doc: switch to modern syntax for VNC TLS setup
[qemu/ericb.git] / qemu-options.hx
blob5515dfaba5526eba0d64523737d49bfb1cb4c9e2
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 " memory-encryption=@var{} memory encryption object to use (default=none)\n",
47 QEMU_ARCH_ALL)
48 STEXI
49 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
50 @findex -machine
51 Select the emulated machine by @var{name}. Use @code{-machine help} to list
52 available machines.
54 For architectures which aim to support live migration compatibility
55 across releases, each release will introduce a new versioned machine
56 type. For example, the 2.8.0 release introduced machine types
57 ``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures.
59 To allow live migration of guests from QEMU version 2.8.0, to QEMU
60 version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8''
61 and ``pc-q35-2.8'' machines too. To allow users live migrating VMs
62 to skip multiple intermediate releases when upgrading, new releases
63 of QEMU will support machine types from many previous versions.
65 Supported machine properties are:
66 @table @option
67 @item accel=@var{accels1}[:@var{accels2}[:...]]
68 This is used to enable an accelerator. Depending on the target architecture,
69 kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is
70 more than one accelerator specified, the next one is used if the previous one
71 fails to initialize.
72 @item kernel_irqchip=on|off
73 Controls in-kernel irqchip support for the chosen accelerator when available.
74 @item gfx_passthru=on|off
75 Enables IGD GFX passthrough support for the chosen machine when available.
76 @item vmport=on|off|auto
77 Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the
78 value based on accel. For accel=xen the default is off otherwise the default
79 is on.
80 @item kvm_shadow_mem=size
81 Defines the size of the KVM shadow MMU.
82 @item dump-guest-core=on|off
83 Include guest memory in a core dump. The default is on.
84 @item mem-merge=on|off
85 Enables or disables memory merge support. This feature, when supported by
86 the host, de-duplicates identical memory pages among VMs instances
87 (enabled by default).
88 @item aes-key-wrap=on|off
89 Enables or disables AES key wrapping support on s390-ccw hosts. This feature
90 controls whether AES wrapping keys will be created to allow
91 execution of AES cryptographic functions. The default is on.
92 @item dea-key-wrap=on|off
93 Enables or disables DEA key wrapping support on s390-ccw hosts. This feature
94 controls whether DEA wrapping keys will be created to allow
95 execution of DEA cryptographic functions. The default is on.
96 @item nvdimm=on|off
97 Enables or disables NVDIMM support. The default is off.
98 @item enforce-config-section=on|off
99 If @option{enforce-config-section} is set to @var{on}, force migration
100 code to send configuration section even if the machine-type sets the
101 @option{migration.send-configuration} property to @var{off}.
102 NOTE: this parameter is deprecated. Please use @option{-global}
103 @option{migration.send-configuration}=@var{on|off} instead.
104 @item memory-encryption=@var{}
105 Memory encryption object to use. The default is none.
106 @end table
107 ETEXI
109 HXCOMM Deprecated by -machine
110 DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
112 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
113 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
114 STEXI
115 @item -cpu @var{model}
116 @findex -cpu
117 Select CPU model (@code{-cpu help} for list and additional feature selection)
118 ETEXI
120 DEF("accel", HAS_ARG, QEMU_OPTION_accel,
121 "-accel [accel=]accelerator[,thread=single|multi]\n"
122 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n"
123 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL)
124 STEXI
125 @item -accel @var{name}[,prop=@var{value}[,...]]
126 @findex -accel
127 This is used to enable an accelerator. Depending on the target architecture,
128 kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is
129 more than one accelerator specified, the next one is used if the previous one
130 fails to initialize.
131 @table @option
132 @item thread=single|multi
133 Controls number of TCG threads. When the TCG is multi-threaded there will be one
134 thread per vCPU therefor taking advantage of additional host cores. The default
135 is to enable multi-threading where both the back-end and front-ends support it and
136 no incompatible TCG features have been enabled (e.g. icount/replay).
137 @end table
138 ETEXI
140 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
141 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
142 " set the number of CPUs to 'n' [default=1]\n"
143 " maxcpus= maximum number of total cpus, including\n"
144 " offline CPUs for hotplug, etc\n"
145 " cores= number of CPU cores on one socket\n"
146 " threads= number of threads on one CPU core\n"
147 " sockets= number of discrete sockets in the system\n",
148 QEMU_ARCH_ALL)
149 STEXI
150 @item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
151 @findex -smp
152 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
153 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
154 to 4.
155 For the PC target, the number of @var{cores} per socket, the number
156 of @var{threads} per cores and the total number of @var{sockets} can be
157 specified. Missing values will be computed. If any on the three values is
158 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
159 specifies the maximum number of hotpluggable CPUs.
160 ETEXI
162 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
163 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
164 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
165 "-numa dist,src=source,dst=destination,val=distance\n"
166 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n",
167 QEMU_ARCH_ALL)
168 STEXI
169 @item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
170 @itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
171 @itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance}
172 @itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}]
173 @findex -numa
174 Define a NUMA node and assign RAM and VCPUs to it.
175 Set the NUMA distance from a source node to a destination node.
177 Legacy VCPU assignment uses @samp{cpus} option where
178 @var{firstcpu} and @var{lastcpu} are CPU indexes. Each
179 @samp{cpus} option represent a contiguous range of CPU indexes
180 (or a single VCPU if @var{lastcpu} is omitted). A non-contiguous
181 set of VCPUs can be represented by providing multiple @samp{cpus}
182 options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically
183 split between them.
185 For example, the following option assigns VCPUs 0, 1, 2 and 5 to
186 a NUMA node:
187 @example
188 -numa node,cpus=0-2,cpus=5
189 @end example
191 @samp{cpu} option is a new alternative to @samp{cpus} option
192 which uses @samp{socket-id|core-id|thread-id} properties to assign
193 CPU objects to a @var{node} using topology layout properties of CPU.
194 The set of properties is machine specific, and depends on used
195 machine type/@samp{smp} options. It could be queried with
196 @samp{hotpluggable-cpus} monitor command.
197 @samp{node-id} property specifies @var{node} to which CPU object
198 will be assigned, it's required for @var{node} to be declared
199 with @samp{node} option before it's used with @samp{cpu} option.
201 For example:
202 @example
203 -M pc \
204 -smp 1,sockets=2,maxcpus=2 \
205 -numa node,nodeid=0 -numa node,nodeid=1 \
206 -numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1
207 @end example
209 @samp{mem} assigns a given RAM amount to a node. @samp{memdev}
210 assigns RAM from a given memory backend device to a node. If
211 @samp{mem} and @samp{memdev} are omitted in all nodes, RAM is
212 split equally between them.
214 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore,
215 if one node uses @samp{memdev}, all of them have to use it.
217 @var{source} and @var{destination} are NUMA node IDs.
218 @var{distance} is the NUMA distance from @var{source} to @var{destination}.
219 The distance from a node to itself is always 10. If any pair of nodes is
220 given a distance, then all pairs must be given distances. Although, when
221 distances are only given in one direction for each pair of nodes, then
222 the distances in the opposite directions are assumed to be the same. If,
223 however, an asymmetrical pair of distances is given for even one node
224 pair, then all node pairs must be provided distance values for both
225 directions, even when they are symmetrical. When a node is unreachable
226 from another node, set the pair's distance to 255.
228 Note that the -@option{numa} option doesn't allocate any of the
229 specified resources, it just assigns existing resources to NUMA
230 nodes. This means that one still has to use the @option{-m},
231 @option{-smp} options to allocate RAM and VCPUs respectively.
233 ETEXI
235 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
236 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
237 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
238 STEXI
239 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
240 @findex -add-fd
242 Add a file descriptor to an fd set. Valid options are:
244 @table @option
245 @item fd=@var{fd}
246 This option defines the file descriptor of which a duplicate is added to fd set.
247 The file descriptor cannot be stdin, stdout, or stderr.
248 @item set=@var{set}
249 This option defines the ID of the fd set to add the file descriptor to.
250 @item opaque=@var{opaque}
251 This option defines a free-form string that can be used to describe @var{fd}.
252 @end table
254 You can open an image using pre-opened file descriptors from an fd set:
255 @example
256 qemu-system-i386
257 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
258 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
259 -drive file=/dev/fdset/2,index=0,media=disk
260 @end example
261 ETEXI
263 DEF("set", HAS_ARG, QEMU_OPTION_set,
264 "-set group.id.arg=value\n"
265 " set <arg> parameter for item <id> of type <group>\n"
266 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
267 STEXI
268 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
269 @findex -set
270 Set parameter @var{arg} for item @var{id} of type @var{group}
271 ETEXI
273 DEF("global", HAS_ARG, QEMU_OPTION_global,
274 "-global driver.property=value\n"
275 "-global driver=driver,property=property,value=value\n"
276 " set a global default for a driver property\n",
277 QEMU_ARCH_ALL)
278 STEXI
279 @item -global @var{driver}.@var{prop}=@var{value}
280 @itemx -global driver=@var{driver},property=@var{property},value=@var{value}
281 @findex -global
282 Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
284 @example
285 qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img
286 @end example
288 In particular, you can use this to set driver properties for devices which are
289 created automatically by the machine model. To create a device which is not
290 created automatically and set properties on it, use -@option{device}.
292 -global @var{driver}.@var{prop}=@var{value} is shorthand for -global
293 driver=@var{driver},property=@var{prop},value=@var{value}. The
294 longhand syntax works even when @var{driver} contains a dot.
295 ETEXI
297 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
298 "-boot [order=drives][,once=drives][,menu=on|off]\n"
299 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
300 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
301 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
302 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
303 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
304 QEMU_ARCH_ALL)
305 STEXI
306 @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]
307 @findex -boot
308 Specify boot order @var{drives} as a string of drive letters. Valid
309 drive letters depend on the target architecture. The x86 PC uses: a, b
310 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
311 from network adapter 1-4), hard disk boot is the default. To apply a
312 particular boot order only on the first startup, specify it via
313 @option{once}. Note that the @option{order} or @option{once} parameter
314 should not be used together with the @option{bootindex} property of
315 devices, since the firmware implementations normally do not support both
316 at the same time.
318 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
319 as firmware/BIOS supports them. The default is non-interactive boot.
321 A splash picture could be passed to bios, enabling user to show it as logo,
322 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
323 supports them. Currently Seabios for X86 system support it.
324 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
325 format(true color). The resolution should be supported by the SVGA mode, so
326 the recommended is 320x240, 640x480, 800x640.
328 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
329 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
330 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
331 system support it.
333 Do strict boot via @option{strict=on} as far as firmware/BIOS
334 supports it. This only effects when boot priority is changed by
335 bootindex options. The default is non-strict boot.
337 @example
338 # try to boot from network first, then from hard disk
339 qemu-system-i386 -boot order=nc
340 # boot from CD-ROM first, switch back to default order after reboot
341 qemu-system-i386 -boot once=d
342 # boot with a splash picture for 5 seconds.
343 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
344 @end example
346 Note: The legacy format '-boot @var{drives}' is still supported but its
347 use is discouraged as it may be removed from future versions.
348 ETEXI
350 DEF("m", HAS_ARG, QEMU_OPTION_m,
351 "-m [size=]megs[,slots=n,maxmem=size]\n"
352 " configure guest RAM\n"
353 " size: initial amount of guest memory\n"
354 " slots: number of hotplug slots (default: none)\n"
355 " maxmem: maximum amount of guest memory (default: none)\n"
356 "NOTE: Some architectures might enforce a specific granularity\n",
357 QEMU_ARCH_ALL)
358 STEXI
359 @item -m [size=]@var{megs}[,slots=n,maxmem=size]
360 @findex -m
361 Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
362 Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
363 megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
364 could be used to set amount of hotpluggable memory slots and maximum amount of
365 memory. Note that @var{maxmem} must be aligned to the page size.
367 For example, the following command-line sets the guest startup RAM size to
368 1GB, creates 3 slots to hotplug additional memory and sets the maximum
369 memory the guest can reach to 4GB:
371 @example
372 qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
373 @end example
375 If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
376 be enabled and the guest startup RAM will never increase.
377 ETEXI
379 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
380 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
381 STEXI
382 @item -mem-path @var{path}
383 @findex -mem-path
384 Allocate guest RAM from a temporarily created file in @var{path}.
385 ETEXI
387 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
388 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
389 QEMU_ARCH_ALL)
390 STEXI
391 @item -mem-prealloc
392 @findex -mem-prealloc
393 Preallocate memory when using -mem-path.
394 ETEXI
396 DEF("k", HAS_ARG, QEMU_OPTION_k,
397 "-k language use keyboard layout (for example 'fr' for French)\n",
398 QEMU_ARCH_ALL)
399 STEXI
400 @item -k @var{language}
401 @findex -k
402 Use keyboard layout @var{language} (for example @code{fr} for
403 French). This option is only needed where it is not easy to get raw PC
404 keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
405 display). You don't normally need to use it on PC/Linux or PC/Windows
406 hosts.
408 The available layouts are:
409 @example
410 ar de-ch es fo fr-ca hu ja mk no pt-br sv
411 da en-gb et fr fr-ch is lt nl pl ru th
412 de en-us fi fr-be hr it lv nl-be pt sl tr
413 @end example
415 The default is @code{en-us}.
416 ETEXI
419 DEF("audio-help", 0, QEMU_OPTION_audio_help,
420 "-audio-help print list of audio drivers and their options\n",
421 QEMU_ARCH_ALL)
422 STEXI
423 @item -audio-help
424 @findex -audio-help
425 Will show the audio subsystem help: list of drivers, tunable
426 parameters.
427 ETEXI
429 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
430 "-soundhw c1,... enable audio support\n"
431 " and only specified sound cards (comma separated list)\n"
432 " use '-soundhw help' to get the list of supported cards\n"
433 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
434 STEXI
435 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
436 @findex -soundhw
437 Enable audio and selected sound hardware. Use 'help' to print all
438 available sound hardware.
440 @example
441 qemu-system-i386 -soundhw sb16,adlib disk.img
442 qemu-system-i386 -soundhw es1370 disk.img
443 qemu-system-i386 -soundhw ac97 disk.img
444 qemu-system-i386 -soundhw hda disk.img
445 qemu-system-i386 -soundhw all disk.img
446 qemu-system-i386 -soundhw help
447 @end example
449 Note that Linux's i810_audio OSS kernel (for AC97) module might
450 require manually specifying clocking.
452 @example
453 modprobe i810_audio clocking=48000
454 @end example
455 ETEXI
457 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
458 "-balloon virtio[,addr=str]\n"
459 " enable virtio balloon device (deprecated)\n", QEMU_ARCH_ALL)
460 STEXI
461 @item -balloon virtio[,addr=@var{addr}]
462 @findex -balloon
463 Enable virtio balloon device, optionally with PCI address @var{addr}. This
464 option is deprecated, use @option{-device virtio-balloon} instead.
465 ETEXI
467 DEF("device", HAS_ARG, QEMU_OPTION_device,
468 "-device driver[,prop[=value][,...]]\n"
469 " add device (based on driver)\n"
470 " prop=value,... sets driver properties\n"
471 " use '-device help' to print all possible drivers\n"
472 " use '-device driver,help' to print all possible properties\n",
473 QEMU_ARCH_ALL)
474 STEXI
475 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
476 @findex -device
477 Add device @var{driver}. @var{prop}=@var{value} sets driver
478 properties. Valid properties depend on the driver. To get help on
479 possible drivers and properties, use @code{-device help} and
480 @code{-device @var{driver},help}.
482 Some drivers are:
483 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}]
485 Add an IPMI BMC. This is a simulation of a hardware management
486 interface processor that normally sits on a system. It provides
487 a watchdog and the ability to reset and power control the system.
488 You need to connect this to an IPMI interface to make it useful
490 The IPMI slave address to use for the BMC. The default is 0x20.
491 This address is the BMC's address on the I2C network of management
492 controllers. If you don't know what this means, it is safe to ignore
495 @table @option
496 @item bmc=@var{id}
497 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
498 @item slave_addr=@var{val}
499 Define slave address to use for the BMC. The default is 0x20.
500 @item sdrfile=@var{file}
501 file containing raw Sensor Data Records (SDR) data. The default is none.
502 @item fruareasize=@var{val}
503 size of a Field Replaceable Unit (FRU) area. The default is 1024.
504 @item frudatafile=@var{file}
505 file containing raw Field Replaceable Unit (FRU) inventory data. The default is none.
506 @end table
508 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
510 Add a connection to an external IPMI BMC simulator. Instead of
511 locally emulating the BMC like the above item, instead connect
512 to an external entity that provides the IPMI services.
514 A connection is made to an external BMC simulator. If you do this, it
515 is strongly recommended that you use the "reconnect=" chardev option
516 to reconnect to the simulator if the connection is lost. Note that if
517 this is not used carefully, it can be a security issue, as the
518 interface has the ability to send resets, NMIs, and power off the VM.
519 It's best if QEMU makes a connection to an external simulator running
520 on a secure port on localhost, so neither the simulator nor QEMU is
521 exposed to any outside network.
523 See the "lanserv/README.vm" file in the OpenIPMI library for more
524 details on the external interface.
526 @item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
528 Add a KCS IPMI interafce on the ISA bus. This also adds a
529 corresponding ACPI and SMBIOS entries, if appropriate.
531 @table @option
532 @item bmc=@var{id}
533 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
534 @item ioport=@var{val}
535 Define the I/O address of the interface. The default is 0xca0 for KCS.
536 @item irq=@var{val}
537 Define the interrupt to use. The default is 5. To disable interrupts,
538 set this to 0.
539 @end table
541 @item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
543 Like the KCS interface, but defines a BT interface. The default port is
544 0xe4 and the default interrupt is 5.
546 ETEXI
548 DEF("name", HAS_ARG, QEMU_OPTION_name,
549 "-name string1[,process=string2][,debug-threads=on|off]\n"
550 " set the name of the guest\n"
551 " string1 sets the window title and string2 the process name (on Linux)\n"
552 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
553 " NOTE: The thread names are for debugging and not a stable API.\n",
554 QEMU_ARCH_ALL)
555 STEXI
556 @item -name @var{name}
557 @findex -name
558 Sets the @var{name} of the guest.
559 This name will be displayed in the SDL window caption.
560 The @var{name} will also be used for the VNC server.
561 Also optionally set the top visible process name in Linux.
562 Naming of individual threads can also be enabled on Linux to aid debugging.
563 ETEXI
565 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
566 "-uuid %08x-%04x-%04x-%04x-%012x\n"
567 " specify machine UUID\n", QEMU_ARCH_ALL)
568 STEXI
569 @item -uuid @var{uuid}
570 @findex -uuid
571 Set system UUID.
572 ETEXI
574 STEXI
575 @end table
576 ETEXI
577 DEFHEADING()
579 DEFHEADING(Block device options:)
580 STEXI
581 @table @option
582 ETEXI
584 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
585 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
586 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
587 STEXI
588 @item -fda @var{file}
589 @itemx -fdb @var{file}
590 @findex -fda
591 @findex -fdb
592 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
593 ETEXI
595 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
596 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
597 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
598 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
599 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
600 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
601 STEXI
602 @item -hda @var{file}
603 @itemx -hdb @var{file}
604 @itemx -hdc @var{file}
605 @itemx -hdd @var{file}
606 @findex -hda
607 @findex -hdb
608 @findex -hdc
609 @findex -hdd
610 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
611 ETEXI
613 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
614 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
615 QEMU_ARCH_ALL)
616 STEXI
617 @item -cdrom @var{file}
618 @findex -cdrom
619 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
620 @option{-cdrom} at the same time). You can use the host CD-ROM by
621 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
622 ETEXI
624 DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev,
625 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n"
626 " [,cache.direct=on|off][,cache.no-flush=on|off]\n"
627 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n"
628 " [,driver specific parameters...]\n"
629 " configure a block backend\n", QEMU_ARCH_ALL)
630 STEXI
631 @item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]]
632 @findex -blockdev
634 Define a new block driver node. Some of the options apply to all block drivers,
635 other options are only accepted for a specific block driver. See below for a
636 list of generic options and options for the most common block drivers.
638 Options that expect a reference to another node (e.g. @code{file}) can be
639 given in two ways. Either you specify the node name of an already existing node
640 (file=@var{node-name}), or you define a new node inline, adding options
641 for the referenced node after a dot (file.filename=@var{path},file.aio=native).
643 A block driver node created with @option{-blockdev} can be used for a guest
644 device by specifying its node name for the @code{drive} property in a
645 @option{-device} argument that defines a block device.
647 @table @option
648 @item Valid options for any block driver node:
650 @table @code
651 @item driver
652 Specifies the block driver to use for the given node.
653 @item node-name
654 This defines the name of the block driver node by which it will be referenced
655 later. The name must be unique, i.e. it must not match the name of a different
656 block driver node, or (if you use @option{-drive} as well) the ID of a drive.
658 If no node name is specified, it is automatically generated. The generated node
659 name is not intended to be predictable and changes between QEMU invocations.
660 For the top level, an explicit node name must be specified.
661 @item read-only
662 Open the node read-only. Guest write attempts will fail.
663 @item cache.direct
664 The host page cache can be avoided with @option{cache.direct=on}. This will
665 attempt to do disk IO directly to the guest's memory. QEMU may still perform an
666 internal copy of the data.
667 @item cache.no-flush
668 In case you don't care about data integrity over host failures, you can use
669 @option{cache.no-flush=on}. This option tells QEMU that it never needs to write
670 any data to the disk but can instead keep things in cache. If anything goes
671 wrong, like your host losing power, the disk storage getting disconnected
672 accidentally, etc. your image will most probably be rendered unusable.
673 @item discard=@var{discard}
674 @var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls
675 whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are
676 ignored or passed to the filesystem. Some machine types may not support
677 discard requests.
678 @item detect-zeroes=@var{detect-zeroes}
679 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
680 conversion of plain zero writes by the OS to driver specific optimized
681 zero write commands. You may even choose "unmap" if @var{discard} is set
682 to "unmap" to allow a zero write to be converted to an @code{unmap} operation.
683 @end table
685 @item Driver-specific options for @code{file}
687 This is the protocol-level block driver for accessing regular files.
689 @table @code
690 @item filename
691 The path to the image file in the local filesystem
692 @item aio
693 Specifies the AIO backend (threads/native, default: threads)
694 @item locking
695 Specifies whether the image file is protected with Linux OFD / POSIX locks. The
696 default is to use the Linux Open File Descriptor API if available, otherwise no
697 lock is applied. (auto/on/off, default: auto)
698 @end table
699 Example:
700 @example
701 -blockdev driver=file,node-name=disk,filename=disk.img
702 @end example
704 @item Driver-specific options for @code{raw}
706 This is the image format block driver for raw images. It is usually
707 stacked on top of a protocol level block driver such as @code{file}.
709 @table @code
710 @item file
711 Reference to or definition of the data source block driver node
712 (e.g. a @code{file} driver node)
713 @end table
714 Example 1:
715 @example
716 -blockdev driver=file,node-name=disk_file,filename=disk.img
717 -blockdev driver=raw,node-name=disk,file=disk_file
718 @end example
719 Example 2:
720 @example
721 -blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img
722 @end example
724 @item Driver-specific options for @code{qcow2}
726 This is the image format block driver for qcow2 images. It is usually
727 stacked on top of a protocol level block driver such as @code{file}.
729 @table @code
730 @item file
731 Reference to or definition of the data source block driver node
732 (e.g. a @code{file} driver node)
734 @item backing
735 Reference to or definition of the backing file block device (default is taken
736 from the image file). It is allowed to pass @code{null} here in order to disable
737 the default backing file.
739 @item lazy-refcounts
740 Whether to enable the lazy refcounts feature (on/off; default is taken from the
741 image file)
743 @item cache-size
744 The maximum total size of the L2 table and refcount block caches in bytes
745 (default: 1048576 bytes or 8 clusters, whichever is larger)
747 @item l2-cache-size
748 The maximum size of the L2 table cache in bytes
749 (default: 4/5 of the total cache size)
751 @item refcount-cache-size
752 The maximum size of the refcount block cache in bytes
753 (default: 1/5 of the total cache size)
755 @item cache-clean-interval
756 Clean unused entries in the L2 and refcount caches. The interval is in seconds.
757 The default value is 0 and it disables this feature.
759 @item pass-discard-request
760 Whether discard requests to the qcow2 device should be forwarded to the data
761 source (on/off; default: on if discard=unmap is specified, off otherwise)
763 @item pass-discard-snapshot
764 Whether discard requests for the data source should be issued when a snapshot
765 operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off;
766 default: on)
768 @item pass-discard-other
769 Whether discard requests for the data source should be issued on other
770 occasions where a cluster gets freed (on/off; default: off)
772 @item overlap-check
773 Which overlap checks to perform for writes to the image
774 (none/constant/cached/all; default: cached). For details or finer
775 granularity control refer to the QAPI documentation of @code{blockdev-add}.
776 @end table
778 Example 1:
779 @example
780 -blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
781 -blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216
782 @end example
783 Example 2:
784 @example
785 -blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2
786 @end example
788 @item Driver-specific options for other drivers
789 Please refer to the QAPI documentation of the @code{blockdev-add} QMP command.
791 @end table
793 ETEXI
795 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
796 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
797 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
798 " [,snapshot=on|off][,rerror=ignore|stop|report]\n"
799 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
800 " [,readonly=on|off][,copy-on-read=on|off]\n"
801 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
802 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
803 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
804 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
805 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
806 " [[,iops_size=is]]\n"
807 " [[,group=g]]\n"
808 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
809 STEXI
810 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
811 @findex -drive
813 Define a new drive. This includes creating a block driver node (the backend) as
814 well as a guest device, and is mostly a shortcut for defining the corresponding
815 @option{-blockdev} and @option{-device} options.
817 @option{-drive} accepts all options that are accepted by @option{-blockdev}. In
818 addition, it knows the following options:
820 @table @option
821 @item file=@var{file}
822 This option defines which disk image (@pxref{disk_images}) to use with
823 this drive. If the filename contains comma, you must double it
824 (for instance, "file=my,,file" to use file "my,file").
826 Special files such as iSCSI devices can be specified using protocol
827 specific URLs. See the section for "Device URL Syntax" for more information.
828 @item if=@var{interface}
829 This option defines on which type on interface the drive is connected.
830 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
831 @item bus=@var{bus},unit=@var{unit}
832 These options define where is connected the drive by defining the bus number and
833 the unit id.
834 @item index=@var{index}
835 This option defines where is connected the drive by using an index in the list
836 of available connectors of a given interface type.
837 @item media=@var{media}
838 This option defines the type of the media: disk or cdrom.
839 @item snapshot=@var{snapshot}
840 @var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
841 (see @option{-snapshot}).
842 @item cache=@var{cache}
843 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough"
844 and controls how the host cache is used to access block data. This is a
845 shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
846 options (as in @option{-blockdev}), and additionally @option{cache.writeback},
847 which provides a default for the @option{write-cache} option of block guest
848 devices (as in @option{-device}). The modes correspond to the following
849 settings:
851 @c Our texi2pod.pl script doesn't support @multitable, so fall back to using
852 @c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
853 @c and the HTML output.
854 @example
855 @ │ cache.writeback cache.direct cache.no-flush
856 ─────────────┼─────────────────────────────────────────────────
857 writeback │ on off off
858 none │ on on off
859 writethrough │ off off off
860 directsync │ off on off
861 unsafe │ on off on
862 @end example
864 The default mode is @option{cache=writeback}.
866 @item aio=@var{aio}
867 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
868 @item format=@var{format}
869 Specify which disk @var{format} will be used rather than detecting
870 the format. Can be used to specify format=raw to avoid interpreting
871 an untrusted format header.
872 @item werror=@var{action},rerror=@var{action}
873 Specify which @var{action} to take on write and read errors. Valid actions are:
874 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
875 "report" (report the error to the guest), "enospc" (pause QEMU only if the
876 host disk is full; report the error to the guest otherwise).
877 The default setting is @option{werror=enospc} and @option{rerror=report}.
878 @item copy-on-read=@var{copy-on-read}
879 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
880 file sectors into the image file.
881 @item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
882 Specify bandwidth throttling limits in bytes per second, either for all request
883 types or for reads or writes only. Small values can lead to timeouts or hangs
884 inside the guest. A safe minimum for disks is 2 MB/s.
885 @item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
886 Specify bursts in bytes per second, either for all request types or for reads
887 or writes only. Bursts allow the guest I/O to spike above the limit
888 temporarily.
889 @item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
890 Specify request rate limits in requests per second, either for all request
891 types or for reads or writes only.
892 @item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
893 Specify bursts in requests per second, either for all request types or for reads
894 or writes only. Bursts allow the guest I/O to spike above the limit
895 temporarily.
896 @item iops_size=@var{is}
897 Let every @var{is} bytes of a request count as a new request for iops
898 throttling purposes. Use this option to prevent guests from circumventing iops
899 limits by sending fewer but larger requests.
900 @item group=@var{g}
901 Join a throttling quota group with given name @var{g}. All drives that are
902 members of the same group are accounted for together. Use this option to
903 prevent guests from circumventing throttling limits by using many small disks
904 instead of a single larger disk.
905 @end table
907 By default, the @option{cache.writeback=on} mode is used. It will report data
908 writes as completed as soon as the data is present in the host page cache.
909 This is safe as long as your guest OS makes sure to correctly flush disk caches
910 where needed. If your guest OS does not handle volatile disk write caches
911 correctly and your host crashes or loses power, then the guest may experience
912 data corruption.
914 For such guests, you should consider using @option{cache.writeback=off}. This
915 means that the host page cache will be used to read and write data, but write
916 notification will be sent to the guest only after QEMU has made sure to flush
917 each write to the disk. Be aware that this has a major impact on performance.
919 When using the @option{-snapshot} option, unsafe caching is always used.
921 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
922 useful when the backing file is over a slow network. By default copy-on-read
923 is off.
925 Instead of @option{-cdrom} you can use:
926 @example
927 qemu-system-i386 -drive file=file,index=2,media=cdrom
928 @end example
930 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
931 use:
932 @example
933 qemu-system-i386 -drive file=file,index=0,media=disk
934 qemu-system-i386 -drive file=file,index=1,media=disk
935 qemu-system-i386 -drive file=file,index=2,media=disk
936 qemu-system-i386 -drive file=file,index=3,media=disk
937 @end example
939 You can open an image using pre-opened file descriptors from an fd set:
940 @example
941 qemu-system-i386
942 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
943 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
944 -drive file=/dev/fdset/2,index=0,media=disk
945 @end example
947 You can connect a CDROM to the slave of ide0:
948 @example
949 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
950 @end example
952 If you don't specify the "file=" argument, you define an empty drive:
953 @example
954 qemu-system-i386 -drive if=ide,index=1,media=cdrom
955 @end example
957 Instead of @option{-fda}, @option{-fdb}, you can use:
958 @example
959 qemu-system-i386 -drive file=file,index=0,if=floppy
960 qemu-system-i386 -drive file=file,index=1,if=floppy
961 @end example
963 By default, @var{interface} is "ide" and @var{index} is automatically
964 incremented:
965 @example
966 qemu-system-i386 -drive file=a -drive file=b"
967 @end example
968 is interpreted like:
969 @example
970 qemu-system-i386 -hda a -hdb b
971 @end example
972 ETEXI
974 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
975 "-mtdblock file use 'file' as on-board Flash memory image\n",
976 QEMU_ARCH_ALL)
977 STEXI
978 @item -mtdblock @var{file}
979 @findex -mtdblock
980 Use @var{file} as on-board Flash memory image.
981 ETEXI
983 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
984 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
985 STEXI
986 @item -sd @var{file}
987 @findex -sd
988 Use @var{file} as SecureDigital card image.
989 ETEXI
991 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
992 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
993 STEXI
994 @item -pflash @var{file}
995 @findex -pflash
996 Use @var{file} as a parallel flash image.
997 ETEXI
999 DEF("snapshot", 0, QEMU_OPTION_snapshot,
1000 "-snapshot write to temporary files instead of disk image files\n",
1001 QEMU_ARCH_ALL)
1002 STEXI
1003 @item -snapshot
1004 @findex -snapshot
1005 Write to temporary files instead of disk image files. In this case,
1006 the raw disk image you use is not written back. You can however force
1007 the write back by pressing @key{C-a s} (@pxref{disk_images}).
1008 ETEXI
1010 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
1011 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1012 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1013 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1014 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1015 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1016 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1017 " [[,throttling.iops-size=is]]\n",
1018 QEMU_ARCH_ALL)
1020 STEXI
1022 @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}]
1023 @findex -fsdev
1024 Define a new file system device. Valid options are:
1025 @table @option
1026 @item @var{fsdriver}
1027 This option specifies the fs driver backend to use.
1028 Currently "local", "handle" and "proxy" file system drivers are supported.
1029 @item id=@var{id}
1030 Specifies identifier for this device
1031 @item path=@var{path}
1032 Specifies the export path for the file system device. Files under
1033 this path will be available to the 9p client on the guest.
1034 @item security_model=@var{security_model}
1035 Specifies the security model to be used for this export path.
1036 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1037 In "passthrough" security model, files are stored using the same
1038 credentials as they are created on the guest. This requires QEMU
1039 to run as root. In "mapped-xattr" security model, some of the file
1040 attributes like uid, gid, mode bits and link target are stored as
1041 file attributes. For "mapped-file" these attributes are stored in the
1042 hidden .virtfs_metadata directory. Directories exported by this security model cannot
1043 interact with other unix tools. "none" security model is same as
1044 passthrough except the sever won't report failures if it fails to
1045 set file attributes like ownership. Security model is mandatory
1046 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1047 security model as a parameter.
1048 @item writeout=@var{writeout}
1049 This is an optional argument. The only supported value is "immediate".
1050 This means that host page cache will be used to read and write data but
1051 write notification will be sent to the guest only when the data has been
1052 reported as written by the storage subsystem.
1053 @item readonly
1054 Enables exporting 9p share as a readonly mount for guests. By default
1055 read-write access is given.
1056 @item socket=@var{socket}
1057 Enables proxy filesystem driver to use passed socket file for communicating
1058 with virtfs-proxy-helper
1059 @item sock_fd=@var{sock_fd}
1060 Enables proxy filesystem driver to use passed socket descriptor for
1061 communicating with virtfs-proxy-helper. Usually a helper like libvirt
1062 will create socketpair and pass one of the fds as sock_fd
1063 @item fmode=@var{fmode}
1064 Specifies the default mode for newly created files on the host. Works only
1065 with security models "mapped-xattr" and "mapped-file".
1066 @item dmode=@var{dmode}
1067 Specifies the default mode for newly created directories on the host. Works
1068 only with security models "mapped-xattr" and "mapped-file".
1069 @end table
1071 -fsdev option is used along with -device driver "virtio-9p-pci".
1072 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
1073 Options for virtio-9p-pci driver are:
1074 @table @option
1075 @item fsdev=@var{id}
1076 Specifies the id value specified along with -fsdev option
1077 @item mount_tag=@var{mount_tag}
1078 Specifies the tag name to be used by the guest to mount this export point
1079 @end table
1081 ETEXI
1083 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
1084 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1085 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1086 QEMU_ARCH_ALL)
1088 STEXI
1090 @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}]
1091 @findex -virtfs
1093 The general form of a Virtual File system pass-through options are:
1094 @table @option
1095 @item @var{fsdriver}
1096 This option specifies the fs driver backend to use.
1097 Currently "local", "handle" and "proxy" file system drivers are supported.
1098 @item id=@var{id}
1099 Specifies identifier for this device
1100 @item path=@var{path}
1101 Specifies the export path for the file system device. Files under
1102 this path will be available to the 9p client on the guest.
1103 @item security_model=@var{security_model}
1104 Specifies the security model to be used for this export path.
1105 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1106 In "passthrough" security model, files are stored using the same
1107 credentials as they are created on the guest. This requires QEMU
1108 to run as root. In "mapped-xattr" security model, some of the file
1109 attributes like uid, gid, mode bits and link target are stored as
1110 file attributes. For "mapped-file" these attributes are stored in the
1111 hidden .virtfs_metadata directory. Directories exported by this security model cannot
1112 interact with other unix tools. "none" security model is same as
1113 passthrough except the sever won't report failures if it fails to
1114 set file attributes like ownership. Security model is mandatory only
1115 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1116 model as a parameter.
1117 @item writeout=@var{writeout}
1118 This is an optional argument. The only supported value is "immediate".
1119 This means that host page cache will be used to read and write data but
1120 write notification will be sent to the guest only when the data has been
1121 reported as written by the storage subsystem.
1122 @item readonly
1123 Enables exporting 9p share as a readonly mount for guests. By default
1124 read-write access is given.
1125 @item socket=@var{socket}
1126 Enables proxy filesystem driver to use passed socket file for
1127 communicating with virtfs-proxy-helper. Usually a helper like libvirt
1128 will create socketpair and pass one of the fds as sock_fd
1129 @item sock_fd
1130 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
1131 descriptor for interfacing with virtfs-proxy-helper
1132 @item fmode=@var{fmode}
1133 Specifies the default mode for newly created files on the host. Works only
1134 with security models "mapped-xattr" and "mapped-file".
1135 @item dmode=@var{dmode}
1136 Specifies the default mode for newly created directories on the host. Works
1137 only with security models "mapped-xattr" and "mapped-file".
1138 @end table
1139 ETEXI
1141 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
1142 "-virtfs_synth Create synthetic file system image\n",
1143 QEMU_ARCH_ALL)
1144 STEXI
1145 @item -virtfs_synth
1146 @findex -virtfs_synth
1147 Create synthetic file system image
1148 ETEXI
1150 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
1151 "-iscsi [user=user][,password=password]\n"
1152 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1153 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
1154 " [,timeout=timeout]\n"
1155 " iSCSI session parameters\n", QEMU_ARCH_ALL)
1157 STEXI
1158 @item -iscsi
1159 @findex -iscsi
1160 Configure iSCSI session parameters.
1161 ETEXI
1163 STEXI
1164 @end table
1165 ETEXI
1166 DEFHEADING()
1168 DEFHEADING(USB options:)
1169 STEXI
1170 @table @option
1171 ETEXI
1173 DEF("usb", 0, QEMU_OPTION_usb,
1174 "-usb enable the USB driver (if it is not used by default yet)\n",
1175 QEMU_ARCH_ALL)
1176 STEXI
1177 @item -usb
1178 @findex -usb
1179 Enable the USB driver (if it is not used by default yet).
1180 ETEXI
1182 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
1183 "-usbdevice name add the host or guest USB device 'name'\n",
1184 QEMU_ARCH_ALL)
1185 STEXI
1187 @item -usbdevice @var{devname}
1188 @findex -usbdevice
1189 Add the USB device @var{devname}. Note that this option is deprecated,
1190 please use @code{-device usb-...} instead. @xref{usb_devices}.
1192 @table @option
1194 @item mouse
1195 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1197 @item tablet
1198 Pointer device that uses absolute coordinates (like a touchscreen). This
1199 means QEMU is able to report the mouse position without having to grab the
1200 mouse. Also overrides the PS/2 mouse emulation when activated.
1202 @item braille
1203 Braille device. This will use BrlAPI to display the braille output on a real
1204 or fake device.
1206 @end table
1207 ETEXI
1209 STEXI
1210 @end table
1211 ETEXI
1212 DEFHEADING()
1214 DEFHEADING(Display options:)
1215 STEXI
1216 @table @option
1217 ETEXI
1219 DEF("display", HAS_ARG, QEMU_OPTION_display,
1220 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1221 " [,window_close=on|off][,gl=on|core|es|off]\n"
1222 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1223 "-display vnc=<display>[,<optargs>]\n"
1224 "-display curses\n"
1225 "-display none"
1226 " select display type\n"
1227 "The default display is equivalent to\n"
1228 #if defined(CONFIG_GTK)
1229 "\t\"-display gtk\"\n"
1230 #elif defined(CONFIG_SDL)
1231 "\t\"-display sdl\"\n"
1232 #elif defined(CONFIG_COCOA)
1233 "\t\"-display cocoa\"\n"
1234 #elif defined(CONFIG_VNC)
1235 "\t\"-vnc localhost:0,to=99,id=default\"\n"
1236 #else
1237 "\t\"-display none\"\n"
1238 #endif
1239 , QEMU_ARCH_ALL)
1240 STEXI
1241 @item -display @var{type}
1242 @findex -display
1243 Select type of display to use. This option is a replacement for the
1244 old style -sdl/-curses/... options. Valid values for @var{type} are
1245 @table @option
1246 @item sdl
1247 Display video output via SDL (usually in a separate graphics
1248 window; see the SDL documentation for other possibilities).
1249 @item curses
1250 Display video output via curses. For graphics device models which
1251 support a text mode, QEMU can display this output using a
1252 curses/ncurses interface. Nothing is displayed when the graphics
1253 device is in graphical mode or if the graphics device does not support
1254 a text mode. Generally only the VGA device models support text mode.
1255 @item none
1256 Do not display video output. The guest will still see an emulated
1257 graphics card, but its output will not be displayed to the QEMU
1258 user. This option differs from the -nographic option in that it
1259 only affects what is done with video output; -nographic also changes
1260 the destination of the serial and parallel port data.
1261 @item gtk
1262 Display video output in a GTK window. This interface provides drop-down
1263 menus and other UI elements to configure and control the VM during
1264 runtime.
1265 @item vnc
1266 Start a VNC server on display <arg>
1267 @end table
1268 ETEXI
1270 DEF("nographic", 0, QEMU_OPTION_nographic,
1271 "-nographic disable graphical output and redirect serial I/Os to console\n",
1272 QEMU_ARCH_ALL)
1273 STEXI
1274 @item -nographic
1275 @findex -nographic
1276 Normally, if QEMU is compiled with graphical window support, it displays
1277 output such as guest graphics, guest console, and the QEMU monitor in a
1278 window. With this option, you can totally disable graphical output so
1279 that QEMU is a simple command line application. The emulated serial port
1280 is redirected on the console and muxed with the monitor (unless
1281 redirected elsewhere explicitly). Therefore, you can still use QEMU to
1282 debug a Linux kernel with a serial console. Use @key{C-a h} for help on
1283 switching between the console and monitor.
1284 ETEXI
1286 DEF("curses", 0, QEMU_OPTION_curses,
1287 "-curses shorthand for -display curses\n",
1288 QEMU_ARCH_ALL)
1289 STEXI
1290 @item -curses
1291 @findex -curses
1292 Normally, if QEMU is compiled with graphical window support, it displays
1293 output such as guest graphics, guest console, and the QEMU monitor in a
1294 window. With this option, QEMU can display the VGA output when in text
1295 mode using a curses/ncurses interface. Nothing is displayed in graphical
1296 mode.
1297 ETEXI
1299 DEF("no-frame", 0, QEMU_OPTION_no_frame,
1300 "-no-frame open SDL window without a frame and window decorations\n",
1301 QEMU_ARCH_ALL)
1302 STEXI
1303 @item -no-frame
1304 @findex -no-frame
1305 Do not use decorations for SDL windows and start them using the whole
1306 available screen space. This makes the using QEMU in a dedicated desktop
1307 workspace more convenient.
1308 ETEXI
1310 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1311 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1312 QEMU_ARCH_ALL)
1313 STEXI
1314 @item -alt-grab
1315 @findex -alt-grab
1316 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1317 affects the special keys (for fullscreen, monitor-mode switching, etc).
1318 ETEXI
1320 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1321 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1322 QEMU_ARCH_ALL)
1323 STEXI
1324 @item -ctrl-grab
1325 @findex -ctrl-grab
1326 Use Right-Ctrl 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("no-quit", 0, QEMU_OPTION_no_quit,
1331 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
1332 STEXI
1333 @item -no-quit
1334 @findex -no-quit
1335 Disable SDL window close capability.
1336 ETEXI
1338 DEF("sdl", 0, QEMU_OPTION_sdl,
1339 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL)
1340 STEXI
1341 @item -sdl
1342 @findex -sdl
1343 Enable SDL.
1344 ETEXI
1346 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1347 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1348 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1349 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1350 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1351 " [,tls-ciphers=<list>]\n"
1352 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1353 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1354 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1355 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1356 " [,jpeg-wan-compression=[auto|never|always]]\n"
1357 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1358 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1359 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1360 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1361 " [,gl=[on|off]][,rendernode=<file>]\n"
1362 " enable spice\n"
1363 " at least one of {port, tls-port} is mandatory\n",
1364 QEMU_ARCH_ALL)
1365 STEXI
1366 @item -spice @var{option}[,@var{option}[,...]]
1367 @findex -spice
1368 Enable the spice remote desktop protocol. Valid options are
1370 @table @option
1372 @item port=<nr>
1373 Set the TCP port spice is listening on for plaintext channels.
1375 @item addr=<addr>
1376 Set the IP address spice is listening on. Default is any address.
1378 @item ipv4
1379 @itemx ipv6
1380 @itemx unix
1381 Force using the specified IP version.
1383 @item password=<secret>
1384 Set the password you need to authenticate.
1386 @item sasl
1387 Require that the client use SASL to authenticate with the spice.
1388 The exact choice of authentication method used is controlled from the
1389 system / user's SASL configuration file for the 'qemu' service. This
1390 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1391 unprivileged user, an environment variable SASL_CONF_PATH can be used
1392 to make it search alternate locations for the service config.
1393 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1394 it is recommended that SASL always be combined with the 'tls' and
1395 'x509' settings to enable use of SSL and server certificates. This
1396 ensures a data encryption preventing compromise of authentication
1397 credentials.
1399 @item disable-ticketing
1400 Allow client connects without authentication.
1402 @item disable-copy-paste
1403 Disable copy paste between the client and the guest.
1405 @item disable-agent-file-xfer
1406 Disable spice-vdagent based file-xfer between the client and the guest.
1408 @item tls-port=<nr>
1409 Set the TCP port spice is listening on for encrypted channels.
1411 @item x509-dir=<dir>
1412 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1414 @item x509-key-file=<file>
1415 @itemx x509-key-password=<file>
1416 @itemx x509-cert-file=<file>
1417 @itemx x509-cacert-file=<file>
1418 @itemx x509-dh-key-file=<file>
1419 The x509 file names can also be configured individually.
1421 @item tls-ciphers=<list>
1422 Specify which ciphers to use.
1424 @item tls-channel=[main|display|cursor|inputs|record|playback]
1425 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1426 Force specific channel to be used with or without TLS encryption. The
1427 options can be specified multiple times to configure multiple
1428 channels. The special name "default" can be used to set the default
1429 mode. For channels which are not explicitly forced into one mode the
1430 spice client is allowed to pick tls/plaintext as he pleases.
1432 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1433 Configure image compression (lossless).
1434 Default is auto_glz.
1436 @item jpeg-wan-compression=[auto|never|always]
1437 @itemx zlib-glz-wan-compression=[auto|never|always]
1438 Configure wan image compression (lossy for slow links).
1439 Default is auto.
1441 @item streaming-video=[off|all|filter]
1442 Configure video stream detection. Default is off.
1444 @item agent-mouse=[on|off]
1445 Enable/disable passing mouse events via vdagent. Default is on.
1447 @item playback-compression=[on|off]
1448 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1450 @item seamless-migration=[on|off]
1451 Enable/disable spice seamless migration. Default is off.
1453 @item gl=[on|off]
1454 Enable/disable OpenGL context. Default is off.
1456 @item rendernode=<file>
1457 DRM render node for OpenGL rendering. If not specified, it will pick
1458 the first available. (Since 2.9)
1460 @end table
1461 ETEXI
1463 DEF("portrait", 0, QEMU_OPTION_portrait,
1464 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1465 QEMU_ARCH_ALL)
1466 STEXI
1467 @item -portrait
1468 @findex -portrait
1469 Rotate graphical output 90 deg left (only PXA LCD).
1470 ETEXI
1472 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1473 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1474 QEMU_ARCH_ALL)
1475 STEXI
1476 @item -rotate @var{deg}
1477 @findex -rotate
1478 Rotate graphical output some deg left (only PXA LCD).
1479 ETEXI
1481 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1482 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1483 " select video card type\n", QEMU_ARCH_ALL)
1484 STEXI
1485 @item -vga @var{type}
1486 @findex -vga
1487 Select type of VGA card to emulate. Valid values for @var{type} are
1488 @table @option
1489 @item cirrus
1490 Cirrus Logic GD5446 Video card. All Windows versions starting from
1491 Windows 95 should recognize and use this graphic card. For optimal
1492 performances, use 16 bit color depth in the guest and the host OS.
1493 (This card was the default before QEMU 2.2)
1494 @item std
1495 Standard VGA card with Bochs VBE extensions. If your guest OS
1496 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1497 to use high resolution modes (>= 1280x1024x16) then you should use
1498 this option. (This card is the default since QEMU 2.2)
1499 @item vmware
1500 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1501 recent XFree86/XOrg server or Windows guest with a driver for this
1502 card.
1503 @item qxl
1504 QXL paravirtual graphic card. It is VGA compatible (including VESA
1505 2.0 VBE support). Works best with qxl guest drivers installed though.
1506 Recommended choice when using the spice protocol.
1507 @item tcx
1508 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1509 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1510 fixed resolution of 1024x768.
1511 @item cg3
1512 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1513 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1514 resolutions aimed at people wishing to run older Solaris versions.
1515 @item virtio
1516 Virtio VGA card.
1517 @item none
1518 Disable VGA card.
1519 @end table
1520 ETEXI
1522 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1523 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1524 STEXI
1525 @item -full-screen
1526 @findex -full-screen
1527 Start in full screen.
1528 ETEXI
1530 DEF("g", 1, QEMU_OPTION_g ,
1531 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1532 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1533 STEXI
1534 @item -g @var{width}x@var{height}[x@var{depth}]
1535 @findex -g
1536 Set the initial graphical resolution and depth (PPC, SPARC only).
1537 ETEXI
1539 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1540 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1541 STEXI
1542 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1543 @findex -vnc
1544 Normally, if QEMU is compiled with graphical window support, it displays
1545 output such as guest graphics, guest console, and the QEMU monitor in a
1546 window. With this option, you can have QEMU listen on VNC display
1547 @var{display} and redirect the VGA display over the VNC session. It is
1548 very useful to enable the usb tablet device when using this option
1549 (option @option{-device usb-tablet}). When using the VNC display, you
1550 must use the @option{-k} parameter to set the keyboard layout if you are
1551 not using en-us. Valid syntax for the @var{display} is
1553 @table @option
1555 @item to=@var{L}
1557 With this option, QEMU will try next available VNC @var{display}s, until the
1558 number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1559 available, e.g. port 5900+@var{display} is already used by another
1560 application. By default, to=0.
1562 @item @var{host}:@var{d}
1564 TCP connections will only be allowed from @var{host} on display @var{d}.
1565 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1566 be omitted in which case the server will accept connections from any host.
1568 @item unix:@var{path}
1570 Connections will be allowed over UNIX domain sockets where @var{path} is the
1571 location of a unix socket to listen for connections on.
1573 @item none
1575 VNC is initialized but not started. The monitor @code{change} command
1576 can be used to later start the VNC server.
1578 @end table
1580 Following the @var{display} value there may be one or more @var{option} flags
1581 separated by commas. Valid options are
1583 @table @option
1585 @item reverse
1587 Connect to a listening VNC client via a ``reverse'' connection. The
1588 client is specified by the @var{display}. For reverse network
1589 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1590 is a TCP port number, not a display number.
1592 @item websocket
1594 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1595 If a bare @var{websocket} option is given, the Websocket port is
1596 5700+@var{display}. An alternative port can be specified with the
1597 syntax @code{websocket}=@var{port}.
1599 If @var{host} is specified connections will only be allowed from this host.
1600 It is possible to control the websocket listen address independently, using
1601 the syntax @code{websocket}=@var{host}:@var{port}.
1603 If no TLS credentials are provided, the websocket connection runs in
1604 unencrypted mode. If TLS credentials are provided, the websocket connection
1605 requires encrypted client connections.
1607 @item password
1609 Require that password based authentication is used for client connections.
1611 The password must be set separately using the @code{set_password} command in
1612 the @ref{pcsys_monitor}. The syntax to change your password is:
1613 @code{set_password <protocol> <password>} where <protocol> could be either
1614 "vnc" or "spice".
1616 If you would like to change <protocol> password expiration, you should use
1617 @code{expire_password <protocol> <expiration-time>} where expiration time could
1618 be one of the following options: now, never, +seconds or UNIX time of
1619 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1620 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1621 date and time).
1623 You can also use keywords "now" or "never" for the expiration time to
1624 allow <protocol> password to expire immediately or never expire.
1626 @item tls-creds=@var{ID}
1628 Provides the ID of a set of TLS credentials to use to secure the
1629 VNC server. They will apply to both the normal VNC server socket
1630 and the websocket socket (if enabled). Setting TLS credentials
1631 will cause the VNC server socket to enable the VeNCrypt auth
1632 mechanism. The credentials should have been previously created
1633 using the @option{-object tls-creds} argument.
1635 The @option{tls-creds} parameter obsoletes the @option{tls},
1636 @option{x509}, and @option{x509verify} options, and as such
1637 it is not permitted to set both new and old type options at
1638 the same time.
1640 @item tls
1642 Require that client use TLS when communicating with the VNC server. This
1643 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1644 attack. It is recommended that this option be combined with either the
1645 @option{x509} or @option{x509verify} options.
1647 This option is now deprecated in favor of using the @option{tls-creds}
1648 argument.
1650 @item x509=@var{/path/to/certificate/dir}
1652 Valid if @option{tls} is specified. Require that x509 credentials are used
1653 for negotiating the TLS session. The server will send its x509 certificate
1654 to the client. It is recommended that a password be set on the VNC server
1655 to provide authentication of the client when this is used. The path following
1656 this option specifies where the x509 certificates are to be loaded from.
1657 See the @ref{vnc_security} section for details on generating certificates.
1659 This option is now deprecated in favour of using the @option{tls-creds}
1660 argument.
1662 @item x509verify=@var{/path/to/certificate/dir}
1664 Valid if @option{tls} is specified. Require that x509 credentials are used
1665 for negotiating the TLS session. The server will send its x509 certificate
1666 to the client, and request that the client send its own x509 certificate.
1667 The server will validate the client's certificate against the CA certificate,
1668 and reject clients when validation fails. If the certificate authority is
1669 trusted, this is a sufficient authentication mechanism. You may still wish
1670 to set a password on the VNC server as a second authentication layer. The
1671 path following this option specifies where the x509 certificates are to
1672 be loaded from. See the @ref{vnc_security} section for details on generating
1673 certificates.
1675 This option is now deprecated in favour of using the @option{tls-creds}
1676 argument.
1678 @item sasl
1680 Require that the client use SASL to authenticate with the VNC server.
1681 The exact choice of authentication method used is controlled from the
1682 system / user's SASL configuration file for the 'qemu' service. This
1683 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1684 unprivileged user, an environment variable SASL_CONF_PATH can be used
1685 to make it search alternate locations for the service config.
1686 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1687 it is recommended that SASL always be combined with the 'tls' and
1688 'x509' settings to enable use of SSL and server certificates. This
1689 ensures a data encryption preventing compromise of authentication
1690 credentials. See the @ref{vnc_security} section for details on using
1691 SASL authentication.
1693 @item acl
1695 Turn on access control lists for checking of the x509 client certificate
1696 and SASL party. For x509 certs, the ACL check is made against the
1697 certificate's distinguished name. This is something that looks like
1698 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1699 made against the username, which depending on the SASL plugin, may
1700 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1701 When the @option{acl} flag is set, the initial access list will be
1702 empty, with a @code{deny} policy. Thus no one will be allowed to
1703 use the VNC server until the ACLs have been loaded. This can be
1704 achieved using the @code{acl} monitor command.
1706 @item lossy
1708 Enable lossy compression methods (gradient, JPEG, ...). If this
1709 option is set, VNC client may receive lossy framebuffer updates
1710 depending on its encoding settings. Enabling this option can save
1711 a lot of bandwidth at the expense of quality.
1713 @item non-adaptive
1715 Disable adaptive encodings. Adaptive encodings are enabled by default.
1716 An adaptive encoding will try to detect frequently updated screen regions,
1717 and send updates in these regions using a lossy encoding (like JPEG).
1718 This can be really helpful to save bandwidth when playing videos. Disabling
1719 adaptive encodings restores the original static behavior of encodings
1720 like Tight.
1722 @item share=[allow-exclusive|force-shared|ignore]
1724 Set display sharing policy. 'allow-exclusive' allows clients to ask
1725 for exclusive access. As suggested by the rfb spec this is
1726 implemented by dropping other connections. Connecting multiple
1727 clients in parallel requires all clients asking for a shared session
1728 (vncviewer: -shared switch). This is the default. 'force-shared'
1729 disables exclusive client access. Useful for shared desktop sessions,
1730 where you don't want someone forgetting specify -shared disconnect
1731 everybody else. 'ignore' completely ignores the shared flag and
1732 allows everybody connect unconditionally. Doesn't conform to the rfb
1733 spec but is traditional QEMU behavior.
1735 @item key-delay-ms
1737 Set keyboard delay, for key down and key up events, in milliseconds.
1738 Default is 10. Keyboards are low-bandwidth devices, so this slowdown
1739 can help the device and guest to keep up and not lose events in case
1740 events are arriving in bulk. Possible causes for the latter are flaky
1741 network connections, or scripts for automated testing.
1743 @end table
1744 ETEXI
1746 STEXI
1747 @end table
1748 ETEXI
1749 ARCHHEADING(, QEMU_ARCH_I386)
1751 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1752 STEXI
1753 @table @option
1754 ETEXI
1756 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1757 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1758 QEMU_ARCH_I386)
1759 STEXI
1760 @item -win2k-hack
1761 @findex -win2k-hack
1762 Use it when installing Windows 2000 to avoid a disk full bug. After
1763 Windows 2000 is installed, you no longer need this option (this option
1764 slows down the IDE transfers).
1765 ETEXI
1767 HXCOMM Deprecated by -rtc
1768 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1770 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1771 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1772 QEMU_ARCH_I386)
1773 STEXI
1774 @item -no-fd-bootchk
1775 @findex -no-fd-bootchk
1776 Disable boot signature checking for floppy disks in BIOS. May
1777 be needed to boot from old floppy disks.
1778 ETEXI
1780 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1781 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1782 STEXI
1783 @item -no-acpi
1784 @findex -no-acpi
1785 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1786 it if your guest OS complains about ACPI problems (PC target machine
1787 only).
1788 ETEXI
1790 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1791 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1792 STEXI
1793 @item -no-hpet
1794 @findex -no-hpet
1795 Disable HPET support.
1796 ETEXI
1798 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1799 "-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"
1800 " ACPI table description\n", QEMU_ARCH_I386)
1801 STEXI
1802 @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}]...]
1803 @findex -acpitable
1804 Add ACPI table with specified header fields and context from specified files.
1805 For file=, take whole ACPI table from the specified files, including all
1806 ACPI headers (possible overridden by other options).
1807 For data=, only data
1808 portion of the table is used, all header information is specified in the
1809 command line.
1810 If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1811 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1812 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1813 spec.
1814 ETEXI
1816 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1817 "-smbios file=binary\n"
1818 " load SMBIOS entry from binary file\n"
1819 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1820 " [,uefi=on|off]\n"
1821 " specify SMBIOS type 0 fields\n"
1822 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1823 " [,uuid=uuid][,sku=str][,family=str]\n"
1824 " specify SMBIOS type 1 fields\n"
1825 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1826 " [,asset=str][,location=str]\n"
1827 " specify SMBIOS type 2 fields\n"
1828 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1829 " [,sku=str]\n"
1830 " specify SMBIOS type 3 fields\n"
1831 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1832 " [,asset=str][,part=str]\n"
1833 " specify SMBIOS type 4 fields\n"
1834 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1835 " [,asset=str][,part=str][,speed=%d]\n"
1836 " specify SMBIOS type 17 fields\n",
1837 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1838 STEXI
1839 @item -smbios file=@var{binary}
1840 @findex -smbios
1841 Load SMBIOS entry from binary file.
1843 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1844 Specify SMBIOS type 0 fields
1846 @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}]
1847 Specify SMBIOS type 1 fields
1849 @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}]
1850 Specify SMBIOS type 2 fields
1852 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1853 Specify SMBIOS type 3 fields
1855 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1856 Specify SMBIOS type 4 fields
1858 @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}]
1859 Specify SMBIOS type 17 fields
1860 ETEXI
1862 STEXI
1863 @end table
1864 ETEXI
1865 DEFHEADING()
1867 DEFHEADING(Network options:)
1868 STEXI
1869 @table @option
1870 ETEXI
1872 HXCOMM Legacy slirp options (now moved to -net user):
1873 #ifdef CONFIG_SLIRP
1874 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1875 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1876 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1877 #ifndef _WIN32
1878 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1879 #endif
1880 #endif
1882 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1883 #ifdef CONFIG_SLIRP
1884 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1885 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1886 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1887 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n"
1888 " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1889 #ifndef _WIN32
1890 "[,smb=dir[,smbserver=addr]]\n"
1891 #endif
1892 " configure a user mode network backend with ID 'str',\n"
1893 " its DHCP server and optional services\n"
1894 #endif
1895 #ifdef _WIN32
1896 "-netdev tap,id=str,ifname=name\n"
1897 " configure a host TAP network backend with ID 'str'\n"
1898 #else
1899 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1900 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1901 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1902 " [,poll-us=n]\n"
1903 " configure a host TAP network backend with ID 'str'\n"
1904 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1905 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1906 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1907 " to deconfigure it\n"
1908 " use '[down]script=no' to disable script execution\n"
1909 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1910 " configure it\n"
1911 " use 'fd=h' to connect to an already opened TAP interface\n"
1912 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1913 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1914 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1915 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1916 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1917 " use vhost=on to enable experimental in kernel accelerator\n"
1918 " (only has effect for virtio guests which use MSIX)\n"
1919 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1920 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1921 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1922 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1923 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n"
1924 " spent on busy polling for vhost net\n"
1925 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1926 " configure a host TAP network backend with ID 'str' that is\n"
1927 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1928 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1929 #endif
1930 #ifdef __linux__
1931 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1932 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1933 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1934 " [,rxcookie=rxcookie][,offset=offset]\n"
1935 " configure a network backend with ID 'str' connected to\n"
1936 " an Ethernet over L2TPv3 pseudowire.\n"
1937 " Linux kernel 3.3+ as well as most routers can talk\n"
1938 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1939 " VM to a router and even VM to Host. It is a nearly-universal\n"
1940 " standard (RFC3391). Note - this implementation uses static\n"
1941 " pre-configured tunnels (same as the Linux kernel).\n"
1942 " use 'src=' to specify source address\n"
1943 " use 'dst=' to specify destination address\n"
1944 " use 'udp=on' to specify udp encapsulation\n"
1945 " use 'srcport=' to specify source udp port\n"
1946 " use 'dstport=' to specify destination udp port\n"
1947 " use 'ipv6=on' to force v6\n"
1948 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1949 " well as a weak security measure\n"
1950 " use 'rxcookie=0x012345678' to specify a rxcookie\n"
1951 " use 'txcookie=0x012345678' to specify a txcookie\n"
1952 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1953 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1954 " use 'pincounter=on' to work around broken counter handling in peer\n"
1955 " use 'offset=X' to add an extra offset between header and data\n"
1956 #endif
1957 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1958 " configure a network backend to connect to another network\n"
1959 " using a socket connection\n"
1960 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1961 " configure a network backend to connect to a multicast maddr and port\n"
1962 " use 'localaddr=addr' to specify the host address to send packets from\n"
1963 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1964 " configure a network backend to connect to another network\n"
1965 " using an UDP tunnel\n"
1966 #ifdef CONFIG_VDE
1967 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1968 " configure a network backend to connect to port 'n' of a vde switch\n"
1969 " running on host and listening for incoming connections on 'socketpath'.\n"
1970 " Use group 'groupname' and mode 'octalmode' to change default\n"
1971 " ownership and permissions for communication port.\n"
1972 #endif
1973 #ifdef CONFIG_NETMAP
1974 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1975 " attach to the existing netmap-enabled network interface 'name', or to a\n"
1976 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1977 " netmap device, defaults to '/dev/netmap')\n"
1978 #endif
1979 #ifdef CONFIG_POSIX
1980 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
1981 " configure a vhost-user network, backed by a chardev 'dev'\n"
1982 #endif
1983 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
1984 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL)
1985 DEF("nic", HAS_ARG, QEMU_OPTION_nic,
1986 "-nic [tap|bridge|"
1987 #ifdef CONFIG_SLIRP
1988 "user|"
1989 #endif
1990 #ifdef __linux__
1991 "l2tpv3|"
1992 #endif
1993 #ifdef CONFIG_VDE
1994 "vde|"
1995 #endif
1996 #ifdef CONFIG_NETMAP
1997 "netmap|"
1998 #endif
1999 #ifdef CONFIG_POSIX
2000 "vhost-user|"
2001 #endif
2002 "socket][,option][,...][mac=macaddr]\n"
2003 " initialize an on-board / default host NIC (using MAC address\n"
2004 " macaddr) and connect it to the given host network backend\n"
2005 "-nic none use it alone to have zero network devices (the default is to\n"
2006 " provided a 'user' network connection)\n",
2007 QEMU_ARCH_ALL)
2008 DEF("net", HAS_ARG, QEMU_OPTION_net,
2009 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2010 " configure or create an on-board (or machine default) NIC and\n"
2011 " connect it to hub 0 (please use -nic unless you need a hub)\n"
2012 "-net ["
2013 #ifdef CONFIG_SLIRP
2014 "user|"
2015 #endif
2016 "tap|"
2017 "bridge|"
2018 #ifdef CONFIG_VDE
2019 "vde|"
2020 #endif
2021 #ifdef CONFIG_NETMAP
2022 "netmap|"
2023 #endif
2024 "socket][,option][,option][,...]\n"
2025 " old way to initialize a host network interface\n"
2026 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2027 STEXI
2028 @item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn]
2029 @findex -nic
2030 This option is a shortcut for configuring both the on-board (default) guest
2031 NIC hardware and the host network backend in one go. The host backend options
2032 are the same as with the corresponding @option{-netdev} options below.
2033 The guest NIC model can be set with @option{model=@var{modelname}}.
2034 Use @option{model=help} to list the available device types.
2035 The hardware MAC address can be set with @option{mac=@var{macaddr}}.
2037 The following two example do exactly the same, to show how @option{-nic} can
2038 be used to shorten the command line length (note that the e1000 is the default
2039 on i386, so the @option{model=e1000} parameter could even be omitted here, too):
2040 @example
2041 qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32
2042 qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32
2043 @end example
2045 @item -nic none
2046 Indicate that no network devices should be configured. It is used to override
2047 the default configuration (default NIC with ``user'' host network backend)
2048 which is activated if no other networking options are provided.
2050 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2051 @findex -netdev
2052 Configure user mode host network backend which requires no administrator
2053 privilege to run. Valid options are:
2055 @table @option
2056 @item id=@var{id}
2057 Assign symbolic name for use in monitor commands.
2059 @item ipv4=on|off and ipv6=on|off
2060 Specify that either IPv4 or IPv6 must be enabled. If neither is specified
2061 both protocols are enabled.
2063 @item net=@var{addr}[/@var{mask}]
2064 Set IP network address the guest will see. Optionally specify the netmask,
2065 either in the form a.b.c.d or as number of valid top-most bits. Default is
2066 10.0.2.0/24.
2068 @item host=@var{addr}
2069 Specify the guest-visible address of the host. Default is the 2nd IP in the
2070 guest network, i.e. x.x.x.2.
2072 @item ipv6-net=@var{addr}[/@var{int}]
2073 Set IPv6 network address the guest will see (default is fec0::/64). The
2074 network prefix is given in the usual hexadecimal IPv6 address
2075 notation. The prefix size is optional, and is given as the number of
2076 valid top-most bits (default is 64).
2078 @item ipv6-host=@var{addr}
2079 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2080 the guest network, i.e. xxxx::2.
2082 @item restrict=on|off
2083 If this option is enabled, the guest will be isolated, i.e. it will not be
2084 able to contact the host and no guest IP packets will be routed over the host
2085 to the outside. This option does not affect any explicitly set forwarding rules.
2087 @item hostname=@var{name}
2088 Specifies the client hostname reported by the built-in DHCP server.
2090 @item dhcpstart=@var{addr}
2091 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2092 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2094 @item dns=@var{addr}
2095 Specify the guest-visible address of the virtual nameserver. The address must
2096 be different from the host address. Default is the 3rd IP in the guest network,
2097 i.e. x.x.x.3.
2099 @item ipv6-dns=@var{addr}
2100 Specify the guest-visible address of the IPv6 virtual nameserver. The address
2101 must be different from the host address. Default is the 3rd IP in the guest
2102 network, i.e. xxxx::3.
2104 @item dnssearch=@var{domain}
2105 Provides an entry for the domain-search list sent by the built-in
2106 DHCP server. More than one domain suffix can be transmitted by specifying
2107 this option multiple times. If supported, this will cause the guest to
2108 automatically try to append the given domain suffix(es) in case a domain name
2109 can not be resolved.
2111 Example:
2112 @example
2113 qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org
2114 @end example
2116 @item domainname=@var{domain}
2117 Specifies the client domain name reported by the built-in DHCP server.
2119 @item tftp=@var{dir}
2120 When using the user mode network stack, activate a built-in TFTP
2121 server. The files in @var{dir} will be exposed as the root of a TFTP server.
2122 The TFTP client on the guest must be configured in binary mode (use the command
2123 @code{bin} of the Unix TFTP client).
2125 @item bootfile=@var{file}
2126 When using the user mode network stack, broadcast @var{file} as the BOOTP
2127 filename. In conjunction with @option{tftp}, this can be used to network boot
2128 a guest from a local directory.
2130 Example (using pxelinux):
2131 @example
2132 qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \
2133 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2134 @end example
2136 @item smb=@var{dir}[,smbserver=@var{addr}]
2137 When using the user mode network stack, activate a built-in SMB
2138 server so that Windows OSes can access to the host files in @file{@var{dir}}
2139 transparently. The IP address of the SMB server can be set to @var{addr}. By
2140 default the 4th IP in the guest network is used, i.e. x.x.x.4.
2142 In the guest Windows OS, the line:
2143 @example
2144 10.0.2.4 smbserver
2145 @end example
2146 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2147 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2149 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2151 Note that a SAMBA server must be installed on the host OS.
2153 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2154 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2155 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2156 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2157 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2158 be bound to a specific host interface. If no connection type is set, TCP is
2159 used. This option can be given multiple times.
2161 For example, to redirect host X11 connection from screen 1 to guest
2162 screen 0, use the following:
2164 @example
2165 # on the host
2166 qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000
2167 # this host xterm should open in the guest X11 server
2168 xterm -display :1
2169 @end example
2171 To redirect telnet connections from host port 5555 to telnet port on
2172 the guest, use the following:
2174 @example
2175 # on the host
2176 qemu-system-i386 -nic user,hostfwd=tcp::5555-:23
2177 telnet localhost 5555
2178 @end example
2180 Then when you use on the host @code{telnet localhost 5555}, you
2181 connect to the guest telnet server.
2183 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2184 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2185 Forward guest TCP connections to the IP address @var{server} on port @var{port}
2186 to the character device @var{dev} or to a program executed by @var{cmd:command}
2187 which gets spawned for each connection. This option can be given multiple times.
2189 You can either use a chardev directly and have that one used throughout QEMU's
2190 lifetime, like in the following example:
2192 @example
2193 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
2194 # the guest accesses it
2195 qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321
2196 @end example
2198 Or you can execute a command on every TCP connection established by the guest,
2199 so that QEMU behaves similar to an inetd process for that virtual server:
2201 @example
2202 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
2203 # and connect the TCP stream to its stdin/stdout
2204 qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2205 @end example
2207 @end table
2209 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
2210 processed and applied to -net user. Mixing them with the new configuration
2211 syntax gives undefined results. Their use for new applications is discouraged
2212 as they will be removed from future versions.
2214 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2215 Configure a host TAP network backend with ID @var{id}.
2217 Use the network script @var{file} to configure it and the network script
2218 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
2219 automatically provides one. The default network configure script is
2220 @file{/etc/qemu-ifup} and the default network deconfigure script is
2221 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
2222 to disable script execution.
2224 If running QEMU as an unprivileged user, use the network helper
2225 @var{helper} to configure the TAP interface and attach it to the bridge.
2226 The default network helper executable is @file{/path/to/qemu-bridge-helper}
2227 and the default bridge device is @file{br0}.
2229 @option{fd}=@var{h} can be used to specify the handle of an already
2230 opened host TAP interface.
2232 Examples:
2234 @example
2235 #launch a QEMU instance with the default network script
2236 qemu-system-i386 linux.img -nic tap
2237 @end example
2239 @example
2240 #launch a QEMU instance with two NICs, each one connected
2241 #to a TAP device
2242 qemu-system-i386 linux.img \
2243 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \
2244 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1
2245 @end example
2247 @example
2248 #launch a QEMU instance with the default network helper to
2249 #connect a TAP device to bridge br0
2250 qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \
2251 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper"
2252 @end example
2254 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
2255 Connect a host TAP network interface to a host bridge device.
2257 Use the network helper @var{helper} to configure the TAP interface and
2258 attach it to the bridge. The default network helper executable is
2259 @file{/path/to/qemu-bridge-helper} and the default bridge
2260 device is @file{br0}.
2262 Examples:
2264 @example
2265 #launch a QEMU instance with the default network helper to
2266 #connect a TAP device to bridge br0
2267 qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1
2268 @end example
2270 @example
2271 #launch a QEMU instance with the default network helper to
2272 #connect a TAP device to bridge qemubr0
2273 qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1
2274 @end example
2276 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2278 This host network backend can be used to connect the guest's network to
2279 another QEMU virtual machine using a TCP socket connection. If @option{listen}
2280 is specified, QEMU waits for incoming connections on @var{port}
2281 (@var{host} is optional). @option{connect} is used to connect to
2282 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
2283 specifies an already opened TCP socket.
2285 Example:
2286 @example
2287 # launch a first QEMU instance
2288 qemu-system-i386 linux.img \
2289 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2290 -netdev socket,id=n1,listen=:1234
2291 # connect the network of this instance to the network of the first instance
2292 qemu-system-i386 linux.img \
2293 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \
2294 -netdev socket,id=n2,connect=127.0.0.1:1234
2295 @end example
2297 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2299 Configure a socket host network backend to share the guest's network traffic
2300 with another QEMU virtual machines using a UDP multicast socket, effectively
2301 making a bus for every QEMU with same multicast address @var{maddr} and @var{port}.
2302 NOTES:
2303 @enumerate
2304 @item
2305 Several QEMU can be running on different hosts and share same bus (assuming
2306 correct multicast setup for these hosts).
2307 @item
2308 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
2309 @url{http://user-mode-linux.sf.net}.
2310 @item
2311 Use @option{fd=h} to specify an already opened UDP multicast socket.
2312 @end enumerate
2314 Example:
2315 @example
2316 # launch one QEMU instance
2317 qemu-system-i386 linux.img \
2318 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2319 -netdev socket,id=n1,mcast=230.0.0.1:1234
2320 # launch another QEMU instance on same "bus"
2321 qemu-system-i386 linux.img \
2322 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \
2323 -netdev socket,id=n2,mcast=230.0.0.1:1234
2324 # launch yet another QEMU instance on same "bus"
2325 qemu-system-i386 linux.img \
2326 -device e1000,netdev=n3,macaddr=52:54:00:12:34:58 \
2327 -netdev socket,id=n3,mcast=230.0.0.1:1234
2328 @end example
2330 Example (User Mode Linux compat.):
2331 @example
2332 # launch QEMU instance (note mcast address selected is UML's default)
2333 qemu-system-i386 linux.img \
2334 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2335 -netdev socket,id=n1,mcast=239.192.168.1:1102
2336 # launch UML
2337 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2338 @end example
2340 Example (send packets from host's 1.2.3.4):
2341 @example
2342 qemu-system-i386 linux.img \
2343 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2344 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2345 @end example
2347 @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}]
2348 Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a
2349 popular protocol to transport Ethernet (and other Layer 2) data frames between
2350 two systems. It is present in routers, firewalls and the Linux kernel
2351 (from version 3.3 onwards).
2353 This transport allows a VM to communicate to another VM, router or firewall directly.
2355 @table @option
2356 @item src=@var{srcaddr}
2357 source address (mandatory)
2358 @item dst=@var{dstaddr}
2359 destination address (mandatory)
2360 @item udp
2361 select udp encapsulation (default is ip).
2362 @item srcport=@var{srcport}
2363 source udp port.
2364 @item dstport=@var{dstport}
2365 destination udp port.
2366 @item ipv6
2367 force v6, otherwise defaults to v4.
2368 @item rxcookie=@var{rxcookie}
2369 @itemx txcookie=@var{txcookie}
2370 Cookies are a weak form of security in the l2tpv3 specification.
2371 Their function is mostly to prevent misconfiguration. By default they are 32
2372 bit.
2373 @item cookie64
2374 Set cookie size to 64 bit instead of the default 32
2375 @item counter=off
2376 Force a 'cut-down' L2TPv3 with no counter as in
2377 draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2378 @item pincounter=on
2379 Work around broken counter handling in peer. This may also help on
2380 networks which have packet reorder.
2381 @item offset=@var{offset}
2382 Add an extra offset between header and data
2383 @end table
2385 For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2386 on the remote Linux host 1.2.3.4:
2387 @example
2388 # Setup tunnel on linux host using raw ip as encapsulation
2389 # on 1.2.3.4
2390 ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2391 encap udp udp_sport 16384 udp_dport 16384
2392 ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2393 0xFFFFFFFF peer_session_id 0xFFFFFFFF
2394 ifconfig vmtunnel0 mtu 1500
2395 ifconfig vmtunnel0 up
2396 brctl addif br-lan vmtunnel0
2399 # on 4.3.2.1
2400 # launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2402 qemu-system-i386 linux.img -device e1000,netdev=n1 \
2403 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter
2405 @end example
2407 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2408 Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and
2409 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2410 and MODE @var{octalmode} to change default ownership and permissions for
2411 communication port. This option is only available if QEMU has been compiled
2412 with vde support enabled.
2414 Example:
2415 @example
2416 # launch vde switch
2417 vde_switch -F -sock /tmp/myswitch
2418 # launch QEMU instance
2419 qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch
2420 @end example
2422 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2424 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2425 be a unix domain socket backed one. The vhost-user uses a specifically defined
2426 protocol to pass vhost ioctl replacement messages to an application on the other
2427 end of the socket. On non-MSIX guests, the feature can be forced with
2428 @var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2429 be created for multiqueue vhost-user.
2431 Example:
2432 @example
2433 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2434 -numa node,memdev=mem \
2435 -chardev socket,id=chr0,path=/path/to/socket \
2436 -netdev type=vhost-user,id=net0,chardev=chr0 \
2437 -device virtio-net-pci,netdev=net0
2438 @end example
2440 @item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}]
2442 Create a hub port on the emulated hub with ID @var{hubid}.
2444 The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a
2445 single netdev. Alternatively, you can also connect the hubport to another
2446 netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option.
2448 @item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2449 @findex -net
2450 Legacy option to configure or create an on-board (or machine default) Network
2451 Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e.
2452 the default hub), or to the netdev @var{nd}.
2453 The NIC is an e1000 by default on the PC target. Optionally, the MAC address
2454 can be changed to @var{mac}, the device address set to @var{addr} (PCI cards
2455 only), and a @var{name} can be assigned for use in monitor commands.
2456 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2457 that the card should have; this option currently only affects virtio cards; set
2458 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2459 NIC is created. QEMU can emulate several different models of network card.
2460 Use @code{-net nic,model=help} for a list of available devices for your target.
2462 @item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}]
2463 Configure a host network backend (with the options corresponding to the same
2464 @option{-netdev} option) and connect it to the emulated hub 0 (the default
2465 hub). Use @var{name} to specify the name of the hub port.
2466 ETEXI
2468 STEXI
2469 @end table
2470 ETEXI
2471 DEFHEADING()
2473 DEFHEADING(Character device options:)
2475 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2476 "-chardev help\n"
2477 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2478 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2479 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2480 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2481 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2482 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2483 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2484 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2485 " [,logfile=PATH][,logappend=on|off]\n"
2486 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2487 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2488 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2489 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2490 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2491 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2492 #ifdef _WIN32
2493 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2494 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2495 #else
2496 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2497 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2498 #endif
2499 #ifdef CONFIG_BRLAPI
2500 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2501 #endif
2502 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2503 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2504 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2505 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2506 #endif
2507 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2508 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2509 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2510 #endif
2511 #if defined(CONFIG_SPICE)
2512 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2513 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2514 #endif
2515 , QEMU_ARCH_ALL
2518 STEXI
2520 The general form of a character device option is:
2521 @table @option
2522 @item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}]
2523 @findex -chardev
2524 Backend is one of:
2525 @option{null},
2526 @option{socket},
2527 @option{udp},
2528 @option{msmouse},
2529 @option{vc},
2530 @option{ringbuf},
2531 @option{file},
2532 @option{pipe},
2533 @option{console},
2534 @option{serial},
2535 @option{pty},
2536 @option{stdio},
2537 @option{braille},
2538 @option{tty},
2539 @option{parallel},
2540 @option{parport},
2541 @option{spicevmc},
2542 @option{spiceport}.
2543 The specific backend will determine the applicable options.
2545 Use @code{-chardev help} to print all available chardev backend types.
2547 All devices must have an id, which can be any string up to 127 characters long.
2548 It is used to uniquely identify this device in other command line directives.
2550 A character device may be used in multiplexing mode by multiple front-ends.
2551 Specify @option{mux=on} to enable this mode.
2552 A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2553 backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2554 If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2555 create a multiplexer with your specified ID, and you can then configure multiple
2556 front ends to use that chardev ID for their input/output. Up to four different
2557 front ends can be connected to a single multiplexed chardev. (Without
2558 multiplexing enabled, a chardev can only be used by a single front end.)
2559 For instance you could use this to allow a single stdio chardev to be used by
2560 two serial ports and the QEMU monitor:
2562 @example
2563 -chardev stdio,mux=on,id=char0 \
2564 -mon chardev=char0,mode=readline \
2565 -serial chardev:char0 \
2566 -serial chardev:char0
2567 @end example
2569 You can have more than one multiplexer in a system configuration; for instance
2570 you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2571 multiplexed between the QEMU monitor and a parallel port:
2573 @example
2574 -chardev stdio,mux=on,id=char0 \
2575 -mon chardev=char0,mode=readline \
2576 -parallel chardev:char0 \
2577 -chardev tcp,...,mux=on,id=char1 \
2578 -serial chardev:char1 \
2579 -serial chardev:char1
2580 @end example
2582 When you're using a multiplexed character device, some escape sequences are
2583 interpreted in the input. @xref{mux_keys, Keys in the character backend
2584 multiplexer}.
2586 Note that some other command line options may implicitly create multiplexed
2587 character backends; for instance @option{-serial mon:stdio} creates a
2588 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2589 and @option{-nographic} also multiplexes the console and the monitor to
2590 stdio.
2592 There is currently no support for multiplexing in the other direction
2593 (where a single QEMU front end takes input and output from multiple chardevs).
2595 Every backend supports the @option{logfile} option, which supplies the path
2596 to a file to record all data transmitted via the backend. The @option{logappend}
2597 option controls whether the log file will be truncated or appended to when
2598 opened.
2600 @end table
2602 The available backends are:
2604 @table @option
2605 @item -chardev null,id=@var{id}
2606 A void device. This device will not emit any data, and will drop any data it
2607 receives. The null backend does not take any options.
2609 @item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,reconnect=@var{seconds}][,tls-creds=@var{id}]
2611 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2612 unix socket will be created if @option{path} is specified. Behaviour is
2613 undefined if TCP options are specified for a unix socket.
2615 @option{server} specifies that the socket shall be a listening socket.
2617 @option{nowait} specifies that QEMU should not block waiting for a client to
2618 connect to a listening socket.
2620 @option{telnet} specifies that traffic on the socket should interpret telnet
2621 escape sequences.
2623 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2624 the remote end goes away. qemu will delay this many seconds and then attempt
2625 to reconnect. Zero disables reconnecting, and is the default.
2627 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2628 and specifies the id of the TLS credentials to use for the handshake. The
2629 credentials must be previously created with the @option{-object tls-creds}
2630 argument.
2632 TCP and unix socket options are given below:
2634 @table @option
2636 @item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay]
2638 @option{host} for a listening socket specifies the local address to be bound.
2639 For a connecting socket species the remote host to connect to. @option{host} is
2640 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2642 @option{port} for a listening socket specifies the local port to be bound. For a
2643 connecting socket specifies the port on the remote host to connect to.
2644 @option{port} can be given as either a port number or a service name.
2645 @option{port} is required.
2647 @option{to} is only relevant to listening sockets. If it is specified, and
2648 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2649 to and including @option{to} until it succeeds. @option{to} must be specified
2650 as a port number.
2652 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2653 If neither is specified the socket may use either protocol.
2655 @option{nodelay} disables the Nagle algorithm.
2657 @item unix options: path=@var{path}
2659 @option{path} specifies the local path of the unix socket. @option{path} is
2660 required.
2662 @end table
2664 @item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6]
2666 Sends all traffic from the guest to a remote host over UDP.
2668 @option{host} specifies the remote host to connect to. If not specified it
2669 defaults to @code{localhost}.
2671 @option{port} specifies the port on the remote host to connect to. @option{port}
2672 is required.
2674 @option{localaddr} specifies the local address to bind to. If not specified it
2675 defaults to @code{0.0.0.0}.
2677 @option{localport} specifies the local port to bind to. If not specified any
2678 available local port will be used.
2680 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2681 If neither is specified the device may use either protocol.
2683 @item -chardev msmouse,id=@var{id}
2685 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2686 take any options.
2688 @item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]]
2690 Connect to a QEMU text console. @option{vc} may optionally be given a specific
2691 size.
2693 @option{width} and @option{height} specify the width and height respectively of
2694 the console, in pixels.
2696 @option{cols} and @option{rows} specify that the console be sized to fit a text
2697 console with the given dimensions.
2699 @item -chardev ringbuf,id=@var{id}[,size=@var{size}]
2701 Create a ring buffer with fixed size @option{size}.
2702 @var{size} must be a power of two and defaults to @code{64K}.
2704 @item -chardev file,id=@var{id},path=@var{path}
2706 Log all traffic received from the guest to a file.
2708 @option{path} specifies the path of the file to be opened. This file will be
2709 created if it does not already exist, and overwritten if it does. @option{path}
2710 is required.
2712 @item -chardev pipe,id=@var{id},path=@var{path}
2714 Create a two-way connection to the guest. The behaviour differs slightly between
2715 Windows hosts and other hosts:
2717 On Windows, a single duplex pipe will be created at
2718 @file{\\.pipe\@option{path}}.
2720 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2721 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2722 received by the guest. Data written by the guest can be read from
2723 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2724 be present.
2726 @option{path} forms part of the pipe path as described above. @option{path} is
2727 required.
2729 @item -chardev console,id=@var{id}
2731 Send traffic from the guest to QEMU's standard output. @option{console} does not
2732 take any options.
2734 @option{console} is only available on Windows hosts.
2736 @item -chardev serial,id=@var{id},path=@option{path}
2738 Send traffic from the guest to a serial device on the host.
2740 On Unix hosts serial will actually accept any tty device,
2741 not only serial lines.
2743 @option{path} specifies the name of the serial device to open.
2745 @item -chardev pty,id=@var{id}
2747 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2748 not take any options.
2750 @option{pty} is not available on Windows hosts.
2752 @item -chardev stdio,id=@var{id}[,signal=on|off]
2753 Connect to standard input and standard output of the QEMU process.
2755 @option{signal} controls if signals are enabled on the terminal, that includes
2756 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2757 default, use @option{signal=off} to disable it.
2759 @item -chardev braille,id=@var{id}
2761 Connect to a local BrlAPI server. @option{braille} does not take any options.
2763 @item -chardev tty,id=@var{id},path=@var{path}
2765 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2766 DragonFlyBSD hosts. It is an alias for @option{serial}.
2768 @option{path} specifies the path to the tty. @option{path} is required.
2770 @item -chardev parallel,id=@var{id},path=@var{path}
2771 @itemx -chardev parport,id=@var{id},path=@var{path}
2773 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2775 Connect to a local parallel port.
2777 @option{path} specifies the path to the parallel port device. @option{path} is
2778 required.
2780 @item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name}
2782 @option{spicevmc} is only available when spice support is built in.
2784 @option{debug} debug level for spicevmc
2786 @option{name} name of spice channel to connect to
2788 Connect to a spice virtual machine channel, such as vdiport.
2790 @item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name}
2792 @option{spiceport} is only available when spice support is built in.
2794 @option{debug} debug level for spicevmc
2796 @option{name} name of spice port to connect to
2798 Connect to a spice port, allowing a Spice client to handle the traffic
2799 identified by a name (preferably a fqdn).
2800 ETEXI
2802 STEXI
2803 @end table
2804 ETEXI
2805 DEFHEADING()
2807 DEFHEADING(Bluetooth(R) options:)
2808 STEXI
2809 @table @option
2810 ETEXI
2812 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2813 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2814 "-bt hci,host[:id]\n" \
2815 " use host's HCI with the given name\n" \
2816 "-bt hci[,vlan=n]\n" \
2817 " emulate a standard HCI in virtual scatternet 'n'\n" \
2818 "-bt vhci[,vlan=n]\n" \
2819 " add host computer to virtual scatternet 'n' using VHCI\n" \
2820 "-bt device:dev[,vlan=n]\n" \
2821 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2822 QEMU_ARCH_ALL)
2823 STEXI
2824 @item -bt hci[...]
2825 @findex -bt
2826 Defines the function of the corresponding Bluetooth HCI. -bt options
2827 are matched with the HCIs present in the chosen machine type. For
2828 example when emulating a machine with only one HCI built into it, only
2829 the first @code{-bt hci[...]} option is valid and defines the HCI's
2830 logic. The Transport Layer is decided by the machine type. Currently
2831 the machines @code{n800} and @code{n810} have one HCI and all other
2832 machines have none.
2834 @anchor{bt-hcis}
2835 The following three types are recognized:
2837 @table @option
2838 @item -bt hci,null
2839 (default) The corresponding Bluetooth HCI assumes no internal logic
2840 and will not respond to any HCI commands or emit events.
2842 @item -bt hci,host[:@var{id}]
2843 (@code{bluez} only) The corresponding HCI passes commands / events
2844 to / from the physical HCI identified by the name @var{id} (default:
2845 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2846 capable systems like Linux.
2848 @item -bt hci[,vlan=@var{n}]
2849 Add a virtual, standard HCI that will participate in the Bluetooth
2850 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2851 VLANs, devices inside a bluetooth network @var{n} can only communicate
2852 with other devices in the same network (scatternet).
2853 @end table
2855 @item -bt vhci[,vlan=@var{n}]
2856 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2857 to the host bluetooth stack instead of to the emulated target. This
2858 allows the host and target machines to participate in a common scatternet
2859 and communicate. Requires the Linux @code{vhci} driver installed. Can
2860 be used as following:
2862 @example
2863 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2864 @end example
2866 @item -bt device:@var{dev}[,vlan=@var{n}]
2867 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2868 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2869 currently:
2871 @table @option
2872 @item keyboard
2873 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2874 @end table
2875 ETEXI
2877 STEXI
2878 @end table
2879 ETEXI
2880 DEFHEADING()
2882 #ifdef CONFIG_TPM
2883 DEFHEADING(TPM device options:)
2885 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2886 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2887 " use path to provide path to a character device; default is /dev/tpm0\n"
2888 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2889 " not provided it will be searched for in /sys/class/misc/tpm?/device\n"
2890 "-tpmdev emulator,id=id,chardev=dev\n"
2891 " configure the TPM device using chardev backend\n",
2892 QEMU_ARCH_ALL)
2893 STEXI
2895 The general form of a TPM device option is:
2896 @table @option
2898 @item -tpmdev @var{backend},id=@var{id}[,@var{options}]
2899 @findex -tpmdev
2901 The specific backend type will determine the applicable options.
2902 The @code{-tpmdev} option creates the TPM backend and requires a
2903 @code{-device} option that specifies the TPM frontend interface model.
2905 Use @code{-tpmdev help} to print all available TPM backend types.
2907 @end table
2909 The available backends are:
2911 @table @option
2913 @item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path}
2915 (Linux-host only) Enable access to the host's TPM using the passthrough
2916 driver.
2918 @option{path} specifies the path to the host's TPM device, i.e., on
2919 a Linux host this would be @code{/dev/tpm0}.
2920 @option{path} is optional and by default @code{/dev/tpm0} is used.
2922 @option{cancel-path} specifies the path to the host TPM device's sysfs
2923 entry allowing for cancellation of an ongoing TPM command.
2924 @option{cancel-path} is optional and by default QEMU will search for the
2925 sysfs entry to use.
2927 Some notes about using the host's TPM with the passthrough driver:
2929 The TPM device accessed by the passthrough driver must not be
2930 used by any other application on the host.
2932 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2933 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2934 TPM again and may therefore not show a TPM-specific menu that would
2935 otherwise allow the user to configure the TPM, e.g., allow the user to
2936 enable/disable or activate/deactivate the TPM.
2937 Further, if TPM ownership is released from within a VM then the host's TPM
2938 will get disabled and deactivated. To enable and activate the
2939 TPM again afterwards, the host has to be rebooted and the user is
2940 required to enter the firmware's menu to enable and activate the TPM.
2941 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2943 To create a passthrough TPM use the following two options:
2944 @example
2945 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2946 @end example
2947 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2948 @code{tpmdev=tpm0} in the device option.
2950 @item -tpmdev emulator,id=@var{id},chardev=@var{dev}
2952 (Linux-host only) Enable access to a TPM emulator using Unix domain socket based
2953 chardev backend.
2955 @option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
2957 To create a TPM emulator backend device with chardev socket backend:
2958 @example
2960 -chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
2962 @end example
2964 ETEXI
2966 STEXI
2967 @end table
2968 ETEXI
2969 DEFHEADING()
2971 #endif
2973 DEFHEADING(Linux/Multiboot boot specific:)
2974 STEXI
2976 When using these options, you can use a given Linux or Multiboot
2977 kernel without installing it in the disk image. It can be useful
2978 for easier testing of various kernels.
2980 @table @option
2981 ETEXI
2983 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2984 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2985 STEXI
2986 @item -kernel @var{bzImage}
2987 @findex -kernel
2988 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2989 or in multiboot format.
2990 ETEXI
2992 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2993 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2994 STEXI
2995 @item -append @var{cmdline}
2996 @findex -append
2997 Use @var{cmdline} as kernel command line
2998 ETEXI
3000 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
3001 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
3002 STEXI
3003 @item -initrd @var{file}
3004 @findex -initrd
3005 Use @var{file} as initial ram disk.
3007 @item -initrd "@var{file1} arg=foo,@var{file2}"
3009 This syntax is only available with multiboot.
3011 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3012 first module.
3013 ETEXI
3015 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
3016 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
3017 STEXI
3018 @item -dtb @var{file}
3019 @findex -dtb
3020 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3021 on boot.
3022 ETEXI
3024 STEXI
3025 @end table
3026 ETEXI
3027 DEFHEADING()
3029 DEFHEADING(Debug/Expert options:)
3030 STEXI
3031 @table @option
3032 ETEXI
3034 DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
3035 "-fw_cfg [name=]<name>,file=<file>\n"
3036 " add named fw_cfg entry with contents from file\n"
3037 "-fw_cfg [name=]<name>,string=<str>\n"
3038 " add named fw_cfg entry with contents from string\n",
3039 QEMU_ARCH_ALL)
3040 STEXI
3042 @item -fw_cfg [name=]@var{name},file=@var{file}
3043 @findex -fw_cfg
3044 Add named fw_cfg entry with contents from file @var{file}.
3046 @item -fw_cfg [name=]@var{name},string=@var{str}
3047 Add named fw_cfg entry with contents from string @var{str}.
3049 The terminating NUL character of the contents of @var{str} will not be
3050 included as part of the fw_cfg item data. To insert contents with
3051 embedded NUL characters, you have to use the @var{file} parameter.
3053 The fw_cfg entries are passed by QEMU through to the guest.
3055 Example:
3056 @example
3057 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3058 @end example
3059 creates an fw_cfg entry named opt/com.mycompany/blob with contents
3060 from ./my_blob.bin.
3062 ETEXI
3064 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
3065 "-serial dev redirect the serial port to char device 'dev'\n",
3066 QEMU_ARCH_ALL)
3067 STEXI
3068 @item -serial @var{dev}
3069 @findex -serial
3070 Redirect the virtual serial port to host character device
3071 @var{dev}. The default device is @code{vc} in graphical mode and
3072 @code{stdio} in non graphical mode.
3074 This option can be used several times to simulate up to 4 serial
3075 ports.
3077 Use @code{-serial none} to disable all serial ports.
3079 Available character devices are:
3080 @table @option
3081 @item vc[:@var{W}x@var{H}]
3082 Virtual console. Optionally, a width and height can be given in pixel with
3083 @example
3084 vc:800x600
3085 @end example
3086 It is also possible to specify width or height in characters:
3087 @example
3088 vc:80Cx24C
3089 @end example
3090 @item pty
3091 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
3092 @item none
3093 No device is allocated.
3094 @item null
3095 void device
3096 @item chardev:@var{id}
3097 Use a named character device defined with the @code{-chardev} option.
3098 @item /dev/XXX
3099 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3100 parameters are set according to the emulated ones.
3101 @item /dev/parport@var{N}
3102 [Linux only, parallel port only] Use host parallel port
3103 @var{N}. Currently SPP and EPP parallel port features can be used.
3104 @item file:@var{filename}
3105 Write output to @var{filename}. No character can be read.
3106 @item stdio
3107 [Unix only] standard input/output
3108 @item pipe:@var{filename}
3109 name pipe @var{filename}
3110 @item COM@var{n}
3111 [Windows only] Use host serial port @var{n}
3112 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3113 This implements UDP Net Console.
3114 When @var{remote_host} or @var{src_ip} are not specified
3115 they default to @code{0.0.0.0}.
3116 When not using a specified @var{src_port} a random port is automatically chosen.
3118 If you just want a simple readonly console you can use @code{netcat} or
3119 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3120 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3121 will appear in the netconsole session.
3123 If you plan to send characters back via netconsole or you want to stop
3124 and start QEMU a lot of times, you should have QEMU use the same
3125 source port each time by using something like @code{-serial
3126 udp::4555@@:4556} to QEMU. Another approach is to use a patched
3127 version of netcat which can listen to a TCP port and send and receive
3128 characters via udp. If you have a patched version of netcat which
3129 activates telnet remote echo and single char transfer, then you can
3130 use the following options to set up a netcat redirector to allow
3131 telnet on port 5555 to access the QEMU port.
3132 @table @code
3133 @item QEMU Options:
3134 -serial udp::4555@@:4556
3135 @item netcat options:
3136 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3137 @item telnet options:
3138 localhost 5555
3139 @end table
3141 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3142 The TCP Net Console has two modes of operation. It can send the serial
3143 I/O to a location or wait for a connection from a location. By default
3144 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
3145 the @var{server} option QEMU will wait for a client socket application
3146 to connect to the port before continuing, unless the @code{nowait}
3147 option was specified. The @code{nodelay} option disables the Nagle buffering
3148 algorithm. The @code{reconnect} option only applies if @var{noserver} is
3149 set, if the connection goes down it will attempt to reconnect at the
3150 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
3151 one TCP connection at a time is accepted. You can use @code{telnet} to
3152 connect to the corresponding character device.
3153 @table @code
3154 @item Example to send tcp console to 192.168.0.2 port 4444
3155 -serial tcp:192.168.0.2:4444
3156 @item Example to listen and wait on port 4444 for connection
3157 -serial tcp::4444,server
3158 @item Example to not wait and listen on ip 192.168.0.100 port 4444
3159 -serial tcp:192.168.0.100:4444,server,nowait
3160 @end table
3162 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3163 The telnet protocol is used instead of raw tcp sockets. The options
3164 work the same as if you had specified @code{-serial tcp}. The
3165 difference is that the port acts like a telnet server or client using
3166 telnet option negotiation. This will also allow you to send the
3167 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3168 sequence. Typically in unix telnet you do it with Control-] and then
3169 type "send break" followed by pressing the enter key.
3171 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3172 A unix domain socket is used instead of a tcp socket. The option works the
3173 same as if you had specified @code{-serial tcp} except the unix domain socket
3174 @var{path} is used for connections.
3176 @item mon:@var{dev_string}
3177 This is a special option to allow the monitor to be multiplexed onto
3178 another serial port. The monitor is accessed with key sequence of
3179 @key{Control-a} and then pressing @key{c}.
3180 @var{dev_string} should be any one of the serial devices specified
3181 above. An example to multiplex the monitor onto a telnet server
3182 listening on port 4444 would be:
3183 @table @code
3184 @item -serial mon:telnet::4444,server,nowait
3185 @end table
3186 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3187 QEMU any more but will be passed to the guest instead.
3189 @item braille
3190 Braille device. This will use BrlAPI to display the braille output on a real
3191 or fake device.
3193 @item msmouse
3194 Three button serial mouse. Configure the guest to use Microsoft protocol.
3195 @end table
3196 ETEXI
3198 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3199 "-parallel dev redirect the parallel port to char device 'dev'\n",
3200 QEMU_ARCH_ALL)
3201 STEXI
3202 @item -parallel @var{dev}
3203 @findex -parallel
3204 Redirect the virtual parallel port to host device @var{dev} (same
3205 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3206 be used to use hardware devices connected on the corresponding host
3207 parallel port.
3209 This option can be used several times to simulate up to 3 parallel
3210 ports.
3212 Use @code{-parallel none} to disable all parallel ports.
3213 ETEXI
3215 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3216 "-monitor dev redirect the monitor to char device 'dev'\n",
3217 QEMU_ARCH_ALL)
3218 STEXI
3219 @item -monitor @var{dev}
3220 @findex -monitor
3221 Redirect the monitor to host device @var{dev} (same devices as the
3222 serial port).
3223 The default device is @code{vc} in graphical mode and @code{stdio} in
3224 non graphical mode.
3225 Use @code{-monitor none} to disable the default monitor.
3226 ETEXI
3227 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3228 "-qmp dev like -monitor but opens in 'control' mode\n",
3229 QEMU_ARCH_ALL)
3230 STEXI
3231 @item -qmp @var{dev}
3232 @findex -qmp
3233 Like -monitor but opens in 'control' mode.
3234 ETEXI
3235 DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3236 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3237 QEMU_ARCH_ALL)
3238 STEXI
3239 @item -qmp-pretty @var{dev}
3240 @findex -qmp-pretty
3241 Like -qmp but uses pretty JSON formatting.
3242 ETEXI
3244 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3245 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL)
3246 STEXI
3247 @item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]
3248 @findex -mon
3249 Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing
3250 easing human reading and debugging.
3251 ETEXI
3253 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3254 "-debugcon dev redirect the debug console to char device 'dev'\n",
3255 QEMU_ARCH_ALL)
3256 STEXI
3257 @item -debugcon @var{dev}
3258 @findex -debugcon
3259 Redirect the debug console to host device @var{dev} (same devices as the
3260 serial port). The debug console is an I/O port which is typically port
3261 0xe9; writing to that I/O port sends output to this device.
3262 The default device is @code{vc} in graphical mode and @code{stdio} in
3263 non graphical mode.
3264 ETEXI
3266 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3267 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
3268 STEXI
3269 @item -pidfile @var{file}
3270 @findex -pidfile
3271 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3272 from a script.
3273 ETEXI
3275 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3276 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
3277 STEXI
3278 @item -singlestep
3279 @findex -singlestep
3280 Run the emulation in single step mode.
3281 ETEXI
3283 DEF("preconfig", 0, QEMU_OPTION_preconfig, \
3284 "--preconfig pause QEMU before machine is initialized (experimental)\n",
3285 QEMU_ARCH_ALL)
3286 STEXI
3287 @item --preconfig
3288 @findex --preconfig
3289 Pause QEMU for interactive configuration before the machine is created,
3290 which allows querying and configuring properties that will affect
3291 machine initialization. Use QMP command 'x-exit-preconfig' to exit
3292 the preconfig state and move to the next state (i.e. run guest if -S
3293 isn't used or pause the second time if -S is used). This option is
3294 experimental.
3295 ETEXI
3297 DEF("S", 0, QEMU_OPTION_S, \
3298 "-S freeze CPU at startup (use 'c' to start execution)\n",
3299 QEMU_ARCH_ALL)
3300 STEXI
3301 @item -S
3302 @findex -S
3303 Do not start CPU at startup (you must type 'c' in the monitor).
3304 ETEXI
3306 DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3307 "-realtime [mlock=on|off]\n"
3308 " run qemu with realtime features\n"
3309 " mlock=on|off controls mlock support (default: on)\n",
3310 QEMU_ARCH_ALL)
3311 STEXI
3312 @item -realtime mlock=on|off
3313 @findex -realtime
3314 Run qemu with realtime features.
3315 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3316 (enabled by default).
3317 ETEXI
3319 DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit,
3320 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n"
3321 " run qemu with overcommit hints\n"
3322 " mem-lock=on|off controls memory lock support (default: off)\n"
3323 " cpu-pm=on|off controls cpu power management (default: off)\n",
3324 QEMU_ARCH_ALL)
3325 STEXI
3326 @item -overcommit mem-lock=on|off
3327 @item -overcommit cpu-pm=on|off
3328 @findex -overcommit
3329 Run qemu with hints about host resource overcommit. The default is
3330 to assume that host overcommits all resources.
3332 Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled
3333 by default). This works when host memory is not overcommitted and reduces the
3334 worst-case latency for guest. This is equivalent to @option{realtime}.
3336 Guest ability to manage power state of host cpus (increasing latency for other
3337 processes on the same host cpu, but decreasing latency for guest) can be
3338 enabled via @option{cpu-pm=on} (disabled by default). This works best when
3339 host CPU is not overcommitted. When used, host estimates of CPU cycle and power
3340 utilization will be incorrect, not taking into account guest idle time.
3341 ETEXI
3343 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3344 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3345 STEXI
3346 @item -gdb @var{dev}
3347 @findex -gdb
3348 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3349 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3350 stdio are reasonable use case. The latter is allowing to start QEMU from
3351 within gdb and establish the connection via a pipe:
3352 @example
3353 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3354 @end example
3355 ETEXI
3357 DEF("s", 0, QEMU_OPTION_s, \
3358 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3359 QEMU_ARCH_ALL)
3360 STEXI
3361 @item -s
3362 @findex -s
3363 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3364 (@pxref{gdb_usage}).
3365 ETEXI
3367 DEF("d", HAS_ARG, QEMU_OPTION_d, \
3368 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
3369 QEMU_ARCH_ALL)
3370 STEXI
3371 @item -d @var{item1}[,...]
3372 @findex -d
3373 Enable logging of specified items. Use '-d help' for a list of log items.
3374 ETEXI
3376 DEF("D", HAS_ARG, QEMU_OPTION_D, \
3377 "-D logfile output log to logfile (default stderr)\n",
3378 QEMU_ARCH_ALL)
3379 STEXI
3380 @item -D @var{logfile}
3381 @findex -D
3382 Output log in @var{logfile} instead of to stderr
3383 ETEXI
3385 DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3386 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3387 QEMU_ARCH_ALL)
3388 STEXI
3389 @item -dfilter @var{range1}[,...]
3390 @findex -dfilter
3391 Filter debug output to that relevant to a range of target addresses. The filter
3392 spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3393 @var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3394 addresses and sizes required. For example:
3395 @example
3396 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3397 @end example
3398 Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3399 the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3400 block starting at 0xffffffc00005f000.
3401 ETEXI
3403 DEF("L", HAS_ARG, QEMU_OPTION_L, \
3404 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
3405 QEMU_ARCH_ALL)
3406 STEXI
3407 @item -L @var{path}
3408 @findex -L
3409 Set the directory for the BIOS, VGA BIOS and keymaps.
3411 To list all the data directories, use @code{-L help}.
3412 ETEXI
3414 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3415 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
3416 STEXI
3417 @item -bios @var{file}
3418 @findex -bios
3419 Set the filename for the BIOS.
3420 ETEXI
3422 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3423 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3424 STEXI
3425 @item -enable-kvm
3426 @findex -enable-kvm
3427 Enable KVM full virtualization support. This option is only available
3428 if KVM support is enabled when compiling.
3429 ETEXI
3431 DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3432 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386)
3433 STEXI
3434 @item -enable-hax
3435 @findex -enable-hax
3436 Enable HAX (Hardware-based Acceleration eXecution) support. This option
3437 is only available if HAX support is enabled when compiling. HAX is only
3438 applicable to MAC and Windows platform, and thus does not conflict with
3439 KVM. This option is deprecated, use @option{-accel hax} instead.
3440 ETEXI
3442 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3443 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
3444 DEF("xen-create", 0, QEMU_OPTION_xen_create,
3445 "-xen-create create domain using xen hypercalls, bypassing xend\n"
3446 " warning: should not be used when xend is in use\n",
3447 QEMU_ARCH_ALL)
3448 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3449 "-xen-attach attach to existing xen domain\n"
3450 " xend will use this when starting QEMU\n",
3451 QEMU_ARCH_ALL)
3452 DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
3453 "-xen-domid-restrict restrict set of available xen operations\n"
3454 " to specified domain id. (Does not affect\n"
3455 " xenpv machine type).\n",
3456 QEMU_ARCH_ALL)
3457 STEXI
3458 @item -xen-domid @var{id}
3459 @findex -xen-domid
3460 Specify xen guest domain @var{id} (XEN only).
3461 @item -xen-create
3462 @findex -xen-create
3463 Create domain using xen hypercalls, bypassing xend.
3464 Warning: should not be used when xend is in use (XEN only).
3465 @item -xen-attach
3466 @findex -xen-attach
3467 Attach to existing xen domain.
3468 xend will use this when starting QEMU (XEN only).
3469 @findex -xen-domid-restrict
3470 Restrict set of available xen operations to specified domain id (XEN only).
3471 ETEXI
3473 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3474 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
3475 STEXI
3476 @item -no-reboot
3477 @findex -no-reboot
3478 Exit instead of rebooting.
3479 ETEXI
3481 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3482 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
3483 STEXI
3484 @item -no-shutdown
3485 @findex -no-shutdown
3486 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3487 This allows for instance switching to monitor to commit changes to the
3488 disk image.
3489 ETEXI
3491 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3492 "-loadvm [tag|id]\n" \
3493 " start right away with a saved state (loadvm in monitor)\n",
3494 QEMU_ARCH_ALL)
3495 STEXI
3496 @item -loadvm @var{file}
3497 @findex -loadvm
3498 Start right away with a saved state (@code{loadvm} in monitor)
3499 ETEXI
3501 #ifndef _WIN32
3502 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3503 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3504 #endif
3505 STEXI
3506 @item -daemonize
3507 @findex -daemonize
3508 Daemonize the QEMU process after initialization. QEMU will not detach from
3509 standard IO until it is ready to receive connections on any of its devices.
3510 This option is a useful way for external programs to launch QEMU without having
3511 to cope with initialization race conditions.
3512 ETEXI
3514 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3515 "-option-rom rom load a file, rom, into the option ROM space\n",
3516 QEMU_ARCH_ALL)
3517 STEXI
3518 @item -option-rom @var{file}
3519 @findex -option-rom
3520 Load the contents of @var{file} as an option ROM.
3521 This option is useful to load things like EtherBoot.
3522 ETEXI
3524 HXCOMM Silently ignored for compatibility
3525 DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3527 HXCOMM Options deprecated by -rtc
3528 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3529 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3531 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3532 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3533 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3534 QEMU_ARCH_ALL)
3536 STEXI
3538 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3539 @findex -rtc
3540 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3541 UTC or local time, respectively. @code{localtime} is required for correct date in
3542 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3543 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3545 By default the RTC is driven by the host system time. This allows using of the
3546 RTC as accurate reference clock inside the guest, specifically if the host
3547 time is smoothly following an accurate external reference clock, e.g. via NTP.
3548 If you want to isolate the guest time from the host, you can set @option{clock}
3549 to @code{rt} instead. To even prevent it from progressing during suspension,
3550 you can set it to @code{vm}.
3552 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3553 specifically with Windows' ACPI HAL. This option will try to figure out how
3554 many timer interrupts were not processed by the Windows guest and will
3555 re-inject them.
3556 ETEXI
3558 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3559 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3560 " enable virtual instruction counter with 2^N clock ticks per\n" \
3561 " instruction, enable aligning the host and virtual clocks\n" \
3562 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3563 STEXI
3564 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3565 @findex -icount
3566 Enable virtual instruction counter. The virtual cpu will execute one
3567 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3568 then the virtual cpu speed will be automatically adjusted to keep virtual
3569 time within a few seconds of real time.
3571 When the virtual cpu is sleeping, the virtual time will advance at default
3572 speed unless @option{sleep=on|off} is specified.
3573 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3574 instantly whenever the virtual cpu goes to sleep mode and will not advance
3575 if no timer is enabled. This behavior give deterministic execution times from
3576 the guest point of view.
3578 Note that while this option can give deterministic behavior, it does not
3579 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3580 order cores with complex cache hierarchies. The number of instructions
3581 executed often has little or no correlation with actual performance.
3583 @option{align=on} will activate the delay algorithm which will try
3584 to synchronise the host clock and the virtual clock. The goal is to
3585 have a guest running at the real frequency imposed by the shift option.
3586 Whenever the guest clock is behind the host clock and if
3587 @option{align=on} is specified then we print a message to the user
3588 to inform about the delay.
3589 Currently this option does not work when @option{shift} is @code{auto}.
3590 Note: The sync algorithm will work for those shift values for which
3591 the guest clock runs ahead of the host clock. Typically this happens
3592 when the shift value is high (how high depends on the host machine).
3594 When @option{rr} option is specified deterministic record/replay is enabled.
3595 Replay log is written into @var{filename} file in record mode and
3596 read from this file in replay mode.
3598 Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3599 at the start of execution recording. In replay mode this option is used
3600 to load the initial VM state.
3601 ETEXI
3603 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3604 "-watchdog model\n" \
3605 " enable virtual hardware watchdog [default=none]\n",
3606 QEMU_ARCH_ALL)
3607 STEXI
3608 @item -watchdog @var{model}
3609 @findex -watchdog
3610 Create a virtual hardware watchdog device. Once enabled (by a guest
3611 action), the watchdog must be periodically polled by an agent inside
3612 the guest or else the guest will be restarted. Choose a model for
3613 which your guest has drivers.
3615 The @var{model} is the model of hardware watchdog to emulate. Use
3616 @code{-watchdog help} to list available hardware models. Only one
3617 watchdog can be enabled for a guest.
3619 The following models may be available:
3620 @table @option
3621 @item ib700
3622 iBASE 700 is a very simple ISA watchdog with a single timer.
3623 @item i6300esb
3624 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3625 dual-timer watchdog.
3626 @item diag288
3627 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3628 (currently KVM only).
3629 @end table
3630 ETEXI
3632 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3633 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \
3634 " action when watchdog fires [default=reset]\n",
3635 QEMU_ARCH_ALL)
3636 STEXI
3637 @item -watchdog-action @var{action}
3638 @findex -watchdog-action
3640 The @var{action} controls what QEMU will do when the watchdog timer
3641 expires.
3642 The default is
3643 @code{reset} (forcefully reset the guest).
3644 Other possible actions are:
3645 @code{shutdown} (attempt to gracefully shutdown the guest),
3646 @code{poweroff} (forcefully poweroff the guest),
3647 @code{inject-nmi} (inject a NMI into the guest),
3648 @code{pause} (pause the guest),
3649 @code{debug} (print a debug message and continue), or
3650 @code{none} (do nothing).
3652 Note that the @code{shutdown} action requires that the guest responds
3653 to ACPI signals, which it may not be able to do in the sort of
3654 situations where the watchdog would have expired, and thus
3655 @code{-watchdog-action shutdown} is not recommended for production use.
3657 Examples:
3659 @table @code
3660 @item -watchdog i6300esb -watchdog-action pause
3661 @itemx -watchdog ib700
3662 @end table
3663 ETEXI
3665 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3666 "-echr chr set terminal escape character instead of ctrl-a\n",
3667 QEMU_ARCH_ALL)
3668 STEXI
3670 @item -echr @var{numeric_ascii_value}
3671 @findex -echr
3672 Change the escape character used for switching to the monitor when using
3673 monitor and serial sharing. The default is @code{0x01} when using the
3674 @code{-nographic} option. @code{0x01} is equal to pressing
3675 @code{Control-a}. You can select a different character from the ascii
3676 control keys where 1 through 26 map to Control-a through Control-z. For
3677 instance you could use the either of the following to change the escape
3678 character to Control-t.
3679 @table @code
3680 @item -echr 0x14
3681 @itemx -echr 20
3682 @end table
3683 ETEXI
3685 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3686 "-virtioconsole c\n" \
3687 " set virtio console\n", QEMU_ARCH_ALL)
3688 STEXI
3689 @item -virtioconsole @var{c}
3690 @findex -virtioconsole
3691 Set virtio console.
3692 This option is deprecated, please use @option{-device virtconsole} instead.
3693 ETEXI
3695 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3696 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3697 STEXI
3698 @item -show-cursor
3699 @findex -show-cursor
3700 Show cursor.
3701 ETEXI
3703 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3704 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3705 STEXI
3706 @item -tb-size @var{n}
3707 @findex -tb-size
3708 Set TB size.
3709 ETEXI
3711 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3712 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3713 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3714 "-incoming unix:socketpath\n" \
3715 " prepare for incoming migration, listen on\n" \
3716 " specified protocol and socket address\n" \
3717 "-incoming fd:fd\n" \
3718 "-incoming exec:cmdline\n" \
3719 " accept incoming migration on given file descriptor\n" \
3720 " or from given external command\n" \
3721 "-incoming defer\n" \
3722 " wait for the URI to be specified via migrate_incoming\n",
3723 QEMU_ARCH_ALL)
3724 STEXI
3725 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3726 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3727 @findex -incoming
3728 Prepare for incoming migration, listen on a given tcp port.
3730 @item -incoming unix:@var{socketpath}
3731 Prepare for incoming migration, listen on a given unix socket.
3733 @item -incoming fd:@var{fd}
3734 Accept incoming migration from a given filedescriptor.
3736 @item -incoming exec:@var{cmdline}
3737 Accept incoming migration as an output from specified external command.
3739 @item -incoming defer
3740 Wait for the URI to be specified via migrate_incoming. The monitor can
3741 be used to change settings (such as migration parameters) prior to issuing
3742 the migrate_incoming to allow the migration to begin.
3743 ETEXI
3745 DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \
3746 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL)
3747 STEXI
3748 @item -only-migratable
3749 @findex -only-migratable
3750 Only allow migratable devices. Devices will not be allowed to enter an
3751 unmigratable state.
3752 ETEXI
3754 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3755 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
3756 STEXI
3757 @item -nodefaults
3758 @findex -nodefaults
3759 Don't create default devices. Normally, QEMU sets the default devices like serial
3760 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3761 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3762 default devices.
3763 ETEXI
3765 #ifndef _WIN32
3766 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3767 "-chroot dir chroot to dir just before starting the VM\n",
3768 QEMU_ARCH_ALL)
3769 #endif
3770 STEXI
3771 @item -chroot @var{dir}
3772 @findex -chroot
3773 Immediately before starting guest execution, chroot to the specified
3774 directory. Especially useful in combination with -runas.
3775 ETEXI
3777 #ifndef _WIN32
3778 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3779 "-runas user change to user id user just before starting the VM\n" \
3780 " user can be numeric uid:gid instead\n",
3781 QEMU_ARCH_ALL)
3782 #endif
3783 STEXI
3784 @item -runas @var{user}
3785 @findex -runas
3786 Immediately before starting guest execution, drop root privileges, switching
3787 to the specified user.
3788 ETEXI
3790 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3791 "-prom-env variable=value\n"
3792 " set OpenBIOS nvram variables\n",
3793 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3794 STEXI
3795 @item -prom-env @var{variable}=@var{value}
3796 @findex -prom-env
3797 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3798 ETEXI
3799 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3800 "-semihosting semihosting mode\n",
3801 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3802 QEMU_ARCH_MIPS)
3803 STEXI
3804 @item -semihosting
3805 @findex -semihosting
3806 Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3807 ETEXI
3808 DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3809 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3810 " semihosting configuration\n",
3811 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3812 QEMU_ARCH_MIPS)
3813 STEXI
3814 @item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3815 @findex -semihosting-config
3816 Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3817 @table @option
3818 @item target=@code{native|gdb|auto}
3819 Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3820 or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3821 during debug sessions and @code{native} otherwise.
3822 @item arg=@var{str1},arg=@var{str2},...
3823 Allows the user to pass input arguments, and can be used multiple times to build
3824 up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3825 command line is still supported for backward compatibility. If both the
3826 @code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3827 specified, the former is passed to semihosting as it always takes precedence.
3828 @end table
3829 ETEXI
3830 DEF("old-param", 0, QEMU_OPTION_old_param,
3831 "-old-param old param mode\n", QEMU_ARCH_ARM)
3832 STEXI
3833 @item -old-param
3834 @findex -old-param (ARM)
3835 Old param mode (ARM only).
3836 ETEXI
3838 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3839 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
3840 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
3841 " Enable seccomp mode 2 system call filter (default 'off').\n" \
3842 " use 'obsolete' to allow obsolete system calls that are provided\n" \
3843 " by the kernel, but typically no longer used by modern\n" \
3844 " C library implementations.\n" \
3845 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \
3846 " its privileges by blacklisting all set*uid|gid system calls.\n" \
3847 " The value 'children' will deny set*uid|gid system calls for\n" \
3848 " main QEMU process but will allow forks and execves to run unprivileged\n" \
3849 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \
3850 " blacklisting *fork and execve\n" \
3851 " use 'resourcecontrol' to disable process affinity and schedular priority\n",
3852 QEMU_ARCH_ALL)
3853 STEXI
3854 @item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
3855 @findex -sandbox
3856 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3857 disable it. The default is 'off'.
3858 @table @option
3859 @item obsolete=@var{string}
3860 Enable Obsolete system calls
3861 @item elevateprivileges=@var{string}
3862 Disable set*uid|gid system calls
3863 @item spawn=@var{string}
3864 Disable *fork and execve
3865 @item resourcecontrol=@var{string}
3866 Disable process affinity and schedular priority
3867 @end table
3868 ETEXI
3870 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3871 "-readconfig <file>\n", QEMU_ARCH_ALL)
3872 STEXI
3873 @item -readconfig @var{file}
3874 @findex -readconfig
3875 Read device configuration from @var{file}. This approach is useful when you want to spawn
3876 QEMU process with many command line options but you don't want to exceed the command line
3877 character limit.
3878 ETEXI
3879 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3880 "-writeconfig <file>\n"
3881 " read/write config file\n", QEMU_ARCH_ALL)
3882 STEXI
3883 @item -writeconfig @var{file}
3884 @findex -writeconfig
3885 Write device configuration to @var{file}. The @var{file} can be either filename to save
3886 command line and device configuration into file or dash @code{-}) character to print the
3887 output to stdout. This can be later used as input file for @code{-readconfig} option.
3888 ETEXI
3889 HXCOMM Deprecated, same as -no-user-config
3890 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
3891 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3892 "-no-user-config\n"
3893 " do not load default user-provided config files at startup\n",
3894 QEMU_ARCH_ALL)
3895 STEXI
3896 @item -no-user-config
3897 @findex -no-user-config
3898 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3899 config files on @var{sysconfdir}.
3900 ETEXI
3901 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3902 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3903 " specify tracing options\n",
3904 QEMU_ARCH_ALL)
3905 STEXI
3906 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3907 HXCOMM HX does not support conditional compilation of text.
3908 @item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
3909 @findex -trace
3910 @include qemu-option-trace.texi
3911 ETEXI
3913 HXCOMM Internal use
3914 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3915 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3917 #ifdef __linux__
3918 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3919 "-enable-fips enable FIPS 140-2 compliance\n",
3920 QEMU_ARCH_ALL)
3921 #endif
3922 STEXI
3923 @item -enable-fips
3924 @findex -enable-fips
3925 Enable FIPS 140-2 compliance mode.
3926 ETEXI
3928 HXCOMM Deprecated by -machine accel=tcg property
3929 DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3931 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3932 "-msg timestamp[=on|off]\n"
3933 " change the format of messages\n"
3934 " on|off controls leading timestamps (default:on)\n",
3935 QEMU_ARCH_ALL)
3936 STEXI
3937 @item -msg timestamp[=on|off]
3938 @findex -msg
3939 prepend a timestamp to each log message.(default:on)
3940 ETEXI
3942 DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3943 "-dump-vmstate <file>\n"
3944 " Output vmstate information in JSON format to file.\n"
3945 " Use the scripts/vmstate-static-checker.py file to\n"
3946 " check for possible regressions in migration code\n"
3947 " by comparing two such vmstate dumps.\n",
3948 QEMU_ARCH_ALL)
3949 STEXI
3950 @item -dump-vmstate @var{file}
3951 @findex -dump-vmstate
3952 Dump json-encoded vmstate information for current machine type to file
3953 in @var{file}
3954 ETEXI
3956 STEXI
3957 @end table
3958 ETEXI
3959 DEFHEADING()
3961 DEFHEADING(Generic object creation:)
3962 STEXI
3963 @table @option
3964 ETEXI
3966 DEF("object", HAS_ARG, QEMU_OPTION_object,
3967 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3968 " create a new object of type TYPENAME setting properties\n"
3969 " in the order they are specified. Note that the 'id'\n"
3970 " property must be set. These objects are placed in the\n"
3971 " '/objects' path.\n",
3972 QEMU_ARCH_ALL)
3973 STEXI
3974 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3975 @findex -object
3976 Create a new object of type @var{typename} setting properties
3977 in the order they are specified. Note that the 'id'
3978 property must be set. These objects are placed in the
3979 '/objects' path.
3981 @table @option
3983 @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}
3985 Creates a memory file backend object, which can be used to back
3986 the guest RAM with huge pages.
3988 The @option{id} parameter is a unique ID that will be used to reference this
3989 memory region when configuring the @option{-numa} argument.
3991 The @option{size} option provides the size of the memory region, and accepts
3992 common suffixes, eg @option{500M}.
3994 The @option{mem-path} provides the path to either a shared memory or huge page
3995 filesystem mount.
3997 The @option{share} boolean option determines whether the memory
3998 region is marked as private to QEMU, or shared. The latter allows
3999 a co-operating external process to access the QEMU memory region.
4001 The @option{share} is also required for pvrdma devices due to
4002 limitations in the RDMA API provided by Linux.
4004 Setting share=on might affect the ability to configure NUMA
4005 bindings for the memory backend under some circumstances, see
4006 Documentation/vm/numa_memory_policy.txt on the Linux kernel
4007 source tree for additional details.
4009 Setting the @option{discard-data} boolean option to @var{on}
4010 indicates that file contents can be destroyed when QEMU exits,
4011 to avoid unnecessarily flushing data to the backing file. Note
4012 that @option{discard-data} is only an optimization, and QEMU
4013 might not discard file contents if it aborts unexpectedly or is
4014 terminated using SIGKILL.
4016 The @option{merge} boolean option enables memory merge, also known as
4017 MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for
4018 memory deduplication.
4020 Setting the @option{dump} boolean option to @var{off} excludes the memory from
4021 core dumps. This feature is also known as MADV_DONTDUMP.
4023 The @option{prealloc} boolean option enables memory preallocation.
4025 The @option{host-nodes} option binds the memory range to a list of NUMA host
4026 nodes.
4028 The @option{policy} option sets the NUMA policy to one of the following values:
4030 @table @option
4031 @item @var{default}
4032 default host policy
4034 @item @var{preferred}
4035 prefer the given host node list for allocation
4037 @item @var{bind}
4038 restrict memory allocation to the given host node list
4040 @item @var{interleave}
4041 interleave memory allocations across the given host node list
4042 @end table
4044 The @option{align} option specifies the base address alignment when
4045 QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg
4046 @option{2M}. Some backend store specified by @option{mem-path}
4047 requires an alignment different than the default one used by QEMU, eg
4048 the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In
4049 such cases, users can specify the required alignment via this option.
4051 The @option{pmem} option specifies whether the backing file specified
4052 by @option{mem-path} is in host persistent memory that can be accessed
4053 using the SNIA NVM programming model (e.g. Intel NVDIMM).
4054 If @option{pmem} is set to 'on', QEMU will take necessary operations to
4055 guarantee the persistence of its own writes to @option{mem-path}
4056 (e.g. in vNVDIMM label emulation and live migration).
4058 @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}
4060 Creates a memory backend object, which can be used to back the guest RAM.
4061 Memory backend objects offer more control than the @option{-m} option that is
4062 traditionally used to define guest RAM. Please refer to
4063 @option{memory-backend-file} for a description of the options.
4065 @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}
4067 Creates an anonymous memory file backend object, which allows QEMU to
4068 share the memory with an external process (e.g. when using
4069 vhost-user). The memory is allocated with memfd and optional
4070 sealing. (Linux only)
4072 The @option{seal} option creates a sealed-file, that will block
4073 further resizing the memory ('on' by default).
4075 The @option{hugetlb} option specify the file to be created resides in
4076 the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with
4077 the @option{hugetlb} option, the @option{hugetlbsize} option specify
4078 the hugetlb page size on systems that support multiple hugetlb page
4079 sizes (it must be a power of 2 value supported by the system).
4081 In some versions of Linux, the @option{hugetlb} option is incompatible
4082 with the @option{seal} option (requires at least Linux 4.16).
4084 Please refer to @option{memory-backend-file} for a description of the
4085 other options.
4087 @item -object rng-random,id=@var{id},filename=@var{/dev/random}
4089 Creates a random number generator backend which obtains entropy from
4090 a device on the host. The @option{id} parameter is a unique ID that
4091 will be used to reference this entropy backend from the @option{virtio-rng}
4092 device. The @option{filename} parameter specifies which file to obtain
4093 entropy from and if omitted defaults to @option{/dev/random}.
4095 @item -object rng-egd,id=@var{id},chardev=@var{chardevid}
4097 Creates a random number generator backend which obtains entropy from
4098 an external daemon running on the host. The @option{id} parameter is
4099 a unique ID that will be used to reference this entropy backend from
4100 the @option{virtio-rng} device. The @option{chardev} parameter is
4101 the unique ID of a character device backend that provides the connection
4102 to the RNG daemon.
4104 @item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
4106 Creates a TLS anonymous credentials object, which can be used to provide
4107 TLS support on network backends. The @option{id} parameter is a unique
4108 ID which network backends will use to access the credentials. The
4109 @option{endpoint} is either @option{server} or @option{client} depending
4110 on whether the QEMU network backend that uses the credentials will be
4111 acting as a client or as a server. If @option{verify-peer} is enabled
4112 (the default) then once the handshake is completed, the peer credentials
4113 will be verified, though this is a no-op for anonymous credentials.
4115 The @var{dir} parameter tells QEMU where to find the credential
4116 files. For server endpoints, this directory may contain a file
4117 @var{dh-params.pem} providing diffie-hellman parameters to use
4118 for the TLS server. If the file is missing, QEMU will generate
4119 a set of DH parameters at startup. This is a computationally
4120 expensive operation that consumes random pool entropy, so it is
4121 recommended that a persistent set of parameters be generated
4122 upfront and saved.
4124 @item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}]
4126 Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide
4127 TLS support on network backends. The @option{id} parameter is a unique
4128 ID which network backends will use to access the credentials. The
4129 @option{endpoint} is either @option{server} or @option{client} depending
4130 on whether the QEMU network backend that uses the credentials will be
4131 acting as a client or as a server. For clients only, @option{username}
4132 is the username which will be sent to the server. If omitted
4133 it defaults to ``qemu''.
4135 The @var{dir} parameter tells QEMU where to find the keys file.
4136 It is called ``@var{dir}/keys.psk'' and contains ``username:key''
4137 pairs. This file can most easily be created using the GnuTLS
4138 @code{psktool} program.
4140 For server endpoints, @var{dir} may also contain a file
4141 @var{dh-params.pem} providing diffie-hellman parameters to use
4142 for the TLS server. If the file is missing, QEMU will generate
4143 a set of DH parameters at startup. This is a computationally
4144 expensive operation that consumes random pool entropy, so it is
4145 recommended that a persistent set of parameters be generated
4146 up front and saved.
4148 @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}
4150 Creates a TLS anonymous credentials object, which can be used to provide
4151 TLS support on network backends. The @option{id} parameter is a unique
4152 ID which network backends will use to access the credentials. The
4153 @option{endpoint} is either @option{server} or @option{client} depending
4154 on whether the QEMU network backend that uses the credentials will be
4155 acting as a client or as a server. If @option{verify-peer} is enabled
4156 (the default) then once the handshake is completed, the peer credentials
4157 will be verified. With x509 certificates, this implies that the clients
4158 must be provided with valid client certificates too.
4160 The @var{dir} parameter tells QEMU where to find the credential
4161 files. For server endpoints, this directory may contain a file
4162 @var{dh-params.pem} providing diffie-hellman parameters to use
4163 for the TLS server. If the file is missing, QEMU will generate
4164 a set of DH parameters at startup. This is a computationally
4165 expensive operation that consumes random pool entropy, so it is
4166 recommended that a persistent set of parameters be generated
4167 upfront and saved.
4169 For x509 certificate credentials the directory will contain further files
4170 providing the x509 certificates. The certificates must be stored
4171 in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
4172 @var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
4173 @var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
4175 For the @var{server-key.pem} and @var{client-key.pem} files which
4176 contain sensitive private keys, it is possible to use an encrypted
4177 version by providing the @var{passwordid} parameter. This provides
4178 the ID of a previously created @code{secret} object containing the
4179 password for decryption.
4181 The @var{priority} parameter allows to override the global default
4182 priority used by gnutls. This can be useful if the system administrator
4183 needs to use a weaker set of crypto priorities for QEMU without
4184 potentially forcing the weakness onto all applications. Or conversely
4185 if one wants wants a stronger default for QEMU than for all other
4186 applications, they can do this through this parameter. Its format is
4187 a gnutls priority string as described at
4188 @url{https://gnutls.org/manual/html_node/Priority-Strings.html}.
4190 @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
4192 Interval @var{t} can't be 0, this filter batches the packet delivery: all
4193 packets arriving in a given interval on netdev @var{netdevid} are delayed
4194 until the end of the interval. Interval is in microseconds.
4195 @option{status} is optional that indicate whether the netfilter is
4196 on (enabled) or off (disabled), the default status for netfilter will be 'on'.
4198 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4200 @option{all}: the filter is attached both to the receive and the transmit
4201 queue of the netdev (default).
4203 @option{rx}: the filter is attached to the receive queue of the netdev,
4204 where it will receive packets sent to the netdev.
4206 @option{tx}: the filter is attached to the transmit queue of the netdev,
4207 where it will receive packets sent by the netdev.
4209 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4211 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.
4213 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4215 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4216 @var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
4217 filter-redirector will redirect packet with vnet_hdr_len.
4218 Create a filter-redirector we need to differ outdev id from indev id, id can not
4219 be the same. we can just use indev or outdev, but at least one of indev or outdev
4220 need to be specified.
4222 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4224 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4225 secondary from primary to keep secondary tcp connection,and rewrite
4226 tcp packet to primary from secondary make tcp packet can be handled by
4227 client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4229 usage:
4230 colo secondary:
4231 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4232 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4233 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
4235 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4237 Dump the network traffic on netdev @var{dev} to the file specified by
4238 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4239 The file format is libpcap, so it can be analyzed with tools such as tcpdump
4240 or Wireshark.
4242 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4244 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4245 secondary packet. If the packets are same, we will output primary
4246 packet to outdev@var{chardevid}, else we will notify colo-frame
4247 do checkpoint and send primary packet to outdev@var{chardevid}.
4248 if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4250 we must use it with the help of filter-mirror and filter-redirector.
4252 @example
4254 primary:
4255 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4256 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4257 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4258 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4259 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4260 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4261 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4262 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4263 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4264 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4265 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4266 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4268 secondary:
4269 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4270 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4271 -chardev socket,id=red0,host=3.3.3.3,port=9003
4272 -chardev socket,id=red1,host=3.3.3.3,port=9004
4273 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4274 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4276 @end example
4278 If you want to know the detail of above command line, you can read
4279 the colo-compare git log.
4281 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4283 Creates a cryptodev backend which executes crypto opreation from
4284 the QEMU cipher APIS. The @var{id} parameter is
4285 a unique ID that will be used to reference this cryptodev backend from
4286 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4287 which specify the queue number of cryptodev backend, the default of
4288 @var{queues} is 1.
4290 @example
4292 # qemu-system-x86_64 \
4293 [...] \
4294 -object cryptodev-backend-builtin,id=cryptodev0 \
4295 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4296 [...]
4297 @end example
4299 @item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}]
4301 Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}.
4302 The @var{id} parameter is a unique ID that will be used to reference this
4303 cryptodev backend from the @option{virtio-crypto} device.
4304 The chardev should be a unix domain socket backed one. The vhost-user uses
4305 a specifically defined protocol to pass vhost ioctl replacement messages
4306 to an application on the other end of the socket.
4307 The @var{queues} parameter is optional, which specify the queue number
4308 of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1.
4310 @example
4312 # qemu-system-x86_64 \
4313 [...] \
4314 -chardev socket,id=chardev0,path=/path/to/socket \
4315 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \
4316 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4317 [...]
4318 @end example
4320 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4321 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4323 Defines a secret to store a password, encryption key, or some other sensitive
4324 data. The sensitive data can either be passed directly via the @var{data}
4325 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4326 parameter is insecure unless the sensitive data is encrypted.
4328 The sensitive data can be provided in raw format (the default), or base64.
4329 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4330 so base64 is recommended for sending binary data. QEMU will convert from
4331 which ever format is provided to the format it needs internally. eg, an
4332 RBD password can be provided in raw format, even though it will be base64
4333 encoded when passed onto the RBD sever.
4335 For added protection, it is possible to encrypt the data associated with
4336 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4337 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4338 parameter provides the ID of a previously defined secret that contains
4339 the AES-256 decryption key. This key should be 32-bytes long and be
4340 base64 encoded. The @var{iv} parameter provides the random initialization
4341 vector used for encryption of this particular secret and should be a
4342 base64 encrypted string of the 16-byte IV.
4344 The simplest (insecure) usage is to provide the secret inline
4346 @example
4348 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4350 @end example
4352 The simplest secure usage is to provide the secret via a file
4354 # printf "letmein" > mypasswd.txt
4355 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4357 For greater security, AES-256-CBC should be used. To illustrate usage,
4358 consider the openssl command line tool which can encrypt the data. Note
4359 that when encrypting, the plaintext must be padded to the cipher block
4360 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4362 First a master key needs to be created in base64 encoding:
4364 @example
4365 # openssl rand -base64 32 > key.b64
4366 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
4367 @end example
4369 Each secret to be encrypted needs to have a random initialization vector
4370 generated. These do not need to be kept secret
4372 @example
4373 # openssl rand -base64 16 > iv.b64
4374 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
4375 @end example
4377 The secret to be defined can now be encrypted, in this case we're
4378 telling openssl to base64 encode the result, but it could be left
4379 as raw bytes if desired.
4381 @example
4382 # SECRET=$(printf "letmein" |
4383 openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4384 @end example
4386 When launching QEMU, create a master secret pointing to @code{key.b64}
4387 and specify that to be used to decrypt the user password. Pass the
4388 contents of @code{iv.b64} to the second secret
4390 @example
4391 # $QEMU \
4392 -object secret,id=secmaster0,format=base64,file=key.b64 \
4393 -object secret,id=sec0,keyid=secmaster0,format=base64,\
4394 data=$SECRET,iv=$(<iv.b64)
4395 @end example
4397 @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}]
4399 Create a Secure Encrypted Virtualization (SEV) guest object, which can be used
4400 to provide the guest memory encryption support on AMD processors.
4402 When memory encryption is enabled, one of the physical address bit (aka the
4403 C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos}
4404 is used to provide the C-bit position. The C-bit position is Host family dependent
4405 hence user must provide this value. On EPYC, the value should be 47.
4407 When memory encryption is enabled, we loose certain bits in physical address space.
4408 The @option{reduced-phys-bits} is used to provide the number of bits we loose in
4409 physical address space. Similar to C-bit, the value is Host family dependent.
4410 On EPYC, the value should be 5.
4412 The @option{sev-device} provides the device file to use for communicating with
4413 the SEV firmware running inside AMD Secure Processor. The default device is
4414 '/dev/sev'. If hardware supports memory encryption then /dev/sev devices are
4415 created by CCP driver.
4417 The @option{policy} provides the guest policy to be enforced by the SEV firmware
4418 and restrict what configuration and operational commands can be performed on this
4419 guest by the hypervisor. The policy should be provided by the guest owner and is
4420 bound to the guest and cannot be changed throughout the lifetime of the guest.
4421 The default is 0.
4423 If guest @option{policy} allows sharing the key with another SEV guest then
4424 @option{handle} can be use to provide handle of the guest from which to share
4425 the key.
4427 The @option{dh-cert-file} and @option{session-file} provides the guest owner's
4428 Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters
4429 are used for establishing a cryptographic session with the guest owner to
4430 negotiate keys used for attestation. The file must be encoded in base64.
4432 e.g to launch a SEV guest
4433 @example
4434 # $QEMU \
4435 ......
4436 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \
4437 -machine ...,memory-encryption=sev0
4438 .....
4440 @end example
4441 @end table
4443 ETEXI
4446 HXCOMM This is the last statement. Insert new options before this line!
4447 STEXI
4448 @end table
4449 ETEXI