test-hbitmap: Add non-advancing iter_next tests
[qemu.git] / qemu-options.hx
blobd5b0c26e8e5733157e7d5f6a4aa5d6ea34abd487
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)", 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 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
808 " [,snapshot=on|off][,rerror=ignore|stop|report]\n"
809 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
810 " [,readonly=on|off][,copy-on-read=on|off]\n"
811 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
812 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
813 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
814 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
815 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
816 " [[,iops_size=is]]\n"
817 " [[,group=g]]\n"
818 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
819 STEXI
820 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
821 @findex -drive
823 Define a new drive. This includes creating a block driver node (the backend) as
824 well as a guest device, and is mostly a shortcut for defining the corresponding
825 @option{-blockdev} and @option{-device} options.
827 @option{-drive} accepts all options that are accepted by @option{-blockdev}. In
828 addition, it knows the following options:
830 @table @option
831 @item file=@var{file}
832 This option defines which disk image (@pxref{disk_images}) to use with
833 this drive. If the filename contains comma, you must double it
834 (for instance, "file=my,,file" to use file "my,file").
836 Special files such as iSCSI devices can be specified using protocol
837 specific URLs. See the section for "Device URL Syntax" for more information.
838 @item if=@var{interface}
839 This option defines on which type on interface the drive is connected.
840 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
841 @item bus=@var{bus},unit=@var{unit}
842 These options define where is connected the drive by defining the bus number and
843 the unit id.
844 @item index=@var{index}
845 This option defines where is connected the drive by using an index in the list
846 of available connectors of a given interface type.
847 @item media=@var{media}
848 This option defines the type of the media: disk or cdrom.
849 @item snapshot=@var{snapshot}
850 @var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
851 (see @option{-snapshot}).
852 @item cache=@var{cache}
853 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough"
854 and controls how the host cache is used to access block data. This is a
855 shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
856 options (as in @option{-blockdev}), and additionally @option{cache.writeback},
857 which provides a default for the @option{write-cache} option of block guest
858 devices (as in @option{-device}). The modes correspond to the following
859 settings:
861 @c Our texi2pod.pl script doesn't support @multitable, so fall back to using
862 @c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
863 @c and the HTML output.
864 @example
865 @ │ cache.writeback cache.direct cache.no-flush
866 ─────────────┼─────────────────────────────────────────────────
867 writeback │ on off off
868 none │ on on off
869 writethrough │ off off off
870 directsync │ off on off
871 unsafe │ on off on
872 @end example
874 The default mode is @option{cache=writeback}.
876 @item aio=@var{aio}
877 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
878 @item format=@var{format}
879 Specify which disk @var{format} will be used rather than detecting
880 the format. Can be used to specify format=raw to avoid interpreting
881 an untrusted format header.
882 @item werror=@var{action},rerror=@var{action}
883 Specify which @var{action} to take on write and read errors. Valid actions are:
884 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
885 "report" (report the error to the guest), "enospc" (pause QEMU only if the
886 host disk is full; report the error to the guest otherwise).
887 The default setting is @option{werror=enospc} and @option{rerror=report}.
888 @item copy-on-read=@var{copy-on-read}
889 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
890 file sectors into the image file.
891 @item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
892 Specify bandwidth throttling limits in bytes per second, either for all request
893 types or for reads or writes only. Small values can lead to timeouts or hangs
894 inside the guest. A safe minimum for disks is 2 MB/s.
895 @item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
896 Specify bursts in bytes per second, either for all request types or for reads
897 or writes only. Bursts allow the guest I/O to spike above the limit
898 temporarily.
899 @item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
900 Specify request rate limits in requests per second, either for all request
901 types or for reads or writes only.
902 @item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
903 Specify bursts in requests per second, either for all request types or for reads
904 or writes only. Bursts allow the guest I/O to spike above the limit
905 temporarily.
906 @item iops_size=@var{is}
907 Let every @var{is} bytes of a request count as a new request for iops
908 throttling purposes. Use this option to prevent guests from circumventing iops
909 limits by sending fewer but larger requests.
910 @item group=@var{g}
911 Join a throttling quota group with given name @var{g}. All drives that are
912 members of the same group are accounted for together. Use this option to
913 prevent guests from circumventing throttling limits by using many small disks
914 instead of a single larger disk.
915 @end table
917 By default, the @option{cache.writeback=on} mode is used. It will report data
918 writes as completed as soon as the data is present in the host page cache.
919 This is safe as long as your guest OS makes sure to correctly flush disk caches
920 where needed. If your guest OS does not handle volatile disk write caches
921 correctly and your host crashes or loses power, then the guest may experience
922 data corruption.
924 For such guests, you should consider using @option{cache.writeback=off}. This
925 means that the host page cache will be used to read and write data, but write
926 notification will be sent to the guest only after QEMU has made sure to flush
927 each write to the disk. Be aware that this has a major impact on performance.
929 When using the @option{-snapshot} option, unsafe caching is always used.
931 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
932 useful when the backing file is over a slow network. By default copy-on-read
933 is off.
935 Instead of @option{-cdrom} you can use:
936 @example
937 qemu-system-i386 -drive file=file,index=2,media=cdrom
938 @end example
940 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
941 use:
942 @example
943 qemu-system-i386 -drive file=file,index=0,media=disk
944 qemu-system-i386 -drive file=file,index=1,media=disk
945 qemu-system-i386 -drive file=file,index=2,media=disk
946 qemu-system-i386 -drive file=file,index=3,media=disk
947 @end example
949 You can open an image using pre-opened file descriptors from an fd set:
950 @example
951 qemu-system-i386
952 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
953 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
954 -drive file=/dev/fdset/2,index=0,media=disk
955 @end example
957 You can connect a CDROM to the slave of ide0:
958 @example
959 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
960 @end example
962 If you don't specify the "file=" argument, you define an empty drive:
963 @example
964 qemu-system-i386 -drive if=ide,index=1,media=cdrom
965 @end example
967 Instead of @option{-fda}, @option{-fdb}, you can use:
968 @example
969 qemu-system-i386 -drive file=file,index=0,if=floppy
970 qemu-system-i386 -drive file=file,index=1,if=floppy
971 @end example
973 By default, @var{interface} is "ide" and @var{index} is automatically
974 incremented:
975 @example
976 qemu-system-i386 -drive file=a -drive file=b"
977 @end example
978 is interpreted like:
979 @example
980 qemu-system-i386 -hda a -hdb b
981 @end example
982 ETEXI
984 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
985 "-mtdblock file use 'file' as on-board Flash memory image\n",
986 QEMU_ARCH_ALL)
987 STEXI
988 @item -mtdblock @var{file}
989 @findex -mtdblock
990 Use @var{file} as on-board Flash memory image.
991 ETEXI
993 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
994 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
995 STEXI
996 @item -sd @var{file}
997 @findex -sd
998 Use @var{file} as SecureDigital card image.
999 ETEXI
1001 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
1002 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
1003 STEXI
1004 @item -pflash @var{file}
1005 @findex -pflash
1006 Use @var{file} as a parallel flash image.
1007 ETEXI
1009 DEF("snapshot", 0, QEMU_OPTION_snapshot,
1010 "-snapshot write to temporary files instead of disk image files\n",
1011 QEMU_ARCH_ALL)
1012 STEXI
1013 @item -snapshot
1014 @findex -snapshot
1015 Write to temporary files instead of disk image files. In this case,
1016 the raw disk image you use is not written back. You can however force
1017 the write back by pressing @key{C-a s} (@pxref{disk_images}).
1018 ETEXI
1020 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
1021 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1022 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1023 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1024 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1025 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1026 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1027 " [[,throttling.iops-size=is]]\n",
1028 QEMU_ARCH_ALL)
1030 STEXI
1032 @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}]
1033 @findex -fsdev
1034 Define a new file system device. Valid options are:
1035 @table @option
1036 @item @var{fsdriver}
1037 This option specifies the fs driver backend to use.
1038 Currently "local", "handle" and "proxy" file system drivers are supported.
1039 @item id=@var{id}
1040 Specifies identifier for this device
1041 @item path=@var{path}
1042 Specifies the export path for the file system device. Files under
1043 this path will be available to the 9p client on the guest.
1044 @item security_model=@var{security_model}
1045 Specifies the security model to be used for this export path.
1046 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1047 In "passthrough" security model, files are stored using the same
1048 credentials as they are created on the guest. This requires QEMU
1049 to run as root. In "mapped-xattr" security model, some of the file
1050 attributes like uid, gid, mode bits and link target are stored as
1051 file attributes. For "mapped-file" these attributes are stored in the
1052 hidden .virtfs_metadata directory. Directories exported by this security model cannot
1053 interact with other unix tools. "none" security model is same as
1054 passthrough except the sever won't report failures if it fails to
1055 set file attributes like ownership. Security model is mandatory
1056 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1057 security model as a parameter.
1058 @item writeout=@var{writeout}
1059 This is an optional argument. The only supported value is "immediate".
1060 This means that host page cache will be used to read and write data but
1061 write notification will be sent to the guest only when the data has been
1062 reported as written by the storage subsystem.
1063 @item readonly
1064 Enables exporting 9p share as a readonly mount for guests. By default
1065 read-write access is given.
1066 @item socket=@var{socket}
1067 Enables proxy filesystem driver to use passed socket file for communicating
1068 with virtfs-proxy-helper
1069 @item sock_fd=@var{sock_fd}
1070 Enables proxy filesystem driver to use passed socket descriptor for
1071 communicating with virtfs-proxy-helper. Usually a helper like libvirt
1072 will create socketpair and pass one of the fds as sock_fd
1073 @item fmode=@var{fmode}
1074 Specifies the default mode for newly created files on the host. Works only
1075 with security models "mapped-xattr" and "mapped-file".
1076 @item dmode=@var{dmode}
1077 Specifies the default mode for newly created directories on the host. Works
1078 only with security models "mapped-xattr" and "mapped-file".
1079 @end table
1081 -fsdev option is used along with -device driver "virtio-9p-pci".
1082 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
1083 Options for virtio-9p-pci driver are:
1084 @table @option
1085 @item fsdev=@var{id}
1086 Specifies the id value specified along with -fsdev option
1087 @item mount_tag=@var{mount_tag}
1088 Specifies the tag name to be used by the guest to mount this export point
1089 @end table
1091 ETEXI
1093 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
1094 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1095 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1096 QEMU_ARCH_ALL)
1098 STEXI
1100 @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}]
1101 @findex -virtfs
1103 The general form of a Virtual File system pass-through options are:
1104 @table @option
1105 @item @var{fsdriver}
1106 This option specifies the fs driver backend to use.
1107 Currently "local", "handle" and "proxy" file system drivers are supported.
1108 @item id=@var{id}
1109 Specifies identifier for this device
1110 @item path=@var{path}
1111 Specifies the export path for the file system device. Files under
1112 this path will be available to the 9p client on the guest.
1113 @item security_model=@var{security_model}
1114 Specifies the security model to be used for this export path.
1115 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1116 In "passthrough" security model, files are stored using the same
1117 credentials as they are created on the guest. This requires QEMU
1118 to run as root. In "mapped-xattr" security model, some of the file
1119 attributes like uid, gid, mode bits and link target are stored as
1120 file attributes. For "mapped-file" these attributes are stored in the
1121 hidden .virtfs_metadata directory. Directories exported by this security model cannot
1122 interact with other unix tools. "none" security model is same as
1123 passthrough except the sever won't report failures if it fails to
1124 set file attributes like ownership. Security model is mandatory only
1125 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1126 model as a parameter.
1127 @item writeout=@var{writeout}
1128 This is an optional argument. The only supported value is "immediate".
1129 This means that host page cache will be used to read and write data but
1130 write notification will be sent to the guest only when the data has been
1131 reported as written by the storage subsystem.
1132 @item readonly
1133 Enables exporting 9p share as a readonly mount for guests. By default
1134 read-write access is given.
1135 @item socket=@var{socket}
1136 Enables proxy filesystem driver to use passed socket file for
1137 communicating with virtfs-proxy-helper. Usually a helper like libvirt
1138 will create socketpair and pass one of the fds as sock_fd
1139 @item sock_fd
1140 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
1141 descriptor for interfacing with virtfs-proxy-helper
1142 @item fmode=@var{fmode}
1143 Specifies the default mode for newly created files on the host. Works only
1144 with security models "mapped-xattr" and "mapped-file".
1145 @item dmode=@var{dmode}
1146 Specifies the default mode for newly created directories on the host. Works
1147 only with security models "mapped-xattr" and "mapped-file".
1148 @end table
1149 ETEXI
1151 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
1152 "-virtfs_synth Create synthetic file system image\n",
1153 QEMU_ARCH_ALL)
1154 STEXI
1155 @item -virtfs_synth
1156 @findex -virtfs_synth
1157 Create synthetic file system image
1158 ETEXI
1160 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
1161 "-iscsi [user=user][,password=password]\n"
1162 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1163 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
1164 " [,timeout=timeout]\n"
1165 " iSCSI session parameters\n", QEMU_ARCH_ALL)
1167 STEXI
1168 @item -iscsi
1169 @findex -iscsi
1170 Configure iSCSI session parameters.
1171 ETEXI
1173 STEXI
1174 @end table
1175 ETEXI
1176 DEFHEADING()
1178 DEFHEADING(USB options:)
1179 STEXI
1180 @table @option
1181 ETEXI
1183 DEF("usb", 0, QEMU_OPTION_usb,
1184 "-usb enable the USB driver (if it is not used by default yet)\n",
1185 QEMU_ARCH_ALL)
1186 STEXI
1187 @item -usb
1188 @findex -usb
1189 Enable the USB driver (if it is not used by default yet).
1190 ETEXI
1192 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
1193 "-usbdevice name add the host or guest USB device 'name'\n",
1194 QEMU_ARCH_ALL)
1195 STEXI
1197 @item -usbdevice @var{devname}
1198 @findex -usbdevice
1199 Add the USB device @var{devname}. Note that this option is deprecated,
1200 please use @code{-device usb-...} instead. @xref{usb_devices}.
1202 @table @option
1204 @item mouse
1205 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1207 @item tablet
1208 Pointer device that uses absolute coordinates (like a touchscreen). This
1209 means QEMU is able to report the mouse position without having to grab the
1210 mouse. Also overrides the PS/2 mouse emulation when activated.
1212 @item braille
1213 Braille device. This will use BrlAPI to display the braille output on a real
1214 or fake device.
1216 @end table
1217 ETEXI
1219 STEXI
1220 @end table
1221 ETEXI
1222 DEFHEADING()
1224 DEFHEADING(Display options:)
1225 STEXI
1226 @table @option
1227 ETEXI
1229 DEF("display", HAS_ARG, QEMU_OPTION_display,
1230 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1231 " [,window_close=on|off][,gl=on|core|es|off]\n"
1232 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1233 "-display vnc=<display>[,<optargs>]\n"
1234 "-display curses\n"
1235 "-display none"
1236 " select display type\n"
1237 "The default display is equivalent to\n"
1238 #if defined(CONFIG_GTK)
1239 "\t\"-display gtk\"\n"
1240 #elif defined(CONFIG_SDL)
1241 "\t\"-display sdl\"\n"
1242 #elif defined(CONFIG_COCOA)
1243 "\t\"-display cocoa\"\n"
1244 #elif defined(CONFIG_VNC)
1245 "\t\"-vnc localhost:0,to=99,id=default\"\n"
1246 #else
1247 "\t\"-display none\"\n"
1248 #endif
1249 , QEMU_ARCH_ALL)
1250 STEXI
1251 @item -display @var{type}
1252 @findex -display
1253 Select type of display to use. This option is a replacement for the
1254 old style -sdl/-curses/... options. Valid values for @var{type} are
1255 @table @option
1256 @item sdl
1257 Display video output via SDL (usually in a separate graphics
1258 window; see the SDL documentation for other possibilities).
1259 @item curses
1260 Display video output via curses. For graphics device models which
1261 support a text mode, QEMU can display this output using a
1262 curses/ncurses interface. Nothing is displayed when the graphics
1263 device is in graphical mode or if the graphics device does not support
1264 a text mode. Generally only the VGA device models support text mode.
1265 @item none
1266 Do not display video output. The guest will still see an emulated
1267 graphics card, but its output will not be displayed to the QEMU
1268 user. This option differs from the -nographic option in that it
1269 only affects what is done with video output; -nographic also changes
1270 the destination of the serial and parallel port data.
1271 @item gtk
1272 Display video output in a GTK window. This interface provides drop-down
1273 menus and other UI elements to configure and control the VM during
1274 runtime.
1275 @item vnc
1276 Start a VNC server on display <arg>
1277 @end table
1278 ETEXI
1280 DEF("nographic", 0, QEMU_OPTION_nographic,
1281 "-nographic disable graphical output and redirect serial I/Os to console\n",
1282 QEMU_ARCH_ALL)
1283 STEXI
1284 @item -nographic
1285 @findex -nographic
1286 Normally, if QEMU is compiled with graphical window support, it displays
1287 output such as guest graphics, guest console, and the QEMU monitor in a
1288 window. With this option, you can totally disable graphical output so
1289 that QEMU is a simple command line application. The emulated serial port
1290 is redirected on the console and muxed with the monitor (unless
1291 redirected elsewhere explicitly). Therefore, you can still use QEMU to
1292 debug a Linux kernel with a serial console. Use @key{C-a h} for help on
1293 switching between the console and monitor.
1294 ETEXI
1296 DEF("curses", 0, QEMU_OPTION_curses,
1297 "-curses shorthand for -display curses\n",
1298 QEMU_ARCH_ALL)
1299 STEXI
1300 @item -curses
1301 @findex -curses
1302 Normally, if QEMU is compiled with graphical window support, it displays
1303 output such as guest graphics, guest console, and the QEMU monitor in a
1304 window. With this option, QEMU can display the VGA output when in text
1305 mode using a curses/ncurses interface. Nothing is displayed in graphical
1306 mode.
1307 ETEXI
1309 DEF("no-frame", 0, QEMU_OPTION_no_frame,
1310 "-no-frame open SDL window without a frame and window decorations\n",
1311 QEMU_ARCH_ALL)
1312 STEXI
1313 @item -no-frame
1314 @findex -no-frame
1315 Do not use decorations for SDL windows and start them using the whole
1316 available screen space. This makes the using QEMU in a dedicated desktop
1317 workspace more convenient.
1318 ETEXI
1320 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1321 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1322 QEMU_ARCH_ALL)
1323 STEXI
1324 @item -alt-grab
1325 @findex -alt-grab
1326 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1327 affects the special keys (for fullscreen, monitor-mode switching, etc).
1328 ETEXI
1330 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1331 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1332 QEMU_ARCH_ALL)
1333 STEXI
1334 @item -ctrl-grab
1335 @findex -ctrl-grab
1336 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1337 affects the special keys (for fullscreen, monitor-mode switching, etc).
1338 ETEXI
1340 DEF("no-quit", 0, QEMU_OPTION_no_quit,
1341 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
1342 STEXI
1343 @item -no-quit
1344 @findex -no-quit
1345 Disable SDL window close capability.
1346 ETEXI
1348 DEF("sdl", 0, QEMU_OPTION_sdl,
1349 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL)
1350 STEXI
1351 @item -sdl
1352 @findex -sdl
1353 Enable SDL.
1354 ETEXI
1356 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1357 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1358 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1359 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1360 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1361 " [,tls-ciphers=<list>]\n"
1362 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1363 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1364 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1365 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1366 " [,jpeg-wan-compression=[auto|never|always]]\n"
1367 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1368 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1369 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1370 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1371 " [,gl=[on|off]][,rendernode=<file>]\n"
1372 " enable spice\n"
1373 " at least one of {port, tls-port} is mandatory\n",
1374 QEMU_ARCH_ALL)
1375 STEXI
1376 @item -spice @var{option}[,@var{option}[,...]]
1377 @findex -spice
1378 Enable the spice remote desktop protocol. Valid options are
1380 @table @option
1382 @item port=<nr>
1383 Set the TCP port spice is listening on for plaintext channels.
1385 @item addr=<addr>
1386 Set the IP address spice is listening on. Default is any address.
1388 @item ipv4
1389 @itemx ipv6
1390 @itemx unix
1391 Force using the specified IP version.
1393 @item password=<secret>
1394 Set the password you need to authenticate.
1396 @item sasl
1397 Require that the client use SASL to authenticate with the spice.
1398 The exact choice of authentication method used is controlled from the
1399 system / user's SASL configuration file for the 'qemu' service. This
1400 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1401 unprivileged user, an environment variable SASL_CONF_PATH can be used
1402 to make it search alternate locations for the service config.
1403 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1404 it is recommended that SASL always be combined with the 'tls' and
1405 'x509' settings to enable use of SSL and server certificates. This
1406 ensures a data encryption preventing compromise of authentication
1407 credentials.
1409 @item disable-ticketing
1410 Allow client connects without authentication.
1412 @item disable-copy-paste
1413 Disable copy paste between the client and the guest.
1415 @item disable-agent-file-xfer
1416 Disable spice-vdagent based file-xfer between the client and the guest.
1418 @item tls-port=<nr>
1419 Set the TCP port spice is listening on for encrypted channels.
1421 @item x509-dir=<dir>
1422 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1424 @item x509-key-file=<file>
1425 @itemx x509-key-password=<file>
1426 @itemx x509-cert-file=<file>
1427 @itemx x509-cacert-file=<file>
1428 @itemx x509-dh-key-file=<file>
1429 The x509 file names can also be configured individually.
1431 @item tls-ciphers=<list>
1432 Specify which ciphers to use.
1434 @item tls-channel=[main|display|cursor|inputs|record|playback]
1435 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1436 Force specific channel to be used with or without TLS encryption. The
1437 options can be specified multiple times to configure multiple
1438 channels. The special name "default" can be used to set the default
1439 mode. For channels which are not explicitly forced into one mode the
1440 spice client is allowed to pick tls/plaintext as he pleases.
1442 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1443 Configure image compression (lossless).
1444 Default is auto_glz.
1446 @item jpeg-wan-compression=[auto|never|always]
1447 @itemx zlib-glz-wan-compression=[auto|never|always]
1448 Configure wan image compression (lossy for slow links).
1449 Default is auto.
1451 @item streaming-video=[off|all|filter]
1452 Configure video stream detection. Default is off.
1454 @item agent-mouse=[on|off]
1455 Enable/disable passing mouse events via vdagent. Default is on.
1457 @item playback-compression=[on|off]
1458 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1460 @item seamless-migration=[on|off]
1461 Enable/disable spice seamless migration. Default is off.
1463 @item gl=[on|off]
1464 Enable/disable OpenGL context. Default is off.
1466 @item rendernode=<file>
1467 DRM render node for OpenGL rendering. If not specified, it will pick
1468 the first available. (Since 2.9)
1470 @end table
1471 ETEXI
1473 DEF("portrait", 0, QEMU_OPTION_portrait,
1474 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1475 QEMU_ARCH_ALL)
1476 STEXI
1477 @item -portrait
1478 @findex -portrait
1479 Rotate graphical output 90 deg left (only PXA LCD).
1480 ETEXI
1482 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1483 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1484 QEMU_ARCH_ALL)
1485 STEXI
1486 @item -rotate @var{deg}
1487 @findex -rotate
1488 Rotate graphical output some deg left (only PXA LCD).
1489 ETEXI
1491 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1492 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1493 " select video card type\n", QEMU_ARCH_ALL)
1494 STEXI
1495 @item -vga @var{type}
1496 @findex -vga
1497 Select type of VGA card to emulate. Valid values for @var{type} are
1498 @table @option
1499 @item cirrus
1500 Cirrus Logic GD5446 Video card. All Windows versions starting from
1501 Windows 95 should recognize and use this graphic card. For optimal
1502 performances, use 16 bit color depth in the guest and the host OS.
1503 (This card was the default before QEMU 2.2)
1504 @item std
1505 Standard VGA card with Bochs VBE extensions. If your guest OS
1506 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1507 to use high resolution modes (>= 1280x1024x16) then you should use
1508 this option. (This card is the default since QEMU 2.2)
1509 @item vmware
1510 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1511 recent XFree86/XOrg server or Windows guest with a driver for this
1512 card.
1513 @item qxl
1514 QXL paravirtual graphic card. It is VGA compatible (including VESA
1515 2.0 VBE support). Works best with qxl guest drivers installed though.
1516 Recommended choice when using the spice protocol.
1517 @item tcx
1518 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1519 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1520 fixed resolution of 1024x768.
1521 @item cg3
1522 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1523 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1524 resolutions aimed at people wishing to run older Solaris versions.
1525 @item virtio
1526 Virtio VGA card.
1527 @item none
1528 Disable VGA card.
1529 @end table
1530 ETEXI
1532 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1533 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1534 STEXI
1535 @item -full-screen
1536 @findex -full-screen
1537 Start in full screen.
1538 ETEXI
1540 DEF("g", 1, QEMU_OPTION_g ,
1541 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1542 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1543 STEXI
1544 @item -g @var{width}x@var{height}[x@var{depth}]
1545 @findex -g
1546 Set the initial graphical resolution and depth (PPC, SPARC only).
1547 ETEXI
1549 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1550 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1551 STEXI
1552 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1553 @findex -vnc
1554 Normally, if QEMU is compiled with graphical window support, it displays
1555 output such as guest graphics, guest console, and the QEMU monitor in a
1556 window. With this option, you can have QEMU listen on VNC display
1557 @var{display} and redirect the VGA display over the VNC session. It is
1558 very useful to enable the usb tablet device when using this option
1559 (option @option{-device usb-tablet}). When using the VNC display, you
1560 must use the @option{-k} parameter to set the keyboard layout if you are
1561 not using en-us. Valid syntax for the @var{display} is
1563 @table @option
1565 @item to=@var{L}
1567 With this option, QEMU will try next available VNC @var{display}s, until the
1568 number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1569 available, e.g. port 5900+@var{display} is already used by another
1570 application. By default, to=0.
1572 @item @var{host}:@var{d}
1574 TCP connections will only be allowed from @var{host} on display @var{d}.
1575 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1576 be omitted in which case the server will accept connections from any host.
1578 @item unix:@var{path}
1580 Connections will be allowed over UNIX domain sockets where @var{path} is the
1581 location of a unix socket to listen for connections on.
1583 @item none
1585 VNC is initialized but not started. The monitor @code{change} command
1586 can be used to later start the VNC server.
1588 @end table
1590 Following the @var{display} value there may be one or more @var{option} flags
1591 separated by commas. Valid options are
1593 @table @option
1595 @item reverse
1597 Connect to a listening VNC client via a ``reverse'' connection. The
1598 client is specified by the @var{display}. For reverse network
1599 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1600 is a TCP port number, not a display number.
1602 @item websocket
1604 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1605 If a bare @var{websocket} option is given, the Websocket port is
1606 5700+@var{display}. An alternative port can be specified with the
1607 syntax @code{websocket}=@var{port}.
1609 If @var{host} is specified connections will only be allowed from this host.
1610 It is possible to control the websocket listen address independently, using
1611 the syntax @code{websocket}=@var{host}:@var{port}.
1613 If no TLS credentials are provided, the websocket connection runs in
1614 unencrypted mode. If TLS credentials are provided, the websocket connection
1615 requires encrypted client connections.
1617 @item password
1619 Require that password based authentication is used for client connections.
1621 The password must be set separately using the @code{set_password} command in
1622 the @ref{pcsys_monitor}. The syntax to change your password is:
1623 @code{set_password <protocol> <password>} where <protocol> could be either
1624 "vnc" or "spice".
1626 If you would like to change <protocol> password expiration, you should use
1627 @code{expire_password <protocol> <expiration-time>} where expiration time could
1628 be one of the following options: now, never, +seconds or UNIX time of
1629 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1630 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1631 date and time).
1633 You can also use keywords "now" or "never" for the expiration time to
1634 allow <protocol> password to expire immediately or never expire.
1636 @item tls-creds=@var{ID}
1638 Provides the ID of a set of TLS credentials to use to secure the
1639 VNC server. They will apply to both the normal VNC server socket
1640 and the websocket socket (if enabled). Setting TLS credentials
1641 will cause the VNC server socket to enable the VeNCrypt auth
1642 mechanism. The credentials should have been previously created
1643 using the @option{-object tls-creds} argument.
1645 The @option{tls-creds} parameter obsoletes the @option{tls},
1646 @option{x509}, and @option{x509verify} options, and as such
1647 it is not permitted to set both new and old type options at
1648 the same time.
1650 @item tls
1652 Require that client use TLS when communicating with the VNC server. This
1653 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1654 attack. It is recommended that this option be combined with either the
1655 @option{x509} or @option{x509verify} options.
1657 This option is now deprecated in favor of using the @option{tls-creds}
1658 argument.
1660 @item x509=@var{/path/to/certificate/dir}
1662 Valid if @option{tls} is specified. Require that x509 credentials are used
1663 for negotiating the TLS session. The server will send its x509 certificate
1664 to the client. It is recommended that a password be set on the VNC server
1665 to provide authentication of the client when this is used. The path following
1666 this option specifies where the x509 certificates are to be loaded from.
1667 See the @ref{vnc_security} section for details on generating certificates.
1669 This option is now deprecated in favour of using the @option{tls-creds}
1670 argument.
1672 @item x509verify=@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, and request that the client send its own x509 certificate.
1677 The server will validate the client's certificate against the CA certificate,
1678 and reject clients when validation fails. If the certificate authority is
1679 trusted, this is a sufficient authentication mechanism. You may still wish
1680 to set a password on the VNC server as a second authentication layer. The
1681 path following this option specifies where the x509 certificates are to
1682 be loaded from. See the @ref{vnc_security} section for details on generating
1683 certificates.
1685 This option is now deprecated in favour of using the @option{tls-creds}
1686 argument.
1688 @item sasl
1690 Require that the client use SASL to authenticate with the VNC server.
1691 The exact choice of authentication method used is controlled from the
1692 system / user's SASL configuration file for the 'qemu' service. This
1693 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1694 unprivileged user, an environment variable SASL_CONF_PATH can be used
1695 to make it search alternate locations for the service config.
1696 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1697 it is recommended that SASL always be combined with the 'tls' and
1698 'x509' settings to enable use of SSL and server certificates. This
1699 ensures a data encryption preventing compromise of authentication
1700 credentials. See the @ref{vnc_security} section for details on using
1701 SASL authentication.
1703 @item acl
1705 Turn on access control lists for checking of the x509 client certificate
1706 and SASL party. For x509 certs, the ACL check is made against the
1707 certificate's distinguished name. This is something that looks like
1708 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1709 made against the username, which depending on the SASL plugin, may
1710 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1711 When the @option{acl} flag is set, the initial access list will be
1712 empty, with a @code{deny} policy. Thus no one will be allowed to
1713 use the VNC server until the ACLs have been loaded. This can be
1714 achieved using the @code{acl} monitor command.
1716 @item lossy
1718 Enable lossy compression methods (gradient, JPEG, ...). If this
1719 option is set, VNC client may receive lossy framebuffer updates
1720 depending on its encoding settings. Enabling this option can save
1721 a lot of bandwidth at the expense of quality.
1723 @item non-adaptive
1725 Disable adaptive encodings. Adaptive encodings are enabled by default.
1726 An adaptive encoding will try to detect frequently updated screen regions,
1727 and send updates in these regions using a lossy encoding (like JPEG).
1728 This can be really helpful to save bandwidth when playing videos. Disabling
1729 adaptive encodings restores the original static behavior of encodings
1730 like Tight.
1732 @item share=[allow-exclusive|force-shared|ignore]
1734 Set display sharing policy. 'allow-exclusive' allows clients to ask
1735 for exclusive access. As suggested by the rfb spec this is
1736 implemented by dropping other connections. Connecting multiple
1737 clients in parallel requires all clients asking for a shared session
1738 (vncviewer: -shared switch). This is the default. 'force-shared'
1739 disables exclusive client access. Useful for shared desktop sessions,
1740 where you don't want someone forgetting specify -shared disconnect
1741 everybody else. 'ignore' completely ignores the shared flag and
1742 allows everybody connect unconditionally. Doesn't conform to the rfb
1743 spec but is traditional QEMU behavior.
1745 @item key-delay-ms
1747 Set keyboard delay, for key down and key up events, in milliseconds.
1748 Default is 10. Keyboards are low-bandwidth devices, so this slowdown
1749 can help the device and guest to keep up and not lose events in case
1750 events are arriving in bulk. Possible causes for the latter are flaky
1751 network connections, or scripts for automated testing.
1753 @end table
1754 ETEXI
1756 STEXI
1757 @end table
1758 ETEXI
1759 ARCHHEADING(, QEMU_ARCH_I386)
1761 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1762 STEXI
1763 @table @option
1764 ETEXI
1766 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1767 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1768 QEMU_ARCH_I386)
1769 STEXI
1770 @item -win2k-hack
1771 @findex -win2k-hack
1772 Use it when installing Windows 2000 to avoid a disk full bug. After
1773 Windows 2000 is installed, you no longer need this option (this option
1774 slows down the IDE transfers).
1775 ETEXI
1777 HXCOMM Deprecated by -rtc
1778 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1780 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1781 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1782 QEMU_ARCH_I386)
1783 STEXI
1784 @item -no-fd-bootchk
1785 @findex -no-fd-bootchk
1786 Disable boot signature checking for floppy disks in BIOS. May
1787 be needed to boot from old floppy disks.
1788 ETEXI
1790 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1791 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1792 STEXI
1793 @item -no-acpi
1794 @findex -no-acpi
1795 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1796 it if your guest OS complains about ACPI problems (PC target machine
1797 only).
1798 ETEXI
1800 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1801 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1802 STEXI
1803 @item -no-hpet
1804 @findex -no-hpet
1805 Disable HPET support.
1806 ETEXI
1808 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1809 "-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"
1810 " ACPI table description\n", QEMU_ARCH_I386)
1811 STEXI
1812 @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}]...]
1813 @findex -acpitable
1814 Add ACPI table with specified header fields and context from specified files.
1815 For file=, take whole ACPI table from the specified files, including all
1816 ACPI headers (possible overridden by other options).
1817 For data=, only data
1818 portion of the table is used, all header information is specified in the
1819 command line.
1820 If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1821 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1822 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1823 spec.
1824 ETEXI
1826 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1827 "-smbios file=binary\n"
1828 " load SMBIOS entry from binary file\n"
1829 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1830 " [,uefi=on|off]\n"
1831 " specify SMBIOS type 0 fields\n"
1832 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1833 " [,uuid=uuid][,sku=str][,family=str]\n"
1834 " specify SMBIOS type 1 fields\n"
1835 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1836 " [,asset=str][,location=str]\n"
1837 " specify SMBIOS type 2 fields\n"
1838 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1839 " [,sku=str]\n"
1840 " specify SMBIOS type 3 fields\n"
1841 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1842 " [,asset=str][,part=str]\n"
1843 " specify SMBIOS type 4 fields\n"
1844 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1845 " [,asset=str][,part=str][,speed=%d]\n"
1846 " specify SMBIOS type 17 fields\n",
1847 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1848 STEXI
1849 @item -smbios file=@var{binary}
1850 @findex -smbios
1851 Load SMBIOS entry from binary file.
1853 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1854 Specify SMBIOS type 0 fields
1856 @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}]
1857 Specify SMBIOS type 1 fields
1859 @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}]
1860 Specify SMBIOS type 2 fields
1862 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1863 Specify SMBIOS type 3 fields
1865 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1866 Specify SMBIOS type 4 fields
1868 @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}]
1869 Specify SMBIOS type 17 fields
1870 ETEXI
1872 STEXI
1873 @end table
1874 ETEXI
1875 DEFHEADING()
1877 DEFHEADING(Network options:)
1878 STEXI
1879 @table @option
1880 ETEXI
1882 HXCOMM Legacy slirp options (now moved to -net user):
1883 #ifdef CONFIG_SLIRP
1884 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1885 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1886 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1887 #ifndef _WIN32
1888 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1889 #endif
1890 #endif
1892 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1893 #ifdef CONFIG_SLIRP
1894 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1895 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1896 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1897 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n"
1898 " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1899 #ifndef _WIN32
1900 "[,smb=dir[,smbserver=addr]]\n"
1901 #endif
1902 " configure a user mode network backend with ID 'str',\n"
1903 " its DHCP server and optional services\n"
1904 #endif
1905 #ifdef _WIN32
1906 "-netdev tap,id=str,ifname=name\n"
1907 " configure a host TAP network backend with ID 'str'\n"
1908 #else
1909 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1910 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1911 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1912 " [,poll-us=n]\n"
1913 " configure a host TAP network backend with ID 'str'\n"
1914 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1915 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1916 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1917 " to deconfigure it\n"
1918 " use '[down]script=no' to disable script execution\n"
1919 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1920 " configure it\n"
1921 " use 'fd=h' to connect to an already opened TAP interface\n"
1922 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1923 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1924 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1925 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1926 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1927 " use vhost=on to enable experimental in kernel accelerator\n"
1928 " (only has effect for virtio guests which use MSIX)\n"
1929 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1930 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1931 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1932 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1933 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n"
1934 " spent on busy polling for vhost net\n"
1935 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1936 " configure a host TAP network backend with ID 'str' that is\n"
1937 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1938 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1939 #endif
1940 #ifdef __linux__
1941 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1942 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1943 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1944 " [,rxcookie=rxcookie][,offset=offset]\n"
1945 " configure a network backend with ID 'str' connected to\n"
1946 " an Ethernet over L2TPv3 pseudowire.\n"
1947 " Linux kernel 3.3+ as well as most routers can talk\n"
1948 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1949 " VM to a router and even VM to Host. It is a nearly-universal\n"
1950 " standard (RFC3391). Note - this implementation uses static\n"
1951 " pre-configured tunnels (same as the Linux kernel).\n"
1952 " use 'src=' to specify source address\n"
1953 " use 'dst=' to specify destination address\n"
1954 " use 'udp=on' to specify udp encapsulation\n"
1955 " use 'srcport=' to specify source udp port\n"
1956 " use 'dstport=' to specify destination udp port\n"
1957 " use 'ipv6=on' to force v6\n"
1958 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1959 " well as a weak security measure\n"
1960 " use 'rxcookie=0x012345678' to specify a rxcookie\n"
1961 " use 'txcookie=0x012345678' to specify a txcookie\n"
1962 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1963 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1964 " use 'pincounter=on' to work around broken counter handling in peer\n"
1965 " use 'offset=X' to add an extra offset between header and data\n"
1966 #endif
1967 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1968 " configure a network backend to connect to another network\n"
1969 " using a socket connection\n"
1970 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1971 " configure a network backend to connect to a multicast maddr and port\n"
1972 " use 'localaddr=addr' to specify the host address to send packets from\n"
1973 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1974 " configure a network backend to connect to another network\n"
1975 " using an UDP tunnel\n"
1976 #ifdef CONFIG_VDE
1977 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1978 " configure a network backend to connect to port 'n' of a vde switch\n"
1979 " running on host and listening for incoming connections on 'socketpath'.\n"
1980 " Use group 'groupname' and mode 'octalmode' to change default\n"
1981 " ownership and permissions for communication port.\n"
1982 #endif
1983 #ifdef CONFIG_NETMAP
1984 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1985 " attach to the existing netmap-enabled network interface 'name', or to a\n"
1986 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1987 " netmap device, defaults to '/dev/netmap')\n"
1988 #endif
1989 #ifdef CONFIG_POSIX
1990 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
1991 " configure a vhost-user network, backed by a chardev 'dev'\n"
1992 #endif
1993 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
1994 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL)
1995 DEF("nic", HAS_ARG, QEMU_OPTION_nic,
1996 "--nic [tap|bridge|"
1997 #ifdef CONFIG_SLIRP
1998 "user|"
1999 #endif
2000 #ifdef __linux__
2001 "l2tpv3|"
2002 #endif
2003 #ifdef CONFIG_VDE
2004 "vde|"
2005 #endif
2006 #ifdef CONFIG_NETMAP
2007 "netmap|"
2008 #endif
2009 #ifdef CONFIG_POSIX
2010 "vhost-user|"
2011 #endif
2012 "socket][,option][,...][mac=macaddr]\n"
2013 " initialize an on-board / default host NIC (using MAC address\n"
2014 " macaddr) and connect it to the given host network backend\n"
2015 "--nic none use it alone to have zero network devices (the default is to\n"
2016 " provided a 'user' network connection)\n",
2017 QEMU_ARCH_ALL)
2018 DEF("net", HAS_ARG, QEMU_OPTION_net,
2019 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2020 " configure or create an on-board (or machine default) NIC and\n"
2021 " connect it to hub 0 (please use -nic unless you need a hub)\n"
2022 "-net ["
2023 #ifdef CONFIG_SLIRP
2024 "user|"
2025 #endif
2026 "tap|"
2027 "bridge|"
2028 #ifdef CONFIG_VDE
2029 "vde|"
2030 #endif
2031 #ifdef CONFIG_NETMAP
2032 "netmap|"
2033 #endif
2034 "socket][,option][,option][,...]\n"
2035 " old way to initialize a host network interface\n"
2036 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2037 STEXI
2038 @item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn]
2039 @findex -nic
2040 This option is a shortcut for configuring both the on-board (default) guest
2041 NIC hardware and the host network backend in one go. The host backend options
2042 are the same as with the corresponding @option{-netdev} options below.
2043 The guest NIC model can be set with @option{model=@var{modelname}}.
2044 Use @option{model=help} to list the available device types.
2045 The hardware MAC address can be set with @option{mac=@var{macaddr}}.
2047 The following two example do exactly the same, to show how @option{-nic} can
2048 be used to shorten the command line length (note that the e1000 is the default
2049 on i386, so the @option{model=e1000} parameter could even be omitted here, too):
2050 @example
2051 qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32
2052 qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32
2053 @end example
2055 @item -nic none
2056 Indicate that no network devices should be configured. It is used to override
2057 the default configuration (default NIC with ``user'' host network backend)
2058 which is activated if no other networking options are provided.
2060 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2061 @findex -netdev
2062 Configure user mode host network backend which requires no administrator
2063 privilege to run. Valid options are:
2065 @table @option
2066 @item id=@var{id}
2067 Assign symbolic name for use in monitor commands.
2069 @item ipv4=on|off and ipv6=on|off
2070 Specify that either IPv4 or IPv6 must be enabled. If neither is specified
2071 both protocols are enabled.
2073 @item net=@var{addr}[/@var{mask}]
2074 Set IP network address the guest will see. Optionally specify the netmask,
2075 either in the form a.b.c.d or as number of valid top-most bits. Default is
2076 10.0.2.0/24.
2078 @item host=@var{addr}
2079 Specify the guest-visible address of the host. Default is the 2nd IP in the
2080 guest network, i.e. x.x.x.2.
2082 @item ipv6-net=@var{addr}[/@var{int}]
2083 Set IPv6 network address the guest will see (default is fec0::/64). The
2084 network prefix is given in the usual hexadecimal IPv6 address
2085 notation. The prefix size is optional, and is given as the number of
2086 valid top-most bits (default is 64).
2088 @item ipv6-host=@var{addr}
2089 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2090 the guest network, i.e. xxxx::2.
2092 @item restrict=on|off
2093 If this option is enabled, the guest will be isolated, i.e. it will not be
2094 able to contact the host and no guest IP packets will be routed over the host
2095 to the outside. This option does not affect any explicitly set forwarding rules.
2097 @item hostname=@var{name}
2098 Specifies the client hostname reported by the built-in DHCP server.
2100 @item dhcpstart=@var{addr}
2101 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2102 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2104 @item dns=@var{addr}
2105 Specify the guest-visible address of the virtual nameserver. The address must
2106 be different from the host address. Default is the 3rd IP in the guest network,
2107 i.e. x.x.x.3.
2109 @item ipv6-dns=@var{addr}
2110 Specify the guest-visible address of the IPv6 virtual nameserver. The address
2111 must be different from the host address. Default is the 3rd IP in the guest
2112 network, i.e. xxxx::3.
2114 @item dnssearch=@var{domain}
2115 Provides an entry for the domain-search list sent by the built-in
2116 DHCP server. More than one domain suffix can be transmitted by specifying
2117 this option multiple times. If supported, this will cause the guest to
2118 automatically try to append the given domain suffix(es) in case a domain name
2119 can not be resolved.
2121 Example:
2122 @example
2123 qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org
2124 @end example
2126 @item domainname=@var{domain}
2127 Specifies the client domain name reported by the built-in DHCP server.
2129 @item tftp=@var{dir}
2130 When using the user mode network stack, activate a built-in TFTP
2131 server. The files in @var{dir} will be exposed as the root of a TFTP server.
2132 The TFTP client on the guest must be configured in binary mode (use the command
2133 @code{bin} of the Unix TFTP client).
2135 @item bootfile=@var{file}
2136 When using the user mode network stack, broadcast @var{file} as the BOOTP
2137 filename. In conjunction with @option{tftp}, this can be used to network boot
2138 a guest from a local directory.
2140 Example (using pxelinux):
2141 @example
2142 qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \
2143 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2144 @end example
2146 @item smb=@var{dir}[,smbserver=@var{addr}]
2147 When using the user mode network stack, activate a built-in SMB
2148 server so that Windows OSes can access to the host files in @file{@var{dir}}
2149 transparently. The IP address of the SMB server can be set to @var{addr}. By
2150 default the 4th IP in the guest network is used, i.e. x.x.x.4.
2152 In the guest Windows OS, the line:
2153 @example
2154 10.0.2.4 smbserver
2155 @end example
2156 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2157 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2159 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2161 Note that a SAMBA server must be installed on the host OS.
2163 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2164 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2165 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2166 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2167 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2168 be bound to a specific host interface. If no connection type is set, TCP is
2169 used. This option can be given multiple times.
2171 For example, to redirect host X11 connection from screen 1 to guest
2172 screen 0, use the following:
2174 @example
2175 # on the host
2176 qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000
2177 # this host xterm should open in the guest X11 server
2178 xterm -display :1
2179 @end example
2181 To redirect telnet connections from host port 5555 to telnet port on
2182 the guest, use the following:
2184 @example
2185 # on the host
2186 qemu-system-i386 -nic user,hostfwd=tcp::5555-:23
2187 telnet localhost 5555
2188 @end example
2190 Then when you use on the host @code{telnet localhost 5555}, you
2191 connect to the guest telnet server.
2193 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2194 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2195 Forward guest TCP connections to the IP address @var{server} on port @var{port}
2196 to the character device @var{dev} or to a program executed by @var{cmd:command}
2197 which gets spawned for each connection. This option can be given multiple times.
2199 You can either use a chardev directly and have that one used throughout QEMU's
2200 lifetime, like in the following example:
2202 @example
2203 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
2204 # the guest accesses it
2205 qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321
2206 @end example
2208 Or you can execute a command on every TCP connection established by the guest,
2209 so that QEMU behaves similar to an inetd process for that virtual server:
2211 @example
2212 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
2213 # and connect the TCP stream to its stdin/stdout
2214 qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2215 @end example
2217 @end table
2219 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
2220 processed and applied to -net user. Mixing them with the new configuration
2221 syntax gives undefined results. Their use for new applications is discouraged
2222 as they will be removed from future versions.
2224 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2225 Configure a host TAP network backend with ID @var{id}.
2227 Use the network script @var{file} to configure it and the network script
2228 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
2229 automatically provides one. The default network configure script is
2230 @file{/etc/qemu-ifup} and the default network deconfigure script is
2231 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
2232 to disable script execution.
2234 If running QEMU as an unprivileged user, use the network helper
2235 @var{helper} to configure the TAP interface and attach it to the bridge.
2236 The default network helper executable is @file{/path/to/qemu-bridge-helper}
2237 and the default bridge device is @file{br0}.
2239 @option{fd}=@var{h} can be used to specify the handle of an already
2240 opened host TAP interface.
2242 Examples:
2244 @example
2245 #launch a QEMU instance with the default network script
2246 qemu-system-i386 linux.img -nic tap
2247 @end example
2249 @example
2250 #launch a QEMU instance with two NICs, each one connected
2251 #to a TAP device
2252 qemu-system-i386 linux.img \
2253 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \
2254 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1
2255 @end example
2257 @example
2258 #launch a QEMU instance with the default network helper to
2259 #connect a TAP device to bridge br0
2260 qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \
2261 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper"
2262 @end example
2264 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
2265 Connect a host TAP network interface to a host bridge device.
2267 Use the network helper @var{helper} to configure the TAP interface and
2268 attach it to the bridge. The default network helper executable is
2269 @file{/path/to/qemu-bridge-helper} and the default bridge
2270 device is @file{br0}.
2272 Examples:
2274 @example
2275 #launch a QEMU instance with the default network helper to
2276 #connect a TAP device to bridge br0
2277 qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1
2278 @end example
2280 @example
2281 #launch a QEMU instance with the default network helper to
2282 #connect a TAP device to bridge qemubr0
2283 qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1
2284 @end example
2286 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2288 This host network backend can be used to connect the guest's network to
2289 another QEMU virtual machine using a TCP socket connection. If @option{listen}
2290 is specified, QEMU waits for incoming connections on @var{port}
2291 (@var{host} is optional). @option{connect} is used to connect to
2292 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
2293 specifies an already opened TCP socket.
2295 Example:
2296 @example
2297 # launch a first QEMU instance
2298 qemu-system-i386 linux.img \
2299 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2300 -netdev socket,id=n1,listen=:1234
2301 # connect the network of this instance to the network of the first instance
2302 qemu-system-i386 linux.img \
2303 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \
2304 -netdev socket,id=n2,connect=127.0.0.1:1234
2305 @end example
2307 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2309 Configure a socket host network backend to share the guest's network traffic
2310 with another QEMU virtual machines using a UDP multicast socket, effectively
2311 making a bus for every QEMU with same multicast address @var{maddr} and @var{port}.
2312 NOTES:
2313 @enumerate
2314 @item
2315 Several QEMU can be running on different hosts and share same bus (assuming
2316 correct multicast setup for these hosts).
2317 @item
2318 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
2319 @url{http://user-mode-linux.sf.net}.
2320 @item
2321 Use @option{fd=h} to specify an already opened UDP multicast socket.
2322 @end enumerate
2324 Example:
2325 @example
2326 # launch one QEMU instance
2327 qemu-system-i386 linux.img \
2328 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2329 -netdev socket,id=n1,mcast=230.0.0.1:1234
2330 # launch another QEMU instance on same "bus"
2331 qemu-system-i386 linux.img \
2332 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \
2333 -netdev socket,id=n2,mcast=230.0.0.1:1234
2334 # launch yet another QEMU instance on same "bus"
2335 qemu-system-i386 linux.img \
2336 -device e1000,netdev=n3,macaddr=52:54:00:12:34:58 \
2337 -netdev socket,id=n3,mcast=230.0.0.1:1234
2338 @end example
2340 Example (User Mode Linux compat.):
2341 @example
2342 # launch QEMU instance (note mcast address selected is UML's default)
2343 qemu-system-i386 linux.img \
2344 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2345 -netdev socket,id=n1,mcast=239.192.168.1:1102
2346 # launch UML
2347 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2348 @end example
2350 Example (send packets from host's 1.2.3.4):
2351 @example
2352 qemu-system-i386 linux.img \
2353 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2354 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2355 @end example
2357 @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}]
2358 Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a
2359 popular protocol to transport Ethernet (and other Layer 2) data frames between
2360 two systems. It is present in routers, firewalls and the Linux kernel
2361 (from version 3.3 onwards).
2363 This transport allows a VM to communicate to another VM, router or firewall directly.
2365 @table @option
2366 @item src=@var{srcaddr}
2367 source address (mandatory)
2368 @item dst=@var{dstaddr}
2369 destination address (mandatory)
2370 @item udp
2371 select udp encapsulation (default is ip).
2372 @item srcport=@var{srcport}
2373 source udp port.
2374 @item dstport=@var{dstport}
2375 destination udp port.
2376 @item ipv6
2377 force v6, otherwise defaults to v4.
2378 @item rxcookie=@var{rxcookie}
2379 @itemx txcookie=@var{txcookie}
2380 Cookies are a weak form of security in the l2tpv3 specification.
2381 Their function is mostly to prevent misconfiguration. By default they are 32
2382 bit.
2383 @item cookie64
2384 Set cookie size to 64 bit instead of the default 32
2385 @item counter=off
2386 Force a 'cut-down' L2TPv3 with no counter as in
2387 draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2388 @item pincounter=on
2389 Work around broken counter handling in peer. This may also help on
2390 networks which have packet reorder.
2391 @item offset=@var{offset}
2392 Add an extra offset between header and data
2393 @end table
2395 For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2396 on the remote Linux host 1.2.3.4:
2397 @example
2398 # Setup tunnel on linux host using raw ip as encapsulation
2399 # on 1.2.3.4
2400 ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2401 encap udp udp_sport 16384 udp_dport 16384
2402 ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2403 0xFFFFFFFF peer_session_id 0xFFFFFFFF
2404 ifconfig vmtunnel0 mtu 1500
2405 ifconfig vmtunnel0 up
2406 brctl addif br-lan vmtunnel0
2409 # on 4.3.2.1
2410 # launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2412 qemu-system-i386 linux.img -device e1000,netdev=n1 \
2413 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter
2415 @end example
2417 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2418 Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and
2419 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2420 and MODE @var{octalmode} to change default ownership and permissions for
2421 communication port. This option is only available if QEMU has been compiled
2422 with vde support enabled.
2424 Example:
2425 @example
2426 # launch vde switch
2427 vde_switch -F -sock /tmp/myswitch
2428 # launch QEMU instance
2429 qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch
2430 @end example
2432 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2434 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2435 be a unix domain socket backed one. The vhost-user uses a specifically defined
2436 protocol to pass vhost ioctl replacement messages to an application on the other
2437 end of the socket. On non-MSIX guests, the feature can be forced with
2438 @var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2439 be created for multiqueue vhost-user.
2441 Example:
2442 @example
2443 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2444 -numa node,memdev=mem \
2445 -chardev socket,id=chr0,path=/path/to/socket \
2446 -netdev type=vhost-user,id=net0,chardev=chr0 \
2447 -device virtio-net-pci,netdev=net0
2448 @end example
2450 @item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}]
2452 Create a hub port on the emulated hub with ID @var{hubid}.
2454 The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a
2455 single netdev. Alternatively, you can also connect the hubport to another
2456 netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option.
2458 @item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2459 @findex -net
2460 Legacy option to configure or create an on-board (or machine default) Network
2461 Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e.
2462 the default hub), or to the netdev @var{nd}.
2463 The NIC is an e1000 by default on the PC target. Optionally, the MAC address
2464 can be changed to @var{mac}, the device address set to @var{addr} (PCI cards
2465 only), and a @var{name} can be assigned for use in monitor commands.
2466 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2467 that the card should have; this option currently only affects virtio cards; set
2468 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2469 NIC is created. QEMU can emulate several different models of network card.
2470 Use @code{-net nic,model=help} for a list of available devices for your target.
2472 @item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}]
2473 Configure a host network backend (with the options corresponding to the same
2474 @option{-netdev} option) and connect it to the emulated hub 0 (the default
2475 hub). Use @var{name} to specify the name of the hub port.
2476 ETEXI
2478 STEXI
2479 @end table
2480 ETEXI
2481 DEFHEADING()
2483 DEFHEADING(Character device options:)
2485 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2486 "-chardev help\n"
2487 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2488 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2489 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2490 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2491 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2492 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2493 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2494 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2495 " [,logfile=PATH][,logappend=on|off]\n"
2496 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2497 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2498 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2499 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2500 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2501 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2502 #ifdef _WIN32
2503 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2504 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2505 #else
2506 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2507 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2508 #endif
2509 #ifdef CONFIG_BRLAPI
2510 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2511 #endif
2512 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2513 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2514 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2515 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2516 #endif
2517 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2518 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2519 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2520 #endif
2521 #if defined(CONFIG_SPICE)
2522 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2523 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2524 #endif
2525 , QEMU_ARCH_ALL
2528 STEXI
2530 The general form of a character device option is:
2531 @table @option
2532 @item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}]
2533 @findex -chardev
2534 Backend is one of:
2535 @option{null},
2536 @option{socket},
2537 @option{udp},
2538 @option{msmouse},
2539 @option{vc},
2540 @option{ringbuf},
2541 @option{file},
2542 @option{pipe},
2543 @option{console},
2544 @option{serial},
2545 @option{pty},
2546 @option{stdio},
2547 @option{braille},
2548 @option{tty},
2549 @option{parallel},
2550 @option{parport},
2551 @option{spicevmc},
2552 @option{spiceport}.
2553 The specific backend will determine the applicable options.
2555 Use @code{-chardev help} to print all available chardev backend types.
2557 All devices must have an id, which can be any string up to 127 characters long.
2558 It is used to uniquely identify this device in other command line directives.
2560 A character device may be used in multiplexing mode by multiple front-ends.
2561 Specify @option{mux=on} to enable this mode.
2562 A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2563 backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2564 If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2565 create a multiplexer with your specified ID, and you can then configure multiple
2566 front ends to use that chardev ID for their input/output. Up to four different
2567 front ends can be connected to a single multiplexed chardev. (Without
2568 multiplexing enabled, a chardev can only be used by a single front end.)
2569 For instance you could use this to allow a single stdio chardev to be used by
2570 two serial ports and the QEMU monitor:
2572 @example
2573 -chardev stdio,mux=on,id=char0 \
2574 -mon chardev=char0,mode=readline \
2575 -serial chardev:char0 \
2576 -serial chardev:char0
2577 @end example
2579 You can have more than one multiplexer in a system configuration; for instance
2580 you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2581 multiplexed between the QEMU monitor and a parallel port:
2583 @example
2584 -chardev stdio,mux=on,id=char0 \
2585 -mon chardev=char0,mode=readline \
2586 -parallel chardev:char0 \
2587 -chardev tcp,...,mux=on,id=char1 \
2588 -serial chardev:char1 \
2589 -serial chardev:char1
2590 @end example
2592 When you're using a multiplexed character device, some escape sequences are
2593 interpreted in the input. @xref{mux_keys, Keys in the character backend
2594 multiplexer}.
2596 Note that some other command line options may implicitly create multiplexed
2597 character backends; for instance @option{-serial mon:stdio} creates a
2598 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2599 and @option{-nographic} also multiplexes the console and the monitor to
2600 stdio.
2602 There is currently no support for multiplexing in the other direction
2603 (where a single QEMU front end takes input and output from multiple chardevs).
2605 Every backend supports the @option{logfile} option, which supplies the path
2606 to a file to record all data transmitted via the backend. The @option{logappend}
2607 option controls whether the log file will be truncated or appended to when
2608 opened.
2610 @end table
2612 The available backends are:
2614 @table @option
2615 @item -chardev null,id=@var{id}
2616 A void device. This device will not emit any data, and will drop any data it
2617 receives. The null backend does not take any options.
2619 @item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,reconnect=@var{seconds}][,tls-creds=@var{id}]
2621 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2622 unix socket will be created if @option{path} is specified. Behaviour is
2623 undefined if TCP options are specified for a unix socket.
2625 @option{server} specifies that the socket shall be a listening socket.
2627 @option{nowait} specifies that QEMU should not block waiting for a client to
2628 connect to a listening socket.
2630 @option{telnet} specifies that traffic on the socket should interpret telnet
2631 escape sequences.
2633 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2634 the remote end goes away. qemu will delay this many seconds and then attempt
2635 to reconnect. Zero disables reconnecting, and is the default.
2637 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2638 and specifies the id of the TLS credentials to use for the handshake. The
2639 credentials must be previously created with the @option{-object tls-creds}
2640 argument.
2642 TCP and unix socket options are given below:
2644 @table @option
2646 @item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay]
2648 @option{host} for a listening socket specifies the local address to be bound.
2649 For a connecting socket species the remote host to connect to. @option{host} is
2650 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2652 @option{port} for a listening socket specifies the local port to be bound. For a
2653 connecting socket specifies the port on the remote host to connect to.
2654 @option{port} can be given as either a port number or a service name.
2655 @option{port} is required.
2657 @option{to} is only relevant to listening sockets. If it is specified, and
2658 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2659 to and including @option{to} until it succeeds. @option{to} must be specified
2660 as a port number.
2662 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2663 If neither is specified the socket may use either protocol.
2665 @option{nodelay} disables the Nagle algorithm.
2667 @item unix options: path=@var{path}
2669 @option{path} specifies the local path of the unix socket. @option{path} is
2670 required.
2672 @end table
2674 @item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6]
2676 Sends all traffic from the guest to a remote host over UDP.
2678 @option{host} specifies the remote host to connect to. If not specified it
2679 defaults to @code{localhost}.
2681 @option{port} specifies the port on the remote host to connect to. @option{port}
2682 is required.
2684 @option{localaddr} specifies the local address to bind to. If not specified it
2685 defaults to @code{0.0.0.0}.
2687 @option{localport} specifies the local port to bind to. If not specified any
2688 available local port will be used.
2690 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2691 If neither is specified the device may use either protocol.
2693 @item -chardev msmouse,id=@var{id}
2695 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2696 take any options.
2698 @item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]]
2700 Connect to a QEMU text console. @option{vc} may optionally be given a specific
2701 size.
2703 @option{width} and @option{height} specify the width and height respectively of
2704 the console, in pixels.
2706 @option{cols} and @option{rows} specify that the console be sized to fit a text
2707 console with the given dimensions.
2709 @item -chardev ringbuf,id=@var{id}[,size=@var{size}]
2711 Create a ring buffer with fixed size @option{size}.
2712 @var{size} must be a power of two and defaults to @code{64K}.
2714 @item -chardev file,id=@var{id},path=@var{path}
2716 Log all traffic received from the guest to a file.
2718 @option{path} specifies the path of the file to be opened. This file will be
2719 created if it does not already exist, and overwritten if it does. @option{path}
2720 is required.
2722 @item -chardev pipe,id=@var{id},path=@var{path}
2724 Create a two-way connection to the guest. The behaviour differs slightly between
2725 Windows hosts and other hosts:
2727 On Windows, a single duplex pipe will be created at
2728 @file{\\.pipe\@option{path}}.
2730 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2731 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2732 received by the guest. Data written by the guest can be read from
2733 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2734 be present.
2736 @option{path} forms part of the pipe path as described above. @option{path} is
2737 required.
2739 @item -chardev console,id=@var{id}
2741 Send traffic from the guest to QEMU's standard output. @option{console} does not
2742 take any options.
2744 @option{console} is only available on Windows hosts.
2746 @item -chardev serial,id=@var{id},path=@option{path}
2748 Send traffic from the guest to a serial device on the host.
2750 On Unix hosts serial will actually accept any tty device,
2751 not only serial lines.
2753 @option{path} specifies the name of the serial device to open.
2755 @item -chardev pty,id=@var{id}
2757 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2758 not take any options.
2760 @option{pty} is not available on Windows hosts.
2762 @item -chardev stdio,id=@var{id}[,signal=on|off]
2763 Connect to standard input and standard output of the QEMU process.
2765 @option{signal} controls if signals are enabled on the terminal, that includes
2766 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2767 default, use @option{signal=off} to disable it.
2769 @item -chardev braille,id=@var{id}
2771 Connect to a local BrlAPI server. @option{braille} does not take any options.
2773 @item -chardev tty,id=@var{id},path=@var{path}
2775 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2776 DragonFlyBSD hosts. It is an alias for @option{serial}.
2778 @option{path} specifies the path to the tty. @option{path} is required.
2780 @item -chardev parallel,id=@var{id},path=@var{path}
2781 @itemx -chardev parport,id=@var{id},path=@var{path}
2783 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2785 Connect to a local parallel port.
2787 @option{path} specifies the path to the parallel port device. @option{path} is
2788 required.
2790 @item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name}
2792 @option{spicevmc} is only available when spice support is built in.
2794 @option{debug} debug level for spicevmc
2796 @option{name} name of spice channel to connect to
2798 Connect to a spice virtual machine channel, such as vdiport.
2800 @item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name}
2802 @option{spiceport} is only available when spice support is built in.
2804 @option{debug} debug level for spicevmc
2806 @option{name} name of spice port to connect to
2808 Connect to a spice port, allowing a Spice client to handle the traffic
2809 identified by a name (preferably a fqdn).
2810 ETEXI
2812 STEXI
2813 @end table
2814 ETEXI
2815 DEFHEADING()
2817 DEFHEADING(Bluetooth(R) options:)
2818 STEXI
2819 @table @option
2820 ETEXI
2822 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2823 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2824 "-bt hci,host[:id]\n" \
2825 " use host's HCI with the given name\n" \
2826 "-bt hci[,vlan=n]\n" \
2827 " emulate a standard HCI in virtual scatternet 'n'\n" \
2828 "-bt vhci[,vlan=n]\n" \
2829 " add host computer to virtual scatternet 'n' using VHCI\n" \
2830 "-bt device:dev[,vlan=n]\n" \
2831 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2832 QEMU_ARCH_ALL)
2833 STEXI
2834 @item -bt hci[...]
2835 @findex -bt
2836 Defines the function of the corresponding Bluetooth HCI. -bt options
2837 are matched with the HCIs present in the chosen machine type. For
2838 example when emulating a machine with only one HCI built into it, only
2839 the first @code{-bt hci[...]} option is valid and defines the HCI's
2840 logic. The Transport Layer is decided by the machine type. Currently
2841 the machines @code{n800} and @code{n810} have one HCI and all other
2842 machines have none.
2844 @anchor{bt-hcis}
2845 The following three types are recognized:
2847 @table @option
2848 @item -bt hci,null
2849 (default) The corresponding Bluetooth HCI assumes no internal logic
2850 and will not respond to any HCI commands or emit events.
2852 @item -bt hci,host[:@var{id}]
2853 (@code{bluez} only) The corresponding HCI passes commands / events
2854 to / from the physical HCI identified by the name @var{id} (default:
2855 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2856 capable systems like Linux.
2858 @item -bt hci[,vlan=@var{n}]
2859 Add a virtual, standard HCI that will participate in the Bluetooth
2860 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2861 VLANs, devices inside a bluetooth network @var{n} can only communicate
2862 with other devices in the same network (scatternet).
2863 @end table
2865 @item -bt vhci[,vlan=@var{n}]
2866 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2867 to the host bluetooth stack instead of to the emulated target. This
2868 allows the host and target machines to participate in a common scatternet
2869 and communicate. Requires the Linux @code{vhci} driver installed. Can
2870 be used as following:
2872 @example
2873 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2874 @end example
2876 @item -bt device:@var{dev}[,vlan=@var{n}]
2877 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2878 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2879 currently:
2881 @table @option
2882 @item keyboard
2883 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2884 @end table
2885 ETEXI
2887 STEXI
2888 @end table
2889 ETEXI
2890 DEFHEADING()
2892 #ifdef CONFIG_TPM
2893 DEFHEADING(TPM device options:)
2895 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2896 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2897 " use path to provide path to a character device; default is /dev/tpm0\n"
2898 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2899 " not provided it will be searched for in /sys/class/misc/tpm?/device\n"
2900 "-tpmdev emulator,id=id,chardev=dev\n"
2901 " configure the TPM device using chardev backend\n",
2902 QEMU_ARCH_ALL)
2903 STEXI
2905 The general form of a TPM device option is:
2906 @table @option
2908 @item -tpmdev @var{backend},id=@var{id}[,@var{options}]
2909 @findex -tpmdev
2911 The specific backend type will determine the applicable options.
2912 The @code{-tpmdev} option creates the TPM backend and requires a
2913 @code{-device} option that specifies the TPM frontend interface model.
2915 Use @code{-tpmdev help} to print all available TPM backend types.
2917 @end table
2919 The available backends are:
2921 @table @option
2923 @item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path}
2925 (Linux-host only) Enable access to the host's TPM using the passthrough
2926 driver.
2928 @option{path} specifies the path to the host's TPM device, i.e., on
2929 a Linux host this would be @code{/dev/tpm0}.
2930 @option{path} is optional and by default @code{/dev/tpm0} is used.
2932 @option{cancel-path} specifies the path to the host TPM device's sysfs
2933 entry allowing for cancellation of an ongoing TPM command.
2934 @option{cancel-path} is optional and by default QEMU will search for the
2935 sysfs entry to use.
2937 Some notes about using the host's TPM with the passthrough driver:
2939 The TPM device accessed by the passthrough driver must not be
2940 used by any other application on the host.
2942 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2943 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2944 TPM again and may therefore not show a TPM-specific menu that would
2945 otherwise allow the user to configure the TPM, e.g., allow the user to
2946 enable/disable or activate/deactivate the TPM.
2947 Further, if TPM ownership is released from within a VM then the host's TPM
2948 will get disabled and deactivated. To enable and activate the
2949 TPM again afterwards, the host has to be rebooted and the user is
2950 required to enter the firmware's menu to enable and activate the TPM.
2951 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2953 To create a passthrough TPM use the following two options:
2954 @example
2955 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2956 @end example
2957 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2958 @code{tpmdev=tpm0} in the device option.
2960 @item -tpmdev emulator,id=@var{id},chardev=@var{dev}
2962 (Linux-host only) Enable access to a TPM emulator using Unix domain socket based
2963 chardev backend.
2965 @option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
2967 To create a TPM emulator backend device with chardev socket backend:
2968 @example
2970 -chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
2972 @end example
2974 ETEXI
2976 STEXI
2977 @end table
2978 ETEXI
2979 DEFHEADING()
2981 #endif
2983 DEFHEADING(Linux/Multiboot boot specific:)
2984 STEXI
2986 When using these options, you can use a given Linux or Multiboot
2987 kernel without installing it in the disk image. It can be useful
2988 for easier testing of various kernels.
2990 @table @option
2991 ETEXI
2993 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2994 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2995 STEXI
2996 @item -kernel @var{bzImage}
2997 @findex -kernel
2998 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2999 or in multiboot format.
3000 ETEXI
3002 DEF("append", HAS_ARG, QEMU_OPTION_append, \
3003 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
3004 STEXI
3005 @item -append @var{cmdline}
3006 @findex -append
3007 Use @var{cmdline} as kernel command line
3008 ETEXI
3010 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
3011 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
3012 STEXI
3013 @item -initrd @var{file}
3014 @findex -initrd
3015 Use @var{file} as initial ram disk.
3017 @item -initrd "@var{file1} arg=foo,@var{file2}"
3019 This syntax is only available with multiboot.
3021 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3022 first module.
3023 ETEXI
3025 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
3026 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
3027 STEXI
3028 @item -dtb @var{file}
3029 @findex -dtb
3030 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3031 on boot.
3032 ETEXI
3034 STEXI
3035 @end table
3036 ETEXI
3037 DEFHEADING()
3039 DEFHEADING(Debug/Expert options:)
3040 STEXI
3041 @table @option
3042 ETEXI
3044 DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
3045 "-fw_cfg [name=]<name>,file=<file>\n"
3046 " add named fw_cfg entry with contents from file\n"
3047 "-fw_cfg [name=]<name>,string=<str>\n"
3048 " add named fw_cfg entry with contents from string\n",
3049 QEMU_ARCH_ALL)
3050 STEXI
3052 @item -fw_cfg [name=]@var{name},file=@var{file}
3053 @findex -fw_cfg
3054 Add named fw_cfg entry with contents from file @var{file}.
3056 @item -fw_cfg [name=]@var{name},string=@var{str}
3057 Add named fw_cfg entry with contents from string @var{str}.
3059 The terminating NUL character of the contents of @var{str} will not be
3060 included as part of the fw_cfg item data. To insert contents with
3061 embedded NUL characters, you have to use the @var{file} parameter.
3063 The fw_cfg entries are passed by QEMU through to the guest.
3065 Example:
3066 @example
3067 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3068 @end example
3069 creates an fw_cfg entry named opt/com.mycompany/blob with contents
3070 from ./my_blob.bin.
3072 ETEXI
3074 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
3075 "-serial dev redirect the serial port to char device 'dev'\n",
3076 QEMU_ARCH_ALL)
3077 STEXI
3078 @item -serial @var{dev}
3079 @findex -serial
3080 Redirect the virtual serial port to host character device
3081 @var{dev}. The default device is @code{vc} in graphical mode and
3082 @code{stdio} in non graphical mode.
3084 This option can be used several times to simulate up to 4 serial
3085 ports.
3087 Use @code{-serial none} to disable all serial ports.
3089 Available character devices are:
3090 @table @option
3091 @item vc[:@var{W}x@var{H}]
3092 Virtual console. Optionally, a width and height can be given in pixel with
3093 @example
3094 vc:800x600
3095 @end example
3096 It is also possible to specify width or height in characters:
3097 @example
3098 vc:80Cx24C
3099 @end example
3100 @item pty
3101 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
3102 @item none
3103 No device is allocated.
3104 @item null
3105 void device
3106 @item chardev:@var{id}
3107 Use a named character device defined with the @code{-chardev} option.
3108 @item /dev/XXX
3109 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3110 parameters are set according to the emulated ones.
3111 @item /dev/parport@var{N}
3112 [Linux only, parallel port only] Use host parallel port
3113 @var{N}. Currently SPP and EPP parallel port features can be used.
3114 @item file:@var{filename}
3115 Write output to @var{filename}. No character can be read.
3116 @item stdio
3117 [Unix only] standard input/output
3118 @item pipe:@var{filename}
3119 name pipe @var{filename}
3120 @item COM@var{n}
3121 [Windows only] Use host serial port @var{n}
3122 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3123 This implements UDP Net Console.
3124 When @var{remote_host} or @var{src_ip} are not specified
3125 they default to @code{0.0.0.0}.
3126 When not using a specified @var{src_port} a random port is automatically chosen.
3128 If you just want a simple readonly console you can use @code{netcat} or
3129 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3130 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3131 will appear in the netconsole session.
3133 If you plan to send characters back via netconsole or you want to stop
3134 and start QEMU a lot of times, you should have QEMU use the same
3135 source port each time by using something like @code{-serial
3136 udp::4555@@:4556} to QEMU. Another approach is to use a patched
3137 version of netcat which can listen to a TCP port and send and receive
3138 characters via udp. If you have a patched version of netcat which
3139 activates telnet remote echo and single char transfer, then you can
3140 use the following options to set up a netcat redirector to allow
3141 telnet on port 5555 to access the QEMU port.
3142 @table @code
3143 @item QEMU Options:
3144 -serial udp::4555@@:4556
3145 @item netcat options:
3146 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3147 @item telnet options:
3148 localhost 5555
3149 @end table
3151 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3152 The TCP Net Console has two modes of operation. It can send the serial
3153 I/O to a location or wait for a connection from a location. By default
3154 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
3155 the @var{server} option QEMU will wait for a client socket application
3156 to connect to the port before continuing, unless the @code{nowait}
3157 option was specified. The @code{nodelay} option disables the Nagle buffering
3158 algorithm. The @code{reconnect} option only applies if @var{noserver} is
3159 set, if the connection goes down it will attempt to reconnect at the
3160 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
3161 one TCP connection at a time is accepted. You can use @code{telnet} to
3162 connect to the corresponding character device.
3163 @table @code
3164 @item Example to send tcp console to 192.168.0.2 port 4444
3165 -serial tcp:192.168.0.2:4444
3166 @item Example to listen and wait on port 4444 for connection
3167 -serial tcp::4444,server
3168 @item Example to not wait and listen on ip 192.168.0.100 port 4444
3169 -serial tcp:192.168.0.100:4444,server,nowait
3170 @end table
3172 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3173 The telnet protocol is used instead of raw tcp sockets. The options
3174 work the same as if you had specified @code{-serial tcp}. The
3175 difference is that the port acts like a telnet server or client using
3176 telnet option negotiation. This will also allow you to send the
3177 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3178 sequence. Typically in unix telnet you do it with Control-] and then
3179 type "send break" followed by pressing the enter key.
3181 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3182 A unix domain socket is used instead of a tcp socket. The option works the
3183 same as if you had specified @code{-serial tcp} except the unix domain socket
3184 @var{path} is used for connections.
3186 @item mon:@var{dev_string}
3187 This is a special option to allow the monitor to be multiplexed onto
3188 another serial port. The monitor is accessed with key sequence of
3189 @key{Control-a} and then pressing @key{c}.
3190 @var{dev_string} should be any one of the serial devices specified
3191 above. An example to multiplex the monitor onto a telnet server
3192 listening on port 4444 would be:
3193 @table @code
3194 @item -serial mon:telnet::4444,server,nowait
3195 @end table
3196 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3197 QEMU any more but will be passed to the guest instead.
3199 @item braille
3200 Braille device. This will use BrlAPI to display the braille output on a real
3201 or fake device.
3203 @item msmouse
3204 Three button serial mouse. Configure the guest to use Microsoft protocol.
3205 @end table
3206 ETEXI
3208 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3209 "-parallel dev redirect the parallel port to char device 'dev'\n",
3210 QEMU_ARCH_ALL)
3211 STEXI
3212 @item -parallel @var{dev}
3213 @findex -parallel
3214 Redirect the virtual parallel port to host device @var{dev} (same
3215 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3216 be used to use hardware devices connected on the corresponding host
3217 parallel port.
3219 This option can be used several times to simulate up to 3 parallel
3220 ports.
3222 Use @code{-parallel none} to disable all parallel ports.
3223 ETEXI
3225 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3226 "-monitor dev redirect the monitor to char device 'dev'\n",
3227 QEMU_ARCH_ALL)
3228 STEXI
3229 @item -monitor @var{dev}
3230 @findex -monitor
3231 Redirect the monitor to host device @var{dev} (same devices as the
3232 serial port).
3233 The default device is @code{vc} in graphical mode and @code{stdio} in
3234 non graphical mode.
3235 Use @code{-monitor none} to disable the default monitor.
3236 ETEXI
3237 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3238 "-qmp dev like -monitor but opens in 'control' mode\n",
3239 QEMU_ARCH_ALL)
3240 STEXI
3241 @item -qmp @var{dev}
3242 @findex -qmp
3243 Like -monitor but opens in 'control' mode.
3244 ETEXI
3245 DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3246 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3247 QEMU_ARCH_ALL)
3248 STEXI
3249 @item -qmp-pretty @var{dev}
3250 @findex -qmp-pretty
3251 Like -qmp but uses pretty JSON formatting.
3252 ETEXI
3254 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3255 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL)
3256 STEXI
3257 @item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]
3258 @findex -mon
3259 Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing
3260 easing human reading and debugging.
3261 ETEXI
3263 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3264 "-debugcon dev redirect the debug console to char device 'dev'\n",
3265 QEMU_ARCH_ALL)
3266 STEXI
3267 @item -debugcon @var{dev}
3268 @findex -debugcon
3269 Redirect the debug console to host device @var{dev} (same devices as the
3270 serial port). The debug console is an I/O port which is typically port
3271 0xe9; writing to that I/O port sends output to this device.
3272 The default device is @code{vc} in graphical mode and @code{stdio} in
3273 non graphical mode.
3274 ETEXI
3276 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3277 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
3278 STEXI
3279 @item -pidfile @var{file}
3280 @findex -pidfile
3281 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3282 from a script.
3283 ETEXI
3285 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3286 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
3287 STEXI
3288 @item -singlestep
3289 @findex -singlestep
3290 Run the emulation in single step mode.
3291 ETEXI
3293 DEF("preconfig", 0, QEMU_OPTION_preconfig, \
3294 "--preconfig pause QEMU before machine is initialized\n",
3295 QEMU_ARCH_ALL)
3296 STEXI
3297 @item --preconfig
3298 @findex --preconfig
3299 Pause QEMU for interactive configuration before the machine is created,
3300 which allows querying and configuring properties that will affect
3301 machine initialization. Use the QMP command 'exit-preconfig' to exit
3302 the preconfig state and move to the next state (ie. run guest if -S
3303 isn't used or pause the second time if -S is used).
3304 ETEXI
3306 DEF("S", 0, QEMU_OPTION_S, \
3307 "-S freeze CPU at startup (use 'c' to start execution)\n",
3308 QEMU_ARCH_ALL)
3309 STEXI
3310 @item -S
3311 @findex -S
3312 Do not start CPU at startup (you must type 'c' in the monitor).
3313 ETEXI
3315 DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3316 "-realtime [mlock=on|off]\n"
3317 " run qemu with realtime features\n"
3318 " mlock=on|off controls mlock support (default: on)\n",
3319 QEMU_ARCH_ALL)
3320 STEXI
3321 @item -realtime mlock=on|off
3322 @findex -realtime
3323 Run qemu with realtime features.
3324 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3325 (enabled by default).
3326 ETEXI
3328 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3329 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3330 STEXI
3331 @item -gdb @var{dev}
3332 @findex -gdb
3333 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3334 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3335 stdio are reasonable use case. The latter is allowing to start QEMU from
3336 within gdb and establish the connection via a pipe:
3337 @example
3338 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3339 @end example
3340 ETEXI
3342 DEF("s", 0, QEMU_OPTION_s, \
3343 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3344 QEMU_ARCH_ALL)
3345 STEXI
3346 @item -s
3347 @findex -s
3348 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3349 (@pxref{gdb_usage}).
3350 ETEXI
3352 DEF("d", HAS_ARG, QEMU_OPTION_d, \
3353 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
3354 QEMU_ARCH_ALL)
3355 STEXI
3356 @item -d @var{item1}[,...]
3357 @findex -d
3358 Enable logging of specified items. Use '-d help' for a list of log items.
3359 ETEXI
3361 DEF("D", HAS_ARG, QEMU_OPTION_D, \
3362 "-D logfile output log to logfile (default stderr)\n",
3363 QEMU_ARCH_ALL)
3364 STEXI
3365 @item -D @var{logfile}
3366 @findex -D
3367 Output log in @var{logfile} instead of to stderr
3368 ETEXI
3370 DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3371 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3372 QEMU_ARCH_ALL)
3373 STEXI
3374 @item -dfilter @var{range1}[,...]
3375 @findex -dfilter
3376 Filter debug output to that relevant to a range of target addresses. The filter
3377 spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3378 @var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3379 addresses and sizes required. For example:
3380 @example
3381 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3382 @end example
3383 Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3384 the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3385 block starting at 0xffffffc00005f000.
3386 ETEXI
3388 DEF("L", HAS_ARG, QEMU_OPTION_L, \
3389 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
3390 QEMU_ARCH_ALL)
3391 STEXI
3392 @item -L @var{path}
3393 @findex -L
3394 Set the directory for the BIOS, VGA BIOS and keymaps.
3396 To list all the data directories, use @code{-L help}.
3397 ETEXI
3399 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3400 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
3401 STEXI
3402 @item -bios @var{file}
3403 @findex -bios
3404 Set the filename for the BIOS.
3405 ETEXI
3407 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3408 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3409 STEXI
3410 @item -enable-kvm
3411 @findex -enable-kvm
3412 Enable KVM full virtualization support. This option is only available
3413 if KVM support is enabled when compiling.
3414 ETEXI
3416 DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3417 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386)
3418 STEXI
3419 @item -enable-hax
3420 @findex -enable-hax
3421 Enable HAX (Hardware-based Acceleration eXecution) support. This option
3422 is only available if HAX support is enabled when compiling. HAX is only
3423 applicable to MAC and Windows platform, and thus does not conflict with
3424 KVM.
3425 ETEXI
3427 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3428 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
3429 DEF("xen-create", 0, QEMU_OPTION_xen_create,
3430 "-xen-create create domain using xen hypercalls, bypassing xend\n"
3431 " warning: should not be used when xend is in use\n",
3432 QEMU_ARCH_ALL)
3433 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3434 "-xen-attach attach to existing xen domain\n"
3435 " xend will use this when starting QEMU\n",
3436 QEMU_ARCH_ALL)
3437 DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
3438 "-xen-domid-restrict restrict set of available xen operations\n"
3439 " to specified domain id. (Does not affect\n"
3440 " xenpv machine type).\n",
3441 QEMU_ARCH_ALL)
3442 STEXI
3443 @item -xen-domid @var{id}
3444 @findex -xen-domid
3445 Specify xen guest domain @var{id} (XEN only).
3446 @item -xen-create
3447 @findex -xen-create
3448 Create domain using xen hypercalls, bypassing xend.
3449 Warning: should not be used when xend is in use (XEN only).
3450 @item -xen-attach
3451 @findex -xen-attach
3452 Attach to existing xen domain.
3453 xend will use this when starting QEMU (XEN only).
3454 @findex -xen-domid-restrict
3455 Restrict set of available xen operations to specified domain id (XEN only).
3456 ETEXI
3458 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3459 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
3460 STEXI
3461 @item -no-reboot
3462 @findex -no-reboot
3463 Exit instead of rebooting.
3464 ETEXI
3466 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3467 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
3468 STEXI
3469 @item -no-shutdown
3470 @findex -no-shutdown
3471 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3472 This allows for instance switching to monitor to commit changes to the
3473 disk image.
3474 ETEXI
3476 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3477 "-loadvm [tag|id]\n" \
3478 " start right away with a saved state (loadvm in monitor)\n",
3479 QEMU_ARCH_ALL)
3480 STEXI
3481 @item -loadvm @var{file}
3482 @findex -loadvm
3483 Start right away with a saved state (@code{loadvm} in monitor)
3484 ETEXI
3486 #ifndef _WIN32
3487 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3488 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3489 #endif
3490 STEXI
3491 @item -daemonize
3492 @findex -daemonize
3493 Daemonize the QEMU process after initialization. QEMU will not detach from
3494 standard IO until it is ready to receive connections on any of its devices.
3495 This option is a useful way for external programs to launch QEMU without having
3496 to cope with initialization race conditions.
3497 ETEXI
3499 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3500 "-option-rom rom load a file, rom, into the option ROM space\n",
3501 QEMU_ARCH_ALL)
3502 STEXI
3503 @item -option-rom @var{file}
3504 @findex -option-rom
3505 Load the contents of @var{file} as an option ROM.
3506 This option is useful to load things like EtherBoot.
3507 ETEXI
3509 HXCOMM Silently ignored for compatibility
3510 DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3512 HXCOMM Options deprecated by -rtc
3513 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3514 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3516 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3517 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3518 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3519 QEMU_ARCH_ALL)
3521 STEXI
3523 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3524 @findex -rtc
3525 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3526 UTC or local time, respectively. @code{localtime} is required for correct date in
3527 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3528 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3530 By default the RTC is driven by the host system time. This allows using of the
3531 RTC as accurate reference clock inside the guest, specifically if the host
3532 time is smoothly following an accurate external reference clock, e.g. via NTP.
3533 If you want to isolate the guest time from the host, you can set @option{clock}
3534 to @code{rt} instead. To even prevent it from progressing during suspension,
3535 you can set it to @code{vm}.
3537 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3538 specifically with Windows' ACPI HAL. This option will try to figure out how
3539 many timer interrupts were not processed by the Windows guest and will
3540 re-inject them.
3541 ETEXI
3543 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3544 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3545 " enable virtual instruction counter with 2^N clock ticks per\n" \
3546 " instruction, enable aligning the host and virtual clocks\n" \
3547 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3548 STEXI
3549 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3550 @findex -icount
3551 Enable virtual instruction counter. The virtual cpu will execute one
3552 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3553 then the virtual cpu speed will be automatically adjusted to keep virtual
3554 time within a few seconds of real time.
3556 When the virtual cpu is sleeping, the virtual time will advance at default
3557 speed unless @option{sleep=on|off} is specified.
3558 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3559 instantly whenever the virtual cpu goes to sleep mode and will not advance
3560 if no timer is enabled. This behavior give deterministic execution times from
3561 the guest point of view.
3563 Note that while this option can give deterministic behavior, it does not
3564 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3565 order cores with complex cache hierarchies. The number of instructions
3566 executed often has little or no correlation with actual performance.
3568 @option{align=on} will activate the delay algorithm which will try
3569 to synchronise the host clock and the virtual clock. The goal is to
3570 have a guest running at the real frequency imposed by the shift option.
3571 Whenever the guest clock is behind the host clock and if
3572 @option{align=on} is specified then we print a message to the user
3573 to inform about the delay.
3574 Currently this option does not work when @option{shift} is @code{auto}.
3575 Note: The sync algorithm will work for those shift values for which
3576 the guest clock runs ahead of the host clock. Typically this happens
3577 when the shift value is high (how high depends on the host machine).
3579 When @option{rr} option is specified deterministic record/replay is enabled.
3580 Replay log is written into @var{filename} file in record mode and
3581 read from this file in replay mode.
3583 Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3584 at the start of execution recording. In replay mode this option is used
3585 to load the initial VM state.
3586 ETEXI
3588 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3589 "-watchdog model\n" \
3590 " enable virtual hardware watchdog [default=none]\n",
3591 QEMU_ARCH_ALL)
3592 STEXI
3593 @item -watchdog @var{model}
3594 @findex -watchdog
3595 Create a virtual hardware watchdog device. Once enabled (by a guest
3596 action), the watchdog must be periodically polled by an agent inside
3597 the guest or else the guest will be restarted. Choose a model for
3598 which your guest has drivers.
3600 The @var{model} is the model of hardware watchdog to emulate. Use
3601 @code{-watchdog help} to list available hardware models. Only one
3602 watchdog can be enabled for a guest.
3604 The following models may be available:
3605 @table @option
3606 @item ib700
3607 iBASE 700 is a very simple ISA watchdog with a single timer.
3608 @item i6300esb
3609 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3610 dual-timer watchdog.
3611 @item diag288
3612 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3613 (currently KVM only).
3614 @end table
3615 ETEXI
3617 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3618 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \
3619 " action when watchdog fires [default=reset]\n",
3620 QEMU_ARCH_ALL)
3621 STEXI
3622 @item -watchdog-action @var{action}
3623 @findex -watchdog-action
3625 The @var{action} controls what QEMU will do when the watchdog timer
3626 expires.
3627 The default is
3628 @code{reset} (forcefully reset the guest).
3629 Other possible actions are:
3630 @code{shutdown} (attempt to gracefully shutdown the guest),
3631 @code{poweroff} (forcefully poweroff the guest),
3632 @code{inject-nmi} (inject a NMI into the guest),
3633 @code{pause} (pause the guest),
3634 @code{debug} (print a debug message and continue), or
3635 @code{none} (do nothing).
3637 Note that the @code{shutdown} action requires that the guest responds
3638 to ACPI signals, which it may not be able to do in the sort of
3639 situations where the watchdog would have expired, and thus
3640 @code{-watchdog-action shutdown} is not recommended for production use.
3642 Examples:
3644 @table @code
3645 @item -watchdog i6300esb -watchdog-action pause
3646 @itemx -watchdog ib700
3647 @end table
3648 ETEXI
3650 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3651 "-echr chr set terminal escape character instead of ctrl-a\n",
3652 QEMU_ARCH_ALL)
3653 STEXI
3655 @item -echr @var{numeric_ascii_value}
3656 @findex -echr
3657 Change the escape character used for switching to the monitor when using
3658 monitor and serial sharing. The default is @code{0x01} when using the
3659 @code{-nographic} option. @code{0x01} is equal to pressing
3660 @code{Control-a}. You can select a different character from the ascii
3661 control keys where 1 through 26 map to Control-a through Control-z. For
3662 instance you could use the either of the following to change the escape
3663 character to Control-t.
3664 @table @code
3665 @item -echr 0x14
3666 @itemx -echr 20
3667 @end table
3668 ETEXI
3670 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3671 "-virtioconsole c\n" \
3672 " set virtio console\n", QEMU_ARCH_ALL)
3673 STEXI
3674 @item -virtioconsole @var{c}
3675 @findex -virtioconsole
3676 Set virtio console.
3677 This option is deprecated, please use @option{-device virtconsole} instead.
3678 ETEXI
3680 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3681 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3682 STEXI
3683 @item -show-cursor
3684 @findex -show-cursor
3685 Show cursor.
3686 ETEXI
3688 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3689 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3690 STEXI
3691 @item -tb-size @var{n}
3692 @findex -tb-size
3693 Set TB size.
3694 ETEXI
3696 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3697 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3698 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3699 "-incoming unix:socketpath\n" \
3700 " prepare for incoming migration, listen on\n" \
3701 " specified protocol and socket address\n" \
3702 "-incoming fd:fd\n" \
3703 "-incoming exec:cmdline\n" \
3704 " accept incoming migration on given file descriptor\n" \
3705 " or from given external command\n" \
3706 "-incoming defer\n" \
3707 " wait for the URI to be specified via migrate_incoming\n",
3708 QEMU_ARCH_ALL)
3709 STEXI
3710 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3711 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3712 @findex -incoming
3713 Prepare for incoming migration, listen on a given tcp port.
3715 @item -incoming unix:@var{socketpath}
3716 Prepare for incoming migration, listen on a given unix socket.
3718 @item -incoming fd:@var{fd}
3719 Accept incoming migration from a given filedescriptor.
3721 @item -incoming exec:@var{cmdline}
3722 Accept incoming migration as an output from specified external command.
3724 @item -incoming defer
3725 Wait for the URI to be specified via migrate_incoming. The monitor can
3726 be used to change settings (such as migration parameters) prior to issuing
3727 the migrate_incoming to allow the migration to begin.
3728 ETEXI
3730 DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \
3731 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL)
3732 STEXI
3733 @item -only-migratable
3734 @findex -only-migratable
3735 Only allow migratable devices. Devices will not be allowed to enter an
3736 unmigratable state.
3737 ETEXI
3739 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3740 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
3741 STEXI
3742 @item -nodefaults
3743 @findex -nodefaults
3744 Don't create default devices. Normally, QEMU sets the default devices like serial
3745 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3746 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3747 default devices.
3748 ETEXI
3750 #ifndef _WIN32
3751 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3752 "-chroot dir chroot to dir just before starting the VM\n",
3753 QEMU_ARCH_ALL)
3754 #endif
3755 STEXI
3756 @item -chroot @var{dir}
3757 @findex -chroot
3758 Immediately before starting guest execution, chroot to the specified
3759 directory. Especially useful in combination with -runas.
3760 ETEXI
3762 #ifndef _WIN32
3763 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3764 "-runas user change to user id user just before starting the VM\n" \
3765 " user can be numeric uid:gid instead\n",
3766 QEMU_ARCH_ALL)
3767 #endif
3768 STEXI
3769 @item -runas @var{user}
3770 @findex -runas
3771 Immediately before starting guest execution, drop root privileges, switching
3772 to the specified user.
3773 ETEXI
3775 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3776 "-prom-env variable=value\n"
3777 " set OpenBIOS nvram variables\n",
3778 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3779 STEXI
3780 @item -prom-env @var{variable}=@var{value}
3781 @findex -prom-env
3782 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3783 ETEXI
3784 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3785 "-semihosting semihosting mode\n",
3786 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3787 QEMU_ARCH_MIPS)
3788 STEXI
3789 @item -semihosting
3790 @findex -semihosting
3791 Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3792 ETEXI
3793 DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3794 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3795 " semihosting configuration\n",
3796 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3797 QEMU_ARCH_MIPS)
3798 STEXI
3799 @item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3800 @findex -semihosting-config
3801 Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3802 @table @option
3803 @item target=@code{native|gdb|auto}
3804 Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3805 or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3806 during debug sessions and @code{native} otherwise.
3807 @item arg=@var{str1},arg=@var{str2},...
3808 Allows the user to pass input arguments, and can be used multiple times to build
3809 up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3810 command line is still supported for backward compatibility. If both the
3811 @code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3812 specified, the former is passed to semihosting as it always takes precedence.
3813 @end table
3814 ETEXI
3815 DEF("old-param", 0, QEMU_OPTION_old_param,
3816 "-old-param old param mode\n", QEMU_ARCH_ARM)
3817 STEXI
3818 @item -old-param
3819 @findex -old-param (ARM)
3820 Old param mode (ARM only).
3821 ETEXI
3823 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3824 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
3825 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
3826 " Enable seccomp mode 2 system call filter (default 'off').\n" \
3827 " use 'obsolete' to allow obsolete system calls that are provided\n" \
3828 " by the kernel, but typically no longer used by modern\n" \
3829 " C library implementations.\n" \
3830 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \
3831 " its privileges by blacklisting all set*uid|gid system calls.\n" \
3832 " The value 'children' will deny set*uid|gid system calls for\n" \
3833 " main QEMU process but will allow forks and execves to run unprivileged\n" \
3834 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \
3835 " blacklisting *fork and execve\n" \
3836 " use 'resourcecontrol' to disable process affinity and schedular priority\n",
3837 QEMU_ARCH_ALL)
3838 STEXI
3839 @item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
3840 @findex -sandbox
3841 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3842 disable it. The default is 'off'.
3843 @table @option
3844 @item obsolete=@var{string}
3845 Enable Obsolete system calls
3846 @item elevateprivileges=@var{string}
3847 Disable set*uid|gid system calls
3848 @item spawn=@var{string}
3849 Disable *fork and execve
3850 @item resourcecontrol=@var{string}
3851 Disable process affinity and schedular priority
3852 @end table
3853 ETEXI
3855 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3856 "-readconfig <file>\n", QEMU_ARCH_ALL)
3857 STEXI
3858 @item -readconfig @var{file}
3859 @findex -readconfig
3860 Read device configuration from @var{file}. This approach is useful when you want to spawn
3861 QEMU process with many command line options but you don't want to exceed the command line
3862 character limit.
3863 ETEXI
3864 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3865 "-writeconfig <file>\n"
3866 " read/write config file\n", QEMU_ARCH_ALL)
3867 STEXI
3868 @item -writeconfig @var{file}
3869 @findex -writeconfig
3870 Write device configuration to @var{file}. The @var{file} can be either filename to save
3871 command line and device configuration into file or dash @code{-}) character to print the
3872 output to stdout. This can be later used as input file for @code{-readconfig} option.
3873 ETEXI
3874 HXCOMM Deprecated, same as -no-user-config
3875 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
3876 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3877 "-no-user-config\n"
3878 " do not load default user-provided config files at startup\n",
3879 QEMU_ARCH_ALL)
3880 STEXI
3881 @item -no-user-config
3882 @findex -no-user-config
3883 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3884 config files on @var{sysconfdir}.
3885 ETEXI
3886 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3887 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3888 " specify tracing options\n",
3889 QEMU_ARCH_ALL)
3890 STEXI
3891 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3892 HXCOMM HX does not support conditional compilation of text.
3893 @item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
3894 @findex -trace
3895 @include qemu-option-trace.texi
3896 ETEXI
3898 HXCOMM Internal use
3899 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3900 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3902 #ifdef __linux__
3903 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3904 "-enable-fips enable FIPS 140-2 compliance\n",
3905 QEMU_ARCH_ALL)
3906 #endif
3907 STEXI
3908 @item -enable-fips
3909 @findex -enable-fips
3910 Enable FIPS 140-2 compliance mode.
3911 ETEXI
3913 HXCOMM Deprecated by -machine accel=tcg property
3914 DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3916 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3917 "-msg timestamp[=on|off]\n"
3918 " change the format of messages\n"
3919 " on|off controls leading timestamps (default:on)\n",
3920 QEMU_ARCH_ALL)
3921 STEXI
3922 @item -msg timestamp[=on|off]
3923 @findex -msg
3924 prepend a timestamp to each log message.(default:on)
3925 ETEXI
3927 DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3928 "-dump-vmstate <file>\n"
3929 " Output vmstate information in JSON format to file.\n"
3930 " Use the scripts/vmstate-static-checker.py file to\n"
3931 " check for possible regressions in migration code\n"
3932 " by comparing two such vmstate dumps.\n",
3933 QEMU_ARCH_ALL)
3934 STEXI
3935 @item -dump-vmstate @var{file}
3936 @findex -dump-vmstate
3937 Dump json-encoded vmstate information for current machine type to file
3938 in @var{file}
3939 ETEXI
3941 STEXI
3942 @end table
3943 ETEXI
3944 DEFHEADING()
3946 DEFHEADING(Generic object creation:)
3947 STEXI
3948 @table @option
3949 ETEXI
3951 DEF("object", HAS_ARG, QEMU_OPTION_object,
3952 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3953 " create a new object of type TYPENAME setting properties\n"
3954 " in the order they are specified. Note that the 'id'\n"
3955 " property must be set. These objects are placed in the\n"
3956 " '/objects' path.\n",
3957 QEMU_ARCH_ALL)
3958 STEXI
3959 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3960 @findex -object
3961 Create a new object of type @var{typename} setting properties
3962 in the order they are specified. Note that the 'id'
3963 property must be set. These objects are placed in the
3964 '/objects' path.
3966 @table @option
3968 @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}
3970 Creates a memory file backend object, which can be used to back
3971 the guest RAM with huge pages.
3973 The @option{id} parameter is a unique ID that will be used to reference this
3974 memory region when configuring the @option{-numa} argument.
3976 The @option{size} option provides the size of the memory region, and accepts
3977 common suffixes, eg @option{500M}.
3979 The @option{mem-path} provides the path to either a shared memory or huge page
3980 filesystem mount.
3982 The @option{share} boolean option determines whether the memory
3983 region is marked as private to QEMU, or shared. The latter allows
3984 a co-operating external process to access the QEMU memory region.
3986 The @option{share} is also required for pvrdma devices due to
3987 limitations in the RDMA API provided by Linux.
3989 Setting share=on might affect the ability to configure NUMA
3990 bindings for the memory backend under some circumstances, see
3991 Documentation/vm/numa_memory_policy.txt on the Linux kernel
3992 source tree for additional details.
3994 Setting the @option{discard-data} boolean option to @var{on}
3995 indicates that file contents can be destroyed when QEMU exits,
3996 to avoid unnecessarily flushing data to the backing file. Note
3997 that @option{discard-data} is only an optimization, and QEMU
3998 might not discard file contents if it aborts unexpectedly or is
3999 terminated using SIGKILL.
4001 The @option{merge} boolean option enables memory merge, also known as
4002 MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for
4003 memory deduplication.
4005 Setting the @option{dump} boolean option to @var{off} excludes the memory from
4006 core dumps. This feature is also known as MADV_DONTDUMP.
4008 The @option{prealloc} boolean option enables memory preallocation.
4010 The @option{host-nodes} option binds the memory range to a list of NUMA host
4011 nodes.
4013 The @option{policy} option sets the NUMA policy to one of the following values:
4015 @table @option
4016 @item @var{default}
4017 default host policy
4019 @item @var{preferred}
4020 prefer the given host node list for allocation
4022 @item @var{bind}
4023 restrict memory allocation to the given host node list
4025 @item @var{interleave}
4026 interleave memory allocations across the given host node list
4027 @end table
4029 The @option{align} option specifies the base address alignment when
4030 QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg
4031 @option{2M}. Some backend store specified by @option{mem-path}
4032 requires an alignment different than the default one used by QEMU, eg
4033 the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In
4034 such cases, users can specify the required alignment via this option.
4036 @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}
4038 Creates a memory backend object, which can be used to back the guest RAM.
4039 Memory backend objects offer more control than the @option{-m} option that is
4040 traditionally used to define guest RAM. Please refer to
4041 @option{memory-backend-file} for a description of the options.
4043 @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}
4045 Creates an anonymous memory file backend object, which allows QEMU to
4046 share the memory with an external process (e.g. when using
4047 vhost-user). The memory is allocated with memfd and optional
4048 sealing. (Linux only)
4050 The @option{seal} option creates a sealed-file, that will block
4051 further resizing the memory ('on' by default).
4053 The @option{hugetlb} option specify the file to be created resides in
4054 the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with
4055 the @option{hugetlb} option, the @option{hugetlbsize} option specify
4056 the hugetlb page size on systems that support multiple hugetlb page
4057 sizes (it must be a power of 2 value supported by the system).
4059 In some versions of Linux, the @option{hugetlb} option is incompatible
4060 with the @option{seal} option (requires at least Linux 4.16).
4062 Please refer to @option{memory-backend-file} for a description of the
4063 other options.
4065 @item -object rng-random,id=@var{id},filename=@var{/dev/random}
4067 Creates a random number generator backend which obtains entropy from
4068 a device on the host. The @option{id} parameter is a unique ID that
4069 will be used to reference this entropy backend from the @option{virtio-rng}
4070 device. The @option{filename} parameter specifies which file to obtain
4071 entropy from and if omitted defaults to @option{/dev/random}.
4073 @item -object rng-egd,id=@var{id},chardev=@var{chardevid}
4075 Creates a random number generator backend which obtains entropy from
4076 an external daemon running on the host. The @option{id} parameter is
4077 a unique ID that will be used to reference this entropy backend from
4078 the @option{virtio-rng} device. The @option{chardev} parameter is
4079 the unique ID of a character device backend that provides the connection
4080 to the RNG daemon.
4082 @item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
4084 Creates a TLS anonymous credentials object, which can be used to provide
4085 TLS support on network backends. The @option{id} parameter is a unique
4086 ID which network backends will use to access the credentials. The
4087 @option{endpoint} is either @option{server} or @option{client} depending
4088 on whether the QEMU network backend that uses the credentials will be
4089 acting as a client or as a server. If @option{verify-peer} is enabled
4090 (the default) then once the handshake is completed, the peer credentials
4091 will be verified, though this is a no-op for anonymous credentials.
4093 The @var{dir} parameter tells QEMU where to find the credential
4094 files. For server endpoints, this directory may contain a file
4095 @var{dh-params.pem} providing diffie-hellman parameters to use
4096 for the TLS server. If the file is missing, QEMU will generate
4097 a set of DH parameters at startup. This is a computationally
4098 expensive operation that consumes random pool entropy, so it is
4099 recommended that a persistent set of parameters be generated
4100 upfront and saved.
4102 @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}
4104 Creates a TLS anonymous credentials object, which can be used to provide
4105 TLS support on network backends. The @option{id} parameter is a unique
4106 ID which network backends will use to access the credentials. The
4107 @option{endpoint} is either @option{server} or @option{client} depending
4108 on whether the QEMU network backend that uses the credentials will be
4109 acting as a client or as a server. If @option{verify-peer} is enabled
4110 (the default) then once the handshake is completed, the peer credentials
4111 will be verified. With x509 certificates, this implies that the clients
4112 must be provided with valid client certificates too.
4114 The @var{dir} parameter tells QEMU where to find the credential
4115 files. For server endpoints, this directory may contain a file
4116 @var{dh-params.pem} providing diffie-hellman parameters to use
4117 for the TLS server. If the file is missing, QEMU will generate
4118 a set of DH parameters at startup. This is a computationally
4119 expensive operation that consumes random pool entropy, so it is
4120 recommended that a persistent set of parameters be generated
4121 upfront and saved.
4123 For x509 certificate credentials the directory will contain further files
4124 providing the x509 certificates. The certificates must be stored
4125 in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
4126 @var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
4127 @var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
4129 For the @var{server-key.pem} and @var{client-key.pem} files which
4130 contain sensitive private keys, it is possible to use an encrypted
4131 version by providing the @var{passwordid} parameter. This provides
4132 the ID of a previously created @code{secret} object containing the
4133 password for decryption.
4135 The @var{priority} parameter allows to override the global default
4136 priority used by gnutls. This can be useful if the system administrator
4137 needs to use a weaker set of crypto priorities for QEMU without
4138 potentially forcing the weakness onto all applications. Or conversely
4139 if one wants wants a stronger default for QEMU than for all other
4140 applications, they can do this through this parameter. Its format is
4141 a gnutls priority string as described at
4142 @url{https://gnutls.org/manual/html_node/Priority-Strings.html}.
4144 @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
4146 Interval @var{t} can't be 0, this filter batches the packet delivery: all
4147 packets arriving in a given interval on netdev @var{netdevid} are delayed
4148 until the end of the interval. Interval is in microseconds.
4149 @option{status} is optional that indicate whether the netfilter is
4150 on (enabled) or off (disabled), the default status for netfilter will be 'on'.
4152 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4154 @option{all}: the filter is attached both to the receive and the transmit
4155 queue of the netdev (default).
4157 @option{rx}: the filter is attached to the receive queue of the netdev,
4158 where it will receive packets sent to the netdev.
4160 @option{tx}: the filter is attached to the transmit queue of the netdev,
4161 where it will receive packets sent by the netdev.
4163 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4165 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.
4167 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4169 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4170 @var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
4171 filter-redirector will redirect packet with vnet_hdr_len.
4172 Create a filter-redirector we need to differ outdev id from indev id, id can not
4173 be the same. we can just use indev or outdev, but at least one of indev or outdev
4174 need to be specified.
4176 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4178 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4179 secondary from primary to keep secondary tcp connection,and rewrite
4180 tcp packet to primary from secondary make tcp packet can be handled by
4181 client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4183 usage:
4184 colo secondary:
4185 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4186 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4187 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
4189 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4191 Dump the network traffic on netdev @var{dev} to the file specified by
4192 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4193 The file format is libpcap, so it can be analyzed with tools such as tcpdump
4194 or Wireshark.
4196 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4198 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4199 secondary packet. If the packets are same, we will output primary
4200 packet to outdev@var{chardevid}, else we will notify colo-frame
4201 do checkpoint and send primary packet to outdev@var{chardevid}.
4202 if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4204 we must use it with the help of filter-mirror and filter-redirector.
4206 @example
4208 primary:
4209 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4210 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4211 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4212 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4213 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4214 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4215 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4216 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4217 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4218 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4219 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4220 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4222 secondary:
4223 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4224 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4225 -chardev socket,id=red0,host=3.3.3.3,port=9003
4226 -chardev socket,id=red1,host=3.3.3.3,port=9004
4227 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4228 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4230 @end example
4232 If you want to know the detail of above command line, you can read
4233 the colo-compare git log.
4235 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4237 Creates a cryptodev backend which executes crypto opreation from
4238 the QEMU cipher APIS. The @var{id} parameter is
4239 a unique ID that will be used to reference this cryptodev backend from
4240 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4241 which specify the queue number of cryptodev backend, the default of
4242 @var{queues} is 1.
4244 @example
4246 # qemu-system-x86_64 \
4247 [...] \
4248 -object cryptodev-backend-builtin,id=cryptodev0 \
4249 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4250 [...]
4251 @end example
4253 @item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}]
4255 Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}.
4256 The @var{id} parameter is a unique ID that will be used to reference this
4257 cryptodev backend from the @option{virtio-crypto} device.
4258 The chardev should be a unix domain socket backed one. The vhost-user uses
4259 a specifically defined protocol to pass vhost ioctl replacement messages
4260 to an application on the other end of the socket.
4261 The @var{queues} parameter is optional, which specify the queue number
4262 of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1.
4264 @example
4266 # qemu-system-x86_64 \
4267 [...] \
4268 -chardev socket,id=chardev0,path=/path/to/socket \
4269 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \
4270 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4271 [...]
4272 @end example
4274 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4275 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4277 Defines a secret to store a password, encryption key, or some other sensitive
4278 data. The sensitive data can either be passed directly via the @var{data}
4279 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4280 parameter is insecure unless the sensitive data is encrypted.
4282 The sensitive data can be provided in raw format (the default), or base64.
4283 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4284 so base64 is recommended for sending binary data. QEMU will convert from
4285 which ever format is provided to the format it needs internally. eg, an
4286 RBD password can be provided in raw format, even though it will be base64
4287 encoded when passed onto the RBD sever.
4289 For added protection, it is possible to encrypt the data associated with
4290 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4291 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4292 parameter provides the ID of a previously defined secret that contains
4293 the AES-256 decryption key. This key should be 32-bytes long and be
4294 base64 encoded. The @var{iv} parameter provides the random initialization
4295 vector used for encryption of this particular secret and should be a
4296 base64 encrypted string of the 16-byte IV.
4298 The simplest (insecure) usage is to provide the secret inline
4300 @example
4302 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4304 @end example
4306 The simplest secure usage is to provide the secret via a file
4308 # printf "letmein" > mypasswd.txt
4309 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4311 For greater security, AES-256-CBC should be used. To illustrate usage,
4312 consider the openssl command line tool which can encrypt the data. Note
4313 that when encrypting, the plaintext must be padded to the cipher block
4314 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4316 First a master key needs to be created in base64 encoding:
4318 @example
4319 # openssl rand -base64 32 > key.b64
4320 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
4321 @end example
4323 Each secret to be encrypted needs to have a random initialization vector
4324 generated. These do not need to be kept secret
4326 @example
4327 # openssl rand -base64 16 > iv.b64
4328 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
4329 @end example
4331 The secret to be defined can now be encrypted, in this case we're
4332 telling openssl to base64 encode the result, but it could be left
4333 as raw bytes if desired.
4335 @example
4336 # SECRET=$(printf "letmein" |
4337 openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4338 @end example
4340 When launching QEMU, create a master secret pointing to @code{key.b64}
4341 and specify that to be used to decrypt the user password. Pass the
4342 contents of @code{iv.b64} to the second secret
4344 @example
4345 # $QEMU \
4346 -object secret,id=secmaster0,format=base64,file=key.b64 \
4347 -object secret,id=sec0,keyid=secmaster0,format=base64,\
4348 data=$SECRET,iv=$(<iv.b64)
4349 @end example
4351 @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}]
4353 Create a Secure Encrypted Virtualization (SEV) guest object, which can be used
4354 to provide the guest memory encryption support on AMD processors.
4356 When memory encryption is enabled, one of the physical address bit (aka the
4357 C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos}
4358 is used to provide the C-bit position. The C-bit position is Host family dependent
4359 hence user must provide this value. On EPYC, the value should be 47.
4361 When memory encryption is enabled, we loose certain bits in physical address space.
4362 The @option{reduced-phys-bits} is used to provide the number of bits we loose in
4363 physical address space. Similar to C-bit, the value is Host family dependent.
4364 On EPYC, the value should be 5.
4366 The @option{sev-device} provides the device file to use for communicating with
4367 the SEV firmware running inside AMD Secure Processor. The default device is
4368 '/dev/sev'. If hardware supports memory encryption then /dev/sev devices are
4369 created by CCP driver.
4371 The @option{policy} provides the guest policy to be enforced by the SEV firmware
4372 and restrict what configuration and operational commands can be performed on this
4373 guest by the hypervisor. The policy should be provided by the guest owner and is
4374 bound to the guest and cannot be changed throughout the lifetime of the guest.
4375 The default is 0.
4377 If guest @option{policy} allows sharing the key with another SEV guest then
4378 @option{handle} can be use to provide handle of the guest from which to share
4379 the key.
4381 The @option{dh-cert-file} and @option{session-file} provides the guest owner's
4382 Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters
4383 are used for establishing a cryptographic session with the guest owner to
4384 negotiate keys used for attestation. The file must be encoded in base64.
4386 e.g to launch a SEV guest
4387 @example
4388 # $QEMU \
4389 ......
4390 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \
4391 -machine ...,memory-encryption=sev0
4392 .....
4394 @end example
4395 @end table
4397 ETEXI
4400 HXCOMM This is the last statement. Insert new options before this line!
4401 STEXI
4402 @end table
4403 ETEXI