target/arm: Implement tailchaining for M profile cores
[qemu/ar7.git] / qemu-options.hx
blobb1bf0f485f9b609ba13ffd888475abe9efc20501
1 HXCOMM Use DEFHEADING() to define headings in both help text and texi
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
4 HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
5 HXCOMM construct option structures, enums and help message for specified
6 HXCOMM architectures.
7 HXCOMM HXCOMM can be used for comments, discarded from both texi and C
9 DEFHEADING(Standard options:)
10 STEXI
11 @table @option
12 ETEXI
14 DEF("help", 0, QEMU_OPTION_h,
15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL)
16 STEXI
17 @item -h
18 @findex -h
19 Display help and exit
20 ETEXI
22 DEF("version", 0, QEMU_OPTION_version,
23 "-version display version information and exit\n", QEMU_ARCH_ALL)
24 STEXI
25 @item -version
26 @findex -version
27 Display version information and exit
28 ETEXI
30 DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
31 "-machine [type=]name[,prop[=value][,...]]\n"
32 " selects emulated machine ('-machine help' for list)\n"
33 " property accel=accel1[:accel2[:...]] selects accelerator\n"
34 " supported accelerators are kvm, xen, hax, hvf, whpx or tcg (default: tcg)\n"
35 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n"
36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n"
37 " kvm_shadow_mem=size of KVM shadow MMU in bytes\n"
38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
39 " mem-merge=on|off controls memory merge support (default: on)\n"
40 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
41 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
44 " nvdimm=on|off controls NVDIMM support (default=off)\n"
45 " enforce-config-section=on|off enforce configuration section migration (default=off)\n"
46 " s390-squash-mcss=on|off (deprecated) controls support for squashing into default css (default=off)\n"
47 " memory-encryption=@var{} memory encryption object to use (default=none)\n",
48 QEMU_ARCH_ALL)
49 STEXI
50 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
51 @findex -machine
52 Select the emulated machine by @var{name}. Use @code{-machine help} to list
53 available machines.
55 For architectures which aim to support live migration compatibility
56 across releases, each release will introduce a new versioned machine
57 type. For example, the 2.8.0 release introduced machine types
58 ``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures.
60 To allow live migration of guests from QEMU version 2.8.0, to QEMU
61 version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8''
62 and ``pc-q35-2.8'' machines too. To allow users live migrating VMs
63 to skip multiple intermediate releases when upgrading, new releases
64 of QEMU will support machine types from many previous versions.
66 Supported machine properties are:
67 @table @option
68 @item accel=@var{accels1}[:@var{accels2}[:...]]
69 This is used to enable an accelerator. Depending on the target architecture,
70 kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is
71 more than one accelerator specified, the next one is used if the previous one
72 fails to initialize.
73 @item kernel_irqchip=on|off
74 Controls in-kernel irqchip support for the chosen accelerator when available.
75 @item gfx_passthru=on|off
76 Enables IGD GFX passthrough support for the chosen machine when available.
77 @item vmport=on|off|auto
78 Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the
79 value based on accel. For accel=xen the default is off otherwise the default
80 is on.
81 @item kvm_shadow_mem=size
82 Defines the size of the KVM shadow MMU.
83 @item dump-guest-core=on|off
84 Include guest memory in a core dump. The default is on.
85 @item mem-merge=on|off
86 Enables or disables memory merge support. This feature, when supported by
87 the host, de-duplicates identical memory pages among VMs instances
88 (enabled by default).
89 @item aes-key-wrap=on|off
90 Enables or disables AES key wrapping support on s390-ccw hosts. This feature
91 controls whether AES wrapping keys will be created to allow
92 execution of AES cryptographic functions. The default is on.
93 @item dea-key-wrap=on|off
94 Enables or disables DEA key wrapping support on s390-ccw hosts. This feature
95 controls whether DEA wrapping keys will be created to allow
96 execution of DEA cryptographic functions. The default is on.
97 @item nvdimm=on|off
98 Enables or disables NVDIMM support. The default is off.
99 @item s390-squash-mcss=on|off
100 Enables or disables squashing subchannels into the default css.
101 The default is off.
102 NOTE: This property is deprecated and will be removed in future releases.
103 The ``s390-squash-mcss=on`` property has been obsoleted by allowing the
104 cssid to be chosen freely. Instead of squashing subchannels into the
105 default channel subsystem image for guests that do not support multiple
106 channel subsystems, all devices can be put into the default channel
107 subsystem image.
108 @item enforce-config-section=on|off
109 If @option{enforce-config-section} is set to @var{on}, force migration
110 code to send configuration section even if the machine-type sets the
111 @option{migration.send-configuration} property to @var{off}.
112 NOTE: this parameter is deprecated. Please use @option{-global}
113 @option{migration.send-configuration}=@var{on|off} instead.
114 @item memory-encryption=@var{}
115 Memory encryption object to use. The default is none.
116 @end table
117 ETEXI
119 HXCOMM Deprecated by -machine
120 DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
122 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
123 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
124 STEXI
125 @item -cpu @var{model}
126 @findex -cpu
127 Select CPU model (@code{-cpu help} for list and additional feature selection)
128 ETEXI
130 DEF("accel", HAS_ARG, QEMU_OPTION_accel,
131 "-accel [accel=]accelerator[,thread=single|multi]\n"
132 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n"
133 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL)
134 STEXI
135 @item -accel @var{name}[,prop=@var{value}[,...]]
136 @findex -accel
137 This is used to enable an accelerator. Depending on the target architecture,
138 kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is
139 more than one accelerator specified, the next one is used if the previous one
140 fails to initialize.
141 @table @option
142 @item thread=single|multi
143 Controls number of TCG threads. When the TCG is multi-threaded there will be one
144 thread per vCPU therefor taking advantage of additional host cores. The default
145 is to enable multi-threading where both the back-end and front-ends support it and
146 no incompatible TCG features have been enabled (e.g. icount/replay).
147 @end table
148 ETEXI
150 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
151 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
152 " set the number of CPUs to 'n' [default=1]\n"
153 " maxcpus= maximum number of total cpus, including\n"
154 " offline CPUs for hotplug, etc\n"
155 " cores= number of CPU cores on one socket\n"
156 " threads= number of threads on one CPU core\n"
157 " sockets= number of discrete sockets in the system\n",
158 QEMU_ARCH_ALL)
159 STEXI
160 @item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
161 @findex -smp
162 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
163 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
164 to 4.
165 For the PC target, the number of @var{cores} per socket, the number
166 of @var{threads} per cores and the total number of @var{sockets} can be
167 specified. Missing values will be computed. If any on the three values is
168 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
169 specifies the maximum number of hotpluggable CPUs.
170 ETEXI
172 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
173 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
174 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
175 "-numa dist,src=source,dst=destination,val=distance\n"
176 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n",
177 QEMU_ARCH_ALL)
178 STEXI
179 @item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
180 @itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
181 @itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance}
182 @itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}]
183 @findex -numa
184 Define a NUMA node and assign RAM and VCPUs to it.
185 Set the NUMA distance from a source node to a destination node.
187 Legacy VCPU assignment uses @samp{cpus} option where
188 @var{firstcpu} and @var{lastcpu} are CPU indexes. Each
189 @samp{cpus} option represent a contiguous range of CPU indexes
190 (or a single VCPU if @var{lastcpu} is omitted). A non-contiguous
191 set of VCPUs can be represented by providing multiple @samp{cpus}
192 options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically
193 split between them.
195 For example, the following option assigns VCPUs 0, 1, 2 and 5 to
196 a NUMA node:
197 @example
198 -numa node,cpus=0-2,cpus=5
199 @end example
201 @samp{cpu} option is a new alternative to @samp{cpus} option
202 which uses @samp{socket-id|core-id|thread-id} properties to assign
203 CPU objects to a @var{node} using topology layout properties of CPU.
204 The set of properties is machine specific, and depends on used
205 machine type/@samp{smp} options. It could be queried with
206 @samp{hotpluggable-cpus} monitor command.
207 @samp{node-id} property specifies @var{node} to which CPU object
208 will be assigned, it's required for @var{node} to be declared
209 with @samp{node} option before it's used with @samp{cpu} option.
211 For example:
212 @example
213 -M pc \
214 -smp 1,sockets=2,maxcpus=2 \
215 -numa node,nodeid=0 -numa node,nodeid=1 \
216 -numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1
217 @end example
219 @samp{mem} assigns a given RAM amount to a node. @samp{memdev}
220 assigns RAM from a given memory backend device to a node. If
221 @samp{mem} and @samp{memdev} are omitted in all nodes, RAM is
222 split equally between them.
224 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore,
225 if one node uses @samp{memdev}, all of them have to use it.
227 @var{source} and @var{destination} are NUMA node IDs.
228 @var{distance} is the NUMA distance from @var{source} to @var{destination}.
229 The distance from a node to itself is always 10. If any pair of nodes is
230 given a distance, then all pairs must be given distances. Although, when
231 distances are only given in one direction for each pair of nodes, then
232 the distances in the opposite directions are assumed to be the same. If,
233 however, an asymmetrical pair of distances is given for even one node
234 pair, then all node pairs must be provided distance values for both
235 directions, even when they are symmetrical. When a node is unreachable
236 from another node, set the pair's distance to 255.
238 Note that the -@option{numa} option doesn't allocate any of the
239 specified resources, it just assigns existing resources to NUMA
240 nodes. This means that one still has to use the @option{-m},
241 @option{-smp} options to allocate RAM and VCPUs respectively.
243 ETEXI
245 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
246 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
247 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
248 STEXI
249 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
250 @findex -add-fd
252 Add a file descriptor to an fd set. Valid options are:
254 @table @option
255 @item fd=@var{fd}
256 This option defines the file descriptor of which a duplicate is added to fd set.
257 The file descriptor cannot be stdin, stdout, or stderr.
258 @item set=@var{set}
259 This option defines the ID of the fd set to add the file descriptor to.
260 @item opaque=@var{opaque}
261 This option defines a free-form string that can be used to describe @var{fd}.
262 @end table
264 You can open an image using pre-opened file descriptors from an fd set:
265 @example
266 qemu-system-i386
267 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
268 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
269 -drive file=/dev/fdset/2,index=0,media=disk
270 @end example
271 ETEXI
273 DEF("set", HAS_ARG, QEMU_OPTION_set,
274 "-set group.id.arg=value\n"
275 " set <arg> parameter for item <id> of type <group>\n"
276 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
277 STEXI
278 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
279 @findex -set
280 Set parameter @var{arg} for item @var{id} of type @var{group}
281 ETEXI
283 DEF("global", HAS_ARG, QEMU_OPTION_global,
284 "-global driver.property=value\n"
285 "-global driver=driver,property=property,value=value\n"
286 " set a global default for a driver property\n",
287 QEMU_ARCH_ALL)
288 STEXI
289 @item -global @var{driver}.@var{prop}=@var{value}
290 @itemx -global driver=@var{driver},property=@var{property},value=@var{value}
291 @findex -global
292 Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
294 @example
295 qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img
296 @end example
298 In particular, you can use this to set driver properties for devices which are
299 created automatically by the machine model. To create a device which is not
300 created automatically and set properties on it, use -@option{device}.
302 -global @var{driver}.@var{prop}=@var{value} is shorthand for -global
303 driver=@var{driver},property=@var{prop},value=@var{value}. The
304 longhand syntax works even when @var{driver} contains a dot.
305 ETEXI
307 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
308 "-boot [order=drives][,once=drives][,menu=on|off]\n"
309 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
310 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
311 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
312 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
313 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
314 QEMU_ARCH_ALL)
315 STEXI
316 @item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}][,reboot-timeout=@var{rb_timeout}][,strict=on|off]
317 @findex -boot
318 Specify boot order @var{drives} as a string of drive letters. Valid
319 drive letters depend on the target architecture. The x86 PC uses: a, b
320 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
321 from network adapter 1-4), hard disk boot is the default. To apply a
322 particular boot order only on the first startup, specify it via
323 @option{once}. Note that the @option{order} or @option{once} parameter
324 should not be used together with the @option{bootindex} property of
325 devices, since the firmware implementations normally do not support both
326 at the same time.
328 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
329 as firmware/BIOS supports them. The default is non-interactive boot.
331 A splash picture could be passed to bios, enabling user to show it as logo,
332 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
333 supports them. Currently Seabios for X86 system support it.
334 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
335 format(true color). The resolution should be supported by the SVGA mode, so
336 the recommended is 320x240, 640x480, 800x640.
338 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
339 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
340 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
341 system support it.
343 Do strict boot via @option{strict=on} as far as firmware/BIOS
344 supports it. This only effects when boot priority is changed by
345 bootindex options. The default is non-strict boot.
347 @example
348 # try to boot from network first, then from hard disk
349 qemu-system-i386 -boot order=nc
350 # boot from CD-ROM first, switch back to default order after reboot
351 qemu-system-i386 -boot once=d
352 # boot with a splash picture for 5 seconds.
353 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
354 @end example
356 Note: The legacy format '-boot @var{drives}' is still supported but its
357 use is discouraged as it may be removed from future versions.
358 ETEXI
360 DEF("m", HAS_ARG, QEMU_OPTION_m,
361 "-m [size=]megs[,slots=n,maxmem=size]\n"
362 " configure guest RAM\n"
363 " size: initial amount of guest memory\n"
364 " slots: number of hotplug slots (default: none)\n"
365 " maxmem: maximum amount of guest memory (default: none)\n"
366 "NOTE: Some architectures might enforce a specific granularity\n",
367 QEMU_ARCH_ALL)
368 STEXI
369 @item -m [size=]@var{megs}[,slots=n,maxmem=size]
370 @findex -m
371 Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
372 Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
373 megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
374 could be used to set amount of hotpluggable memory slots and maximum amount of
375 memory. Note that @var{maxmem} must be aligned to the page size.
377 For example, the following command-line sets the guest startup RAM size to
378 1GB, creates 3 slots to hotplug additional memory and sets the maximum
379 memory the guest can reach to 4GB:
381 @example
382 qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
383 @end example
385 If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
386 be enabled and the guest startup RAM will never increase.
387 ETEXI
389 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
390 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
391 STEXI
392 @item -mem-path @var{path}
393 @findex -mem-path
394 Allocate guest RAM from a temporarily created file in @var{path}.
395 ETEXI
397 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
398 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
399 QEMU_ARCH_ALL)
400 STEXI
401 @item -mem-prealloc
402 @findex -mem-prealloc
403 Preallocate memory when using -mem-path.
404 ETEXI
406 DEF("k", HAS_ARG, QEMU_OPTION_k,
407 "-k language use keyboard layout (for example 'fr' for French)\n",
408 QEMU_ARCH_ALL)
409 STEXI
410 @item -k @var{language}
411 @findex -k
412 Use keyboard layout @var{language} (for example @code{fr} for
413 French). This option is only needed where it is not easy to get raw PC
414 keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
415 display). You don't normally need to use it on PC/Linux or PC/Windows
416 hosts.
418 The available layouts are:
419 @example
420 ar de-ch es fo fr-ca hu ja mk no pt-br sv
421 da en-gb et fr fr-ch is lt nl pl ru th
422 de en-us fi fr-be hr it lv nl-be pt sl tr
423 @end example
425 The default is @code{en-us}.
426 ETEXI
429 DEF("audio-help", 0, QEMU_OPTION_audio_help,
430 "-audio-help print list of audio drivers and their options\n",
431 QEMU_ARCH_ALL)
432 STEXI
433 @item -audio-help
434 @findex -audio-help
435 Will show the audio subsystem help: list of drivers, tunable
436 parameters.
437 ETEXI
439 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
440 "-soundhw c1,... enable audio support\n"
441 " and only specified sound cards (comma separated list)\n"
442 " use '-soundhw help' to get the list of supported cards\n"
443 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
444 STEXI
445 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
446 @findex -soundhw
447 Enable audio and selected sound hardware. Use 'help' to print all
448 available sound hardware.
450 @example
451 qemu-system-i386 -soundhw sb16,adlib disk.img
452 qemu-system-i386 -soundhw es1370 disk.img
453 qemu-system-i386 -soundhw ac97 disk.img
454 qemu-system-i386 -soundhw hda disk.img
455 qemu-system-i386 -soundhw all disk.img
456 qemu-system-i386 -soundhw help
457 @end example
459 Note that Linux's i810_audio OSS kernel (for AC97) module might
460 require manually specifying clocking.
462 @example
463 modprobe i810_audio clocking=48000
464 @end example
465 ETEXI
467 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
468 "-balloon virtio[,addr=str]\n"
469 " enable virtio balloon device (deprecated)\n", QEMU_ARCH_ALL)
470 STEXI
471 @item -balloon virtio[,addr=@var{addr}]
472 @findex -balloon
473 Enable virtio balloon device, optionally with PCI address @var{addr}. This
474 option is deprecated, use @option{-device virtio-balloon} instead.
475 ETEXI
477 DEF("device", HAS_ARG, QEMU_OPTION_device,
478 "-device driver[,prop[=value][,...]]\n"
479 " add device (based on driver)\n"
480 " prop=value,... sets driver properties\n"
481 " use '-device help' to print all possible drivers\n"
482 " use '-device driver,help' to print all possible properties\n",
483 QEMU_ARCH_ALL)
484 STEXI
485 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
486 @findex -device
487 Add device @var{driver}. @var{prop}=@var{value} sets driver
488 properties. Valid properties depend on the driver. To get help on
489 possible drivers and properties, use @code{-device help} and
490 @code{-device @var{driver},help}.
492 Some drivers are:
493 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}]
495 Add an IPMI BMC. This is a simulation of a hardware management
496 interface processor that normally sits on a system. It provides
497 a watchdog and the ability to reset and power control the system.
498 You need to connect this to an IPMI interface to make it useful
500 The IPMI slave address to use for the BMC. The default is 0x20.
501 This address is the BMC's address on the I2C network of management
502 controllers. If you don't know what this means, it is safe to ignore
505 @table @option
506 @item bmc=@var{id}
507 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
508 @item slave_addr=@var{val}
509 Define slave address to use for the BMC. The default is 0x20.
510 @item sdrfile=@var{file}
511 file containing raw Sensor Data Records (SDR) data. The default is none.
512 @item fruareasize=@var{val}
513 size of a Field Replaceable Unit (FRU) area. The default is 1024.
514 @item frudatafile=@var{file}
515 file containing raw Field Replaceable Unit (FRU) inventory data. The default is none.
516 @end table
518 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
520 Add a connection to an external IPMI BMC simulator. Instead of
521 locally emulating the BMC like the above item, instead connect
522 to an external entity that provides the IPMI services.
524 A connection is made to an external BMC simulator. If you do this, it
525 is strongly recommended that you use the "reconnect=" chardev option
526 to reconnect to the simulator if the connection is lost. Note that if
527 this is not used carefully, it can be a security issue, as the
528 interface has the ability to send resets, NMIs, and power off the VM.
529 It's best if QEMU makes a connection to an external simulator running
530 on a secure port on localhost, so neither the simulator nor QEMU is
531 exposed to any outside network.
533 See the "lanserv/README.vm" file in the OpenIPMI library for more
534 details on the external interface.
536 @item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
538 Add a KCS IPMI interafce on the ISA bus. This also adds a
539 corresponding ACPI and SMBIOS entries, if appropriate.
541 @table @option
542 @item bmc=@var{id}
543 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
544 @item ioport=@var{val}
545 Define the I/O address of the interface. The default is 0xca0 for KCS.
546 @item irq=@var{val}
547 Define the interrupt to use. The default is 5. To disable interrupts,
548 set this to 0.
549 @end table
551 @item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
553 Like the KCS interface, but defines a BT interface. The default port is
554 0xe4 and the default interrupt is 5.
556 ETEXI
558 DEF("name", HAS_ARG, QEMU_OPTION_name,
559 "-name string1[,process=string2][,debug-threads=on|off]\n"
560 " set the name of the guest\n"
561 " string1 sets the window title and string2 the process name (on Linux)\n"
562 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
563 " NOTE: The thread names are for debugging and not a stable API.\n",
564 QEMU_ARCH_ALL)
565 STEXI
566 @item -name @var{name}
567 @findex -name
568 Sets the @var{name} of the guest.
569 This name will be displayed in the SDL window caption.
570 The @var{name} will also be used for the VNC server.
571 Also optionally set the top visible process name in Linux.
572 Naming of individual threads can also be enabled on Linux to aid debugging.
573 ETEXI
575 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
576 "-uuid %08x-%04x-%04x-%04x-%012x\n"
577 " specify machine UUID\n", QEMU_ARCH_ALL)
578 STEXI
579 @item -uuid @var{uuid}
580 @findex -uuid
581 Set system UUID.
582 ETEXI
584 STEXI
585 @end table
586 ETEXI
587 DEFHEADING()
589 DEFHEADING(Block device options:)
590 STEXI
591 @table @option
592 ETEXI
594 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
595 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
596 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
597 STEXI
598 @item -fda @var{file}
599 @itemx -fdb @var{file}
600 @findex -fda
601 @findex -fdb
602 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
603 ETEXI
605 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
606 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
607 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
608 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
609 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
610 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
611 STEXI
612 @item -hda @var{file}
613 @itemx -hdb @var{file}
614 @itemx -hdc @var{file}
615 @itemx -hdd @var{file}
616 @findex -hda
617 @findex -hdb
618 @findex -hdc
619 @findex -hdd
620 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
621 ETEXI
623 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
624 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
625 QEMU_ARCH_ALL)
626 STEXI
627 @item -cdrom @var{file}
628 @findex -cdrom
629 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
630 @option{-cdrom} at the same time). You can use the host CD-ROM by
631 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
632 ETEXI
634 DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev,
635 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n"
636 " [,cache.direct=on|off][,cache.no-flush=on|off]\n"
637 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n"
638 " [,driver specific parameters...]\n"
639 " configure a block backend\n", QEMU_ARCH_ALL)
640 STEXI
641 @item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]]
642 @findex -blockdev
644 Define a new block driver node. Some of the options apply to all block drivers,
645 other options are only accepted for a specific block driver. See below for a
646 list of generic options and options for the most common block drivers.
648 Options that expect a reference to another node (e.g. @code{file}) can be
649 given in two ways. Either you specify the node name of an already existing node
650 (file=@var{node-name}), or you define a new node inline, adding options
651 for the referenced node after a dot (file.filename=@var{path},file.aio=native).
653 A block driver node created with @option{-blockdev} can be used for a guest
654 device by specifying its node name for the @code{drive} property in a
655 @option{-device} argument that defines a block device.
657 @table @option
658 @item Valid options for any block driver node:
660 @table @code
661 @item driver
662 Specifies the block driver to use for the given node.
663 @item node-name
664 This defines the name of the block driver node by which it will be referenced
665 later. The name must be unique, i.e. it must not match the name of a different
666 block driver node, or (if you use @option{-drive} as well) the ID of a drive.
668 If no node name is specified, it is automatically generated. The generated node
669 name is not intended to be predictable and changes between QEMU invocations.
670 For the top level, an explicit node name must be specified.
671 @item read-only
672 Open the node read-only. Guest write attempts will fail.
673 @item cache.direct
674 The host page cache can be avoided with @option{cache.direct=on}. This will
675 attempt to do disk IO directly to the guest's memory. QEMU may still perform an
676 internal copy of the data.
677 @item cache.no-flush
678 In case you don't care about data integrity over host failures, you can use
679 @option{cache.no-flush=on}. This option tells QEMU that it never needs to write
680 any data to the disk but can instead keep things in cache. If anything goes
681 wrong, like your host losing power, the disk storage getting disconnected
682 accidentally, etc. your image will most probably be rendered unusable.
683 @item discard=@var{discard}
684 @var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls
685 whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are
686 ignored or passed to the filesystem. Some machine types may not support
687 discard requests.
688 @item detect-zeroes=@var{detect-zeroes}
689 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
690 conversion of plain zero writes by the OS to driver specific optimized
691 zero write commands. You may even choose "unmap" if @var{discard} is set
692 to "unmap" to allow a zero write to be converted to an @code{unmap} operation.
693 @end table
695 @item Driver-specific options for @code{file}
697 This is the protocol-level block driver for accessing regular files.
699 @table @code
700 @item filename
701 The path to the image file in the local filesystem
702 @item aio
703 Specifies the AIO backend (threads/native, default: threads)
704 @item locking
705 Specifies whether the image file is protected with Linux OFD / POSIX locks. The
706 default is to use the Linux Open File Descriptor API if available, otherwise no
707 lock is applied. (auto/on/off, default: auto)
708 @end table
709 Example:
710 @example
711 -blockdev driver=file,node-name=disk,filename=disk.img
712 @end example
714 @item Driver-specific options for @code{raw}
716 This is the image format block driver for raw images. It is usually
717 stacked on top of a protocol level block driver such as @code{file}.
719 @table @code
720 @item file
721 Reference to or definition of the data source block driver node
722 (e.g. a @code{file} driver node)
723 @end table
724 Example 1:
725 @example
726 -blockdev driver=file,node-name=disk_file,filename=disk.img
727 -blockdev driver=raw,node-name=disk,file=disk_file
728 @end example
729 Example 2:
730 @example
731 -blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img
732 @end example
734 @item Driver-specific options for @code{qcow2}
736 This is the image format block driver for qcow2 images. It is usually
737 stacked on top of a protocol level block driver such as @code{file}.
739 @table @code
740 @item file
741 Reference to or definition of the data source block driver node
742 (e.g. a @code{file} driver node)
744 @item backing
745 Reference to or definition of the backing file block device (default is taken
746 from the image file). It is allowed to pass @code{null} here in order to disable
747 the default backing file.
749 @item lazy-refcounts
750 Whether to enable the lazy refcounts feature (on/off; default is taken from the
751 image file)
753 @item cache-size
754 The maximum total size of the L2 table and refcount block caches in bytes
755 (default: 1048576 bytes or 8 clusters, whichever is larger)
757 @item l2-cache-size
758 The maximum size of the L2 table cache in bytes
759 (default: 4/5 of the total cache size)
761 @item refcount-cache-size
762 The maximum size of the refcount block cache in bytes
763 (default: 1/5 of the total cache size)
765 @item cache-clean-interval
766 Clean unused entries in the L2 and refcount caches. The interval is in seconds.
767 The default value is 0 and it disables this feature.
769 @item pass-discard-request
770 Whether discard requests to the qcow2 device should be forwarded to the data
771 source (on/off; default: on if discard=unmap is specified, off otherwise)
773 @item pass-discard-snapshot
774 Whether discard requests for the data source should be issued when a snapshot
775 operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off;
776 default: on)
778 @item pass-discard-other
779 Whether discard requests for the data source should be issued on other
780 occasions where a cluster gets freed (on/off; default: off)
782 @item overlap-check
783 Which overlap checks to perform for writes to the image
784 (none/constant/cached/all; default: cached). For details or finer
785 granularity control refer to the QAPI documentation of @code{blockdev-add}.
786 @end table
788 Example 1:
789 @example
790 -blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
791 -blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216
792 @end example
793 Example 2:
794 @example
795 -blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2
796 @end example
798 @item Driver-specific options for other drivers
799 Please refer to the QAPI documentation of the @code{blockdev-add} QMP command.
801 @end table
803 ETEXI
805 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
806 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
807 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
808 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
809 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
810 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
811 " [,readonly=on|off][,copy-on-read=on|off]\n"
812 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
813 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
814 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
815 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
816 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
817 " [[,iops_size=is]]\n"
818 " [[,group=g]]\n"
819 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
820 STEXI
821 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
822 @findex -drive
824 Define a new drive. This includes creating a block driver node (the backend) as
825 well as a guest device, and is mostly a shortcut for defining the corresponding
826 @option{-blockdev} and @option{-device} options.
828 @option{-drive} accepts all options that are accepted by @option{-blockdev}. In
829 addition, it knows the following options:
831 @table @option
832 @item file=@var{file}
833 This option defines which disk image (@pxref{disk_images}) to use with
834 this drive. If the filename contains comma, you must double it
835 (for instance, "file=my,,file" to use file "my,file").
837 Special files such as iSCSI devices can be specified using protocol
838 specific URLs. See the section for "Device URL Syntax" for more information.
839 @item if=@var{interface}
840 This option defines on which type on interface the drive is connected.
841 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
842 @item bus=@var{bus},unit=@var{unit}
843 These options define where is connected the drive by defining the bus number and
844 the unit id.
845 @item index=@var{index}
846 This option defines where is connected the drive by using an index in the list
847 of available connectors of a given interface type.
848 @item media=@var{media}
849 This option defines the type of the media: disk or cdrom.
850 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
851 Force disk physical geometry and the optional BIOS translation (trans=none or
852 lba). These parameters are deprecated, use the corresponding parameters
853 of @code{-device} instead.
854 @item snapshot=@var{snapshot}
855 @var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
856 (see @option{-snapshot}).
857 @item cache=@var{cache}
858 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough"
859 and controls how the host cache is used to access block data. This is a
860 shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
861 options (as in @option{-blockdev}), and additionally @option{cache.writeback},
862 which provides a default for the @option{write-cache} option of block guest
863 devices (as in @option{-device}). The modes correspond to the following
864 settings:
866 @c Our texi2pod.pl script doesn't support @multitable, so fall back to using
867 @c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
868 @c and the HTML output.
869 @example
870 @ │ cache.writeback cache.direct cache.no-flush
871 ─────────────┼─────────────────────────────────────────────────
872 writeback │ on off off
873 none │ on on off
874 writethrough │ off off off
875 directsync │ off on off
876 unsafe │ on off on
877 @end example
879 The default mode is @option{cache=writeback}.
881 @item aio=@var{aio}
882 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
883 @item format=@var{format}
884 Specify which disk @var{format} will be used rather than detecting
885 the format. Can be used to specify format=raw to avoid interpreting
886 an untrusted format header.
887 @item serial=@var{serial}
888 This option specifies the serial number to assign to the device. This
889 parameter is deprecated, use the corresponding parameter of @code{-device}
890 instead.
891 @item addr=@var{addr}
892 Specify the controller's PCI address (if=virtio only). This parameter is
893 deprecated, use the corresponding parameter of @code{-device} instead.
894 @item werror=@var{action},rerror=@var{action}
895 Specify which @var{action} to take on write and read errors. Valid actions are:
896 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
897 "report" (report the error to the guest), "enospc" (pause QEMU only if the
898 host disk is full; report the error to the guest otherwise).
899 The default setting is @option{werror=enospc} and @option{rerror=report}.
900 @item copy-on-read=@var{copy-on-read}
901 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
902 file sectors into the image file.
903 @item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
904 Specify bandwidth throttling limits in bytes per second, either for all request
905 types or for reads or writes only. Small values can lead to timeouts or hangs
906 inside the guest. A safe minimum for disks is 2 MB/s.
907 @item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
908 Specify bursts in bytes per second, either for all request types or for reads
909 or writes only. Bursts allow the guest I/O to spike above the limit
910 temporarily.
911 @item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
912 Specify request rate limits in requests per second, either for all request
913 types or for reads or writes only.
914 @item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
915 Specify bursts in requests per second, either for all request types or for reads
916 or writes only. Bursts allow the guest I/O to spike above the limit
917 temporarily.
918 @item iops_size=@var{is}
919 Let every @var{is} bytes of a request count as a new request for iops
920 throttling purposes. Use this option to prevent guests from circumventing iops
921 limits by sending fewer but larger requests.
922 @item group=@var{g}
923 Join a throttling quota group with given name @var{g}. All drives that are
924 members of the same group are accounted for together. Use this option to
925 prevent guests from circumventing throttling limits by using many small disks
926 instead of a single larger disk.
927 @end table
929 By default, the @option{cache.writeback=on} mode is used. It will report data
930 writes as completed as soon as the data is present in the host page cache.
931 This is safe as long as your guest OS makes sure to correctly flush disk caches
932 where needed. If your guest OS does not handle volatile disk write caches
933 correctly and your host crashes or loses power, then the guest may experience
934 data corruption.
936 For such guests, you should consider using @option{cache.writeback=off}. This
937 means that the host page cache will be used to read and write data, but write
938 notification will be sent to the guest only after QEMU has made sure to flush
939 each write to the disk. Be aware that this has a major impact on performance.
941 When using the @option{-snapshot} option, unsafe caching is always used.
943 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
944 useful when the backing file is over a slow network. By default copy-on-read
945 is off.
947 Instead of @option{-cdrom} you can use:
948 @example
949 qemu-system-i386 -drive file=file,index=2,media=cdrom
950 @end example
952 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
953 use:
954 @example
955 qemu-system-i386 -drive file=file,index=0,media=disk
956 qemu-system-i386 -drive file=file,index=1,media=disk
957 qemu-system-i386 -drive file=file,index=2,media=disk
958 qemu-system-i386 -drive file=file,index=3,media=disk
959 @end example
961 You can open an image using pre-opened file descriptors from an fd set:
962 @example
963 qemu-system-i386
964 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
965 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
966 -drive file=/dev/fdset/2,index=0,media=disk
967 @end example
969 You can connect a CDROM to the slave of ide0:
970 @example
971 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
972 @end example
974 If you don't specify the "file=" argument, you define an empty drive:
975 @example
976 qemu-system-i386 -drive if=ide,index=1,media=cdrom
977 @end example
979 Instead of @option{-fda}, @option{-fdb}, you can use:
980 @example
981 qemu-system-i386 -drive file=file,index=0,if=floppy
982 qemu-system-i386 -drive file=file,index=1,if=floppy
983 @end example
985 By default, @var{interface} is "ide" and @var{index} is automatically
986 incremented:
987 @example
988 qemu-system-i386 -drive file=a -drive file=b"
989 @end example
990 is interpreted like:
991 @example
992 qemu-system-i386 -hda a -hdb b
993 @end example
994 ETEXI
996 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
997 "-mtdblock file use 'file' as on-board Flash memory image\n",
998 QEMU_ARCH_ALL)
999 STEXI
1000 @item -mtdblock @var{file}
1001 @findex -mtdblock
1002 Use @var{file} as on-board Flash memory image.
1003 ETEXI
1005 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
1006 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
1007 STEXI
1008 @item -sd @var{file}
1009 @findex -sd
1010 Use @var{file} as SecureDigital card image.
1011 ETEXI
1013 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
1014 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
1015 STEXI
1016 @item -pflash @var{file}
1017 @findex -pflash
1018 Use @var{file} as a parallel flash image.
1019 ETEXI
1021 DEF("snapshot", 0, QEMU_OPTION_snapshot,
1022 "-snapshot write to temporary files instead of disk image files\n",
1023 QEMU_ARCH_ALL)
1024 STEXI
1025 @item -snapshot
1026 @findex -snapshot
1027 Write to temporary files instead of disk image files. In this case,
1028 the raw disk image you use is not written back. You can however force
1029 the write back by pressing @key{C-a s} (@pxref{disk_images}).
1030 ETEXI
1032 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
1033 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1034 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1035 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1036 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1037 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1038 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1039 " [[,throttling.iops-size=is]]\n",
1040 QEMU_ARCH_ALL)
1042 STEXI
1044 @item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}]
1045 @findex -fsdev
1046 Define a new file system device. Valid options are:
1047 @table @option
1048 @item @var{fsdriver}
1049 This option specifies the fs driver backend to use.
1050 Currently "local", "handle" and "proxy" file system drivers are supported.
1051 @item id=@var{id}
1052 Specifies identifier for this device
1053 @item path=@var{path}
1054 Specifies the export path for the file system device. Files under
1055 this path will be available to the 9p client on the guest.
1056 @item security_model=@var{security_model}
1057 Specifies the security model to be used for this export path.
1058 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1059 In "passthrough" security model, files are stored using the same
1060 credentials as they are created on the guest. This requires QEMU
1061 to run as root. In "mapped-xattr" security model, some of the file
1062 attributes like uid, gid, mode bits and link target are stored as
1063 file attributes. For "mapped-file" these attributes are stored in the
1064 hidden .virtfs_metadata directory. Directories exported by this security model cannot
1065 interact with other unix tools. "none" security model is same as
1066 passthrough except the sever won't report failures if it fails to
1067 set file attributes like ownership. Security model is mandatory
1068 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1069 security model as a parameter.
1070 @item writeout=@var{writeout}
1071 This is an optional argument. The only supported value is "immediate".
1072 This means that host page cache will be used to read and write data but
1073 write notification will be sent to the guest only when the data has been
1074 reported as written by the storage subsystem.
1075 @item readonly
1076 Enables exporting 9p share as a readonly mount for guests. By default
1077 read-write access is given.
1078 @item socket=@var{socket}
1079 Enables proxy filesystem driver to use passed socket file for communicating
1080 with virtfs-proxy-helper
1081 @item sock_fd=@var{sock_fd}
1082 Enables proxy filesystem driver to use passed socket descriptor for
1083 communicating with virtfs-proxy-helper. Usually a helper like libvirt
1084 will create socketpair and pass one of the fds as sock_fd
1085 @item fmode=@var{fmode}
1086 Specifies the default mode for newly created files on the host. Works only
1087 with security models "mapped-xattr" and "mapped-file".
1088 @item dmode=@var{dmode}
1089 Specifies the default mode for newly created directories on the host. Works
1090 only with security models "mapped-xattr" and "mapped-file".
1091 @end table
1093 -fsdev option is used along with -device driver "virtio-9p-pci".
1094 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
1095 Options for virtio-9p-pci driver are:
1096 @table @option
1097 @item fsdev=@var{id}
1098 Specifies the id value specified along with -fsdev option
1099 @item mount_tag=@var{mount_tag}
1100 Specifies the tag name to be used by the guest to mount this export point
1101 @end table
1103 ETEXI
1105 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
1106 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1107 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1108 QEMU_ARCH_ALL)
1110 STEXI
1112 @item -virtfs @var{fsdriver}[,path=@var{path}],mount_tag=@var{mount_tag}[,security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}]
1113 @findex -virtfs
1115 The general form of a Virtual File system pass-through options are:
1116 @table @option
1117 @item @var{fsdriver}
1118 This option specifies the fs driver backend to use.
1119 Currently "local", "handle" and "proxy" file system drivers are supported.
1120 @item id=@var{id}
1121 Specifies identifier for this device
1122 @item path=@var{path}
1123 Specifies the export path for the file system device. Files under
1124 this path will be available to the 9p client on the guest.
1125 @item security_model=@var{security_model}
1126 Specifies the security model to be used for this export path.
1127 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1128 In "passthrough" security model, files are stored using the same
1129 credentials as they are created on the guest. This requires QEMU
1130 to run as root. In "mapped-xattr" security model, some of the file
1131 attributes like uid, gid, mode bits and link target are stored as
1132 file attributes. For "mapped-file" these attributes are stored in the
1133 hidden .virtfs_metadata directory. Directories exported by this security model cannot
1134 interact with other unix tools. "none" security model is same as
1135 passthrough except the sever won't report failures if it fails to
1136 set file attributes like ownership. Security model is mandatory only
1137 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1138 model as a parameter.
1139 @item writeout=@var{writeout}
1140 This is an optional argument. The only supported value is "immediate".
1141 This means that host page cache will be used to read and write data but
1142 write notification will be sent to the guest only when the data has been
1143 reported as written by the storage subsystem.
1144 @item readonly
1145 Enables exporting 9p share as a readonly mount for guests. By default
1146 read-write access is given.
1147 @item socket=@var{socket}
1148 Enables proxy filesystem driver to use passed socket file for
1149 communicating with virtfs-proxy-helper. Usually a helper like libvirt
1150 will create socketpair and pass one of the fds as sock_fd
1151 @item sock_fd
1152 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
1153 descriptor for interfacing with virtfs-proxy-helper
1154 @item fmode=@var{fmode}
1155 Specifies the default mode for newly created files on the host. Works only
1156 with security models "mapped-xattr" and "mapped-file".
1157 @item dmode=@var{dmode}
1158 Specifies the default mode for newly created directories on the host. Works
1159 only with security models "mapped-xattr" and "mapped-file".
1160 @end table
1161 ETEXI
1163 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
1164 "-virtfs_synth Create synthetic file system image\n",
1165 QEMU_ARCH_ALL)
1166 STEXI
1167 @item -virtfs_synth
1168 @findex -virtfs_synth
1169 Create synthetic file system image
1170 ETEXI
1172 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
1173 "-iscsi [user=user][,password=password]\n"
1174 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1175 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
1176 " [,timeout=timeout]\n"
1177 " iSCSI session parameters\n", QEMU_ARCH_ALL)
1179 STEXI
1180 @item -iscsi
1181 @findex -iscsi
1182 Configure iSCSI session parameters.
1183 ETEXI
1185 STEXI
1186 @end table
1187 ETEXI
1188 DEFHEADING()
1190 DEFHEADING(USB options:)
1191 STEXI
1192 @table @option
1193 ETEXI
1195 DEF("usb", 0, QEMU_OPTION_usb,
1196 "-usb enable the USB driver (if it is not used by default yet)\n",
1197 QEMU_ARCH_ALL)
1198 STEXI
1199 @item -usb
1200 @findex -usb
1201 Enable the USB driver (if it is not used by default yet).
1202 ETEXI
1204 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
1205 "-usbdevice name add the host or guest USB device 'name'\n",
1206 QEMU_ARCH_ALL)
1207 STEXI
1209 @item -usbdevice @var{devname}
1210 @findex -usbdevice
1211 Add the USB device @var{devname}. Note that this option is deprecated,
1212 please use @code{-device usb-...} instead. @xref{usb_devices}.
1214 @table @option
1216 @item mouse
1217 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1219 @item tablet
1220 Pointer device that uses absolute coordinates (like a touchscreen). This
1221 means QEMU is able to report the mouse position without having to grab the
1222 mouse. Also overrides the PS/2 mouse emulation when activated.
1224 @item braille
1225 Braille device. This will use BrlAPI to display the braille output on a real
1226 or fake device.
1228 @end table
1229 ETEXI
1231 STEXI
1232 @end table
1233 ETEXI
1234 DEFHEADING()
1236 DEFHEADING(Display options:)
1237 STEXI
1238 @table @option
1239 ETEXI
1241 DEF("display", HAS_ARG, QEMU_OPTION_display,
1242 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1243 " [,window_close=on|off][,gl=on|core|es|off]\n"
1244 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1245 "-display vnc=<display>[,<optargs>]\n"
1246 "-display curses\n"
1247 "-display none"
1248 " select display type\n"
1249 "The default display is equivalent to\n"
1250 #if defined(CONFIG_GTK)
1251 "\t\"-display gtk\"\n"
1252 #elif defined(CONFIG_SDL)
1253 "\t\"-display sdl\"\n"
1254 #elif defined(CONFIG_COCOA)
1255 "\t\"-display cocoa\"\n"
1256 #elif defined(CONFIG_VNC)
1257 "\t\"-vnc localhost:0,to=99,id=default\"\n"
1258 #else
1259 "\t\"-display none\"\n"
1260 #endif
1261 , QEMU_ARCH_ALL)
1262 STEXI
1263 @item -display @var{type}
1264 @findex -display
1265 Select type of display to use. This option is a replacement for the
1266 old style -sdl/-curses/... options. Valid values for @var{type} are
1267 @table @option
1268 @item sdl
1269 Display video output via SDL (usually in a separate graphics
1270 window; see the SDL documentation for other possibilities).
1271 @item curses
1272 Display video output via curses. For graphics device models which
1273 support a text mode, QEMU can display this output using a
1274 curses/ncurses interface. Nothing is displayed when the graphics
1275 device is in graphical mode or if the graphics device does not support
1276 a text mode. Generally only the VGA device models support text mode.
1277 @item none
1278 Do not display video output. The guest will still see an emulated
1279 graphics card, but its output will not be displayed to the QEMU
1280 user. This option differs from the -nographic option in that it
1281 only affects what is done with video output; -nographic also changes
1282 the destination of the serial and parallel port data.
1283 @item gtk
1284 Display video output in a GTK window. This interface provides drop-down
1285 menus and other UI elements to configure and control the VM during
1286 runtime.
1287 @item vnc
1288 Start a VNC server on display <arg>
1289 @end table
1290 ETEXI
1292 DEF("nographic", 0, QEMU_OPTION_nographic,
1293 "-nographic disable graphical output and redirect serial I/Os to console\n",
1294 QEMU_ARCH_ALL)
1295 STEXI
1296 @item -nographic
1297 @findex -nographic
1298 Normally, if QEMU is compiled with graphical window support, it displays
1299 output such as guest graphics, guest console, and the QEMU monitor in a
1300 window. With this option, you can totally disable graphical output so
1301 that QEMU is a simple command line application. The emulated serial port
1302 is redirected on the console and muxed with the monitor (unless
1303 redirected elsewhere explicitly). Therefore, you can still use QEMU to
1304 debug a Linux kernel with a serial console. Use @key{C-a h} for help on
1305 switching between the console and monitor.
1306 ETEXI
1308 DEF("curses", 0, QEMU_OPTION_curses,
1309 "-curses shorthand for -display curses\n",
1310 QEMU_ARCH_ALL)
1311 STEXI
1312 @item -curses
1313 @findex -curses
1314 Normally, if QEMU is compiled with graphical window support, it displays
1315 output such as guest graphics, guest console, and the QEMU monitor in a
1316 window. With this option, QEMU can display the VGA output when in text
1317 mode using a curses/ncurses interface. Nothing is displayed in graphical
1318 mode.
1319 ETEXI
1321 DEF("no-frame", 0, QEMU_OPTION_no_frame,
1322 "-no-frame open SDL window without a frame and window decorations\n",
1323 QEMU_ARCH_ALL)
1324 STEXI
1325 @item -no-frame
1326 @findex -no-frame
1327 Do not use decorations for SDL windows and start them using the whole
1328 available screen space. This makes the using QEMU in a dedicated desktop
1329 workspace more convenient.
1330 ETEXI
1332 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1333 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1334 QEMU_ARCH_ALL)
1335 STEXI
1336 @item -alt-grab
1337 @findex -alt-grab
1338 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1339 affects the special keys (for fullscreen, monitor-mode switching, etc).
1340 ETEXI
1342 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1343 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1344 QEMU_ARCH_ALL)
1345 STEXI
1346 @item -ctrl-grab
1347 @findex -ctrl-grab
1348 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1349 affects the special keys (for fullscreen, monitor-mode switching, etc).
1350 ETEXI
1352 DEF("no-quit", 0, QEMU_OPTION_no_quit,
1353 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
1354 STEXI
1355 @item -no-quit
1356 @findex -no-quit
1357 Disable SDL window close capability.
1358 ETEXI
1360 DEF("sdl", 0, QEMU_OPTION_sdl,
1361 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL)
1362 STEXI
1363 @item -sdl
1364 @findex -sdl
1365 Enable SDL.
1366 ETEXI
1368 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1369 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1370 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1371 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1372 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1373 " [,tls-ciphers=<list>]\n"
1374 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1375 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1376 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1377 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1378 " [,jpeg-wan-compression=[auto|never|always]]\n"
1379 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1380 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1381 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1382 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1383 " [,gl=[on|off]][,rendernode=<file>]\n"
1384 " enable spice\n"
1385 " at least one of {port, tls-port} is mandatory\n",
1386 QEMU_ARCH_ALL)
1387 STEXI
1388 @item -spice @var{option}[,@var{option}[,...]]
1389 @findex -spice
1390 Enable the spice remote desktop protocol. Valid options are
1392 @table @option
1394 @item port=<nr>
1395 Set the TCP port spice is listening on for plaintext channels.
1397 @item addr=<addr>
1398 Set the IP address spice is listening on. Default is any address.
1400 @item ipv4
1401 @itemx ipv6
1402 @itemx unix
1403 Force using the specified IP version.
1405 @item password=<secret>
1406 Set the password you need to authenticate.
1408 @item sasl
1409 Require that the client use SASL to authenticate with the spice.
1410 The exact choice of authentication method used is controlled from the
1411 system / user's SASL configuration file for the 'qemu' service. This
1412 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1413 unprivileged user, an environment variable SASL_CONF_PATH can be used
1414 to make it search alternate locations for the service config.
1415 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1416 it is recommended that SASL always be combined with the 'tls' and
1417 'x509' settings to enable use of SSL and server certificates. This
1418 ensures a data encryption preventing compromise of authentication
1419 credentials.
1421 @item disable-ticketing
1422 Allow client connects without authentication.
1424 @item disable-copy-paste
1425 Disable copy paste between the client and the guest.
1427 @item disable-agent-file-xfer
1428 Disable spice-vdagent based file-xfer between the client and the guest.
1430 @item tls-port=<nr>
1431 Set the TCP port spice is listening on for encrypted channels.
1433 @item x509-dir=<dir>
1434 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1436 @item x509-key-file=<file>
1437 @itemx x509-key-password=<file>
1438 @itemx x509-cert-file=<file>
1439 @itemx x509-cacert-file=<file>
1440 @itemx x509-dh-key-file=<file>
1441 The x509 file names can also be configured individually.
1443 @item tls-ciphers=<list>
1444 Specify which ciphers to use.
1446 @item tls-channel=[main|display|cursor|inputs|record|playback]
1447 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1448 Force specific channel to be used with or without TLS encryption. The
1449 options can be specified multiple times to configure multiple
1450 channels. The special name "default" can be used to set the default
1451 mode. For channels which are not explicitly forced into one mode the
1452 spice client is allowed to pick tls/plaintext as he pleases.
1454 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1455 Configure image compression (lossless).
1456 Default is auto_glz.
1458 @item jpeg-wan-compression=[auto|never|always]
1459 @itemx zlib-glz-wan-compression=[auto|never|always]
1460 Configure wan image compression (lossy for slow links).
1461 Default is auto.
1463 @item streaming-video=[off|all|filter]
1464 Configure video stream detection. Default is off.
1466 @item agent-mouse=[on|off]
1467 Enable/disable passing mouse events via vdagent. Default is on.
1469 @item playback-compression=[on|off]
1470 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1472 @item seamless-migration=[on|off]
1473 Enable/disable spice seamless migration. Default is off.
1475 @item gl=[on|off]
1476 Enable/disable OpenGL context. Default is off.
1478 @item rendernode=<file>
1479 DRM render node for OpenGL rendering. If not specified, it will pick
1480 the first available. (Since 2.9)
1482 @end table
1483 ETEXI
1485 DEF("portrait", 0, QEMU_OPTION_portrait,
1486 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1487 QEMU_ARCH_ALL)
1488 STEXI
1489 @item -portrait
1490 @findex -portrait
1491 Rotate graphical output 90 deg left (only PXA LCD).
1492 ETEXI
1494 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1495 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1496 QEMU_ARCH_ALL)
1497 STEXI
1498 @item -rotate @var{deg}
1499 @findex -rotate
1500 Rotate graphical output some deg left (only PXA LCD).
1501 ETEXI
1503 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1504 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1505 " select video card type\n", QEMU_ARCH_ALL)
1506 STEXI
1507 @item -vga @var{type}
1508 @findex -vga
1509 Select type of VGA card to emulate. Valid values for @var{type} are
1510 @table @option
1511 @item cirrus
1512 Cirrus Logic GD5446 Video card. All Windows versions starting from
1513 Windows 95 should recognize and use this graphic card. For optimal
1514 performances, use 16 bit color depth in the guest and the host OS.
1515 (This card was the default before QEMU 2.2)
1516 @item std
1517 Standard VGA card with Bochs VBE extensions. If your guest OS
1518 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1519 to use high resolution modes (>= 1280x1024x16) then you should use
1520 this option. (This card is the default since QEMU 2.2)
1521 @item vmware
1522 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1523 recent XFree86/XOrg server or Windows guest with a driver for this
1524 card.
1525 @item qxl
1526 QXL paravirtual graphic card. It is VGA compatible (including VESA
1527 2.0 VBE support). Works best with qxl guest drivers installed though.
1528 Recommended choice when using the spice protocol.
1529 @item tcx
1530 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1531 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1532 fixed resolution of 1024x768.
1533 @item cg3
1534 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1535 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1536 resolutions aimed at people wishing to run older Solaris versions.
1537 @item virtio
1538 Virtio VGA card.
1539 @item none
1540 Disable VGA card.
1541 @end table
1542 ETEXI
1544 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1545 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1546 STEXI
1547 @item -full-screen
1548 @findex -full-screen
1549 Start in full screen.
1550 ETEXI
1552 DEF("g", 1, QEMU_OPTION_g ,
1553 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1554 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1555 STEXI
1556 @item -g @var{width}x@var{height}[x@var{depth}]
1557 @findex -g
1558 Set the initial graphical resolution and depth (PPC, SPARC only).
1559 ETEXI
1561 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1562 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1563 STEXI
1564 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1565 @findex -vnc
1566 Normally, if QEMU is compiled with graphical window support, it displays
1567 output such as guest graphics, guest console, and the QEMU monitor in a
1568 window. With this option, you can have QEMU listen on VNC display
1569 @var{display} and redirect the VGA display over the VNC session. It is
1570 very useful to enable the usb tablet device when using this option
1571 (option @option{-device usb-tablet}). When using the VNC display, you
1572 must use the @option{-k} parameter to set the keyboard layout if you are
1573 not using en-us. Valid syntax for the @var{display} is
1575 @table @option
1577 @item to=@var{L}
1579 With this option, QEMU will try next available VNC @var{display}s, until the
1580 number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1581 available, e.g. port 5900+@var{display} is already used by another
1582 application. By default, to=0.
1584 @item @var{host}:@var{d}
1586 TCP connections will only be allowed from @var{host} on display @var{d}.
1587 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1588 be omitted in which case the server will accept connections from any host.
1590 @item unix:@var{path}
1592 Connections will be allowed over UNIX domain sockets where @var{path} is the
1593 location of a unix socket to listen for connections on.
1595 @item none
1597 VNC is initialized but not started. The monitor @code{change} command
1598 can be used to later start the VNC server.
1600 @end table
1602 Following the @var{display} value there may be one or more @var{option} flags
1603 separated by commas. Valid options are
1605 @table @option
1607 @item reverse
1609 Connect to a listening VNC client via a ``reverse'' connection. The
1610 client is specified by the @var{display}. For reverse network
1611 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1612 is a TCP port number, not a display number.
1614 @item websocket
1616 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1617 If a bare @var{websocket} option is given, the Websocket port is
1618 5700+@var{display}. An alternative port can be specified with the
1619 syntax @code{websocket}=@var{port}.
1621 If @var{host} is specified connections will only be allowed from this host.
1622 It is possible to control the websocket listen address independently, using
1623 the syntax @code{websocket}=@var{host}:@var{port}.
1625 If no TLS credentials are provided, the websocket connection runs in
1626 unencrypted mode. If TLS credentials are provided, the websocket connection
1627 requires encrypted client connections.
1629 @item password
1631 Require that password based authentication is used for client connections.
1633 The password must be set separately using the @code{set_password} command in
1634 the @ref{pcsys_monitor}. The syntax to change your password is:
1635 @code{set_password <protocol> <password>} where <protocol> could be either
1636 "vnc" or "spice".
1638 If you would like to change <protocol> password expiration, you should use
1639 @code{expire_password <protocol> <expiration-time>} where expiration time could
1640 be one of the following options: now, never, +seconds or UNIX time of
1641 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1642 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1643 date and time).
1645 You can also use keywords "now" or "never" for the expiration time to
1646 allow <protocol> password to expire immediately or never expire.
1648 @item tls-creds=@var{ID}
1650 Provides the ID of a set of TLS credentials to use to secure the
1651 VNC server. They will apply to both the normal VNC server socket
1652 and the websocket socket (if enabled). Setting TLS credentials
1653 will cause the VNC server socket to enable the VeNCrypt auth
1654 mechanism. The credentials should have been previously created
1655 using the @option{-object tls-creds} argument.
1657 The @option{tls-creds} parameter obsoletes the @option{tls},
1658 @option{x509}, and @option{x509verify} options, and as such
1659 it is not permitted to set both new and old type options at
1660 the same time.
1662 @item tls
1664 Require that client use TLS when communicating with the VNC server. This
1665 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1666 attack. It is recommended that this option be combined with either the
1667 @option{x509} or @option{x509verify} options.
1669 This option is now deprecated in favor of using the @option{tls-creds}
1670 argument.
1672 @item x509=@var{/path/to/certificate/dir}
1674 Valid if @option{tls} is specified. Require that x509 credentials are used
1675 for negotiating the TLS session. The server will send its x509 certificate
1676 to the client. It is recommended that a password be set on the VNC server
1677 to provide authentication of the client when this is used. The path following
1678 this option specifies where the x509 certificates are to be loaded from.
1679 See the @ref{vnc_security} section for details on generating certificates.
1681 This option is now deprecated in favour of using the @option{tls-creds}
1682 argument.
1684 @item x509verify=@var{/path/to/certificate/dir}
1686 Valid if @option{tls} is specified. Require that x509 credentials are used
1687 for negotiating the TLS session. The server will send its x509 certificate
1688 to the client, and request that the client send its own x509 certificate.
1689 The server will validate the client's certificate against the CA certificate,
1690 and reject clients when validation fails. If the certificate authority is
1691 trusted, this is a sufficient authentication mechanism. You may still wish
1692 to set a password on the VNC server as a second authentication layer. The
1693 path following this option specifies where the x509 certificates are to
1694 be loaded from. See the @ref{vnc_security} section for details on generating
1695 certificates.
1697 This option is now deprecated in favour of using the @option{tls-creds}
1698 argument.
1700 @item sasl
1702 Require that the client use SASL to authenticate with the VNC server.
1703 The exact choice of authentication method used is controlled from the
1704 system / user's SASL configuration file for the 'qemu' service. This
1705 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1706 unprivileged user, an environment variable SASL_CONF_PATH can be used
1707 to make it search alternate locations for the service config.
1708 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1709 it is recommended that SASL always be combined with the 'tls' and
1710 'x509' settings to enable use of SSL and server certificates. This
1711 ensures a data encryption preventing compromise of authentication
1712 credentials. See the @ref{vnc_security} section for details on using
1713 SASL authentication.
1715 @item acl
1717 Turn on access control lists for checking of the x509 client certificate
1718 and SASL party. For x509 certs, the ACL check is made against the
1719 certificate's distinguished name. This is something that looks like
1720 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1721 made against the username, which depending on the SASL plugin, may
1722 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1723 When the @option{acl} flag is set, the initial access list will be
1724 empty, with a @code{deny} policy. Thus no one will be allowed to
1725 use the VNC server until the ACLs have been loaded. This can be
1726 achieved using the @code{acl} monitor command.
1728 @item lossy
1730 Enable lossy compression methods (gradient, JPEG, ...). If this
1731 option is set, VNC client may receive lossy framebuffer updates
1732 depending on its encoding settings. Enabling this option can save
1733 a lot of bandwidth at the expense of quality.
1735 @item non-adaptive
1737 Disable adaptive encodings. Adaptive encodings are enabled by default.
1738 An adaptive encoding will try to detect frequently updated screen regions,
1739 and send updates in these regions using a lossy encoding (like JPEG).
1740 This can be really helpful to save bandwidth when playing videos. Disabling
1741 adaptive encodings restores the original static behavior of encodings
1742 like Tight.
1744 @item share=[allow-exclusive|force-shared|ignore]
1746 Set display sharing policy. 'allow-exclusive' allows clients to ask
1747 for exclusive access. As suggested by the rfb spec this is
1748 implemented by dropping other connections. Connecting multiple
1749 clients in parallel requires all clients asking for a shared session
1750 (vncviewer: -shared switch). This is the default. 'force-shared'
1751 disables exclusive client access. Useful for shared desktop sessions,
1752 where you don't want someone forgetting specify -shared disconnect
1753 everybody else. 'ignore' completely ignores the shared flag and
1754 allows everybody connect unconditionally. Doesn't conform to the rfb
1755 spec but is traditional QEMU behavior.
1757 @item key-delay-ms
1759 Set keyboard delay, for key down and key up events, in milliseconds.
1760 Default is 10. Keyboards are low-bandwidth devices, so this slowdown
1761 can help the device and guest to keep up and not lose events in case
1762 events are arriving in bulk. Possible causes for the latter are flaky
1763 network connections, or scripts for automated testing.
1765 @end table
1766 ETEXI
1768 STEXI
1769 @end table
1770 ETEXI
1771 ARCHHEADING(, QEMU_ARCH_I386)
1773 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1774 STEXI
1775 @table @option
1776 ETEXI
1778 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1779 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1780 QEMU_ARCH_I386)
1781 STEXI
1782 @item -win2k-hack
1783 @findex -win2k-hack
1784 Use it when installing Windows 2000 to avoid a disk full bug. After
1785 Windows 2000 is installed, you no longer need this option (this option
1786 slows down the IDE transfers).
1787 ETEXI
1789 HXCOMM Deprecated by -rtc
1790 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1792 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1793 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1794 QEMU_ARCH_I386)
1795 STEXI
1796 @item -no-fd-bootchk
1797 @findex -no-fd-bootchk
1798 Disable boot signature checking for floppy disks in BIOS. May
1799 be needed to boot from old floppy disks.
1800 ETEXI
1802 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1803 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1804 STEXI
1805 @item -no-acpi
1806 @findex -no-acpi
1807 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1808 it if your guest OS complains about ACPI problems (PC target machine
1809 only).
1810 ETEXI
1812 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1813 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1814 STEXI
1815 @item -no-hpet
1816 @findex -no-hpet
1817 Disable HPET support.
1818 ETEXI
1820 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1821 "-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,{data|file}=file1[:file2]...]\n"
1822 " ACPI table description\n", QEMU_ARCH_I386)
1823 STEXI
1824 @item -acpitable [sig=@var{str}][,rev=@var{n}][,oem_id=@var{str}][,oem_table_id=@var{str}][,oem_rev=@var{n}] [,asl_compiler_id=@var{str}][,asl_compiler_rev=@var{n}][,data=@var{file1}[:@var{file2}]...]
1825 @findex -acpitable
1826 Add ACPI table with specified header fields and context from specified files.
1827 For file=, take whole ACPI table from the specified files, including all
1828 ACPI headers (possible overridden by other options).
1829 For data=, only data
1830 portion of the table is used, all header information is specified in the
1831 command line.
1832 If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1833 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1834 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1835 spec.
1836 ETEXI
1838 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1839 "-smbios file=binary\n"
1840 " load SMBIOS entry from binary file\n"
1841 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1842 " [,uefi=on|off]\n"
1843 " specify SMBIOS type 0 fields\n"
1844 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1845 " [,uuid=uuid][,sku=str][,family=str]\n"
1846 " specify SMBIOS type 1 fields\n"
1847 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1848 " [,asset=str][,location=str]\n"
1849 " specify SMBIOS type 2 fields\n"
1850 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1851 " [,sku=str]\n"
1852 " specify SMBIOS type 3 fields\n"
1853 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1854 " [,asset=str][,part=str]\n"
1855 " specify SMBIOS type 4 fields\n"
1856 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1857 " [,asset=str][,part=str][,speed=%d]\n"
1858 " specify SMBIOS type 17 fields\n",
1859 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1860 STEXI
1861 @item -smbios file=@var{binary}
1862 @findex -smbios
1863 Load SMBIOS entry from binary file.
1865 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1866 Specify SMBIOS type 0 fields
1868 @item -smbios type=1[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,uuid=@var{uuid}][,sku=@var{str}][,family=@var{str}]
1869 Specify SMBIOS type 1 fields
1871 @item -smbios type=2[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,location=@var{str}][,family=@var{str}]
1872 Specify SMBIOS type 2 fields
1874 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1875 Specify SMBIOS type 3 fields
1877 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1878 Specify SMBIOS type 4 fields
1880 @item -smbios type=17[,loc_pfx=@var{str}][,bank=@var{str}][,manufacturer=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}][,speed=@var{%d}]
1881 Specify SMBIOS type 17 fields
1882 ETEXI
1884 STEXI
1885 @end table
1886 ETEXI
1887 DEFHEADING()
1889 DEFHEADING(Network options:)
1890 STEXI
1891 @table @option
1892 ETEXI
1894 HXCOMM Legacy slirp options (now moved to -net user):
1895 #ifdef CONFIG_SLIRP
1896 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1897 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1898 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1899 #ifndef _WIN32
1900 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1901 #endif
1902 #endif
1904 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1905 #ifdef CONFIG_SLIRP
1906 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1907 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1908 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1909 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n"
1910 " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1911 #ifndef _WIN32
1912 "[,smb=dir[,smbserver=addr]]\n"
1913 #endif
1914 " configure a user mode network backend with ID 'str',\n"
1915 " its DHCP server and optional services\n"
1916 #endif
1917 #ifdef _WIN32
1918 "-netdev tap,id=str,ifname=name\n"
1919 " configure a host TAP network backend with ID 'str'\n"
1920 #else
1921 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1922 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1923 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1924 " [,poll-us=n]\n"
1925 " configure a host TAP network backend with ID 'str'\n"
1926 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1927 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1928 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1929 " to deconfigure it\n"
1930 " use '[down]script=no' to disable script execution\n"
1931 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1932 " configure it\n"
1933 " use 'fd=h' to connect to an already opened TAP interface\n"
1934 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1935 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1936 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1937 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1938 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1939 " use vhost=on to enable experimental in kernel accelerator\n"
1940 " (only has effect for virtio guests which use MSIX)\n"
1941 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1942 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1943 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1944 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1945 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n"
1946 " spent on busy polling for vhost net\n"
1947 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1948 " configure a host TAP network backend with ID 'str' that is\n"
1949 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1950 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1951 #endif
1952 #ifdef __linux__
1953 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1954 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1955 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1956 " [,rxcookie=rxcookie][,offset=offset]\n"
1957 " configure a network backend with ID 'str' connected to\n"
1958 " an Ethernet over L2TPv3 pseudowire.\n"
1959 " Linux kernel 3.3+ as well as most routers can talk\n"
1960 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1961 " VM to a router and even VM to Host. It is a nearly-universal\n"
1962 " standard (RFC3391). Note - this implementation uses static\n"
1963 " pre-configured tunnels (same as the Linux kernel).\n"
1964 " use 'src=' to specify source address\n"
1965 " use 'dst=' to specify destination address\n"
1966 " use 'udp=on' to specify udp encapsulation\n"
1967 " use 'srcport=' to specify source udp port\n"
1968 " use 'dstport=' to specify destination udp port\n"
1969 " use 'ipv6=on' to force v6\n"
1970 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1971 " well as a weak security measure\n"
1972 " use 'rxcookie=0x012345678' to specify a rxcookie\n"
1973 " use 'txcookie=0x012345678' to specify a txcookie\n"
1974 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1975 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1976 " use 'pincounter=on' to work around broken counter handling in peer\n"
1977 " use 'offset=X' to add an extra offset between header and data\n"
1978 #endif
1979 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1980 " configure a network backend to connect to another network\n"
1981 " using a socket connection\n"
1982 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1983 " configure a network backend to connect to a multicast maddr and port\n"
1984 " use 'localaddr=addr' to specify the host address to send packets from\n"
1985 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1986 " configure a network backend to connect to another network\n"
1987 " using an UDP tunnel\n"
1988 #ifdef CONFIG_VDE
1989 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1990 " configure a network backend to connect to port 'n' of a vde switch\n"
1991 " running on host and listening for incoming connections on 'socketpath'.\n"
1992 " Use group 'groupname' and mode 'octalmode' to change default\n"
1993 " ownership and permissions for communication port.\n"
1994 #endif
1995 #ifdef CONFIG_NETMAP
1996 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1997 " attach to the existing netmap-enabled network interface 'name', or to a\n"
1998 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1999 " netmap device, defaults to '/dev/netmap')\n"
2000 #endif
2001 #ifdef CONFIG_POSIX
2002 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
2003 " configure a vhost-user network, backed by a chardev 'dev'\n"
2004 #endif
2005 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
2006 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL)
2007 DEF("nic", HAS_ARG, QEMU_OPTION_nic,
2008 "-nic [tap|bridge|"
2009 #ifdef CONFIG_SLIRP
2010 "user|"
2011 #endif
2012 #ifdef __linux__
2013 "l2tpv3|"
2014 #endif
2015 #ifdef CONFIG_VDE
2016 "vde|"
2017 #endif
2018 #ifdef CONFIG_NETMAP
2019 "netmap|"
2020 #endif
2021 #ifdef CONFIG_POSIX
2022 "vhost-user|"
2023 #endif
2024 "socket][,option][,...][mac=macaddr]\n"
2025 " initialize an on-board / default host NIC (using MAC address\n"
2026 " macaddr) and connect it to the given host network backend\n"
2027 "-nic none use it alone to have zero network devices (the default is to\n"
2028 " provided a 'user' network connection)\n",
2029 QEMU_ARCH_ALL)
2030 DEF("net", HAS_ARG, QEMU_OPTION_net,
2031 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2032 " configure or create an on-board (or machine default) NIC and\n"
2033 " connect it to hub 0 (please use -nic unless you need a hub)\n"
2034 "-net ["
2035 #ifdef CONFIG_SLIRP
2036 "user|"
2037 #endif
2038 "tap|"
2039 "bridge|"
2040 #ifdef CONFIG_VDE
2041 "vde|"
2042 #endif
2043 #ifdef CONFIG_NETMAP
2044 "netmap|"
2045 #endif
2046 "socket][,option][,option][,...]\n"
2047 " old way to initialize a host network interface\n"
2048 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2049 STEXI
2050 @item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn]
2051 @findex -nic
2052 This option is a shortcut for configuring both the on-board (default) guest
2053 NIC hardware and the host network backend in one go. The host backend options
2054 are the same as with the corresponding @option{-netdev} options below.
2055 The guest NIC model can be set with @option{model=@var{modelname}}.
2056 Use @option{model=help} to list the available device types.
2057 The hardware MAC address can be set with @option{mac=@var{macaddr}}.
2059 The following two example do exactly the same, to show how @option{-nic} can
2060 be used to shorten the command line length (note that the e1000 is the default
2061 on i386, so the @option{model=e1000} parameter could even be omitted here, too):
2062 @example
2063 qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32
2064 qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32
2065 @end example
2067 @item -nic none
2068 Indicate that no network devices should be configured. It is used to override
2069 the default configuration (default NIC with ``user'' host network backend)
2070 which is activated if no other networking options are provided.
2072 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2073 @findex -netdev
2074 Configure user mode host network backend which requires no administrator
2075 privilege to run. Valid options are:
2077 @table @option
2078 @item id=@var{id}
2079 Assign symbolic name for use in monitor commands.
2081 @item ipv4=on|off and ipv6=on|off
2082 Specify that either IPv4 or IPv6 must be enabled. If neither is specified
2083 both protocols are enabled.
2085 @item net=@var{addr}[/@var{mask}]
2086 Set IP network address the guest will see. Optionally specify the netmask,
2087 either in the form a.b.c.d or as number of valid top-most bits. Default is
2088 10.0.2.0/24.
2090 @item host=@var{addr}
2091 Specify the guest-visible address of the host. Default is the 2nd IP in the
2092 guest network, i.e. x.x.x.2.
2094 @item ipv6-net=@var{addr}[/@var{int}]
2095 Set IPv6 network address the guest will see (default is fec0::/64). The
2096 network prefix is given in the usual hexadecimal IPv6 address
2097 notation. The prefix size is optional, and is given as the number of
2098 valid top-most bits (default is 64).
2100 @item ipv6-host=@var{addr}
2101 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2102 the guest network, i.e. xxxx::2.
2104 @item restrict=on|off
2105 If this option is enabled, the guest will be isolated, i.e. it will not be
2106 able to contact the host and no guest IP packets will be routed over the host
2107 to the outside. This option does not affect any explicitly set forwarding rules.
2109 @item hostname=@var{name}
2110 Specifies the client hostname reported by the built-in DHCP server.
2112 @item dhcpstart=@var{addr}
2113 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2114 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2116 @item dns=@var{addr}
2117 Specify the guest-visible address of the virtual nameserver. The address must
2118 be different from the host address. Default is the 3rd IP in the guest network,
2119 i.e. x.x.x.3.
2121 @item ipv6-dns=@var{addr}
2122 Specify the guest-visible address of the IPv6 virtual nameserver. The address
2123 must be different from the host address. Default is the 3rd IP in the guest
2124 network, i.e. xxxx::3.
2126 @item dnssearch=@var{domain}
2127 Provides an entry for the domain-search list sent by the built-in
2128 DHCP server. More than one domain suffix can be transmitted by specifying
2129 this option multiple times. If supported, this will cause the guest to
2130 automatically try to append the given domain suffix(es) in case a domain name
2131 can not be resolved.
2133 Example:
2134 @example
2135 qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org
2136 @end example
2138 @item domainname=@var{domain}
2139 Specifies the client domain name reported by the built-in DHCP server.
2141 @item tftp=@var{dir}
2142 When using the user mode network stack, activate a built-in TFTP
2143 server. The files in @var{dir} will be exposed as the root of a TFTP server.
2144 The TFTP client on the guest must be configured in binary mode (use the command
2145 @code{bin} of the Unix TFTP client).
2147 @item bootfile=@var{file}
2148 When using the user mode network stack, broadcast @var{file} as the BOOTP
2149 filename. In conjunction with @option{tftp}, this can be used to network boot
2150 a guest from a local directory.
2152 Example (using pxelinux):
2153 @example
2154 qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \
2155 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2156 @end example
2158 @item smb=@var{dir}[,smbserver=@var{addr}]
2159 When using the user mode network stack, activate a built-in SMB
2160 server so that Windows OSes can access to the host files in @file{@var{dir}}
2161 transparently. The IP address of the SMB server can be set to @var{addr}. By
2162 default the 4th IP in the guest network is used, i.e. x.x.x.4.
2164 In the guest Windows OS, the line:
2165 @example
2166 10.0.2.4 smbserver
2167 @end example
2168 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2169 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2171 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2173 Note that a SAMBA server must be installed on the host OS.
2175 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2176 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2177 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2178 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2179 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2180 be bound to a specific host interface. If no connection type is set, TCP is
2181 used. This option can be given multiple times.
2183 For example, to redirect host X11 connection from screen 1 to guest
2184 screen 0, use the following:
2186 @example
2187 # on the host
2188 qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000
2189 # this host xterm should open in the guest X11 server
2190 xterm -display :1
2191 @end example
2193 To redirect telnet connections from host port 5555 to telnet port on
2194 the guest, use the following:
2196 @example
2197 # on the host
2198 qemu-system-i386 -nic user,hostfwd=tcp::5555-:23
2199 telnet localhost 5555
2200 @end example
2202 Then when you use on the host @code{telnet localhost 5555}, you
2203 connect to the guest telnet server.
2205 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2206 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2207 Forward guest TCP connections to the IP address @var{server} on port @var{port}
2208 to the character device @var{dev} or to a program executed by @var{cmd:command}
2209 which gets spawned for each connection. This option can be given multiple times.
2211 You can either use a chardev directly and have that one used throughout QEMU's
2212 lifetime, like in the following example:
2214 @example
2215 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
2216 # the guest accesses it
2217 qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321
2218 @end example
2220 Or you can execute a command on every TCP connection established by the guest,
2221 so that QEMU behaves similar to an inetd process for that virtual server:
2223 @example
2224 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
2225 # and connect the TCP stream to its stdin/stdout
2226 qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2227 @end example
2229 @end table
2231 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
2232 processed and applied to -net user. Mixing them with the new configuration
2233 syntax gives undefined results. Their use for new applications is discouraged
2234 as they will be removed from future versions.
2236 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2237 Configure a host TAP network backend with ID @var{id}.
2239 Use the network script @var{file} to configure it and the network script
2240 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
2241 automatically provides one. The default network configure script is
2242 @file{/etc/qemu-ifup} and the default network deconfigure script is
2243 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
2244 to disable script execution.
2246 If running QEMU as an unprivileged user, use the network helper
2247 @var{helper} to configure the TAP interface and attach it to the bridge.
2248 The default network helper executable is @file{/path/to/qemu-bridge-helper}
2249 and the default bridge device is @file{br0}.
2251 @option{fd}=@var{h} can be used to specify the handle of an already
2252 opened host TAP interface.
2254 Examples:
2256 @example
2257 #launch a QEMU instance with the default network script
2258 qemu-system-i386 linux.img -nic tap
2259 @end example
2261 @example
2262 #launch a QEMU instance with two NICs, each one connected
2263 #to a TAP device
2264 qemu-system-i386 linux.img \
2265 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \
2266 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1
2267 @end example
2269 @example
2270 #launch a QEMU instance with the default network helper to
2271 #connect a TAP device to bridge br0
2272 qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \
2273 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper"
2274 @end example
2276 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
2277 Connect a host TAP network interface to a host bridge device.
2279 Use the network helper @var{helper} to configure the TAP interface and
2280 attach it to the bridge. The default network helper executable is
2281 @file{/path/to/qemu-bridge-helper} and the default bridge
2282 device is @file{br0}.
2284 Examples:
2286 @example
2287 #launch a QEMU instance with the default network helper to
2288 #connect a TAP device to bridge br0
2289 qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1
2290 @end example
2292 @example
2293 #launch a QEMU instance with the default network helper to
2294 #connect a TAP device to bridge qemubr0
2295 qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1
2296 @end example
2298 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2300 This host network backend can be used to connect the guest's network to
2301 another QEMU virtual machine using a TCP socket connection. If @option{listen}
2302 is specified, QEMU waits for incoming connections on @var{port}
2303 (@var{host} is optional). @option{connect} is used to connect to
2304 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
2305 specifies an already opened TCP socket.
2307 Example:
2308 @example
2309 # launch a first QEMU instance
2310 qemu-system-i386 linux.img \
2311 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2312 -netdev socket,id=n1,listen=:1234
2313 # connect the network of this instance to the network of the first instance
2314 qemu-system-i386 linux.img \
2315 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \
2316 -netdev socket,id=n2,connect=127.0.0.1:1234
2317 @end example
2319 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2321 Configure a socket host network backend to share the guest's network traffic
2322 with another QEMU virtual machines using a UDP multicast socket, effectively
2323 making a bus for every QEMU with same multicast address @var{maddr} and @var{port}.
2324 NOTES:
2325 @enumerate
2326 @item
2327 Several QEMU can be running on different hosts and share same bus (assuming
2328 correct multicast setup for these hosts).
2329 @item
2330 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
2331 @url{http://user-mode-linux.sf.net}.
2332 @item
2333 Use @option{fd=h} to specify an already opened UDP multicast socket.
2334 @end enumerate
2336 Example:
2337 @example
2338 # launch one QEMU instance
2339 qemu-system-i386 linux.img \
2340 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2341 -netdev socket,id=n1,mcast=230.0.0.1:1234
2342 # launch another QEMU instance on same "bus"
2343 qemu-system-i386 linux.img \
2344 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \
2345 -netdev socket,id=n2,mcast=230.0.0.1:1234
2346 # launch yet another QEMU instance on same "bus"
2347 qemu-system-i386 linux.img \
2348 -device e1000,netdev=n3,macaddr=52:54:00:12:34:58 \
2349 -netdev socket,id=n3,mcast=230.0.0.1:1234
2350 @end example
2352 Example (User Mode Linux compat.):
2353 @example
2354 # launch QEMU instance (note mcast address selected is UML's default)
2355 qemu-system-i386 linux.img \
2356 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2357 -netdev socket,id=n1,mcast=239.192.168.1:1102
2358 # launch UML
2359 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2360 @end example
2362 Example (send packets from host's 1.2.3.4):
2363 @example
2364 qemu-system-i386 linux.img \
2365 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2366 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2367 @end example
2369 @item -netdev l2tpv3,id=@var{id},src=@var{srcaddr},dst=@var{dstaddr}[,srcport=@var{srcport}][,dstport=@var{dstport}],txsession=@var{txsession}[,rxsession=@var{rxsession}][,ipv6][,udp][,cookie64][,counter][,pincounter][,txcookie=@var{txcookie}][,rxcookie=@var{rxcookie}][,offset=@var{offset}]
2370 Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a
2371 popular protocol to transport Ethernet (and other Layer 2) data frames between
2372 two systems. It is present in routers, firewalls and the Linux kernel
2373 (from version 3.3 onwards).
2375 This transport allows a VM to communicate to another VM, router or firewall directly.
2377 @table @option
2378 @item src=@var{srcaddr}
2379 source address (mandatory)
2380 @item dst=@var{dstaddr}
2381 destination address (mandatory)
2382 @item udp
2383 select udp encapsulation (default is ip).
2384 @item srcport=@var{srcport}
2385 source udp port.
2386 @item dstport=@var{dstport}
2387 destination udp port.
2388 @item ipv6
2389 force v6, otherwise defaults to v4.
2390 @item rxcookie=@var{rxcookie}
2391 @itemx txcookie=@var{txcookie}
2392 Cookies are a weak form of security in the l2tpv3 specification.
2393 Their function is mostly to prevent misconfiguration. By default they are 32
2394 bit.
2395 @item cookie64
2396 Set cookie size to 64 bit instead of the default 32
2397 @item counter=off
2398 Force a 'cut-down' L2TPv3 with no counter as in
2399 draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2400 @item pincounter=on
2401 Work around broken counter handling in peer. This may also help on
2402 networks which have packet reorder.
2403 @item offset=@var{offset}
2404 Add an extra offset between header and data
2405 @end table
2407 For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2408 on the remote Linux host 1.2.3.4:
2409 @example
2410 # Setup tunnel on linux host using raw ip as encapsulation
2411 # on 1.2.3.4
2412 ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2413 encap udp udp_sport 16384 udp_dport 16384
2414 ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2415 0xFFFFFFFF peer_session_id 0xFFFFFFFF
2416 ifconfig vmtunnel0 mtu 1500
2417 ifconfig vmtunnel0 up
2418 brctl addif br-lan vmtunnel0
2421 # on 4.3.2.1
2422 # launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2424 qemu-system-i386 linux.img -device e1000,netdev=n1 \
2425 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter
2427 @end example
2429 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2430 Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and
2431 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2432 and MODE @var{octalmode} to change default ownership and permissions for
2433 communication port. This option is only available if QEMU has been compiled
2434 with vde support enabled.
2436 Example:
2437 @example
2438 # launch vde switch
2439 vde_switch -F -sock /tmp/myswitch
2440 # launch QEMU instance
2441 qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch
2442 @end example
2444 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2446 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2447 be a unix domain socket backed one. The vhost-user uses a specifically defined
2448 protocol to pass vhost ioctl replacement messages to an application on the other
2449 end of the socket. On non-MSIX guests, the feature can be forced with
2450 @var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2451 be created for multiqueue vhost-user.
2453 Example:
2454 @example
2455 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2456 -numa node,memdev=mem \
2457 -chardev socket,id=chr0,path=/path/to/socket \
2458 -netdev type=vhost-user,id=net0,chardev=chr0 \
2459 -device virtio-net-pci,netdev=net0
2460 @end example
2462 @item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}]
2464 Create a hub port on the emulated hub with ID @var{hubid}.
2466 The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a
2467 single netdev. Alternatively, you can also connect the hubport to another
2468 netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option.
2470 @item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2471 @findex -net
2472 Legacy option to configure or create an on-board (or machine default) Network
2473 Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e.
2474 the default hub), or to the netdev @var{nd}.
2475 The NIC is an e1000 by default on the PC target. Optionally, the MAC address
2476 can be changed to @var{mac}, the device address set to @var{addr} (PCI cards
2477 only), and a @var{name} can be assigned for use in monitor commands.
2478 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2479 that the card should have; this option currently only affects virtio cards; set
2480 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2481 NIC is created. QEMU can emulate several different models of network card.
2482 Use @code{-net nic,model=help} for a list of available devices for your target.
2484 @item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}]
2485 Configure a host network backend (with the options corresponding to the same
2486 @option{-netdev} option) and connect it to the emulated hub 0 (the default
2487 hub). Use @var{name} to specify the name of the hub port.
2488 ETEXI
2490 STEXI
2491 @end table
2492 ETEXI
2493 DEFHEADING()
2495 DEFHEADING(Character device options:)
2497 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2498 "-chardev help\n"
2499 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2500 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2501 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2502 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2503 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2504 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2505 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2506 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2507 " [,logfile=PATH][,logappend=on|off]\n"
2508 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2509 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2510 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2511 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2512 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2513 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2514 #ifdef _WIN32
2515 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2516 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2517 #else
2518 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2519 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2520 #endif
2521 #ifdef CONFIG_BRLAPI
2522 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2523 #endif
2524 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2525 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2526 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2527 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2528 #endif
2529 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2530 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2531 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2532 #endif
2533 #if defined(CONFIG_SPICE)
2534 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2535 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2536 #endif
2537 , QEMU_ARCH_ALL
2540 STEXI
2542 The general form of a character device option is:
2543 @table @option
2544 @item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}]
2545 @findex -chardev
2546 Backend is one of:
2547 @option{null},
2548 @option{socket},
2549 @option{udp},
2550 @option{msmouse},
2551 @option{vc},
2552 @option{ringbuf},
2553 @option{file},
2554 @option{pipe},
2555 @option{console},
2556 @option{serial},
2557 @option{pty},
2558 @option{stdio},
2559 @option{braille},
2560 @option{tty},
2561 @option{parallel},
2562 @option{parport},
2563 @option{spicevmc},
2564 @option{spiceport}.
2565 The specific backend will determine the applicable options.
2567 Use @code{-chardev help} to print all available chardev backend types.
2569 All devices must have an id, which can be any string up to 127 characters long.
2570 It is used to uniquely identify this device in other command line directives.
2572 A character device may be used in multiplexing mode by multiple front-ends.
2573 Specify @option{mux=on} to enable this mode.
2574 A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2575 backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2576 If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2577 create a multiplexer with your specified ID, and you can then configure multiple
2578 front ends to use that chardev ID for their input/output. Up to four different
2579 front ends can be connected to a single multiplexed chardev. (Without
2580 multiplexing enabled, a chardev can only be used by a single front end.)
2581 For instance you could use this to allow a single stdio chardev to be used by
2582 two serial ports and the QEMU monitor:
2584 @example
2585 -chardev stdio,mux=on,id=char0 \
2586 -mon chardev=char0,mode=readline \
2587 -serial chardev:char0 \
2588 -serial chardev:char0
2589 @end example
2591 You can have more than one multiplexer in a system configuration; for instance
2592 you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2593 multiplexed between the QEMU monitor and a parallel port:
2595 @example
2596 -chardev stdio,mux=on,id=char0 \
2597 -mon chardev=char0,mode=readline \
2598 -parallel chardev:char0 \
2599 -chardev tcp,...,mux=on,id=char1 \
2600 -serial chardev:char1 \
2601 -serial chardev:char1
2602 @end example
2604 When you're using a multiplexed character device, some escape sequences are
2605 interpreted in the input. @xref{mux_keys, Keys in the character backend
2606 multiplexer}.
2608 Note that some other command line options may implicitly create multiplexed
2609 character backends; for instance @option{-serial mon:stdio} creates a
2610 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2611 and @option{-nographic} also multiplexes the console and the monitor to
2612 stdio.
2614 There is currently no support for multiplexing in the other direction
2615 (where a single QEMU front end takes input and output from multiple chardevs).
2617 Every backend supports the @option{logfile} option, which supplies the path
2618 to a file to record all data transmitted via the backend. The @option{logappend}
2619 option controls whether the log file will be truncated or appended to when
2620 opened.
2622 @end table
2624 The available backends are:
2626 @table @option
2627 @item -chardev null,id=@var{id}
2628 A void device. This device will not emit any data, and will drop any data it
2629 receives. The null backend does not take any options.
2631 @item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,reconnect=@var{seconds}][,tls-creds=@var{id}]
2633 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2634 unix socket will be created if @option{path} is specified. Behaviour is
2635 undefined if TCP options are specified for a unix socket.
2637 @option{server} specifies that the socket shall be a listening socket.
2639 @option{nowait} specifies that QEMU should not block waiting for a client to
2640 connect to a listening socket.
2642 @option{telnet} specifies that traffic on the socket should interpret telnet
2643 escape sequences.
2645 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2646 the remote end goes away. qemu will delay this many seconds and then attempt
2647 to reconnect. Zero disables reconnecting, and is the default.
2649 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2650 and specifies the id of the TLS credentials to use for the handshake. The
2651 credentials must be previously created with the @option{-object tls-creds}
2652 argument.
2654 TCP and unix socket options are given below:
2656 @table @option
2658 @item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay]
2660 @option{host} for a listening socket specifies the local address to be bound.
2661 For a connecting socket species the remote host to connect to. @option{host} is
2662 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2664 @option{port} for a listening socket specifies the local port to be bound. For a
2665 connecting socket specifies the port on the remote host to connect to.
2666 @option{port} can be given as either a port number or a service name.
2667 @option{port} is required.
2669 @option{to} is only relevant to listening sockets. If it is specified, and
2670 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2671 to and including @option{to} until it succeeds. @option{to} must be specified
2672 as a port number.
2674 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2675 If neither is specified the socket may use either protocol.
2677 @option{nodelay} disables the Nagle algorithm.
2679 @item unix options: path=@var{path}
2681 @option{path} specifies the local path of the unix socket. @option{path} is
2682 required.
2684 @end table
2686 @item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6]
2688 Sends all traffic from the guest to a remote host over UDP.
2690 @option{host} specifies the remote host to connect to. If not specified it
2691 defaults to @code{localhost}.
2693 @option{port} specifies the port on the remote host to connect to. @option{port}
2694 is required.
2696 @option{localaddr} specifies the local address to bind to. If not specified it
2697 defaults to @code{0.0.0.0}.
2699 @option{localport} specifies the local port to bind to. If not specified any
2700 available local port will be used.
2702 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2703 If neither is specified the device may use either protocol.
2705 @item -chardev msmouse,id=@var{id}
2707 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2708 take any options.
2710 @item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]]
2712 Connect to a QEMU text console. @option{vc} may optionally be given a specific
2713 size.
2715 @option{width} and @option{height} specify the width and height respectively of
2716 the console, in pixels.
2718 @option{cols} and @option{rows} specify that the console be sized to fit a text
2719 console with the given dimensions.
2721 @item -chardev ringbuf,id=@var{id}[,size=@var{size}]
2723 Create a ring buffer with fixed size @option{size}.
2724 @var{size} must be a power of two and defaults to @code{64K}.
2726 @item -chardev file,id=@var{id},path=@var{path}
2728 Log all traffic received from the guest to a file.
2730 @option{path} specifies the path of the file to be opened. This file will be
2731 created if it does not already exist, and overwritten if it does. @option{path}
2732 is required.
2734 @item -chardev pipe,id=@var{id},path=@var{path}
2736 Create a two-way connection to the guest. The behaviour differs slightly between
2737 Windows hosts and other hosts:
2739 On Windows, a single duplex pipe will be created at
2740 @file{\\.pipe\@option{path}}.
2742 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2743 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2744 received by the guest. Data written by the guest can be read from
2745 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2746 be present.
2748 @option{path} forms part of the pipe path as described above. @option{path} is
2749 required.
2751 @item -chardev console,id=@var{id}
2753 Send traffic from the guest to QEMU's standard output. @option{console} does not
2754 take any options.
2756 @option{console} is only available on Windows hosts.
2758 @item -chardev serial,id=@var{id},path=@option{path}
2760 Send traffic from the guest to a serial device on the host.
2762 On Unix hosts serial will actually accept any tty device,
2763 not only serial lines.
2765 @option{path} specifies the name of the serial device to open.
2767 @item -chardev pty,id=@var{id}
2769 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2770 not take any options.
2772 @option{pty} is not available on Windows hosts.
2774 @item -chardev stdio,id=@var{id}[,signal=on|off]
2775 Connect to standard input and standard output of the QEMU process.
2777 @option{signal} controls if signals are enabled on the terminal, that includes
2778 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2779 default, use @option{signal=off} to disable it.
2781 @item -chardev braille,id=@var{id}
2783 Connect to a local BrlAPI server. @option{braille} does not take any options.
2785 @item -chardev tty,id=@var{id},path=@var{path}
2787 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2788 DragonFlyBSD hosts. It is an alias for @option{serial}.
2790 @option{path} specifies the path to the tty. @option{path} is required.
2792 @item -chardev parallel,id=@var{id},path=@var{path}
2793 @itemx -chardev parport,id=@var{id},path=@var{path}
2795 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2797 Connect to a local parallel port.
2799 @option{path} specifies the path to the parallel port device. @option{path} is
2800 required.
2802 @item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name}
2804 @option{spicevmc} is only available when spice support is built in.
2806 @option{debug} debug level for spicevmc
2808 @option{name} name of spice channel to connect to
2810 Connect to a spice virtual machine channel, such as vdiport.
2812 @item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name}
2814 @option{spiceport} is only available when spice support is built in.
2816 @option{debug} debug level for spicevmc
2818 @option{name} name of spice port to connect to
2820 Connect to a spice port, allowing a Spice client to handle the traffic
2821 identified by a name (preferably a fqdn).
2822 ETEXI
2824 STEXI
2825 @end table
2826 ETEXI
2827 DEFHEADING()
2829 DEFHEADING(Bluetooth(R) options:)
2830 STEXI
2831 @table @option
2832 ETEXI
2834 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2835 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2836 "-bt hci,host[:id]\n" \
2837 " use host's HCI with the given name\n" \
2838 "-bt hci[,vlan=n]\n" \
2839 " emulate a standard HCI in virtual scatternet 'n'\n" \
2840 "-bt vhci[,vlan=n]\n" \
2841 " add host computer to virtual scatternet 'n' using VHCI\n" \
2842 "-bt device:dev[,vlan=n]\n" \
2843 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2844 QEMU_ARCH_ALL)
2845 STEXI
2846 @item -bt hci[...]
2847 @findex -bt
2848 Defines the function of the corresponding Bluetooth HCI. -bt options
2849 are matched with the HCIs present in the chosen machine type. For
2850 example when emulating a machine with only one HCI built into it, only
2851 the first @code{-bt hci[...]} option is valid and defines the HCI's
2852 logic. The Transport Layer is decided by the machine type. Currently
2853 the machines @code{n800} and @code{n810} have one HCI and all other
2854 machines have none.
2856 @anchor{bt-hcis}
2857 The following three types are recognized:
2859 @table @option
2860 @item -bt hci,null
2861 (default) The corresponding Bluetooth HCI assumes no internal logic
2862 and will not respond to any HCI commands or emit events.
2864 @item -bt hci,host[:@var{id}]
2865 (@code{bluez} only) The corresponding HCI passes commands / events
2866 to / from the physical HCI identified by the name @var{id} (default:
2867 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2868 capable systems like Linux.
2870 @item -bt hci[,vlan=@var{n}]
2871 Add a virtual, standard HCI that will participate in the Bluetooth
2872 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2873 VLANs, devices inside a bluetooth network @var{n} can only communicate
2874 with other devices in the same network (scatternet).
2875 @end table
2877 @item -bt vhci[,vlan=@var{n}]
2878 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2879 to the host bluetooth stack instead of to the emulated target. This
2880 allows the host and target machines to participate in a common scatternet
2881 and communicate. Requires the Linux @code{vhci} driver installed. Can
2882 be used as following:
2884 @example
2885 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2886 @end example
2888 @item -bt device:@var{dev}[,vlan=@var{n}]
2889 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2890 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2891 currently:
2893 @table @option
2894 @item keyboard
2895 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2896 @end table
2897 ETEXI
2899 STEXI
2900 @end table
2901 ETEXI
2902 DEFHEADING()
2904 #ifdef CONFIG_TPM
2905 DEFHEADING(TPM device options:)
2907 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2908 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2909 " use path to provide path to a character device; default is /dev/tpm0\n"
2910 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2911 " not provided it will be searched for in /sys/class/misc/tpm?/device\n"
2912 "-tpmdev emulator,id=id,chardev=dev\n"
2913 " configure the TPM device using chardev backend\n",
2914 QEMU_ARCH_ALL)
2915 STEXI
2917 The general form of a TPM device option is:
2918 @table @option
2920 @item -tpmdev @var{backend},id=@var{id}[,@var{options}]
2921 @findex -tpmdev
2923 The specific backend type will determine the applicable options.
2924 The @code{-tpmdev} option creates the TPM backend and requires a
2925 @code{-device} option that specifies the TPM frontend interface model.
2927 Use @code{-tpmdev help} to print all available TPM backend types.
2929 @end table
2931 The available backends are:
2933 @table @option
2935 @item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path}
2937 (Linux-host only) Enable access to the host's TPM using the passthrough
2938 driver.
2940 @option{path} specifies the path to the host's TPM device, i.e., on
2941 a Linux host this would be @code{/dev/tpm0}.
2942 @option{path} is optional and by default @code{/dev/tpm0} is used.
2944 @option{cancel-path} specifies the path to the host TPM device's sysfs
2945 entry allowing for cancellation of an ongoing TPM command.
2946 @option{cancel-path} is optional and by default QEMU will search for the
2947 sysfs entry to use.
2949 Some notes about using the host's TPM with the passthrough driver:
2951 The TPM device accessed by the passthrough driver must not be
2952 used by any other application on the host.
2954 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2955 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2956 TPM again and may therefore not show a TPM-specific menu that would
2957 otherwise allow the user to configure the TPM, e.g., allow the user to
2958 enable/disable or activate/deactivate the TPM.
2959 Further, if TPM ownership is released from within a VM then the host's TPM
2960 will get disabled and deactivated. To enable and activate the
2961 TPM again afterwards, the host has to be rebooted and the user is
2962 required to enter the firmware's menu to enable and activate the TPM.
2963 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2965 To create a passthrough TPM use the following two options:
2966 @example
2967 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2968 @end example
2969 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2970 @code{tpmdev=tpm0} in the device option.
2972 @item -tpmdev emulator,id=@var{id},chardev=@var{dev}
2974 (Linux-host only) Enable access to a TPM emulator using Unix domain socket based
2975 chardev backend.
2977 @option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
2979 To create a TPM emulator backend device with chardev socket backend:
2980 @example
2982 -chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
2984 @end example
2986 ETEXI
2988 STEXI
2989 @end table
2990 ETEXI
2991 DEFHEADING()
2993 #endif
2995 DEFHEADING(Linux/Multiboot boot specific:)
2996 STEXI
2998 When using these options, you can use a given Linux or Multiboot
2999 kernel without installing it in the disk image. It can be useful
3000 for easier testing of various kernels.
3002 @table @option
3003 ETEXI
3005 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
3006 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
3007 STEXI
3008 @item -kernel @var{bzImage}
3009 @findex -kernel
3010 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
3011 or in multiboot format.
3012 ETEXI
3014 DEF("append", HAS_ARG, QEMU_OPTION_append, \
3015 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
3016 STEXI
3017 @item -append @var{cmdline}
3018 @findex -append
3019 Use @var{cmdline} as kernel command line
3020 ETEXI
3022 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
3023 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
3024 STEXI
3025 @item -initrd @var{file}
3026 @findex -initrd
3027 Use @var{file} as initial ram disk.
3029 @item -initrd "@var{file1} arg=foo,@var{file2}"
3031 This syntax is only available with multiboot.
3033 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3034 first module.
3035 ETEXI
3037 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
3038 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
3039 STEXI
3040 @item -dtb @var{file}
3041 @findex -dtb
3042 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3043 on boot.
3044 ETEXI
3046 STEXI
3047 @end table
3048 ETEXI
3049 DEFHEADING()
3051 DEFHEADING(Debug/Expert options:)
3052 STEXI
3053 @table @option
3054 ETEXI
3056 DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
3057 "-fw_cfg [name=]<name>,file=<file>\n"
3058 " add named fw_cfg entry with contents from file\n"
3059 "-fw_cfg [name=]<name>,string=<str>\n"
3060 " add named fw_cfg entry with contents from string\n",
3061 QEMU_ARCH_ALL)
3062 STEXI
3064 @item -fw_cfg [name=]@var{name},file=@var{file}
3065 @findex -fw_cfg
3066 Add named fw_cfg entry with contents from file @var{file}.
3068 @item -fw_cfg [name=]@var{name},string=@var{str}
3069 Add named fw_cfg entry with contents from string @var{str}.
3071 The terminating NUL character of the contents of @var{str} will not be
3072 included as part of the fw_cfg item data. To insert contents with
3073 embedded NUL characters, you have to use the @var{file} parameter.
3075 The fw_cfg entries are passed by QEMU through to the guest.
3077 Example:
3078 @example
3079 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3080 @end example
3081 creates an fw_cfg entry named opt/com.mycompany/blob with contents
3082 from ./my_blob.bin.
3084 ETEXI
3086 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
3087 "-serial dev redirect the serial port to char device 'dev'\n",
3088 QEMU_ARCH_ALL)
3089 STEXI
3090 @item -serial @var{dev}
3091 @findex -serial
3092 Redirect the virtual serial port to host character device
3093 @var{dev}. The default device is @code{vc} in graphical mode and
3094 @code{stdio} in non graphical mode.
3096 This option can be used several times to simulate up to 4 serial
3097 ports.
3099 Use @code{-serial none} to disable all serial ports.
3101 Available character devices are:
3102 @table @option
3103 @item vc[:@var{W}x@var{H}]
3104 Virtual console. Optionally, a width and height can be given in pixel with
3105 @example
3106 vc:800x600
3107 @end example
3108 It is also possible to specify width or height in characters:
3109 @example
3110 vc:80Cx24C
3111 @end example
3112 @item pty
3113 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
3114 @item none
3115 No device is allocated.
3116 @item null
3117 void device
3118 @item chardev:@var{id}
3119 Use a named character device defined with the @code{-chardev} option.
3120 @item /dev/XXX
3121 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3122 parameters are set according to the emulated ones.
3123 @item /dev/parport@var{N}
3124 [Linux only, parallel port only] Use host parallel port
3125 @var{N}. Currently SPP and EPP parallel port features can be used.
3126 @item file:@var{filename}
3127 Write output to @var{filename}. No character can be read.
3128 @item stdio
3129 [Unix only] standard input/output
3130 @item pipe:@var{filename}
3131 name pipe @var{filename}
3132 @item COM@var{n}
3133 [Windows only] Use host serial port @var{n}
3134 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3135 This implements UDP Net Console.
3136 When @var{remote_host} or @var{src_ip} are not specified
3137 they default to @code{0.0.0.0}.
3138 When not using a specified @var{src_port} a random port is automatically chosen.
3140 If you just want a simple readonly console you can use @code{netcat} or
3141 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3142 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3143 will appear in the netconsole session.
3145 If you plan to send characters back via netconsole or you want to stop
3146 and start QEMU a lot of times, you should have QEMU use the same
3147 source port each time by using something like @code{-serial
3148 udp::4555@@:4556} to QEMU. Another approach is to use a patched
3149 version of netcat which can listen to a TCP port and send and receive
3150 characters via udp. If you have a patched version of netcat which
3151 activates telnet remote echo and single char transfer, then you can
3152 use the following options to set up a netcat redirector to allow
3153 telnet on port 5555 to access the QEMU port.
3154 @table @code
3155 @item QEMU Options:
3156 -serial udp::4555@@:4556
3157 @item netcat options:
3158 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3159 @item telnet options:
3160 localhost 5555
3161 @end table
3163 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3164 The TCP Net Console has two modes of operation. It can send the serial
3165 I/O to a location or wait for a connection from a location. By default
3166 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
3167 the @var{server} option QEMU will wait for a client socket application
3168 to connect to the port before continuing, unless the @code{nowait}
3169 option was specified. The @code{nodelay} option disables the Nagle buffering
3170 algorithm. The @code{reconnect} option only applies if @var{noserver} is
3171 set, if the connection goes down it will attempt to reconnect at the
3172 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
3173 one TCP connection at a time is accepted. You can use @code{telnet} to
3174 connect to the corresponding character device.
3175 @table @code
3176 @item Example to send tcp console to 192.168.0.2 port 4444
3177 -serial tcp:192.168.0.2:4444
3178 @item Example to listen and wait on port 4444 for connection
3179 -serial tcp::4444,server
3180 @item Example to not wait and listen on ip 192.168.0.100 port 4444
3181 -serial tcp:192.168.0.100:4444,server,nowait
3182 @end table
3184 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3185 The telnet protocol is used instead of raw tcp sockets. The options
3186 work the same as if you had specified @code{-serial tcp}. The
3187 difference is that the port acts like a telnet server or client using
3188 telnet option negotiation. This will also allow you to send the
3189 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3190 sequence. Typically in unix telnet you do it with Control-] and then
3191 type "send break" followed by pressing the enter key.
3193 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3194 A unix domain socket is used instead of a tcp socket. The option works the
3195 same as if you had specified @code{-serial tcp} except the unix domain socket
3196 @var{path} is used for connections.
3198 @item mon:@var{dev_string}
3199 This is a special option to allow the monitor to be multiplexed onto
3200 another serial port. The monitor is accessed with key sequence of
3201 @key{Control-a} and then pressing @key{c}.
3202 @var{dev_string} should be any one of the serial devices specified
3203 above. An example to multiplex the monitor onto a telnet server
3204 listening on port 4444 would be:
3205 @table @code
3206 @item -serial mon:telnet::4444,server,nowait
3207 @end table
3208 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3209 QEMU any more but will be passed to the guest instead.
3211 @item braille
3212 Braille device. This will use BrlAPI to display the braille output on a real
3213 or fake device.
3215 @item msmouse
3216 Three button serial mouse. Configure the guest to use Microsoft protocol.
3217 @end table
3218 ETEXI
3220 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3221 "-parallel dev redirect the parallel port to char device 'dev'\n",
3222 QEMU_ARCH_ALL)
3223 STEXI
3224 @item -parallel @var{dev}
3225 @findex -parallel
3226 Redirect the virtual parallel port to host device @var{dev} (same
3227 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3228 be used to use hardware devices connected on the corresponding host
3229 parallel port.
3231 This option can be used several times to simulate up to 3 parallel
3232 ports.
3234 Use @code{-parallel none} to disable all parallel ports.
3235 ETEXI
3237 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3238 "-monitor dev redirect the monitor to char device 'dev'\n",
3239 QEMU_ARCH_ALL)
3240 STEXI
3241 @item -monitor @var{dev}
3242 @findex -monitor
3243 Redirect the monitor to host device @var{dev} (same devices as the
3244 serial port).
3245 The default device is @code{vc} in graphical mode and @code{stdio} in
3246 non graphical mode.
3247 Use @code{-monitor none} to disable the default monitor.
3248 ETEXI
3249 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3250 "-qmp dev like -monitor but opens in 'control' mode\n",
3251 QEMU_ARCH_ALL)
3252 STEXI
3253 @item -qmp @var{dev}
3254 @findex -qmp
3255 Like -monitor but opens in 'control' mode.
3256 ETEXI
3257 DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3258 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3259 QEMU_ARCH_ALL)
3260 STEXI
3261 @item -qmp-pretty @var{dev}
3262 @findex -qmp-pretty
3263 Like -qmp but uses pretty JSON formatting.
3264 ETEXI
3266 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3267 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL)
3268 STEXI
3269 @item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]
3270 @findex -mon
3271 Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing
3272 easing human reading and debugging.
3273 ETEXI
3275 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3276 "-debugcon dev redirect the debug console to char device 'dev'\n",
3277 QEMU_ARCH_ALL)
3278 STEXI
3279 @item -debugcon @var{dev}
3280 @findex -debugcon
3281 Redirect the debug console to host device @var{dev} (same devices as the
3282 serial port). The debug console is an I/O port which is typically port
3283 0xe9; writing to that I/O port sends output to this device.
3284 The default device is @code{vc} in graphical mode and @code{stdio} in
3285 non graphical mode.
3286 ETEXI
3288 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3289 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
3290 STEXI
3291 @item -pidfile @var{file}
3292 @findex -pidfile
3293 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3294 from a script.
3295 ETEXI
3297 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3298 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
3299 STEXI
3300 @item -singlestep
3301 @findex -singlestep
3302 Run the emulation in single step mode.
3303 ETEXI
3305 DEF("preconfig", 0, QEMU_OPTION_preconfig, \
3306 "--preconfig pause QEMU before machine is initialized (experimental)\n",
3307 QEMU_ARCH_ALL)
3308 STEXI
3309 @item --preconfig
3310 @findex --preconfig
3311 Pause QEMU for interactive configuration before the machine is created,
3312 which allows querying and configuring properties that will affect
3313 machine initialization. Use QMP command 'x-exit-preconfig' to exit
3314 the preconfig state and move to the next state (i.e. run guest if -S
3315 isn't used or pause the second time if -S is used). This option is
3316 experimental.
3317 ETEXI
3319 DEF("S", 0, QEMU_OPTION_S, \
3320 "-S freeze CPU at startup (use 'c' to start execution)\n",
3321 QEMU_ARCH_ALL)
3322 STEXI
3323 @item -S
3324 @findex -S
3325 Do not start CPU at startup (you must type 'c' in the monitor).
3326 ETEXI
3328 DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3329 "-realtime [mlock=on|off]\n"
3330 " run qemu with realtime features\n"
3331 " mlock=on|off controls mlock support (default: on)\n",
3332 QEMU_ARCH_ALL)
3333 STEXI
3334 @item -realtime mlock=on|off
3335 @findex -realtime
3336 Run qemu with realtime features.
3337 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3338 (enabled by default).
3339 ETEXI
3341 DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit,
3342 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n"
3343 " run qemu with overcommit hints\n"
3344 " mem-lock=on|off controls memory lock support (default: off)\n"
3345 " cpu-pm=on|off controls cpu power management (default: off)\n",
3346 QEMU_ARCH_ALL)
3347 STEXI
3348 @item -overcommit mem-lock=on|off
3349 @item -overcommit cpu-pm=on|off
3350 @findex -overcommit
3351 Run qemu with hints about host resource overcommit. The default is
3352 to assume that host overcommits all resources.
3354 Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled
3355 by default). This works when host memory is not overcommitted and reduces the
3356 worst-case latency for guest. This is equivalent to @option{realtime}.
3358 Guest ability to manage power state of host cpus (increasing latency for other
3359 processes on the same host cpu, but decreasing latency for guest) can be
3360 enabled via @option{cpu-pm=on} (disabled by default). This works best when
3361 host CPU is not overcommitted. When used, host estimates of CPU cycle and power
3362 utilization will be incorrect, not taking into account guest idle time.
3363 ETEXI
3365 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3366 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3367 STEXI
3368 @item -gdb @var{dev}
3369 @findex -gdb
3370 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3371 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3372 stdio are reasonable use case. The latter is allowing to start QEMU from
3373 within gdb and establish the connection via a pipe:
3374 @example
3375 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3376 @end example
3377 ETEXI
3379 DEF("s", 0, QEMU_OPTION_s, \
3380 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3381 QEMU_ARCH_ALL)
3382 STEXI
3383 @item -s
3384 @findex -s
3385 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3386 (@pxref{gdb_usage}).
3387 ETEXI
3389 DEF("d", HAS_ARG, QEMU_OPTION_d, \
3390 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
3391 QEMU_ARCH_ALL)
3392 STEXI
3393 @item -d @var{item1}[,...]
3394 @findex -d
3395 Enable logging of specified items. Use '-d help' for a list of log items.
3396 ETEXI
3398 DEF("D", HAS_ARG, QEMU_OPTION_D, \
3399 "-D logfile output log to logfile (default stderr)\n",
3400 QEMU_ARCH_ALL)
3401 STEXI
3402 @item -D @var{logfile}
3403 @findex -D
3404 Output log in @var{logfile} instead of to stderr
3405 ETEXI
3407 DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3408 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3409 QEMU_ARCH_ALL)
3410 STEXI
3411 @item -dfilter @var{range1}[,...]
3412 @findex -dfilter
3413 Filter debug output to that relevant to a range of target addresses. The filter
3414 spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3415 @var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3416 addresses and sizes required. For example:
3417 @example
3418 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3419 @end example
3420 Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3421 the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3422 block starting at 0xffffffc00005f000.
3423 ETEXI
3425 DEF("L", HAS_ARG, QEMU_OPTION_L, \
3426 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
3427 QEMU_ARCH_ALL)
3428 STEXI
3429 @item -L @var{path}
3430 @findex -L
3431 Set the directory for the BIOS, VGA BIOS and keymaps.
3433 To list all the data directories, use @code{-L help}.
3434 ETEXI
3436 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3437 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
3438 STEXI
3439 @item -bios @var{file}
3440 @findex -bios
3441 Set the filename for the BIOS.
3442 ETEXI
3444 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3445 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3446 STEXI
3447 @item -enable-kvm
3448 @findex -enable-kvm
3449 Enable KVM full virtualization support. This option is only available
3450 if KVM support is enabled when compiling.
3451 ETEXI
3453 DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3454 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386)
3455 STEXI
3456 @item -enable-hax
3457 @findex -enable-hax
3458 Enable HAX (Hardware-based Acceleration eXecution) support. This option
3459 is only available if HAX support is enabled when compiling. HAX is only
3460 applicable to MAC and Windows platform, and thus does not conflict with
3461 KVM. This option is deprecated, use @option{-accel hax} instead.
3462 ETEXI
3464 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3465 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
3466 DEF("xen-create", 0, QEMU_OPTION_xen_create,
3467 "-xen-create create domain using xen hypercalls, bypassing xend\n"
3468 " warning: should not be used when xend is in use\n",
3469 QEMU_ARCH_ALL)
3470 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3471 "-xen-attach attach to existing xen domain\n"
3472 " xend will use this when starting QEMU\n",
3473 QEMU_ARCH_ALL)
3474 DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
3475 "-xen-domid-restrict restrict set of available xen operations\n"
3476 " to specified domain id. (Does not affect\n"
3477 " xenpv machine type).\n",
3478 QEMU_ARCH_ALL)
3479 STEXI
3480 @item -xen-domid @var{id}
3481 @findex -xen-domid
3482 Specify xen guest domain @var{id} (XEN only).
3483 @item -xen-create
3484 @findex -xen-create
3485 Create domain using xen hypercalls, bypassing xend.
3486 Warning: should not be used when xend is in use (XEN only).
3487 @item -xen-attach
3488 @findex -xen-attach
3489 Attach to existing xen domain.
3490 xend will use this when starting QEMU (XEN only).
3491 @findex -xen-domid-restrict
3492 Restrict set of available xen operations to specified domain id (XEN only).
3493 ETEXI
3495 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3496 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
3497 STEXI
3498 @item -no-reboot
3499 @findex -no-reboot
3500 Exit instead of rebooting.
3501 ETEXI
3503 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3504 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
3505 STEXI
3506 @item -no-shutdown
3507 @findex -no-shutdown
3508 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3509 This allows for instance switching to monitor to commit changes to the
3510 disk image.
3511 ETEXI
3513 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3514 "-loadvm [tag|id]\n" \
3515 " start right away with a saved state (loadvm in monitor)\n",
3516 QEMU_ARCH_ALL)
3517 STEXI
3518 @item -loadvm @var{file}
3519 @findex -loadvm
3520 Start right away with a saved state (@code{loadvm} in monitor)
3521 ETEXI
3523 #ifndef _WIN32
3524 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3525 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3526 #endif
3527 STEXI
3528 @item -daemonize
3529 @findex -daemonize
3530 Daemonize the QEMU process after initialization. QEMU will not detach from
3531 standard IO until it is ready to receive connections on any of its devices.
3532 This option is a useful way for external programs to launch QEMU without having
3533 to cope with initialization race conditions.
3534 ETEXI
3536 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3537 "-option-rom rom load a file, rom, into the option ROM space\n",
3538 QEMU_ARCH_ALL)
3539 STEXI
3540 @item -option-rom @var{file}
3541 @findex -option-rom
3542 Load the contents of @var{file} as an option ROM.
3543 This option is useful to load things like EtherBoot.
3544 ETEXI
3546 HXCOMM Silently ignored for compatibility
3547 DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3549 HXCOMM Options deprecated by -rtc
3550 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3551 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3553 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3554 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3555 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3556 QEMU_ARCH_ALL)
3558 STEXI
3560 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3561 @findex -rtc
3562 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3563 UTC or local time, respectively. @code{localtime} is required for correct date in
3564 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3565 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3567 By default the RTC is driven by the host system time. This allows using of the
3568 RTC as accurate reference clock inside the guest, specifically if the host
3569 time is smoothly following an accurate external reference clock, e.g. via NTP.
3570 If you want to isolate the guest time from the host, you can set @option{clock}
3571 to @code{rt} instead. To even prevent it from progressing during suspension,
3572 you can set it to @code{vm}.
3574 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3575 specifically with Windows' ACPI HAL. This option will try to figure out how
3576 many timer interrupts were not processed by the Windows guest and will
3577 re-inject them.
3578 ETEXI
3580 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3581 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3582 " enable virtual instruction counter with 2^N clock ticks per\n" \
3583 " instruction, enable aligning the host and virtual clocks\n" \
3584 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3585 STEXI
3586 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3587 @findex -icount
3588 Enable virtual instruction counter. The virtual cpu will execute one
3589 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3590 then the virtual cpu speed will be automatically adjusted to keep virtual
3591 time within a few seconds of real time.
3593 When the virtual cpu is sleeping, the virtual time will advance at default
3594 speed unless @option{sleep=on|off} is specified.
3595 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3596 instantly whenever the virtual cpu goes to sleep mode and will not advance
3597 if no timer is enabled. This behavior give deterministic execution times from
3598 the guest point of view.
3600 Note that while this option can give deterministic behavior, it does not
3601 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3602 order cores with complex cache hierarchies. The number of instructions
3603 executed often has little or no correlation with actual performance.
3605 @option{align=on} will activate the delay algorithm which will try
3606 to synchronise the host clock and the virtual clock. The goal is to
3607 have a guest running at the real frequency imposed by the shift option.
3608 Whenever the guest clock is behind the host clock and if
3609 @option{align=on} is specified then we print a message to the user
3610 to inform about the delay.
3611 Currently this option does not work when @option{shift} is @code{auto}.
3612 Note: The sync algorithm will work for those shift values for which
3613 the guest clock runs ahead of the host clock. Typically this happens
3614 when the shift value is high (how high depends on the host machine).
3616 When @option{rr} option is specified deterministic record/replay is enabled.
3617 Replay log is written into @var{filename} file in record mode and
3618 read from this file in replay mode.
3620 Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3621 at the start of execution recording. In replay mode this option is used
3622 to load the initial VM state.
3623 ETEXI
3625 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3626 "-watchdog model\n" \
3627 " enable virtual hardware watchdog [default=none]\n",
3628 QEMU_ARCH_ALL)
3629 STEXI
3630 @item -watchdog @var{model}
3631 @findex -watchdog
3632 Create a virtual hardware watchdog device. Once enabled (by a guest
3633 action), the watchdog must be periodically polled by an agent inside
3634 the guest or else the guest will be restarted. Choose a model for
3635 which your guest has drivers.
3637 The @var{model} is the model of hardware watchdog to emulate. Use
3638 @code{-watchdog help} to list available hardware models. Only one
3639 watchdog can be enabled for a guest.
3641 The following models may be available:
3642 @table @option
3643 @item ib700
3644 iBASE 700 is a very simple ISA watchdog with a single timer.
3645 @item i6300esb
3646 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3647 dual-timer watchdog.
3648 @item diag288
3649 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3650 (currently KVM only).
3651 @end table
3652 ETEXI
3654 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3655 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \
3656 " action when watchdog fires [default=reset]\n",
3657 QEMU_ARCH_ALL)
3658 STEXI
3659 @item -watchdog-action @var{action}
3660 @findex -watchdog-action
3662 The @var{action} controls what QEMU will do when the watchdog timer
3663 expires.
3664 The default is
3665 @code{reset} (forcefully reset the guest).
3666 Other possible actions are:
3667 @code{shutdown} (attempt to gracefully shutdown the guest),
3668 @code{poweroff} (forcefully poweroff the guest),
3669 @code{inject-nmi} (inject a NMI into the guest),
3670 @code{pause} (pause the guest),
3671 @code{debug} (print a debug message and continue), or
3672 @code{none} (do nothing).
3674 Note that the @code{shutdown} action requires that the guest responds
3675 to ACPI signals, which it may not be able to do in the sort of
3676 situations where the watchdog would have expired, and thus
3677 @code{-watchdog-action shutdown} is not recommended for production use.
3679 Examples:
3681 @table @code
3682 @item -watchdog i6300esb -watchdog-action pause
3683 @itemx -watchdog ib700
3684 @end table
3685 ETEXI
3687 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3688 "-echr chr set terminal escape character instead of ctrl-a\n",
3689 QEMU_ARCH_ALL)
3690 STEXI
3692 @item -echr @var{numeric_ascii_value}
3693 @findex -echr
3694 Change the escape character used for switching to the monitor when using
3695 monitor and serial sharing. The default is @code{0x01} when using the
3696 @code{-nographic} option. @code{0x01} is equal to pressing
3697 @code{Control-a}. You can select a different character from the ascii
3698 control keys where 1 through 26 map to Control-a through Control-z. For
3699 instance you could use the either of the following to change the escape
3700 character to Control-t.
3701 @table @code
3702 @item -echr 0x14
3703 @itemx -echr 20
3704 @end table
3705 ETEXI
3707 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3708 "-virtioconsole c\n" \
3709 " set virtio console\n", QEMU_ARCH_ALL)
3710 STEXI
3711 @item -virtioconsole @var{c}
3712 @findex -virtioconsole
3713 Set virtio console.
3714 This option is deprecated, please use @option{-device virtconsole} instead.
3715 ETEXI
3717 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3718 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3719 STEXI
3720 @item -show-cursor
3721 @findex -show-cursor
3722 Show cursor.
3723 ETEXI
3725 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3726 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3727 STEXI
3728 @item -tb-size @var{n}
3729 @findex -tb-size
3730 Set TB size.
3731 ETEXI
3733 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3734 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3735 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3736 "-incoming unix:socketpath\n" \
3737 " prepare for incoming migration, listen on\n" \
3738 " specified protocol and socket address\n" \
3739 "-incoming fd:fd\n" \
3740 "-incoming exec:cmdline\n" \
3741 " accept incoming migration on given file descriptor\n" \
3742 " or from given external command\n" \
3743 "-incoming defer\n" \
3744 " wait for the URI to be specified via migrate_incoming\n",
3745 QEMU_ARCH_ALL)
3746 STEXI
3747 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3748 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3749 @findex -incoming
3750 Prepare for incoming migration, listen on a given tcp port.
3752 @item -incoming unix:@var{socketpath}
3753 Prepare for incoming migration, listen on a given unix socket.
3755 @item -incoming fd:@var{fd}
3756 Accept incoming migration from a given filedescriptor.
3758 @item -incoming exec:@var{cmdline}
3759 Accept incoming migration as an output from specified external command.
3761 @item -incoming defer
3762 Wait for the URI to be specified via migrate_incoming. The monitor can
3763 be used to change settings (such as migration parameters) prior to issuing
3764 the migrate_incoming to allow the migration to begin.
3765 ETEXI
3767 DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \
3768 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL)
3769 STEXI
3770 @item -only-migratable
3771 @findex -only-migratable
3772 Only allow migratable devices. Devices will not be allowed to enter an
3773 unmigratable state.
3774 ETEXI
3776 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3777 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
3778 STEXI
3779 @item -nodefaults
3780 @findex -nodefaults
3781 Don't create default devices. Normally, QEMU sets the default devices like serial
3782 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3783 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3784 default devices.
3785 ETEXI
3787 #ifndef _WIN32
3788 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3789 "-chroot dir chroot to dir just before starting the VM\n",
3790 QEMU_ARCH_ALL)
3791 #endif
3792 STEXI
3793 @item -chroot @var{dir}
3794 @findex -chroot
3795 Immediately before starting guest execution, chroot to the specified
3796 directory. Especially useful in combination with -runas.
3797 ETEXI
3799 #ifndef _WIN32
3800 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3801 "-runas user change to user id user just before starting the VM\n" \
3802 " user can be numeric uid:gid instead\n",
3803 QEMU_ARCH_ALL)
3804 #endif
3805 STEXI
3806 @item -runas @var{user}
3807 @findex -runas
3808 Immediately before starting guest execution, drop root privileges, switching
3809 to the specified user.
3810 ETEXI
3812 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3813 "-prom-env variable=value\n"
3814 " set OpenBIOS nvram variables\n",
3815 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3816 STEXI
3817 @item -prom-env @var{variable}=@var{value}
3818 @findex -prom-env
3819 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3820 ETEXI
3821 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3822 "-semihosting semihosting mode\n",
3823 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3824 QEMU_ARCH_MIPS)
3825 STEXI
3826 @item -semihosting
3827 @findex -semihosting
3828 Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3829 ETEXI
3830 DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3831 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3832 " semihosting configuration\n",
3833 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3834 QEMU_ARCH_MIPS)
3835 STEXI
3836 @item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3837 @findex -semihosting-config
3838 Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3839 @table @option
3840 @item target=@code{native|gdb|auto}
3841 Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3842 or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3843 during debug sessions and @code{native} otherwise.
3844 @item arg=@var{str1},arg=@var{str2},...
3845 Allows the user to pass input arguments, and can be used multiple times to build
3846 up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3847 command line is still supported for backward compatibility. If both the
3848 @code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3849 specified, the former is passed to semihosting as it always takes precedence.
3850 @end table
3851 ETEXI
3852 DEF("old-param", 0, QEMU_OPTION_old_param,
3853 "-old-param old param mode\n", QEMU_ARCH_ARM)
3854 STEXI
3855 @item -old-param
3856 @findex -old-param (ARM)
3857 Old param mode (ARM only).
3858 ETEXI
3860 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3861 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
3862 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
3863 " Enable seccomp mode 2 system call filter (default 'off').\n" \
3864 " use 'obsolete' to allow obsolete system calls that are provided\n" \
3865 " by the kernel, but typically no longer used by modern\n" \
3866 " C library implementations.\n" \
3867 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \
3868 " its privileges by blacklisting all set*uid|gid system calls.\n" \
3869 " The value 'children' will deny set*uid|gid system calls for\n" \
3870 " main QEMU process but will allow forks and execves to run unprivileged\n" \
3871 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \
3872 " blacklisting *fork and execve\n" \
3873 " use 'resourcecontrol' to disable process affinity and schedular priority\n",
3874 QEMU_ARCH_ALL)
3875 STEXI
3876 @item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
3877 @findex -sandbox
3878 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3879 disable it. The default is 'off'.
3880 @table @option
3881 @item obsolete=@var{string}
3882 Enable Obsolete system calls
3883 @item elevateprivileges=@var{string}
3884 Disable set*uid|gid system calls
3885 @item spawn=@var{string}
3886 Disable *fork and execve
3887 @item resourcecontrol=@var{string}
3888 Disable process affinity and schedular priority
3889 @end table
3890 ETEXI
3892 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3893 "-readconfig <file>\n", QEMU_ARCH_ALL)
3894 STEXI
3895 @item -readconfig @var{file}
3896 @findex -readconfig
3897 Read device configuration from @var{file}. This approach is useful when you want to spawn
3898 QEMU process with many command line options but you don't want to exceed the command line
3899 character limit.
3900 ETEXI
3901 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3902 "-writeconfig <file>\n"
3903 " read/write config file\n", QEMU_ARCH_ALL)
3904 STEXI
3905 @item -writeconfig @var{file}
3906 @findex -writeconfig
3907 Write device configuration to @var{file}. The @var{file} can be either filename to save
3908 command line and device configuration into file or dash @code{-}) character to print the
3909 output to stdout. This can be later used as input file for @code{-readconfig} option.
3910 ETEXI
3911 HXCOMM Deprecated, same as -no-user-config
3912 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
3913 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3914 "-no-user-config\n"
3915 " do not load default user-provided config files at startup\n",
3916 QEMU_ARCH_ALL)
3917 STEXI
3918 @item -no-user-config
3919 @findex -no-user-config
3920 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3921 config files on @var{sysconfdir}.
3922 ETEXI
3923 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3924 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3925 " specify tracing options\n",
3926 QEMU_ARCH_ALL)
3927 STEXI
3928 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3929 HXCOMM HX does not support conditional compilation of text.
3930 @item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
3931 @findex -trace
3932 @include qemu-option-trace.texi
3933 ETEXI
3935 HXCOMM Internal use
3936 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3937 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3939 #ifdef __linux__
3940 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3941 "-enable-fips enable FIPS 140-2 compliance\n",
3942 QEMU_ARCH_ALL)
3943 #endif
3944 STEXI
3945 @item -enable-fips
3946 @findex -enable-fips
3947 Enable FIPS 140-2 compliance mode.
3948 ETEXI
3950 HXCOMM Deprecated by -machine accel=tcg property
3951 DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3953 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3954 "-msg timestamp[=on|off]\n"
3955 " change the format of messages\n"
3956 " on|off controls leading timestamps (default:on)\n",
3957 QEMU_ARCH_ALL)
3958 STEXI
3959 @item -msg timestamp[=on|off]
3960 @findex -msg
3961 prepend a timestamp to each log message.(default:on)
3962 ETEXI
3964 DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3965 "-dump-vmstate <file>\n"
3966 " Output vmstate information in JSON format to file.\n"
3967 " Use the scripts/vmstate-static-checker.py file to\n"
3968 " check for possible regressions in migration code\n"
3969 " by comparing two such vmstate dumps.\n",
3970 QEMU_ARCH_ALL)
3971 STEXI
3972 @item -dump-vmstate @var{file}
3973 @findex -dump-vmstate
3974 Dump json-encoded vmstate information for current machine type to file
3975 in @var{file}
3976 ETEXI
3978 STEXI
3979 @end table
3980 ETEXI
3981 DEFHEADING()
3983 DEFHEADING(Generic object creation:)
3984 STEXI
3985 @table @option
3986 ETEXI
3988 DEF("object", HAS_ARG, QEMU_OPTION_object,
3989 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3990 " create a new object of type TYPENAME setting properties\n"
3991 " in the order they are specified. Note that the 'id'\n"
3992 " property must be set. These objects are placed in the\n"
3993 " '/objects' path.\n",
3994 QEMU_ARCH_ALL)
3995 STEXI
3996 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3997 @findex -object
3998 Create a new object of type @var{typename} setting properties
3999 in the order they are specified. Note that the 'id'
4000 property must be set. These objects are placed in the
4001 '/objects' path.
4003 @table @option
4005 @item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off},discard-data=@var{on|off},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},align=@var{align}
4007 Creates a memory file backend object, which can be used to back
4008 the guest RAM with huge pages.
4010 The @option{id} parameter is a unique ID that will be used to reference this
4011 memory region when configuring the @option{-numa} argument.
4013 The @option{size} option provides the size of the memory region, and accepts
4014 common suffixes, eg @option{500M}.
4016 The @option{mem-path} provides the path to either a shared memory or huge page
4017 filesystem mount.
4019 The @option{share} boolean option determines whether the memory
4020 region is marked as private to QEMU, or shared. The latter allows
4021 a co-operating external process to access the QEMU memory region.
4023 The @option{share} is also required for pvrdma devices due to
4024 limitations in the RDMA API provided by Linux.
4026 Setting share=on might affect the ability to configure NUMA
4027 bindings for the memory backend under some circumstances, see
4028 Documentation/vm/numa_memory_policy.txt on the Linux kernel
4029 source tree for additional details.
4031 Setting the @option{discard-data} boolean option to @var{on}
4032 indicates that file contents can be destroyed when QEMU exits,
4033 to avoid unnecessarily flushing data to the backing file. Note
4034 that @option{discard-data} is only an optimization, and QEMU
4035 might not discard file contents if it aborts unexpectedly or is
4036 terminated using SIGKILL.
4038 The @option{merge} boolean option enables memory merge, also known as
4039 MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for
4040 memory deduplication.
4042 Setting the @option{dump} boolean option to @var{off} excludes the memory from
4043 core dumps. This feature is also known as MADV_DONTDUMP.
4045 The @option{prealloc} boolean option enables memory preallocation.
4047 The @option{host-nodes} option binds the memory range to a list of NUMA host
4048 nodes.
4050 The @option{policy} option sets the NUMA policy to one of the following values:
4052 @table @option
4053 @item @var{default}
4054 default host policy
4056 @item @var{preferred}
4057 prefer the given host node list for allocation
4059 @item @var{bind}
4060 restrict memory allocation to the given host node list
4062 @item @var{interleave}
4063 interleave memory allocations across the given host node list
4064 @end table
4066 The @option{align} option specifies the base address alignment when
4067 QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg
4068 @option{2M}. Some backend store specified by @option{mem-path}
4069 requires an alignment different than the default one used by QEMU, eg
4070 the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In
4071 such cases, users can specify the required alignment via this option.
4073 @item -object memory-backend-ram,id=@var{id},merge=@var{on|off},dump=@var{on|off},share=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave}
4075 Creates a memory backend object, which can be used to back the guest RAM.
4076 Memory backend objects offer more control than the @option{-m} option that is
4077 traditionally used to define guest RAM. Please refer to
4078 @option{memory-backend-file} for a description of the options.
4080 @item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size}
4082 Creates an anonymous memory file backend object, which allows QEMU to
4083 share the memory with an external process (e.g. when using
4084 vhost-user). The memory is allocated with memfd and optional
4085 sealing. (Linux only)
4087 The @option{seal} option creates a sealed-file, that will block
4088 further resizing the memory ('on' by default).
4090 The @option{hugetlb} option specify the file to be created resides in
4091 the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with
4092 the @option{hugetlb} option, the @option{hugetlbsize} option specify
4093 the hugetlb page size on systems that support multiple hugetlb page
4094 sizes (it must be a power of 2 value supported by the system).
4096 In some versions of Linux, the @option{hugetlb} option is incompatible
4097 with the @option{seal} option (requires at least Linux 4.16).
4099 Please refer to @option{memory-backend-file} for a description of the
4100 other options.
4102 @item -object rng-random,id=@var{id},filename=@var{/dev/random}
4104 Creates a random number generator backend which obtains entropy from
4105 a device on the host. The @option{id} parameter is a unique ID that
4106 will be used to reference this entropy backend from the @option{virtio-rng}
4107 device. The @option{filename} parameter specifies which file to obtain
4108 entropy from and if omitted defaults to @option{/dev/random}.
4110 @item -object rng-egd,id=@var{id},chardev=@var{chardevid}
4112 Creates a random number generator backend which obtains entropy from
4113 an external daemon running on the host. The @option{id} parameter is
4114 a unique ID that will be used to reference this entropy backend from
4115 the @option{virtio-rng} device. The @option{chardev} parameter is
4116 the unique ID of a character device backend that provides the connection
4117 to the RNG daemon.
4119 @item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
4121 Creates a TLS anonymous credentials object, which can be used to provide
4122 TLS support on network backends. The @option{id} parameter is a unique
4123 ID which network backends will use to access the credentials. The
4124 @option{endpoint} is either @option{server} or @option{client} depending
4125 on whether the QEMU network backend that uses the credentials will be
4126 acting as a client or as a server. If @option{verify-peer} is enabled
4127 (the default) then once the handshake is completed, the peer credentials
4128 will be verified, though this is a no-op for anonymous credentials.
4130 The @var{dir} parameter tells QEMU where to find the credential
4131 files. For server endpoints, this directory may contain a file
4132 @var{dh-params.pem} providing diffie-hellman parameters to use
4133 for the TLS server. If the file is missing, QEMU will generate
4134 a set of DH parameters at startup. This is a computationally
4135 expensive operation that consumes random pool entropy, so it is
4136 recommended that a persistent set of parameters be generated
4137 upfront and saved.
4139 @item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}]
4141 Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide
4142 TLS support on network backends. The @option{id} parameter is a unique
4143 ID which network backends will use to access the credentials. The
4144 @option{endpoint} is either @option{server} or @option{client} depending
4145 on whether the QEMU network backend that uses the credentials will be
4146 acting as a client or as a server. For clients only, @option{username}
4147 is the username which will be sent to the server. If omitted
4148 it defaults to ``qemu''.
4150 The @var{dir} parameter tells QEMU where to find the keys file.
4151 It is called ``@var{dir}/keys.psk'' and contains ``username:key''
4152 pairs. This file can most easily be created using the GnuTLS
4153 @code{psktool} program.
4155 For server endpoints, @var{dir} may also contain a file
4156 @var{dh-params.pem} providing diffie-hellman parameters to use
4157 for the TLS server. If the file is missing, QEMU will generate
4158 a set of DH parameters at startup. This is a computationally
4159 expensive operation that consumes random pool entropy, so it is
4160 recommended that a persistent set of parameters be generated
4161 up front and saved.
4163 @item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},priority=@var{priority},verify-peer=@var{on|off},passwordid=@var{id}
4165 Creates a TLS anonymous credentials object, which can be used to provide
4166 TLS support on network backends. The @option{id} parameter is a unique
4167 ID which network backends will use to access the credentials. The
4168 @option{endpoint} is either @option{server} or @option{client} depending
4169 on whether the QEMU network backend that uses the credentials will be
4170 acting as a client or as a server. If @option{verify-peer} is enabled
4171 (the default) then once the handshake is completed, the peer credentials
4172 will be verified. With x509 certificates, this implies that the clients
4173 must be provided with valid client certificates too.
4175 The @var{dir} parameter tells QEMU where to find the credential
4176 files. For server endpoints, this directory may contain a file
4177 @var{dh-params.pem} providing diffie-hellman parameters to use
4178 for the TLS server. If the file is missing, QEMU will generate
4179 a set of DH parameters at startup. This is a computationally
4180 expensive operation that consumes random pool entropy, so it is
4181 recommended that a persistent set of parameters be generated
4182 upfront and saved.
4184 For x509 certificate credentials the directory will contain further files
4185 providing the x509 certificates. The certificates must be stored
4186 in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
4187 @var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
4188 @var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
4190 For the @var{server-key.pem} and @var{client-key.pem} files which
4191 contain sensitive private keys, it is possible to use an encrypted
4192 version by providing the @var{passwordid} parameter. This provides
4193 the ID of a previously created @code{secret} object containing the
4194 password for decryption.
4196 The @var{priority} parameter allows to override the global default
4197 priority used by gnutls. This can be useful if the system administrator
4198 needs to use a weaker set of crypto priorities for QEMU without
4199 potentially forcing the weakness onto all applications. Or conversely
4200 if one wants wants a stronger default for QEMU than for all other
4201 applications, they can do this through this parameter. Its format is
4202 a gnutls priority string as described at
4203 @url{https://gnutls.org/manual/html_node/Priority-Strings.html}.
4205 @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
4207 Interval @var{t} can't be 0, this filter batches the packet delivery: all
4208 packets arriving in a given interval on netdev @var{netdevid} are delayed
4209 until the end of the interval. Interval is in microseconds.
4210 @option{status} is optional that indicate whether the netfilter is
4211 on (enabled) or off (disabled), the default status for netfilter will be 'on'.
4213 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4215 @option{all}: the filter is attached both to the receive and the transmit
4216 queue of the netdev (default).
4218 @option{rx}: the filter is attached to the receive queue of the netdev,
4219 where it will receive packets sent to the netdev.
4221 @option{tx}: the filter is attached to the transmit queue of the netdev,
4222 where it will receive packets sent by the netdev.
4224 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4226 filter-mirror on netdev @var{netdevid},mirror net packet to chardev@var{chardevid}, if it has the vnet_hdr_support flag, filter-mirror will mirror packet with vnet_hdr_len.
4228 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4230 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4231 @var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
4232 filter-redirector will redirect packet with vnet_hdr_len.
4233 Create a filter-redirector we need to differ outdev id from indev id, id can not
4234 be the same. we can just use indev or outdev, but at least one of indev or outdev
4235 need to be specified.
4237 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4239 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4240 secondary from primary to keep secondary tcp connection,and rewrite
4241 tcp packet to primary from secondary make tcp packet can be handled by
4242 client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4244 usage:
4245 colo secondary:
4246 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4247 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4248 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
4250 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4252 Dump the network traffic on netdev @var{dev} to the file specified by
4253 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4254 The file format is libpcap, so it can be analyzed with tools such as tcpdump
4255 or Wireshark.
4257 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4259 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4260 secondary packet. If the packets are same, we will output primary
4261 packet to outdev@var{chardevid}, else we will notify colo-frame
4262 do checkpoint and send primary packet to outdev@var{chardevid}.
4263 if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4265 we must use it with the help of filter-mirror and filter-redirector.
4267 @example
4269 primary:
4270 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4271 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4272 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4273 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4274 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4275 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4276 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4277 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4278 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4279 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4280 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4281 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4283 secondary:
4284 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4285 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4286 -chardev socket,id=red0,host=3.3.3.3,port=9003
4287 -chardev socket,id=red1,host=3.3.3.3,port=9004
4288 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4289 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4291 @end example
4293 If you want to know the detail of above command line, you can read
4294 the colo-compare git log.
4296 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4298 Creates a cryptodev backend which executes crypto opreation from
4299 the QEMU cipher APIS. The @var{id} parameter is
4300 a unique ID that will be used to reference this cryptodev backend from
4301 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4302 which specify the queue number of cryptodev backend, the default of
4303 @var{queues} is 1.
4305 @example
4307 # qemu-system-x86_64 \
4308 [...] \
4309 -object cryptodev-backend-builtin,id=cryptodev0 \
4310 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4311 [...]
4312 @end example
4314 @item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}]
4316 Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}.
4317 The @var{id} parameter is a unique ID that will be used to reference this
4318 cryptodev backend from the @option{virtio-crypto} device.
4319 The chardev should be a unix domain socket backed one. The vhost-user uses
4320 a specifically defined protocol to pass vhost ioctl replacement messages
4321 to an application on the other end of the socket.
4322 The @var{queues} parameter is optional, which specify the queue number
4323 of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1.
4325 @example
4327 # qemu-system-x86_64 \
4328 [...] \
4329 -chardev socket,id=chardev0,path=/path/to/socket \
4330 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \
4331 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4332 [...]
4333 @end example
4335 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4336 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4338 Defines a secret to store a password, encryption key, or some other sensitive
4339 data. The sensitive data can either be passed directly via the @var{data}
4340 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4341 parameter is insecure unless the sensitive data is encrypted.
4343 The sensitive data can be provided in raw format (the default), or base64.
4344 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4345 so base64 is recommended for sending binary data. QEMU will convert from
4346 which ever format is provided to the format it needs internally. eg, an
4347 RBD password can be provided in raw format, even though it will be base64
4348 encoded when passed onto the RBD sever.
4350 For added protection, it is possible to encrypt the data associated with
4351 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4352 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4353 parameter provides the ID of a previously defined secret that contains
4354 the AES-256 decryption key. This key should be 32-bytes long and be
4355 base64 encoded. The @var{iv} parameter provides the random initialization
4356 vector used for encryption of this particular secret and should be a
4357 base64 encrypted string of the 16-byte IV.
4359 The simplest (insecure) usage is to provide the secret inline
4361 @example
4363 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4365 @end example
4367 The simplest secure usage is to provide the secret via a file
4369 # printf "letmein" > mypasswd.txt
4370 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4372 For greater security, AES-256-CBC should be used. To illustrate usage,
4373 consider the openssl command line tool which can encrypt the data. Note
4374 that when encrypting, the plaintext must be padded to the cipher block
4375 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4377 First a master key needs to be created in base64 encoding:
4379 @example
4380 # openssl rand -base64 32 > key.b64
4381 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
4382 @end example
4384 Each secret to be encrypted needs to have a random initialization vector
4385 generated. These do not need to be kept secret
4387 @example
4388 # openssl rand -base64 16 > iv.b64
4389 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
4390 @end example
4392 The secret to be defined can now be encrypted, in this case we're
4393 telling openssl to base64 encode the result, but it could be left
4394 as raw bytes if desired.
4396 @example
4397 # SECRET=$(printf "letmein" |
4398 openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4399 @end example
4401 When launching QEMU, create a master secret pointing to @code{key.b64}
4402 and specify that to be used to decrypt the user password. Pass the
4403 contents of @code{iv.b64} to the second secret
4405 @example
4406 # $QEMU \
4407 -object secret,id=secmaster0,format=base64,file=key.b64 \
4408 -object secret,id=sec0,keyid=secmaster0,format=base64,\
4409 data=$SECRET,iv=$(<iv.b64)
4410 @end example
4412 @item -object sev-guest,id=@var{id},cbitpos=@var{cbitpos},reduced-phys-bits=@var{val},[sev-device=@var{string},policy=@var{policy},handle=@var{handle},dh-cert-file=@var{file},session-file=@var{file}]
4414 Create a Secure Encrypted Virtualization (SEV) guest object, which can be used
4415 to provide the guest memory encryption support on AMD processors.
4417 When memory encryption is enabled, one of the physical address bit (aka the
4418 C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos}
4419 is used to provide the C-bit position. The C-bit position is Host family dependent
4420 hence user must provide this value. On EPYC, the value should be 47.
4422 When memory encryption is enabled, we loose certain bits in physical address space.
4423 The @option{reduced-phys-bits} is used to provide the number of bits we loose in
4424 physical address space. Similar to C-bit, the value is Host family dependent.
4425 On EPYC, the value should be 5.
4427 The @option{sev-device} provides the device file to use for communicating with
4428 the SEV firmware running inside AMD Secure Processor. The default device is
4429 '/dev/sev'. If hardware supports memory encryption then /dev/sev devices are
4430 created by CCP driver.
4432 The @option{policy} provides the guest policy to be enforced by the SEV firmware
4433 and restrict what configuration and operational commands can be performed on this
4434 guest by the hypervisor. The policy should be provided by the guest owner and is
4435 bound to the guest and cannot be changed throughout the lifetime of the guest.
4436 The default is 0.
4438 If guest @option{policy} allows sharing the key with another SEV guest then
4439 @option{handle} can be use to provide handle of the guest from which to share
4440 the key.
4442 The @option{dh-cert-file} and @option{session-file} provides the guest owner's
4443 Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters
4444 are used for establishing a cryptographic session with the guest owner to
4445 negotiate keys used for attestation. The file must be encoded in base64.
4447 e.g to launch a SEV guest
4448 @example
4449 # $QEMU \
4450 ......
4451 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \
4452 -machine ...,memory-encryption=sev0
4453 .....
4455 @end example
4456 @end table
4458 ETEXI
4461 HXCOMM This is the last statement. Insert new options before this line!
4462 STEXI
4463 @end table
4464 ETEXI