xref: /openbmc/qemu/qemu-options.hx (revision 1ef8185a)
1HXCOMM Use DEFHEADING() to define headings in both help text and texi
2HXCOMM Text between STEXI and ETEXI are copied to texi version and
3HXCOMM discarded from C version
4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
5HXCOMM construct option structures, enums and help message for specified
6HXCOMM architectures.
7HXCOMM HXCOMM can be used for comments, discarded from both texi and C
8
9DEFHEADING(Standard options:)
10STEXI
11@table @option
12ETEXI
13
14DEF("help", 0, QEMU_OPTION_h,
15    "-h or -help     display this help and exit\n", QEMU_ARCH_ALL)
16STEXI
17@item -h
18@findex -h
19Display help and exit
20ETEXI
21
22DEF("version", 0, QEMU_OPTION_version,
23    "-version        display version information and exit\n", QEMU_ARCH_ALL)
24STEXI
25@item -version
26@findex -version
27Display version information and exit
28ETEXI
29
30DEF("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 or tcg (default: tcg)\n"
35    "                kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n"
36    "                vmport=on|off|auto controls emulation of vmport (default: auto)\n"
37    "                kvm_shadow_mem=size of KVM shadow MMU in bytes\n"
38    "                dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
39    "                mem-merge=on|off controls memory merge support (default: on)\n"
40    "                igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
41    "                aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
42    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
43    "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
44    "                nvdimm=on|off controls NVDIMM support (default=off)\n"
45    "                enforce-config-section=on|off enforce configuration section migration (default=off)\n"
46    "                s390-squash-mcss=on|off (deprecated) controls support for squashing into default css (default=off)\n",
47    QEMU_ARCH_ALL)
48STEXI
49@item -machine [type=]@var{name}[,prop=@var{value}[,...]]
50@findex -machine
51Select the emulated machine by @var{name}. Use @code{-machine help} to list
52available machines.
53
54For architectures which aim to support live migration compatibility
55across releases, each release will introduce a new versioned machine
56type. 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.
58
59To allow live migration of guests from QEMU version 2.8.0, to QEMU
60version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8''
61and ``pc-q35-2.8'' machines too. To allow users live migrating VMs
62to skip multiple intermediate releases when upgrading, new releases
63of QEMU will support machine types from many previous versions.
64
65Supported machine properties are:
66@table @option
67@item accel=@var{accels1}[:@var{accels2}[:...]]
68This is used to enable an accelerator. Depending on the target architecture,
69kvm, xen, hax, hvf or tcg can be available. By default, tcg is used. If there is
70more than one accelerator specified, the next one is used if the previous one
71fails to initialize.
72@item kernel_irqchip=on|off
73Controls in-kernel irqchip support for the chosen accelerator when available.
74@item gfx_passthru=on|off
75Enables IGD GFX passthrough support for the chosen machine when available.
76@item vmport=on|off|auto
77Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the
78value based on accel. For accel=xen the default is off otherwise the default
79is on.
80@item kvm_shadow_mem=size
81Defines the size of the KVM shadow MMU.
82@item dump-guest-core=on|off
83Include guest memory in a core dump. The default is on.
84@item mem-merge=on|off
85Enables or disables memory merge support. This feature, when supported by
86the host, de-duplicates identical memory pages among VMs instances
87(enabled by default).
88@item aes-key-wrap=on|off
89Enables or disables AES key wrapping support on s390-ccw hosts. This feature
90controls whether AES wrapping keys will be created to allow
91execution of AES cryptographic functions.  The default is on.
92@item dea-key-wrap=on|off
93Enables or disables DEA key wrapping support on s390-ccw hosts. This feature
94controls whether DEA wrapping keys will be created to allow
95execution of DEA cryptographic functions.  The default is on.
96@item nvdimm=on|off
97Enables or disables NVDIMM support. The default is off.
98@item s390-squash-mcss=on|off
99Enables or disables squashing subchannels into the default css.
100The default is off.
101NOTE: This property is deprecated and will be removed in future releases.
102The ``s390-squash-mcss=on`` property has been obsoleted by allowing the
103cssid to be chosen freely. Instead of squashing subchannels into the
104default channel subsystem image for guests that do not support multiple
105channel subsystems, all devices can be put into the default channel
106subsystem image.
107@item enforce-config-section=on|off
108If @option{enforce-config-section} is set to @var{on}, force migration
109code to send configuration section even if the machine-type sets the
110@option{migration.send-configuration} property to @var{off}.
111NOTE: this parameter is deprecated. Please use @option{-global}
112@option{migration.send-configuration}=@var{on|off} instead.
113@end table
114ETEXI
115
116HXCOMM Deprecated by -machine
117DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
118
119DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
120    "-cpu cpu        select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
121STEXI
122@item -cpu @var{model}
123@findex -cpu
124Select CPU model (@code{-cpu help} for list and additional feature selection)
125ETEXI
126
127DEF("accel", HAS_ARG, QEMU_OPTION_accel,
128    "-accel [accel=]accelerator[,thread=single|multi]\n"
129    "                select accelerator (kvm, xen, hax, hvf or tcg; use 'help' for a list)\n"
130    "                thread=single|multi (enable multi-threaded TCG)", QEMU_ARCH_ALL)
131STEXI
132@item -accel @var{name}[,prop=@var{value}[,...]]
133@findex -accel
134This is used to enable an accelerator. Depending on the target architecture,
135kvm, xen, hax, hvf or tcg can be available. By default, tcg is used. If there is
136more than one accelerator specified, the next one is used if the previous one
137fails to initialize.
138@table @option
139@item thread=single|multi
140Controls number of TCG threads. When the TCG is multi-threaded there will be one
141thread per vCPU therefor taking advantage of additional host cores. The default
142is to enable multi-threading where both the back-end and front-ends support it and
143no incompatible TCG features have been enabled (e.g. icount/replay).
144@end table
145ETEXI
146
147DEF("smp", HAS_ARG, QEMU_OPTION_smp,
148    "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
149    "                set the number of CPUs to 'n' [default=1]\n"
150    "                maxcpus= maximum number of total cpus, including\n"
151    "                offline CPUs for hotplug, etc\n"
152    "                cores= number of CPU cores on one socket\n"
153    "                threads= number of threads on one CPU core\n"
154    "                sockets= number of discrete sockets in the system\n",
155        QEMU_ARCH_ALL)
156STEXI
157@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
158@findex -smp
159Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
160CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
161to 4.
162For the PC target, the number of @var{cores} per socket, the number
163of @var{threads} per cores and the total number of @var{sockets} can be
164specified. Missing values will be computed. If any on the three values is
165given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
166specifies the maximum number of hotpluggable CPUs.
167ETEXI
168
169DEF("numa", HAS_ARG, QEMU_OPTION_numa,
170    "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
171    "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
172    "-numa dist,src=source,dst=destination,val=distance\n"
173    "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n",
174    QEMU_ARCH_ALL)
175STEXI
176@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
177@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
178@itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance}
179@itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}]
180@findex -numa
181Define a NUMA node and assign RAM and VCPUs to it.
182Set the NUMA distance from a source node to a destination node.
183
184Legacy VCPU assignment uses @samp{cpus} option where
185@var{firstcpu} and @var{lastcpu} are CPU indexes. Each
186@samp{cpus} option represent a contiguous range of CPU indexes
187(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous
188set of VCPUs can be represented by providing multiple @samp{cpus}
189options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically
190split between them.
191
192For example, the following option assigns VCPUs 0, 1, 2 and 5 to
193a NUMA node:
194@example
195-numa node,cpus=0-2,cpus=5
196@end example
197
198@samp{cpu} option is a new alternative to @samp{cpus} option
199which uses @samp{socket-id|core-id|thread-id} properties to assign
200CPU objects to a @var{node} using topology layout properties of CPU.
201The set of properties is machine specific, and depends on used
202machine type/@samp{smp} options. It could be queried with
203@samp{hotpluggable-cpus} monitor command.
204@samp{node-id} property specifies @var{node} to which CPU object
205will be assigned, it's required for @var{node} to be declared
206with @samp{node} option before it's used with @samp{cpu} option.
207
208For example:
209@example
210-M pc \
211-smp 1,sockets=2,maxcpus=2 \
212-numa node,nodeid=0 -numa node,nodeid=1 \
213-numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1
214@end example
215
216@samp{mem} assigns a given RAM amount to a node. @samp{memdev}
217assigns RAM from a given memory backend device to a node. If
218@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is
219split equally between them.
220
221@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore,
222if one node uses @samp{memdev}, all of them have to use it.
223
224@var{source} and @var{destination} are NUMA node IDs.
225@var{distance} is the NUMA distance from @var{source} to @var{destination}.
226The distance from a node to itself is always 10. If any pair of nodes is
227given a distance, then all pairs must be given distances. Although, when
228distances are only given in one direction for each pair of nodes, then
229the distances in the opposite directions are assumed to be the same. If,
230however, an asymmetrical pair of distances is given for even one node
231pair, then all node pairs must be provided distance values for both
232directions, even when they are symmetrical. When a node is unreachable
233from another node, set the pair's distance to 255.
234
235Note that the -@option{numa} option doesn't allocate any of the
236specified resources, it just assigns existing resources to NUMA
237nodes. This means that one still has to use the @option{-m},
238@option{-smp} options to allocate RAM and VCPUs respectively.
239
240ETEXI
241
242DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
243    "-add-fd fd=fd,set=set[,opaque=opaque]\n"
244    "                Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
245STEXI
246@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
247@findex -add-fd
248
249Add a file descriptor to an fd set.  Valid options are:
250
251@table @option
252@item fd=@var{fd}
253This option defines the file descriptor of which a duplicate is added to fd set.
254The file descriptor cannot be stdin, stdout, or stderr.
255@item set=@var{set}
256This option defines the ID of the fd set to add the file descriptor to.
257@item opaque=@var{opaque}
258This option defines a free-form string that can be used to describe @var{fd}.
259@end table
260
261You can open an image using pre-opened file descriptors from an fd set:
262@example
263qemu-system-i386
264-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
265-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
266-drive file=/dev/fdset/2,index=0,media=disk
267@end example
268ETEXI
269
270DEF("set", HAS_ARG, QEMU_OPTION_set,
271    "-set group.id.arg=value\n"
272    "                set <arg> parameter for item <id> of type <group>\n"
273    "                i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
274STEXI
275@item -set @var{group}.@var{id}.@var{arg}=@var{value}
276@findex -set
277Set parameter @var{arg} for item @var{id} of type @var{group}
278ETEXI
279
280DEF("global", HAS_ARG, QEMU_OPTION_global,
281    "-global driver.property=value\n"
282    "-global driver=driver,property=property,value=value\n"
283    "                set a global default for a driver property\n",
284    QEMU_ARCH_ALL)
285STEXI
286@item -global @var{driver}.@var{prop}=@var{value}
287@itemx -global driver=@var{driver},property=@var{property},value=@var{value}
288@findex -global
289Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
290
291@example
292qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img
293@end example
294
295In particular, you can use this to set driver properties for devices which are
296created automatically by the machine model. To create a device which is not
297created automatically and set properties on it, use -@option{device}.
298
299-global @var{driver}.@var{prop}=@var{value} is shorthand for -global
300driver=@var{driver},property=@var{prop},value=@var{value}.  The
301longhand syntax works even when @var{driver} contains a dot.
302ETEXI
303
304DEF("boot", HAS_ARG, QEMU_OPTION_boot,
305    "-boot [order=drives][,once=drives][,menu=on|off]\n"
306    "      [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
307    "                'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
308    "                'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
309    "                'sp_time': the period that splash picture last if menu=on, unit is ms\n"
310    "                'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
311    QEMU_ARCH_ALL)
312STEXI
313@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]
314@findex -boot
315Specify boot order @var{drives} as a string of drive letters. Valid
316drive letters depend on the target architecture. The x86 PC uses: a, b
317(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
318from network adapter 1-4), hard disk boot is the default. To apply a
319particular boot order only on the first startup, specify it via
320@option{once}. Note that the @option{order} or @option{once} parameter
321should not be used together with the @option{bootindex} property of
322devices, since the firmware implementations normally do not support both
323at the same time.
324
325Interactive boot menus/prompts can be enabled via @option{menu=on} as far
326as firmware/BIOS supports them. The default is non-interactive boot.
327
328A splash picture could be passed to bios, enabling user to show it as logo,
329when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
330supports them. Currently Seabios for X86 system support it.
331limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
332format(true color). The resolution should be supported by the SVGA mode, so
333the recommended is 320x240, 640x480, 800x640.
334
335A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
336when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
337reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
338system support it.
339
340Do strict boot via @option{strict=on} as far as firmware/BIOS
341supports it. This only effects when boot priority is changed by
342bootindex options. The default is non-strict boot.
343
344@example
345# try to boot from network first, then from hard disk
346qemu-system-i386 -boot order=nc
347# boot from CD-ROM first, switch back to default order after reboot
348qemu-system-i386 -boot once=d
349# boot with a splash picture for 5 seconds.
350qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
351@end example
352
353Note: The legacy format '-boot @var{drives}' is still supported but its
354use is discouraged as it may be removed from future versions.
355ETEXI
356
357DEF("m", HAS_ARG, QEMU_OPTION_m,
358    "-m [size=]megs[,slots=n,maxmem=size]\n"
359    "                configure guest RAM\n"
360    "                size: initial amount of guest memory\n"
361    "                slots: number of hotplug slots (default: none)\n"
362    "                maxmem: maximum amount of guest memory (default: none)\n"
363    "NOTE: Some architectures might enforce a specific granularity\n",
364    QEMU_ARCH_ALL)
365STEXI
366@item -m [size=]@var{megs}[,slots=n,maxmem=size]
367@findex -m
368Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
369Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
370megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
371could be used to set amount of hotpluggable memory slots and maximum amount of
372memory. Note that @var{maxmem} must be aligned to the page size.
373
374For example, the following command-line sets the guest startup RAM size to
3751GB, creates 3 slots to hotplug additional memory and sets the maximum
376memory the guest can reach to 4GB:
377
378@example
379qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
380@end example
381
382If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
383be enabled and the guest startup RAM will never increase.
384ETEXI
385
386DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
387    "-mem-path FILE  provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
388STEXI
389@item -mem-path @var{path}
390@findex -mem-path
391Allocate guest RAM from a temporarily created file in @var{path}.
392ETEXI
393
394DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
395    "-mem-prealloc   preallocate guest memory (use with -mem-path)\n",
396    QEMU_ARCH_ALL)
397STEXI
398@item -mem-prealloc
399@findex -mem-prealloc
400Preallocate memory when using -mem-path.
401ETEXI
402
403DEF("k", HAS_ARG, QEMU_OPTION_k,
404    "-k language     use keyboard layout (for example 'fr' for French)\n",
405    QEMU_ARCH_ALL)
406STEXI
407@item -k @var{language}
408@findex -k
409Use keyboard layout @var{language} (for example @code{fr} for
410French). This option is only needed where it is not easy to get raw PC
411keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
412display). You don't normally need to use it on PC/Linux or PC/Windows
413hosts.
414
415The available layouts are:
416@example
417ar  de-ch  es  fo     fr-ca  hu  ja  mk     no  pt-br  sv
418da  en-gb  et  fr     fr-ch  is  lt  nl     pl  ru     th
419de  en-us  fi  fr-be  hr     it  lv  nl-be  pt  sl     tr
420@end example
421
422The default is @code{en-us}.
423ETEXI
424
425
426DEF("audio-help", 0, QEMU_OPTION_audio_help,
427    "-audio-help     print list of audio drivers and their options\n",
428    QEMU_ARCH_ALL)
429STEXI
430@item -audio-help
431@findex -audio-help
432Will show the audio subsystem help: list of drivers, tunable
433parameters.
434ETEXI
435
436DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
437    "-soundhw c1,... enable audio support\n"
438    "                and only specified sound cards (comma separated list)\n"
439    "                use '-soundhw help' to get the list of supported cards\n"
440    "                use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
441STEXI
442@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
443@findex -soundhw
444Enable audio and selected sound hardware. Use 'help' to print all
445available sound hardware.
446
447@example
448qemu-system-i386 -soundhw sb16,adlib disk.img
449qemu-system-i386 -soundhw es1370 disk.img
450qemu-system-i386 -soundhw ac97 disk.img
451qemu-system-i386 -soundhw hda disk.img
452qemu-system-i386 -soundhw all disk.img
453qemu-system-i386 -soundhw help
454@end example
455
456Note that Linux's i810_audio OSS kernel (for AC97) module might
457require manually specifying clocking.
458
459@example
460modprobe i810_audio clocking=48000
461@end example
462ETEXI
463
464DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
465    "-balloon none   disable balloon device\n"
466    "-balloon virtio[,addr=str]\n"
467    "                enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
468STEXI
469@item -balloon none
470@findex -balloon
471Disable balloon device.
472@item -balloon virtio[,addr=@var{addr}]
473Enable virtio balloon device (default), optionally with PCI address
474@var{addr}.
475ETEXI
476
477DEF("device", HAS_ARG, QEMU_OPTION_device,
478    "-device driver[,prop[=value][,...]]\n"
479    "                add device (based on driver)\n"
480    "                prop=value,... sets driver properties\n"
481    "                use '-device help' to print all possible drivers\n"
482    "                use '-device driver,help' to print all possible properties\n",
483    QEMU_ARCH_ALL)
484STEXI
485@item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
486@findex -device
487Add device @var{driver}.  @var{prop}=@var{value} sets driver
488properties.  Valid properties depend on the driver.  To get help on
489possible drivers and properties, use @code{-device help} and
490@code{-device @var{driver},help}.
491
492Some drivers are:
493@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}]
494
495Add an IPMI BMC.  This is a simulation of a hardware management
496interface processor that normally sits on a system.  It provides
497a watchdog and the ability to reset and power control the system.
498You need to connect this to an IPMI interface to make it useful
499
500The IPMI slave address to use for the BMC.  The default is 0x20.
501This address is the BMC's address on the I2C network of management
502controllers.  If you don't know what this means, it is safe to ignore
503it.
504
505@table @option
506@item bmc=@var{id}
507The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
508@item slave_addr=@var{val}
509Define slave address to use for the BMC.  The default is 0x20.
510@item sdrfile=@var{file}
511file containing raw Sensor Data Records (SDR) data. The default is none.
512@item fruareasize=@var{val}
513size of a Field Replaceable Unit (FRU) area.  The default is 1024.
514@item frudatafile=@var{file}
515file containing raw Field Replaceable Unit (FRU) inventory data. The default is none.
516@end table
517
518@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
519
520Add a connection to an external IPMI BMC simulator.  Instead of
521locally emulating the BMC like the above item, instead connect
522to an external entity that provides the IPMI services.
523
524A connection is made to an external BMC simulator.  If you do this, it
525is strongly recommended that you use the "reconnect=" chardev option
526to reconnect to the simulator if the connection is lost.  Note that if
527this is not used carefully, it can be a security issue, as the
528interface has the ability to send resets, NMIs, and power off the VM.
529It's best if QEMU makes a connection to an external simulator running
530on a secure port on localhost, so neither the simulator nor QEMU is
531exposed to any outside network.
532
533See the "lanserv/README.vm" file in the OpenIPMI library for more
534details on the external interface.
535
536@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
537
538Add a KCS IPMI interafce on the ISA bus.  This also adds a
539corresponding ACPI and SMBIOS entries, if appropriate.
540
541@table @option
542@item bmc=@var{id}
543The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
544@item ioport=@var{val}
545Define the I/O address of the interface.  The default is 0xca0 for KCS.
546@item irq=@var{val}
547Define the interrupt to use.  The default is 5.  To disable interrupts,
548set this to 0.
549@end table
550
551@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
552
553Like the KCS interface, but defines a BT interface.  The default port is
5540xe4 and the default interrupt is 5.
555
556ETEXI
557
558DEF("name", HAS_ARG, QEMU_OPTION_name,
559    "-name string1[,process=string2][,debug-threads=on|off]\n"
560    "                set the name of the guest\n"
561    "                string1 sets the window title and string2 the process name (on Linux)\n"
562    "                When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
563    "                NOTE: The thread names are for debugging and not a stable API.\n",
564    QEMU_ARCH_ALL)
565STEXI
566@item -name @var{name}
567@findex -name
568Sets the @var{name} of the guest.
569This name will be displayed in the SDL window caption.
570The @var{name} will also be used for the VNC server.
571Also optionally set the top visible process name in Linux.
572Naming of individual threads can also be enabled on Linux to aid debugging.
573ETEXI
574
575DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
576    "-uuid %08x-%04x-%04x-%04x-%012x\n"
577    "                specify machine UUID\n", QEMU_ARCH_ALL)
578STEXI
579@item -uuid @var{uuid}
580@findex -uuid
581Set system UUID.
582ETEXI
583
584STEXI
585@end table
586ETEXI
587DEFHEADING()
588
589DEFHEADING(Block device options:)
590STEXI
591@table @option
592ETEXI
593
594DEF("fda", HAS_ARG, QEMU_OPTION_fda,
595    "-fda/-fdb file  use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
596DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
597STEXI
598@item -fda @var{file}
599@itemx -fdb @var{file}
600@findex -fda
601@findex -fdb
602Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
603ETEXI
604
605DEF("hda", HAS_ARG, QEMU_OPTION_hda,
606    "-hda/-hdb file  use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
607DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
608DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
609    "-hdc/-hdd file  use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
610DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
611STEXI
612@item -hda @var{file}
613@itemx -hdb @var{file}
614@itemx -hdc @var{file}
615@itemx -hdd @var{file}
616@findex -hda
617@findex -hdb
618@findex -hdc
619@findex -hdd
620Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
621ETEXI
622
623DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
624    "-cdrom file     use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
625    QEMU_ARCH_ALL)
626STEXI
627@item -cdrom @var{file}
628@findex -cdrom
629Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
630@option{-cdrom} at the same time). You can use the host CD-ROM by
631using @file{/dev/cdrom} as filename (@pxref{host_drives}).
632ETEXI
633
634DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev,
635    "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n"
636    "          [,cache.direct=on|off][,cache.no-flush=on|off]\n"
637    "          [,read-only=on|off][,detect-zeroes=on|off|unmap]\n"
638    "          [,driver specific parameters...]\n"
639    "                configure a block backend\n", QEMU_ARCH_ALL)
640STEXI
641@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]]
642@findex -blockdev
643
644Define a new block driver node. Some of the options apply to all block drivers,
645other options are only accepted for a specific block driver. See below for a
646list of generic options and options for the most common block drivers.
647
648Options that expect a reference to another node (e.g. @code{file}) can be
649given in two ways. Either you specify the node name of an already existing node
650(file=@var{node-name}), or you define a new node inline, adding options
651for the referenced node after a dot (file.filename=@var{path},file.aio=native).
652
653A block driver node created with @option{-blockdev} can be used for a guest
654device by specifying its node name for the @code{drive} property in a
655@option{-device} argument that defines a block device.
656
657@table @option
658@item Valid options for any block driver node:
659
660@table @code
661@item driver
662Specifies the block driver to use for the given node.
663@item node-name
664This defines the name of the block driver node by which it will be referenced
665later. The name must be unique, i.e. it must not match the name of a different
666block driver node, or (if you use @option{-drive} as well) the ID of a drive.
667
668If no node name is specified, it is automatically generated. The generated node
669name is not intended to be predictable and changes between QEMU invocations.
670For the top level, an explicit node name must be specified.
671@item read-only
672Open the node read-only. Guest write attempts will fail.
673@item cache.direct
674The host page cache can be avoided with @option{cache.direct=on}. This will
675attempt to do disk IO directly to the guest's memory. QEMU may still perform an
676internal copy of the data.
677@item cache.no-flush
678In case you don't care about data integrity over host failures, you can use
679@option{cache.no-flush=on}. This option tells QEMU that it never needs to write
680any data to the disk but can instead keep things in cache. If anything goes
681wrong, like your host losing power, the disk storage getting disconnected
682accidentally, etc. your image will most probably be rendered unusable.
683@item discard=@var{discard}
684@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls
685whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are
686ignored or passed to the filesystem. Some machine types may not support
687discard requests.
688@item detect-zeroes=@var{detect-zeroes}
689@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
690conversion of plain zero writes by the OS to driver specific optimized
691zero write commands. You may even choose "unmap" if @var{discard} is set
692to "unmap" to allow a zero write to be converted to an @code{unmap} operation.
693@end table
694
695@item Driver-specific options for @code{file}
696
697This is the protocol-level block driver for accessing regular files.
698
699@table @code
700@item filename
701The path to the image file in the local filesystem
702@item aio
703Specifies the AIO backend (threads/native, default: threads)
704@item locking
705Specifies whether the image file is protected with Linux OFD / POSIX locks. The
706default is to use the Linux Open File Descriptor API if available, otherwise no
707lock is applied.  (auto/on/off, default: auto)
708@end table
709Example:
710@example
711-blockdev driver=file,node-name=disk,filename=disk.img
712@end example
713
714@item Driver-specific options for @code{raw}
715
716This is the image format block driver for raw images. It is usually
717stacked on top of a protocol level block driver such as @code{file}.
718
719@table @code
720@item file
721Reference to or definition of the data source block driver node
722(e.g. a @code{file} driver node)
723@end table
724Example 1:
725@example
726-blockdev driver=file,node-name=disk_file,filename=disk.img
727-blockdev driver=raw,node-name=disk,file=disk_file
728@end example
729Example 2:
730@example
731-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img
732@end example
733
734@item Driver-specific options for @code{qcow2}
735
736This is the image format block driver for qcow2 images. It is usually
737stacked on top of a protocol level block driver such as @code{file}.
738
739@table @code
740@item file
741Reference to or definition of the data source block driver node
742(e.g. a @code{file} driver node)
743
744@item backing
745Reference to or definition of the backing file block device (default is taken
746from the image file). It is allowed to pass an empty string here in order to
747disable the default backing file.
748
749@item lazy-refcounts
750Whether to enable the lazy refcounts feature (on/off; default is taken from the
751image file)
752
753@item cache-size
754The maximum total size of the L2 table and refcount block caches in bytes
755(default: 1048576 bytes or 8 clusters, whichever is larger)
756
757@item l2-cache-size
758The maximum size of the L2 table cache in bytes
759(default: 4/5 of the total cache size)
760
761@item refcount-cache-size
762The maximum size of the refcount block cache in bytes
763(default: 1/5 of the total cache size)
764
765@item cache-clean-interval
766Clean unused entries in the L2 and refcount caches. The interval is in seconds.
767The default value is 0 and it disables this feature.
768
769@item pass-discard-request
770Whether discard requests to the qcow2 device should be forwarded to the data
771source (on/off; default: on if discard=unmap is specified, off otherwise)
772
773@item pass-discard-snapshot
774Whether discard requests for the data source should be issued when a snapshot
775operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off;
776default: on)
777
778@item pass-discard-other
779Whether discard requests for the data source should be issued on other
780occasions where a cluster gets freed (on/off; default: off)
781
782@item overlap-check
783Which overlap checks to perform for writes to the image
784(none/constant/cached/all; default: cached). For details or finer
785granularity control refer to the QAPI documentation of @code{blockdev-add}.
786@end table
787
788Example 1:
789@example
790-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
791-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216
792@end example
793Example 2:
794@example
795-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2
796@end example
797
798@item Driver-specific options for other drivers
799Please refer to the QAPI documentation of the @code{blockdev-add} QMP command.
800
801@end table
802
803ETEXI
804
805DEF("drive", HAS_ARG, QEMU_OPTION_drive,
806    "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
807    "       [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
808    "       [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
809    "       [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
810    "       [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
811    "       [,readonly=on|off][,copy-on-read=on|off]\n"
812    "       [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
813    "       [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
814    "       [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
815    "       [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
816    "       [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
817    "       [[,iops_size=is]]\n"
818    "       [[,group=g]]\n"
819    "                use 'file' as a drive image\n", QEMU_ARCH_ALL)
820STEXI
821@item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
822@findex -drive
823
824Define a new drive. This includes creating a block driver node (the backend) as
825well as a guest device, and is mostly a shortcut for defining the corresponding
826@option{-blockdev} and @option{-device} options.
827
828@option{-drive} accepts all options that are accepted by @option{-blockdev}. In
829addition, it knows the following options:
830
831@table @option
832@item file=@var{file}
833This option defines which disk image (@pxref{disk_images}) to use with
834this drive. If the filename contains comma, you must double it
835(for instance, "file=my,,file" to use file "my,file").
836
837Special files such as iSCSI devices can be specified using protocol
838specific URLs. See the section for "Device URL Syntax" for more information.
839@item if=@var{interface}
840This option defines on which type on interface the drive is connected.
841Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
842@item bus=@var{bus},unit=@var{unit}
843These options define where is connected the drive by defining the bus number and
844the unit id.
845@item index=@var{index}
846This option defines where is connected the drive by using an index in the list
847of available connectors of a given interface type.
848@item media=@var{media}
849This option defines the type of the media: disk or cdrom.
850@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
851Force disk physical geometry and the optional BIOS translation (trans=none or
852lba). These parameters are deprecated, use the corresponding parameters
853of @code{-device} instead.
854@item snapshot=@var{snapshot}
855@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
856(see @option{-snapshot}).
857@item cache=@var{cache}
858@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough"
859and controls how the host cache is used to access block data. This is a
860shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
861options (as in @option{-blockdev}), and additionally @option{cache.writeback},
862which provides a default for the @option{write-cache} option of block guest
863devices (as in @option{-device}). The modes correspond to the following
864settings:
865
866@c Our texi2pod.pl script doesn't support @multitable, so fall back to using
867@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
868@c and the HTML output.
869@example
870@             │ cache.writeback   cache.direct   cache.no-flush
871─────────────┼─────────────────────────────────────────────────
872writeback    │ on                off            off
873none         │ on                on             off
874writethrough │ off               off            off
875directsync   │ off               on             off
876unsafe       │ on                off            on
877@end example
878
879The default mode is @option{cache=writeback}.
880
881@item aio=@var{aio}
882@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
883@item format=@var{format}
884Specify which disk @var{format} will be used rather than detecting
885the format.  Can be used to specify format=raw to avoid interpreting
886an untrusted format header.
887@item serial=@var{serial}
888This option specifies the serial number to assign to the device. This
889parameter is deprecated, use the corresponding parameter of @code{-device}
890instead.
891@item addr=@var{addr}
892Specify the controller's PCI address (if=virtio only). This parameter is
893deprecated, use the corresponding parameter of @code{-device} instead.
894@item werror=@var{action},rerror=@var{action}
895Specify which @var{action} to take on write and read errors. Valid actions are:
896"ignore" (ignore the error and try to continue), "stop" (pause QEMU),
897"report" (report the error to the guest), "enospc" (pause QEMU only if the
898host disk is full; report the error to the guest otherwise).
899The default setting is @option{werror=enospc} and @option{rerror=report}.
900@item copy-on-read=@var{copy-on-read}
901@var{copy-on-read} is "on" or "off" and enables whether to copy read backing
902file sectors into the image file.
903@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
904Specify bandwidth throttling limits in bytes per second, either for all request
905types or for reads or writes only.  Small values can lead to timeouts or hangs
906inside the guest.  A safe minimum for disks is 2 MB/s.
907@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
908Specify bursts in bytes per second, either for all request types or for reads
909or writes only.  Bursts allow the guest I/O to spike above the limit
910temporarily.
911@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
912Specify request rate limits in requests per second, either for all request
913types or for reads or writes only.
914@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
915Specify bursts in requests per second, either for all request types or for reads
916or writes only.  Bursts allow the guest I/O to spike above the limit
917temporarily.
918@item iops_size=@var{is}
919Let every @var{is} bytes of a request count as a new request for iops
920throttling purposes.  Use this option to prevent guests from circumventing iops
921limits by sending fewer but larger requests.
922@item group=@var{g}
923Join a throttling quota group with given name @var{g}.  All drives that are
924members of the same group are accounted for together.  Use this option to
925prevent guests from circumventing throttling limits by using many small disks
926instead of a single larger disk.
927@end table
928
929By default, the @option{cache.writeback=on} mode is used. It will report data
930writes as completed as soon as the data is present in the host page cache.
931This is safe as long as your guest OS makes sure to correctly flush disk caches
932where needed. If your guest OS does not handle volatile disk write caches
933correctly and your host crashes or loses power, then the guest may experience
934data corruption.
935
936For such guests, you should consider using @option{cache.writeback=off}. This
937means that the host page cache will be used to read and write data, but write
938notification will be sent to the guest only after QEMU has made sure to flush
939each write to the disk. Be aware that this has a major impact on performance.
940
941When using the @option{-snapshot} option, unsafe caching is always used.
942
943Copy-on-read avoids accessing the same backing file sectors repeatedly and is
944useful when the backing file is over a slow network.  By default copy-on-read
945is off.
946
947Instead of @option{-cdrom} you can use:
948@example
949qemu-system-i386 -drive file=file,index=2,media=cdrom
950@end example
951
952Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
953use:
954@example
955qemu-system-i386 -drive file=file,index=0,media=disk
956qemu-system-i386 -drive file=file,index=1,media=disk
957qemu-system-i386 -drive file=file,index=2,media=disk
958qemu-system-i386 -drive file=file,index=3,media=disk
959@end example
960
961You can open an image using pre-opened file descriptors from an fd set:
962@example
963qemu-system-i386
964-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
965-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
966-drive file=/dev/fdset/2,index=0,media=disk
967@end example
968
969You can connect a CDROM to the slave of ide0:
970@example
971qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
972@end example
973
974If you don't specify the "file=" argument, you define an empty drive:
975@example
976qemu-system-i386 -drive if=ide,index=1,media=cdrom
977@end example
978
979Instead of @option{-fda}, @option{-fdb}, you can use:
980@example
981qemu-system-i386 -drive file=file,index=0,if=floppy
982qemu-system-i386 -drive file=file,index=1,if=floppy
983@end example
984
985By default, @var{interface} is "ide" and @var{index} is automatically
986incremented:
987@example
988qemu-system-i386 -drive file=a -drive file=b"
989@end example
990is interpreted like:
991@example
992qemu-system-i386 -hda a -hdb b
993@end example
994ETEXI
995
996DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
997    "-mtdblock file  use 'file' as on-board Flash memory image\n",
998    QEMU_ARCH_ALL)
999STEXI
1000@item -mtdblock @var{file}
1001@findex -mtdblock
1002Use @var{file} as on-board Flash memory image.
1003ETEXI
1004
1005DEF("sd", HAS_ARG, QEMU_OPTION_sd,
1006    "-sd file        use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
1007STEXI
1008@item -sd @var{file}
1009@findex -sd
1010Use @var{file} as SecureDigital card image.
1011ETEXI
1012
1013DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
1014    "-pflash file    use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
1015STEXI
1016@item -pflash @var{file}
1017@findex -pflash
1018Use @var{file} as a parallel flash image.
1019ETEXI
1020
1021DEF("snapshot", 0, QEMU_OPTION_snapshot,
1022    "-snapshot       write to temporary files instead of disk image files\n",
1023    QEMU_ARCH_ALL)
1024STEXI
1025@item -snapshot
1026@findex -snapshot
1027Write to temporary files instead of disk image files. In this case,
1028the raw disk image you use is not written back. You can however force
1029the write back by pressing @key{C-a s} (@pxref{disk_images}).
1030ETEXI
1031
1032DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
1033    "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1034    " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1035    " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1036    " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1037    " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1038    " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1039    " [[,throttling.iops-size=is]]\n",
1040    QEMU_ARCH_ALL)
1041
1042STEXI
1043
1044@item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}]
1045@findex -fsdev
1046Define a new file system device. Valid options are:
1047@table @option
1048@item @var{fsdriver}
1049This option specifies the fs driver backend to use.
1050Currently "local", "handle" and "proxy" file system drivers are supported.
1051@item id=@var{id}
1052Specifies identifier for this device
1053@item path=@var{path}
1054Specifies the export path for the file system device. Files under
1055this path will be available to the 9p client on the guest.
1056@item security_model=@var{security_model}
1057Specifies the security model to be used for this export path.
1058Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1059In "passthrough" security model, files are stored using the same
1060credentials as they are created on the guest. This requires QEMU
1061to run as root. In "mapped-xattr" security model, some of the file
1062attributes like uid, gid, mode bits and link target are stored as
1063file attributes. For "mapped-file" these attributes are stored in the
1064hidden .virtfs_metadata directory. Directories exported by this security model cannot
1065interact with other unix tools. "none" security model is same as
1066passthrough except the sever won't report failures if it fails to
1067set file attributes like ownership. Security model is mandatory
1068only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1069security model as a parameter.
1070@item writeout=@var{writeout}
1071This is an optional argument. The only supported value is "immediate".
1072This means that host page cache will be used to read and write data but
1073write notification will be sent to the guest only when the data has been
1074reported as written by the storage subsystem.
1075@item readonly
1076Enables exporting 9p share as a readonly mount for guests. By default
1077read-write access is given.
1078@item socket=@var{socket}
1079Enables proxy filesystem driver to use passed socket file for communicating
1080with virtfs-proxy-helper
1081@item sock_fd=@var{sock_fd}
1082Enables proxy filesystem driver to use passed socket descriptor for
1083communicating with virtfs-proxy-helper. Usually a helper like libvirt
1084will create socketpair and pass one of the fds as sock_fd
1085@item fmode=@var{fmode}
1086Specifies the default mode for newly created files on the host. Works only
1087with security models "mapped-xattr" and "mapped-file".
1088@item dmode=@var{dmode}
1089Specifies the default mode for newly created directories on the host. Works
1090only with security models "mapped-xattr" and "mapped-file".
1091@end table
1092
1093-fsdev option is used along with -device driver "virtio-9p-pci".
1094@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
1095Options for virtio-9p-pci driver are:
1096@table @option
1097@item fsdev=@var{id}
1098Specifies the id value specified along with -fsdev option
1099@item mount_tag=@var{mount_tag}
1100Specifies the tag name to be used by the guest to mount this export point
1101@end table
1102
1103ETEXI
1104
1105DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
1106    "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1107    "        [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1108    QEMU_ARCH_ALL)
1109
1110STEXI
1111
1112@item -virtfs @var{fsdriver}[,path=@var{path}],mount_tag=@var{mount_tag}[,security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}]
1113@findex -virtfs
1114
1115The general form of a Virtual File system pass-through options are:
1116@table @option
1117@item @var{fsdriver}
1118This option specifies the fs driver backend to use.
1119Currently "local", "handle" and "proxy" file system drivers are supported.
1120@item id=@var{id}
1121Specifies identifier for this device
1122@item path=@var{path}
1123Specifies the export path for the file system device. Files under
1124this path will be available to the 9p client on the guest.
1125@item security_model=@var{security_model}
1126Specifies the security model to be used for this export path.
1127Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1128In "passthrough" security model, files are stored using the same
1129credentials as they are created on the guest. This requires QEMU
1130to run as root. In "mapped-xattr" security model, some of the file
1131attributes like uid, gid, mode bits and link target are stored as
1132file attributes. For "mapped-file" these attributes are stored in the
1133hidden .virtfs_metadata directory. Directories exported by this security model cannot
1134interact with other unix tools. "none" security model is same as
1135passthrough except the sever won't report failures if it fails to
1136set file attributes like ownership. Security model is mandatory only
1137for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1138model as a parameter.
1139@item writeout=@var{writeout}
1140This is an optional argument. The only supported value is "immediate".
1141This means that host page cache will be used to read and write data but
1142write notification will be sent to the guest only when the data has been
1143reported as written by the storage subsystem.
1144@item readonly
1145Enables exporting 9p share as a readonly mount for guests. By default
1146read-write access is given.
1147@item socket=@var{socket}
1148Enables proxy filesystem driver to use passed socket file for
1149communicating with virtfs-proxy-helper. Usually a helper like libvirt
1150will create socketpair and pass one of the fds as sock_fd
1151@item sock_fd
1152Enables proxy filesystem driver to use passed 'sock_fd' as the socket
1153descriptor for interfacing with virtfs-proxy-helper
1154@item fmode=@var{fmode}
1155Specifies the default mode for newly created files on the host. Works only
1156with security models "mapped-xattr" and "mapped-file".
1157@item dmode=@var{dmode}
1158Specifies the default mode for newly created directories on the host. Works
1159only with security models "mapped-xattr" and "mapped-file".
1160@end table
1161ETEXI
1162
1163DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
1164    "-virtfs_synth Create synthetic file system image\n",
1165    QEMU_ARCH_ALL)
1166STEXI
1167@item -virtfs_synth
1168@findex -virtfs_synth
1169Create synthetic file system image
1170ETEXI
1171
1172DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
1173    "-iscsi [user=user][,password=password]\n"
1174    "       [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1175    "       [,initiator-name=initiator-iqn][,id=target-iqn]\n"
1176    "       [,timeout=timeout]\n"
1177    "                iSCSI session parameters\n", QEMU_ARCH_ALL)
1178
1179STEXI
1180@item -iscsi
1181@findex -iscsi
1182Configure iSCSI session parameters.
1183ETEXI
1184
1185STEXI
1186@end table
1187ETEXI
1188DEFHEADING()
1189
1190DEFHEADING(USB options:)
1191STEXI
1192@table @option
1193ETEXI
1194
1195DEF("usb", 0, QEMU_OPTION_usb,
1196    "-usb            enable the USB driver (if it is not used by default yet)\n",
1197    QEMU_ARCH_ALL)
1198STEXI
1199@item -usb
1200@findex -usb
1201Enable the USB driver (if it is not used by default yet).
1202ETEXI
1203
1204DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
1205    "-usbdevice name add the host or guest USB device 'name'\n",
1206    QEMU_ARCH_ALL)
1207STEXI
1208
1209@item -usbdevice @var{devname}
1210@findex -usbdevice
1211Add the USB device @var{devname}. Note that this option is deprecated,
1212please use @code{-device usb-...} instead. @xref{usb_devices}.
1213
1214@table @option
1215
1216@item mouse
1217Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1218
1219@item tablet
1220Pointer device that uses absolute coordinates (like a touchscreen). This
1221means QEMU is able to report the mouse position without having to grab the
1222mouse. Also overrides the PS/2 mouse emulation when activated.
1223
1224@item disk:[format=@var{format}]:@var{file}
1225Mass storage device based on file. The optional @var{format} argument
1226will be used rather than detecting the format. Can be used to specify
1227@code{format=raw} to avoid interpreting an untrusted format header.
1228
1229@item host:@var{bus}.@var{addr}
1230Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
1231
1232@item host:@var{vendor_id}:@var{product_id}
1233Pass through the host device identified by @var{vendor_id}:@var{product_id}
1234(Linux only).
1235
1236@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
1237Serial converter to host character device @var{dev}, see @code{-serial} for the
1238available devices.
1239
1240@item braille
1241Braille device.  This will use BrlAPI to display the braille output on a real
1242or fake device.
1243
1244@item net:@var{options}
1245Network adapter that supports CDC ethernet and RNDIS protocols.
1246
1247@end table
1248ETEXI
1249
1250STEXI
1251@end table
1252ETEXI
1253DEFHEADING()
1254
1255DEFHEADING(Display options:)
1256STEXI
1257@table @option
1258ETEXI
1259
1260DEF("display", HAS_ARG, QEMU_OPTION_display,
1261    "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1262    "            [,window_close=on|off][,gl=on|off]\n"
1263    "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1264    "-display vnc=<display>[,<optargs>]\n"
1265    "-display curses\n"
1266    "-display none"
1267    "                select display type\n"
1268    "The default display is equivalent to\n"
1269#if defined(CONFIG_GTK)
1270            "\t\"-display gtk\"\n"
1271#elif defined(CONFIG_SDL)
1272            "\t\"-display sdl\"\n"
1273#elif defined(CONFIG_COCOA)
1274            "\t\"-display cocoa\"\n"
1275#elif defined(CONFIG_VNC)
1276            "\t\"-vnc localhost:0,to=99,id=default\"\n"
1277#else
1278            "\t\"-display none\"\n"
1279#endif
1280    , QEMU_ARCH_ALL)
1281STEXI
1282@item -display @var{type}
1283@findex -display
1284Select type of display to use. This option is a replacement for the
1285old style -sdl/-curses/... options. Valid values for @var{type} are
1286@table @option
1287@item sdl
1288Display video output via SDL (usually in a separate graphics
1289window; see the SDL documentation for other possibilities).
1290@item curses
1291Display video output via curses. For graphics device models which
1292support a text mode, QEMU can display this output using a
1293curses/ncurses interface. Nothing is displayed when the graphics
1294device is in graphical mode or if the graphics device does not support
1295a text mode. Generally only the VGA device models support text mode.
1296@item none
1297Do not display video output. The guest will still see an emulated
1298graphics card, but its output will not be displayed to the QEMU
1299user. This option differs from the -nographic option in that it
1300only affects what is done with video output; -nographic also changes
1301the destination of the serial and parallel port data.
1302@item gtk
1303Display video output in a GTK window. This interface provides drop-down
1304menus and other UI elements to configure and control the VM during
1305runtime.
1306@item vnc
1307Start a VNC server on display <arg>
1308@end table
1309ETEXI
1310
1311DEF("nographic", 0, QEMU_OPTION_nographic,
1312    "-nographic      disable graphical output and redirect serial I/Os to console\n",
1313    QEMU_ARCH_ALL)
1314STEXI
1315@item -nographic
1316@findex -nographic
1317Normally, if QEMU is compiled with graphical window support, it displays
1318output such as guest graphics, guest console, and the QEMU monitor in a
1319window. With this option, you can totally disable graphical output so
1320that QEMU is a simple command line application. The emulated serial port
1321is redirected on the console and muxed with the monitor (unless
1322redirected elsewhere explicitly). Therefore, you can still use QEMU to
1323debug a Linux kernel with a serial console. Use @key{C-a h} for help on
1324switching between the console and monitor.
1325ETEXI
1326
1327DEF("curses", 0, QEMU_OPTION_curses,
1328    "-curses         shorthand for -display curses\n",
1329    QEMU_ARCH_ALL)
1330STEXI
1331@item -curses
1332@findex -curses
1333Normally, if QEMU is compiled with graphical window support, it displays
1334output such as guest graphics, guest console, and the QEMU monitor in a
1335window. With this option, QEMU can display the VGA output when in text
1336mode using a curses/ncurses interface. Nothing is displayed in graphical
1337mode.
1338ETEXI
1339
1340DEF("no-frame", 0, QEMU_OPTION_no_frame,
1341    "-no-frame       open SDL window without a frame and window decorations\n",
1342    QEMU_ARCH_ALL)
1343STEXI
1344@item -no-frame
1345@findex -no-frame
1346Do not use decorations for SDL windows and start them using the whole
1347available screen space. This makes the using QEMU in a dedicated desktop
1348workspace more convenient.
1349ETEXI
1350
1351DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1352    "-alt-grab       use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1353    QEMU_ARCH_ALL)
1354STEXI
1355@item -alt-grab
1356@findex -alt-grab
1357Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1358affects the special keys (for fullscreen, monitor-mode switching, etc).
1359ETEXI
1360
1361DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1362    "-ctrl-grab      use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1363    QEMU_ARCH_ALL)
1364STEXI
1365@item -ctrl-grab
1366@findex -ctrl-grab
1367Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1368affects the special keys (for fullscreen, monitor-mode switching, etc).
1369ETEXI
1370
1371DEF("no-quit", 0, QEMU_OPTION_no_quit,
1372    "-no-quit        disable SDL window close capability\n", QEMU_ARCH_ALL)
1373STEXI
1374@item -no-quit
1375@findex -no-quit
1376Disable SDL window close capability.
1377ETEXI
1378
1379DEF("sdl", 0, QEMU_OPTION_sdl,
1380    "-sdl            shorthand for -display sdl\n", QEMU_ARCH_ALL)
1381STEXI
1382@item -sdl
1383@findex -sdl
1384Enable SDL.
1385ETEXI
1386
1387DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1388    "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1389    "       [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1390    "       [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1391    "       [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1392    "       [,tls-ciphers=<list>]\n"
1393    "       [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1394    "       [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1395    "       [,sasl][,password=<secret>][,disable-ticketing]\n"
1396    "       [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1397    "       [,jpeg-wan-compression=[auto|never|always]]\n"
1398    "       [,zlib-glz-wan-compression=[auto|never|always]]\n"
1399    "       [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1400    "       [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1401    "       [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1402    "       [,gl=[on|off]][,rendernode=<file>]\n"
1403    "   enable spice\n"
1404    "   at least one of {port, tls-port} is mandatory\n",
1405    QEMU_ARCH_ALL)
1406STEXI
1407@item -spice @var{option}[,@var{option}[,...]]
1408@findex -spice
1409Enable the spice remote desktop protocol. Valid options are
1410
1411@table @option
1412
1413@item port=<nr>
1414Set the TCP port spice is listening on for plaintext channels.
1415
1416@item addr=<addr>
1417Set the IP address spice is listening on.  Default is any address.
1418
1419@item ipv4
1420@itemx ipv6
1421@itemx unix
1422Force using the specified IP version.
1423
1424@item password=<secret>
1425Set the password you need to authenticate.
1426
1427@item sasl
1428Require that the client use SASL to authenticate with the spice.
1429The exact choice of authentication method used is controlled from the
1430system / user's SASL configuration file for the 'qemu' service. This
1431is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1432unprivileged user, an environment variable SASL_CONF_PATH can be used
1433to make it search alternate locations for the service config.
1434While some SASL auth methods can also provide data encryption (eg GSSAPI),
1435it is recommended that SASL always be combined with the 'tls' and
1436'x509' settings to enable use of SSL and server certificates. This
1437ensures a data encryption preventing compromise of authentication
1438credentials.
1439
1440@item disable-ticketing
1441Allow client connects without authentication.
1442
1443@item disable-copy-paste
1444Disable copy paste between the client and the guest.
1445
1446@item disable-agent-file-xfer
1447Disable spice-vdagent based file-xfer between the client and the guest.
1448
1449@item tls-port=<nr>
1450Set the TCP port spice is listening on for encrypted channels.
1451
1452@item x509-dir=<dir>
1453Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1454
1455@item x509-key-file=<file>
1456@itemx x509-key-password=<file>
1457@itemx x509-cert-file=<file>
1458@itemx x509-cacert-file=<file>
1459@itemx x509-dh-key-file=<file>
1460The x509 file names can also be configured individually.
1461
1462@item tls-ciphers=<list>
1463Specify which ciphers to use.
1464
1465@item tls-channel=[main|display|cursor|inputs|record|playback]
1466@itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1467Force specific channel to be used with or without TLS encryption.  The
1468options can be specified multiple times to configure multiple
1469channels.  The special name "default" can be used to set the default
1470mode.  For channels which are not explicitly forced into one mode the
1471spice client is allowed to pick tls/plaintext as he pleases.
1472
1473@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1474Configure image compression (lossless).
1475Default is auto_glz.
1476
1477@item jpeg-wan-compression=[auto|never|always]
1478@itemx zlib-glz-wan-compression=[auto|never|always]
1479Configure wan image compression (lossy for slow links).
1480Default is auto.
1481
1482@item streaming-video=[off|all|filter]
1483Configure video stream detection.  Default is off.
1484
1485@item agent-mouse=[on|off]
1486Enable/disable passing mouse events via vdagent.  Default is on.
1487
1488@item playback-compression=[on|off]
1489Enable/disable audio stream compression (using celt 0.5.1).  Default is on.
1490
1491@item seamless-migration=[on|off]
1492Enable/disable spice seamless migration. Default is off.
1493
1494@item gl=[on|off]
1495Enable/disable OpenGL context. Default is off.
1496
1497@item rendernode=<file>
1498DRM render node for OpenGL rendering. If not specified, it will pick
1499the first available. (Since 2.9)
1500
1501@end table
1502ETEXI
1503
1504DEF("portrait", 0, QEMU_OPTION_portrait,
1505    "-portrait       rotate graphical output 90 deg left (only PXA LCD)\n",
1506    QEMU_ARCH_ALL)
1507STEXI
1508@item -portrait
1509@findex -portrait
1510Rotate graphical output 90 deg left (only PXA LCD).
1511ETEXI
1512
1513DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1514    "-rotate <deg>   rotate graphical output some deg left (only PXA LCD)\n",
1515    QEMU_ARCH_ALL)
1516STEXI
1517@item -rotate @var{deg}
1518@findex -rotate
1519Rotate graphical output some deg left (only PXA LCD).
1520ETEXI
1521
1522DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1523    "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1524    "                select video card type\n", QEMU_ARCH_ALL)
1525STEXI
1526@item -vga @var{type}
1527@findex -vga
1528Select type of VGA card to emulate. Valid values for @var{type} are
1529@table @option
1530@item cirrus
1531Cirrus Logic GD5446 Video card. All Windows versions starting from
1532Windows 95 should recognize and use this graphic card. For optimal
1533performances, use 16 bit color depth in the guest and the host OS.
1534(This card was the default before QEMU 2.2)
1535@item std
1536Standard VGA card with Bochs VBE extensions.  If your guest OS
1537supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1538to use high resolution modes (>= 1280x1024x16) then you should use
1539this option. (This card is the default since QEMU 2.2)
1540@item vmware
1541VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1542recent XFree86/XOrg server or Windows guest with a driver for this
1543card.
1544@item qxl
1545QXL paravirtual graphic card.  It is VGA compatible (including VESA
15462.0 VBE support).  Works best with qxl guest drivers installed though.
1547Recommended choice when using the spice protocol.
1548@item tcx
1549(sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1550sun4m machines and offers both 8-bit and 24-bit colour depths at a
1551fixed resolution of 1024x768.
1552@item cg3
1553(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1554for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1555resolutions aimed at people wishing to run older Solaris versions.
1556@item virtio
1557Virtio VGA card.
1558@item none
1559Disable VGA card.
1560@end table
1561ETEXI
1562
1563DEF("full-screen", 0, QEMU_OPTION_full_screen,
1564    "-full-screen    start in full screen\n", QEMU_ARCH_ALL)
1565STEXI
1566@item -full-screen
1567@findex -full-screen
1568Start in full screen.
1569ETEXI
1570
1571DEF("g", 1, QEMU_OPTION_g ,
1572    "-g WxH[xDEPTH]  Set the initial graphical resolution and depth\n",
1573    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1574STEXI
1575@item -g @var{width}x@var{height}[x@var{depth}]
1576@findex -g
1577Set the initial graphical resolution and depth (PPC, SPARC only).
1578ETEXI
1579
1580DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1581    "-vnc <display>  shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1582STEXI
1583@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1584@findex -vnc
1585Normally, if QEMU is compiled with graphical window support, it displays
1586output such as guest graphics, guest console, and the QEMU monitor in a
1587window. With this option, you can have QEMU listen on VNC display
1588@var{display} and redirect the VGA display over the VNC session. It is
1589very useful to enable the usb tablet device when using this option
1590(option @option{-device usb-tablet}). When using the VNC display, you
1591must use the @option{-k} parameter to set the keyboard layout if you are
1592not using en-us. Valid syntax for the @var{display} is
1593
1594@table @option
1595
1596@item to=@var{L}
1597
1598With this option, QEMU will try next available VNC @var{display}s, until the
1599number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1600available, e.g. port 5900+@var{display} is already used by another
1601application. By default, to=0.
1602
1603@item @var{host}:@var{d}
1604
1605TCP connections will only be allowed from @var{host} on display @var{d}.
1606By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1607be omitted in which case the server will accept connections from any host.
1608
1609@item unix:@var{path}
1610
1611Connections will be allowed over UNIX domain sockets where @var{path} is the
1612location of a unix socket to listen for connections on.
1613
1614@item none
1615
1616VNC is initialized but not started. The monitor @code{change} command
1617can be used to later start the VNC server.
1618
1619@end table
1620
1621Following the @var{display} value there may be one or more @var{option} flags
1622separated by commas. Valid options are
1623
1624@table @option
1625
1626@item reverse
1627
1628Connect to a listening VNC client via a ``reverse'' connection. The
1629client is specified by the @var{display}. For reverse network
1630connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1631is a TCP port number, not a display number.
1632
1633@item websocket
1634
1635Opens an additional TCP listening port dedicated to VNC Websocket connections.
1636If a bare @var{websocket} option is given, the Websocket port is
16375700+@var{display}. An alternative port can be specified with the
1638syntax @code{websocket}=@var{port}.
1639
1640If @var{host} is specified connections will only be allowed from this host.
1641It is possible to control the websocket listen address independently, using
1642the syntax @code{websocket}=@var{host}:@var{port}.
1643
1644If no TLS credentials are provided, the websocket connection runs in
1645unencrypted mode. If TLS credentials are provided, the websocket connection
1646requires encrypted client connections.
1647
1648@item password
1649
1650Require that password based authentication is used for client connections.
1651
1652The password must be set separately using the @code{set_password} command in
1653the @ref{pcsys_monitor}. The syntax to change your password is:
1654@code{set_password <protocol> <password>} where <protocol> could be either
1655"vnc" or "spice".
1656
1657If you would like to change <protocol> password expiration, you should use
1658@code{expire_password <protocol> <expiration-time>} where expiration time could
1659be one of the following options: now, never, +seconds or UNIX time of
1660expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1661to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1662date and time).
1663
1664You can also use keywords "now" or "never" for the expiration time to
1665allow <protocol> password to expire immediately or never expire.
1666
1667@item tls-creds=@var{ID}
1668
1669Provides the ID of a set of TLS credentials to use to secure the
1670VNC server. They will apply to both the normal VNC server socket
1671and the websocket socket (if enabled). Setting TLS credentials
1672will cause the VNC server socket to enable the VeNCrypt auth
1673mechanism.  The credentials should have been previously created
1674using the @option{-object tls-creds} argument.
1675
1676The @option{tls-creds} parameter obsoletes the @option{tls},
1677@option{x509}, and @option{x509verify} options, and as such
1678it is not permitted to set both new and old type options at
1679the same time.
1680
1681@item tls
1682
1683Require that client use TLS when communicating with the VNC server. This
1684uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1685attack. It is recommended that this option be combined with either the
1686@option{x509} or @option{x509verify} options.
1687
1688This option is now deprecated in favor of using the @option{tls-creds}
1689argument.
1690
1691@item x509=@var{/path/to/certificate/dir}
1692
1693Valid if @option{tls} is specified. Require that x509 credentials are used
1694for negotiating the TLS session. The server will send its x509 certificate
1695to the client. It is recommended that a password be set on the VNC server
1696to provide authentication of the client when this is used. The path following
1697this option specifies where the x509 certificates are to be loaded from.
1698See the @ref{vnc_security} section for details on generating certificates.
1699
1700This option is now deprecated in favour of using the @option{tls-creds}
1701argument.
1702
1703@item x509verify=@var{/path/to/certificate/dir}
1704
1705Valid if @option{tls} is specified. Require that x509 credentials are used
1706for negotiating the TLS session. The server will send its x509 certificate
1707to the client, and request that the client send its own x509 certificate.
1708The server will validate the client's certificate against the CA certificate,
1709and reject clients when validation fails. If the certificate authority is
1710trusted, this is a sufficient authentication mechanism. You may still wish
1711to set a password on the VNC server as a second authentication layer. The
1712path following this option specifies where the x509 certificates are to
1713be loaded from. See the @ref{vnc_security} section for details on generating
1714certificates.
1715
1716This option is now deprecated in favour of using the @option{tls-creds}
1717argument.
1718
1719@item sasl
1720
1721Require that the client use SASL to authenticate with the VNC server.
1722The exact choice of authentication method used is controlled from the
1723system / user's SASL configuration file for the 'qemu' service. This
1724is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1725unprivileged user, an environment variable SASL_CONF_PATH can be used
1726to make it search alternate locations for the service config.
1727While some SASL auth methods can also provide data encryption (eg GSSAPI),
1728it is recommended that SASL always be combined with the 'tls' and
1729'x509' settings to enable use of SSL and server certificates. This
1730ensures a data encryption preventing compromise of authentication
1731credentials. See the @ref{vnc_security} section for details on using
1732SASL authentication.
1733
1734@item acl
1735
1736Turn on access control lists for checking of the x509 client certificate
1737and SASL party. For x509 certs, the ACL check is made against the
1738certificate's distinguished name. This is something that looks like
1739@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1740made against the username, which depending on the SASL plugin, may
1741include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1742When the @option{acl} flag is set, the initial access list will be
1743empty, with a @code{deny} policy. Thus no one will be allowed to
1744use the VNC server until the ACLs have been loaded. This can be
1745achieved using the @code{acl} monitor command.
1746
1747@item lossy
1748
1749Enable lossy compression methods (gradient, JPEG, ...). If this
1750option is set, VNC client may receive lossy framebuffer updates
1751depending on its encoding settings. Enabling this option can save
1752a lot of bandwidth at the expense of quality.
1753
1754@item non-adaptive
1755
1756Disable adaptive encodings. Adaptive encodings are enabled by default.
1757An adaptive encoding will try to detect frequently updated screen regions,
1758and send updates in these regions using a lossy encoding (like JPEG).
1759This can be really helpful to save bandwidth when playing videos. Disabling
1760adaptive encodings restores the original static behavior of encodings
1761like Tight.
1762
1763@item share=[allow-exclusive|force-shared|ignore]
1764
1765Set display sharing policy.  'allow-exclusive' allows clients to ask
1766for exclusive access.  As suggested by the rfb spec this is
1767implemented by dropping other connections.  Connecting multiple
1768clients in parallel requires all clients asking for a shared session
1769(vncviewer: -shared switch).  This is the default.  'force-shared'
1770disables exclusive client access.  Useful for shared desktop sessions,
1771where you don't want someone forgetting specify -shared disconnect
1772everybody else.  'ignore' completely ignores the shared flag and
1773allows everybody connect unconditionally.  Doesn't conform to the rfb
1774spec but is traditional QEMU behavior.
1775
1776@item key-delay-ms
1777
1778Set keyboard delay, for key down and key up events, in milliseconds.
1779Default is 10.  Keyboards are low-bandwidth devices, so this slowdown
1780can help the device and guest to keep up and not lose events in case
1781events are arriving in bulk.  Possible causes for the latter are flaky
1782network connections, or scripts for automated testing.
1783
1784@end table
1785ETEXI
1786
1787STEXI
1788@end table
1789ETEXI
1790ARCHHEADING(, QEMU_ARCH_I386)
1791
1792ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1793STEXI
1794@table @option
1795ETEXI
1796
1797DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1798    "-win2k-hack     use it when installing Windows 2000 to avoid a disk full bug\n",
1799    QEMU_ARCH_I386)
1800STEXI
1801@item -win2k-hack
1802@findex -win2k-hack
1803Use it when installing Windows 2000 to avoid a disk full bug. After
1804Windows 2000 is installed, you no longer need this option (this option
1805slows down the IDE transfers).
1806ETEXI
1807
1808HXCOMM Deprecated by -rtc
1809DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1810
1811DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1812    "-no-fd-bootchk  disable boot signature checking for floppy disks\n",
1813    QEMU_ARCH_I386)
1814STEXI
1815@item -no-fd-bootchk
1816@findex -no-fd-bootchk
1817Disable boot signature checking for floppy disks in BIOS. May
1818be needed to boot from old floppy disks.
1819ETEXI
1820
1821DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1822           "-no-acpi        disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1823STEXI
1824@item -no-acpi
1825@findex -no-acpi
1826Disable ACPI (Advanced Configuration and Power Interface) support. Use
1827it if your guest OS complains about ACPI problems (PC target machine
1828only).
1829ETEXI
1830
1831DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1832    "-no-hpet        disable HPET\n", QEMU_ARCH_I386)
1833STEXI
1834@item -no-hpet
1835@findex -no-hpet
1836Disable HPET support.
1837ETEXI
1838
1839DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1840    "-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"
1841    "                ACPI table description\n", QEMU_ARCH_I386)
1842STEXI
1843@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}]...]
1844@findex -acpitable
1845Add ACPI table with specified header fields and context from specified files.
1846For file=, take whole ACPI table from the specified files, including all
1847ACPI headers (possible overridden by other options).
1848For data=, only data
1849portion of the table is used, all header information is specified in the
1850command line.
1851If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1852fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1853to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1854spec.
1855ETEXI
1856
1857DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1858    "-smbios file=binary\n"
1859    "                load SMBIOS entry from binary file\n"
1860    "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1861    "              [,uefi=on|off]\n"
1862    "                specify SMBIOS type 0 fields\n"
1863    "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1864    "              [,uuid=uuid][,sku=str][,family=str]\n"
1865    "                specify SMBIOS type 1 fields\n"
1866    "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1867    "              [,asset=str][,location=str]\n"
1868    "                specify SMBIOS type 2 fields\n"
1869    "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1870    "              [,sku=str]\n"
1871    "                specify SMBIOS type 3 fields\n"
1872    "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1873    "              [,asset=str][,part=str]\n"
1874    "                specify SMBIOS type 4 fields\n"
1875    "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1876    "               [,asset=str][,part=str][,speed=%d]\n"
1877    "                specify SMBIOS type 17 fields\n",
1878    QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1879STEXI
1880@item -smbios file=@var{binary}
1881@findex -smbios
1882Load SMBIOS entry from binary file.
1883
1884@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1885Specify SMBIOS type 0 fields
1886
1887@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}]
1888Specify SMBIOS type 1 fields
1889
1890@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}]
1891Specify SMBIOS type 2 fields
1892
1893@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1894Specify SMBIOS type 3 fields
1895
1896@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1897Specify SMBIOS type 4 fields
1898
1899@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}]
1900Specify SMBIOS type 17 fields
1901ETEXI
1902
1903STEXI
1904@end table
1905ETEXI
1906DEFHEADING()
1907
1908DEFHEADING(Network options:)
1909STEXI
1910@table @option
1911ETEXI
1912
1913HXCOMM Legacy slirp options (now moved to -net user):
1914#ifdef CONFIG_SLIRP
1915DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1916DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1917DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1918#ifndef _WIN32
1919DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1920#endif
1921#endif
1922
1923DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1924#ifdef CONFIG_SLIRP
1925    "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1926    "         [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1927    "         [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1928    "         [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1929    "         [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1930#ifndef _WIN32
1931                                             "[,smb=dir[,smbserver=addr]]\n"
1932#endif
1933    "                configure a user mode network backend with ID 'str',\n"
1934    "                its DHCP server and optional services\n"
1935#endif
1936#ifdef _WIN32
1937    "-netdev tap,id=str,ifname=name\n"
1938    "                configure a host TAP network backend with ID 'str'\n"
1939#else
1940    "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1941    "         [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1942    "         [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1943    "         [,poll-us=n]\n"
1944    "                configure a host TAP network backend with ID 'str'\n"
1945    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1946    "                use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1947    "                to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1948    "                to deconfigure it\n"
1949    "                use '[down]script=no' to disable script execution\n"
1950    "                use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1951    "                configure it\n"
1952    "                use 'fd=h' to connect to an already opened TAP interface\n"
1953    "                use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1954    "                use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1955    "                default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1956    "                use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1957    "                use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1958    "                use vhost=on to enable experimental in kernel accelerator\n"
1959    "                    (only has effect for virtio guests which use MSIX)\n"
1960    "                use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1961    "                use 'vhostfd=h' to connect to an already opened vhost net device\n"
1962    "                use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1963    "                use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1964    "                use 'poll-us=n' to speciy the maximum number of microseconds that could be\n"
1965    "                spent on busy polling for vhost net\n"
1966    "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1967    "                configure a host TAP network backend with ID 'str' that is\n"
1968    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1969    "                using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1970#endif
1971#ifdef __linux__
1972    "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1973    "         [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1974    "         [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1975    "         [,rxcookie=rxcookie][,offset=offset]\n"
1976    "                configure a network backend with ID 'str' connected to\n"
1977    "                an Ethernet over L2TPv3 pseudowire.\n"
1978    "                Linux kernel 3.3+ as well as most routers can talk\n"
1979    "                L2TPv3. This transport allows connecting a VM to a VM,\n"
1980    "                VM to a router and even VM to Host. It is a nearly-universal\n"
1981    "                standard (RFC3391). Note - this implementation uses static\n"
1982    "                pre-configured tunnels (same as the Linux kernel).\n"
1983    "                use 'src=' to specify source address\n"
1984    "                use 'dst=' to specify destination address\n"
1985    "                use 'udp=on' to specify udp encapsulation\n"
1986    "                use 'srcport=' to specify source udp port\n"
1987    "                use 'dstport=' to specify destination udp port\n"
1988    "                use 'ipv6=on' to force v6\n"
1989    "                L2TPv3 uses cookies to prevent misconfiguration as\n"
1990    "                well as a weak security measure\n"
1991    "                use 'rxcookie=0x012345678' to specify a rxcookie\n"
1992    "                use 'txcookie=0x012345678' to specify a txcookie\n"
1993    "                use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1994    "                use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1995    "                use 'pincounter=on' to work around broken counter handling in peer\n"
1996    "                use 'offset=X' to add an extra offset between header and data\n"
1997#endif
1998    "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1999    "                configure a network backend to connect to another network\n"
2000    "                using a socket connection\n"
2001    "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
2002    "                configure a network backend to connect to a multicast maddr and port\n"
2003    "                use 'localaddr=addr' to specify the host address to send packets from\n"
2004    "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
2005    "                configure a network backend to connect to another network\n"
2006    "                using an UDP tunnel\n"
2007#ifdef CONFIG_VDE
2008    "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
2009    "                configure a network backend to connect to port 'n' of a vde switch\n"
2010    "                running on host and listening for incoming connections on 'socketpath'.\n"
2011    "                Use group 'groupname' and mode 'octalmode' to change default\n"
2012    "                ownership and permissions for communication port.\n"
2013#endif
2014#ifdef CONFIG_NETMAP
2015    "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
2016    "                attach to the existing netmap-enabled network interface 'name', or to a\n"
2017    "                VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
2018    "                netmap device, defaults to '/dev/netmap')\n"
2019#endif
2020    "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
2021    "                configure a vhost-user network, backed by a chardev 'dev'\n"
2022    "-netdev hubport,id=str,hubid=n\n"
2023    "                configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL)
2024DEF("net", HAS_ARG, QEMU_OPTION_net,
2025    "-net nic[,vlan=n][,netdev=nd][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2026    "                configure or create an on-board (or machine default) NIC and\n"
2027    "                connect it either to VLAN 'n' or the netdev 'nd' (for pluggable\n"
2028    "                NICs please use '-device devtype,netdev=nd' instead)\n"
2029    "-net dump[,vlan=n][,file=f][,len=n]\n"
2030    "                dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
2031    "-net none       use it alone to have zero network devices. If no -net option\n"
2032    "                is provided, the default is '-net nic -net user'\n"
2033    "-net ["
2034#ifdef CONFIG_SLIRP
2035    "user|"
2036#endif
2037    "tap|"
2038    "bridge|"
2039#ifdef CONFIG_VDE
2040    "vde|"
2041#endif
2042#ifdef CONFIG_NETMAP
2043    "netmap|"
2044#endif
2045    "socket][,vlan=n][,option][,option][,...]\n"
2046    "                old way to initialize a host network interface\n"
2047    "                (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2048STEXI
2049@item -net nic[,vlan=@var{n}][,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2050@findex -net
2051Configure or create an on-board (or machine default) Network Interface Card
2052(NIC) and connect it either to VLAN @var{n} (@var{n} = 0 is the default), or
2053to the netdev @var{nd}. The NIC is an e1000 by default on the PC
2054target. Optionally, the MAC address can be changed to @var{mac}, the
2055device address set to @var{addr} (PCI cards only),
2056and a @var{name} can be assigned for use in monitor commands.
2057Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2058that the card should have; this option currently only affects virtio cards; set
2059@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2060NIC is created.  QEMU can emulate several different models of network card.
2061Valid values for @var{type} are
2062@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
2063@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
2064@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
2065Not all devices are supported on all targets.  Use @code{-net nic,model=help}
2066for a list of available devices for your target.
2067
2068@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2069@findex -netdev
2070@item -net user[,@var{option}][,@var{option}][,...]
2071Use the user mode network stack which requires no administrator
2072privilege to run. Valid options are:
2073
2074@table @option
2075@item vlan=@var{n}
2076Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
2077
2078@item id=@var{id}
2079@itemx name=@var{name}
2080Assign symbolic name for use in monitor commands.
2081
2082@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
2083be enabled.  If neither is specified both protocols are enabled.
2084
2085@item net=@var{addr}[/@var{mask}]
2086Set IP network address the guest will see. Optionally specify the netmask,
2087either in the form a.b.c.d or as number of valid top-most bits. Default is
208810.0.2.0/24.
2089
2090@item host=@var{addr}
2091Specify the guest-visible address of the host. Default is the 2nd IP in the
2092guest network, i.e. x.x.x.2.
2093
2094@item ipv6-net=@var{addr}[/@var{int}]
2095Set IPv6 network address the guest will see (default is fec0::/64). The
2096network prefix is given in the usual hexadecimal IPv6 address
2097notation. The prefix size is optional, and is given as the number of
2098valid top-most bits (default is 64).
2099
2100@item ipv6-host=@var{addr}
2101Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2102the guest network, i.e. xxxx::2.
2103
2104@item restrict=on|off
2105If this option is enabled, the guest will be isolated, i.e. it will not be
2106able to contact the host and no guest IP packets will be routed over the host
2107to the outside. This option does not affect any explicitly set forwarding rules.
2108
2109@item hostname=@var{name}
2110Specifies the client hostname reported by the built-in DHCP server.
2111
2112@item dhcpstart=@var{addr}
2113Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2114is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2115
2116@item dns=@var{addr}
2117Specify the guest-visible address of the virtual nameserver. The address must
2118be different from the host address. Default is the 3rd IP in the guest network,
2119i.e. x.x.x.3.
2120
2121@item ipv6-dns=@var{addr}
2122Specify the guest-visible address of the IPv6 virtual nameserver. The address
2123must be different from the host address. Default is the 3rd IP in the guest
2124network, i.e. xxxx::3.
2125
2126@item dnssearch=@var{domain}
2127Provides an entry for the domain-search list sent by the built-in
2128DHCP server. More than one domain suffix can be transmitted by specifying
2129this option multiple times. If supported, this will cause the guest to
2130automatically try to append the given domain suffix(es) in case a domain name
2131can not be resolved.
2132
2133Example:
2134@example
2135qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
2136@end example
2137
2138@item tftp=@var{dir}
2139When using the user mode network stack, activate a built-in TFTP
2140server. The files in @var{dir} will be exposed as the root of a TFTP server.
2141The TFTP client on the guest must be configured in binary mode (use the command
2142@code{bin} of the Unix TFTP client).
2143
2144@item bootfile=@var{file}
2145When using the user mode network stack, broadcast @var{file} as the BOOTP
2146filename. In conjunction with @option{tftp}, this can be used to network boot
2147a guest from a local directory.
2148
2149Example (using pxelinux):
2150@example
2151qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2152@end example
2153
2154@item smb=@var{dir}[,smbserver=@var{addr}]
2155When using the user mode network stack, activate a built-in SMB
2156server so that Windows OSes can access to the host files in @file{@var{dir}}
2157transparently. The IP address of the SMB server can be set to @var{addr}. By
2158default the 4th IP in the guest network is used, i.e. x.x.x.4.
2159
2160In the guest Windows OS, the line:
2161@example
216210.0.2.4 smbserver
2163@end example
2164must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2165or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2166
2167Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2168
2169Note that a SAMBA server must be installed on the host OS.
2170QEMU was tested successfully with smbd versions from Red Hat 9,
2171Fedora Core 3 and OpenSUSE 11.x.
2172
2173@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2174Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2175the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2176@var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2177given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2178be bound to a specific host interface. If no connection type is set, TCP is
2179used. This option can be given multiple times.
2180
2181For example, to redirect host X11 connection from screen 1 to guest
2182screen 0, use the following:
2183
2184@example
2185# on the host
2186qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
2187# this host xterm should open in the guest X11 server
2188xterm -display :1
2189@end example
2190
2191To redirect telnet connections from host port 5555 to telnet port on
2192the guest, use the following:
2193
2194@example
2195# on the host
2196qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
2197telnet localhost 5555
2198@end example
2199
2200Then when you use on the host @code{telnet localhost 5555}, you
2201connect to the guest telnet server.
2202
2203@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2204@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2205Forward guest TCP connections to the IP address @var{server} on port @var{port}
2206to the character device @var{dev} or to a program executed by @var{cmd:command}
2207which gets spawned for each connection. This option can be given multiple times.
2208
2209You can either use a chardev directly and have that one used throughout QEMU's
2210lifetime, like in the following example:
2211
2212@example
2213# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
2214# the guest accesses it
2215qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
2216@end example
2217
2218Or you can execute a command on every TCP connection established by the guest,
2219so that QEMU behaves similar to an inetd process for that virtual server:
2220
2221@example
2222# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
2223# and connect the TCP stream to its stdin/stdout
2224qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2225@end example
2226
2227@end table
2228
2229Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
2230processed and applied to -net user. Mixing them with the new configuration
2231syntax gives undefined results. Their use for new applications is discouraged
2232as they will be removed from future versions.
2233
2234@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2235@itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2236Connect the host TAP network interface @var{name} to VLAN @var{n}.
2237
2238Use the network script @var{file} to configure it and the network script
2239@var{dfile} to deconfigure it. If @var{name} is not provided, the OS
2240automatically provides one. The default network configure script is
2241@file{/etc/qemu-ifup} and the default network deconfigure script is
2242@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
2243to disable script execution.
2244
2245If running QEMU as an unprivileged user, use the network helper
2246@var{helper} to configure the TAP interface and attach it to the bridge.
2247The default network helper executable is @file{/path/to/qemu-bridge-helper}
2248and the default bridge device is @file{br0}.
2249
2250@option{fd}=@var{h} can be used to specify the handle of an already
2251opened host TAP interface.
2252
2253Examples:
2254
2255@example
2256#launch a QEMU instance with the default network script
2257qemu-system-i386 linux.img -net nic -net tap
2258@end example
2259
2260@example
2261#launch a QEMU instance with two NICs, each one connected
2262#to a TAP device
2263qemu-system-i386 linux.img \
2264                 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
2265                 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
2266@end example
2267
2268@example
2269#launch a QEMU instance with the default network helper to
2270#connect a TAP device to bridge br0
2271qemu-system-i386 linux.img \
2272                 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
2273@end example
2274
2275@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
2276@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
2277Connect a host TAP network interface to a host bridge device.
2278
2279Use the network helper @var{helper} to configure the TAP interface and
2280attach it to the bridge. The default network helper executable is
2281@file{/path/to/qemu-bridge-helper} and the default bridge
2282device is @file{br0}.
2283
2284Examples:
2285
2286@example
2287#launch a QEMU instance with the default network helper to
2288#connect a TAP device to bridge br0
2289qemu-system-i386 linux.img -net bridge -net nic,model=virtio
2290@end example
2291
2292@example
2293#launch a QEMU instance with the default network helper to
2294#connect a TAP device to bridge qemubr0
2295qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
2296@end example
2297
2298@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2299@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2300
2301Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
2302machine using a TCP socket connection. If @option{listen} is
2303specified, QEMU waits for incoming connections on @var{port}
2304(@var{host} is optional). @option{connect} is used to connect to
2305another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
2306specifies an already opened TCP socket.
2307
2308Example:
2309@example
2310# launch a first QEMU instance
2311qemu-system-i386 linux.img \
2312                 -net nic,macaddr=52:54:00:12:34:56 \
2313                 -net socket,listen=:1234
2314# connect the VLAN 0 of this instance to the VLAN 0
2315# of the first instance
2316qemu-system-i386 linux.img \
2317                 -net nic,macaddr=52:54:00:12:34:57 \
2318                 -net socket,connect=127.0.0.1:1234
2319@end example
2320
2321@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2322@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2323
2324Create a VLAN @var{n} shared with another QEMU virtual
2325machines using a UDP multicast socket, effectively making a bus for
2326every QEMU with same multicast address @var{maddr} and @var{port}.
2327NOTES:
2328@enumerate
2329@item
2330Several QEMU can be running on different hosts and share same bus (assuming
2331correct multicast setup for these hosts).
2332@item
2333mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
2334@url{http://user-mode-linux.sf.net}.
2335@item
2336Use @option{fd=h} to specify an already opened UDP multicast socket.
2337@end enumerate
2338
2339Example:
2340@example
2341# launch one QEMU instance
2342qemu-system-i386 linux.img \
2343                 -net nic,macaddr=52:54:00:12:34:56 \
2344                 -net socket,mcast=230.0.0.1:1234
2345# launch another QEMU instance on same "bus"
2346qemu-system-i386 linux.img \
2347                 -net nic,macaddr=52:54:00:12:34:57 \
2348                 -net socket,mcast=230.0.0.1:1234
2349# launch yet another QEMU instance on same "bus"
2350qemu-system-i386 linux.img \
2351                 -net nic,macaddr=52:54:00:12:34:58 \
2352                 -net socket,mcast=230.0.0.1:1234
2353@end example
2354
2355Example (User Mode Linux compat.):
2356@example
2357# launch QEMU instance (note mcast address selected
2358# is UML's default)
2359qemu-system-i386 linux.img \
2360                 -net nic,macaddr=52:54:00:12:34:56 \
2361                 -net socket,mcast=239.192.168.1:1102
2362# launch UML
2363/path/to/linux ubd0=/path/to/root_fs eth0=mcast
2364@end example
2365
2366Example (send packets from host's 1.2.3.4):
2367@example
2368qemu-system-i386 linux.img \
2369                 -net nic,macaddr=52:54:00:12:34:56 \
2370                 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2371@end example
2372
2373@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}]
2374@itemx -net l2tpv3[,vlan=@var{n}][,name=@var{name}],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}]
2375Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
2376protocol to transport Ethernet (and other Layer 2) data frames between
2377two systems. It is present in routers, firewalls and the Linux kernel
2378(from version 3.3 onwards).
2379
2380This transport allows a VM to communicate to another VM, router or firewall directly.
2381
2382@table @option
2383@item src=@var{srcaddr}
2384    source address (mandatory)
2385@item dst=@var{dstaddr}
2386    destination address (mandatory)
2387@item udp
2388    select udp encapsulation (default is ip).
2389@item srcport=@var{srcport}
2390    source udp port.
2391@item dstport=@var{dstport}
2392    destination udp port.
2393@item ipv6
2394    force v6, otherwise defaults to v4.
2395@item rxcookie=@var{rxcookie}
2396@itemx txcookie=@var{txcookie}
2397    Cookies are a weak form of security in the l2tpv3 specification.
2398Their function is mostly to prevent misconfiguration. By default they are 32
2399bit.
2400@item cookie64
2401    Set cookie size to 64 bit instead of the default 32
2402@item counter=off
2403    Force a 'cut-down' L2TPv3 with no counter as in
2404draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2405@item pincounter=on
2406    Work around broken counter handling in peer. This may also help on
2407networks which have packet reorder.
2408@item offset=@var{offset}
2409    Add an extra offset between header and data
2410@end table
2411
2412For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2413on the remote Linux host 1.2.3.4:
2414@example
2415# Setup tunnel on linux host using raw ip as encapsulation
2416# on 1.2.3.4
2417ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2418    encap udp udp_sport 16384 udp_dport 16384
2419ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2420    0xFFFFFFFF peer_session_id 0xFFFFFFFF
2421ifconfig vmtunnel0 mtu 1500
2422ifconfig vmtunnel0 up
2423brctl addif br-lan vmtunnel0
2424
2425
2426# on 4.3.2.1
2427# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2428
2429qemu-system-i386 linux.img -net nic -net l2tpv3,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter
2430
2431
2432@end example
2433
2434@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2435@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2436Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
2437listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2438and MODE @var{octalmode} to change default ownership and permissions for
2439communication port. This option is only available if QEMU has been compiled
2440with vde support enabled.
2441
2442Example:
2443@example
2444# launch vde switch
2445vde_switch -F -sock /tmp/myswitch
2446# launch QEMU instance
2447qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
2448@end example
2449
2450@item -netdev hubport,id=@var{id},hubid=@var{hubid}
2451
2452Create a hub port on QEMU "vlan" @var{hubid}.
2453
2454The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
2455netdev.  @code{-net} and @code{-device} with parameter @option{vlan} create the
2456required hub automatically.
2457
2458@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2459
2460Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2461be a unix domain socket backed one. The vhost-user uses a specifically defined
2462protocol to pass vhost ioctl replacement messages to an application on the other
2463end of the socket. On non-MSIX guests, the feature can be forced with
2464@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2465be created for multiqueue vhost-user.
2466
2467Example:
2468@example
2469qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2470     -numa node,memdev=mem \
2471     -chardev socket,id=chr0,path=/path/to/socket \
2472     -netdev type=vhost-user,id=net0,chardev=chr0 \
2473     -device virtio-net-pci,netdev=net0
2474@end example
2475
2476@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2477Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2478At most @var{len} bytes (64k by default) per packet are stored. The file format is
2479libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2480Note: For devices created with '-netdev', use '-object filter-dump,...' instead.
2481
2482@item -net none
2483Indicate that no network devices should be configured. It is used to
2484override the default configuration (@option{-net nic -net user}) which
2485is activated if no @option{-net} options are provided.
2486ETEXI
2487
2488STEXI
2489@end table
2490ETEXI
2491DEFHEADING()
2492
2493DEFHEADING(Character device options:)
2494
2495DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2496    "-chardev help\n"
2497    "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2498    "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2499    "         [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2500    "         [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2501    "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2502    "         [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2503    "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2504    "         [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2505    "         [,logfile=PATH][,logappend=on|off]\n"
2506    "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2507    "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2508    "         [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2509    "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2510    "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2511    "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2512#ifdef _WIN32
2513    "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2514    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2515#else
2516    "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2517    "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2518#endif
2519#ifdef CONFIG_BRLAPI
2520    "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2521#endif
2522#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2523        || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2524    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2525    "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2526#endif
2527#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2528    "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2529    "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2530#endif
2531#if defined(CONFIG_SPICE)
2532    "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2533    "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2534#endif
2535    , QEMU_ARCH_ALL
2536)
2537
2538STEXI
2539
2540The general form of a character device option is:
2541@table @option
2542@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2543@findex -chardev
2544Backend is one of:
2545@option{null},
2546@option{socket},
2547@option{udp},
2548@option{msmouse},
2549@option{vc},
2550@option{ringbuf},
2551@option{file},
2552@option{pipe},
2553@option{console},
2554@option{serial},
2555@option{pty},
2556@option{stdio},
2557@option{braille},
2558@option{tty},
2559@option{parallel},
2560@option{parport},
2561@option{spicevmc}.
2562@option{spiceport}.
2563The specific backend will determine the applicable options.
2564
2565Use @code{-chardev help} to print all available chardev backend types.
2566
2567All devices must have an id, which can be any string up to 127 characters long.
2568It is used to uniquely identify this device in other command line directives.
2569
2570A character device may be used in multiplexing mode by multiple front-ends.
2571Specify @option{mux=on} to enable this mode.
2572A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2573backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2574If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2575create a multiplexer with your specified ID, and you can then configure multiple
2576front ends to use that chardev ID for their input/output. Up to four different
2577front ends can be connected to a single multiplexed chardev. (Without
2578multiplexing enabled, a chardev can only be used by a single front end.)
2579For instance you could use this to allow a single stdio chardev to be used by
2580two serial ports and the QEMU monitor:
2581
2582@example
2583-chardev stdio,mux=on,id=char0 \
2584-mon chardev=char0,mode=readline \
2585-serial chardev:char0 \
2586-serial chardev:char0
2587@end example
2588
2589You can have more than one multiplexer in a system configuration; for instance
2590you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2591multiplexed between the QEMU monitor and a parallel port:
2592
2593@example
2594-chardev stdio,mux=on,id=char0 \
2595-mon chardev=char0,mode=readline \
2596-parallel chardev:char0 \
2597-chardev tcp,...,mux=on,id=char1 \
2598-serial chardev:char1 \
2599-serial chardev:char1
2600@end example
2601
2602When you're using a multiplexed character device, some escape sequences are
2603interpreted in the input. @xref{mux_keys, Keys in the character backend
2604multiplexer}.
2605
2606Note that some other command line options may implicitly create multiplexed
2607character backends; for instance @option{-serial mon:stdio} creates a
2608multiplexed stdio backend connected to the serial port and the QEMU monitor,
2609and @option{-nographic} also multiplexes the console and the monitor to
2610stdio.
2611
2612There is currently no support for multiplexing in the other direction
2613(where a single QEMU front end takes input and output from multiple chardevs).
2614
2615Every backend supports the @option{logfile} option, which supplies the path
2616to a file to record all data transmitted via the backend. The @option{logappend}
2617option controls whether the log file will be truncated or appended to when
2618opened.
2619
2620@end table
2621
2622The available backends are:
2623
2624@table @option
2625@item -chardev null ,id=@var{id}
2626A void device. This device will not emit any data, and will drop any data it
2627receives. The null backend does not take any options.
2628
2629@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2630
2631Create a two-way stream socket, which can be either a TCP or a unix socket. A
2632unix socket will be created if @option{path} is specified. Behaviour is
2633undefined if TCP options are specified for a unix socket.
2634
2635@option{server} specifies that the socket shall be a listening socket.
2636
2637@option{nowait} specifies that QEMU should not block waiting for a client to
2638connect to a listening socket.
2639
2640@option{telnet} specifies that traffic on the socket should interpret telnet
2641escape sequences.
2642
2643@option{reconnect} sets the timeout for reconnecting on non-server sockets when
2644the remote end goes away.  qemu will delay this many seconds and then attempt
2645to reconnect.  Zero disables reconnecting, and is the default.
2646
2647@option{tls-creds} requests enablement of the TLS protocol for encryption,
2648and specifies the id of the TLS credentials to use for the handshake. The
2649credentials must be previously created with the @option{-object tls-creds}
2650argument.
2651
2652TCP and unix socket options are given below:
2653
2654@table @option
2655
2656@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2657
2658@option{host} for a listening socket specifies the local address to be bound.
2659For a connecting socket species the remote host to connect to. @option{host} is
2660optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2661
2662@option{port} for a listening socket specifies the local port to be bound. For a
2663connecting socket specifies the port on the remote host to connect to.
2664@option{port} can be given as either a port number or a service name.
2665@option{port} is required.
2666
2667@option{to} is only relevant to listening sockets. If it is specified, and
2668@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2669to and including @option{to} until it succeeds. @option{to} must be specified
2670as a port number.
2671
2672@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2673If neither is specified the socket may use either protocol.
2674
2675@option{nodelay} disables the Nagle algorithm.
2676
2677@item unix options: path=@var{path}
2678
2679@option{path} specifies the local path of the unix socket. @option{path} is
2680required.
2681
2682@end table
2683
2684@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2685
2686Sends all traffic from the guest to a remote host over UDP.
2687
2688@option{host} specifies the remote host to connect to. If not specified it
2689defaults to @code{localhost}.
2690
2691@option{port} specifies the port on the remote host to connect to. @option{port}
2692is required.
2693
2694@option{localaddr} specifies the local address to bind to. If not specified it
2695defaults to @code{0.0.0.0}.
2696
2697@option{localport} specifies the local port to bind to. If not specified any
2698available local port will be used.
2699
2700@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2701If neither is specified the device may use either protocol.
2702
2703@item -chardev msmouse ,id=@var{id}
2704
2705Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2706take any options.
2707
2708@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2709
2710Connect to a QEMU text console. @option{vc} may optionally be given a specific
2711size.
2712
2713@option{width} and @option{height} specify the width and height respectively of
2714the console, in pixels.
2715
2716@option{cols} and @option{rows} specify that the console be sized to fit a text
2717console with the given dimensions.
2718
2719@item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2720
2721Create a ring buffer with fixed size @option{size}.
2722@var{size} must be a power of two and defaults to @code{64K}.
2723
2724@item -chardev file ,id=@var{id} ,path=@var{path}
2725
2726Log all traffic received from the guest to a file.
2727
2728@option{path} specifies the path of the file to be opened. This file will be
2729created if it does not already exist, and overwritten if it does. @option{path}
2730is required.
2731
2732@item -chardev pipe ,id=@var{id} ,path=@var{path}
2733
2734Create a two-way connection to the guest. The behaviour differs slightly between
2735Windows hosts and other hosts:
2736
2737On Windows, a single duplex pipe will be created at
2738@file{\\.pipe\@option{path}}.
2739
2740On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2741@file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2742received by the guest. Data written by the guest can be read from
2743@file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2744be present.
2745
2746@option{path} forms part of the pipe path as described above. @option{path} is
2747required.
2748
2749@item -chardev console ,id=@var{id}
2750
2751Send traffic from the guest to QEMU's standard output. @option{console} does not
2752take any options.
2753
2754@option{console} is only available on Windows hosts.
2755
2756@item -chardev serial ,id=@var{id} ,path=@option{path}
2757
2758Send traffic from the guest to a serial device on the host.
2759
2760On Unix hosts serial will actually accept any tty device,
2761not only serial lines.
2762
2763@option{path} specifies the name of the serial device to open.
2764
2765@item -chardev pty ,id=@var{id}
2766
2767Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2768not take any options.
2769
2770@option{pty} is not available on Windows hosts.
2771
2772@item -chardev stdio ,id=@var{id} [,signal=on|off]
2773Connect to standard input and standard output of the QEMU process.
2774
2775@option{signal} controls if signals are enabled on the terminal, that includes
2776exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2777default, use @option{signal=off} to disable it.
2778
2779@item -chardev braille ,id=@var{id}
2780
2781Connect to a local BrlAPI server. @option{braille} does not take any options.
2782
2783@item -chardev tty ,id=@var{id} ,path=@var{path}
2784
2785@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2786DragonFlyBSD hosts.  It is an alias for @option{serial}.
2787
2788@option{path} specifies the path to the tty. @option{path} is required.
2789
2790@item -chardev parallel ,id=@var{id} ,path=@var{path}
2791@itemx -chardev parport ,id=@var{id} ,path=@var{path}
2792
2793@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2794
2795Connect to a local parallel port.
2796
2797@option{path} specifies the path to the parallel port device. @option{path} is
2798required.
2799
2800@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2801
2802@option{spicevmc} is only available when spice support is built in.
2803
2804@option{debug} debug level for spicevmc
2805
2806@option{name} name of spice channel to connect to
2807
2808Connect to a spice virtual machine channel, such as vdiport.
2809
2810@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2811
2812@option{spiceport} is only available when spice support is built in.
2813
2814@option{debug} debug level for spicevmc
2815
2816@option{name} name of spice port to connect to
2817
2818Connect to a spice port, allowing a Spice client to handle the traffic
2819identified by a name (preferably a fqdn).
2820ETEXI
2821
2822STEXI
2823@end table
2824ETEXI
2825DEFHEADING()
2826
2827DEFHEADING(Bluetooth(R) options:)
2828STEXI
2829@table @option
2830ETEXI
2831
2832DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2833    "-bt hci,null    dumb bluetooth HCI - doesn't respond to commands\n" \
2834    "-bt hci,host[:id]\n" \
2835    "                use host's HCI with the given name\n" \
2836    "-bt hci[,vlan=n]\n" \
2837    "                emulate a standard HCI in virtual scatternet 'n'\n" \
2838    "-bt vhci[,vlan=n]\n" \
2839    "                add host computer to virtual scatternet 'n' using VHCI\n" \
2840    "-bt device:dev[,vlan=n]\n" \
2841    "                emulate a bluetooth device 'dev' in scatternet 'n'\n",
2842    QEMU_ARCH_ALL)
2843STEXI
2844@item -bt hci[...]
2845@findex -bt
2846Defines the function of the corresponding Bluetooth HCI.  -bt options
2847are matched with the HCIs present in the chosen machine type.  For
2848example when emulating a machine with only one HCI built into it, only
2849the first @code{-bt hci[...]} option is valid and defines the HCI's
2850logic.  The Transport Layer is decided by the machine type.  Currently
2851the machines @code{n800} and @code{n810} have one HCI and all other
2852machines have none.
2853
2854@anchor{bt-hcis}
2855The following three types are recognized:
2856
2857@table @option
2858@item -bt hci,null
2859(default) The corresponding Bluetooth HCI assumes no internal logic
2860and will not respond to any HCI commands or emit events.
2861
2862@item -bt hci,host[:@var{id}]
2863(@code{bluez} only) The corresponding HCI passes commands / events
2864to / from the physical HCI identified by the name @var{id} (default:
2865@code{hci0}) on the computer running QEMU.  Only available on @code{bluez}
2866capable systems like Linux.
2867
2868@item -bt hci[,vlan=@var{n}]
2869Add a virtual, standard HCI that will participate in the Bluetooth
2870scatternet @var{n} (default @code{0}).  Similarly to @option{-net}
2871VLANs, devices inside a bluetooth network @var{n} can only communicate
2872with other devices in the same network (scatternet).
2873@end table
2874
2875@item -bt vhci[,vlan=@var{n}]
2876(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2877to the host bluetooth stack instead of to the emulated target.  This
2878allows the host and target machines to participate in a common scatternet
2879and communicate.  Requires the Linux @code{vhci} driver installed.  Can
2880be used as following:
2881
2882@example
2883qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2884@end example
2885
2886@item -bt device:@var{dev}[,vlan=@var{n}]
2887Emulate a bluetooth device @var{dev} and place it in network @var{n}
2888(default @code{0}).  QEMU can only emulate one type of bluetooth devices
2889currently:
2890
2891@table @option
2892@item keyboard
2893Virtual wireless keyboard implementing the HIDP bluetooth profile.
2894@end table
2895ETEXI
2896
2897STEXI
2898@end table
2899ETEXI
2900DEFHEADING()
2901
2902#ifdef CONFIG_TPM
2903DEFHEADING(TPM device options:)
2904
2905DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2906    "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2907    "                use path to provide path to a character device; default is /dev/tpm0\n"
2908    "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2909    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n"
2910    "-tpmdev emulator,id=id,chardev=dev\n"
2911    "                configure the TPM device using chardev backend\n",
2912    QEMU_ARCH_ALL)
2913STEXI
2914
2915The general form of a TPM device option is:
2916@table @option
2917
2918@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2919@findex -tpmdev
2920
2921The specific backend type will determine the applicable options.
2922The @code{-tpmdev} option creates the TPM backend and requires a
2923@code{-device} option that specifies the TPM frontend interface model.
2924
2925Use @code{-tpmdev help} to print all available TPM backend types.
2926
2927@end table
2928
2929The available backends are:
2930
2931@table @option
2932
2933@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2934
2935(Linux-host only) Enable access to the host's TPM using the passthrough
2936driver.
2937
2938@option{path} specifies the path to the host's TPM device, i.e., on
2939a Linux host this would be @code{/dev/tpm0}.
2940@option{path} is optional and by default @code{/dev/tpm0} is used.
2941
2942@option{cancel-path} specifies the path to the host TPM device's sysfs
2943entry allowing for cancellation of an ongoing TPM command.
2944@option{cancel-path} is optional and by default QEMU will search for the
2945sysfs entry to use.
2946
2947Some notes about using the host's TPM with the passthrough driver:
2948
2949The TPM device accessed by the passthrough driver must not be
2950used by any other application on the host.
2951
2952Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2953the VM's firmware (BIOS/UEFI) will not be able to initialize the
2954TPM again and may therefore not show a TPM-specific menu that would
2955otherwise allow the user to configure the TPM, e.g., allow the user to
2956enable/disable or activate/deactivate the TPM.
2957Further, if TPM ownership is released from within a VM then the host's TPM
2958will get disabled and deactivated. To enable and activate the
2959TPM again afterwards, the host has to be rebooted and the user is
2960required to enter the firmware's menu to enable and activate the TPM.
2961If the TPM is left disabled and/or deactivated most TPM commands will fail.
2962
2963To create a passthrough TPM use the following two options:
2964@example
2965-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2966@end example
2967Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2968@code{tpmdev=tpm0} in the device option.
2969
2970@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
2971
2972(Linux-host only) Enable access to a TPM emulator using Unix domain socket based
2973chardev backend.
2974
2975@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
2976
2977To create a TPM emulator backend device with chardev socket backend:
2978@example
2979
2980-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
2981
2982@end example
2983
2984ETEXI
2985
2986STEXI
2987@end table
2988ETEXI
2989DEFHEADING()
2990
2991#endif
2992
2993DEFHEADING(Linux/Multiboot boot specific:)
2994STEXI
2995
2996When using these options, you can use a given Linux or Multiboot
2997kernel without installing it in the disk image. It can be useful
2998for easier testing of various kernels.
2999
3000@table @option
3001ETEXI
3002
3003DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
3004    "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
3005STEXI
3006@item -kernel @var{bzImage}
3007@findex -kernel
3008Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
3009or in multiboot format.
3010ETEXI
3011
3012DEF("append", HAS_ARG, QEMU_OPTION_append, \
3013    "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
3014STEXI
3015@item -append @var{cmdline}
3016@findex -append
3017Use @var{cmdline} as kernel command line
3018ETEXI
3019
3020DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
3021           "-initrd file    use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
3022STEXI
3023@item -initrd @var{file}
3024@findex -initrd
3025Use @var{file} as initial ram disk.
3026
3027@item -initrd "@var{file1} arg=foo,@var{file2}"
3028
3029This syntax is only available with multiboot.
3030
3031Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3032first module.
3033ETEXI
3034
3035DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
3036    "-dtb    file    use 'file' as device tree image\n", QEMU_ARCH_ALL)
3037STEXI
3038@item -dtb @var{file}
3039@findex -dtb
3040Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3041on boot.
3042ETEXI
3043
3044STEXI
3045@end table
3046ETEXI
3047DEFHEADING()
3048
3049DEFHEADING(Debug/Expert options:)
3050STEXI
3051@table @option
3052ETEXI
3053
3054DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
3055    "-fw_cfg [name=]<name>,file=<file>\n"
3056    "                add named fw_cfg entry with contents from file\n"
3057    "-fw_cfg [name=]<name>,string=<str>\n"
3058    "                add named fw_cfg entry with contents from string\n",
3059    QEMU_ARCH_ALL)
3060STEXI
3061
3062@item -fw_cfg [name=]@var{name},file=@var{file}
3063@findex -fw_cfg
3064Add named fw_cfg entry with contents from file @var{file}.
3065
3066@item -fw_cfg [name=]@var{name},string=@var{str}
3067Add named fw_cfg entry with contents from string @var{str}.
3068
3069The terminating NUL character of the contents of @var{str} will not be
3070included as part of the fw_cfg item data. To insert contents with
3071embedded NUL characters, you have to use the @var{file} parameter.
3072
3073The fw_cfg entries are passed by QEMU through to the guest.
3074
3075Example:
3076@example
3077    -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3078@end example
3079creates an fw_cfg entry named opt/com.mycompany/blob with contents
3080from ./my_blob.bin.
3081
3082ETEXI
3083
3084DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
3085    "-serial dev     redirect the serial port to char device 'dev'\n",
3086    QEMU_ARCH_ALL)
3087STEXI
3088@item -serial @var{dev}
3089@findex -serial
3090Redirect the virtual serial port to host character device
3091@var{dev}. The default device is @code{vc} in graphical mode and
3092@code{stdio} in non graphical mode.
3093
3094This option can be used several times to simulate up to 4 serial
3095ports.
3096
3097Use @code{-serial none} to disable all serial ports.
3098
3099Available character devices are:
3100@table @option
3101@item vc[:@var{W}x@var{H}]
3102Virtual console. Optionally, a width and height can be given in pixel with
3103@example
3104vc:800x600
3105@end example
3106It is also possible to specify width or height in characters:
3107@example
3108vc:80Cx24C
3109@end example
3110@item pty
3111[Linux only] Pseudo TTY (a new PTY is automatically allocated)
3112@item none
3113No device is allocated.
3114@item null
3115void device
3116@item chardev:@var{id}
3117Use a named character device defined with the @code{-chardev} option.
3118@item /dev/XXX
3119[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3120parameters are set according to the emulated ones.
3121@item /dev/parport@var{N}
3122[Linux only, parallel port only] Use host parallel port
3123@var{N}. Currently SPP and EPP parallel port features can be used.
3124@item file:@var{filename}
3125Write output to @var{filename}. No character can be read.
3126@item stdio
3127[Unix only] standard input/output
3128@item pipe:@var{filename}
3129name pipe @var{filename}
3130@item COM@var{n}
3131[Windows only] Use host serial port @var{n}
3132@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3133This implements UDP Net Console.
3134When @var{remote_host} or @var{src_ip} are not specified
3135they default to @code{0.0.0.0}.
3136When not using a specified @var{src_port} a random port is automatically chosen.
3137
3138If you just want a simple readonly console you can use @code{netcat} or
3139@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3140@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3141will appear in the netconsole session.
3142
3143If you plan to send characters back via netconsole or you want to stop
3144and start QEMU a lot of times, you should have QEMU use the same
3145source port each time by using something like @code{-serial
3146udp::4555@@:4556} to QEMU. Another approach is to use a patched
3147version of netcat which can listen to a TCP port and send and receive
3148characters via udp.  If you have a patched version of netcat which
3149activates telnet remote echo and single char transfer, then you can
3150use the following options to set up a netcat redirector to allow
3151telnet on port 5555 to access the QEMU port.
3152@table @code
3153@item QEMU Options:
3154-serial udp::4555@@:4556
3155@item netcat options:
3156-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3157@item telnet options:
3158localhost 5555
3159@end table
3160
3161@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3162The TCP Net Console has two modes of operation.  It can send the serial
3163I/O to a location or wait for a connection from a location.  By default
3164the TCP Net Console is sent to @var{host} at the @var{port}.  If you use
3165the @var{server} option QEMU will wait for a client socket application
3166to connect to the port before continuing, unless the @code{nowait}
3167option was specified.  The @code{nodelay} option disables the Nagle buffering
3168algorithm.  The @code{reconnect} option only applies if @var{noserver} is
3169set, if the connection goes down it will attempt to reconnect at the
3170given interval.  If @var{host} is omitted, 0.0.0.0 is assumed. Only
3171one TCP connection at a time is accepted. You can use @code{telnet} to
3172connect to the corresponding character device.
3173@table @code
3174@item Example to send tcp console to 192.168.0.2 port 4444
3175-serial tcp:192.168.0.2:4444
3176@item Example to listen and wait on port 4444 for connection
3177-serial tcp::4444,server
3178@item Example to not wait and listen on ip 192.168.0.100 port 4444
3179-serial tcp:192.168.0.100:4444,server,nowait
3180@end table
3181
3182@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3183The telnet protocol is used instead of raw tcp sockets.  The options
3184work the same as if you had specified @code{-serial tcp}.  The
3185difference is that the port acts like a telnet server or client using
3186telnet option negotiation.  This will also allow you to send the
3187MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3188sequence.  Typically in unix telnet you do it with Control-] and then
3189type "send break" followed by pressing the enter key.
3190
3191@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3192A unix domain socket is used instead of a tcp socket.  The option works the
3193same as if you had specified @code{-serial tcp} except the unix domain socket
3194@var{path} is used for connections.
3195
3196@item mon:@var{dev_string}
3197This is a special option to allow the monitor to be multiplexed onto
3198another serial port.  The monitor is accessed with key sequence of
3199@key{Control-a} and then pressing @key{c}.
3200@var{dev_string} should be any one of the serial devices specified
3201above.  An example to multiplex the monitor onto a telnet server
3202listening on port 4444 would be:
3203@table @code
3204@item -serial mon:telnet::4444,server,nowait
3205@end table
3206When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3207QEMU any more but will be passed to the guest instead.
3208
3209@item braille
3210Braille device.  This will use BrlAPI to display the braille output on a real
3211or fake device.
3212
3213@item msmouse
3214Three button serial mouse. Configure the guest to use Microsoft protocol.
3215@end table
3216ETEXI
3217
3218DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3219    "-parallel dev   redirect the parallel port to char device 'dev'\n",
3220    QEMU_ARCH_ALL)
3221STEXI
3222@item -parallel @var{dev}
3223@findex -parallel
3224Redirect the virtual parallel port to host device @var{dev} (same
3225devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3226be used to use hardware devices connected on the corresponding host
3227parallel port.
3228
3229This option can be used several times to simulate up to 3 parallel
3230ports.
3231
3232Use @code{-parallel none} to disable all parallel ports.
3233ETEXI
3234
3235DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3236    "-monitor dev    redirect the monitor to char device 'dev'\n",
3237    QEMU_ARCH_ALL)
3238STEXI
3239@item -monitor @var{dev}
3240@findex -monitor
3241Redirect the monitor to host device @var{dev} (same devices as the
3242serial port).
3243The default device is @code{vc} in graphical mode and @code{stdio} in
3244non graphical mode.
3245Use @code{-monitor none} to disable the default monitor.
3246ETEXI
3247DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3248    "-qmp dev        like -monitor but opens in 'control' mode\n",
3249    QEMU_ARCH_ALL)
3250STEXI
3251@item -qmp @var{dev}
3252@findex -qmp
3253Like -monitor but opens in 'control' mode.
3254ETEXI
3255DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3256    "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3257    QEMU_ARCH_ALL)
3258STEXI
3259@item -qmp-pretty @var{dev}
3260@findex -qmp-pretty
3261Like -qmp but uses pretty JSON formatting.
3262ETEXI
3263
3264DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3265    "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL)
3266STEXI
3267@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]
3268@findex -mon
3269Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing
3270easing human reading and debugging.
3271ETEXI
3272
3273DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3274    "-debugcon dev   redirect the debug console to char device 'dev'\n",
3275    QEMU_ARCH_ALL)
3276STEXI
3277@item -debugcon @var{dev}
3278@findex -debugcon
3279Redirect the debug console to host device @var{dev} (same devices as the
3280serial port).  The debug console is an I/O port which is typically port
32810xe9; writing to that I/O port sends output to this device.
3282The default device is @code{vc} in graphical mode and @code{stdio} in
3283non graphical mode.
3284ETEXI
3285
3286DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3287    "-pidfile file   write PID to 'file'\n", QEMU_ARCH_ALL)
3288STEXI
3289@item -pidfile @var{file}
3290@findex -pidfile
3291Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3292from a script.
3293ETEXI
3294
3295DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3296    "-singlestep     always run in singlestep mode\n", QEMU_ARCH_ALL)
3297STEXI
3298@item -singlestep
3299@findex -singlestep
3300Run the emulation in single step mode.
3301ETEXI
3302
3303DEF("S", 0, QEMU_OPTION_S, \
3304    "-S              freeze CPU at startup (use 'c' to start execution)\n",
3305    QEMU_ARCH_ALL)
3306STEXI
3307@item -S
3308@findex -S
3309Do not start CPU at startup (you must type 'c' in the monitor).
3310ETEXI
3311
3312DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3313    "-realtime [mlock=on|off]\n"
3314    "                run qemu with realtime features\n"
3315    "                mlock=on|off controls mlock support (default: on)\n",
3316    QEMU_ARCH_ALL)
3317STEXI
3318@item -realtime mlock=on|off
3319@findex -realtime
3320Run qemu with realtime features.
3321mlocking qemu and guest memory can be enabled via @option{mlock=on}
3322(enabled by default).
3323ETEXI
3324
3325DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3326    "-gdb dev        wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3327STEXI
3328@item -gdb @var{dev}
3329@findex -gdb
3330Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3331connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3332stdio are reasonable use case. The latter is allowing to start QEMU from
3333within gdb and establish the connection via a pipe:
3334@example
3335(gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3336@end example
3337ETEXI
3338
3339DEF("s", 0, QEMU_OPTION_s, \
3340    "-s              shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3341    QEMU_ARCH_ALL)
3342STEXI
3343@item -s
3344@findex -s
3345Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3346(@pxref{gdb_usage}).
3347ETEXI
3348
3349DEF("d", HAS_ARG, QEMU_OPTION_d, \
3350    "-d item1,...    enable logging of specified items (use '-d help' for a list of log items)\n",
3351    QEMU_ARCH_ALL)
3352STEXI
3353@item -d @var{item1}[,...]
3354@findex -d
3355Enable logging of specified items. Use '-d help' for a list of log items.
3356ETEXI
3357
3358DEF("D", HAS_ARG, QEMU_OPTION_D, \
3359    "-D logfile      output log to logfile (default stderr)\n",
3360    QEMU_ARCH_ALL)
3361STEXI
3362@item -D @var{logfile}
3363@findex -D
3364Output log in @var{logfile} instead of to stderr
3365ETEXI
3366
3367DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3368    "-dfilter range,..  filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3369    QEMU_ARCH_ALL)
3370STEXI
3371@item -dfilter @var{range1}[,...]
3372@findex -dfilter
3373Filter debug output to that relevant to a range of target addresses. The filter
3374spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3375@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3376addresses and sizes required. For example:
3377@example
3378    -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3379@end example
3380Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3381the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3382block starting at 0xffffffc00005f000.
3383ETEXI
3384
3385DEF("L", HAS_ARG, QEMU_OPTION_L, \
3386    "-L path         set the directory for the BIOS, VGA BIOS and keymaps\n",
3387    QEMU_ARCH_ALL)
3388STEXI
3389@item -L  @var{path}
3390@findex -L
3391Set the directory for the BIOS, VGA BIOS and keymaps.
3392
3393To list all the data directories, use @code{-L help}.
3394ETEXI
3395
3396DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3397    "-bios file      set the filename for the BIOS\n", QEMU_ARCH_ALL)
3398STEXI
3399@item -bios @var{file}
3400@findex -bios
3401Set the filename for the BIOS.
3402ETEXI
3403
3404DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3405    "-enable-kvm     enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3406STEXI
3407@item -enable-kvm
3408@findex -enable-kvm
3409Enable KVM full virtualization support. This option is only available
3410if KVM support is enabled when compiling.
3411ETEXI
3412
3413DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3414    "-enable-hax     enable HAX virtualization support\n", QEMU_ARCH_I386)
3415STEXI
3416@item -enable-hax
3417@findex -enable-hax
3418Enable HAX (Hardware-based Acceleration eXecution) support. This option
3419is only available if HAX support is enabled when compiling. HAX is only
3420applicable to MAC and Windows platform, and thus does not conflict with
3421KVM.
3422ETEXI
3423
3424DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3425    "-xen-domid id   specify xen guest domain id\n", QEMU_ARCH_ALL)
3426DEF("xen-create", 0, QEMU_OPTION_xen_create,
3427    "-xen-create     create domain using xen hypercalls, bypassing xend\n"
3428    "                warning: should not be used when xend is in use\n",
3429    QEMU_ARCH_ALL)
3430DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3431    "-xen-attach     attach to existing xen domain\n"
3432    "                xend will use this when starting QEMU\n",
3433    QEMU_ARCH_ALL)
3434DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
3435    "-xen-domid-restrict     restrict set of available xen operations\n"
3436    "                        to specified domain id. (Does not affect\n"
3437    "                        xenpv machine type).\n",
3438    QEMU_ARCH_ALL)
3439STEXI
3440@item -xen-domid @var{id}
3441@findex -xen-domid
3442Specify xen guest domain @var{id} (XEN only).
3443@item -xen-create
3444@findex -xen-create
3445Create domain using xen hypercalls, bypassing xend.
3446Warning: should not be used when xend is in use (XEN only).
3447@item -xen-attach
3448@findex -xen-attach
3449Attach to existing xen domain.
3450xend will use this when starting QEMU (XEN only).
3451@findex -xen-domid-restrict
3452Restrict set of available xen operations to specified domain id (XEN only).
3453ETEXI
3454
3455DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3456    "-no-reboot      exit instead of rebooting\n", QEMU_ARCH_ALL)
3457STEXI
3458@item -no-reboot
3459@findex -no-reboot
3460Exit instead of rebooting.
3461ETEXI
3462
3463DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3464    "-no-shutdown    stop before shutdown\n", QEMU_ARCH_ALL)
3465STEXI
3466@item -no-shutdown
3467@findex -no-shutdown
3468Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3469This allows for instance switching to monitor to commit changes to the
3470disk image.
3471ETEXI
3472
3473DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3474    "-loadvm [tag|id]\n" \
3475    "                start right away with a saved state (loadvm in monitor)\n",
3476    QEMU_ARCH_ALL)
3477STEXI
3478@item -loadvm @var{file}
3479@findex -loadvm
3480Start right away with a saved state (@code{loadvm} in monitor)
3481ETEXI
3482
3483#ifndef _WIN32
3484DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3485    "-daemonize      daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3486#endif
3487STEXI
3488@item -daemonize
3489@findex -daemonize
3490Daemonize the QEMU process after initialization.  QEMU will not detach from
3491standard IO until it is ready to receive connections on any of its devices.
3492This option is a useful way for external programs to launch QEMU without having
3493to cope with initialization race conditions.
3494ETEXI
3495
3496DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3497    "-option-rom rom load a file, rom, into the option ROM space\n",
3498    QEMU_ARCH_ALL)
3499STEXI
3500@item -option-rom @var{file}
3501@findex -option-rom
3502Load the contents of @var{file} as an option ROM.
3503This option is useful to load things like EtherBoot.
3504ETEXI
3505
3506HXCOMM Silently ignored for compatibility
3507DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3508
3509HXCOMM Options deprecated by -rtc
3510DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3511DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3512
3513DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3514    "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3515    "                set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3516    QEMU_ARCH_ALL)
3517
3518STEXI
3519
3520@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3521@findex -rtc
3522Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3523UTC or local time, respectively. @code{localtime} is required for correct date in
3524MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3525format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3526
3527By default the RTC is driven by the host system time. This allows using of the
3528RTC as accurate reference clock inside the guest, specifically if the host
3529time is smoothly following an accurate external reference clock, e.g. via NTP.
3530If you want to isolate the guest time from the host, you can set @option{clock}
3531to @code{rt} instead.  To even prevent it from progressing during suspension,
3532you can set it to @code{vm}.
3533
3534Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3535specifically with Windows' ACPI HAL. This option will try to figure out how
3536many timer interrupts were not processed by the Windows guest and will
3537re-inject them.
3538ETEXI
3539
3540DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3541    "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3542    "                enable virtual instruction counter with 2^N clock ticks per\n" \
3543    "                instruction, enable aligning the host and virtual clocks\n" \
3544    "                or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3545STEXI
3546@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3547@findex -icount
3548Enable virtual instruction counter.  The virtual cpu will execute one
3549instruction every 2^@var{N} ns of virtual time.  If @code{auto} is specified
3550then the virtual cpu speed will be automatically adjusted to keep virtual
3551time within a few seconds of real time.
3552
3553When the virtual cpu is sleeping, the virtual time will advance at default
3554speed unless @option{sleep=on|off} is specified.
3555With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3556instantly whenever the virtual cpu goes to sleep mode and will not advance
3557if no timer is enabled. This behavior give deterministic execution times from
3558the guest point of view.
3559
3560Note that while this option can give deterministic behavior, it does not
3561provide cycle accurate emulation.  Modern CPUs contain superscalar out of
3562order cores with complex cache hierarchies.  The number of instructions
3563executed often has little or no correlation with actual performance.
3564
3565@option{align=on} will activate the delay algorithm which will try
3566to synchronise the host clock and the virtual clock. The goal is to
3567have a guest running at the real frequency imposed by the shift option.
3568Whenever the guest clock is behind the host clock and if
3569@option{align=on} is specified then we print a message to the user
3570to inform about the delay.
3571Currently this option does not work when @option{shift} is @code{auto}.
3572Note: The sync algorithm will work for those shift values for which
3573the guest clock runs ahead of the host clock. Typically this happens
3574when the shift value is high (how high depends on the host machine).
3575
3576When @option{rr} option is specified deterministic record/replay is enabled.
3577Replay log is written into @var{filename} file in record mode and
3578read from this file in replay mode.
3579
3580Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3581at the start of execution recording. In replay mode this option is used
3582to load the initial VM state.
3583ETEXI
3584
3585DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3586    "-watchdog model\n" \
3587    "                enable virtual hardware watchdog [default=none]\n",
3588    QEMU_ARCH_ALL)
3589STEXI
3590@item -watchdog @var{model}
3591@findex -watchdog
3592Create a virtual hardware watchdog device.  Once enabled (by a guest
3593action), the watchdog must be periodically polled by an agent inside
3594the guest or else the guest will be restarted. Choose a model for
3595which your guest has drivers.
3596
3597The @var{model} is the model of hardware watchdog to emulate. Use
3598@code{-watchdog help} to list available hardware models. Only one
3599watchdog can be enabled for a guest.
3600
3601The following models may be available:
3602@table @option
3603@item ib700
3604iBASE 700 is a very simple ISA watchdog with a single timer.
3605@item i6300esb
3606Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3607dual-timer watchdog.
3608@item diag288
3609A virtual watchdog for s390x backed by the diagnose 288 hypercall
3610(currently KVM only).
3611@end table
3612ETEXI
3613
3614DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3615    "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \
3616    "                action when watchdog fires [default=reset]\n",
3617    QEMU_ARCH_ALL)
3618STEXI
3619@item -watchdog-action @var{action}
3620@findex -watchdog-action
3621
3622The @var{action} controls what QEMU will do when the watchdog timer
3623expires.
3624The default is
3625@code{reset} (forcefully reset the guest).
3626Other possible actions are:
3627@code{shutdown} (attempt to gracefully shutdown the guest),
3628@code{poweroff} (forcefully poweroff the guest),
3629@code{inject-nmi} (inject a NMI into the guest),
3630@code{pause} (pause the guest),
3631@code{debug} (print a debug message and continue), or
3632@code{none} (do nothing).
3633
3634Note that the @code{shutdown} action requires that the guest responds
3635to ACPI signals, which it may not be able to do in the sort of
3636situations where the watchdog would have expired, and thus
3637@code{-watchdog-action shutdown} is not recommended for production use.
3638
3639Examples:
3640
3641@table @code
3642@item -watchdog i6300esb -watchdog-action pause
3643@itemx -watchdog ib700
3644@end table
3645ETEXI
3646
3647DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3648    "-echr chr       set terminal escape character instead of ctrl-a\n",
3649    QEMU_ARCH_ALL)
3650STEXI
3651
3652@item -echr @var{numeric_ascii_value}
3653@findex -echr
3654Change the escape character used for switching to the monitor when using
3655monitor and serial sharing.  The default is @code{0x01} when using the
3656@code{-nographic} option.  @code{0x01} is equal to pressing
3657@code{Control-a}.  You can select a different character from the ascii
3658control keys where 1 through 26 map to Control-a through Control-z.  For
3659instance you could use the either of the following to change the escape
3660character to Control-t.
3661@table @code
3662@item -echr 0x14
3663@itemx -echr 20
3664@end table
3665ETEXI
3666
3667DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3668    "-virtioconsole c\n" \
3669    "                set virtio console\n", QEMU_ARCH_ALL)
3670STEXI
3671@item -virtioconsole @var{c}
3672@findex -virtioconsole
3673Set virtio console.
3674
3675This option is maintained for backward compatibility.
3676
3677Please use @code{-device virtconsole} for the new way of invocation.
3678ETEXI
3679
3680DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3681    "-show-cursor    show cursor\n", QEMU_ARCH_ALL)
3682STEXI
3683@item -show-cursor
3684@findex -show-cursor
3685Show cursor.
3686ETEXI
3687
3688DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3689    "-tb-size n      set TB size\n", QEMU_ARCH_ALL)
3690STEXI
3691@item -tb-size @var{n}
3692@findex -tb-size
3693Set TB size.
3694ETEXI
3695
3696DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3697    "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3698    "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3699    "-incoming unix:socketpath\n" \
3700    "                prepare for incoming migration, listen on\n" \
3701    "                specified protocol and socket address\n" \
3702    "-incoming fd:fd\n" \
3703    "-incoming exec:cmdline\n" \
3704    "                accept incoming migration on given file descriptor\n" \
3705    "                or from given external command\n" \
3706    "-incoming defer\n" \
3707    "                wait for the URI to be specified via migrate_incoming\n",
3708    QEMU_ARCH_ALL)
3709STEXI
3710@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3711@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3712@findex -incoming
3713Prepare for incoming migration, listen on a given tcp port.
3714
3715@item -incoming unix:@var{socketpath}
3716Prepare for incoming migration, listen on a given unix socket.
3717
3718@item -incoming fd:@var{fd}
3719Accept incoming migration from a given filedescriptor.
3720
3721@item -incoming exec:@var{cmdline}
3722Accept incoming migration as an output from specified external command.
3723
3724@item -incoming defer
3725Wait for the URI to be specified via migrate_incoming.  The monitor can
3726be used to change settings (such as migration parameters) prior to issuing
3727the migrate_incoming to allow the migration to begin.
3728ETEXI
3729
3730DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \
3731    "-only-migratable     allow only migratable devices\n", QEMU_ARCH_ALL)
3732STEXI
3733@item -only-migratable
3734@findex -only-migratable
3735Only allow migratable devices. Devices will not be allowed to enter an
3736unmigratable state.
3737ETEXI
3738
3739DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3740    "-nodefaults     don't create default devices\n", QEMU_ARCH_ALL)
3741STEXI
3742@item -nodefaults
3743@findex -nodefaults
3744Don't create default devices. Normally, QEMU sets the default devices like serial
3745port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3746CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3747default devices.
3748ETEXI
3749
3750#ifndef _WIN32
3751DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3752    "-chroot dir     chroot to dir just before starting the VM\n",
3753    QEMU_ARCH_ALL)
3754#endif
3755STEXI
3756@item -chroot @var{dir}
3757@findex -chroot
3758Immediately before starting guest execution, chroot to the specified
3759directory.  Especially useful in combination with -runas.
3760ETEXI
3761
3762#ifndef _WIN32
3763DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3764    "-runas user     change to user id user just before starting the VM\n",
3765    QEMU_ARCH_ALL)
3766#endif
3767STEXI
3768@item -runas @var{user}
3769@findex -runas
3770Immediately before starting guest execution, drop root privileges, switching
3771to the specified user.
3772ETEXI
3773
3774DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3775    "-prom-env variable=value\n"
3776    "                set OpenBIOS nvram variables\n",
3777    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3778STEXI
3779@item -prom-env @var{variable}=@var{value}
3780@findex -prom-env
3781Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3782ETEXI
3783DEF("semihosting", 0, QEMU_OPTION_semihosting,
3784    "-semihosting    semihosting mode\n",
3785    QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3786    QEMU_ARCH_MIPS)
3787STEXI
3788@item -semihosting
3789@findex -semihosting
3790Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3791ETEXI
3792DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3793    "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3794    "                semihosting configuration\n",
3795QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3796QEMU_ARCH_MIPS)
3797STEXI
3798@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3799@findex -semihosting-config
3800Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3801@table @option
3802@item target=@code{native|gdb|auto}
3803Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3804or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3805during debug sessions and @code{native} otherwise.
3806@item arg=@var{str1},arg=@var{str2},...
3807Allows the user to pass input arguments, and can be used multiple times to build
3808up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3809command line is still supported for backward compatibility. If both the
3810@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3811specified, the former is passed to semihosting as it always takes precedence.
3812@end table
3813ETEXI
3814DEF("old-param", 0, QEMU_OPTION_old_param,
3815    "-old-param      old param mode\n", QEMU_ARCH_ARM)
3816STEXI
3817@item -old-param
3818@findex -old-param (ARM)
3819Old param mode (ARM only).
3820ETEXI
3821
3822DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3823    "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
3824    "          [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
3825    "                Enable seccomp mode 2 system call filter (default 'off').\n" \
3826    "                use 'obsolete' to allow obsolete system calls that are provided\n" \
3827    "                    by the kernel, but typically no longer used by modern\n" \
3828    "                    C library implementations.\n" \
3829    "                use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \
3830    "                    its privileges by blacklisting all set*uid|gid system calls.\n" \
3831    "                    The value 'children' will deny set*uid|gid system calls for\n" \
3832    "                    main QEMU process but will allow forks and execves to run unprivileged\n" \
3833    "                use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \
3834    "                     blacklisting *fork and execve\n" \
3835    "                use 'resourcecontrol' to disable process affinity and schedular priority\n",
3836    QEMU_ARCH_ALL)
3837STEXI
3838@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
3839@findex -sandbox
3840Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3841disable it.  The default is 'off'.
3842@table @option
3843@item obsolete=@var{string}
3844Enable Obsolete system calls
3845@item elevateprivileges=@var{string}
3846Disable set*uid|gid system calls
3847@item spawn=@var{string}
3848Disable *fork and execve
3849@item resourcecontrol=@var{string}
3850Disable process affinity and schedular priority
3851@end table
3852ETEXI
3853
3854DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3855    "-readconfig <file>\n", QEMU_ARCH_ALL)
3856STEXI
3857@item -readconfig @var{file}
3858@findex -readconfig
3859Read device configuration from @var{file}. This approach is useful when you want to spawn
3860QEMU process with many command line options but you don't want to exceed the command line
3861character limit.
3862ETEXI
3863DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3864    "-writeconfig <file>\n"
3865    "                read/write config file\n", QEMU_ARCH_ALL)
3866STEXI
3867@item -writeconfig @var{file}
3868@findex -writeconfig
3869Write device configuration to @var{file}. The @var{file} can be either filename to save
3870command line and device configuration into file or dash @code{-}) character to print the
3871output to stdout. This can be later used as input file for @code{-readconfig} option.
3872ETEXI
3873HXCOMM Deprecated, same as -no-user-config
3874DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
3875DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3876    "-no-user-config\n"
3877    "                do not load default user-provided config files at startup\n",
3878    QEMU_ARCH_ALL)
3879STEXI
3880@item -no-user-config
3881@findex -no-user-config
3882The @code{-no-user-config} option makes QEMU not load any of the user-provided
3883config files on @var{sysconfdir}.
3884ETEXI
3885DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3886    "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3887    "                specify tracing options\n",
3888    QEMU_ARCH_ALL)
3889STEXI
3890HXCOMM This line is not accurate, as some sub-options are backend-specific but
3891HXCOMM HX does not support conditional compilation of text.
3892@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
3893@findex -trace
3894@include qemu-option-trace.texi
3895ETEXI
3896
3897HXCOMM Internal use
3898DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3899DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3900
3901#ifdef __linux__
3902DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3903    "-enable-fips    enable FIPS 140-2 compliance\n",
3904    QEMU_ARCH_ALL)
3905#endif
3906STEXI
3907@item -enable-fips
3908@findex -enable-fips
3909Enable FIPS 140-2 compliance mode.
3910ETEXI
3911
3912HXCOMM Deprecated by -machine accel=tcg property
3913DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3914
3915HXCOMM Deprecated by kvm-pit driver properties
3916DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3917    "", QEMU_ARCH_I386)
3918
3919HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3920DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3921
3922HXCOMM Deprecated (ignored)
3923DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3924
3925DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3926    "-msg timestamp[=on|off]\n"
3927    "                change the format of messages\n"
3928    "                on|off controls leading timestamps (default:on)\n",
3929    QEMU_ARCH_ALL)
3930STEXI
3931@item -msg timestamp[=on|off]
3932@findex -msg
3933prepend a timestamp to each log message.(default:on)
3934ETEXI
3935
3936DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3937    "-dump-vmstate <file>\n"
3938    "                Output vmstate information in JSON format to file.\n"
3939    "                Use the scripts/vmstate-static-checker.py file to\n"
3940    "                check for possible regressions in migration code\n"
3941    "                by comparing two such vmstate dumps.\n",
3942    QEMU_ARCH_ALL)
3943STEXI
3944@item -dump-vmstate @var{file}
3945@findex -dump-vmstate
3946Dump json-encoded vmstate information for current machine type to file
3947in @var{file}
3948ETEXI
3949
3950STEXI
3951@end table
3952ETEXI
3953DEFHEADING()
3954
3955DEFHEADING(Generic object creation:)
3956STEXI
3957@table @option
3958ETEXI
3959
3960DEF("object", HAS_ARG, QEMU_OPTION_object,
3961    "-object TYPENAME[,PROP1=VALUE1,...]\n"
3962    "                create a new object of type TYPENAME setting properties\n"
3963    "                in the order they are specified.  Note that the 'id'\n"
3964    "                property must be set.  These objects are placed in the\n"
3965    "                '/objects' path.\n",
3966    QEMU_ARCH_ALL)
3967STEXI
3968@item -object @var{typename}[,@var{prop1}=@var{value1},...]
3969@findex -object
3970Create a new object of type @var{typename} setting properties
3971in the order they are specified.  Note that the 'id'
3972property must be set.  These objects are placed in the
3973'/objects' path.
3974
3975@table @option
3976
3977@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}
3978
3979Creates a memory file backend object, which can be used to back
3980the guest RAM with huge pages.
3981
3982The @option{id} parameter is a unique ID that will be used to reference this
3983memory region when configuring the @option{-numa} argument.
3984
3985The @option{size} option provides the size of the memory region, and accepts
3986common suffixes, eg @option{500M}.
3987
3988The @option{mem-path} provides the path to either a shared memory or huge page
3989filesystem mount.
3990
3991The @option{share} boolean option determines whether the memory
3992region is marked as private to QEMU, or shared. The latter allows
3993a co-operating external process to access the QEMU memory region.
3994
3995Setting the @option{discard-data} boolean option to @var{on}
3996indicates that file contents can be destroyed when QEMU exits,
3997to avoid unnecessarily flushing data to the backing file.  Note
3998that @option{discard-data} is only an optimization, and QEMU
3999might not discard file contents if it aborts unexpectedly or is
4000terminated using SIGKILL.
4001
4002The @option{merge} boolean option enables memory merge, also known as
4003MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for
4004memory deduplication.
4005
4006Setting the @option{dump} boolean option to @var{off} excludes the memory from
4007core dumps. This feature is also known as MADV_DONTDUMP.
4008
4009The @option{prealloc} boolean option enables memory preallocation.
4010
4011The @option{host-nodes} option binds the memory range to a list of NUMA host
4012nodes.
4013
4014The @option{policy} option sets the NUMA policy to one of the following values:
4015
4016@table @option
4017@item @var{default}
4018default host policy
4019
4020@item @var{preferred}
4021prefer the given host node list for allocation
4022
4023@item @var{bind}
4024restrict memory allocation to the given host node list
4025
4026@item @var{interleave}
4027interleave memory allocations across the given host node list
4028@end table
4029
4030The @option{align} option specifies the base address alignment when
4031QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg
4032@option{2M}. Some backend store specified by @option{mem-path}
4033requires an alignment different than the default one used by QEMU, eg
4034the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In
4035such cases, users can specify the required alignment via this option.
4036
4037@item -object memory-backend-ram,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}
4038
4039Creates a memory backend object, which can be used to back the guest RAM.
4040Memory backend objects offer more control than the @option{-m} option that is
4041traditionally used to define guest RAM. Please refer to
4042@option{memory-backend-file} for a description of the options.
4043
4044@item -object rng-random,id=@var{id},filename=@var{/dev/random}
4045
4046Creates a random number generator backend which obtains entropy from
4047a device on the host. The @option{id} parameter is a unique ID that
4048will be used to reference this entropy backend from the @option{virtio-rng}
4049device. The @option{filename} parameter specifies which file to obtain
4050entropy from and if omitted defaults to @option{/dev/random}.
4051
4052@item -object rng-egd,id=@var{id},chardev=@var{chardevid}
4053
4054Creates a random number generator backend which obtains entropy from
4055an external daemon running on the host. The @option{id} parameter is
4056a unique ID that will be used to reference this entropy backend from
4057the @option{virtio-rng} device. The @option{chardev} parameter is
4058the unique ID of a character device backend that provides the connection
4059to the RNG daemon.
4060
4061@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
4062
4063Creates a TLS anonymous credentials object, which can be used to provide
4064TLS support on network backends. The @option{id} parameter is a unique
4065ID which network backends will use to access the credentials. The
4066@option{endpoint} is either @option{server} or @option{client} depending
4067on whether the QEMU network backend that uses the credentials will be
4068acting as a client or as a server. If @option{verify-peer} is enabled
4069(the default) then once the handshake is completed, the peer credentials
4070will be verified, though this is a no-op for anonymous credentials.
4071
4072The @var{dir} parameter tells QEMU where to find the credential
4073files. For server endpoints, this directory may contain a file
4074@var{dh-params.pem} providing diffie-hellman parameters to use
4075for the TLS server. If the file is missing, QEMU will generate
4076a set of DH parameters at startup. This is a computationally
4077expensive operation that consumes random pool entropy, so it is
4078recommended that a persistent set of parameters be generated
4079upfront and saved.
4080
4081@item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off},passwordid=@var{id}
4082
4083Creates a TLS anonymous credentials object, which can be used to provide
4084TLS support on network backends. The @option{id} parameter is a unique
4085ID which network backends will use to access the credentials. The
4086@option{endpoint} is either @option{server} or @option{client} depending
4087on whether the QEMU network backend that uses the credentials will be
4088acting as a client or as a server. If @option{verify-peer} is enabled
4089(the default) then once the handshake is completed, the peer credentials
4090will be verified. With x509 certificates, this implies that the clients
4091must be provided with valid client certificates too.
4092
4093The @var{dir} parameter tells QEMU where to find the credential
4094files. For server endpoints, this directory may contain a file
4095@var{dh-params.pem} providing diffie-hellman parameters to use
4096for the TLS server. If the file is missing, QEMU will generate
4097a set of DH parameters at startup. This is a computationally
4098expensive operation that consumes random pool entropy, so it is
4099recommended that a persistent set of parameters be generated
4100upfront and saved.
4101
4102For x509 certificate credentials the directory will contain further files
4103providing the x509 certificates. The certificates must be stored
4104in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
4105@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
4106@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
4107
4108For the @var{server-key.pem} and @var{client-key.pem} files which
4109contain sensitive private keys, it is possible to use an encrypted
4110version by providing the @var{passwordid} parameter. This provides
4111the ID of a previously created @code{secret} object containing the
4112password for decryption.
4113
4114@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
4115
4116Interval @var{t} can't be 0, this filter batches the packet delivery: all
4117packets arriving in a given interval on netdev @var{netdevid} are delayed
4118until the end of the interval. Interval is in microseconds.
4119@option{status} is optional that indicate whether the netfilter is
4120on (enabled) or off (disabled), the default status for netfilter will be 'on'.
4121
4122queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4123
4124@option{all}: the filter is attached both to the receive and the transmit
4125              queue of the netdev (default).
4126
4127@option{rx}: the filter is attached to the receive queue of the netdev,
4128             where it will receive packets sent to the netdev.
4129
4130@option{tx}: the filter is attached to the transmit queue of the netdev,
4131             where it will receive packets sent by the netdev.
4132
4133@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4134
4135filter-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.
4136
4137@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4138
4139filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4140@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
4141filter-redirector will redirect packet with vnet_hdr_len.
4142Create a filter-redirector we need to differ outdev id from indev id, id can not
4143be the same. we can just use indev or outdev, but at least one of indev or outdev
4144need to be specified.
4145
4146@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4147
4148Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4149secondary from primary to keep secondary tcp connection,and rewrite
4150tcp packet to primary from secondary make tcp packet can be handled by
4151client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4152
4153usage:
4154colo secondary:
4155-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4156-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4157-object filter-rewriter,id=rew0,netdev=hn0,queue=all
4158
4159@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4160
4161Dump the network traffic on netdev @var{dev} to the file specified by
4162@var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4163The file format is libpcap, so it can be analyzed with tools such as tcpdump
4164or Wireshark.
4165
4166@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4167
4168Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4169secondary packet. If the packets are same, we will output primary
4170packet to outdev@var{chardevid}, else we will notify colo-frame
4171do checkpoint and send primary packet to outdev@var{chardevid}.
4172if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4173
4174we must use it with the help of filter-mirror and filter-redirector.
4175
4176@example
4177
4178primary:
4179-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4180-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4181-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4182-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4183-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4184-chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4185-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4186-chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4187-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4188-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4189-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4190-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4191
4192secondary:
4193-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4194-device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4195-chardev socket,id=red0,host=3.3.3.3,port=9003
4196-chardev socket,id=red1,host=3.3.3.3,port=9004
4197-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4198-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4199
4200@end example
4201
4202If you want to know the detail of above command line, you can read
4203the colo-compare git log.
4204
4205@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4206
4207Creates a cryptodev backend which executes crypto opreation from
4208the QEMU cipher APIS. The @var{id} parameter is
4209a unique ID that will be used to reference this cryptodev backend from
4210the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4211which specify the queue number of cryptodev backend, the default of
4212@var{queues} is 1.
4213
4214@example
4215
4216 # qemu-system-x86_64 \
4217   [...] \
4218       -object cryptodev-backend-builtin,id=cryptodev0 \
4219       -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4220   [...]
4221@end example
4222
4223@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4224@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4225
4226Defines a secret to store a password, encryption key, or some other sensitive
4227data. The sensitive data can either be passed directly via the @var{data}
4228parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4229parameter is insecure unless the sensitive data is encrypted.
4230
4231The sensitive data can be provided in raw format (the default), or base64.
4232When encoded as JSON, the raw format only supports valid UTF-8 characters,
4233so base64 is recommended for sending binary data. QEMU will convert from
4234which ever format is provided to the format it needs internally. eg, an
4235RBD password can be provided in raw format, even though it will be base64
4236encoded when passed onto the RBD sever.
4237
4238For added protection, it is possible to encrypt the data associated with
4239a secret using the AES-256-CBC cipher. Use of encryption is indicated
4240by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4241parameter provides the ID of a previously defined secret that contains
4242the AES-256 decryption key. This key should be 32-bytes long and be
4243base64 encoded. The @var{iv} parameter provides the random initialization
4244vector used for encryption of this particular secret and should be a
4245base64 encrypted string of the 16-byte IV.
4246
4247The simplest (insecure) usage is to provide the secret inline
4248
4249@example
4250
4251 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4252
4253@end example
4254
4255The simplest secure usage is to provide the secret via a file
4256
4257 # printf "letmein" > mypasswd.txt
4258 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4259
4260For greater security, AES-256-CBC should be used. To illustrate usage,
4261consider the openssl command line tool which can encrypt the data. Note
4262that when encrypting, the plaintext must be padded to the cipher block
4263size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4264
4265First a master key needs to be created in base64 encoding:
4266
4267@example
4268 # openssl rand -base64 32 > key.b64
4269 # KEY=$(base64 -d key.b64 | hexdump  -v -e '/1 "%02X"')
4270@end example
4271
4272Each secret to be encrypted needs to have a random initialization vector
4273generated. These do not need to be kept secret
4274
4275@example
4276 # openssl rand -base64 16 > iv.b64
4277 # IV=$(base64 -d iv.b64 | hexdump  -v -e '/1 "%02X"')
4278@end example
4279
4280The secret to be defined can now be encrypted, in this case we're
4281telling openssl to base64 encode the result, but it could be left
4282as raw bytes if desired.
4283
4284@example
4285 # SECRET=$(printf "letmein" |
4286            openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4287@end example
4288
4289When launching QEMU, create a master secret pointing to @code{key.b64}
4290and specify that to be used to decrypt the user password. Pass the
4291contents of @code{iv.b64} to the second secret
4292
4293@example
4294 # $QEMU \
4295     -object secret,id=secmaster0,format=base64,file=key.b64 \
4296     -object secret,id=sec0,keyid=secmaster0,format=base64,\
4297         data=$SECRET,iv=$(<iv.b64)
4298@end example
4299
4300@end table
4301
4302ETEXI
4303
4304
4305HXCOMM This is the last statement. Insert new options before this line!
4306STEXI
4307@end table
4308ETEXI
4309