` option ``props`` (removed in 6.0)
506''''''''''''''''''''''''''''''''''''''''''''''''
507
508Specify the properties for the object as top-level arguments instead.
509
510``query-sgx`` return value member ``section-size`` (removed in 8.0)
511'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
512
513Member ``section-size`` in the return value of ``query-sgx``
514was superseded by ``sections``.
515
516
517``query-sgx-capabilities`` return value member ``section-size`` (removed in 8.0)
518''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
519
520Member ``section-size`` in the return value of ``query-sgx-capabilities``
521was superseded by ``sections``.
522
523Human Monitor Protocol (HMP) commands
524-------------------------------------
525
526``usb_add`` and ``usb_remove`` (removed in 2.12)
527''''''''''''''''''''''''''''''''''''''''''''''''
528
529Replaced by ``device_add`` and ``device_del`` (use ``device_add help`` for a
530list of available devices).
531
532``host_net_add`` and ``host_net_remove`` (removed in 2.12)
533''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
534
535Replaced by ``netdev_add`` and ``netdev_del``.
536
537The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0)
538'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
539
540The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and
541'hostfwd_remove' HMP commands has been replaced by ``netdev_id``.
542
543``cpu-add`` (removed in 5.2)
544''''''''''''''''''''''''''''
545
546Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
547documentation of ``query-hotpluggable-cpus`` for additional details.
548
549``change vnc TARGET`` (removed in 6.0)
550''''''''''''''''''''''''''''''''''''''
551
552No replacement.  The ``change vnc password`` and ``change DEVICE MEDIUM``
553commands are not affected.
554
555``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0)
556'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
557
558The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and
559``acl_remove`` commands were removed with no replacement. Authorization
560for VNC should be performed using the pluggable QAuthZ objects.
561
562``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0)
563'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
564
565Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead.
566
567``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
568'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
569
570Use ``migrate-set-parameters`` instead.
571
572``info cpustats`` (removed in 6.1)
573''''''''''''''''''''''''''''''''''
574
575This command didn't produce any output already. Removed with no replacement.
576
577Guest Emulator ISAs
578-------------------
579
580RISC-V ISA privilege specification version 1.09.1 (removed in 5.1)
581''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
582
583The RISC-V ISA privilege specification version 1.09.1 has been removed.
584QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
585should be used instead of the 1.09.1 version.
586
587System emulator CPUS
588--------------------
589
590KVM guest support on 32-bit Arm hosts (removed in 5.2)
591''''''''''''''''''''''''''''''''''''''''''''''''''''''
592
593The Linux kernel has dropped support for allowing 32-bit Arm systems
594to host KVM guests as of the 5.7 kernel, and was thus removed from QEMU
595as well.  Running 32-bit guests on a 64-bit Arm host remains supported.
596
597RISC-V ISA Specific CPUs (removed in 5.1)
598'''''''''''''''''''''''''''''''''''''''''
599
600The RISC-V cpus with the ISA version in the CPU name have been removed. The
601four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
602``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
603option when using the ``rv32`` or ``rv64`` CPUs.
604
605RISC-V no MMU CPUs (removed in 5.1)
606'''''''''''''''''''''''''''''''''''
607
608The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and
609``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified
610via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
611
612``compat`` property of server class POWER CPUs (removed in 6.0)
613'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
614
615The ``max-cpu-compat`` property of the ``pseries`` machine type should be used
616instead.
617
618``moxie`` CPU (removed in 6.1)
619''''''''''''''''''''''''''''''
620
621Nobody was using this CPU emulation in QEMU, and there were no test images
622available to make sure that the code is still working, so it has been removed
623without replacement.
624
625``lm32`` CPUs (removed in 6.1)
626''''''''''''''''''''''''''''''
627
628The only public user of this architecture was the milkymist project,
629which has been dead for years; there was never an upstream Linux
630port.  Removed without replacement.
631
632``unicore32`` CPUs (removed in 6.1)
633'''''''''''''''''''''''''''''''''''
634
635Support for this CPU was removed from the upstream Linux kernel, and
636there is no available upstream toolchain to build binaries for it.
637Removed without replacement.
638
639x86 ``Icelake-Client`` CPU (removed in 7.1)
640'''''''''''''''''''''''''''''''''''''''''''
641
642There isn't ever Icelake Client CPU, it is some wrong and imaginary one.
643Use ``Icelake-Server`` instead.
644
645System accelerators
646-------------------
647
648Userspace local APIC with KVM (x86, removed 8.0)
649''''''''''''''''''''''''''''''''''''''''''''''''
650
651``-M kernel-irqchip=off`` cannot be used on KVM if the CPU model includes
652a local APIC.  The ``split`` setting is supported, as is using ``-M
653kernel-irqchip=off`` when the CPU does not have a local APIC.
654
655System accelerators
656-------------------
657
658MIPS "Trap-and-Emulate" KVM support (removed in 8.0)
659''''''''''''''''''''''''''''''''''''''''''''''''''''
660
661The MIPS "Trap-and-Emulate" KVM host and guest support was removed
662from Linux in 2021, and is not supported anymore by QEMU either.
663
664System emulator machines
665------------------------
666
667``s390-virtio`` (removed in 2.6)
668''''''''''''''''''''''''''''''''
669
670Use the ``s390-ccw-virtio`` machine instead.
671
672The m68k ``dummy`` machine (removed in 2.9)
673'''''''''''''''''''''''''''''''''''''''''''
674
675Use the ``none`` machine with the ``loader`` device instead.
676
677``xlnx-ep108`` (removed in 3.0)
678'''''''''''''''''''''''''''''''
679
680The EP108 was an early access development board that is no longer used.
681Use the ``xlnx-zcu102`` machine instead.
682
683``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1)
684'''''''''''''''''''''''''''''''''''''''''''''''''''''
685
686The version specific Spike machines have been removed in favour of the
687generic ``spike`` machine. If you need to specify an older version of the RISC-V
688spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument.
689
690mips ``r4k`` platform (removed in 5.2)
691''''''''''''''''''''''''''''''''''''''
692
693This machine type was very old and unmaintained. Users should use the ``malta``
694machine type instead.
695
696mips ``fulong2e`` machine alias (removed in 6.0)
697''''''''''''''''''''''''''''''''''''''''''''''''
698
699This machine has been renamed ``fuloong2e``.
700
701``pc-0.10`` up to ``pc-1.3`` (removed in 4.0 up to 6.0)
702'''''''''''''''''''''''''''''''''''''''''''''''''''''''
703
704These machine types were very old and likely could not be used for live
705migration from old QEMU versions anymore. Use a newer machine type instead.
706
707Raspberry Pi ``raspi2`` and ``raspi3`` machines (removed in 6.2)
708''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
709
710The Raspberry Pi machines come in various models (A, A+, B, B+). To be able
711to distinguish which model QEMU is implementing, the ``raspi2`` and ``raspi3``
712machines have been renamed ``raspi2b`` and ``raspi3b``.
713
714Aspeed ``swift-bmc`` machine (removed in 7.0)
715'''''''''''''''''''''''''''''''''''''''''''''
716
717This machine was removed because it was unused. Alternative AST2500 based
718OpenPOWER machines are ``witherspoon-bmc`` and ``romulus-bmc``.
719
720ppc ``taihu`` machine (removed in 7.2)
721'''''''''''''''''''''''''''''''''''''''''''''
722
723This machine was removed because it was partially emulated and 405
724machines are very similar. Use the ``ref405ep`` machine instead.
725
726linux-user mode CPUs
727--------------------
728
729``tilegx`` CPUs (removed in 6.0)
730''''''''''''''''''''''''''''''''
731
732The ``tilegx`` guest CPU support has been removed without replacement. It was
733only implemented in linux-user mode, but support for this CPU was removed from
734the upstream Linux kernel in 2018, and it has also been dropped from glibc, so
735there is no new Linux development taking place with this architecture. For
736running the old binaries, you can use older versions of QEMU.
737
738``ppc64abi32`` CPUs (removed in 7.0)
739''''''''''''''''''''''''''''''''''''
740
741The ``ppc64abi32`` architecture has a number of issues which regularly
742tripped up the CI testing and was suspected to be quite broken. For that
743reason the maintainers strongly suspected no one actually used it.
744
745
746TCG introspection features
747--------------------------
748
749TCG trace-events (since 6.2)
750''''''''''''''''''''''''''''
751
752The ability to add new TCG trace points had bit rotted and as the
753feature can be replicated with TCG plugins it was removed. If
754any user is currently using this feature and needs help with
755converting to using TCG plugins they should contact the qemu-devel
756mailing list.
757
758
759System emulator devices
760-----------------------
761
762``spapr-pci-vfio-host-bridge`` (removed in 2.12)
763'''''''''''''''''''''''''''''''''''''''''''''''''
764
765The ``spapr-pci-vfio-host-bridge`` device type has been replaced by the
766``spapr-pci-host-bridge`` device type.
767
768``ivshmem`` (removed in 4.0)
769''''''''''''''''''''''''''''
770
771Replaced by either the ``ivshmem-plain`` or ``ivshmem-doorbell``.
772
773``ide-drive`` (removed in 6.0)
774''''''''''''''''''''''''''''''
775
776The 'ide-drive' device has been removed. Users should use 'ide-hd' or
777'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
778
779``scsi-disk`` (removed in 6.0)
780''''''''''''''''''''''''''''''
781
782The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or
783'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
784
785Related binaries
786----------------
787
788``qemu-nbd --partition`` (removed in 5.0)
789'''''''''''''''''''''''''''''''''''''''''
790
791The ``qemu-nbd --partition $digit`` code (also spelled ``-P``)
792could only handle MBR partitions, and never correctly handled logical
793partitions beyond partition 5.  Exporting a partition can still be
794done by utilizing the ``--image-opts`` option with a raw blockdev
795using the ``offset`` and ``size`` parameters layered on top of
796any other existing blockdev. For example, if partition 1 is 100MiB
797long starting at 1MiB, the old command::
798
799  qemu-nbd -t -P 1 -f qcow2 file.qcow2
800
801can be rewritten as::
802
803  qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2
804
805``qemu-img convert -n -o`` (removed in 5.1)
806'''''''''''''''''''''''''''''''''''''''''''
807
808All options specified in ``-o`` are image creation options, so
809they are now rejected when used with ``-n`` to skip image creation.
810
811
812``qemu-img create -b bad file $size`` (removed in 5.1)
813''''''''''''''''''''''''''''''''''''''''''''''''''''''
814
815When creating an image with a backing file that could not be opened,
816``qemu-img create`` used to issue a warning about the failure but
817proceed with the image creation if an explicit size was provided.
818However, as the ``-u`` option exists for this purpose, it is safer to
819enforce that any failure to open the backing image (including if the
820backing file is missing or an incorrect format was specified) is an
821error when ``-u`` is not used.
822
823``qemu-img amend`` to adjust backing file (removed in 6.1)
824''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
825
826The use of ``qemu-img amend`` to modify the name or format of a qcow2
827backing image was never fully documented or tested, and interferes
828with other amend operations that need access to the original backing
829image (such as deciding whether a v3 zero cluster may be left
830unallocated when converting to a v2 image).  Any changes to the
831backing chain should be performed with ``qemu-img rebase -u`` either
832before or after the remaining changes being performed by amend, as
833appropriate.
834
835``qemu-img`` backing file without format (removed in 6.1)
836'''''''''''''''''''''''''''''''''''''''''''''''''''''''''
837
838The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img
839convert`` to create or modify an image that depends on a backing file
840now requires that an explicit backing format be provided.  This is
841for safety: if QEMU probes a different format than what you thought,
842the data presented to the guest will be corrupt; similarly, presenting
843a raw image to a guest allows a potential security exploit if a future
844probe sees a non-raw image based on guest writes.
845
846To avoid creating unsafe backing chains, you must pass ``-o
847backing_fmt=`` (or the shorthand ``-F`` during create) to specify the
848intended backing format.  You may use ``qemu-img rebase -u`` to
849retroactively add a backing format to an existing image.  However, be
850aware that there are already potential security risks to blindly using
851``qemu-img info`` to probe the format of an untrusted backing image,
852when deciding what format to add into an existing image.
853
854Block devices
855-------------
856
857VXHS backend (removed in 5.1)
858'''''''''''''''''''''''''''''
859
860The VXHS code did not compile since v2.12.0. It was removed in 5.1.
861
862``sheepdog`` driver (removed in 6.0)
863''''''''''''''''''''''''''''''''''''
864
865The corresponding upstream server project is no longer maintained.
866Users are recommended to switch to an alternative distributed block
867device driver such as RBD.
868