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22This option has been replaced by ``-net user,guestfwd=...``.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27``-net dump[,vlan=n][,file=filename][,len=maxlen]`` has been replaced by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
333QEMU Machine Protocol (QMP) commands
334------------------------------------
335
336``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2)
337''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
338
339The "autoload" parameter has been ignored since 2.12.0. All bitmaps
340are automatically loaded from qcow2 images.
341
342``cpu-add`` (removed in 5.2)
343''''''''''''''''''''''''''''
344
345Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
346documentation of ``query-hotpluggable-cpus`` for additional details.
347
348``change`` (removed in 6.0)
349'''''''''''''''''''''''''''
350
351Use ``blockdev-change-medium`` or ``change-vnc-password`` instead.
352
353``query-events`` (removed in 6.0)
354'''''''''''''''''''''''''''''''''
355
356The ``query-events`` command has been superseded by the more powerful
357and accurate ``query-qmp-schema`` command.
358
359``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0)
360''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
361
362Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead.
363
364``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
365'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
366
367Use ``migrate_set_parameter`` instead.
368
369``query-cpus`` (removed in 6.0)
370'''''''''''''''''''''''''''''''
371
372The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command.
373
374``query-cpus-fast`` ``arch`` output member (removed in 6.0)
375'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
376
377The ``arch`` output member of the ``query-cpus-fast`` command is
378replaced by the ``target`` output member.
379
380chardev client socket with ``wait`` option (removed in 6.0)
381'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
382
383Character devices creating sockets in client mode should not specify
384the 'wait' field, which is only applicable to sockets in server mode
385
386``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0)
387''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
388
389Removed with no replacement.
390
391``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0)
392'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
393
394Removed with no replacement.
395
396``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0)
397'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
398
399The ``status`` field of the ``BlockDirtyInfo`` structure, returned by
400these commands is removed. Two new boolean fields, ``recording`` and
401``busy`` effectively replace it.
402
403``query-block`` result field ``dirty-bitmaps`` (removed in 6.0)
404'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
405
406The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by
407the query-block command is itself now removed. The ``dirty-bitmaps``
408field of the ``BlockDeviceInfo`` struct should be used instead, which is the
409type of the ``inserted`` field in query-block replies, as well as the
410type of array items in query-named-block-nodes.
411
412``object-add`` option ``props`` (removed in 6.0)
413''''''''''''''''''''''''''''''''''''''''''''''''
414
415Specify the properties for the object as top-level arguments instead.
416
417Human Monitor Protocol (HMP) commands
418-------------------------------------
419
420``usb_add`` and ``usb_remove`` (removed in 2.12)
421''''''''''''''''''''''''''''''''''''''''''''''''
422
423Replaced by ``device_add`` and ``device_del`` (use ``device_add help`` for a
424list of available devices).
425
426``host_net_add`` and ``host_net_remove`` (removed in 2.12)
427''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
428
429Replaced by ``netdev_add`` and ``netdev_del``.
430
431The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0)
432'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
433
434The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and
435'hostfwd_remove' HMP commands has been replaced by ``netdev_id``.
436
437``cpu-add`` (removed in 5.2)
438''''''''''''''''''''''''''''
439
440Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``.  See
441documentation of ``query-hotpluggable-cpus`` for additional details.
442
443``change vnc TARGET`` (removed in 6.0)
444''''''''''''''''''''''''''''''''''''''
445
446No replacement.  The ``change vnc password`` and ``change DEVICE MEDIUM``
447commands are not affected.
448
449``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0)
450'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
451
452The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and
453``acl_remove`` commands were removed with no replacement. Authorization
454for VNC should be performed using the pluggable QAuthZ objects.
455
456``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0)
457'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
458
459Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead.
460
461``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0)
462'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
463
464Use ``migrate-set-parameters`` instead.
465
466``info cpustats`` (removed in 6.1)
467''''''''''''''''''''''''''''''''''
468
469This command didn't produce any output already. Removed with no replacement.
470
471Guest Emulator ISAs
472-------------------
473
474RISC-V ISA privilege specification version 1.09.1 (removed in 5.1)
475''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
476
477The RISC-V ISA privilege specification version 1.09.1 has been removed.
478QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these
479should be used instead of the 1.09.1 version.
480
481System emulator CPUS
482--------------------
483
484KVM guest support on 32-bit Arm hosts (removed in 5.2)
485''''''''''''''''''''''''''''''''''''''''''''''''''''''
486
487The Linux kernel has dropped support for allowing 32-bit Arm systems
488to host KVM guests as of the 5.7 kernel. Accordingly, QEMU is deprecating
489its support for this configuration and will remove it in a future version.
490Running 32-bit guests on a 64-bit Arm host remains supported.
491
492RISC-V ISA Specific CPUs (removed in 5.1)
493'''''''''''''''''''''''''''''''''''''''''
494
495The RISC-V cpus with the ISA version in the CPU name have been removed. The
496four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and
497``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec``
498option when using the ``rv32`` or ``rv64`` CPUs.
499
500RISC-V no MMU CPUs (removed in 5.1)
501'''''''''''''''''''''''''''''''''''
502
503The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and
504``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified
505via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs.
506
507``compat`` property of server class POWER CPUs (removed in 6.0)
508'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
509
510The ``max-cpu-compat`` property of the ``pseries`` machine type should be used
511instead.
512
513``moxie`` CPU (removed in 6.1)
514''''''''''''''''''''''''''''''
515
516Nobody was using this CPU emulation in QEMU, and there were no test images
517available to make sure that the code is still working, so it has been removed
518without replacement.
519
520``lm32`` CPUs (removed in 6.1)
521''''''''''''''''''''''''''''''
522
523The only public user of this architecture was the milkymist project,
524which has been dead for years; there was never an upstream Linux
525port.  Removed without replacement.
526
527``unicore32`` CPUs (removed in 6.1)
528'''''''''''''''''''''''''''''''''''
529
530Support for this CPU was removed from the upstream Linux kernel, and
531there is no available upstream toolchain to build binaries for it.
532Removed without replacement.
533
534System emulator machines
535------------------------
536
537``s390-virtio`` (removed in 2.6)
538''''''''''''''''''''''''''''''''
539
540Use the ``s390-ccw-virtio`` machine instead.
541
542The m68k ``dummy`` machine (removed in 2.9)
543'''''''''''''''''''''''''''''''''''''''''''
544
545Use the ``none`` machine with the ``loader`` device instead.
546
547``xlnx-ep108`` (removed in 3.0)
548'''''''''''''''''''''''''''''''
549
550The EP108 was an early access development board that is no longer used.
551Use the ``xlnx-zcu102`` machine instead.
552
553``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1)
554'''''''''''''''''''''''''''''''''''''''''''''''''''''
555
556The version specific Spike machines have been removed in favour of the
557generic ``spike`` machine. If you need to specify an older version of the RISC-V
558spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument.
559
560mips ``r4k`` platform (removed in 5.2)
561''''''''''''''''''''''''''''''''''''''
562
563This machine type was very old and unmaintained. Users should use the ``malta``
564machine type instead.
565
566mips ``fulong2e`` machine alias (removed in 6.0)
567''''''''''''''''''''''''''''''''''''''''''''''''
568
569This machine has been renamed ``fuloong2e``.
570
571``pc-0.10`` up to ``pc-1.3`` (removed in 4.0 up to 6.0)
572'''''''''''''''''''''''''''''''''''''''''''''''''''''''
573
574These machine types were very old and likely could not be used for live
575migration from old QEMU versions anymore. Use a newer machine type instead.
576
577Raspberry Pi ``raspi2`` and ``raspi3`` machines (removed in 6.2)
578''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
579
580The Raspberry Pi machines come in various models (A, A+, B, B+). To be able
581to distinguish which model QEMU is implementing, the ``raspi2`` and ``raspi3``
582machines have been renamed ``raspi2b`` and ``raspi3b``.
583
584
585linux-user mode CPUs
586--------------------
587
588``tilegx`` CPUs (removed in 6.0)
589''''''''''''''''''''''''''''''''
590
591The ``tilegx`` guest CPU support has been removed without replacement. It was
592only implemented in linux-user mode, but support for this CPU was removed from
593the upstream Linux kernel in 2018, and it has also been dropped from glibc, so
594there is no new Linux development taking place with this architecture. For
595running the old binaries, you can use older versions of QEMU.
596
597System emulator devices
598-----------------------
599
600``spapr-pci-vfio-host-bridge`` (removed in 2.12)
601'''''''''''''''''''''''''''''''''''''''''''''''''
602
603The ``spapr-pci-vfio-host-bridge`` device type has been replaced by the
604``spapr-pci-host-bridge`` device type.
605
606``ivshmem`` (removed in 4.0)
607''''''''''''''''''''''''''''
608
609Replaced by either the ``ivshmem-plain`` or ``ivshmem-doorbell``.
610
611``ide-drive`` (removed in 6.0)
612''''''''''''''''''''''''''''''
613
614The 'ide-drive' device has been removed. Users should use 'ide-hd' or
615'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed.
616
617``scsi-disk`` (removed in 6.0)
618''''''''''''''''''''''''''''''
619
620The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or
621'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed.
622
623Related binaries
624----------------
625
626``qemu-nbd --partition`` (removed in 5.0)
627'''''''''''''''''''''''''''''''''''''''''
628
629The ``qemu-nbd --partition $digit`` code (also spelled ``-P``)
630could only handle MBR partitions, and never correctly handled logical
631partitions beyond partition 5.  Exporting a partition can still be
632done by utilizing the ``--image-opts`` option with a raw blockdev
633using the ``offset`` and ``size`` parameters layered on top of
634any other existing blockdev. For example, if partition 1 is 100MiB
635long starting at 1MiB, the old command::
636
637  qemu-nbd -t -P 1 -f qcow2 file.qcow2
638
639can be rewritten as::
640
641  qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2
642
643``qemu-img convert -n -o`` (removed in 5.1)
644'''''''''''''''''''''''''''''''''''''''''''
645
646All options specified in ``-o`` are image creation options, so
647they are now rejected when used with ``-n`` to skip image creation.
648
649
650``qemu-img create -b bad file $size`` (removed in 5.1)
651''''''''''''''''''''''''''''''''''''''''''''''''''''''
652
653When creating an image with a backing file that could not be opened,
654``qemu-img create`` used to issue a warning about the failure but
655proceed with the image creation if an explicit size was provided.
656However, as the ``-u`` option exists for this purpose, it is safer to
657enforce that any failure to open the backing image (including if the
658backing file is missing or an incorrect format was specified) is an
659error when ``-u`` is not used.
660
661qemu-img amend to adjust backing file (removed in 6.1)
662''''''''''''''''''''''''''''''''''''''''''''''''''''''
663
664The use of ``qemu-img amend`` to modify the name or format of a qcow2
665backing image was never fully documented or tested, and interferes
666with other amend operations that need access to the original backing
667image (such as deciding whether a v3 zero cluster may be left
668unallocated when converting to a v2 image).  Any changes to the
669backing chain should be performed with ``qemu-img rebase -u`` either
670before or after the remaining changes being performed by amend, as
671appropriate.
672
673qemu-img backing file without format (removed in 6.1)
674'''''''''''''''''''''''''''''''''''''''''''''''''''''
675
676The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img
677convert`` to create or modify an image that depends on a backing file
678now requires that an explicit backing format be provided.  This is
679for safety: if QEMU probes a different format than what you thought,
680the data presented to the guest will be corrupt; similarly, presenting
681a raw image to a guest allows a potential security exploit if a future
682probe sees a non-raw image based on guest writes.
683
684To avoid creating unsafe backing chains, you must pass ``-o
685backing_fmt=`` (or the shorthand ``-F`` during create) to specify the
686intended backing format.  You may use ``qemu-img rebase -u`` to
687retroactively add a backing format to an existing image.  However, be
688aware that there are already potential security risks to blindly using
689``qemu-img info`` to probe the format of an untrusted backing image,
690when deciding what format to add into an existing image.
691
692Block devices
693-------------
694
695VXHS backend (removed in 5.1)
696'''''''''''''''''''''''''''''
697
698The VXHS code did not compile since v2.12.0. It was removed in 5.1.
699
700``sheepdog`` driver (removed in 6.0)
701''''''''''''''''''''''''''''''''''''
702
703The corresponding upstream server project is no longer maintained.
704Users are recommended to switch to an alternative distributed block
705device driver such as RBD.
706