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Commit | Line | Data |
---|---|---|
2c5060cd TH |
1 | |
2 | Removed features | |
3 | ================ | |
4 | ||
5 | What follows is a record of recently removed, formerly deprecated | |
6 | features that serves as a record for users who have encountered | |
7 | trouble after a recent upgrade. | |
8 | ||
9 | System emulator command line arguments | |
10 | -------------------------------------- | |
11 | ||
12 | ``-net ...,name=``\ *name* (removed in 5.1) | |
13 | ''''''''''''''''''''''''''''''''''''''''''' | |
14 | ||
15 | The ``name`` parameter of the ``-net`` option was a synonym | |
16 | for the ``id`` parameter, which should now be used instead. | |
17 | ||
18 | ``-no-kvm`` (removed in 5.2) | |
19 | '''''''''''''''''''''''''''' | |
20 | ||
21 | The ``-no-kvm`` argument was a synonym for setting ``-machine accel=tcg``. | |
22 | ||
c8c9dc42 TH |
23 | ``-realtime`` (removed in 6.0) |
24 | '''''''''''''''''''''''''''''' | |
25 | ||
26 | The ``-realtime mlock=on|off`` argument has been replaced by the | |
27 | ``-overcommit mem-lock=on|off`` argument. | |
28 | ||
e2680403 TH |
29 | ``-show-cursor`` option (removed in 6.0) |
30 | '''''''''''''''''''''''''''''''''''''''' | |
90d6a086 TH |
31 | |
32 | Use ``-display sdl,show-cursor=on``, ``-display gtk,show-cursor=on`` | |
33 | or ``-display default,show-cursor=on`` instead. | |
34 | ||
2c5060cd TH |
35 | ``-tb-size`` option (removed in 6.0) |
36 | '''''''''''''''''''''''''''''''''''' | |
37 | ||
38 | QEMU 5.0 introduced an alternative syntax to specify the size of the translation | |
39 | block cache, ``-accel tcg,tb-size=``. | |
40 | ||
6db34277 TH |
41 | ``-usbdevice audio`` (removed in 6.0) |
42 | ''''''''''''''''''''''''''''''''''''' | |
43 | ||
44 | This option lacked the possibility to specify an audio backend device. | |
45 | Use ``-device usb-audio`` now instead (and specify a corresponding USB | |
46 | host controller or ``-usb`` if necessary). | |
47 | ||
5994dcb8 DB |
48 | ``-vnc acl`` (removed in 6.0) |
49 | ''''''''''''''''''''''''''''' | |
50 | ||
51 | The ``acl`` option to the ``-vnc`` argument has been replaced | |
52 | by the ``tls-authz`` and ``sasl-authz`` options. | |
6db34277 | 53 | |
283d845c DB |
54 | ``-mon ...,control=readline,pretty=on|off`` (removed in 6.0) |
55 | '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
56 | ||
57 | The ``pretty=on|off`` switch has no effect for HMP monitors and | |
58 | its use is rejected. | |
59 | ||
8d17adf3 DB |
60 | ``-drive file=json:{...{'driver':'file'}}`` (removed 6.0) |
61 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
62 | ||
63 | The 'file' driver for drives is no longer appropriate for character or host | |
64 | devices and will only accept regular files (S_IFREG). The correct driver | |
65 | for these file types is 'host_cdrom' or 'host_device' as appropriate. | |
66 | ||
36585e2b MA |
67 | Floppy controllers' drive properties (removed in 6.0) |
68 | ''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
69 | ||
70 | Use ``-device floppy,...`` instead. When configuring onboard floppy | |
71 | controllers | |
72 | :: | |
73 | ||
74 | -global isa-fdc.driveA=... | |
75 | -global sysbus-fdc.driveA=... | |
76 | -global SUNW,fdtwo.drive=... | |
77 | ||
78 | become | |
79 | :: | |
80 | ||
81 | -device floppy,unit=0,drive=... | |
82 | ||
83 | and | |
84 | :: | |
85 | ||
86 | -global isa-fdc.driveB=... | |
87 | -global sysbus-fdc.driveB=... | |
88 | ||
89 | become | |
90 | :: | |
91 | ||
92 | -device floppy,unit=1,drive=... | |
93 | ||
94 | When plugging in a floppy controller | |
95 | :: | |
96 | ||
97 | -device isa-fdc,...,driveA=... | |
98 | ||
99 | becomes | |
100 | :: | |
101 | ||
102 | -device isa-fdc,... | |
103 | -device floppy,unit=0,drive=... | |
104 | ||
105 | and | |
106 | :: | |
107 | ||
108 | -device isa-fdc,...,driveB=... | |
109 | ||
110 | becomes | |
111 | :: | |
112 | ||
113 | -device isa-fdc,... | |
114 | -device floppy,unit=1,drive=... | |
115 | ||
fe9f70a1 MA |
116 | ``-drive`` with bogus interface type (removed in 6.0) |
117 | ''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
118 | ||
119 | Drives with interface types other than ``if=none`` are for onboard | |
120 | devices. Drives the board doesn't pick up can no longer be used with | |
121 | -device. Use ``if=none`` instead. | |
122 | ||
d2aea775 TH |
123 | ``-usbdevice ccid`` (removed in 6.0) |
124 | ''''''''''''''''''''''''''''''''''''' | |
125 | ||
126 | This option was undocumented and not used in the field. | |
1662ea9f | 127 | Use ``-device usb-ccid`` instead. |
d2aea775 | 128 | |
6debd840 AF |
129 | RISC-V firmware not booted by default (removed in 5.1) |
130 | '''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
131 | ||
132 | QEMU 5.1 changes the default behaviour from ``-bios none`` to ``-bios default`` | |
133 | for the RISC-V ``virt`` machine and ``sifive_u`` machine. | |
36585e2b | 134 | |
2c5060cd TH |
135 | QEMU Machine Protocol (QMP) commands |
136 | ------------------------------------ | |
137 | ||
138 | ``block-dirty-bitmap-add`` "autoload" parameter (removed in 4.2.0) | |
139 | '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
140 | ||
141 | The "autoload" parameter has been ignored since 2.12.0. All bitmaps | |
142 | are automatically loaded from qcow2 images. | |
143 | ||
144 | ``cpu-add`` (removed in 5.2) | |
145 | '''''''''''''''''''''''''''' | |
146 | ||
147 | Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``. See | |
148 | documentation of ``query-hotpluggable-cpus`` for additional details. | |
149 | ||
0afec757 PB |
150 | ``change`` (removed in 6.0) |
151 | ''''''''''''''''''''''''''' | |
152 | ||
153 | Use ``blockdev-change-medium`` or ``change-vnc-password`` instead. | |
154 | ||
8becb360 DB |
155 | ``query-events`` (removed in 6.0) |
156 | ''''''''''''''''''''''''''''''''' | |
157 | ||
158 | The ``query-events`` command has been superseded by the more powerful | |
159 | and accurate ``query-qmp-schema`` command. | |
160 | ||
cbde7be9 DB |
161 | ``migrate_set_cache_size`` and ``query-migrate-cache-size`` (removed in 6.0) |
162 | '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
163 | ||
164 | Use ``migrate_set_parameter`` and ``info migrate_parameters`` instead. | |
165 | ||
166 | ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0) | |
167 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
168 | ||
169 | Use ``migrate_set_parameter`` instead. | |
170 | ||
8af54b91 DB |
171 | ``query-cpus`` (removed in 6.0) |
172 | ''''''''''''''''''''''''''''''' | |
173 | ||
174 | The ``query-cpus`` command is replaced by the ``query-cpus-fast`` command. | |
175 | ||
445a5b40 DB |
176 | ``query-cpus-fast`` ``arch`` output member (removed in 6.0) |
177 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
178 | ||
179 | The ``arch`` output member of the ``query-cpus-fast`` command is | |
180 | replaced by the ``target`` output member. | |
181 | ||
24e13a4d DB |
182 | chardev client socket with ``wait`` option (removed in 6.0) |
183 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
184 | ||
185 | Character devices creating sockets in client mode should not specify | |
186 | the 'wait' field, which is only applicable to sockets in server mode | |
187 | ||
ad1324e0 DB |
188 | ``query-named-block-nodes`` result ``encryption_key_missing`` (removed in 6.0) |
189 | '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
190 | ||
191 | Removed with no replacement. | |
192 | ||
193 | ``query-block`` result ``inserted.encryption_key_missing`` (removed in 6.0) | |
194 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
195 | ||
196 | Removed with no replacement. | |
197 | ||
81cbfd50 DB |
198 | ``query-named-block-nodes`` and ``query-block`` result dirty-bitmaps[i].status (removed in 6.0) |
199 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
200 | ||
201 | The ``status`` field of the ``BlockDirtyInfo`` structure, returned by | |
202 | these commands is removed. Two new boolean fields, ``recording`` and | |
203 | ``busy`` effectively replace it. | |
204 | ||
e67d8e29 DB |
205 | ``query-block`` result field ``dirty-bitmaps`` (removed in 6.0) |
206 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
207 | ||
208 | The ``dirty-bitmaps`` field of the ``BlockInfo`` structure, returned by | |
209 | the query-block command is itself now removed. The ``dirty-bitmaps`` | |
210 | field of the ``BlockDeviceInfo`` struct should be used instead, which is the | |
211 | type of the ``inserted`` field in query-block replies, as well as the | |
212 | type of array items in query-named-block-nodes. | |
213 | ||
50243407 KW |
214 | ``object-add`` option ``props`` (removed in 6.0) |
215 | '''''''''''''''''''''''''''''''''''''''''''''''' | |
216 | ||
217 | Specify the properties for the object as top-level arguments instead. | |
218 | ||
2c5060cd TH |
219 | Human Monitor Protocol (HMP) commands |
220 | ------------------------------------- | |
221 | ||
222 | The ``hub_id`` parameter of ``hostfwd_add`` / ``hostfwd_remove`` (removed in 5.0) | |
223 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
224 | ||
225 | The ``[hub_id name]`` parameter tuple of the 'hostfwd_add' and | |
226 | 'hostfwd_remove' HMP commands has been replaced by ``netdev_id``. | |
227 | ||
228 | ``cpu-add`` (removed in 5.2) | |
229 | '''''''''''''''''''''''''''' | |
230 | ||
231 | Use ``device_add`` for hotplugging vCPUs instead of ``cpu-add``. See | |
232 | documentation of ``query-hotpluggable-cpus`` for additional details. | |
233 | ||
cfb5387a PB |
234 | ``change vnc TARGET`` (removed in 6.0) |
235 | '''''''''''''''''''''''''''''''''''''' | |
236 | ||
237 | No replacement. The ``change vnc password`` and ``change DEVICE MEDIUM`` | |
238 | commands are not affected. | |
239 | ||
5994dcb8 DB |
240 | ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, ``acl_remove`` (removed in 6.0) |
241 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
242 | ||
243 | The ``acl_show``, ``acl_reset``, ``acl_policy``, ``acl_add``, and | |
244 | ``acl_remove`` commands were removed with no replacement. Authorization | |
245 | for VNC should be performed using the pluggable QAuthZ objects. | |
246 | ||
cbde7be9 DB |
247 | ``migrate-set-cache-size`` and ``info migrate-cache-size`` (removed in 6.0) |
248 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
249 | ||
250 | Use ``migrate-set-parameters`` and ``info migrate-parameters`` instead. | |
251 | ||
252 | ``migrate_set_downtime`` and ``migrate_set_speed`` (removed in 6.0) | |
253 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
254 | ||
255 | Use ``migrate-set-parameters`` instead. | |
256 | ||
ca24b0b9 BL |
257 | ``info cpustats`` (removed in 6.1) |
258 | '''''''''''''''''''''''''''''''''' | |
259 | ||
260 | This command didn't produce any output already. Removed with no replacement. | |
261 | ||
2c5060cd TH |
262 | Guest Emulator ISAs |
263 | ------------------- | |
264 | ||
265 | RISC-V ISA privilege specification version 1.09.1 (removed in 5.1) | |
266 | '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
267 | ||
268 | The RISC-V ISA privilege specification version 1.09.1 has been removed. | |
269 | QEMU supports both the newer version 1.10.0 and the ratified version 1.11.0, these | |
270 | should be used instead of the 1.09.1 version. | |
271 | ||
272 | System emulator CPUS | |
273 | -------------------- | |
274 | ||
275 | KVM guest support on 32-bit Arm hosts (removed in 5.2) | |
276 | '''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
277 | ||
278 | The Linux kernel has dropped support for allowing 32-bit Arm systems | |
279 | to host KVM guests as of the 5.7 kernel. Accordingly, QEMU is deprecating | |
280 | its support for this configuration and will remove it in a future version. | |
281 | Running 32-bit guests on a 64-bit Arm host remains supported. | |
282 | ||
283 | RISC-V ISA Specific CPUs (removed in 5.1) | |
284 | ''''''''''''''''''''''''''''''''''''''''' | |
285 | ||
286 | The RISC-V cpus with the ISA version in the CPU name have been removed. The | |
287 | four CPUs are: ``rv32gcsu-v1.9.1``, ``rv32gcsu-v1.10.0``, ``rv64gcsu-v1.9.1`` and | |
288 | ``rv64gcsu-v1.10.0``. Instead the version can be specified via the CPU ``priv_spec`` | |
289 | option when using the ``rv32`` or ``rv64`` CPUs. | |
290 | ||
291 | RISC-V no MMU CPUs (removed in 5.1) | |
292 | ''''''''''''''''''''''''''''''''''' | |
293 | ||
294 | The RISC-V no MMU cpus have been removed. The two CPUs: ``rv32imacu-nommu`` and | |
295 | ``rv64imacu-nommu`` can no longer be used. Instead the MMU status can be specified | |
296 | via the CPU ``mmu`` option when using the ``rv32`` or ``rv64`` CPUs. | |
297 | ||
a058b895 GK |
298 | ``compat`` property of server class POWER CPUs (removed in 6.0) |
299 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
300 | ||
301 | The ``max-cpu-compat`` property of the ``pseries`` machine type should be used | |
302 | instead. | |
303 | ||
875bb7e3 TH |
304 | ``moxie`` CPU (removed in 6.1) |
305 | '''''''''''''''''''''''''''''' | |
306 | ||
307 | Nobody was using this CPU emulation in QEMU, and there were no test images | |
308 | available to make sure that the code is still working, so it has been removed | |
309 | without replacement. | |
310 | ||
9d49bcf6 MA |
311 | ``lm32`` CPUs (removed in 6.1.0) |
312 | '''''''''''''''''''''''''''''''' | |
313 | ||
314 | The only public user of this architecture was the milkymist project, | |
315 | which has been dead for years; there was never an upstream Linux | |
316 | port. Removed without replacement. | |
317 | ||
43692239 MA |
318 | ``unicore32`` CPUs (since 6.1.0) |
319 | '''''''''''''''''''''''''''''''' | |
320 | ||
321 | Support for this CPU was removed from the upstream Linux kernel, and | |
322 | there is no available upstream toolchain to build binaries for it. | |
323 | Removed without replacement. | |
324 | ||
2c5060cd TH |
325 | System emulator machines |
326 | ------------------------ | |
327 | ||
328 | ``spike_v1.9.1`` and ``spike_v1.10`` (removed in 5.1) | |
329 | ''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
330 | ||
331 | The version specific Spike machines have been removed in favour of the | |
332 | generic ``spike`` machine. If you need to specify an older version of the RISC-V | |
333 | spec you can use the ``-cpu rv64gcsu,priv_spec=v1.10.0`` command line argument. | |
334 | ||
335 | mips ``r4k`` platform (removed in 5.2) | |
336 | '''''''''''''''''''''''''''''''''''''' | |
337 | ||
338 | This machine type was very old and unmaintained. Users should use the ``malta`` | |
339 | machine type instead. | |
340 | ||
cd669e20 PMD |
341 | mips ``fulong2e`` machine alias (removed in 6.0) |
342 | '''''''''''''''''''''''''''''''''''''''''''''''' | |
343 | ||
344 | This machine has been renamed ``fuloong2e``. | |
345 | ||
f862ddbb TH |
346 | ``pc-1.0``, ``pc-1.1``, ``pc-1.2`` and ``pc-1.3`` (removed in 6.0) |
347 | '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
348 | ||
349 | These machine types were very old and likely could not be used for live | |
350 | migration from old QEMU versions anymore. Use a newer machine type instead. | |
351 | ||
2cc1a901 TH |
352 | |
353 | linux-user mode CPUs | |
354 | -------------------- | |
355 | ||
356 | ``tilegx`` CPUs (removed in 6.0) | |
357 | '''''''''''''''''''''''''''''''' | |
358 | ||
359 | The ``tilegx`` guest CPU support has been removed without replacement. It was | |
360 | only implemented in linux-user mode, but support for this CPU was removed from | |
361 | the upstream Linux kernel in 2018, and it has also been dropped from glibc, so | |
362 | there is no new Linux development taking place with this architecture. For | |
363 | running the old binaries, you can use older versions of QEMU. | |
364 | ||
b5010183 DB |
365 | System emulator devices |
366 | ----------------------- | |
367 | ||
368 | ``ide-drive`` (removed in 6.0) | |
369 | '''''''''''''''''''''''''''''' | |
370 | ||
371 | The 'ide-drive' device has been removed. Users should use 'ide-hd' or | |
372 | 'ide-cd' as appropriate to get an IDE hard disk or CD-ROM as needed. | |
2cc1a901 | 373 | |
879be3af DB |
374 | ``scsi-disk`` (removed in 6.0) |
375 | '''''''''''''''''''''''''''''' | |
376 | ||
377 | The 'scsi-disk' device has been removed. Users should use 'scsi-hd' or | |
378 | 'scsi-cd' as appropriate to get a SCSI hard disk or CD-ROM as needed. | |
379 | ||
2c5060cd TH |
380 | Related binaries |
381 | ---------------- | |
382 | ||
383 | ``qemu-nbd --partition`` (removed in 5.0) | |
384 | ''''''''''''''''''''''''''''''''''''''''' | |
385 | ||
386 | The ``qemu-nbd --partition $digit`` code (also spelled ``-P``) | |
387 | could only handle MBR partitions, and never correctly handled logical | |
388 | partitions beyond partition 5. Exporting a partition can still be | |
389 | done by utilizing the ``--image-opts`` option with a raw blockdev | |
390 | using the ``offset`` and ``size`` parameters layered on top of | |
391 | any other existing blockdev. For example, if partition 1 is 100MiB | |
392 | long starting at 1MiB, the old command:: | |
393 | ||
394 | qemu-nbd -t -P 1 -f qcow2 file.qcow2 | |
395 | ||
396 | can be rewritten as:: | |
397 | ||
398 | qemu-nbd -t --image-opts driver=raw,offset=1M,size=100M,file.driver=qcow2,file.file.driver=file,file.file.filename=file.qcow2 | |
399 | ||
400 | ``qemu-img convert -n -o`` (removed in 5.1) | |
401 | ''''''''''''''''''''''''''''''''''''''''''' | |
402 | ||
403 | All options specified in ``-o`` are image creation options, so | |
404 | they are now rejected when used with ``-n`` to skip image creation. | |
405 | ||
406 | ||
407 | ``qemu-img create -b bad file $size`` (removed in 5.1) | |
408 | '''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
409 | ||
410 | When creating an image with a backing file that could not be opened, | |
411 | ``qemu-img create`` used to issue a warning about the failure but | |
412 | proceed with the image creation if an explicit size was provided. | |
413 | However, as the ``-u`` option exists for this purpose, it is safer to | |
414 | enforce that any failure to open the backing image (including if the | |
415 | backing file is missing or an incorrect format was specified) is an | |
416 | error when ``-u`` is not used. | |
417 | ||
418 | Command line options | |
419 | -------------------- | |
420 | ||
421 | ``-smp`` (invalid topologies) (removed 5.2) | |
422 | ''''''''''''''''''''''''''''''''''''''''''' | |
423 | ||
424 | CPU topology properties should describe whole machine topology including | |
425 | possible CPUs. | |
426 | ||
427 | However, historically it was possible to start QEMU with an incorrect topology | |
428 | where *n* <= *sockets* * *cores* * *threads* < *maxcpus*, | |
429 | which could lead to an incorrect topology enumeration by the guest. | |
430 | Support for invalid topologies is removed, the user must ensure | |
431 | topologies described with -smp include all possible cpus, i.e. | |
432 | *sockets* * *cores* * *threads* = *maxcpus*. | |
433 | ||
434 | ``-numa`` node (without memory specified) (removed 5.2) | |
435 | ''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
436 | ||
437 | Splitting RAM by default between NUMA nodes had the same issues as ``mem`` | |
438 | parameter with the difference that the role of the user plays QEMU using | |
439 | implicit generic or board specific splitting rule. | |
440 | Use ``memdev`` with *memory-backend-ram* backend or ``mem`` (if | |
441 | it's supported by used machine type) to define mapping explicitly instead. | |
442 | Users of existing VMs, wishing to preserve the same RAM distribution, should | |
443 | configure it explicitly using ``-numa node,memdev`` options. Current RAM | |
444 | distribution can be retrieved using HMP command ``info numa`` and if separate | |
445 | memory devices (pc|nv-dimm) are present use ``info memory-device`` and subtract | |
446 | device memory from output of ``info numa``. | |
447 | ||
448 | ``-numa node,mem=``\ *size* (removed in 5.1) | |
449 | '''''''''''''''''''''''''''''''''''''''''''' | |
450 | ||
451 | The parameter ``mem`` of ``-numa node`` was used to assign a part of | |
452 | guest RAM to a NUMA node. But when using it, it's impossible to manage a specified | |
453 | RAM chunk on the host side (like bind it to a host node, setting bind policy, ...), | |
454 | so the guest ends up with the fake NUMA configuration with suboptiomal performance. | |
455 | However since 2014 there is an alternative way to assign RAM to a NUMA node | |
456 | using parameter ``memdev``, which does the same as ``mem`` and adds | |
457 | means to actually manage node RAM on the host side. Use parameter ``memdev`` | |
458 | with *memory-backend-ram* backend as replacement for parameter ``mem`` | |
459 | to achieve the same fake NUMA effect or a properly configured | |
460 | *memory-backend-file* backend to actually benefit from NUMA configuration. | |
461 | New machine versions (since 5.1) will not accept the option but it will still | |
462 | work with old machine types. User can check the QAPI schema to see if the legacy | |
463 | option is supported by looking at MachineInfo::numa-mem-supported property. | |
464 | ||
465 | ``-mem-path`` fallback to RAM (removed in 5.0) | |
466 | '''''''''''''''''''''''''''''''''''''''''''''' | |
467 | ||
468 | If guest RAM allocation from file pointed by ``mem-path`` failed, | |
469 | QEMU was falling back to allocating from RAM, which might have resulted | |
470 | in unpredictable behavior since the backing file specified by the user | |
471 | as ignored. Currently, users are responsible for making sure the backing storage | |
472 | specified with ``-mem-path`` can actually provide the guest RAM configured with | |
473 | ``-m`` and QEMU fails to start up if RAM allocation is unsuccessful. | |
474 | ||
475 | ``-smp`` (invalid topologies) (removed 5.2) | |
476 | ''''''''''''''''''''''''''''''''''''''''''' | |
477 | ||
478 | CPU topology properties should describe whole machine topology including | |
479 | possible CPUs. | |
480 | ||
481 | However, historically it was possible to start QEMU with an incorrect topology | |
482 | where *n* <= *sockets* * *cores* * *threads* < *maxcpus*, | |
483 | which could lead to an incorrect topology enumeration by the guest. | |
484 | Support for invalid topologies is removed, the user must ensure | |
485 | topologies described with -smp include all possible cpus, i.e. | |
486 | *sockets* * *cores* * *threads* = *maxcpus*. | |
487 | ||
488 | ``-machine enforce-config-section=on|off`` (removed 5.2) | |
489 | '''''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
490 | ||
491 | The ``enforce-config-section`` property was replaced by the | |
492 | ``-global migration.send-configuration={on|off}`` option. | |
493 | ||
5a385bf5 EB |
494 | qemu-img amend to adjust backing file (removed in 6.1) |
495 | '''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
496 | ||
497 | The use of ``qemu-img amend`` to modify the name or format of a qcow2 | |
498 | backing image was never fully documented or tested, and interferes | |
499 | with other amend operations that need access to the original backing | |
500 | image (such as deciding whether a v3 zero cluster may be left | |
501 | unallocated when converting to a v2 image). Any changes to the | |
502 | backing chain should be performed with ``qemu-img rebase -u`` either | |
503 | before or after the remaining changes being performed by amend, as | |
504 | appropriate. | |
505 | ||
497a30db EB |
506 | qemu-img backing file without format (removed in 6.1) |
507 | ''''''''''''''''''''''''''''''''''''''''''''''''''''' | |
508 | ||
509 | The use of ``qemu-img create``, ``qemu-img rebase``, or ``qemu-img | |
510 | convert`` to create or modify an image that depends on a backing file | |
511 | now requires that an explicit backing format be provided. This is | |
512 | for safety: if QEMU probes a different format than what you thought, | |
513 | the data presented to the guest will be corrupt; similarly, presenting | |
514 | a raw image to a guest allows a potential security exploit if a future | |
515 | probe sees a non-raw image based on guest writes. | |
516 | ||
517 | To avoid creating unsafe backing chains, you must pass ``-o | |
518 | backing_fmt=`` (or the shorthand ``-F`` during create) to specify the | |
519 | intended backing format. You may use ``qemu-img rebase -u`` to | |
520 | retroactively add a backing format to an existing image. However, be | |
521 | aware that there are already potential security risks to blindly using | |
522 | ``qemu-img info`` to probe the format of an untrusted backing image, | |
523 | when deciding what format to add into an existing image. | |
524 | ||
2c5060cd TH |
525 | Block devices |
526 | ------------- | |
527 | ||
528 | VXHS backend (removed in 5.1) | |
529 | ''''''''''''''''''''''''''''' | |
530 | ||
531 | The VXHS code did not compile since v2.12.0. It was removed in 5.1. | |
09ec8517 MA |
532 | |
533 | ``sheepdog`` driver (removed in 6.0) | |
534 | '''''''''''''''''''''''''''''''''''' | |
535 | ||
536 | The corresponding upstream server project is no longer maintained. | |
537 | Users are recommended to switch to an alternative distributed block | |
538 | device driver such as RBD. |