xref: /openbmc/qemu/qemu-options.hx (revision 29b22c79)
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, whpx or tcg (default: tcg)\n"
35    "                kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n"
36    "                vmport=on|off|auto controls emulation of vmport (default: auto)\n"
37    "                kvm_shadow_mem=size of KVM shadow MMU in bytes\n"
38    "                dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
39    "                mem-merge=on|off controls memory merge support (default: on)\n"
40    "                igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
41    "                aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
42    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
43    "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
44    "                nvdimm=on|off controls NVDIMM support (default=off)\n"
45    "                enforce-config-section=on|off enforce configuration section migration (default=off)\n"
46    "                s390-squash-mcss=on|off (deprecated) controls support for squashing into default css (default=off)\n",
47    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, whpx 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, whpx 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, whpx 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 braille
1225Braille device.  This will use BrlAPI to display the braille output on a real
1226or fake device.
1227
1228@end table
1229ETEXI
1230
1231STEXI
1232@end table
1233ETEXI
1234DEFHEADING()
1235
1236DEFHEADING(Display options:)
1237STEXI
1238@table @option
1239ETEXI
1240
1241DEF("display", HAS_ARG, QEMU_OPTION_display,
1242    "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1243    "            [,window_close=on|off][,gl=on|off]\n"
1244    "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1245    "-display vnc=<display>[,<optargs>]\n"
1246    "-display curses\n"
1247    "-display none"
1248    "                select display type\n"
1249    "The default display is equivalent to\n"
1250#if defined(CONFIG_GTK)
1251            "\t\"-display gtk\"\n"
1252#elif defined(CONFIG_SDL)
1253            "\t\"-display sdl\"\n"
1254#elif defined(CONFIG_COCOA)
1255            "\t\"-display cocoa\"\n"
1256#elif defined(CONFIG_VNC)
1257            "\t\"-vnc localhost:0,to=99,id=default\"\n"
1258#else
1259            "\t\"-display none\"\n"
1260#endif
1261    , QEMU_ARCH_ALL)
1262STEXI
1263@item -display @var{type}
1264@findex -display
1265Select type of display to use. This option is a replacement for the
1266old style -sdl/-curses/... options. Valid values for @var{type} are
1267@table @option
1268@item sdl
1269Display video output via SDL (usually in a separate graphics
1270window; see the SDL documentation for other possibilities).
1271@item curses
1272Display video output via curses. For graphics device models which
1273support a text mode, QEMU can display this output using a
1274curses/ncurses interface. Nothing is displayed when the graphics
1275device is in graphical mode or if the graphics device does not support
1276a text mode. Generally only the VGA device models support text mode.
1277@item none
1278Do not display video output. The guest will still see an emulated
1279graphics card, but its output will not be displayed to the QEMU
1280user. This option differs from the -nographic option in that it
1281only affects what is done with video output; -nographic also changes
1282the destination of the serial and parallel port data.
1283@item gtk
1284Display video output in a GTK window. This interface provides drop-down
1285menus and other UI elements to configure and control the VM during
1286runtime.
1287@item vnc
1288Start a VNC server on display <arg>
1289@end table
1290ETEXI
1291
1292DEF("nographic", 0, QEMU_OPTION_nographic,
1293    "-nographic      disable graphical output and redirect serial I/Os to console\n",
1294    QEMU_ARCH_ALL)
1295STEXI
1296@item -nographic
1297@findex -nographic
1298Normally, if QEMU is compiled with graphical window support, it displays
1299output such as guest graphics, guest console, and the QEMU monitor in a
1300window. With this option, you can totally disable graphical output so
1301that QEMU is a simple command line application. The emulated serial port
1302is redirected on the console and muxed with the monitor (unless
1303redirected elsewhere explicitly). Therefore, you can still use QEMU to
1304debug a Linux kernel with a serial console. Use @key{C-a h} for help on
1305switching between the console and monitor.
1306ETEXI
1307
1308DEF("curses", 0, QEMU_OPTION_curses,
1309    "-curses         shorthand for -display curses\n",
1310    QEMU_ARCH_ALL)
1311STEXI
1312@item -curses
1313@findex -curses
1314Normally, if QEMU is compiled with graphical window support, it displays
1315output such as guest graphics, guest console, and the QEMU monitor in a
1316window. With this option, QEMU can display the VGA output when in text
1317mode using a curses/ncurses interface. Nothing is displayed in graphical
1318mode.
1319ETEXI
1320
1321DEF("no-frame", 0, QEMU_OPTION_no_frame,
1322    "-no-frame       open SDL window without a frame and window decorations\n",
1323    QEMU_ARCH_ALL)
1324STEXI
1325@item -no-frame
1326@findex -no-frame
1327Do not use decorations for SDL windows and start them using the whole
1328available screen space. This makes the using QEMU in a dedicated desktop
1329workspace more convenient.
1330ETEXI
1331
1332DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1333    "-alt-grab       use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1334    QEMU_ARCH_ALL)
1335STEXI
1336@item -alt-grab
1337@findex -alt-grab
1338Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1339affects the special keys (for fullscreen, monitor-mode switching, etc).
1340ETEXI
1341
1342DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1343    "-ctrl-grab      use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1344    QEMU_ARCH_ALL)
1345STEXI
1346@item -ctrl-grab
1347@findex -ctrl-grab
1348Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1349affects the special keys (for fullscreen, monitor-mode switching, etc).
1350ETEXI
1351
1352DEF("no-quit", 0, QEMU_OPTION_no_quit,
1353    "-no-quit        disable SDL window close capability\n", QEMU_ARCH_ALL)
1354STEXI
1355@item -no-quit
1356@findex -no-quit
1357Disable SDL window close capability.
1358ETEXI
1359
1360DEF("sdl", 0, QEMU_OPTION_sdl,
1361    "-sdl            shorthand for -display sdl\n", QEMU_ARCH_ALL)
1362STEXI
1363@item -sdl
1364@findex -sdl
1365Enable SDL.
1366ETEXI
1367
1368DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1369    "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1370    "       [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1371    "       [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1372    "       [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1373    "       [,tls-ciphers=<list>]\n"
1374    "       [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1375    "       [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1376    "       [,sasl][,password=<secret>][,disable-ticketing]\n"
1377    "       [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1378    "       [,jpeg-wan-compression=[auto|never|always]]\n"
1379    "       [,zlib-glz-wan-compression=[auto|never|always]]\n"
1380    "       [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1381    "       [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1382    "       [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1383    "       [,gl=[on|off]][,rendernode=<file>]\n"
1384    "   enable spice\n"
1385    "   at least one of {port, tls-port} is mandatory\n",
1386    QEMU_ARCH_ALL)
1387STEXI
1388@item -spice @var{option}[,@var{option}[,...]]
1389@findex -spice
1390Enable the spice remote desktop protocol. Valid options are
1391
1392@table @option
1393
1394@item port=<nr>
1395Set the TCP port spice is listening on for plaintext channels.
1396
1397@item addr=<addr>
1398Set the IP address spice is listening on.  Default is any address.
1399
1400@item ipv4
1401@itemx ipv6
1402@itemx unix
1403Force using the specified IP version.
1404
1405@item password=<secret>
1406Set the password you need to authenticate.
1407
1408@item sasl
1409Require that the client use SASL to authenticate with the spice.
1410The exact choice of authentication method used is controlled from the
1411system / user's SASL configuration file for the 'qemu' service. This
1412is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1413unprivileged user, an environment variable SASL_CONF_PATH can be used
1414to make it search alternate locations for the service config.
1415While some SASL auth methods can also provide data encryption (eg GSSAPI),
1416it is recommended that SASL always be combined with the 'tls' and
1417'x509' settings to enable use of SSL and server certificates. This
1418ensures a data encryption preventing compromise of authentication
1419credentials.
1420
1421@item disable-ticketing
1422Allow client connects without authentication.
1423
1424@item disable-copy-paste
1425Disable copy paste between the client and the guest.
1426
1427@item disable-agent-file-xfer
1428Disable spice-vdagent based file-xfer between the client and the guest.
1429
1430@item tls-port=<nr>
1431Set the TCP port spice is listening on for encrypted channels.
1432
1433@item x509-dir=<dir>
1434Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1435
1436@item x509-key-file=<file>
1437@itemx x509-key-password=<file>
1438@itemx x509-cert-file=<file>
1439@itemx x509-cacert-file=<file>
1440@itemx x509-dh-key-file=<file>
1441The x509 file names can also be configured individually.
1442
1443@item tls-ciphers=<list>
1444Specify which ciphers to use.
1445
1446@item tls-channel=[main|display|cursor|inputs|record|playback]
1447@itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1448Force specific channel to be used with or without TLS encryption.  The
1449options can be specified multiple times to configure multiple
1450channels.  The special name "default" can be used to set the default
1451mode.  For channels which are not explicitly forced into one mode the
1452spice client is allowed to pick tls/plaintext as he pleases.
1453
1454@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1455Configure image compression (lossless).
1456Default is auto_glz.
1457
1458@item jpeg-wan-compression=[auto|never|always]
1459@itemx zlib-glz-wan-compression=[auto|never|always]
1460Configure wan image compression (lossy for slow links).
1461Default is auto.
1462
1463@item streaming-video=[off|all|filter]
1464Configure video stream detection.  Default is off.
1465
1466@item agent-mouse=[on|off]
1467Enable/disable passing mouse events via vdagent.  Default is on.
1468
1469@item playback-compression=[on|off]
1470Enable/disable audio stream compression (using celt 0.5.1).  Default is on.
1471
1472@item seamless-migration=[on|off]
1473Enable/disable spice seamless migration. Default is off.
1474
1475@item gl=[on|off]
1476Enable/disable OpenGL context. Default is off.
1477
1478@item rendernode=<file>
1479DRM render node for OpenGL rendering. If not specified, it will pick
1480the first available. (Since 2.9)
1481
1482@end table
1483ETEXI
1484
1485DEF("portrait", 0, QEMU_OPTION_portrait,
1486    "-portrait       rotate graphical output 90 deg left (only PXA LCD)\n",
1487    QEMU_ARCH_ALL)
1488STEXI
1489@item -portrait
1490@findex -portrait
1491Rotate graphical output 90 deg left (only PXA LCD).
1492ETEXI
1493
1494DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1495    "-rotate <deg>   rotate graphical output some deg left (only PXA LCD)\n",
1496    QEMU_ARCH_ALL)
1497STEXI
1498@item -rotate @var{deg}
1499@findex -rotate
1500Rotate graphical output some deg left (only PXA LCD).
1501ETEXI
1502
1503DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1504    "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1505    "                select video card type\n", QEMU_ARCH_ALL)
1506STEXI
1507@item -vga @var{type}
1508@findex -vga
1509Select type of VGA card to emulate. Valid values for @var{type} are
1510@table @option
1511@item cirrus
1512Cirrus Logic GD5446 Video card. All Windows versions starting from
1513Windows 95 should recognize and use this graphic card. For optimal
1514performances, use 16 bit color depth in the guest and the host OS.
1515(This card was the default before QEMU 2.2)
1516@item std
1517Standard VGA card with Bochs VBE extensions.  If your guest OS
1518supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1519to use high resolution modes (>= 1280x1024x16) then you should use
1520this option. (This card is the default since QEMU 2.2)
1521@item vmware
1522VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1523recent XFree86/XOrg server or Windows guest with a driver for this
1524card.
1525@item qxl
1526QXL paravirtual graphic card.  It is VGA compatible (including VESA
15272.0 VBE support).  Works best with qxl guest drivers installed though.
1528Recommended choice when using the spice protocol.
1529@item tcx
1530(sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1531sun4m machines and offers both 8-bit and 24-bit colour depths at a
1532fixed resolution of 1024x768.
1533@item cg3
1534(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1535for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1536resolutions aimed at people wishing to run older Solaris versions.
1537@item virtio
1538Virtio VGA card.
1539@item none
1540Disable VGA card.
1541@end table
1542ETEXI
1543
1544DEF("full-screen", 0, QEMU_OPTION_full_screen,
1545    "-full-screen    start in full screen\n", QEMU_ARCH_ALL)
1546STEXI
1547@item -full-screen
1548@findex -full-screen
1549Start in full screen.
1550ETEXI
1551
1552DEF("g", 1, QEMU_OPTION_g ,
1553    "-g WxH[xDEPTH]  Set the initial graphical resolution and depth\n",
1554    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1555STEXI
1556@item -g @var{width}x@var{height}[x@var{depth}]
1557@findex -g
1558Set the initial graphical resolution and depth (PPC, SPARC only).
1559ETEXI
1560
1561DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1562    "-vnc <display>  shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1563STEXI
1564@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1565@findex -vnc
1566Normally, if QEMU is compiled with graphical window support, it displays
1567output such as guest graphics, guest console, and the QEMU monitor in a
1568window. With this option, you can have QEMU listen on VNC display
1569@var{display} and redirect the VGA display over the VNC session. It is
1570very useful to enable the usb tablet device when using this option
1571(option @option{-device usb-tablet}). When using the VNC display, you
1572must use the @option{-k} parameter to set the keyboard layout if you are
1573not using en-us. Valid syntax for the @var{display} is
1574
1575@table @option
1576
1577@item to=@var{L}
1578
1579With this option, QEMU will try next available VNC @var{display}s, until the
1580number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1581available, e.g. port 5900+@var{display} is already used by another
1582application. By default, to=0.
1583
1584@item @var{host}:@var{d}
1585
1586TCP connections will only be allowed from @var{host} on display @var{d}.
1587By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1588be omitted in which case the server will accept connections from any host.
1589
1590@item unix:@var{path}
1591
1592Connections will be allowed over UNIX domain sockets where @var{path} is the
1593location of a unix socket to listen for connections on.
1594
1595@item none
1596
1597VNC is initialized but not started. The monitor @code{change} command
1598can be used to later start the VNC server.
1599
1600@end table
1601
1602Following the @var{display} value there may be one or more @var{option} flags
1603separated by commas. Valid options are
1604
1605@table @option
1606
1607@item reverse
1608
1609Connect to a listening VNC client via a ``reverse'' connection. The
1610client is specified by the @var{display}. For reverse network
1611connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1612is a TCP port number, not a display number.
1613
1614@item websocket
1615
1616Opens an additional TCP listening port dedicated to VNC Websocket connections.
1617If a bare @var{websocket} option is given, the Websocket port is
16185700+@var{display}. An alternative port can be specified with the
1619syntax @code{websocket}=@var{port}.
1620
1621If @var{host} is specified connections will only be allowed from this host.
1622It is possible to control the websocket listen address independently, using
1623the syntax @code{websocket}=@var{host}:@var{port}.
1624
1625If no TLS credentials are provided, the websocket connection runs in
1626unencrypted mode. If TLS credentials are provided, the websocket connection
1627requires encrypted client connections.
1628
1629@item password
1630
1631Require that password based authentication is used for client connections.
1632
1633The password must be set separately using the @code{set_password} command in
1634the @ref{pcsys_monitor}. The syntax to change your password is:
1635@code{set_password <protocol> <password>} where <protocol> could be either
1636"vnc" or "spice".
1637
1638If you would like to change <protocol> password expiration, you should use
1639@code{expire_password <protocol> <expiration-time>} where expiration time could
1640be one of the following options: now, never, +seconds or UNIX time of
1641expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1642to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1643date and time).
1644
1645You can also use keywords "now" or "never" for the expiration time to
1646allow <protocol> password to expire immediately or never expire.
1647
1648@item tls-creds=@var{ID}
1649
1650Provides the ID of a set of TLS credentials to use to secure the
1651VNC server. They will apply to both the normal VNC server socket
1652and the websocket socket (if enabled). Setting TLS credentials
1653will cause the VNC server socket to enable the VeNCrypt auth
1654mechanism.  The credentials should have been previously created
1655using the @option{-object tls-creds} argument.
1656
1657The @option{tls-creds} parameter obsoletes the @option{tls},
1658@option{x509}, and @option{x509verify} options, and as such
1659it is not permitted to set both new and old type options at
1660the same time.
1661
1662@item tls
1663
1664Require that client use TLS when communicating with the VNC server. This
1665uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1666attack. It is recommended that this option be combined with either the
1667@option{x509} or @option{x509verify} options.
1668
1669This option is now deprecated in favor of using the @option{tls-creds}
1670argument.
1671
1672@item x509=@var{/path/to/certificate/dir}
1673
1674Valid if @option{tls} is specified. Require that x509 credentials are used
1675for negotiating the TLS session. The server will send its x509 certificate
1676to the client. It is recommended that a password be set on the VNC server
1677to provide authentication of the client when this is used. The path following
1678this option specifies where the x509 certificates are to be loaded from.
1679See the @ref{vnc_security} section for details on generating certificates.
1680
1681This option is now deprecated in favour of using the @option{tls-creds}
1682argument.
1683
1684@item x509verify=@var{/path/to/certificate/dir}
1685
1686Valid if @option{tls} is specified. Require that x509 credentials are used
1687for negotiating the TLS session. The server will send its x509 certificate
1688to the client, and request that the client send its own x509 certificate.
1689The server will validate the client's certificate against the CA certificate,
1690and reject clients when validation fails. If the certificate authority is
1691trusted, this is a sufficient authentication mechanism. You may still wish
1692to set a password on the VNC server as a second authentication layer. The
1693path following this option specifies where the x509 certificates are to
1694be loaded from. See the @ref{vnc_security} section for details on generating
1695certificates.
1696
1697This option is now deprecated in favour of using the @option{tls-creds}
1698argument.
1699
1700@item sasl
1701
1702Require that the client use SASL to authenticate with the VNC server.
1703The exact choice of authentication method used is controlled from the
1704system / user's SASL configuration file for the 'qemu' service. This
1705is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1706unprivileged user, an environment variable SASL_CONF_PATH can be used
1707to make it search alternate locations for the service config.
1708While some SASL auth methods can also provide data encryption (eg GSSAPI),
1709it is recommended that SASL always be combined with the 'tls' and
1710'x509' settings to enable use of SSL and server certificates. This
1711ensures a data encryption preventing compromise of authentication
1712credentials. See the @ref{vnc_security} section for details on using
1713SASL authentication.
1714
1715@item acl
1716
1717Turn on access control lists for checking of the x509 client certificate
1718and SASL party. For x509 certs, the ACL check is made against the
1719certificate's distinguished name. This is something that looks like
1720@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1721made against the username, which depending on the SASL plugin, may
1722include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1723When the @option{acl} flag is set, the initial access list will be
1724empty, with a @code{deny} policy. Thus no one will be allowed to
1725use the VNC server until the ACLs have been loaded. This can be
1726achieved using the @code{acl} monitor command.
1727
1728@item lossy
1729
1730Enable lossy compression methods (gradient, JPEG, ...). If this
1731option is set, VNC client may receive lossy framebuffer updates
1732depending on its encoding settings. Enabling this option can save
1733a lot of bandwidth at the expense of quality.
1734
1735@item non-adaptive
1736
1737Disable adaptive encodings. Adaptive encodings are enabled by default.
1738An adaptive encoding will try to detect frequently updated screen regions,
1739and send updates in these regions using a lossy encoding (like JPEG).
1740This can be really helpful to save bandwidth when playing videos. Disabling
1741adaptive encodings restores the original static behavior of encodings
1742like Tight.
1743
1744@item share=[allow-exclusive|force-shared|ignore]
1745
1746Set display sharing policy.  'allow-exclusive' allows clients to ask
1747for exclusive access.  As suggested by the rfb spec this is
1748implemented by dropping other connections.  Connecting multiple
1749clients in parallel requires all clients asking for a shared session
1750(vncviewer: -shared switch).  This is the default.  'force-shared'
1751disables exclusive client access.  Useful for shared desktop sessions,
1752where you don't want someone forgetting specify -shared disconnect
1753everybody else.  'ignore' completely ignores the shared flag and
1754allows everybody connect unconditionally.  Doesn't conform to the rfb
1755spec but is traditional QEMU behavior.
1756
1757@item key-delay-ms
1758
1759Set keyboard delay, for key down and key up events, in milliseconds.
1760Default is 10.  Keyboards are low-bandwidth devices, so this slowdown
1761can help the device and guest to keep up and not lose events in case
1762events are arriving in bulk.  Possible causes for the latter are flaky
1763network connections, or scripts for automated testing.
1764
1765@end table
1766ETEXI
1767
1768STEXI
1769@end table
1770ETEXI
1771ARCHHEADING(, QEMU_ARCH_I386)
1772
1773ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1774STEXI
1775@table @option
1776ETEXI
1777
1778DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1779    "-win2k-hack     use it when installing Windows 2000 to avoid a disk full bug\n",
1780    QEMU_ARCH_I386)
1781STEXI
1782@item -win2k-hack
1783@findex -win2k-hack
1784Use it when installing Windows 2000 to avoid a disk full bug. After
1785Windows 2000 is installed, you no longer need this option (this option
1786slows down the IDE transfers).
1787ETEXI
1788
1789HXCOMM Deprecated by -rtc
1790DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1791
1792DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1793    "-no-fd-bootchk  disable boot signature checking for floppy disks\n",
1794    QEMU_ARCH_I386)
1795STEXI
1796@item -no-fd-bootchk
1797@findex -no-fd-bootchk
1798Disable boot signature checking for floppy disks in BIOS. May
1799be needed to boot from old floppy disks.
1800ETEXI
1801
1802DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1803           "-no-acpi        disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1804STEXI
1805@item -no-acpi
1806@findex -no-acpi
1807Disable ACPI (Advanced Configuration and Power Interface) support. Use
1808it if your guest OS complains about ACPI problems (PC target machine
1809only).
1810ETEXI
1811
1812DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1813    "-no-hpet        disable HPET\n", QEMU_ARCH_I386)
1814STEXI
1815@item -no-hpet
1816@findex -no-hpet
1817Disable HPET support.
1818ETEXI
1819
1820DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1821    "-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,{data|file}=file1[:file2]...]\n"
1822    "                ACPI table description\n", QEMU_ARCH_I386)
1823STEXI
1824@item -acpitable [sig=@var{str}][,rev=@var{n}][,oem_id=@var{str}][,oem_table_id=@var{str}][,oem_rev=@var{n}] [,asl_compiler_id=@var{str}][,asl_compiler_rev=@var{n}][,data=@var{file1}[:@var{file2}]...]
1825@findex -acpitable
1826Add ACPI table with specified header fields and context from specified files.
1827For file=, take whole ACPI table from the specified files, including all
1828ACPI headers (possible overridden by other options).
1829For data=, only data
1830portion of the table is used, all header information is specified in the
1831command line.
1832If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1833fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1834to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1835spec.
1836ETEXI
1837
1838DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1839    "-smbios file=binary\n"
1840    "                load SMBIOS entry from binary file\n"
1841    "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1842    "              [,uefi=on|off]\n"
1843    "                specify SMBIOS type 0 fields\n"
1844    "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1845    "              [,uuid=uuid][,sku=str][,family=str]\n"
1846    "                specify SMBIOS type 1 fields\n"
1847    "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1848    "              [,asset=str][,location=str]\n"
1849    "                specify SMBIOS type 2 fields\n"
1850    "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1851    "              [,sku=str]\n"
1852    "                specify SMBIOS type 3 fields\n"
1853    "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1854    "              [,asset=str][,part=str]\n"
1855    "                specify SMBIOS type 4 fields\n"
1856    "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1857    "               [,asset=str][,part=str][,speed=%d]\n"
1858    "                specify SMBIOS type 17 fields\n",
1859    QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1860STEXI
1861@item -smbios file=@var{binary}
1862@findex -smbios
1863Load SMBIOS entry from binary file.
1864
1865@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1866Specify SMBIOS type 0 fields
1867
1868@item -smbios type=1[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,uuid=@var{uuid}][,sku=@var{str}][,family=@var{str}]
1869Specify SMBIOS type 1 fields
1870
1871@item -smbios type=2[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,location=@var{str}][,family=@var{str}]
1872Specify SMBIOS type 2 fields
1873
1874@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1875Specify SMBIOS type 3 fields
1876
1877@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1878Specify SMBIOS type 4 fields
1879
1880@item -smbios type=17[,loc_pfx=@var{str}][,bank=@var{str}][,manufacturer=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}][,speed=@var{%d}]
1881Specify SMBIOS type 17 fields
1882ETEXI
1883
1884STEXI
1885@end table
1886ETEXI
1887DEFHEADING()
1888
1889DEFHEADING(Network options:)
1890STEXI
1891@table @option
1892ETEXI
1893
1894HXCOMM Legacy slirp options (now moved to -net user):
1895#ifdef CONFIG_SLIRP
1896DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1897DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1898DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1899#ifndef _WIN32
1900DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1901#endif
1902#endif
1903
1904DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1905#ifdef CONFIG_SLIRP
1906    "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1907    "         [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1908    "         [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1909    "         [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1910    "         [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1911#ifndef _WIN32
1912                                             "[,smb=dir[,smbserver=addr]]\n"
1913#endif
1914    "                configure a user mode network backend with ID 'str',\n"
1915    "                its DHCP server and optional services\n"
1916#endif
1917#ifdef _WIN32
1918    "-netdev tap,id=str,ifname=name\n"
1919    "                configure a host TAP network backend with ID 'str'\n"
1920#else
1921    "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1922    "         [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1923    "         [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1924    "         [,poll-us=n]\n"
1925    "                configure a host TAP network backend with ID 'str'\n"
1926    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1927    "                use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1928    "                to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1929    "                to deconfigure it\n"
1930    "                use '[down]script=no' to disable script execution\n"
1931    "                use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1932    "                configure it\n"
1933    "                use 'fd=h' to connect to an already opened TAP interface\n"
1934    "                use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1935    "                use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1936    "                default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1937    "                use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1938    "                use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1939    "                use vhost=on to enable experimental in kernel accelerator\n"
1940    "                    (only has effect for virtio guests which use MSIX)\n"
1941    "                use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1942    "                use 'vhostfd=h' to connect to an already opened vhost net device\n"
1943    "                use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1944    "                use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1945    "                use 'poll-us=n' to speciy the maximum number of microseconds that could be\n"
1946    "                spent on busy polling for vhost net\n"
1947    "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1948    "                configure a host TAP network backend with ID 'str' that is\n"
1949    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1950    "                using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1951#endif
1952#ifdef __linux__
1953    "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1954    "         [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1955    "         [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1956    "         [,rxcookie=rxcookie][,offset=offset]\n"
1957    "                configure a network backend with ID 'str' connected to\n"
1958    "                an Ethernet over L2TPv3 pseudowire.\n"
1959    "                Linux kernel 3.3+ as well as most routers can talk\n"
1960    "                L2TPv3. This transport allows connecting a VM to a VM,\n"
1961    "                VM to a router and even VM to Host. It is a nearly-universal\n"
1962    "                standard (RFC3391). Note - this implementation uses static\n"
1963    "                pre-configured tunnels (same as the Linux kernel).\n"
1964    "                use 'src=' to specify source address\n"
1965    "                use 'dst=' to specify destination address\n"
1966    "                use 'udp=on' to specify udp encapsulation\n"
1967    "                use 'srcport=' to specify source udp port\n"
1968    "                use 'dstport=' to specify destination udp port\n"
1969    "                use 'ipv6=on' to force v6\n"
1970    "                L2TPv3 uses cookies to prevent misconfiguration as\n"
1971    "                well as a weak security measure\n"
1972    "                use 'rxcookie=0x012345678' to specify a rxcookie\n"
1973    "                use 'txcookie=0x012345678' to specify a txcookie\n"
1974    "                use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1975    "                use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1976    "                use 'pincounter=on' to work around broken counter handling in peer\n"
1977    "                use 'offset=X' to add an extra offset between header and data\n"
1978#endif
1979    "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1980    "                configure a network backend to connect to another network\n"
1981    "                using a socket connection\n"
1982    "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1983    "                configure a network backend to connect to a multicast maddr and port\n"
1984    "                use 'localaddr=addr' to specify the host address to send packets from\n"
1985    "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1986    "                configure a network backend to connect to another network\n"
1987    "                using an UDP tunnel\n"
1988#ifdef CONFIG_VDE
1989    "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1990    "                configure a network backend to connect to port 'n' of a vde switch\n"
1991    "                running on host and listening for incoming connections on 'socketpath'.\n"
1992    "                Use group 'groupname' and mode 'octalmode' to change default\n"
1993    "                ownership and permissions for communication port.\n"
1994#endif
1995#ifdef CONFIG_NETMAP
1996    "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1997    "                attach to the existing netmap-enabled network interface 'name', or to a\n"
1998    "                VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1999    "                netmap device, defaults to '/dev/netmap')\n"
2000#endif
2001    "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
2002    "                configure a vhost-user network, backed by a chardev 'dev'\n"
2003    "-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
2004    "                configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL)
2005DEF("net", HAS_ARG, QEMU_OPTION_net,
2006    "-net nic[,vlan=n][,netdev=nd][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2007    "                configure or create an on-board (or machine default) NIC and\n"
2008    "                connect it either to VLAN 'n' or the netdev 'nd' (for pluggable\n"
2009    "                NICs please use '-device devtype,netdev=nd' instead)\n"
2010    "-net dump[,vlan=n][,file=f][,len=n]\n"
2011    "                dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
2012    "-net none       use it alone to have zero network devices. If no -net option\n"
2013    "                is provided, the default is '-net nic -net user'\n"
2014    "-net ["
2015#ifdef CONFIG_SLIRP
2016    "user|"
2017#endif
2018    "tap|"
2019    "bridge|"
2020#ifdef CONFIG_VDE
2021    "vde|"
2022#endif
2023#ifdef CONFIG_NETMAP
2024    "netmap|"
2025#endif
2026    "socket][,vlan=n][,option][,option][,...]\n"
2027    "                old way to initialize a host network interface\n"
2028    "                (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2029STEXI
2030@item -net nic[,vlan=@var{n}][,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2031@findex -net
2032Configure or create an on-board (or machine default) Network Interface Card
2033(NIC) and connect it either to VLAN @var{n} (@var{n} = 0 is the default), or
2034to the netdev @var{nd}. The NIC is an e1000 by default on the PC
2035target. Optionally, the MAC address can be changed to @var{mac}, the
2036device address set to @var{addr} (PCI cards only),
2037and a @var{name} can be assigned for use in monitor commands.
2038Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2039that the card should have; this option currently only affects virtio cards; set
2040@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2041NIC is created.  QEMU can emulate several different models of network card.
2042Valid values for @var{type} are
2043@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
2044@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
2045@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
2046Not all devices are supported on all targets.  Use @code{-net nic,model=help}
2047for a list of available devices for your target.
2048
2049@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2050@findex -netdev
2051@item -net user[,@var{option}][,@var{option}][,...]
2052Use the user mode network stack which requires no administrator
2053privilege to run. Valid options are:
2054
2055@table @option
2056@item vlan=@var{n}
2057Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
2058
2059@item id=@var{id}
2060@itemx name=@var{name}
2061Assign symbolic name for use in monitor commands.
2062
2063@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
2064be enabled.  If neither is specified both protocols are enabled.
2065
2066@item net=@var{addr}[/@var{mask}]
2067Set IP network address the guest will see. Optionally specify the netmask,
2068either in the form a.b.c.d or as number of valid top-most bits. Default is
206910.0.2.0/24.
2070
2071@item host=@var{addr}
2072Specify the guest-visible address of the host. Default is the 2nd IP in the
2073guest network, i.e. x.x.x.2.
2074
2075@item ipv6-net=@var{addr}[/@var{int}]
2076Set IPv6 network address the guest will see (default is fec0::/64). The
2077network prefix is given in the usual hexadecimal IPv6 address
2078notation. The prefix size is optional, and is given as the number of
2079valid top-most bits (default is 64).
2080
2081@item ipv6-host=@var{addr}
2082Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2083the guest network, i.e. xxxx::2.
2084
2085@item restrict=on|off
2086If this option is enabled, the guest will be isolated, i.e. it will not be
2087able to contact the host and no guest IP packets will be routed over the host
2088to the outside. This option does not affect any explicitly set forwarding rules.
2089
2090@item hostname=@var{name}
2091Specifies the client hostname reported by the built-in DHCP server.
2092
2093@item dhcpstart=@var{addr}
2094Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2095is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2096
2097@item dns=@var{addr}
2098Specify the guest-visible address of the virtual nameserver. The address must
2099be different from the host address. Default is the 3rd IP in the guest network,
2100i.e. x.x.x.3.
2101
2102@item ipv6-dns=@var{addr}
2103Specify the guest-visible address of the IPv6 virtual nameserver. The address
2104must be different from the host address. Default is the 3rd IP in the guest
2105network, i.e. xxxx::3.
2106
2107@item dnssearch=@var{domain}
2108Provides an entry for the domain-search list sent by the built-in
2109DHCP server. More than one domain suffix can be transmitted by specifying
2110this option multiple times. If supported, this will cause the guest to
2111automatically try to append the given domain suffix(es) in case a domain name
2112can not be resolved.
2113
2114Example:
2115@example
2116qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
2117@end example
2118
2119@item tftp=@var{dir}
2120When using the user mode network stack, activate a built-in TFTP
2121server. The files in @var{dir} will be exposed as the root of a TFTP server.
2122The TFTP client on the guest must be configured in binary mode (use the command
2123@code{bin} of the Unix TFTP client).
2124
2125@item bootfile=@var{file}
2126When using the user mode network stack, broadcast @var{file} as the BOOTP
2127filename. In conjunction with @option{tftp}, this can be used to network boot
2128a guest from a local directory.
2129
2130Example (using pxelinux):
2131@example
2132qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2133@end example
2134
2135@item smb=@var{dir}[,smbserver=@var{addr}]
2136When using the user mode network stack, activate a built-in SMB
2137server so that Windows OSes can access to the host files in @file{@var{dir}}
2138transparently. The IP address of the SMB server can be set to @var{addr}. By
2139default the 4th IP in the guest network is used, i.e. x.x.x.4.
2140
2141In the guest Windows OS, the line:
2142@example
214310.0.2.4 smbserver
2144@end example
2145must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2146or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2147
2148Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2149
2150Note that a SAMBA server must be installed on the host OS.
2151QEMU was tested successfully with smbd versions from Red Hat 9,
2152Fedora Core 3 and OpenSUSE 11.x.
2153
2154@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2155Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2156the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2157@var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2158given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2159be bound to a specific host interface. If no connection type is set, TCP is
2160used. This option can be given multiple times.
2161
2162For example, to redirect host X11 connection from screen 1 to guest
2163screen 0, use the following:
2164
2165@example
2166# on the host
2167qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
2168# this host xterm should open in the guest X11 server
2169xterm -display :1
2170@end example
2171
2172To redirect telnet connections from host port 5555 to telnet port on
2173the guest, use the following:
2174
2175@example
2176# on the host
2177qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
2178telnet localhost 5555
2179@end example
2180
2181Then when you use on the host @code{telnet localhost 5555}, you
2182connect to the guest telnet server.
2183
2184@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2185@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2186Forward guest TCP connections to the IP address @var{server} on port @var{port}
2187to the character device @var{dev} or to a program executed by @var{cmd:command}
2188which gets spawned for each connection. This option can be given multiple times.
2189
2190You can either use a chardev directly and have that one used throughout QEMU's
2191lifetime, like in the following example:
2192
2193@example
2194# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
2195# the guest accesses it
2196qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
2197@end example
2198
2199Or you can execute a command on every TCP connection established by the guest,
2200so that QEMU behaves similar to an inetd process for that virtual server:
2201
2202@example
2203# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
2204# and connect the TCP stream to its stdin/stdout
2205qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2206@end example
2207
2208@end table
2209
2210Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
2211processed and applied to -net user. Mixing them with the new configuration
2212syntax gives undefined results. Their use for new applications is discouraged
2213as they will be removed from future versions.
2214
2215@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2216@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}]
2217Connect the host TAP network interface @var{name} to VLAN @var{n}.
2218
2219Use the network script @var{file} to configure it and the network script
2220@var{dfile} to deconfigure it. If @var{name} is not provided, the OS
2221automatically provides one. The default network configure script is
2222@file{/etc/qemu-ifup} and the default network deconfigure script is
2223@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
2224to disable script execution.
2225
2226If running QEMU as an unprivileged user, use the network helper
2227@var{helper} to configure the TAP interface and attach it to the bridge.
2228The default network helper executable is @file{/path/to/qemu-bridge-helper}
2229and the default bridge device is @file{br0}.
2230
2231@option{fd}=@var{h} can be used to specify the handle of an already
2232opened host TAP interface.
2233
2234Examples:
2235
2236@example
2237#launch a QEMU instance with the default network script
2238qemu-system-i386 linux.img -net nic -net tap
2239@end example
2240
2241@example
2242#launch a QEMU instance with two NICs, each one connected
2243#to a TAP device
2244qemu-system-i386 linux.img \
2245        -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \
2246        -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1
2247@end example
2248
2249@example
2250#launch a QEMU instance with the default network helper to
2251#connect a TAP device to bridge br0
2252qemu-system-i386 linux.img \
2253                 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
2254@end example
2255
2256@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
2257@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
2258Connect a host TAP network interface to a host bridge device.
2259
2260Use the network helper @var{helper} to configure the TAP interface and
2261attach it to the bridge. The default network helper executable is
2262@file{/path/to/qemu-bridge-helper} and the default bridge
2263device is @file{br0}.
2264
2265Examples:
2266
2267@example
2268#launch a QEMU instance with the default network helper to
2269#connect a TAP device to bridge br0
2270qemu-system-i386 linux.img -net bridge -net nic,model=virtio
2271@end example
2272
2273@example
2274#launch a QEMU instance with the default network helper to
2275#connect a TAP device to bridge qemubr0
2276qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
2277@end example
2278
2279@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2280@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2281
2282Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
2283machine using a TCP socket connection. If @option{listen} is
2284specified, QEMU waits for incoming connections on @var{port}
2285(@var{host} is optional). @option{connect} is used to connect to
2286another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
2287specifies an already opened TCP socket.
2288
2289Example:
2290@example
2291# launch a first QEMU instance
2292qemu-system-i386 linux.img \
2293                 -net nic,macaddr=52:54:00:12:34:56 \
2294                 -net socket,listen=:1234
2295# connect the VLAN 0 of this instance to the VLAN 0
2296# of the first instance
2297qemu-system-i386 linux.img \
2298                 -net nic,macaddr=52:54:00:12:34:57 \
2299                 -net socket,connect=127.0.0.1:1234
2300@end example
2301
2302@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2303@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2304
2305Create a VLAN @var{n} shared with another QEMU virtual
2306machines using a UDP multicast socket, effectively making a bus for
2307every QEMU with same multicast address @var{maddr} and @var{port}.
2308NOTES:
2309@enumerate
2310@item
2311Several QEMU can be running on different hosts and share same bus (assuming
2312correct multicast setup for these hosts).
2313@item
2314mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
2315@url{http://user-mode-linux.sf.net}.
2316@item
2317Use @option{fd=h} to specify an already opened UDP multicast socket.
2318@end enumerate
2319
2320Example:
2321@example
2322# launch one QEMU instance
2323qemu-system-i386 linux.img \
2324                 -net nic,macaddr=52:54:00:12:34:56 \
2325                 -net socket,mcast=230.0.0.1:1234
2326# launch another QEMU instance on same "bus"
2327qemu-system-i386 linux.img \
2328                 -net nic,macaddr=52:54:00:12:34:57 \
2329                 -net socket,mcast=230.0.0.1:1234
2330# launch yet another QEMU instance on same "bus"
2331qemu-system-i386 linux.img \
2332                 -net nic,macaddr=52:54:00:12:34:58 \
2333                 -net socket,mcast=230.0.0.1:1234
2334@end example
2335
2336Example (User Mode Linux compat.):
2337@example
2338# launch QEMU instance (note mcast address selected
2339# is UML's default)
2340qemu-system-i386 linux.img \
2341                 -net nic,macaddr=52:54:00:12:34:56 \
2342                 -net socket,mcast=239.192.168.1:1102
2343# launch UML
2344/path/to/linux ubd0=/path/to/root_fs eth0=mcast
2345@end example
2346
2347Example (send packets from host's 1.2.3.4):
2348@example
2349qemu-system-i386 linux.img \
2350                 -net nic,macaddr=52:54:00:12:34:56 \
2351                 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2352@end example
2353
2354@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}]
2355@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}]
2356Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
2357protocol to transport Ethernet (and other Layer 2) data frames between
2358two systems. It is present in routers, firewalls and the Linux kernel
2359(from version 3.3 onwards).
2360
2361This transport allows a VM to communicate to another VM, router or firewall directly.
2362
2363@table @option
2364@item src=@var{srcaddr}
2365    source address (mandatory)
2366@item dst=@var{dstaddr}
2367    destination address (mandatory)
2368@item udp
2369    select udp encapsulation (default is ip).
2370@item srcport=@var{srcport}
2371    source udp port.
2372@item dstport=@var{dstport}
2373    destination udp port.
2374@item ipv6
2375    force v6, otherwise defaults to v4.
2376@item rxcookie=@var{rxcookie}
2377@itemx txcookie=@var{txcookie}
2378    Cookies are a weak form of security in the l2tpv3 specification.
2379Their function is mostly to prevent misconfiguration. By default they are 32
2380bit.
2381@item cookie64
2382    Set cookie size to 64 bit instead of the default 32
2383@item counter=off
2384    Force a 'cut-down' L2TPv3 with no counter as in
2385draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2386@item pincounter=on
2387    Work around broken counter handling in peer. This may also help on
2388networks which have packet reorder.
2389@item offset=@var{offset}
2390    Add an extra offset between header and data
2391@end table
2392
2393For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2394on the remote Linux host 1.2.3.4:
2395@example
2396# Setup tunnel on linux host using raw ip as encapsulation
2397# on 1.2.3.4
2398ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2399    encap udp udp_sport 16384 udp_dport 16384
2400ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2401    0xFFFFFFFF peer_session_id 0xFFFFFFFF
2402ifconfig vmtunnel0 mtu 1500
2403ifconfig vmtunnel0 up
2404brctl addif br-lan vmtunnel0
2405
2406
2407# on 4.3.2.1
2408# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2409
2410qemu-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
2411
2412
2413@end example
2414
2415@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2416@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2417Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
2418listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2419and MODE @var{octalmode} to change default ownership and permissions for
2420communication port. This option is only available if QEMU has been compiled
2421with vde support enabled.
2422
2423Example:
2424@example
2425# launch vde switch
2426vde_switch -F -sock /tmp/myswitch
2427# launch QEMU instance
2428qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
2429@end example
2430
2431@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}]
2432
2433Create a hub port on QEMU "vlan" @var{hubid}.
2434
2435The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
2436netdev.  @code{-net} and @code{-device} with parameter @option{vlan} create the
2437required hub automatically. Alternatively, you can also connect the hubport
2438to another netdev with ID @var{nd} by using the @option{netdev=@var{nd}}
2439option.
2440
2441@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2442
2443Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2444be a unix domain socket backed one. The vhost-user uses a specifically defined
2445protocol to pass vhost ioctl replacement messages to an application on the other
2446end of the socket. On non-MSIX guests, the feature can be forced with
2447@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2448be created for multiqueue vhost-user.
2449
2450Example:
2451@example
2452qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2453     -numa node,memdev=mem \
2454     -chardev socket,id=chr0,path=/path/to/socket \
2455     -netdev type=vhost-user,id=net0,chardev=chr0 \
2456     -device virtio-net-pci,netdev=net0
2457@end example
2458
2459@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2460Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2461At most @var{len} bytes (64k by default) per packet are stored. The file format is
2462libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2463Note: For devices created with '-netdev', use '-object filter-dump,...' instead.
2464
2465@item -net none
2466Indicate that no network devices should be configured. It is used to
2467override the default configuration (@option{-net nic -net user}) which
2468is activated if no @option{-net} options are provided.
2469ETEXI
2470
2471STEXI
2472@end table
2473ETEXI
2474DEFHEADING()
2475
2476DEFHEADING(Character device options:)
2477
2478DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2479    "-chardev help\n"
2480    "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2481    "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2482    "         [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2483    "         [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2484    "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2485    "         [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2486    "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2487    "         [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2488    "         [,logfile=PATH][,logappend=on|off]\n"
2489    "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2490    "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2491    "         [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2492    "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2493    "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2494    "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2495#ifdef _WIN32
2496    "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2497    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2498#else
2499    "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2500    "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2501#endif
2502#ifdef CONFIG_BRLAPI
2503    "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2504#endif
2505#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2506        || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2507    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2508    "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2509#endif
2510#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2511    "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2512    "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2513#endif
2514#if defined(CONFIG_SPICE)
2515    "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2516    "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2517#endif
2518    , QEMU_ARCH_ALL
2519)
2520
2521STEXI
2522
2523The general form of a character device option is:
2524@table @option
2525@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2526@findex -chardev
2527Backend is one of:
2528@option{null},
2529@option{socket},
2530@option{udp},
2531@option{msmouse},
2532@option{vc},
2533@option{ringbuf},
2534@option{file},
2535@option{pipe},
2536@option{console},
2537@option{serial},
2538@option{pty},
2539@option{stdio},
2540@option{braille},
2541@option{tty},
2542@option{parallel},
2543@option{parport},
2544@option{spicevmc}.
2545@option{spiceport}.
2546The specific backend will determine the applicable options.
2547
2548Use @code{-chardev help} to print all available chardev backend types.
2549
2550All devices must have an id, which can be any string up to 127 characters long.
2551It is used to uniquely identify this device in other command line directives.
2552
2553A character device may be used in multiplexing mode by multiple front-ends.
2554Specify @option{mux=on} to enable this mode.
2555A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2556backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2557If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2558create a multiplexer with your specified ID, and you can then configure multiple
2559front ends to use that chardev ID for their input/output. Up to four different
2560front ends can be connected to a single multiplexed chardev. (Without
2561multiplexing enabled, a chardev can only be used by a single front end.)
2562For instance you could use this to allow a single stdio chardev to be used by
2563two serial ports and the QEMU monitor:
2564
2565@example
2566-chardev stdio,mux=on,id=char0 \
2567-mon chardev=char0,mode=readline \
2568-serial chardev:char0 \
2569-serial chardev:char0
2570@end example
2571
2572You can have more than one multiplexer in a system configuration; for instance
2573you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2574multiplexed between the QEMU monitor and a parallel port:
2575
2576@example
2577-chardev stdio,mux=on,id=char0 \
2578-mon chardev=char0,mode=readline \
2579-parallel chardev:char0 \
2580-chardev tcp,...,mux=on,id=char1 \
2581-serial chardev:char1 \
2582-serial chardev:char1
2583@end example
2584
2585When you're using a multiplexed character device, some escape sequences are
2586interpreted in the input. @xref{mux_keys, Keys in the character backend
2587multiplexer}.
2588
2589Note that some other command line options may implicitly create multiplexed
2590character backends; for instance @option{-serial mon:stdio} creates a
2591multiplexed stdio backend connected to the serial port and the QEMU monitor,
2592and @option{-nographic} also multiplexes the console and the monitor to
2593stdio.
2594
2595There is currently no support for multiplexing in the other direction
2596(where a single QEMU front end takes input and output from multiple chardevs).
2597
2598Every backend supports the @option{logfile} option, which supplies the path
2599to a file to record all data transmitted via the backend. The @option{logappend}
2600option controls whether the log file will be truncated or appended to when
2601opened.
2602
2603@end table
2604
2605The available backends are:
2606
2607@table @option
2608@item -chardev null ,id=@var{id}
2609A void device. This device will not emit any data, and will drop any data it
2610receives. The null backend does not take any options.
2611
2612@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2613
2614Create a two-way stream socket, which can be either a TCP or a unix socket. A
2615unix socket will be created if @option{path} is specified. Behaviour is
2616undefined if TCP options are specified for a unix socket.
2617
2618@option{server} specifies that the socket shall be a listening socket.
2619
2620@option{nowait} specifies that QEMU should not block waiting for a client to
2621connect to a listening socket.
2622
2623@option{telnet} specifies that traffic on the socket should interpret telnet
2624escape sequences.
2625
2626@option{reconnect} sets the timeout for reconnecting on non-server sockets when
2627the remote end goes away.  qemu will delay this many seconds and then attempt
2628to reconnect.  Zero disables reconnecting, and is the default.
2629
2630@option{tls-creds} requests enablement of the TLS protocol for encryption,
2631and specifies the id of the TLS credentials to use for the handshake. The
2632credentials must be previously created with the @option{-object tls-creds}
2633argument.
2634
2635TCP and unix socket options are given below:
2636
2637@table @option
2638
2639@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2640
2641@option{host} for a listening socket specifies the local address to be bound.
2642For a connecting socket species the remote host to connect to. @option{host} is
2643optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2644
2645@option{port} for a listening socket specifies the local port to be bound. For a
2646connecting socket specifies the port on the remote host to connect to.
2647@option{port} can be given as either a port number or a service name.
2648@option{port} is required.
2649
2650@option{to} is only relevant to listening sockets. If it is specified, and
2651@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2652to and including @option{to} until it succeeds. @option{to} must be specified
2653as a port number.
2654
2655@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2656If neither is specified the socket may use either protocol.
2657
2658@option{nodelay} disables the Nagle algorithm.
2659
2660@item unix options: path=@var{path}
2661
2662@option{path} specifies the local path of the unix socket. @option{path} is
2663required.
2664
2665@end table
2666
2667@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2668
2669Sends all traffic from the guest to a remote host over UDP.
2670
2671@option{host} specifies the remote host to connect to. If not specified it
2672defaults to @code{localhost}.
2673
2674@option{port} specifies the port on the remote host to connect to. @option{port}
2675is required.
2676
2677@option{localaddr} specifies the local address to bind to. If not specified it
2678defaults to @code{0.0.0.0}.
2679
2680@option{localport} specifies the local port to bind to. If not specified any
2681available local port will be used.
2682
2683@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2684If neither is specified the device may use either protocol.
2685
2686@item -chardev msmouse ,id=@var{id}
2687
2688Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2689take any options.
2690
2691@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2692
2693Connect to a QEMU text console. @option{vc} may optionally be given a specific
2694size.
2695
2696@option{width} and @option{height} specify the width and height respectively of
2697the console, in pixels.
2698
2699@option{cols} and @option{rows} specify that the console be sized to fit a text
2700console with the given dimensions.
2701
2702@item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2703
2704Create a ring buffer with fixed size @option{size}.
2705@var{size} must be a power of two and defaults to @code{64K}.
2706
2707@item -chardev file ,id=@var{id} ,path=@var{path}
2708
2709Log all traffic received from the guest to a file.
2710
2711@option{path} specifies the path of the file to be opened. This file will be
2712created if it does not already exist, and overwritten if it does. @option{path}
2713is required.
2714
2715@item -chardev pipe ,id=@var{id} ,path=@var{path}
2716
2717Create a two-way connection to the guest. The behaviour differs slightly between
2718Windows hosts and other hosts:
2719
2720On Windows, a single duplex pipe will be created at
2721@file{\\.pipe\@option{path}}.
2722
2723On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2724@file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2725received by the guest. Data written by the guest can be read from
2726@file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2727be present.
2728
2729@option{path} forms part of the pipe path as described above. @option{path} is
2730required.
2731
2732@item -chardev console ,id=@var{id}
2733
2734Send traffic from the guest to QEMU's standard output. @option{console} does not
2735take any options.
2736
2737@option{console} is only available on Windows hosts.
2738
2739@item -chardev serial ,id=@var{id} ,path=@option{path}
2740
2741Send traffic from the guest to a serial device on the host.
2742
2743On Unix hosts serial will actually accept any tty device,
2744not only serial lines.
2745
2746@option{path} specifies the name of the serial device to open.
2747
2748@item -chardev pty ,id=@var{id}
2749
2750Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2751not take any options.
2752
2753@option{pty} is not available on Windows hosts.
2754
2755@item -chardev stdio ,id=@var{id} [,signal=on|off]
2756Connect to standard input and standard output of the QEMU process.
2757
2758@option{signal} controls if signals are enabled on the terminal, that includes
2759exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2760default, use @option{signal=off} to disable it.
2761
2762@item -chardev braille ,id=@var{id}
2763
2764Connect to a local BrlAPI server. @option{braille} does not take any options.
2765
2766@item -chardev tty ,id=@var{id} ,path=@var{path}
2767
2768@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2769DragonFlyBSD hosts.  It is an alias for @option{serial}.
2770
2771@option{path} specifies the path to the tty. @option{path} is required.
2772
2773@item -chardev parallel ,id=@var{id} ,path=@var{path}
2774@itemx -chardev parport ,id=@var{id} ,path=@var{path}
2775
2776@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2777
2778Connect to a local parallel port.
2779
2780@option{path} specifies the path to the parallel port device. @option{path} is
2781required.
2782
2783@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2784
2785@option{spicevmc} is only available when spice support is built in.
2786
2787@option{debug} debug level for spicevmc
2788
2789@option{name} name of spice channel to connect to
2790
2791Connect to a spice virtual machine channel, such as vdiport.
2792
2793@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2794
2795@option{spiceport} is only available when spice support is built in.
2796
2797@option{debug} debug level for spicevmc
2798
2799@option{name} name of spice port to connect to
2800
2801Connect to a spice port, allowing a Spice client to handle the traffic
2802identified by a name (preferably a fqdn).
2803ETEXI
2804
2805STEXI
2806@end table
2807ETEXI
2808DEFHEADING()
2809
2810DEFHEADING(Bluetooth(R) options:)
2811STEXI
2812@table @option
2813ETEXI
2814
2815DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2816    "-bt hci,null    dumb bluetooth HCI - doesn't respond to commands\n" \
2817    "-bt hci,host[:id]\n" \
2818    "                use host's HCI with the given name\n" \
2819    "-bt hci[,vlan=n]\n" \
2820    "                emulate a standard HCI in virtual scatternet 'n'\n" \
2821    "-bt vhci[,vlan=n]\n" \
2822    "                add host computer to virtual scatternet 'n' using VHCI\n" \
2823    "-bt device:dev[,vlan=n]\n" \
2824    "                emulate a bluetooth device 'dev' in scatternet 'n'\n",
2825    QEMU_ARCH_ALL)
2826STEXI
2827@item -bt hci[...]
2828@findex -bt
2829Defines the function of the corresponding Bluetooth HCI.  -bt options
2830are matched with the HCIs present in the chosen machine type.  For
2831example when emulating a machine with only one HCI built into it, only
2832the first @code{-bt hci[...]} option is valid and defines the HCI's
2833logic.  The Transport Layer is decided by the machine type.  Currently
2834the machines @code{n800} and @code{n810} have one HCI and all other
2835machines have none.
2836
2837@anchor{bt-hcis}
2838The following three types are recognized:
2839
2840@table @option
2841@item -bt hci,null
2842(default) The corresponding Bluetooth HCI assumes no internal logic
2843and will not respond to any HCI commands or emit events.
2844
2845@item -bt hci,host[:@var{id}]
2846(@code{bluez} only) The corresponding HCI passes commands / events
2847to / from the physical HCI identified by the name @var{id} (default:
2848@code{hci0}) on the computer running QEMU.  Only available on @code{bluez}
2849capable systems like Linux.
2850
2851@item -bt hci[,vlan=@var{n}]
2852Add a virtual, standard HCI that will participate in the Bluetooth
2853scatternet @var{n} (default @code{0}).  Similarly to @option{-net}
2854VLANs, devices inside a bluetooth network @var{n} can only communicate
2855with other devices in the same network (scatternet).
2856@end table
2857
2858@item -bt vhci[,vlan=@var{n}]
2859(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2860to the host bluetooth stack instead of to the emulated target.  This
2861allows the host and target machines to participate in a common scatternet
2862and communicate.  Requires the Linux @code{vhci} driver installed.  Can
2863be used as following:
2864
2865@example
2866qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2867@end example
2868
2869@item -bt device:@var{dev}[,vlan=@var{n}]
2870Emulate a bluetooth device @var{dev} and place it in network @var{n}
2871(default @code{0}).  QEMU can only emulate one type of bluetooth devices
2872currently:
2873
2874@table @option
2875@item keyboard
2876Virtual wireless keyboard implementing the HIDP bluetooth profile.
2877@end table
2878ETEXI
2879
2880STEXI
2881@end table
2882ETEXI
2883DEFHEADING()
2884
2885#ifdef CONFIG_TPM
2886DEFHEADING(TPM device options:)
2887
2888DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2889    "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2890    "                use path to provide path to a character device; default is /dev/tpm0\n"
2891    "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2892    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n"
2893    "-tpmdev emulator,id=id,chardev=dev\n"
2894    "                configure the TPM device using chardev backend\n",
2895    QEMU_ARCH_ALL)
2896STEXI
2897
2898The general form of a TPM device option is:
2899@table @option
2900
2901@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2902@findex -tpmdev
2903
2904The specific backend type will determine the applicable options.
2905The @code{-tpmdev} option creates the TPM backend and requires a
2906@code{-device} option that specifies the TPM frontend interface model.
2907
2908Use @code{-tpmdev help} to print all available TPM backend types.
2909
2910@end table
2911
2912The available backends are:
2913
2914@table @option
2915
2916@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2917
2918(Linux-host only) Enable access to the host's TPM using the passthrough
2919driver.
2920
2921@option{path} specifies the path to the host's TPM device, i.e., on
2922a Linux host this would be @code{/dev/tpm0}.
2923@option{path} is optional and by default @code{/dev/tpm0} is used.
2924
2925@option{cancel-path} specifies the path to the host TPM device's sysfs
2926entry allowing for cancellation of an ongoing TPM command.
2927@option{cancel-path} is optional and by default QEMU will search for the
2928sysfs entry to use.
2929
2930Some notes about using the host's TPM with the passthrough driver:
2931
2932The TPM device accessed by the passthrough driver must not be
2933used by any other application on the host.
2934
2935Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2936the VM's firmware (BIOS/UEFI) will not be able to initialize the
2937TPM again and may therefore not show a TPM-specific menu that would
2938otherwise allow the user to configure the TPM, e.g., allow the user to
2939enable/disable or activate/deactivate the TPM.
2940Further, if TPM ownership is released from within a VM then the host's TPM
2941will get disabled and deactivated. To enable and activate the
2942TPM again afterwards, the host has to be rebooted and the user is
2943required to enter the firmware's menu to enable and activate the TPM.
2944If the TPM is left disabled and/or deactivated most TPM commands will fail.
2945
2946To create a passthrough TPM use the following two options:
2947@example
2948-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2949@end example
2950Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2951@code{tpmdev=tpm0} in the device option.
2952
2953@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
2954
2955(Linux-host only) Enable access to a TPM emulator using Unix domain socket based
2956chardev backend.
2957
2958@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
2959
2960To create a TPM emulator backend device with chardev socket backend:
2961@example
2962
2963-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
2964
2965@end example
2966
2967ETEXI
2968
2969STEXI
2970@end table
2971ETEXI
2972DEFHEADING()
2973
2974#endif
2975
2976DEFHEADING(Linux/Multiboot boot specific:)
2977STEXI
2978
2979When using these options, you can use a given Linux or Multiboot
2980kernel without installing it in the disk image. It can be useful
2981for easier testing of various kernels.
2982
2983@table @option
2984ETEXI
2985
2986DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2987    "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2988STEXI
2989@item -kernel @var{bzImage}
2990@findex -kernel
2991Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2992or in multiboot format.
2993ETEXI
2994
2995DEF("append", HAS_ARG, QEMU_OPTION_append, \
2996    "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2997STEXI
2998@item -append @var{cmdline}
2999@findex -append
3000Use @var{cmdline} as kernel command line
3001ETEXI
3002
3003DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
3004           "-initrd file    use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
3005STEXI
3006@item -initrd @var{file}
3007@findex -initrd
3008Use @var{file} as initial ram disk.
3009
3010@item -initrd "@var{file1} arg=foo,@var{file2}"
3011
3012This syntax is only available with multiboot.
3013
3014Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3015first module.
3016ETEXI
3017
3018DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
3019    "-dtb    file    use 'file' as device tree image\n", QEMU_ARCH_ALL)
3020STEXI
3021@item -dtb @var{file}
3022@findex -dtb
3023Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3024on boot.
3025ETEXI
3026
3027STEXI
3028@end table
3029ETEXI
3030DEFHEADING()
3031
3032DEFHEADING(Debug/Expert options:)
3033STEXI
3034@table @option
3035ETEXI
3036
3037DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
3038    "-fw_cfg [name=]<name>,file=<file>\n"
3039    "                add named fw_cfg entry with contents from file\n"
3040    "-fw_cfg [name=]<name>,string=<str>\n"
3041    "                add named fw_cfg entry with contents from string\n",
3042    QEMU_ARCH_ALL)
3043STEXI
3044
3045@item -fw_cfg [name=]@var{name},file=@var{file}
3046@findex -fw_cfg
3047Add named fw_cfg entry with contents from file @var{file}.
3048
3049@item -fw_cfg [name=]@var{name},string=@var{str}
3050Add named fw_cfg entry with contents from string @var{str}.
3051
3052The terminating NUL character of the contents of @var{str} will not be
3053included as part of the fw_cfg item data. To insert contents with
3054embedded NUL characters, you have to use the @var{file} parameter.
3055
3056The fw_cfg entries are passed by QEMU through to the guest.
3057
3058Example:
3059@example
3060    -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3061@end example
3062creates an fw_cfg entry named opt/com.mycompany/blob with contents
3063from ./my_blob.bin.
3064
3065ETEXI
3066
3067DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
3068    "-serial dev     redirect the serial port to char device 'dev'\n",
3069    QEMU_ARCH_ALL)
3070STEXI
3071@item -serial @var{dev}
3072@findex -serial
3073Redirect the virtual serial port to host character device
3074@var{dev}. The default device is @code{vc} in graphical mode and
3075@code{stdio} in non graphical mode.
3076
3077This option can be used several times to simulate up to 4 serial
3078ports.
3079
3080Use @code{-serial none} to disable all serial ports.
3081
3082Available character devices are:
3083@table @option
3084@item vc[:@var{W}x@var{H}]
3085Virtual console. Optionally, a width and height can be given in pixel with
3086@example
3087vc:800x600
3088@end example
3089It is also possible to specify width or height in characters:
3090@example
3091vc:80Cx24C
3092@end example
3093@item pty
3094[Linux only] Pseudo TTY (a new PTY is automatically allocated)
3095@item none
3096No device is allocated.
3097@item null
3098void device
3099@item chardev:@var{id}
3100Use a named character device defined with the @code{-chardev} option.
3101@item /dev/XXX
3102[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3103parameters are set according to the emulated ones.
3104@item /dev/parport@var{N}
3105[Linux only, parallel port only] Use host parallel port
3106@var{N}. Currently SPP and EPP parallel port features can be used.
3107@item file:@var{filename}
3108Write output to @var{filename}. No character can be read.
3109@item stdio
3110[Unix only] standard input/output
3111@item pipe:@var{filename}
3112name pipe @var{filename}
3113@item COM@var{n}
3114[Windows only] Use host serial port @var{n}
3115@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3116This implements UDP Net Console.
3117When @var{remote_host} or @var{src_ip} are not specified
3118they default to @code{0.0.0.0}.
3119When not using a specified @var{src_port} a random port is automatically chosen.
3120
3121If you just want a simple readonly console you can use @code{netcat} or
3122@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3123@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3124will appear in the netconsole session.
3125
3126If you plan to send characters back via netconsole or you want to stop
3127and start QEMU a lot of times, you should have QEMU use the same
3128source port each time by using something like @code{-serial
3129udp::4555@@:4556} to QEMU. Another approach is to use a patched
3130version of netcat which can listen to a TCP port and send and receive
3131characters via udp.  If you have a patched version of netcat which
3132activates telnet remote echo and single char transfer, then you can
3133use the following options to set up a netcat redirector to allow
3134telnet on port 5555 to access the QEMU port.
3135@table @code
3136@item QEMU Options:
3137-serial udp::4555@@:4556
3138@item netcat options:
3139-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3140@item telnet options:
3141localhost 5555
3142@end table
3143
3144@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3145The TCP Net Console has two modes of operation.  It can send the serial
3146I/O to a location or wait for a connection from a location.  By default
3147the TCP Net Console is sent to @var{host} at the @var{port}.  If you use
3148the @var{server} option QEMU will wait for a client socket application
3149to connect to the port before continuing, unless the @code{nowait}
3150option was specified.  The @code{nodelay} option disables the Nagle buffering
3151algorithm.  The @code{reconnect} option only applies if @var{noserver} is
3152set, if the connection goes down it will attempt to reconnect at the
3153given interval.  If @var{host} is omitted, 0.0.0.0 is assumed. Only
3154one TCP connection at a time is accepted. You can use @code{telnet} to
3155connect to the corresponding character device.
3156@table @code
3157@item Example to send tcp console to 192.168.0.2 port 4444
3158-serial tcp:192.168.0.2:4444
3159@item Example to listen and wait on port 4444 for connection
3160-serial tcp::4444,server
3161@item Example to not wait and listen on ip 192.168.0.100 port 4444
3162-serial tcp:192.168.0.100:4444,server,nowait
3163@end table
3164
3165@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3166The telnet protocol is used instead of raw tcp sockets.  The options
3167work the same as if you had specified @code{-serial tcp}.  The
3168difference is that the port acts like a telnet server or client using
3169telnet option negotiation.  This will also allow you to send the
3170MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3171sequence.  Typically in unix telnet you do it with Control-] and then
3172type "send break" followed by pressing the enter key.
3173
3174@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3175A unix domain socket is used instead of a tcp socket.  The option works the
3176same as if you had specified @code{-serial tcp} except the unix domain socket
3177@var{path} is used for connections.
3178
3179@item mon:@var{dev_string}
3180This is a special option to allow the monitor to be multiplexed onto
3181another serial port.  The monitor is accessed with key sequence of
3182@key{Control-a} and then pressing @key{c}.
3183@var{dev_string} should be any one of the serial devices specified
3184above.  An example to multiplex the monitor onto a telnet server
3185listening on port 4444 would be:
3186@table @code
3187@item -serial mon:telnet::4444,server,nowait
3188@end table
3189When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3190QEMU any more but will be passed to the guest instead.
3191
3192@item braille
3193Braille device.  This will use BrlAPI to display the braille output on a real
3194or fake device.
3195
3196@item msmouse
3197Three button serial mouse. Configure the guest to use Microsoft protocol.
3198@end table
3199ETEXI
3200
3201DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3202    "-parallel dev   redirect the parallel port to char device 'dev'\n",
3203    QEMU_ARCH_ALL)
3204STEXI
3205@item -parallel @var{dev}
3206@findex -parallel
3207Redirect the virtual parallel port to host device @var{dev} (same
3208devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3209be used to use hardware devices connected on the corresponding host
3210parallel port.
3211
3212This option can be used several times to simulate up to 3 parallel
3213ports.
3214
3215Use @code{-parallel none} to disable all parallel ports.
3216ETEXI
3217
3218DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3219    "-monitor dev    redirect the monitor to char device 'dev'\n",
3220    QEMU_ARCH_ALL)
3221STEXI
3222@item -monitor @var{dev}
3223@findex -monitor
3224Redirect the monitor to host device @var{dev} (same devices as the
3225serial port).
3226The default device is @code{vc} in graphical mode and @code{stdio} in
3227non graphical mode.
3228Use @code{-monitor none} to disable the default monitor.
3229ETEXI
3230DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3231    "-qmp dev        like -monitor but opens in 'control' mode\n",
3232    QEMU_ARCH_ALL)
3233STEXI
3234@item -qmp @var{dev}
3235@findex -qmp
3236Like -monitor but opens in 'control' mode.
3237ETEXI
3238DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3239    "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3240    QEMU_ARCH_ALL)
3241STEXI
3242@item -qmp-pretty @var{dev}
3243@findex -qmp-pretty
3244Like -qmp but uses pretty JSON formatting.
3245ETEXI
3246
3247DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3248    "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL)
3249STEXI
3250@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]
3251@findex -mon
3252Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing
3253easing human reading and debugging.
3254ETEXI
3255
3256DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3257    "-debugcon dev   redirect the debug console to char device 'dev'\n",
3258    QEMU_ARCH_ALL)
3259STEXI
3260@item -debugcon @var{dev}
3261@findex -debugcon
3262Redirect the debug console to host device @var{dev} (same devices as the
3263serial port).  The debug console is an I/O port which is typically port
32640xe9; writing to that I/O port sends output to this device.
3265The default device is @code{vc} in graphical mode and @code{stdio} in
3266non graphical mode.
3267ETEXI
3268
3269DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3270    "-pidfile file   write PID to 'file'\n", QEMU_ARCH_ALL)
3271STEXI
3272@item -pidfile @var{file}
3273@findex -pidfile
3274Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3275from a script.
3276ETEXI
3277
3278DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3279    "-singlestep     always run in singlestep mode\n", QEMU_ARCH_ALL)
3280STEXI
3281@item -singlestep
3282@findex -singlestep
3283Run the emulation in single step mode.
3284ETEXI
3285
3286DEF("S", 0, QEMU_OPTION_S, \
3287    "-S              freeze CPU at startup (use 'c' to start execution)\n",
3288    QEMU_ARCH_ALL)
3289STEXI
3290@item -S
3291@findex -S
3292Do not start CPU at startup (you must type 'c' in the monitor).
3293ETEXI
3294
3295DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3296    "-realtime [mlock=on|off]\n"
3297    "                run qemu with realtime features\n"
3298    "                mlock=on|off controls mlock support (default: on)\n",
3299    QEMU_ARCH_ALL)
3300STEXI
3301@item -realtime mlock=on|off
3302@findex -realtime
3303Run qemu with realtime features.
3304mlocking qemu and guest memory can be enabled via @option{mlock=on}
3305(enabled by default).
3306ETEXI
3307
3308DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3309    "-gdb dev        wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3310STEXI
3311@item -gdb @var{dev}
3312@findex -gdb
3313Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3314connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3315stdio are reasonable use case. The latter is allowing to start QEMU from
3316within gdb and establish the connection via a pipe:
3317@example
3318(gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3319@end example
3320ETEXI
3321
3322DEF("s", 0, QEMU_OPTION_s, \
3323    "-s              shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3324    QEMU_ARCH_ALL)
3325STEXI
3326@item -s
3327@findex -s
3328Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3329(@pxref{gdb_usage}).
3330ETEXI
3331
3332DEF("d", HAS_ARG, QEMU_OPTION_d, \
3333    "-d item1,...    enable logging of specified items (use '-d help' for a list of log items)\n",
3334    QEMU_ARCH_ALL)
3335STEXI
3336@item -d @var{item1}[,...]
3337@findex -d
3338Enable logging of specified items. Use '-d help' for a list of log items.
3339ETEXI
3340
3341DEF("D", HAS_ARG, QEMU_OPTION_D, \
3342    "-D logfile      output log to logfile (default stderr)\n",
3343    QEMU_ARCH_ALL)
3344STEXI
3345@item -D @var{logfile}
3346@findex -D
3347Output log in @var{logfile} instead of to stderr
3348ETEXI
3349
3350DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3351    "-dfilter range,..  filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3352    QEMU_ARCH_ALL)
3353STEXI
3354@item -dfilter @var{range1}[,...]
3355@findex -dfilter
3356Filter debug output to that relevant to a range of target addresses. The filter
3357spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3358@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3359addresses and sizes required. For example:
3360@example
3361    -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3362@end example
3363Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3364the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3365block starting at 0xffffffc00005f000.
3366ETEXI
3367
3368DEF("L", HAS_ARG, QEMU_OPTION_L, \
3369    "-L path         set the directory for the BIOS, VGA BIOS and keymaps\n",
3370    QEMU_ARCH_ALL)
3371STEXI
3372@item -L  @var{path}
3373@findex -L
3374Set the directory for the BIOS, VGA BIOS and keymaps.
3375
3376To list all the data directories, use @code{-L help}.
3377ETEXI
3378
3379DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3380    "-bios file      set the filename for the BIOS\n", QEMU_ARCH_ALL)
3381STEXI
3382@item -bios @var{file}
3383@findex -bios
3384Set the filename for the BIOS.
3385ETEXI
3386
3387DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3388    "-enable-kvm     enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3389STEXI
3390@item -enable-kvm
3391@findex -enable-kvm
3392Enable KVM full virtualization support. This option is only available
3393if KVM support is enabled when compiling.
3394ETEXI
3395
3396DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3397    "-enable-hax     enable HAX virtualization support\n", QEMU_ARCH_I386)
3398STEXI
3399@item -enable-hax
3400@findex -enable-hax
3401Enable HAX (Hardware-based Acceleration eXecution) support. This option
3402is only available if HAX support is enabled when compiling. HAX is only
3403applicable to MAC and Windows platform, and thus does not conflict with
3404KVM.
3405ETEXI
3406
3407DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3408    "-xen-domid id   specify xen guest domain id\n", QEMU_ARCH_ALL)
3409DEF("xen-create", 0, QEMU_OPTION_xen_create,
3410    "-xen-create     create domain using xen hypercalls, bypassing xend\n"
3411    "                warning: should not be used when xend is in use\n",
3412    QEMU_ARCH_ALL)
3413DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3414    "-xen-attach     attach to existing xen domain\n"
3415    "                xend will use this when starting QEMU\n",
3416    QEMU_ARCH_ALL)
3417DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
3418    "-xen-domid-restrict     restrict set of available xen operations\n"
3419    "                        to specified domain id. (Does not affect\n"
3420    "                        xenpv machine type).\n",
3421    QEMU_ARCH_ALL)
3422STEXI
3423@item -xen-domid @var{id}
3424@findex -xen-domid
3425Specify xen guest domain @var{id} (XEN only).
3426@item -xen-create
3427@findex -xen-create
3428Create domain using xen hypercalls, bypassing xend.
3429Warning: should not be used when xend is in use (XEN only).
3430@item -xen-attach
3431@findex -xen-attach
3432Attach to existing xen domain.
3433xend will use this when starting QEMU (XEN only).
3434@findex -xen-domid-restrict
3435Restrict set of available xen operations to specified domain id (XEN only).
3436ETEXI
3437
3438DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3439    "-no-reboot      exit instead of rebooting\n", QEMU_ARCH_ALL)
3440STEXI
3441@item -no-reboot
3442@findex -no-reboot
3443Exit instead of rebooting.
3444ETEXI
3445
3446DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3447    "-no-shutdown    stop before shutdown\n", QEMU_ARCH_ALL)
3448STEXI
3449@item -no-shutdown
3450@findex -no-shutdown
3451Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3452This allows for instance switching to monitor to commit changes to the
3453disk image.
3454ETEXI
3455
3456DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3457    "-loadvm [tag|id]\n" \
3458    "                start right away with a saved state (loadvm in monitor)\n",
3459    QEMU_ARCH_ALL)
3460STEXI
3461@item -loadvm @var{file}
3462@findex -loadvm
3463Start right away with a saved state (@code{loadvm} in monitor)
3464ETEXI
3465
3466#ifndef _WIN32
3467DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3468    "-daemonize      daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3469#endif
3470STEXI
3471@item -daemonize
3472@findex -daemonize
3473Daemonize the QEMU process after initialization.  QEMU will not detach from
3474standard IO until it is ready to receive connections on any of its devices.
3475This option is a useful way for external programs to launch QEMU without having
3476to cope with initialization race conditions.
3477ETEXI
3478
3479DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3480    "-option-rom rom load a file, rom, into the option ROM space\n",
3481    QEMU_ARCH_ALL)
3482STEXI
3483@item -option-rom @var{file}
3484@findex -option-rom
3485Load the contents of @var{file} as an option ROM.
3486This option is useful to load things like EtherBoot.
3487ETEXI
3488
3489HXCOMM Silently ignored for compatibility
3490DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3491
3492HXCOMM Options deprecated by -rtc
3493DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3494DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3495
3496DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3497    "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3498    "                set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3499    QEMU_ARCH_ALL)
3500
3501STEXI
3502
3503@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3504@findex -rtc
3505Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3506UTC or local time, respectively. @code{localtime} is required for correct date in
3507MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3508format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3509
3510By default the RTC is driven by the host system time. This allows using of the
3511RTC as accurate reference clock inside the guest, specifically if the host
3512time is smoothly following an accurate external reference clock, e.g. via NTP.
3513If you want to isolate the guest time from the host, you can set @option{clock}
3514to @code{rt} instead.  To even prevent it from progressing during suspension,
3515you can set it to @code{vm}.
3516
3517Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3518specifically with Windows' ACPI HAL. This option will try to figure out how
3519many timer interrupts were not processed by the Windows guest and will
3520re-inject them.
3521ETEXI
3522
3523DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3524    "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3525    "                enable virtual instruction counter with 2^N clock ticks per\n" \
3526    "                instruction, enable aligning the host and virtual clocks\n" \
3527    "                or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3528STEXI
3529@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3530@findex -icount
3531Enable virtual instruction counter.  The virtual cpu will execute one
3532instruction every 2^@var{N} ns of virtual time.  If @code{auto} is specified
3533then the virtual cpu speed will be automatically adjusted to keep virtual
3534time within a few seconds of real time.
3535
3536When the virtual cpu is sleeping, the virtual time will advance at default
3537speed unless @option{sleep=on|off} is specified.
3538With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3539instantly whenever the virtual cpu goes to sleep mode and will not advance
3540if no timer is enabled. This behavior give deterministic execution times from
3541the guest point of view.
3542
3543Note that while this option can give deterministic behavior, it does not
3544provide cycle accurate emulation.  Modern CPUs contain superscalar out of
3545order cores with complex cache hierarchies.  The number of instructions
3546executed often has little or no correlation with actual performance.
3547
3548@option{align=on} will activate the delay algorithm which will try
3549to synchronise the host clock and the virtual clock. The goal is to
3550have a guest running at the real frequency imposed by the shift option.
3551Whenever the guest clock is behind the host clock and if
3552@option{align=on} is specified then we print a message to the user
3553to inform about the delay.
3554Currently this option does not work when @option{shift} is @code{auto}.
3555Note: The sync algorithm will work for those shift values for which
3556the guest clock runs ahead of the host clock. Typically this happens
3557when the shift value is high (how high depends on the host machine).
3558
3559When @option{rr} option is specified deterministic record/replay is enabled.
3560Replay log is written into @var{filename} file in record mode and
3561read from this file in replay mode.
3562
3563Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3564at the start of execution recording. In replay mode this option is used
3565to load the initial VM state.
3566ETEXI
3567
3568DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3569    "-watchdog model\n" \
3570    "                enable virtual hardware watchdog [default=none]\n",
3571    QEMU_ARCH_ALL)
3572STEXI
3573@item -watchdog @var{model}
3574@findex -watchdog
3575Create a virtual hardware watchdog device.  Once enabled (by a guest
3576action), the watchdog must be periodically polled by an agent inside
3577the guest or else the guest will be restarted. Choose a model for
3578which your guest has drivers.
3579
3580The @var{model} is the model of hardware watchdog to emulate. Use
3581@code{-watchdog help} to list available hardware models. Only one
3582watchdog can be enabled for a guest.
3583
3584The following models may be available:
3585@table @option
3586@item ib700
3587iBASE 700 is a very simple ISA watchdog with a single timer.
3588@item i6300esb
3589Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3590dual-timer watchdog.
3591@item diag288
3592A virtual watchdog for s390x backed by the diagnose 288 hypercall
3593(currently KVM only).
3594@end table
3595ETEXI
3596
3597DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3598    "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \
3599    "                action when watchdog fires [default=reset]\n",
3600    QEMU_ARCH_ALL)
3601STEXI
3602@item -watchdog-action @var{action}
3603@findex -watchdog-action
3604
3605The @var{action} controls what QEMU will do when the watchdog timer
3606expires.
3607The default is
3608@code{reset} (forcefully reset the guest).
3609Other possible actions are:
3610@code{shutdown} (attempt to gracefully shutdown the guest),
3611@code{poweroff} (forcefully poweroff the guest),
3612@code{inject-nmi} (inject a NMI into the guest),
3613@code{pause} (pause the guest),
3614@code{debug} (print a debug message and continue), or
3615@code{none} (do nothing).
3616
3617Note that the @code{shutdown} action requires that the guest responds
3618to ACPI signals, which it may not be able to do in the sort of
3619situations where the watchdog would have expired, and thus
3620@code{-watchdog-action shutdown} is not recommended for production use.
3621
3622Examples:
3623
3624@table @code
3625@item -watchdog i6300esb -watchdog-action pause
3626@itemx -watchdog ib700
3627@end table
3628ETEXI
3629
3630DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3631    "-echr chr       set terminal escape character instead of ctrl-a\n",
3632    QEMU_ARCH_ALL)
3633STEXI
3634
3635@item -echr @var{numeric_ascii_value}
3636@findex -echr
3637Change the escape character used for switching to the monitor when using
3638monitor and serial sharing.  The default is @code{0x01} when using the
3639@code{-nographic} option.  @code{0x01} is equal to pressing
3640@code{Control-a}.  You can select a different character from the ascii
3641control keys where 1 through 26 map to Control-a through Control-z.  For
3642instance you could use the either of the following to change the escape
3643character to Control-t.
3644@table @code
3645@item -echr 0x14
3646@itemx -echr 20
3647@end table
3648ETEXI
3649
3650DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3651    "-virtioconsole c\n" \
3652    "                set virtio console\n", QEMU_ARCH_ALL)
3653STEXI
3654@item -virtioconsole @var{c}
3655@findex -virtioconsole
3656Set virtio console.
3657
3658This option is maintained for backward compatibility.
3659
3660Please use @code{-device virtconsole} for the new way of invocation.
3661ETEXI
3662
3663DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3664    "-show-cursor    show cursor\n", QEMU_ARCH_ALL)
3665STEXI
3666@item -show-cursor
3667@findex -show-cursor
3668Show cursor.
3669ETEXI
3670
3671DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3672    "-tb-size n      set TB size\n", QEMU_ARCH_ALL)
3673STEXI
3674@item -tb-size @var{n}
3675@findex -tb-size
3676Set TB size.
3677ETEXI
3678
3679DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3680    "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3681    "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3682    "-incoming unix:socketpath\n" \
3683    "                prepare for incoming migration, listen on\n" \
3684    "                specified protocol and socket address\n" \
3685    "-incoming fd:fd\n" \
3686    "-incoming exec:cmdline\n" \
3687    "                accept incoming migration on given file descriptor\n" \
3688    "                or from given external command\n" \
3689    "-incoming defer\n" \
3690    "                wait for the URI to be specified via migrate_incoming\n",
3691    QEMU_ARCH_ALL)
3692STEXI
3693@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3694@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3695@findex -incoming
3696Prepare for incoming migration, listen on a given tcp port.
3697
3698@item -incoming unix:@var{socketpath}
3699Prepare for incoming migration, listen on a given unix socket.
3700
3701@item -incoming fd:@var{fd}
3702Accept incoming migration from a given filedescriptor.
3703
3704@item -incoming exec:@var{cmdline}
3705Accept incoming migration as an output from specified external command.
3706
3707@item -incoming defer
3708Wait for the URI to be specified via migrate_incoming.  The monitor can
3709be used to change settings (such as migration parameters) prior to issuing
3710the migrate_incoming to allow the migration to begin.
3711ETEXI
3712
3713DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \
3714    "-only-migratable     allow only migratable devices\n", QEMU_ARCH_ALL)
3715STEXI
3716@item -only-migratable
3717@findex -only-migratable
3718Only allow migratable devices. Devices will not be allowed to enter an
3719unmigratable state.
3720ETEXI
3721
3722DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3723    "-nodefaults     don't create default devices\n", QEMU_ARCH_ALL)
3724STEXI
3725@item -nodefaults
3726@findex -nodefaults
3727Don't create default devices. Normally, QEMU sets the default devices like serial
3728port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3729CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3730default devices.
3731ETEXI
3732
3733#ifndef _WIN32
3734DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3735    "-chroot dir     chroot to dir just before starting the VM\n",
3736    QEMU_ARCH_ALL)
3737#endif
3738STEXI
3739@item -chroot @var{dir}
3740@findex -chroot
3741Immediately before starting guest execution, chroot to the specified
3742directory.  Especially useful in combination with -runas.
3743ETEXI
3744
3745#ifndef _WIN32
3746DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3747    "-runas user     change to user id user just before starting the VM\n",
3748    QEMU_ARCH_ALL)
3749#endif
3750STEXI
3751@item -runas @var{user}
3752@findex -runas
3753Immediately before starting guest execution, drop root privileges, switching
3754to the specified user.
3755ETEXI
3756
3757DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3758    "-prom-env variable=value\n"
3759    "                set OpenBIOS nvram variables\n",
3760    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3761STEXI
3762@item -prom-env @var{variable}=@var{value}
3763@findex -prom-env
3764Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3765ETEXI
3766DEF("semihosting", 0, QEMU_OPTION_semihosting,
3767    "-semihosting    semihosting mode\n",
3768    QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3769    QEMU_ARCH_MIPS)
3770STEXI
3771@item -semihosting
3772@findex -semihosting
3773Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3774ETEXI
3775DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3776    "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3777    "                semihosting configuration\n",
3778QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3779QEMU_ARCH_MIPS)
3780STEXI
3781@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3782@findex -semihosting-config
3783Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3784@table @option
3785@item target=@code{native|gdb|auto}
3786Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3787or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3788during debug sessions and @code{native} otherwise.
3789@item arg=@var{str1},arg=@var{str2},...
3790Allows the user to pass input arguments, and can be used multiple times to build
3791up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3792command line is still supported for backward compatibility. If both the
3793@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3794specified, the former is passed to semihosting as it always takes precedence.
3795@end table
3796ETEXI
3797DEF("old-param", 0, QEMU_OPTION_old_param,
3798    "-old-param      old param mode\n", QEMU_ARCH_ARM)
3799STEXI
3800@item -old-param
3801@findex -old-param (ARM)
3802Old param mode (ARM only).
3803ETEXI
3804
3805DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3806    "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
3807    "          [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
3808    "                Enable seccomp mode 2 system call filter (default 'off').\n" \
3809    "                use 'obsolete' to allow obsolete system calls that are provided\n" \
3810    "                    by the kernel, but typically no longer used by modern\n" \
3811    "                    C library implementations.\n" \
3812    "                use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \
3813    "                    its privileges by blacklisting all set*uid|gid system calls.\n" \
3814    "                    The value 'children' will deny set*uid|gid system calls for\n" \
3815    "                    main QEMU process but will allow forks and execves to run unprivileged\n" \
3816    "                use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \
3817    "                     blacklisting *fork and execve\n" \
3818    "                use 'resourcecontrol' to disable process affinity and schedular priority\n",
3819    QEMU_ARCH_ALL)
3820STEXI
3821@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
3822@findex -sandbox
3823Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3824disable it.  The default is 'off'.
3825@table @option
3826@item obsolete=@var{string}
3827Enable Obsolete system calls
3828@item elevateprivileges=@var{string}
3829Disable set*uid|gid system calls
3830@item spawn=@var{string}
3831Disable *fork and execve
3832@item resourcecontrol=@var{string}
3833Disable process affinity and schedular priority
3834@end table
3835ETEXI
3836
3837DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3838    "-readconfig <file>\n", QEMU_ARCH_ALL)
3839STEXI
3840@item -readconfig @var{file}
3841@findex -readconfig
3842Read device configuration from @var{file}. This approach is useful when you want to spawn
3843QEMU process with many command line options but you don't want to exceed the command line
3844character limit.
3845ETEXI
3846DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3847    "-writeconfig <file>\n"
3848    "                read/write config file\n", QEMU_ARCH_ALL)
3849STEXI
3850@item -writeconfig @var{file}
3851@findex -writeconfig
3852Write device configuration to @var{file}. The @var{file} can be either filename to save
3853command line and device configuration into file or dash @code{-}) character to print the
3854output to stdout. This can be later used as input file for @code{-readconfig} option.
3855ETEXI
3856HXCOMM Deprecated, same as -no-user-config
3857DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
3858DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3859    "-no-user-config\n"
3860    "                do not load default user-provided config files at startup\n",
3861    QEMU_ARCH_ALL)
3862STEXI
3863@item -no-user-config
3864@findex -no-user-config
3865The @code{-no-user-config} option makes QEMU not load any of the user-provided
3866config files on @var{sysconfdir}.
3867ETEXI
3868DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3869    "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3870    "                specify tracing options\n",
3871    QEMU_ARCH_ALL)
3872STEXI
3873HXCOMM This line is not accurate, as some sub-options are backend-specific but
3874HXCOMM HX does not support conditional compilation of text.
3875@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
3876@findex -trace
3877@include qemu-option-trace.texi
3878ETEXI
3879
3880HXCOMM Internal use
3881DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3882DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3883
3884#ifdef __linux__
3885DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3886    "-enable-fips    enable FIPS 140-2 compliance\n",
3887    QEMU_ARCH_ALL)
3888#endif
3889STEXI
3890@item -enable-fips
3891@findex -enable-fips
3892Enable FIPS 140-2 compliance mode.
3893ETEXI
3894
3895HXCOMM Deprecated by -machine accel=tcg property
3896DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3897
3898HXCOMM Deprecated by kvm-pit driver properties
3899DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3900    "", QEMU_ARCH_I386)
3901
3902HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3903DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3904
3905HXCOMM Deprecated (ignored)
3906DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3907
3908DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3909    "-msg timestamp[=on|off]\n"
3910    "                change the format of messages\n"
3911    "                on|off controls leading timestamps (default:on)\n",
3912    QEMU_ARCH_ALL)
3913STEXI
3914@item -msg timestamp[=on|off]
3915@findex -msg
3916prepend a timestamp to each log message.(default:on)
3917ETEXI
3918
3919DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3920    "-dump-vmstate <file>\n"
3921    "                Output vmstate information in JSON format to file.\n"
3922    "                Use the scripts/vmstate-static-checker.py file to\n"
3923    "                check for possible regressions in migration code\n"
3924    "                by comparing two such vmstate dumps.\n",
3925    QEMU_ARCH_ALL)
3926STEXI
3927@item -dump-vmstate @var{file}
3928@findex -dump-vmstate
3929Dump json-encoded vmstate information for current machine type to file
3930in @var{file}
3931ETEXI
3932
3933STEXI
3934@end table
3935ETEXI
3936DEFHEADING()
3937
3938DEFHEADING(Generic object creation:)
3939STEXI
3940@table @option
3941ETEXI
3942
3943DEF("object", HAS_ARG, QEMU_OPTION_object,
3944    "-object TYPENAME[,PROP1=VALUE1,...]\n"
3945    "                create a new object of type TYPENAME setting properties\n"
3946    "                in the order they are specified.  Note that the 'id'\n"
3947    "                property must be set.  These objects are placed in the\n"
3948    "                '/objects' path.\n",
3949    QEMU_ARCH_ALL)
3950STEXI
3951@item -object @var{typename}[,@var{prop1}=@var{value1},...]
3952@findex -object
3953Create a new object of type @var{typename} setting properties
3954in the order they are specified.  Note that the 'id'
3955property must be set.  These objects are placed in the
3956'/objects' path.
3957
3958@table @option
3959
3960@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}
3961
3962Creates a memory file backend object, which can be used to back
3963the guest RAM with huge pages.
3964
3965The @option{id} parameter is a unique ID that will be used to reference this
3966memory region when configuring the @option{-numa} argument.
3967
3968The @option{size} option provides the size of the memory region, and accepts
3969common suffixes, eg @option{500M}.
3970
3971The @option{mem-path} provides the path to either a shared memory or huge page
3972filesystem mount.
3973
3974The @option{share} boolean option determines whether the memory
3975region is marked as private to QEMU, or shared. The latter allows
3976a co-operating external process to access the QEMU memory region.
3977
3978Setting the @option{discard-data} boolean option to @var{on}
3979indicates that file contents can be destroyed when QEMU exits,
3980to avoid unnecessarily flushing data to the backing file.  Note
3981that @option{discard-data} is only an optimization, and QEMU
3982might not discard file contents if it aborts unexpectedly or is
3983terminated using SIGKILL.
3984
3985The @option{merge} boolean option enables memory merge, also known as
3986MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for
3987memory deduplication.
3988
3989Setting the @option{dump} boolean option to @var{off} excludes the memory from
3990core dumps. This feature is also known as MADV_DONTDUMP.
3991
3992The @option{prealloc} boolean option enables memory preallocation.
3993
3994The @option{host-nodes} option binds the memory range to a list of NUMA host
3995nodes.
3996
3997The @option{policy} option sets the NUMA policy to one of the following values:
3998
3999@table @option
4000@item @var{default}
4001default host policy
4002
4003@item @var{preferred}
4004prefer the given host node list for allocation
4005
4006@item @var{bind}
4007restrict memory allocation to the given host node list
4008
4009@item @var{interleave}
4010interleave memory allocations across the given host node list
4011@end table
4012
4013The @option{align} option specifies the base address alignment when
4014QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg
4015@option{2M}. Some backend store specified by @option{mem-path}
4016requires an alignment different than the default one used by QEMU, eg
4017the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In
4018such cases, users can specify the required alignment via this option.
4019
4020@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}
4021
4022Creates a memory backend object, which can be used to back the guest RAM.
4023Memory backend objects offer more control than the @option{-m} option that is
4024traditionally used to define guest RAM. Please refer to
4025@option{memory-backend-file} for a description of the options.
4026
4027@item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size}
4028
4029Creates an anonymous memory file backend object, which allows QEMU to
4030share the memory with an external process (e.g. when using
4031vhost-user). The memory is allocated with memfd and optional
4032sealing. (Linux only)
4033
4034The @option{seal} option creates a sealed-file, that will block
4035further resizing the memory ('on' by default).
4036
4037The @option{hugetlb} option specify the file to be created resides in
4038the hugetlbfs filesystem (since Linux 4.14).  Used in conjunction with
4039the @option{hugetlb} option, the @option{hugetlbsize} option specify
4040the hugetlb page size on systems that support multiple hugetlb page
4041sizes (it must be a power of 2 value supported by the system).
4042
4043In some versions of Linux, the @option{hugetlb} option is incompatible
4044with the @option{seal} option (requires at least Linux 4.16).
4045
4046Please refer to @option{memory-backend-file} for a description of the
4047other options.
4048
4049@item -object rng-random,id=@var{id},filename=@var{/dev/random}
4050
4051Creates a random number generator backend which obtains entropy from
4052a device on the host. The @option{id} parameter is a unique ID that
4053will be used to reference this entropy backend from the @option{virtio-rng}
4054device. The @option{filename} parameter specifies which file to obtain
4055entropy from and if omitted defaults to @option{/dev/random}.
4056
4057@item -object rng-egd,id=@var{id},chardev=@var{chardevid}
4058
4059Creates a random number generator backend which obtains entropy from
4060an external daemon running on the host. The @option{id} parameter is
4061a unique ID that will be used to reference this entropy backend from
4062the @option{virtio-rng} device. The @option{chardev} parameter is
4063the unique ID of a character device backend that provides the connection
4064to the RNG daemon.
4065
4066@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
4067
4068Creates a TLS anonymous credentials object, which can be used to provide
4069TLS support on network backends. The @option{id} parameter is a unique
4070ID which network backends will use to access the credentials. The
4071@option{endpoint} is either @option{server} or @option{client} depending
4072on whether the QEMU network backend that uses the credentials will be
4073acting as a client or as a server. If @option{verify-peer} is enabled
4074(the default) then once the handshake is completed, the peer credentials
4075will be verified, though this is a no-op for anonymous credentials.
4076
4077The @var{dir} parameter tells QEMU where to find the credential
4078files. For server endpoints, this directory may contain a file
4079@var{dh-params.pem} providing diffie-hellman parameters to use
4080for the TLS server. If the file is missing, QEMU will generate
4081a set of DH parameters at startup. This is a computationally
4082expensive operation that consumes random pool entropy, so it is
4083recommended that a persistent set of parameters be generated
4084upfront and saved.
4085
4086@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}
4087
4088Creates a TLS anonymous credentials object, which can be used to provide
4089TLS support on network backends. The @option{id} parameter is a unique
4090ID which network backends will use to access the credentials. The
4091@option{endpoint} is either @option{server} or @option{client} depending
4092on whether the QEMU network backend that uses the credentials will be
4093acting as a client or as a server. If @option{verify-peer} is enabled
4094(the default) then once the handshake is completed, the peer credentials
4095will be verified. With x509 certificates, this implies that the clients
4096must be provided with valid client certificates too.
4097
4098The @var{dir} parameter tells QEMU where to find the credential
4099files. For server endpoints, this directory may contain a file
4100@var{dh-params.pem} providing diffie-hellman parameters to use
4101for the TLS server. If the file is missing, QEMU will generate
4102a set of DH parameters at startup. This is a computationally
4103expensive operation that consumes random pool entropy, so it is
4104recommended that a persistent set of parameters be generated
4105upfront and saved.
4106
4107For x509 certificate credentials the directory will contain further files
4108providing the x509 certificates. The certificates must be stored
4109in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
4110@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
4111@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
4112
4113For the @var{server-key.pem} and @var{client-key.pem} files which
4114contain sensitive private keys, it is possible to use an encrypted
4115version by providing the @var{passwordid} parameter. This provides
4116the ID of a previously created @code{secret} object containing the
4117password for decryption.
4118
4119@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
4120
4121Interval @var{t} can't be 0, this filter batches the packet delivery: all
4122packets arriving in a given interval on netdev @var{netdevid} are delayed
4123until the end of the interval. Interval is in microseconds.
4124@option{status} is optional that indicate whether the netfilter is
4125on (enabled) or off (disabled), the default status for netfilter will be 'on'.
4126
4127queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4128
4129@option{all}: the filter is attached both to the receive and the transmit
4130              queue of the netdev (default).
4131
4132@option{rx}: the filter is attached to the receive queue of the netdev,
4133             where it will receive packets sent to the netdev.
4134
4135@option{tx}: the filter is attached to the transmit queue of the netdev,
4136             where it will receive packets sent by the netdev.
4137
4138@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4139
4140filter-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.
4141
4142@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4143
4144filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4145@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
4146filter-redirector will redirect packet with vnet_hdr_len.
4147Create a filter-redirector we need to differ outdev id from indev id, id can not
4148be the same. we can just use indev or outdev, but at least one of indev or outdev
4149need to be specified.
4150
4151@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4152
4153Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4154secondary from primary to keep secondary tcp connection,and rewrite
4155tcp packet to primary from secondary make tcp packet can be handled by
4156client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4157
4158usage:
4159colo secondary:
4160-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4161-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4162-object filter-rewriter,id=rew0,netdev=hn0,queue=all
4163
4164@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4165
4166Dump the network traffic on netdev @var{dev} to the file specified by
4167@var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4168The file format is libpcap, so it can be analyzed with tools such as tcpdump
4169or Wireshark.
4170
4171@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4172
4173Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4174secondary packet. If the packets are same, we will output primary
4175packet to outdev@var{chardevid}, else we will notify colo-frame
4176do checkpoint and send primary packet to outdev@var{chardevid}.
4177if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4178
4179we must use it with the help of filter-mirror and filter-redirector.
4180
4181@example
4182
4183primary:
4184-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4185-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4186-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4187-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4188-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4189-chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4190-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4191-chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4192-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4193-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4194-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4195-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4196
4197secondary:
4198-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4199-device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4200-chardev socket,id=red0,host=3.3.3.3,port=9003
4201-chardev socket,id=red1,host=3.3.3.3,port=9004
4202-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4203-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4204
4205@end example
4206
4207If you want to know the detail of above command line, you can read
4208the colo-compare git log.
4209
4210@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4211
4212Creates a cryptodev backend which executes crypto opreation from
4213the QEMU cipher APIS. The @var{id} parameter is
4214a unique ID that will be used to reference this cryptodev backend from
4215the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4216which specify the queue number of cryptodev backend, the default of
4217@var{queues} is 1.
4218
4219@example
4220
4221 # qemu-system-x86_64 \
4222   [...] \
4223       -object cryptodev-backend-builtin,id=cryptodev0 \
4224       -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4225   [...]
4226@end example
4227
4228@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4229@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4230
4231Defines a secret to store a password, encryption key, or some other sensitive
4232data. The sensitive data can either be passed directly via the @var{data}
4233parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4234parameter is insecure unless the sensitive data is encrypted.
4235
4236The sensitive data can be provided in raw format (the default), or base64.
4237When encoded as JSON, the raw format only supports valid UTF-8 characters,
4238so base64 is recommended for sending binary data. QEMU will convert from
4239which ever format is provided to the format it needs internally. eg, an
4240RBD password can be provided in raw format, even though it will be base64
4241encoded when passed onto the RBD sever.
4242
4243For added protection, it is possible to encrypt the data associated with
4244a secret using the AES-256-CBC cipher. Use of encryption is indicated
4245by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4246parameter provides the ID of a previously defined secret that contains
4247the AES-256 decryption key. This key should be 32-bytes long and be
4248base64 encoded. The @var{iv} parameter provides the random initialization
4249vector used for encryption of this particular secret and should be a
4250base64 encrypted string of the 16-byte IV.
4251
4252The simplest (insecure) usage is to provide the secret inline
4253
4254@example
4255
4256 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4257
4258@end example
4259
4260The simplest secure usage is to provide the secret via a file
4261
4262 # printf "letmein" > mypasswd.txt
4263 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4264
4265For greater security, AES-256-CBC should be used. To illustrate usage,
4266consider the openssl command line tool which can encrypt the data. Note
4267that when encrypting, the plaintext must be padded to the cipher block
4268size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4269
4270First a master key needs to be created in base64 encoding:
4271
4272@example
4273 # openssl rand -base64 32 > key.b64
4274 # KEY=$(base64 -d key.b64 | hexdump  -v -e '/1 "%02X"')
4275@end example
4276
4277Each secret to be encrypted needs to have a random initialization vector
4278generated. These do not need to be kept secret
4279
4280@example
4281 # openssl rand -base64 16 > iv.b64
4282 # IV=$(base64 -d iv.b64 | hexdump  -v -e '/1 "%02X"')
4283@end example
4284
4285The secret to be defined can now be encrypted, in this case we're
4286telling openssl to base64 encode the result, but it could be left
4287as raw bytes if desired.
4288
4289@example
4290 # SECRET=$(printf "letmein" |
4291            openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4292@end example
4293
4294When launching QEMU, create a master secret pointing to @code{key.b64}
4295and specify that to be used to decrypt the user password. Pass the
4296contents of @code{iv.b64} to the second secret
4297
4298@example
4299 # $QEMU \
4300     -object secret,id=secmaster0,format=base64,file=key.b64 \
4301     -object secret,id=sec0,keyid=secmaster0,format=base64,\
4302         data=$SECRET,iv=$(<iv.b64)
4303@end example
4304
4305@end table
4306
4307ETEXI
4308
4309
4310HXCOMM This is the last statement. Insert new options before this line!
4311STEXI
4312@end table
4313ETEXI
4314