xref: /openbmc/qemu/qemu-options.hx (revision ff8f06ee7680fb505079d33caaf8f5ebff0853bc)
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, tcg (default: tcg)\n"
35    "                kernel_irqchip=on|off controls accelerated irqchip support\n"
36    "                vmport=on|off|auto controls emulation of vmport (default: auto)\n"
37    "                kvm_shadow_mem=size of KVM shadow MMU\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    "                iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n"
41    "                igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
42    "                aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
43    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
44    "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n",
45    QEMU_ARCH_ALL)
46STEXI
47@item -machine [type=]@var{name}[,prop=@var{value}[,...]]
48@findex -machine
49Select the emulated machine by @var{name}. Use @code{-machine help} to list
50available machines. Supported machine properties are:
51@table @option
52@item accel=@var{accels1}[:@var{accels2}[:...]]
53This is used to enable an accelerator. Depending on the target architecture,
54kvm, xen, or tcg can be available. By default, tcg is used. If there is more
55than one accelerator specified, the next one is used if the previous one fails
56to initialize.
57@item kernel_irqchip=on|off
58Enables in-kernel irqchip support for the chosen accelerator when available.
59@item gfx_passthru=on|off
60Enables IGD GFX passthrough support for the chosen machine when available.
61@item vmport=on|off|auto
62Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the
63value based on accel. For accel=xen the default is off otherwise the default
64is on.
65@item kvm_shadow_mem=size
66Defines the size of the KVM shadow MMU.
67@item dump-guest-core=on|off
68Include guest memory in a core dump. The default is on.
69@item mem-merge=on|off
70Enables or disables memory merge support. This feature, when supported by
71the host, de-duplicates identical memory pages among VMs instances
72(enabled by default).
73@item iommu=on|off
74Enables or disables emulated Intel IOMMU (VT-d) support. The default is off.
75@item aes-key-wrap=on|off
76Enables or disables AES key wrapping support on s390-ccw hosts. This feature
77controls whether AES wrapping keys will be created to allow
78execution of AES cryptographic functions.  The default is on.
79@item dea-key-wrap=on|off
80Enables or disables DEA key wrapping support on s390-ccw hosts. This feature
81controls whether DEA wrapping keys will be created to allow
82execution of DEA cryptographic functions.  The default is on.
83@end table
84ETEXI
85
86HXCOMM Deprecated by -machine
87DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
88
89DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
90    "-cpu cpu        select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
91STEXI
92@item -cpu @var{model}
93@findex -cpu
94Select CPU model (@code{-cpu help} for list and additional feature selection)
95ETEXI
96
97DEF("smp", HAS_ARG, QEMU_OPTION_smp,
98    "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
99    "                set the number of CPUs to 'n' [default=1]\n"
100    "                maxcpus= maximum number of total cpus, including\n"
101    "                offline CPUs for hotplug, etc\n"
102    "                cores= number of CPU cores on one socket\n"
103    "                threads= number of threads on one CPU core\n"
104    "                sockets= number of discrete sockets in the system\n",
105        QEMU_ARCH_ALL)
106STEXI
107@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
108@findex -smp
109Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
110CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
111to 4.
112For the PC target, the number of @var{cores} per socket, the number
113of @var{threads} per cores and the total number of @var{sockets} can be
114specified. Missing values will be computed. If any on the three values is
115given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
116specifies the maximum number of hotpluggable CPUs.
117ETEXI
118
119DEF("numa", HAS_ARG, QEMU_OPTION_numa,
120    "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n"
121    "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
122STEXI
123@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
124@itemx -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
125@findex -numa
126Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev}
127and @samp{cpus} are omitted, resources are split equally. Also, note
128that the -@option{numa} option doesn't allocate any of the specified
129resources. That is, it just assigns existing resources to NUMA nodes. This
130means that one still has to use the @option{-m}, @option{-smp} options
131to allocate RAM and VCPUs respectively, and possibly @option{-object}
132to specify the memory backend for the @samp{memdev} suboption.
133
134@samp{mem} and @samp{memdev} are mutually exclusive.  Furthermore, if one
135node uses @samp{memdev}, all of them have to use it.
136ETEXI
137
138DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
139    "-add-fd fd=fd,set=set[,opaque=opaque]\n"
140    "                Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
141STEXI
142@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
143@findex -add-fd
144
145Add a file descriptor to an fd set.  Valid options are:
146
147@table @option
148@item fd=@var{fd}
149This option defines the file descriptor of which a duplicate is added to fd set.
150The file descriptor cannot be stdin, stdout, or stderr.
151@item set=@var{set}
152This option defines the ID of the fd set to add the file descriptor to.
153@item opaque=@var{opaque}
154This option defines a free-form string that can be used to describe @var{fd}.
155@end table
156
157You can open an image using pre-opened file descriptors from an fd set:
158@example
159qemu-system-i386
160-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
161-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
162-drive file=/dev/fdset/2,index=0,media=disk
163@end example
164ETEXI
165
166DEF("set", HAS_ARG, QEMU_OPTION_set,
167    "-set group.id.arg=value\n"
168    "                set <arg> parameter for item <id> of type <group>\n"
169    "                i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
170STEXI
171@item -set @var{group}.@var{id}.@var{arg}=@var{value}
172@findex -set
173Set parameter @var{arg} for item @var{id} of type @var{group}\n"
174ETEXI
175
176DEF("global", HAS_ARG, QEMU_OPTION_global,
177    "-global driver.property=value\n"
178    "-global driver=driver,property=property,value=value\n"
179    "                set a global default for a driver property\n",
180    QEMU_ARCH_ALL)
181STEXI
182@item -global @var{driver}.@var{prop}=@var{value}
183@itemx -global driver=@var{driver},property=@var{property},value=@var{value}
184@findex -global
185Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
186
187@example
188qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
189@end example
190
191In particular, you can use this to set driver properties for devices which are
192created automatically by the machine model. To create a device which is not
193created automatically and set properties on it, use -@option{device}.
194
195-global @var{driver}.@var{prop}=@var{value} is shorthand for -global
196driver=@var{driver},property=@var{prop},value=@var{value}.  The
197longhand syntax works even when @var{driver} contains a dot.
198ETEXI
199
200DEF("boot", HAS_ARG, QEMU_OPTION_boot,
201    "-boot [order=drives][,once=drives][,menu=on|off]\n"
202    "      [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
203    "                'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
204    "                'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
205    "                'sp_time': the period that splash picture last if menu=on, unit is ms\n"
206    "                'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
207    QEMU_ARCH_ALL)
208STEXI
209@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]
210@findex -boot
211Specify boot order @var{drives} as a string of drive letters. Valid
212drive letters depend on the target architecture. The x86 PC uses: a, b
213(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
214from network adapter 1-4), hard disk boot is the default. To apply a
215particular boot order only on the first startup, specify it via
216@option{once}.
217
218Interactive boot menus/prompts can be enabled via @option{menu=on} as far
219as firmware/BIOS supports them. The default is non-interactive boot.
220
221A splash picture could be passed to bios, enabling user to show it as logo,
222when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
223supports them. Currently Seabios for X86 system support it.
224limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
225format(true color). The resolution should be supported by the SVGA mode, so
226the recommended is 320x240, 640x480, 800x640.
227
228A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
229when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
230reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
231system support it.
232
233Do strict boot via @option{strict=on} as far as firmware/BIOS
234supports it. This only effects when boot priority is changed by
235bootindex options. The default is non-strict boot.
236
237@example
238# try to boot from network first, then from hard disk
239qemu-system-i386 -boot order=nc
240# boot from CD-ROM first, switch back to default order after reboot
241qemu-system-i386 -boot once=d
242# boot with a splash picture for 5 seconds.
243qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
244@end example
245
246Note: The legacy format '-boot @var{drives}' is still supported but its
247use is discouraged as it may be removed from future versions.
248ETEXI
249
250DEF("m", HAS_ARG, QEMU_OPTION_m,
251    "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
252    "                configure guest RAM\n"
253    "                size: initial amount of guest memory\n"
254    "                slots: number of hotplug slots (default: none)\n"
255    "                maxmem: maximum amount of guest memory (default: none)\n"
256    "NOTE: Some architectures might enforce a specific granularity\n",
257    QEMU_ARCH_ALL)
258STEXI
259@item -m [size=]@var{megs}[,slots=n,maxmem=size]
260@findex -m
261Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
262Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
263megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
264could be used to set amount of hotpluggable memory slots and maximum amount of
265memory. Note that @var{maxmem} must be aligned to the page size.
266
267For example, the following command-line sets the guest startup RAM size to
2681GB, creates 3 slots to hotplug additional memory and sets the maximum
269memory the guest can reach to 4GB:
270
271@example
272qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
273@end example
274
275If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
276be enabled and the guest startup RAM will never increase.
277ETEXI
278
279DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
280    "-mem-path FILE  provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
281STEXI
282@item -mem-path @var{path}
283@findex -mem-path
284Allocate guest RAM from a temporarily created file in @var{path}.
285ETEXI
286
287DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
288    "-mem-prealloc   preallocate guest memory (use with -mem-path)\n",
289    QEMU_ARCH_ALL)
290STEXI
291@item -mem-prealloc
292@findex -mem-prealloc
293Preallocate memory when using -mem-path.
294ETEXI
295
296DEF("k", HAS_ARG, QEMU_OPTION_k,
297    "-k language     use keyboard layout (for example 'fr' for French)\n",
298    QEMU_ARCH_ALL)
299STEXI
300@item -k @var{language}
301@findex -k
302Use keyboard layout @var{language} (for example @code{fr} for
303French). This option is only needed where it is not easy to get raw PC
304keycodes (e.g. on Macs, with some X11 servers or with a VNC
305display). You don't normally need to use it on PC/Linux or PC/Windows
306hosts.
307
308The available layouts are:
309@example
310ar  de-ch  es  fo     fr-ca  hu  ja  mk     no  pt-br  sv
311da  en-gb  et  fr     fr-ch  is  lt  nl     pl  ru     th
312de  en-us  fi  fr-be  hr     it  lv  nl-be  pt  sl     tr
313@end example
314
315The default is @code{en-us}.
316ETEXI
317
318
319DEF("audio-help", 0, QEMU_OPTION_audio_help,
320    "-audio-help     print list of audio drivers and their options\n",
321    QEMU_ARCH_ALL)
322STEXI
323@item -audio-help
324@findex -audio-help
325Will show the audio subsystem help: list of drivers, tunable
326parameters.
327ETEXI
328
329DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
330    "-soundhw c1,... enable audio support\n"
331    "                and only specified sound cards (comma separated list)\n"
332    "                use '-soundhw help' to get the list of supported cards\n"
333    "                use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
334STEXI
335@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
336@findex -soundhw
337Enable audio and selected sound hardware. Use 'help' to print all
338available sound hardware.
339
340@example
341qemu-system-i386 -soundhw sb16,adlib disk.img
342qemu-system-i386 -soundhw es1370 disk.img
343qemu-system-i386 -soundhw ac97 disk.img
344qemu-system-i386 -soundhw hda disk.img
345qemu-system-i386 -soundhw all disk.img
346qemu-system-i386 -soundhw help
347@end example
348
349Note that Linux's i810_audio OSS kernel (for AC97) module might
350require manually specifying clocking.
351
352@example
353modprobe i810_audio clocking=48000
354@end example
355ETEXI
356
357DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
358    "-balloon none   disable balloon device\n"
359    "-balloon virtio[,addr=str]\n"
360    "                enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
361STEXI
362@item -balloon none
363@findex -balloon
364Disable balloon device.
365@item -balloon virtio[,addr=@var{addr}]
366Enable virtio balloon device (default), optionally with PCI address
367@var{addr}.
368ETEXI
369
370DEF("device", HAS_ARG, QEMU_OPTION_device,
371    "-device driver[,prop[=value][,...]]\n"
372    "                add device (based on driver)\n"
373    "                prop=value,... sets driver properties\n"
374    "                use '-device help' to print all possible drivers\n"
375    "                use '-device driver,help' to print all possible properties\n",
376    QEMU_ARCH_ALL)
377STEXI
378@item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
379@findex -device
380Add device @var{driver}.  @var{prop}=@var{value} sets driver
381properties.  Valid properties depend on the driver.  To get help on
382possible drivers and properties, use @code{-device help} and
383@code{-device @var{driver},help}.
384ETEXI
385
386DEF("name", HAS_ARG, QEMU_OPTION_name,
387    "-name string1[,process=string2][,debug-threads=on|off]\n"
388    "                set the name of the guest\n"
389    "                string1 sets the window title and string2 the process name (on Linux)\n"
390    "                When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
391    "                NOTE: The thread names are for debugging and not a stable API.\n",
392    QEMU_ARCH_ALL)
393STEXI
394@item -name @var{name}
395@findex -name
396Sets the @var{name} of the guest.
397This name will be displayed in the SDL window caption.
398The @var{name} will also be used for the VNC server.
399Also optionally set the top visible process name in Linux.
400Naming of individual threads can also be enabled on Linux to aid debugging.
401ETEXI
402
403DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
404    "-uuid %08x-%04x-%04x-%04x-%012x\n"
405    "                specify machine UUID\n", QEMU_ARCH_ALL)
406STEXI
407@item -uuid @var{uuid}
408@findex -uuid
409Set system UUID.
410ETEXI
411
412STEXI
413@end table
414ETEXI
415DEFHEADING()
416
417DEFHEADING(Block device options:)
418STEXI
419@table @option
420ETEXI
421
422DEF("fda", HAS_ARG, QEMU_OPTION_fda,
423    "-fda/-fdb file  use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
424DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
425STEXI
426@item -fda @var{file}
427@itemx -fdb @var{file}
428@findex -fda
429@findex -fdb
430Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
431ETEXI
432
433DEF("hda", HAS_ARG, QEMU_OPTION_hda,
434    "-hda/-hdb file  use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
435DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
436DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
437    "-hdc/-hdd file  use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
438DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
439STEXI
440@item -hda @var{file}
441@itemx -hdb @var{file}
442@itemx -hdc @var{file}
443@itemx -hdd @var{file}
444@findex -hda
445@findex -hdb
446@findex -hdc
447@findex -hdd
448Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
449ETEXI
450
451DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
452    "-cdrom file     use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
453    QEMU_ARCH_ALL)
454STEXI
455@item -cdrom @var{file}
456@findex -cdrom
457Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
458@option{-cdrom} at the same time). You can use the host CD-ROM by
459using @file{/dev/cdrom} as filename (@pxref{host_drives}).
460ETEXI
461
462DEF("drive", HAS_ARG, QEMU_OPTION_drive,
463    "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
464    "       [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
465    "       [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
466    "       [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
467    "       [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
468    "       [,readonly=on|off][,copy-on-read=on|off]\n"
469    "       [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
470    "       [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
471    "       [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
472    "       [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
473    "       [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
474    "       [[,iops_size=is]]\n"
475    "       [[,group=g]]\n"
476    "                use 'file' as a drive image\n", QEMU_ARCH_ALL)
477STEXI
478@item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
479@findex -drive
480
481Define a new drive. Valid options are:
482
483@table @option
484@item file=@var{file}
485This option defines which disk image (@pxref{disk_images}) to use with
486this drive. If the filename contains comma, you must double it
487(for instance, "file=my,,file" to use file "my,file").
488
489Special files such as iSCSI devices can be specified using protocol
490specific URLs. See the section for "Device URL Syntax" for more information.
491@item if=@var{interface}
492This option defines on which type on interface the drive is connected.
493Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
494@item bus=@var{bus},unit=@var{unit}
495These options define where is connected the drive by defining the bus number and
496the unit id.
497@item index=@var{index}
498This option defines where is connected the drive by using an index in the list
499of available connectors of a given interface type.
500@item media=@var{media}
501This option defines the type of the media: disk or cdrom.
502@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
503These options have the same definition as they have in @option{-hdachs}.
504@item snapshot=@var{snapshot}
505@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
506(see @option{-snapshot}).
507@item cache=@var{cache}
508@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
509@item aio=@var{aio}
510@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
511@item discard=@var{discard}
512@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem.  Some machine types may not support discard requests.
513@item format=@var{format}
514Specify which disk @var{format} will be used rather than detecting
515the format.  Can be used to specifiy format=raw to avoid interpreting
516an untrusted format header.
517@item serial=@var{serial}
518This option specifies the serial number to assign to the device.
519@item addr=@var{addr}
520Specify the controller's PCI address (if=virtio only).
521@item werror=@var{action},rerror=@var{action}
522Specify which @var{action} to take on write and read errors. Valid actions are:
523"ignore" (ignore the error and try to continue), "stop" (pause QEMU),
524"report" (report the error to the guest), "enospc" (pause QEMU only if the
525host disk is full; report the error to the guest otherwise).
526The default setting is @option{werror=enospc} and @option{rerror=report}.
527@item readonly
528Open drive @option{file} as read-only. Guest write attempts will fail.
529@item copy-on-read=@var{copy-on-read}
530@var{copy-on-read} is "on" or "off" and enables whether to copy read backing
531file sectors into the image file.
532@item detect-zeroes=@var{detect-zeroes}
533@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
534conversion of plain zero writes by the OS to driver specific optimized
535zero write commands. You may even choose "unmap" if @var{discard} is set
536to "unmap" to allow a zero write to be converted to an UNMAP operation.
537@end table
538
539By default, the @option{cache=writeback} mode is used. It will report data
540writes as completed as soon as the data is present in the host page cache.
541This is safe as long as your guest OS makes sure to correctly flush disk caches
542where needed. If your guest OS does not handle volatile disk write caches
543correctly and your host crashes or loses power, then the guest may experience
544data corruption.
545
546For such guests, you should consider using @option{cache=writethrough}. This
547means that the host page cache will be used to read and write data, but write
548notification will be sent to the guest only after QEMU has made sure to flush
549each write to the disk. Be aware that this has a major impact on performance.
550
551The host page cache can be avoided entirely with @option{cache=none}.  This will
552attempt to do disk IO directly to the guest's memory.  QEMU may still perform
553an internal copy of the data. Note that this is considered a writeback mode and
554the guest OS must handle the disk write cache correctly in order to avoid data
555corruption on host crashes.
556
557The host page cache can be avoided while only sending write notifications to
558the guest when the data has been flushed to the disk using
559@option{cache=directsync}.
560
561In case you don't care about data integrity over host failures, use
562@option{cache=unsafe}. This option tells QEMU that it never needs to write any
563data to the disk but can instead keep things in cache. If anything goes wrong,
564like your host losing power, the disk storage getting disconnected accidentally,
565etc. your image will most probably be rendered unusable.   When using
566the @option{-snapshot} option, unsafe caching is always used.
567
568Copy-on-read avoids accessing the same backing file sectors repeatedly and is
569useful when the backing file is over a slow network.  By default copy-on-read
570is off.
571
572Instead of @option{-cdrom} you can use:
573@example
574qemu-system-i386 -drive file=file,index=2,media=cdrom
575@end example
576
577Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
578use:
579@example
580qemu-system-i386 -drive file=file,index=0,media=disk
581qemu-system-i386 -drive file=file,index=1,media=disk
582qemu-system-i386 -drive file=file,index=2,media=disk
583qemu-system-i386 -drive file=file,index=3,media=disk
584@end example
585
586You can open an image using pre-opened file descriptors from an fd set:
587@example
588qemu-system-i386
589-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
590-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
591-drive file=/dev/fdset/2,index=0,media=disk
592@end example
593
594You can connect a CDROM to the slave of ide0:
595@example
596qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
597@end example
598
599If you don't specify the "file=" argument, you define an empty drive:
600@example
601qemu-system-i386 -drive if=ide,index=1,media=cdrom
602@end example
603
604You can connect a SCSI disk with unit ID 6 on the bus #0:
605@example
606qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
607@end example
608
609Instead of @option{-fda}, @option{-fdb}, you can use:
610@example
611qemu-system-i386 -drive file=file,index=0,if=floppy
612qemu-system-i386 -drive file=file,index=1,if=floppy
613@end example
614
615By default, @var{interface} is "ide" and @var{index} is automatically
616incremented:
617@example
618qemu-system-i386 -drive file=a -drive file=b"
619@end example
620is interpreted like:
621@example
622qemu-system-i386 -hda a -hdb b
623@end example
624ETEXI
625
626DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
627    "-mtdblock file  use 'file' as on-board Flash memory image\n",
628    QEMU_ARCH_ALL)
629STEXI
630@item -mtdblock @var{file}
631@findex -mtdblock
632Use @var{file} as on-board Flash memory image.
633ETEXI
634
635DEF("sd", HAS_ARG, QEMU_OPTION_sd,
636    "-sd file        use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
637STEXI
638@item -sd @var{file}
639@findex -sd
640Use @var{file} as SecureDigital card image.
641ETEXI
642
643DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
644    "-pflash file    use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
645STEXI
646@item -pflash @var{file}
647@findex -pflash
648Use @var{file} as a parallel flash image.
649ETEXI
650
651DEF("snapshot", 0, QEMU_OPTION_snapshot,
652    "-snapshot       write to temporary files instead of disk image files\n",
653    QEMU_ARCH_ALL)
654STEXI
655@item -snapshot
656@findex -snapshot
657Write to temporary files instead of disk image files. In this case,
658the raw disk image you use is not written back. You can however force
659the write back by pressing @key{C-a s} (@pxref{disk_images}).
660ETEXI
661
662DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
663    "-hdachs c,h,s[,t]\n" \
664    "                force hard disk 0 physical geometry and the optional BIOS\n" \
665    "                translation (t=none or lba) (usually QEMU can guess them)\n",
666    QEMU_ARCH_ALL)
667STEXI
668@item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
669@findex -hdachs
670Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
671@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
672translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
673all those parameters. This option is useful for old MS-DOS disk
674images.
675ETEXI
676
677DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
678    "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
679    " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
680    QEMU_ARCH_ALL)
681
682STEXI
683
684@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}]
685@findex -fsdev
686Define a new file system device. Valid options are:
687@table @option
688@item @var{fsdriver}
689This option specifies the fs driver backend to use.
690Currently "local", "handle" and "proxy" file system drivers are supported.
691@item id=@var{id}
692Specifies identifier for this device
693@item path=@var{path}
694Specifies the export path for the file system device. Files under
695this path will be available to the 9p client on the guest.
696@item security_model=@var{security_model}
697Specifies the security model to be used for this export path.
698Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
699In "passthrough" security model, files are stored using the same
700credentials as they are created on the guest. This requires QEMU
701to run as root. In "mapped-xattr" security model, some of the file
702attributes like uid, gid, mode bits and link target are stored as
703file attributes. For "mapped-file" these attributes are stored in the
704hidden .virtfs_metadata directory. Directories exported by this security model cannot
705interact with other unix tools. "none" security model is same as
706passthrough except the sever won't report failures if it fails to
707set file attributes like ownership. Security model is mandatory
708only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
709security model as a parameter.
710@item writeout=@var{writeout}
711This is an optional argument. The only supported value is "immediate".
712This means that host page cache will be used to read and write data but
713write notification will be sent to the guest only when the data has been
714reported as written by the storage subsystem.
715@item readonly
716Enables exporting 9p share as a readonly mount for guests. By default
717read-write access is given.
718@item socket=@var{socket}
719Enables proxy filesystem driver to use passed socket file for communicating
720with virtfs-proxy-helper
721@item sock_fd=@var{sock_fd}
722Enables proxy filesystem driver to use passed socket descriptor for
723communicating with virtfs-proxy-helper. Usually a helper like libvirt
724will create socketpair and pass one of the fds as sock_fd
725@end table
726
727-fsdev option is used along with -device driver "virtio-9p-pci".
728@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
729Options for virtio-9p-pci driver are:
730@table @option
731@item fsdev=@var{id}
732Specifies the id value specified along with -fsdev option
733@item mount_tag=@var{mount_tag}
734Specifies the tag name to be used by the guest to mount this export point
735@end table
736
737ETEXI
738
739DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
740    "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
741    "        [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
742    QEMU_ARCH_ALL)
743
744STEXI
745
746@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}]
747@findex -virtfs
748
749The general form of a Virtual File system pass-through options are:
750@table @option
751@item @var{fsdriver}
752This option specifies the fs driver backend to use.
753Currently "local", "handle" and "proxy" file system drivers are supported.
754@item id=@var{id}
755Specifies identifier for this device
756@item path=@var{path}
757Specifies the export path for the file system device. Files under
758this path will be available to the 9p client on the guest.
759@item security_model=@var{security_model}
760Specifies the security model to be used for this export path.
761Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
762In "passthrough" security model, files are stored using the same
763credentials as they are created on the guest. This requires QEMU
764to run as root. In "mapped-xattr" security model, some of the file
765attributes like uid, gid, mode bits and link target are stored as
766file attributes. For "mapped-file" these attributes are stored in the
767hidden .virtfs_metadata directory. Directories exported by this security model cannot
768interact with other unix tools. "none" security model is same as
769passthrough except the sever won't report failures if it fails to
770set file attributes like ownership. Security model is mandatory only
771for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
772model as a parameter.
773@item writeout=@var{writeout}
774This is an optional argument. The only supported value is "immediate".
775This means that host page cache will be used to read and write data but
776write notification will be sent to the guest only when the data has been
777reported as written by the storage subsystem.
778@item readonly
779Enables exporting 9p share as a readonly mount for guests. By default
780read-write access is given.
781@item socket=@var{socket}
782Enables proxy filesystem driver to use passed socket file for
783communicating with virtfs-proxy-helper. Usually a helper like libvirt
784will create socketpair and pass one of the fds as sock_fd
785@item sock_fd
786Enables proxy filesystem driver to use passed 'sock_fd' as the socket
787descriptor for interfacing with virtfs-proxy-helper
788@end table
789ETEXI
790
791DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
792    "-virtfs_synth Create synthetic file system image\n",
793    QEMU_ARCH_ALL)
794STEXI
795@item -virtfs_synth
796@findex -virtfs_synth
797Create synthetic file system image
798ETEXI
799
800STEXI
801@end table
802ETEXI
803DEFHEADING()
804
805DEFHEADING(USB options:)
806STEXI
807@table @option
808ETEXI
809
810DEF("usb", 0, QEMU_OPTION_usb,
811    "-usb            enable the USB driver (will be the default soon)\n",
812    QEMU_ARCH_ALL)
813STEXI
814@item -usb
815@findex -usb
816Enable the USB driver (will be the default soon)
817ETEXI
818
819DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
820    "-usbdevice name add the host or guest USB device 'name'\n",
821    QEMU_ARCH_ALL)
822STEXI
823
824@item -usbdevice @var{devname}
825@findex -usbdevice
826Add the USB device @var{devname}. @xref{usb_devices}.
827
828@table @option
829
830@item mouse
831Virtual Mouse. This will override the PS/2 mouse emulation when activated.
832
833@item tablet
834Pointer device that uses absolute coordinates (like a touchscreen). This
835means QEMU is able to report the mouse position without having to grab the
836mouse. Also overrides the PS/2 mouse emulation when activated.
837
838@item disk:[format=@var{format}]:@var{file}
839Mass storage device based on file. The optional @var{format} argument
840will be used rather than detecting the format. Can be used to specifiy
841@code{format=raw} to avoid interpreting an untrusted format header.
842
843@item host:@var{bus}.@var{addr}
844Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
845
846@item host:@var{vendor_id}:@var{product_id}
847Pass through the host device identified by @var{vendor_id}:@var{product_id}
848(Linux only).
849
850@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
851Serial converter to host character device @var{dev}, see @code{-serial} for the
852available devices.
853
854@item braille
855Braille device.  This will use BrlAPI to display the braille output on a real
856or fake device.
857
858@item net:@var{options}
859Network adapter that supports CDC ethernet and RNDIS protocols.
860
861@end table
862ETEXI
863
864STEXI
865@end table
866ETEXI
867DEFHEADING()
868
869DEFHEADING(Display options:)
870STEXI
871@table @option
872ETEXI
873
874DEF("display", HAS_ARG, QEMU_OPTION_display,
875    "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
876    "            [,window_close=on|off]|curses|none|\n"
877    "            gtk[,grab_on_hover=on|off]|\n"
878    "            vnc=<display>[,<optargs>]\n"
879    "                select display type\n", QEMU_ARCH_ALL)
880STEXI
881@item -display @var{type}
882@findex -display
883Select type of display to use. This option is a replacement for the
884old style -sdl/-curses/... options. Valid values for @var{type} are
885@table @option
886@item sdl
887Display video output via SDL (usually in a separate graphics
888window; see the SDL documentation for other possibilities).
889@item curses
890Display video output via curses. For graphics device models which
891support a text mode, QEMU can display this output using a
892curses/ncurses interface. Nothing is displayed when the graphics
893device is in graphical mode or if the graphics device does not support
894a text mode. Generally only the VGA device models support text mode.
895@item none
896Do not display video output. The guest will still see an emulated
897graphics card, but its output will not be displayed to the QEMU
898user. This option differs from the -nographic option in that it
899only affects what is done with video output; -nographic also changes
900the destination of the serial and parallel port data.
901@item gtk
902Display video output in a GTK window. This interface provides drop-down
903menus and other UI elements to configure and control the VM during
904runtime.
905@item vnc
906Start a VNC server on display <arg>
907@end table
908ETEXI
909
910DEF("nographic", 0, QEMU_OPTION_nographic,
911    "-nographic      disable graphical output and redirect serial I/Os to console\n",
912    QEMU_ARCH_ALL)
913STEXI
914@item -nographic
915@findex -nographic
916Normally, QEMU uses SDL to display the VGA output. With this option,
917you can totally disable graphical output so that QEMU is a simple
918command line application. The emulated serial port is redirected on
919the console and muxed with the monitor (unless redirected elsewhere
920explicitly). Therefore, you can still use QEMU to debug a Linux kernel
921with a serial console.  Use @key{C-a h} for help on switching between
922the console and monitor.
923ETEXI
924
925DEF("curses", 0, QEMU_OPTION_curses,
926    "-curses         use a curses/ncurses interface instead of SDL\n",
927    QEMU_ARCH_ALL)
928STEXI
929@item -curses
930@findex -curses
931Normally, QEMU uses SDL to display the VGA output.  With this option,
932QEMU can display the VGA output when in text mode using a
933curses/ncurses interface.  Nothing is displayed in graphical mode.
934ETEXI
935
936DEF("no-frame", 0, QEMU_OPTION_no_frame,
937    "-no-frame       open SDL window without a frame and window decorations\n",
938    QEMU_ARCH_ALL)
939STEXI
940@item -no-frame
941@findex -no-frame
942Do not use decorations for SDL windows and start them using the whole
943available screen space. This makes the using QEMU in a dedicated desktop
944workspace more convenient.
945ETEXI
946
947DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
948    "-alt-grab       use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
949    QEMU_ARCH_ALL)
950STEXI
951@item -alt-grab
952@findex -alt-grab
953Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
954affects the special keys (for fullscreen, monitor-mode switching, etc).
955ETEXI
956
957DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
958    "-ctrl-grab      use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
959    QEMU_ARCH_ALL)
960STEXI
961@item -ctrl-grab
962@findex -ctrl-grab
963Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
964affects the special keys (for fullscreen, monitor-mode switching, etc).
965ETEXI
966
967DEF("no-quit", 0, QEMU_OPTION_no_quit,
968    "-no-quit        disable SDL window close capability\n", QEMU_ARCH_ALL)
969STEXI
970@item -no-quit
971@findex -no-quit
972Disable SDL window close capability.
973ETEXI
974
975DEF("sdl", 0, QEMU_OPTION_sdl,
976    "-sdl            enable SDL\n", QEMU_ARCH_ALL)
977STEXI
978@item -sdl
979@findex -sdl
980Enable SDL.
981ETEXI
982
983DEF("spice", HAS_ARG, QEMU_OPTION_spice,
984    "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
985    "       [,x509-key-file=<file>][,x509-key-password=<file>]\n"
986    "       [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
987    "       [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
988    "       [,tls-ciphers=<list>]\n"
989    "       [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
990    "       [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
991    "       [,sasl][,password=<secret>][,disable-ticketing]\n"
992    "       [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
993    "       [,jpeg-wan-compression=[auto|never|always]]\n"
994    "       [,zlib-glz-wan-compression=[auto|never|always]]\n"
995    "       [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
996    "       [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
997    "       [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
998    "   enable spice\n"
999    "   at least one of {port, tls-port} is mandatory\n",
1000    QEMU_ARCH_ALL)
1001STEXI
1002@item -spice @var{option}[,@var{option}[,...]]
1003@findex -spice
1004Enable the spice remote desktop protocol. Valid options are
1005
1006@table @option
1007
1008@item port=<nr>
1009Set the TCP port spice is listening on for plaintext channels.
1010
1011@item addr=<addr>
1012Set the IP address spice is listening on.  Default is any address.
1013
1014@item ipv4
1015@itemx ipv6
1016@itemx unix
1017Force using the specified IP version.
1018
1019@item password=<secret>
1020Set the password you need to authenticate.
1021
1022@item sasl
1023Require that the client use SASL to authenticate with the spice.
1024The exact choice of authentication method used is controlled from the
1025system / user's SASL configuration file for the 'qemu' service. This
1026is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1027unprivileged user, an environment variable SASL_CONF_PATH can be used
1028to make it search alternate locations for the service config.
1029While some SASL auth methods can also provide data encryption (eg GSSAPI),
1030it is recommended that SASL always be combined with the 'tls' and
1031'x509' settings to enable use of SSL and server certificates. This
1032ensures a data encryption preventing compromise of authentication
1033credentials.
1034
1035@item disable-ticketing
1036Allow client connects without authentication.
1037
1038@item disable-copy-paste
1039Disable copy paste between the client and the guest.
1040
1041@item disable-agent-file-xfer
1042Disable spice-vdagent based file-xfer between the client and the guest.
1043
1044@item tls-port=<nr>
1045Set the TCP port spice is listening on for encrypted channels.
1046
1047@item x509-dir=<dir>
1048Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1049
1050@item x509-key-file=<file>
1051@itemx x509-key-password=<file>
1052@itemx x509-cert-file=<file>
1053@itemx x509-cacert-file=<file>
1054@itemx x509-dh-key-file=<file>
1055The x509 file names can also be configured individually.
1056
1057@item tls-ciphers=<list>
1058Specify which ciphers to use.
1059
1060@item tls-channel=[main|display|cursor|inputs|record|playback]
1061@itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1062Force specific channel to be used with or without TLS encryption.  The
1063options can be specified multiple times to configure multiple
1064channels.  The special name "default" can be used to set the default
1065mode.  For channels which are not explicitly forced into one mode the
1066spice client is allowed to pick tls/plaintext as he pleases.
1067
1068@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1069Configure image compression (lossless).
1070Default is auto_glz.
1071
1072@item jpeg-wan-compression=[auto|never|always]
1073@itemx zlib-glz-wan-compression=[auto|never|always]
1074Configure wan image compression (lossy for slow links).
1075Default is auto.
1076
1077@item streaming-video=[off|all|filter]
1078Configure video stream detection.  Default is filter.
1079
1080@item agent-mouse=[on|off]
1081Enable/disable passing mouse events via vdagent.  Default is on.
1082
1083@item playback-compression=[on|off]
1084Enable/disable audio stream compression (using celt 0.5.1).  Default is on.
1085
1086@item seamless-migration=[on|off]
1087Enable/disable spice seamless migration. Default is off.
1088
1089@end table
1090ETEXI
1091
1092DEF("portrait", 0, QEMU_OPTION_portrait,
1093    "-portrait       rotate graphical output 90 deg left (only PXA LCD)\n",
1094    QEMU_ARCH_ALL)
1095STEXI
1096@item -portrait
1097@findex -portrait
1098Rotate graphical output 90 deg left (only PXA LCD).
1099ETEXI
1100
1101DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1102    "-rotate <deg>   rotate graphical output some deg left (only PXA LCD)\n",
1103    QEMU_ARCH_ALL)
1104STEXI
1105@item -rotate @var{deg}
1106@findex -rotate
1107Rotate graphical output some deg left (only PXA LCD).
1108ETEXI
1109
1110DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1111    "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1112    "                select video card type\n", QEMU_ARCH_ALL)
1113STEXI
1114@item -vga @var{type}
1115@findex -vga
1116Select type of VGA card to emulate. Valid values for @var{type} are
1117@table @option
1118@item cirrus
1119Cirrus Logic GD5446 Video card. All Windows versions starting from
1120Windows 95 should recognize and use this graphic card. For optimal
1121performances, use 16 bit color depth in the guest and the host OS.
1122(This one is the default)
1123@item std
1124Standard VGA card with Bochs VBE extensions.  If your guest OS
1125supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1126to use high resolution modes (>= 1280x1024x16) then you should use
1127this option.
1128@item vmware
1129VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1130recent XFree86/XOrg server or Windows guest with a driver for this
1131card.
1132@item qxl
1133QXL paravirtual graphic card.  It is VGA compatible (including VESA
11342.0 VBE support).  Works best with qxl guest drivers installed though.
1135Recommended choice when using the spice protocol.
1136@item tcx
1137(sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1138sun4m machines and offers both 8-bit and 24-bit colour depths at a
1139fixed resolution of 1024x768.
1140@item cg3
1141(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1142for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1143resolutions aimed at people wishing to run older Solaris versions.
1144@item virtio
1145Virtio VGA card.
1146@item none
1147Disable VGA card.
1148@end table
1149ETEXI
1150
1151DEF("full-screen", 0, QEMU_OPTION_full_screen,
1152    "-full-screen    start in full screen\n", QEMU_ARCH_ALL)
1153STEXI
1154@item -full-screen
1155@findex -full-screen
1156Start in full screen.
1157ETEXI
1158
1159DEF("g", 1, QEMU_OPTION_g ,
1160    "-g WxH[xDEPTH]  Set the initial graphical resolution and depth\n",
1161    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1162STEXI
1163@item -g @var{width}x@var{height}[x@var{depth}]
1164@findex -g
1165Set the initial graphical resolution and depth (PPC, SPARC only).
1166ETEXI
1167
1168DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1169    "-vnc display    start a VNC server on display\n", QEMU_ARCH_ALL)
1170STEXI
1171@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1172@findex -vnc
1173Normally, QEMU uses SDL to display the VGA output.  With this option,
1174you can have QEMU listen on VNC display @var{display} and redirect the VGA
1175display over the VNC session.  It is very useful to enable the usb
1176tablet device when using this option (option @option{-usbdevice
1177tablet}). When using the VNC display, you must use the @option{-k}
1178parameter to set the keyboard layout if you are not using en-us. Valid
1179syntax for the @var{display} is
1180
1181@table @option
1182
1183@item @var{host}:@var{d}
1184
1185TCP connections will only be allowed from @var{host} on display @var{d}.
1186By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1187be omitted in which case the server will accept connections from any host.
1188
1189@item unix:@var{path}
1190
1191Connections will be allowed over UNIX domain sockets where @var{path} is the
1192location of a unix socket to listen for connections on.
1193
1194@item none
1195
1196VNC is initialized but not started. The monitor @code{change} command
1197can be used to later start the VNC server.
1198
1199@end table
1200
1201Following the @var{display} value there may be one or more @var{option} flags
1202separated by commas. Valid options are
1203
1204@table @option
1205
1206@item reverse
1207
1208Connect to a listening VNC client via a ``reverse'' connection. The
1209client is specified by the @var{display}. For reverse network
1210connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1211is a TCP port number, not a display number.
1212
1213@item websocket
1214
1215Opens an additional TCP listening port dedicated to VNC Websocket connections.
1216By definition the Websocket port is 5700+@var{display}. If @var{host} is
1217specified connections will only be allowed from this host.
1218As an alternative the Websocket port could be specified by using
1219@code{websocket}=@var{port}.
1220If no TLS credentials are provided, the websocket connection runs in
1221unencrypted mode. If TLS credentials are provided, the websocket connection
1222requires encrypted client connections.
1223
1224@item password
1225
1226Require that password based authentication is used for client connections.
1227
1228The password must be set separately using the @code{set_password} command in
1229the @ref{pcsys_monitor}. The syntax to change your password is:
1230@code{set_password <protocol> <password>} where <protocol> could be either
1231"vnc" or "spice".
1232
1233If you would like to change <protocol> password expiration, you should use
1234@code{expire_password <protocol> <expiration-time>} where expiration time could
1235be one of the following options: now, never, +seconds or UNIX time of
1236expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1237to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1238date and time).
1239
1240You can also use keywords "now" or "never" for the expiration time to
1241allow <protocol> password to expire immediately or never expire.
1242
1243@item tls-creds=@var{ID}
1244
1245Provides the ID of a set of TLS credentials to use to secure the
1246VNC server. They will apply to both the normal VNC server socket
1247and the websocket socket (if enabled). Setting TLS credentials
1248will cause the VNC server socket to enable the VeNCrypt auth
1249mechanism.  The credentials should have been previously created
1250using the @option{-object tls-creds} argument.
1251
1252The @option{tls-creds} parameter obsoletes the @option{tls},
1253@option{x509}, and @option{x509verify} options, and as such
1254it is not permitted to set both new and old type options at
1255the same time.
1256
1257@item tls
1258
1259Require that client use TLS when communicating with the VNC server. This
1260uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1261attack. It is recommended that this option be combined with either the
1262@option{x509} or @option{x509verify} options.
1263
1264This option is now deprecated in favor of using the @option{tls-creds}
1265argument.
1266
1267@item x509=@var{/path/to/certificate/dir}
1268
1269Valid if @option{tls} is specified. Require that x509 credentials are used
1270for negotiating the TLS session. The server will send its x509 certificate
1271to the client. It is recommended that a password be set on the VNC server
1272to provide authentication of the client when this is used. The path following
1273this option specifies where the x509 certificates are to be loaded from.
1274See the @ref{vnc_security} section for details on generating certificates.
1275
1276This option is now deprecated in favour of using the @option{tls-creds}
1277argument.
1278
1279@item x509verify=@var{/path/to/certificate/dir}
1280
1281Valid if @option{tls} is specified. Require that x509 credentials are used
1282for negotiating the TLS session. The server will send its x509 certificate
1283to the client, and request that the client send its own x509 certificate.
1284The server will validate the client's certificate against the CA certificate,
1285and reject clients when validation fails. If the certificate authority is
1286trusted, this is a sufficient authentication mechanism. You may still wish
1287to set a password on the VNC server as a second authentication layer. The
1288path following this option specifies where the x509 certificates are to
1289be loaded from. See the @ref{vnc_security} section for details on generating
1290certificates.
1291
1292This option is now deprecated in favour of using the @option{tls-creds}
1293argument.
1294
1295@item sasl
1296
1297Require that the client use SASL to authenticate with the VNC server.
1298The exact choice of authentication method used is controlled from the
1299system / user's SASL configuration file for the 'qemu' service. This
1300is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1301unprivileged user, an environment variable SASL_CONF_PATH can be used
1302to make it search alternate locations for the service config.
1303While some SASL auth methods can also provide data encryption (eg GSSAPI),
1304it is recommended that SASL always be combined with the 'tls' and
1305'x509' settings to enable use of SSL and server certificates. This
1306ensures a data encryption preventing compromise of authentication
1307credentials. See the @ref{vnc_security} section for details on using
1308SASL authentication.
1309
1310@item acl
1311
1312Turn on access control lists for checking of the x509 client certificate
1313and SASL party. For x509 certs, the ACL check is made against the
1314certificate's distinguished name. This is something that looks like
1315@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1316made against the username, which depending on the SASL plugin, may
1317include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1318When the @option{acl} flag is set, the initial access list will be
1319empty, with a @code{deny} policy. Thus no one will be allowed to
1320use the VNC server until the ACLs have been loaded. This can be
1321achieved using the @code{acl} monitor command.
1322
1323@item lossy
1324
1325Enable lossy compression methods (gradient, JPEG, ...). If this
1326option is set, VNC client may receive lossy framebuffer updates
1327depending on its encoding settings. Enabling this option can save
1328a lot of bandwidth at the expense of quality.
1329
1330@item non-adaptive
1331
1332Disable adaptive encodings. Adaptive encodings are enabled by default.
1333An adaptive encoding will try to detect frequently updated screen regions,
1334and send updates in these regions using a lossy encoding (like JPEG).
1335This can be really helpful to save bandwidth when playing videos. Disabling
1336adaptive encodings restores the original static behavior of encodings
1337like Tight.
1338
1339@item share=[allow-exclusive|force-shared|ignore]
1340
1341Set display sharing policy.  'allow-exclusive' allows clients to ask
1342for exclusive access.  As suggested by the rfb spec this is
1343implemented by dropping other connections.  Connecting multiple
1344clients in parallel requires all clients asking for a shared session
1345(vncviewer: -shared switch).  This is the default.  'force-shared'
1346disables exclusive client access.  Useful for shared desktop sessions,
1347where you don't want someone forgetting specify -shared disconnect
1348everybody else.  'ignore' completely ignores the shared flag and
1349allows everybody connect unconditionally.  Doesn't conform to the rfb
1350spec but is traditional QEMU behavior.
1351
1352@end table
1353ETEXI
1354
1355STEXI
1356@end table
1357ETEXI
1358ARCHHEADING(, QEMU_ARCH_I386)
1359
1360ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1361STEXI
1362@table @option
1363ETEXI
1364
1365DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1366    "-win2k-hack     use it when installing Windows 2000 to avoid a disk full bug\n",
1367    QEMU_ARCH_I386)
1368STEXI
1369@item -win2k-hack
1370@findex -win2k-hack
1371Use it when installing Windows 2000 to avoid a disk full bug. After
1372Windows 2000 is installed, you no longer need this option (this option
1373slows down the IDE transfers).
1374ETEXI
1375
1376HXCOMM Deprecated by -rtc
1377DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1378
1379DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1380    "-no-fd-bootchk  disable boot signature checking for floppy disks\n",
1381    QEMU_ARCH_I386)
1382STEXI
1383@item -no-fd-bootchk
1384@findex -no-fd-bootchk
1385Disable boot signature checking for floppy disks in BIOS. May
1386be needed to boot from old floppy disks.
1387ETEXI
1388
1389DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1390           "-no-acpi        disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1391STEXI
1392@item -no-acpi
1393@findex -no-acpi
1394Disable ACPI (Advanced Configuration and Power Interface) support. Use
1395it if your guest OS complains about ACPI problems (PC target machine
1396only).
1397ETEXI
1398
1399DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1400    "-no-hpet        disable HPET\n", QEMU_ARCH_I386)
1401STEXI
1402@item -no-hpet
1403@findex -no-hpet
1404Disable HPET support.
1405ETEXI
1406
1407DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1408    "-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"
1409    "                ACPI table description\n", QEMU_ARCH_I386)
1410STEXI
1411@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}]...]
1412@findex -acpitable
1413Add ACPI table with specified header fields and context from specified files.
1414For file=, take whole ACPI table from the specified files, including all
1415ACPI headers (possible overridden by other options).
1416For data=, only data
1417portion of the table is used, all header information is specified in the
1418command line.
1419ETEXI
1420
1421DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1422    "-smbios file=binary\n"
1423    "                load SMBIOS entry from binary file\n"
1424    "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1425    "              [,uefi=on|off]\n"
1426    "                specify SMBIOS type 0 fields\n"
1427    "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1428    "              [,uuid=uuid][,sku=str][,family=str]\n"
1429    "                specify SMBIOS type 1 fields\n"
1430    "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1431    "              [,asset=str][,location=str]\n"
1432    "                specify SMBIOS type 2 fields\n"
1433    "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1434    "              [,sku=str]\n"
1435    "                specify SMBIOS type 3 fields\n"
1436    "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1437    "              [,asset=str][,part=str]\n"
1438    "                specify SMBIOS type 4 fields\n"
1439    "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1440    "               [,asset=str][,part=str][,speed=%d]\n"
1441    "                specify SMBIOS type 17 fields\n",
1442    QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1443STEXI
1444@item -smbios file=@var{binary}
1445@findex -smbios
1446Load SMBIOS entry from binary file.
1447
1448@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1449Specify SMBIOS type 0 fields
1450
1451@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}]
1452Specify SMBIOS type 1 fields
1453
1454@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}]
1455Specify SMBIOS type 2 fields
1456
1457@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1458Specify SMBIOS type 3 fields
1459
1460@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1461Specify SMBIOS type 4 fields
1462
1463@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}]
1464Specify SMBIOS type 17 fields
1465ETEXI
1466
1467STEXI
1468@end table
1469ETEXI
1470DEFHEADING()
1471
1472DEFHEADING(Network options:)
1473STEXI
1474@table @option
1475ETEXI
1476
1477HXCOMM Legacy slirp options (now moved to -net user):
1478#ifdef CONFIG_SLIRP
1479DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1480DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1481DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1482#ifndef _WIN32
1483DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1484#endif
1485#endif
1486
1487DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1488#ifdef CONFIG_SLIRP
1489    "-netdev user,id=str[,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1490    "         [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n"
1491    "         [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1492#ifndef _WIN32
1493                                             "[,smb=dir[,smbserver=addr]]\n"
1494#endif
1495    "                configure a user mode network backend with ID 'str',\n"
1496    "                its DHCP server and optional services\n"
1497#endif
1498#ifdef _WIN32
1499    "-netdev tap,id=str,ifname=name\n"
1500    "                configure a host TAP network backend with ID 'str'\n"
1501#else
1502    "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1503    "         [,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1504    "         [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1505    "                configure a host TAP network backend with ID 'str'\n"
1506    "                use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1507    "                to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1508    "                to deconfigure it\n"
1509    "                use '[down]script=no' to disable script execution\n"
1510    "                use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1511    "                configure it\n"
1512    "                use 'fd=h' to connect to an already opened TAP interface\n"
1513    "                use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1514    "                use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1515    "                default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1516    "                use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1517    "                use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1518    "                use vhost=on to enable experimental in kernel accelerator\n"
1519    "                    (only has effect for virtio guests which use MSIX)\n"
1520    "                use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1521    "                use 'vhostfd=h' to connect to an already opened vhost net device\n"
1522    "                use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1523    "                use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1524    "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1525    "                configure a host TAP network backend with ID 'str' that is\n"
1526    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1527    "                using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1528#endif
1529#ifdef __linux__
1530    "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1531    "         [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1532    "         [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1533    "         [,rxcookie=rxcookie][,offset=offset]\n"
1534    "                configure a network backend with ID 'str' connected to\n"
1535    "                an Ethernet over L2TPv3 pseudowire.\n"
1536    "                Linux kernel 3.3+ as well as most routers can talk\n"
1537    "                L2TPv3. This transport allows connecting a VM to a VM,\n"
1538    "                VM to a router and even VM to Host. It is a nearly-universal\n"
1539    "                standard (RFC3391). Note - this implementation uses static\n"
1540    "                pre-configured tunnels (same as the Linux kernel).\n"
1541    "                use 'src=' to specify source address\n"
1542    "                use 'dst=' to specify destination address\n"
1543    "                use 'udp=on' to specify udp encapsulation\n"
1544    "                use 'srcport=' to specify source udp port\n"
1545    "                use 'dstport=' to specify destination udp port\n"
1546    "                use 'ipv6=on' to force v6\n"
1547    "                L2TPv3 uses cookies to prevent misconfiguration as\n"
1548    "                well as a weak security measure\n"
1549    "                use 'rxcookie=0x012345678' to specify a rxcookie\n"
1550    "                use 'txcookie=0x012345678' to specify a txcookie\n"
1551    "                use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1552    "                use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1553    "                use 'pincounter=on' to work around broken counter handling in peer\n"
1554    "                use 'offset=X' to add an extra offset between header and data\n"
1555#endif
1556    "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1557    "                configure a network backend to connect to another network\n"
1558    "                using a socket connection\n"
1559    "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1560    "                configure a network backend to connect to a multicast maddr and port\n"
1561    "                use 'localaddr=addr' to specify the host address to send packets from\n"
1562    "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1563    "                configure a network backend to connect to another network\n"
1564    "                using an UDP tunnel\n"
1565#ifdef CONFIG_VDE
1566    "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1567    "                configure a network backend to connect to port 'n' of a vde switch\n"
1568    "                running on host and listening for incoming connections on 'socketpath'.\n"
1569    "                Use group 'groupname' and mode 'octalmode' to change default\n"
1570    "                ownership and permissions for communication port.\n"
1571#endif
1572#ifdef CONFIG_NETMAP
1573    "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1574    "                attach to the existing netmap-enabled network interface 'name', or to a\n"
1575    "                VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1576    "                netmap device, defaults to '/dev/netmap')\n"
1577#endif
1578    "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
1579    "                configure a vhost-user network, backed by a chardev 'dev'\n"
1580    "-netdev hubport,id=str,hubid=n\n"
1581    "                configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL)
1582DEF("net", HAS_ARG, QEMU_OPTION_net,
1583    "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1584    "                old way to create a new NIC and connect it to VLAN 'n'\n"
1585    "                (use the '-device devtype,netdev=str' option if possible instead)\n"
1586    "-net dump[,vlan=n][,file=f][,len=n]\n"
1587    "                dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1588    "-net none       use it alone to have zero network devices. If no -net option\n"
1589    "                is provided, the default is '-net nic -net user'\n"
1590    "-net ["
1591#ifdef CONFIG_SLIRP
1592    "user|"
1593#endif
1594    "tap|"
1595    "bridge|"
1596#ifdef CONFIG_VDE
1597    "vde|"
1598#endif
1599#ifdef CONFIG_NETMAP
1600    "netmap|"
1601#endif
1602    "socket][,vlan=n][,option][,option][,...]\n"
1603    "                old way to initialize a host network interface\n"
1604    "                (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
1605STEXI
1606@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1607@findex -net
1608Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1609= 0 is the default). The NIC is an e1000 by default on the PC
1610target. Optionally, the MAC address can be changed to @var{mac}, the
1611device address set to @var{addr} (PCI cards only),
1612and a @var{name} can be assigned for use in monitor commands.
1613Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1614that the card should have; this option currently only affects virtio cards; set
1615@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1616NIC is created.  QEMU can emulate several different models of network card.
1617Valid values for @var{type} are
1618@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1619@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1620@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1621Not all devices are supported on all targets.  Use @code{-net nic,model=help}
1622for a list of available devices for your target.
1623
1624@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1625@findex -netdev
1626@item -net user[,@var{option}][,@var{option}][,...]
1627Use the user mode network stack which requires no administrator
1628privilege to run. Valid options are:
1629
1630@table @option
1631@item vlan=@var{n}
1632Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1633
1634@item id=@var{id}
1635@itemx name=@var{name}
1636Assign symbolic name for use in monitor commands.
1637
1638@item net=@var{addr}[/@var{mask}]
1639Set IP network address the guest will see. Optionally specify the netmask,
1640either in the form a.b.c.d or as number of valid top-most bits. Default is
164110.0.2.0/24.
1642
1643@item host=@var{addr}
1644Specify the guest-visible address of the host. Default is the 2nd IP in the
1645guest network, i.e. x.x.x.2.
1646
1647@item restrict=on|off
1648If this option is enabled, the guest will be isolated, i.e. it will not be
1649able to contact the host and no guest IP packets will be routed over the host
1650to the outside. This option does not affect any explicitly set forwarding rules.
1651
1652@item hostname=@var{name}
1653Specifies the client hostname reported by the built-in DHCP server.
1654
1655@item dhcpstart=@var{addr}
1656Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1657is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1658
1659@item dns=@var{addr}
1660Specify the guest-visible address of the virtual nameserver. The address must
1661be different from the host address. Default is the 3rd IP in the guest network,
1662i.e. x.x.x.3.
1663
1664@item dnssearch=@var{domain}
1665Provides an entry for the domain-search list sent by the built-in
1666DHCP server. More than one domain suffix can be transmitted by specifying
1667this option multiple times. If supported, this will cause the guest to
1668automatically try to append the given domain suffix(es) in case a domain name
1669can not be resolved.
1670
1671Example:
1672@example
1673qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1674@end example
1675
1676@item tftp=@var{dir}
1677When using the user mode network stack, activate a built-in TFTP
1678server. The files in @var{dir} will be exposed as the root of a TFTP server.
1679The TFTP client on the guest must be configured in binary mode (use the command
1680@code{bin} of the Unix TFTP client).
1681
1682@item bootfile=@var{file}
1683When using the user mode network stack, broadcast @var{file} as the BOOTP
1684filename. In conjunction with @option{tftp}, this can be used to network boot
1685a guest from a local directory.
1686
1687Example (using pxelinux):
1688@example
1689qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1690@end example
1691
1692@item smb=@var{dir}[,smbserver=@var{addr}]
1693When using the user mode network stack, activate a built-in SMB
1694server so that Windows OSes can access to the host files in @file{@var{dir}}
1695transparently. The IP address of the SMB server can be set to @var{addr}. By
1696default the 4th IP in the guest network is used, i.e. x.x.x.4.
1697
1698In the guest Windows OS, the line:
1699@example
170010.0.2.4 smbserver
1701@end example
1702must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1703or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1704
1705Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1706
1707Note that a SAMBA server must be installed on the host OS.
1708QEMU was tested successfully with smbd versions from Red Hat 9,
1709Fedora Core 3 and OpenSUSE 11.x.
1710
1711@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1712Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1713the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1714@var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1715given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1716be bound to a specific host interface. If no connection type is set, TCP is
1717used. This option can be given multiple times.
1718
1719For example, to redirect host X11 connection from screen 1 to guest
1720screen 0, use the following:
1721
1722@example
1723# on the host
1724qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1725# this host xterm should open in the guest X11 server
1726xterm -display :1
1727@end example
1728
1729To redirect telnet connections from host port 5555 to telnet port on
1730the guest, use the following:
1731
1732@example
1733# on the host
1734qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1735telnet localhost 5555
1736@end example
1737
1738Then when you use on the host @code{telnet localhost 5555}, you
1739connect to the guest telnet server.
1740
1741@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1742@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1743Forward guest TCP connections to the IP address @var{server} on port @var{port}
1744to the character device @var{dev} or to a program executed by @var{cmd:command}
1745which gets spawned for each connection. This option can be given multiple times.
1746
1747You can either use a chardev directly and have that one used throughout QEMU's
1748lifetime, like in the following example:
1749
1750@example
1751# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1752# the guest accesses it
1753qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1754@end example
1755
1756Or you can execute a command on every TCP connection established by the guest,
1757so that QEMU behaves similar to an inetd process for that virtual server:
1758
1759@example
1760# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1761# and connect the TCP stream to its stdin/stdout
1762qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1763@end example
1764
1765@end table
1766
1767Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1768processed and applied to -net user. Mixing them with the new configuration
1769syntax gives undefined results. Their use for new applications is discouraged
1770as they will be removed from future versions.
1771
1772@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1773@itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1774Connect the host TAP network interface @var{name} to VLAN @var{n}.
1775
1776Use the network script @var{file} to configure it and the network script
1777@var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1778automatically provides one. The default network configure script is
1779@file{/etc/qemu-ifup} and the default network deconfigure script is
1780@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1781to disable script execution.
1782
1783If running QEMU as an unprivileged user, use the network helper
1784@var{helper} to configure the TAP interface. The default network
1785helper executable is @file{/path/to/qemu-bridge-helper}.
1786
1787@option{fd}=@var{h} can be used to specify the handle of an already
1788opened host TAP interface.
1789
1790Examples:
1791
1792@example
1793#launch a QEMU instance with the default network script
1794qemu-system-i386 linux.img -net nic -net tap
1795@end example
1796
1797@example
1798#launch a QEMU instance with two NICs, each one connected
1799#to a TAP device
1800qemu-system-i386 linux.img \
1801                 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1802                 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1803@end example
1804
1805@example
1806#launch a QEMU instance with the default network helper to
1807#connect a TAP device to bridge br0
1808qemu-system-i386 linux.img \
1809                 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
1810@end example
1811
1812@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1813@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1814Connect a host TAP network interface to a host bridge device.
1815
1816Use the network helper @var{helper} to configure the TAP interface and
1817attach it to the bridge. The default network helper executable is
1818@file{/path/to/qemu-bridge-helper} and the default bridge
1819device is @file{br0}.
1820
1821Examples:
1822
1823@example
1824#launch a QEMU instance with the default network helper to
1825#connect a TAP device to bridge br0
1826qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1827@end example
1828
1829@example
1830#launch a QEMU instance with the default network helper to
1831#connect a TAP device to bridge qemubr0
1832qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1833@end example
1834
1835@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1836@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1837
1838Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1839machine using a TCP socket connection. If @option{listen} is
1840specified, QEMU waits for incoming connections on @var{port}
1841(@var{host} is optional). @option{connect} is used to connect to
1842another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1843specifies an already opened TCP socket.
1844
1845Example:
1846@example
1847# launch a first QEMU instance
1848qemu-system-i386 linux.img \
1849                 -net nic,macaddr=52:54:00:12:34:56 \
1850                 -net socket,listen=:1234
1851# connect the VLAN 0 of this instance to the VLAN 0
1852# of the first instance
1853qemu-system-i386 linux.img \
1854                 -net nic,macaddr=52:54:00:12:34:57 \
1855                 -net socket,connect=127.0.0.1:1234
1856@end example
1857
1858@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1859@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1860
1861Create a VLAN @var{n} shared with another QEMU virtual
1862machines using a UDP multicast socket, effectively making a bus for
1863every QEMU with same multicast address @var{maddr} and @var{port}.
1864NOTES:
1865@enumerate
1866@item
1867Several QEMU can be running on different hosts and share same bus (assuming
1868correct multicast setup for these hosts).
1869@item
1870mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1871@url{http://user-mode-linux.sf.net}.
1872@item
1873Use @option{fd=h} to specify an already opened UDP multicast socket.
1874@end enumerate
1875
1876Example:
1877@example
1878# launch one QEMU instance
1879qemu-system-i386 linux.img \
1880                 -net nic,macaddr=52:54:00:12:34:56 \
1881                 -net socket,mcast=230.0.0.1:1234
1882# launch another QEMU instance on same "bus"
1883qemu-system-i386 linux.img \
1884                 -net nic,macaddr=52:54:00:12:34:57 \
1885                 -net socket,mcast=230.0.0.1:1234
1886# launch yet another QEMU instance on same "bus"
1887qemu-system-i386 linux.img \
1888                 -net nic,macaddr=52:54:00:12:34:58 \
1889                 -net socket,mcast=230.0.0.1:1234
1890@end example
1891
1892Example (User Mode Linux compat.):
1893@example
1894# launch QEMU instance (note mcast address selected
1895# is UML's default)
1896qemu-system-i386 linux.img \
1897                 -net nic,macaddr=52:54:00:12:34:56 \
1898                 -net socket,mcast=239.192.168.1:1102
1899# launch UML
1900/path/to/linux ubd0=/path/to/root_fs eth0=mcast
1901@end example
1902
1903Example (send packets from host's 1.2.3.4):
1904@example
1905qemu-system-i386 linux.img \
1906                 -net nic,macaddr=52:54:00:12:34:56 \
1907                 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1908@end example
1909
1910@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}]
1911@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}]
1912Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
1913protocol to transport Ethernet (and other Layer 2) data frames between
1914two systems. It is present in routers, firewalls and the Linux kernel
1915(from version 3.3 onwards).
1916
1917This transport allows a VM to communicate to another VM, router or firewall directly.
1918
1919@item src=@var{srcaddr}
1920    source address (mandatory)
1921@item dst=@var{dstaddr}
1922    destination address (mandatory)
1923@item udp
1924    select udp encapsulation (default is ip).
1925@item srcport=@var{srcport}
1926    source udp port.
1927@item dstport=@var{dstport}
1928    destination udp port.
1929@item ipv6
1930    force v6, otherwise defaults to v4.
1931@item rxcookie=@var{rxcookie}
1932@itemx txcookie=@var{txcookie}
1933    Cookies are a weak form of security in the l2tpv3 specification.
1934Their function is mostly to prevent misconfiguration. By default they are 32
1935bit.
1936@item cookie64
1937    Set cookie size to 64 bit instead of the default 32
1938@item counter=off
1939    Force a 'cut-down' L2TPv3 with no counter as in
1940draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
1941@item pincounter=on
1942    Work around broken counter handling in peer. This may also help on
1943networks which have packet reorder.
1944@item offset=@var{offset}
1945    Add an extra offset between header and data
1946
1947For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
1948on the remote Linux host 1.2.3.4:
1949@example
1950# Setup tunnel on linux host using raw ip as encapsulation
1951# on 1.2.3.4
1952ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
1953    encap udp udp_sport 16384 udp_dport 16384
1954ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
1955    0xFFFFFFFF peer_session_id 0xFFFFFFFF
1956ifconfig vmtunnel0 mtu 1500
1957ifconfig vmtunnel0 up
1958brctl addif br-lan vmtunnel0
1959
1960
1961# on 4.3.2.1
1962# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
1963
1964qemu-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
1965
1966
1967@end example
1968
1969@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1970@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1971Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1972listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1973and MODE @var{octalmode} to change default ownership and permissions for
1974communication port. This option is only available if QEMU has been compiled
1975with vde support enabled.
1976
1977Example:
1978@example
1979# launch vde switch
1980vde_switch -F -sock /tmp/myswitch
1981# launch QEMU instance
1982qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1983@end example
1984
1985@item -netdev hubport,id=@var{id},hubid=@var{hubid}
1986
1987Create a hub port on QEMU "vlan" @var{hubid}.
1988
1989The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
1990netdev.  @code{-net} and @code{-device} with parameter @option{vlan} create the
1991required hub automatically.
1992
1993@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off]
1994
1995Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
1996be a unix domain socket backed one. The vhost-user uses a specifically defined
1997protocol to pass vhost ioctl replacement messages to an application on the other
1998end of the socket. On non-MSIX guests, the feature can be forced with
1999@var{vhostforce}.
2000
2001Example:
2002@example
2003qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2004     -numa node,memdev=mem \
2005     -chardev socket,path=/path/to/socket \
2006     -netdev type=vhost-user,id=net0,chardev=chr0 \
2007     -device virtio-net-pci,netdev=net0
2008@end example
2009
2010@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2011Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2012At most @var{len} bytes (64k by default) per packet are stored. The file format is
2013libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2014
2015@item -net none
2016Indicate that no network devices should be configured. It is used to
2017override the default configuration (@option{-net nic -net user}) which
2018is activated if no @option{-net} options are provided.
2019ETEXI
2020
2021STEXI
2022@end table
2023ETEXI
2024DEFHEADING()
2025
2026DEFHEADING(Character device options:)
2027STEXI
2028
2029The general form of a character device option is:
2030@table @option
2031ETEXI
2032
2033DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2034    "-chardev null,id=id[,mux=on|off]\n"
2035    "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2036    "         [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (tcp)\n"
2037    "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (unix)\n"
2038    "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2039    "         [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2040    "-chardev msmouse,id=id[,mux=on|off]\n"
2041    "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2042    "         [,mux=on|off]\n"
2043    "-chardev ringbuf,id=id[,size=size]\n"
2044    "-chardev file,id=id,path=path[,mux=on|off]\n"
2045    "-chardev pipe,id=id,path=path[,mux=on|off]\n"
2046#ifdef _WIN32
2047    "-chardev console,id=id[,mux=on|off]\n"
2048    "-chardev serial,id=id,path=path[,mux=on|off]\n"
2049#else
2050    "-chardev pty,id=id[,mux=on|off]\n"
2051    "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
2052#endif
2053#ifdef CONFIG_BRLAPI
2054    "-chardev braille,id=id[,mux=on|off]\n"
2055#endif
2056#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2057        || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2058    "-chardev serial,id=id,path=path[,mux=on|off]\n"
2059    "-chardev tty,id=id,path=path[,mux=on|off]\n"
2060#endif
2061#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2062    "-chardev parallel,id=id,path=path[,mux=on|off]\n"
2063    "-chardev parport,id=id,path=path[,mux=on|off]\n"
2064#endif
2065#if defined(CONFIG_SPICE)
2066    "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
2067    "-chardev spiceport,id=id,name=name[,debug=debug]\n"
2068#endif
2069    , QEMU_ARCH_ALL
2070)
2071
2072STEXI
2073@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2074@findex -chardev
2075Backend is one of:
2076@option{null},
2077@option{socket},
2078@option{udp},
2079@option{msmouse},
2080@option{vc},
2081@option{ringbuf},
2082@option{file},
2083@option{pipe},
2084@option{console},
2085@option{serial},
2086@option{pty},
2087@option{stdio},
2088@option{braille},
2089@option{tty},
2090@option{parallel},
2091@option{parport},
2092@option{spicevmc}.
2093@option{spiceport}.
2094The specific backend will determine the applicable options.
2095
2096All devices must have an id, which can be any string up to 127 characters long.
2097It is used to uniquely identify this device in other command line directives.
2098
2099A character device may be used in multiplexing mode by multiple front-ends.
2100The key sequence of @key{Control-a} and @key{c} will rotate the input focus
2101between attached front-ends. Specify @option{mux=on} to enable this mode.
2102
2103Options to each backend are described below.
2104
2105@item -chardev null ,id=@var{id}
2106A void device. This device will not emit any data, and will drop any data it
2107receives. The null backend does not take any options.
2108
2109@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}]
2110
2111Create a two-way stream socket, which can be either a TCP or a unix socket. A
2112unix socket will be created if @option{path} is specified. Behaviour is
2113undefined if TCP options are specified for a unix socket.
2114
2115@option{server} specifies that the socket shall be a listening socket.
2116
2117@option{nowait} specifies that QEMU should not block waiting for a client to
2118connect to a listening socket.
2119
2120@option{telnet} specifies that traffic on the socket should interpret telnet
2121escape sequences.
2122
2123@option{reconnect} sets the timeout for reconnecting on non-server sockets when
2124the remote end goes away.  qemu will delay this many seconds and then attempt
2125to reconnect.  Zero disables reconnecting, and is the default.
2126
2127TCP and unix socket options are given below:
2128
2129@table @option
2130
2131@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2132
2133@option{host} for a listening socket specifies the local address to be bound.
2134For a connecting socket species the remote host to connect to. @option{host} is
2135optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2136
2137@option{port} for a listening socket specifies the local port to be bound. For a
2138connecting socket specifies the port on the remote host to connect to.
2139@option{port} can be given as either a port number or a service name.
2140@option{port} is required.
2141
2142@option{to} is only relevant to listening sockets. If it is specified, and
2143@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2144to and including @option{to} until it succeeds. @option{to} must be specified
2145as a port number.
2146
2147@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2148If neither is specified the socket may use either protocol.
2149
2150@option{nodelay} disables the Nagle algorithm.
2151
2152@item unix options: path=@var{path}
2153
2154@option{path} specifies the local path of the unix socket. @option{path} is
2155required.
2156
2157@end table
2158
2159@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2160
2161Sends all traffic from the guest to a remote host over UDP.
2162
2163@option{host} specifies the remote host to connect to. If not specified it
2164defaults to @code{localhost}.
2165
2166@option{port} specifies the port on the remote host to connect to. @option{port}
2167is required.
2168
2169@option{localaddr} specifies the local address to bind to. If not specified it
2170defaults to @code{0.0.0.0}.
2171
2172@option{localport} specifies the local port to bind to. If not specified any
2173available local port will be used.
2174
2175@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2176If neither is specified the device may use either protocol.
2177
2178@item -chardev msmouse ,id=@var{id}
2179
2180Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2181take any options.
2182
2183@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2184
2185Connect to a QEMU text console. @option{vc} may optionally be given a specific
2186size.
2187
2188@option{width} and @option{height} specify the width and height respectively of
2189the console, in pixels.
2190
2191@option{cols} and @option{rows} specify that the console be sized to fit a text
2192console with the given dimensions.
2193
2194@item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2195
2196Create a ring buffer with fixed size @option{size}.
2197@var{size} must be a power of two, and defaults to @code{64K}).
2198
2199@item -chardev file ,id=@var{id} ,path=@var{path}
2200
2201Log all traffic received from the guest to a file.
2202
2203@option{path} specifies the path of the file to be opened. This file will be
2204created if it does not already exist, and overwritten if it does. @option{path}
2205is required.
2206
2207@item -chardev pipe ,id=@var{id} ,path=@var{path}
2208
2209Create a two-way connection to the guest. The behaviour differs slightly between
2210Windows hosts and other hosts:
2211
2212On Windows, a single duplex pipe will be created at
2213@file{\\.pipe\@option{path}}.
2214
2215On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2216@file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2217received by the guest. Data written by the guest can be read from
2218@file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2219be present.
2220
2221@option{path} forms part of the pipe path as described above. @option{path} is
2222required.
2223
2224@item -chardev console ,id=@var{id}
2225
2226Send traffic from the guest to QEMU's standard output. @option{console} does not
2227take any options.
2228
2229@option{console} is only available on Windows hosts.
2230
2231@item -chardev serial ,id=@var{id} ,path=@option{path}
2232
2233Send traffic from the guest to a serial device on the host.
2234
2235On Unix hosts serial will actually accept any tty device,
2236not only serial lines.
2237
2238@option{path} specifies the name of the serial device to open.
2239
2240@item -chardev pty ,id=@var{id}
2241
2242Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2243not take any options.
2244
2245@option{pty} is not available on Windows hosts.
2246
2247@item -chardev stdio ,id=@var{id} [,signal=on|off]
2248Connect to standard input and standard output of the QEMU process.
2249
2250@option{signal} controls if signals are enabled on the terminal, that includes
2251exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2252default, use @option{signal=off} to disable it.
2253
2254@option{stdio} is not available on Windows hosts.
2255
2256@item -chardev braille ,id=@var{id}
2257
2258Connect to a local BrlAPI server. @option{braille} does not take any options.
2259
2260@item -chardev tty ,id=@var{id} ,path=@var{path}
2261
2262@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2263DragonFlyBSD hosts.  It is an alias for @option{serial}.
2264
2265@option{path} specifies the path to the tty. @option{path} is required.
2266
2267@item -chardev parallel ,id=@var{id} ,path=@var{path}
2268@itemx -chardev parport ,id=@var{id} ,path=@var{path}
2269
2270@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2271
2272Connect to a local parallel port.
2273
2274@option{path} specifies the path to the parallel port device. @option{path} is
2275required.
2276
2277@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2278
2279@option{spicevmc} is only available when spice support is built in.
2280
2281@option{debug} debug level for spicevmc
2282
2283@option{name} name of spice channel to connect to
2284
2285Connect to a spice virtual machine channel, such as vdiport.
2286
2287@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2288
2289@option{spiceport} is only available when spice support is built in.
2290
2291@option{debug} debug level for spicevmc
2292
2293@option{name} name of spice port to connect to
2294
2295Connect to a spice port, allowing a Spice client to handle the traffic
2296identified by a name (preferably a fqdn).
2297ETEXI
2298
2299STEXI
2300@end table
2301ETEXI
2302DEFHEADING()
2303
2304DEFHEADING(Device URL Syntax:)
2305STEXI
2306
2307In addition to using normal file images for the emulated storage devices,
2308QEMU can also use networked resources such as iSCSI devices. These are
2309specified using a special URL syntax.
2310
2311@table @option
2312@item iSCSI
2313iSCSI support allows QEMU to access iSCSI resources directly and use as
2314images for the guest storage. Both disk and cdrom images are supported.
2315
2316Syntax for specifying iSCSI LUNs is
2317``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2318
2319By default qemu will use the iSCSI initiator-name
2320'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2321line or a configuration file.
2322
2323Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2324stalled requests and force a reestablishment of the session. The timeout
2325is specified in seconds. The default is 0 which means no timeout. Libiscsi
23261.15.0 or greater is required for this feature.
2327
2328Example (without authentication):
2329@example
2330qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2331                 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2332                 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2333@end example
2334
2335Example (CHAP username/password via URL):
2336@example
2337qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2338@end example
2339
2340Example (CHAP username/password via environment variables):
2341@example
2342LIBISCSI_CHAP_USERNAME="user" \
2343LIBISCSI_CHAP_PASSWORD="password" \
2344qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2345@end example
2346
2347iSCSI support is an optional feature of QEMU and only available when
2348compiled and linked against libiscsi.
2349ETEXI
2350DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2351    "-iscsi [user=user][,password=password]\n"
2352    "       [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2353    "       [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2354    "       [,timeout=timeout]\n"
2355    "                iSCSI session parameters\n", QEMU_ARCH_ALL)
2356STEXI
2357
2358iSCSI parameters such as username and password can also be specified via
2359a configuration file. See qemu-doc for more information and examples.
2360
2361@item NBD
2362QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2363as Unix Domain Sockets.
2364
2365Syntax for specifying a NBD device using TCP
2366``nbd:<server-ip>:<port>[:exportname=<export>]''
2367
2368Syntax for specifying a NBD device using Unix Domain Sockets
2369``nbd:unix:<domain-socket>[:exportname=<export>]''
2370
2371
2372Example for TCP
2373@example
2374qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2375@end example
2376
2377Example for Unix Domain Sockets
2378@example
2379qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2380@end example
2381
2382@item SSH
2383QEMU supports SSH (Secure Shell) access to remote disks.
2384
2385Examples:
2386@example
2387qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2388qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2389@end example
2390
2391Currently authentication must be done using ssh-agent.  Other
2392authentication methods may be supported in future.
2393
2394@item Sheepdog
2395Sheepdog is a distributed storage system for QEMU.
2396QEMU supports using either local sheepdog devices or remote networked
2397devices.
2398
2399Syntax for specifying a sheepdog device
2400@example
2401sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2402@end example
2403
2404Example
2405@example
2406qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2407@end example
2408
2409See also @url{http://http://www.osrg.net/sheepdog/}.
2410
2411@item GlusterFS
2412GlusterFS is an user space distributed file system.
2413QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2414TCP, Unix Domain Sockets and RDMA transport protocols.
2415
2416Syntax for specifying a VM disk image on GlusterFS volume is
2417@example
2418gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2419@end example
2420
2421
2422Example
2423@example
2424qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img
2425@end example
2426
2427See also @url{http://www.gluster.org}.
2428
2429@item HTTP/HTTPS/FTP/FTPS/TFTP
2430QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp.
2431
2432Syntax using a single filename:
2433@example
2434<protocol>://[<username>[:<password>]@@]<host>/<path>
2435@end example
2436
2437where:
2438@table @option
2439@item protocol
2440'http', 'https', 'ftp', 'ftps', or 'tftp'.
2441
2442@item username
2443Optional username for authentication to the remote server.
2444
2445@item password
2446Optional password for authentication to the remote server.
2447
2448@item host
2449Address of the remote server.
2450
2451@item path
2452Path on the remote server, including any query string.
2453@end table
2454
2455The following options are also supported:
2456@table @option
2457@item url
2458The full URL when passing options to the driver explicitly.
2459
2460@item readahead
2461The amount of data to read ahead with each range request to the remote server.
2462This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2463does not have a suffix, it will be assumed to be in bytes. The value must be a
2464multiple of 512 bytes. It defaults to 256k.
2465
2466@item sslverify
2467Whether to verify the remote server's certificate when connecting over SSL. It
2468can have the value 'on' or 'off'. It defaults to 'on'.
2469
2470@item cookie
2471Send this cookie (it can also be a list of cookies separated by ';') with
2472each outgoing request.  Only supported when using protocols such as HTTP
2473which support cookies, otherwise ignored.
2474
2475@item timeout
2476Set the timeout in seconds of the CURL connection. This timeout is the time
2477that CURL waits for a response from the remote server to get the size of the
2478image to be downloaded. If not set, the default timeout of 5 seconds is used.
2479@end table
2480
2481Note that when passing options to qemu explicitly, @option{driver} is the value
2482of <protocol>.
2483
2484Example: boot from a remote Fedora 20 live ISO image
2485@example
2486qemu-system-x86_64 --drive media=cdrom,file=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2487
2488qemu-system-x86_64 --drive media=cdrom,file.driver=http,file.url=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2489@end example
2490
2491Example: boot from a remote Fedora 20 cloud image using a local overlay for
2492writes, copy-on-read, and a readahead of 64k
2493@example
2494qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"http",, "file.url":"https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2
2495
2496qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
2497@end example
2498
2499Example: boot from an image stored on a VMware vSphere server with a self-signed
2500certificate using a local overlay for writes, a readahead of 64k and a timeout
2501of 10 seconds.
2502@example
2503qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k",, "file.timeout":10@}' /tmp/test.qcow2
2504
2505qemu-system-x86_64 -drive file=/tmp/test.qcow2
2506@end example
2507ETEXI
2508
2509STEXI
2510@end table
2511ETEXI
2512
2513DEFHEADING(Bluetooth(R) options:)
2514STEXI
2515@table @option
2516ETEXI
2517
2518DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2519    "-bt hci,null    dumb bluetooth HCI - doesn't respond to commands\n" \
2520    "-bt hci,host[:id]\n" \
2521    "                use host's HCI with the given name\n" \
2522    "-bt hci[,vlan=n]\n" \
2523    "                emulate a standard HCI in virtual scatternet 'n'\n" \
2524    "-bt vhci[,vlan=n]\n" \
2525    "                add host computer to virtual scatternet 'n' using VHCI\n" \
2526    "-bt device:dev[,vlan=n]\n" \
2527    "                emulate a bluetooth device 'dev' in scatternet 'n'\n",
2528    QEMU_ARCH_ALL)
2529STEXI
2530@item -bt hci[...]
2531@findex -bt
2532Defines the function of the corresponding Bluetooth HCI.  -bt options
2533are matched with the HCIs present in the chosen machine type.  For
2534example when emulating a machine with only one HCI built into it, only
2535the first @code{-bt hci[...]} option is valid and defines the HCI's
2536logic.  The Transport Layer is decided by the machine type.  Currently
2537the machines @code{n800} and @code{n810} have one HCI and all other
2538machines have none.
2539
2540@anchor{bt-hcis}
2541The following three types are recognized:
2542
2543@table @option
2544@item -bt hci,null
2545(default) The corresponding Bluetooth HCI assumes no internal logic
2546and will not respond to any HCI commands or emit events.
2547
2548@item -bt hci,host[:@var{id}]
2549(@code{bluez} only) The corresponding HCI passes commands / events
2550to / from the physical HCI identified by the name @var{id} (default:
2551@code{hci0}) on the computer running QEMU.  Only available on @code{bluez}
2552capable systems like Linux.
2553
2554@item -bt hci[,vlan=@var{n}]
2555Add a virtual, standard HCI that will participate in the Bluetooth
2556scatternet @var{n} (default @code{0}).  Similarly to @option{-net}
2557VLANs, devices inside a bluetooth network @var{n} can only communicate
2558with other devices in the same network (scatternet).
2559@end table
2560
2561@item -bt vhci[,vlan=@var{n}]
2562(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2563to the host bluetooth stack instead of to the emulated target.  This
2564allows the host and target machines to participate in a common scatternet
2565and communicate.  Requires the Linux @code{vhci} driver installed.  Can
2566be used as following:
2567
2568@example
2569qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2570@end example
2571
2572@item -bt device:@var{dev}[,vlan=@var{n}]
2573Emulate a bluetooth device @var{dev} and place it in network @var{n}
2574(default @code{0}).  QEMU can only emulate one type of bluetooth devices
2575currently:
2576
2577@table @option
2578@item keyboard
2579Virtual wireless keyboard implementing the HIDP bluetooth profile.
2580@end table
2581ETEXI
2582
2583STEXI
2584@end table
2585ETEXI
2586DEFHEADING()
2587
2588#ifdef CONFIG_TPM
2589DEFHEADING(TPM device options:)
2590
2591DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2592    "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2593    "                use path to provide path to a character device; default is /dev/tpm0\n"
2594    "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2595    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2596    QEMU_ARCH_ALL)
2597STEXI
2598
2599The general form of a TPM device option is:
2600@table @option
2601
2602@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2603@findex -tpmdev
2604Backend type must be:
2605@option{passthrough}.
2606
2607The specific backend type will determine the applicable options.
2608The @code{-tpmdev} option creates the TPM backend and requires a
2609@code{-device} option that specifies the TPM frontend interface model.
2610
2611Options to each backend are described below.
2612
2613Use 'help' to print all available TPM backend types.
2614@example
2615qemu -tpmdev help
2616@end example
2617
2618@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2619
2620(Linux-host only) Enable access to the host's TPM using the passthrough
2621driver.
2622
2623@option{path} specifies the path to the host's TPM device, i.e., on
2624a Linux host this would be @code{/dev/tpm0}.
2625@option{path} is optional and by default @code{/dev/tpm0} is used.
2626
2627@option{cancel-path} specifies the path to the host TPM device's sysfs
2628entry allowing for cancellation of an ongoing TPM command.
2629@option{cancel-path} is optional and by default QEMU will search for the
2630sysfs entry to use.
2631
2632Some notes about using the host's TPM with the passthrough driver:
2633
2634The TPM device accessed by the passthrough driver must not be
2635used by any other application on the host.
2636
2637Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2638the VM's firmware (BIOS/UEFI) will not be able to initialize the
2639TPM again and may therefore not show a TPM-specific menu that would
2640otherwise allow the user to configure the TPM, e.g., allow the user to
2641enable/disable or activate/deactivate the TPM.
2642Further, if TPM ownership is released from within a VM then the host's TPM
2643will get disabled and deactivated. To enable and activate the
2644TPM again afterwards, the host has to be rebooted and the user is
2645required to enter the firmware's menu to enable and activate the TPM.
2646If the TPM is left disabled and/or deactivated most TPM commands will fail.
2647
2648To create a passthrough TPM use the following two options:
2649@example
2650-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2651@end example
2652Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2653@code{tpmdev=tpm0} in the device option.
2654
2655@end table
2656
2657ETEXI
2658
2659DEFHEADING()
2660
2661#endif
2662
2663DEFHEADING(Linux/Multiboot boot specific:)
2664STEXI
2665
2666When using these options, you can use a given Linux or Multiboot
2667kernel without installing it in the disk image. It can be useful
2668for easier testing of various kernels.
2669
2670@table @option
2671ETEXI
2672
2673DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2674    "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2675STEXI
2676@item -kernel @var{bzImage}
2677@findex -kernel
2678Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2679or in multiboot format.
2680ETEXI
2681
2682DEF("append", HAS_ARG, QEMU_OPTION_append, \
2683    "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2684STEXI
2685@item -append @var{cmdline}
2686@findex -append
2687Use @var{cmdline} as kernel command line
2688ETEXI
2689
2690DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2691           "-initrd file    use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
2692STEXI
2693@item -initrd @var{file}
2694@findex -initrd
2695Use @var{file} as initial ram disk.
2696
2697@item -initrd "@var{file1} arg=foo,@var{file2}"
2698
2699This syntax is only available with multiboot.
2700
2701Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2702first module.
2703ETEXI
2704
2705DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2706    "-dtb    file    use 'file' as device tree image\n", QEMU_ARCH_ALL)
2707STEXI
2708@item -dtb @var{file}
2709@findex -dtb
2710Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2711on boot.
2712ETEXI
2713
2714STEXI
2715@end table
2716ETEXI
2717DEFHEADING()
2718
2719DEFHEADING(Debug/Expert options:)
2720STEXI
2721@table @option
2722ETEXI
2723
2724DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
2725    "-fw_cfg [name=]<name>,file=<file>\n"
2726    "                add named fw_cfg entry from file\n",
2727    QEMU_ARCH_ALL)
2728STEXI
2729@item -fw_cfg [name=]@var{name},file=@var{file}
2730@findex -fw_cfg
2731Add named fw_cfg entry from file. @var{name} determines the name of
2732the entry in the fw_cfg file directory exposed to the guest.
2733ETEXI
2734
2735DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2736    "-serial dev     redirect the serial port to char device 'dev'\n",
2737    QEMU_ARCH_ALL)
2738STEXI
2739@item -serial @var{dev}
2740@findex -serial
2741Redirect the virtual serial port to host character device
2742@var{dev}. The default device is @code{vc} in graphical mode and
2743@code{stdio} in non graphical mode.
2744
2745This option can be used several times to simulate up to 4 serial
2746ports.
2747
2748Use @code{-serial none} to disable all serial ports.
2749
2750Available character devices are:
2751@table @option
2752@item vc[:@var{W}x@var{H}]
2753Virtual console. Optionally, a width and height can be given in pixel with
2754@example
2755vc:800x600
2756@end example
2757It is also possible to specify width or height in characters:
2758@example
2759vc:80Cx24C
2760@end example
2761@item pty
2762[Linux only] Pseudo TTY (a new PTY is automatically allocated)
2763@item none
2764No device is allocated.
2765@item null
2766void device
2767@item chardev:@var{id}
2768Use a named character device defined with the @code{-chardev} option.
2769@item /dev/XXX
2770[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2771parameters are set according to the emulated ones.
2772@item /dev/parport@var{N}
2773[Linux only, parallel port only] Use host parallel port
2774@var{N}. Currently SPP and EPP parallel port features can be used.
2775@item file:@var{filename}
2776Write output to @var{filename}. No character can be read.
2777@item stdio
2778[Unix only] standard input/output
2779@item pipe:@var{filename}
2780name pipe @var{filename}
2781@item COM@var{n}
2782[Windows only] Use host serial port @var{n}
2783@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2784This implements UDP Net Console.
2785When @var{remote_host} or @var{src_ip} are not specified
2786they default to @code{0.0.0.0}.
2787When not using a specified @var{src_port} a random port is automatically chosen.
2788
2789If you just want a simple readonly console you can use @code{netcat} or
2790@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2791@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2792will appear in the netconsole session.
2793
2794If you plan to send characters back via netconsole or you want to stop
2795and start QEMU a lot of times, you should have QEMU use the same
2796source port each time by using something like @code{-serial
2797udp::4555@@:4556} to QEMU. Another approach is to use a patched
2798version of netcat which can listen to a TCP port and send and receive
2799characters via udp.  If you have a patched version of netcat which
2800activates telnet remote echo and single char transfer, then you can
2801use the following options to step up a netcat redirector to allow
2802telnet on port 5555 to access the QEMU port.
2803@table @code
2804@item QEMU Options:
2805-serial udp::4555@@:4556
2806@item netcat options:
2807-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2808@item telnet options:
2809localhost 5555
2810@end table
2811
2812@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
2813The TCP Net Console has two modes of operation.  It can send the serial
2814I/O to a location or wait for a connection from a location.  By default
2815the TCP Net Console is sent to @var{host} at the @var{port}.  If you use
2816the @var{server} option QEMU will wait for a client socket application
2817to connect to the port before continuing, unless the @code{nowait}
2818option was specified.  The @code{nodelay} option disables the Nagle buffering
2819algorithm.  The @code{reconnect} option only applies if @var{noserver} is
2820set, if the connection goes down it will attempt to reconnect at the
2821given interval.  If @var{host} is omitted, 0.0.0.0 is assumed. Only
2822one TCP connection at a time is accepted. You can use @code{telnet} to
2823connect to the corresponding character device.
2824@table @code
2825@item Example to send tcp console to 192.168.0.2 port 4444
2826-serial tcp:192.168.0.2:4444
2827@item Example to listen and wait on port 4444 for connection
2828-serial tcp::4444,server
2829@item Example to not wait and listen on ip 192.168.0.100 port 4444
2830-serial tcp:192.168.0.100:4444,server,nowait
2831@end table
2832
2833@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2834The telnet protocol is used instead of raw tcp sockets.  The options
2835work the same as if you had specified @code{-serial tcp}.  The
2836difference is that the port acts like a telnet server or client using
2837telnet option negotiation.  This will also allow you to send the
2838MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2839sequence.  Typically in unix telnet you do it with Control-] and then
2840type "send break" followed by pressing the enter key.
2841
2842@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
2843A unix domain socket is used instead of a tcp socket.  The option works the
2844same as if you had specified @code{-serial tcp} except the unix domain socket
2845@var{path} is used for connections.
2846
2847@item mon:@var{dev_string}
2848This is a special option to allow the monitor to be multiplexed onto
2849another serial port.  The monitor is accessed with key sequence of
2850@key{Control-a} and then pressing @key{c}.
2851@var{dev_string} should be any one of the serial devices specified
2852above.  An example to multiplex the monitor onto a telnet server
2853listening on port 4444 would be:
2854@table @code
2855@item -serial mon:telnet::4444,server,nowait
2856@end table
2857When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
2858QEMU any more but will be passed to the guest instead.
2859
2860@item braille
2861Braille device.  This will use BrlAPI to display the braille output on a real
2862or fake device.
2863
2864@item msmouse
2865Three button serial mouse. Configure the guest to use Microsoft protocol.
2866@end table
2867ETEXI
2868
2869DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2870    "-parallel dev   redirect the parallel port to char device 'dev'\n",
2871    QEMU_ARCH_ALL)
2872STEXI
2873@item -parallel @var{dev}
2874@findex -parallel
2875Redirect the virtual parallel port to host device @var{dev} (same
2876devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2877be used to use hardware devices connected on the corresponding host
2878parallel port.
2879
2880This option can be used several times to simulate up to 3 parallel
2881ports.
2882
2883Use @code{-parallel none} to disable all parallel ports.
2884ETEXI
2885
2886DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2887    "-monitor dev    redirect the monitor to char device 'dev'\n",
2888    QEMU_ARCH_ALL)
2889STEXI
2890@item -monitor @var{dev}
2891@findex -monitor
2892Redirect the monitor to host device @var{dev} (same devices as the
2893serial port).
2894The default device is @code{vc} in graphical mode and @code{stdio} in
2895non graphical mode.
2896Use @code{-monitor none} to disable the default monitor.
2897ETEXI
2898DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2899    "-qmp dev        like -monitor but opens in 'control' mode\n",
2900    QEMU_ARCH_ALL)
2901STEXI
2902@item -qmp @var{dev}
2903@findex -qmp
2904Like -monitor but opens in 'control' mode.
2905ETEXI
2906DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
2907    "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
2908    QEMU_ARCH_ALL)
2909STEXI
2910@item -qmp-pretty @var{dev}
2911@findex -qmp-pretty
2912Like -qmp but uses pretty JSON formatting.
2913ETEXI
2914
2915DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2916    "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2917STEXI
2918@item -mon [chardev=]name[,mode=readline|control][,default]
2919@findex -mon
2920Setup monitor on chardev @var{name}.
2921ETEXI
2922
2923DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2924    "-debugcon dev   redirect the debug console to char device 'dev'\n",
2925    QEMU_ARCH_ALL)
2926STEXI
2927@item -debugcon @var{dev}
2928@findex -debugcon
2929Redirect the debug console to host device @var{dev} (same devices as the
2930serial port).  The debug console is an I/O port which is typically port
29310xe9; writing to that I/O port sends output to this device.
2932The default device is @code{vc} in graphical mode and @code{stdio} in
2933non graphical mode.
2934ETEXI
2935
2936DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2937    "-pidfile file   write PID to 'file'\n", QEMU_ARCH_ALL)
2938STEXI
2939@item -pidfile @var{file}
2940@findex -pidfile
2941Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2942from a script.
2943ETEXI
2944
2945DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2946    "-singlestep     always run in singlestep mode\n", QEMU_ARCH_ALL)
2947STEXI
2948@item -singlestep
2949@findex -singlestep
2950Run the emulation in single step mode.
2951ETEXI
2952
2953DEF("S", 0, QEMU_OPTION_S, \
2954    "-S              freeze CPU at startup (use 'c' to start execution)\n",
2955    QEMU_ARCH_ALL)
2956STEXI
2957@item -S
2958@findex -S
2959Do not start CPU at startup (you must type 'c' in the monitor).
2960ETEXI
2961
2962DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
2963    "-realtime [mlock=on|off]\n"
2964    "                run qemu with realtime features\n"
2965    "                mlock=on|off controls mlock support (default: on)\n",
2966    QEMU_ARCH_ALL)
2967STEXI
2968@item -realtime mlock=on|off
2969@findex -realtime
2970Run qemu with realtime features.
2971mlocking qemu and guest memory can be enabled via @option{mlock=on}
2972(enabled by default).
2973ETEXI
2974
2975DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2976    "-gdb dev        wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
2977STEXI
2978@item -gdb @var{dev}
2979@findex -gdb
2980Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2981connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2982stdio are reasonable use case. The latter is allowing to start QEMU from
2983within gdb and establish the connection via a pipe:
2984@example
2985(gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2986@end example
2987ETEXI
2988
2989DEF("s", 0, QEMU_OPTION_s, \
2990    "-s              shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2991    QEMU_ARCH_ALL)
2992STEXI
2993@item -s
2994@findex -s
2995Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2996(@pxref{gdb_usage}).
2997ETEXI
2998
2999DEF("d", HAS_ARG, QEMU_OPTION_d, \
3000    "-d item1,...    enable logging of specified items (use '-d help' for a list of log items)\n",
3001    QEMU_ARCH_ALL)
3002STEXI
3003@item -d @var{item1}[,...]
3004@findex -d
3005Enable logging of specified items. Use '-d help' for a list of log items.
3006ETEXI
3007
3008DEF("D", HAS_ARG, QEMU_OPTION_D, \
3009    "-D logfile      output log to logfile (default stderr)\n",
3010    QEMU_ARCH_ALL)
3011STEXI
3012@item -D @var{logfile}
3013@findex -D
3014Output log in @var{logfile} instead of to stderr
3015ETEXI
3016
3017DEF("L", HAS_ARG, QEMU_OPTION_L, \
3018    "-L path         set the directory for the BIOS, VGA BIOS and keymaps\n",
3019    QEMU_ARCH_ALL)
3020STEXI
3021@item -L  @var{path}
3022@findex -L
3023Set the directory for the BIOS, VGA BIOS and keymaps.
3024ETEXI
3025
3026DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3027    "-bios file      set the filename for the BIOS\n", QEMU_ARCH_ALL)
3028STEXI
3029@item -bios @var{file}
3030@findex -bios
3031Set the filename for the BIOS.
3032ETEXI
3033
3034DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3035    "-enable-kvm     enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3036STEXI
3037@item -enable-kvm
3038@findex -enable-kvm
3039Enable KVM full virtualization support. This option is only available
3040if KVM support is enabled when compiling.
3041ETEXI
3042
3043DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3044    "-xen-domid id   specify xen guest domain id\n", QEMU_ARCH_ALL)
3045DEF("xen-create", 0, QEMU_OPTION_xen_create,
3046    "-xen-create     create domain using xen hypercalls, bypassing xend\n"
3047    "                warning: should not be used when xend is in use\n",
3048    QEMU_ARCH_ALL)
3049DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3050    "-xen-attach     attach to existing xen domain\n"
3051    "                xend will use this when starting QEMU\n",
3052    QEMU_ARCH_ALL)
3053STEXI
3054@item -xen-domid @var{id}
3055@findex -xen-domid
3056Specify xen guest domain @var{id} (XEN only).
3057@item -xen-create
3058@findex -xen-create
3059Create domain using xen hypercalls, bypassing xend.
3060Warning: should not be used when xend is in use (XEN only).
3061@item -xen-attach
3062@findex -xen-attach
3063Attach to existing xen domain.
3064xend will use this when starting QEMU (XEN only).
3065ETEXI
3066
3067DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3068    "-no-reboot      exit instead of rebooting\n", QEMU_ARCH_ALL)
3069STEXI
3070@item -no-reboot
3071@findex -no-reboot
3072Exit instead of rebooting.
3073ETEXI
3074
3075DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3076    "-no-shutdown    stop before shutdown\n", QEMU_ARCH_ALL)
3077STEXI
3078@item -no-shutdown
3079@findex -no-shutdown
3080Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3081This allows for instance switching to monitor to commit changes to the
3082disk image.
3083ETEXI
3084
3085DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3086    "-loadvm [tag|id]\n" \
3087    "                start right away with a saved state (loadvm in monitor)\n",
3088    QEMU_ARCH_ALL)
3089STEXI
3090@item -loadvm @var{file}
3091@findex -loadvm
3092Start right away with a saved state (@code{loadvm} in monitor)
3093ETEXI
3094
3095#ifndef _WIN32
3096DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3097    "-daemonize      daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3098#endif
3099STEXI
3100@item -daemonize
3101@findex -daemonize
3102Daemonize the QEMU process after initialization.  QEMU will not detach from
3103standard IO until it is ready to receive connections on any of its devices.
3104This option is a useful way for external programs to launch QEMU without having
3105to cope with initialization race conditions.
3106ETEXI
3107
3108DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3109    "-option-rom rom load a file, rom, into the option ROM space\n",
3110    QEMU_ARCH_ALL)
3111STEXI
3112@item -option-rom @var{file}
3113@findex -option-rom
3114Load the contents of @var{file} as an option ROM.
3115This option is useful to load things like EtherBoot.
3116ETEXI
3117
3118HXCOMM Silently ignored for compatibility
3119DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3120
3121HXCOMM Options deprecated by -rtc
3122DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3123DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3124
3125DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3126    "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3127    "                set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3128    QEMU_ARCH_ALL)
3129
3130STEXI
3131
3132@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3133@findex -rtc
3134Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3135UTC or local time, respectively. @code{localtime} is required for correct date in
3136MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3137format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3138
3139By default the RTC is driven by the host system time. This allows using of the
3140RTC as accurate reference clock inside the guest, specifically if the host
3141time is smoothly following an accurate external reference clock, e.g. via NTP.
3142If you want to isolate the guest time from the host, you can set @option{clock}
3143to @code{rt} instead.  To even prevent it from progressing during suspension,
3144you can set it to @code{vm}.
3145
3146Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3147specifically with Windows' ACPI HAL. This option will try to figure out how
3148many timer interrupts were not processed by the Windows guest and will
3149re-inject them.
3150ETEXI
3151
3152DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3153    "-icount [shift=N|auto][,align=on|off][,sleep=no]\n" \
3154    "                enable virtual instruction counter with 2^N clock ticks per\n" \
3155    "                instruction, enable aligning the host and virtual clocks\n" \
3156    "                or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3157STEXI
3158@item -icount [shift=@var{N}|auto]
3159@findex -icount
3160Enable virtual instruction counter.  The virtual cpu will execute one
3161instruction every 2^@var{N} ns of virtual time.  If @code{auto} is specified
3162then the virtual cpu speed will be automatically adjusted to keep virtual
3163time within a few seconds of real time.
3164
3165When the virtual cpu is sleeping, the virtual time will advance at default
3166speed unless @option{sleep=no} is specified.
3167With @option{sleep=no}, the virtual time will jump to the next timer deadline
3168instantly whenever the virtual cpu goes to sleep mode and will not advance
3169if no timer is enabled. This behavior give deterministic execution times from
3170the guest point of view.
3171
3172Note that while this option can give deterministic behavior, it does not
3173provide cycle accurate emulation.  Modern CPUs contain superscalar out of
3174order cores with complex cache hierarchies.  The number of instructions
3175executed often has little or no correlation with actual performance.
3176
3177@option{align=on} will activate the delay algorithm which will try
3178to synchronise the host clock and the virtual clock. The goal is to
3179have a guest running at the real frequency imposed by the shift option.
3180Whenever the guest clock is behind the host clock and if
3181@option{align=on} is specified then we print a message to the user
3182to inform about the delay.
3183Currently this option does not work when @option{shift} is @code{auto}.
3184Note: The sync algorithm will work for those shift values for which
3185the guest clock runs ahead of the host clock. Typically this happens
3186when the shift value is high (how high depends on the host machine).
3187ETEXI
3188
3189DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3190    "-watchdog model\n" \
3191    "                enable virtual hardware watchdog [default=none]\n",
3192    QEMU_ARCH_ALL)
3193STEXI
3194@item -watchdog @var{model}
3195@findex -watchdog
3196Create a virtual hardware watchdog device.  Once enabled (by a guest
3197action), the watchdog must be periodically polled by an agent inside
3198the guest or else the guest will be restarted. Choose a model for
3199which your guest has drivers.
3200
3201The @var{model} is the model of hardware watchdog to emulate. Use
3202@code{-watchdog help} to list available hardware models. Only one
3203watchdog can be enabled for a guest.
3204
3205The following models may be available:
3206@table @option
3207@item ib700
3208iBASE 700 is a very simple ISA watchdog with a single timer.
3209@item i6300esb
3210Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3211dual-timer watchdog.
3212@item diag288
3213A virtual watchdog for s390x backed by the diagnose 288 hypercall
3214(currently KVM only).
3215@end table
3216ETEXI
3217
3218DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3219    "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
3220    "                action when watchdog fires [default=reset]\n",
3221    QEMU_ARCH_ALL)
3222STEXI
3223@item -watchdog-action @var{action}
3224@findex -watchdog-action
3225
3226The @var{action} controls what QEMU will do when the watchdog timer
3227expires.
3228The default is
3229@code{reset} (forcefully reset the guest).
3230Other possible actions are:
3231@code{shutdown} (attempt to gracefully shutdown the guest),
3232@code{poweroff} (forcefully poweroff the guest),
3233@code{pause} (pause the guest),
3234@code{debug} (print a debug message and continue), or
3235@code{none} (do nothing).
3236
3237Note that the @code{shutdown} action requires that the guest responds
3238to ACPI signals, which it may not be able to do in the sort of
3239situations where the watchdog would have expired, and thus
3240@code{-watchdog-action shutdown} is not recommended for production use.
3241
3242Examples:
3243
3244@table @code
3245@item -watchdog i6300esb -watchdog-action pause
3246@itemx -watchdog ib700
3247@end table
3248ETEXI
3249
3250DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3251    "-echr chr       set terminal escape character instead of ctrl-a\n",
3252    QEMU_ARCH_ALL)
3253STEXI
3254
3255@item -echr @var{numeric_ascii_value}
3256@findex -echr
3257Change the escape character used for switching to the monitor when using
3258monitor and serial sharing.  The default is @code{0x01} when using the
3259@code{-nographic} option.  @code{0x01} is equal to pressing
3260@code{Control-a}.  You can select a different character from the ascii
3261control keys where 1 through 26 map to Control-a through Control-z.  For
3262instance you could use the either of the following to change the escape
3263character to Control-t.
3264@table @code
3265@item -echr 0x14
3266@itemx -echr 20
3267@end table
3268ETEXI
3269
3270DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3271    "-virtioconsole c\n" \
3272    "                set virtio console\n", QEMU_ARCH_ALL)
3273STEXI
3274@item -virtioconsole @var{c}
3275@findex -virtioconsole
3276Set virtio console.
3277
3278This option is maintained for backward compatibility.
3279
3280Please use @code{-device virtconsole} for the new way of invocation.
3281ETEXI
3282
3283DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3284    "-show-cursor    show cursor\n", QEMU_ARCH_ALL)
3285STEXI
3286@item -show-cursor
3287@findex -show-cursor
3288Show cursor.
3289ETEXI
3290
3291DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3292    "-tb-size n      set TB size\n", QEMU_ARCH_ALL)
3293STEXI
3294@item -tb-size @var{n}
3295@findex -tb-size
3296Set TB size.
3297ETEXI
3298
3299DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3300    "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3301    "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3302    "-incoming unix:socketpath\n" \
3303    "                prepare for incoming migration, listen on\n" \
3304    "                specified protocol and socket address\n" \
3305    "-incoming fd:fd\n" \
3306    "-incoming exec:cmdline\n" \
3307    "                accept incoming migration on given file descriptor\n" \
3308    "                or from given external command\n" \
3309    "-incoming defer\n" \
3310    "                wait for the URI to be specified via migrate_incoming\n",
3311    QEMU_ARCH_ALL)
3312STEXI
3313@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3314@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3315@findex -incoming
3316Prepare for incoming migration, listen on a given tcp port.
3317
3318@item -incoming unix:@var{socketpath}
3319Prepare for incoming migration, listen on a given unix socket.
3320
3321@item -incoming fd:@var{fd}
3322Accept incoming migration from a given filedescriptor.
3323
3324@item -incoming exec:@var{cmdline}
3325Accept incoming migration as an output from specified external command.
3326
3327@item -incoming defer
3328Wait for the URI to be specified via migrate_incoming.  The monitor can
3329be used to change settings (such as migration parameters) prior to issuing
3330the migrate_incoming to allow the migration to begin.
3331ETEXI
3332
3333DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3334    "-nodefaults     don't create default devices\n", QEMU_ARCH_ALL)
3335STEXI
3336@item -nodefaults
3337@findex -nodefaults
3338Don't create default devices. Normally, QEMU sets the default devices like serial
3339port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3340CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3341default devices.
3342ETEXI
3343
3344#ifndef _WIN32
3345DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3346    "-chroot dir     chroot to dir just before starting the VM\n",
3347    QEMU_ARCH_ALL)
3348#endif
3349STEXI
3350@item -chroot @var{dir}
3351@findex -chroot
3352Immediately before starting guest execution, chroot to the specified
3353directory.  Especially useful in combination with -runas.
3354ETEXI
3355
3356#ifndef _WIN32
3357DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3358    "-runas user     change to user id user just before starting the VM\n",
3359    QEMU_ARCH_ALL)
3360#endif
3361STEXI
3362@item -runas @var{user}
3363@findex -runas
3364Immediately before starting guest execution, drop root privileges, switching
3365to the specified user.
3366ETEXI
3367
3368DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3369    "-prom-env variable=value\n"
3370    "                set OpenBIOS nvram variables\n",
3371    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3372STEXI
3373@item -prom-env @var{variable}=@var{value}
3374@findex -prom-env
3375Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3376ETEXI
3377DEF("semihosting", 0, QEMU_OPTION_semihosting,
3378    "-semihosting    semihosting mode\n",
3379    QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3380    QEMU_ARCH_MIPS)
3381STEXI
3382@item -semihosting
3383@findex -semihosting
3384Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3385ETEXI
3386DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3387    "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3388    "                semihosting configuration\n",
3389QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3390QEMU_ARCH_MIPS)
3391STEXI
3392@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3393@findex -semihosting-config
3394Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3395@table @option
3396@item target=@code{native|gdb|auto}
3397Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3398or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3399during debug sessions and @code{native} otherwise.
3400@item arg=@var{str1},arg=@var{str2},...
3401Allows the user to pass input arguments, and can be used multiple times to build
3402up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3403command line is still supported for backward compatibility. If both the
3404@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3405specified, the former is passed to semihosting as it always takes precedence.
3406@end table
3407ETEXI
3408DEF("old-param", 0, QEMU_OPTION_old_param,
3409    "-old-param      old param mode\n", QEMU_ARCH_ARM)
3410STEXI
3411@item -old-param
3412@findex -old-param (ARM)
3413Old param mode (ARM only).
3414ETEXI
3415
3416DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3417    "-sandbox <arg>  Enable seccomp mode 2 system call filter (default 'off').\n",
3418    QEMU_ARCH_ALL)
3419STEXI
3420@item -sandbox @var{arg}
3421@findex -sandbox
3422Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3423disable it.  The default is 'off'.
3424ETEXI
3425
3426DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3427    "-readconfig <file>\n", QEMU_ARCH_ALL)
3428STEXI
3429@item -readconfig @var{file}
3430@findex -readconfig
3431Read device configuration from @var{file}. This approach is useful when you want to spawn
3432QEMU process with many command line options but you don't want to exceed the command line
3433character limit.
3434ETEXI
3435DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3436    "-writeconfig <file>\n"
3437    "                read/write config file\n", QEMU_ARCH_ALL)
3438STEXI
3439@item -writeconfig @var{file}
3440@findex -writeconfig
3441Write device configuration to @var{file}. The @var{file} can be either filename to save
3442command line and device configuration into file or dash @code{-}) character to print the
3443output to stdout. This can be later used as input file for @code{-readconfig} option.
3444ETEXI
3445DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3446    "-nodefconfig\n"
3447    "                do not load default config files at startup\n",
3448    QEMU_ARCH_ALL)
3449STEXI
3450@item -nodefconfig
3451@findex -nodefconfig
3452Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3453The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3454ETEXI
3455DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3456    "-no-user-config\n"
3457    "                do not load user-provided config files at startup\n",
3458    QEMU_ARCH_ALL)
3459STEXI
3460@item -no-user-config
3461@findex -no-user-config
3462The @code{-no-user-config} option makes QEMU not load any of the user-provided
3463config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
3464files from @var{datadir}.
3465ETEXI
3466DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3467    "-trace [events=<file>][,file=<file>]\n"
3468    "                specify tracing options\n",
3469    QEMU_ARCH_ALL)
3470STEXI
3471HXCOMM This line is not accurate, as some sub-options are backend-specific but
3472HXCOMM HX does not support conditional compilation of text.
3473@item -trace [events=@var{file}][,file=@var{file}]
3474@findex -trace
3475
3476Specify tracing options.
3477
3478@table @option
3479@item events=@var{file}
3480Immediately enable events listed in @var{file}.
3481The file must contain one event name (as listed in the @var{trace-events} file)
3482per line.
3483This option is only available if QEMU has been compiled with
3484either @var{simple} or @var{stderr} tracing backend.
3485@item file=@var{file}
3486Log output traces to @var{file}.
3487
3488This option is only available if QEMU has been compiled with
3489the @var{simple} tracing backend.
3490@end table
3491ETEXI
3492
3493HXCOMM Internal use
3494DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3495DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3496
3497#ifdef __linux__
3498DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3499    "-enable-fips    enable FIPS 140-2 compliance\n",
3500    QEMU_ARCH_ALL)
3501#endif
3502STEXI
3503@item -enable-fips
3504@findex -enable-fips
3505Enable FIPS 140-2 compliance mode.
3506ETEXI
3507
3508HXCOMM Deprecated by -machine accel=tcg property
3509DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3510
3511HXCOMM Deprecated by kvm-pit driver properties
3512DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3513    "", QEMU_ARCH_I386)
3514
3515HXCOMM Deprecated (ignored)
3516DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3517
3518HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3519DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3520
3521HXCOMM Deprecated (ignored)
3522DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3523
3524DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3525    "-msg timestamp[=on|off]\n"
3526    "                change the format of messages\n"
3527    "                on|off controls leading timestamps (default:on)\n",
3528    QEMU_ARCH_ALL)
3529STEXI
3530@item -msg timestamp[=on|off]
3531@findex -msg
3532prepend a timestamp to each log message.(default:on)
3533ETEXI
3534
3535DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3536    "-dump-vmstate <file>\n"
3537    "                Output vmstate information in JSON format to file.\n"
3538    "                Use the scripts/vmstate-static-checker.py file to\n"
3539    "                check for possible regressions in migration code\n"
3540    "                by comparing two such vmstate dumps.\n",
3541    QEMU_ARCH_ALL)
3542STEXI
3543@item -dump-vmstate @var{file}
3544@findex -dump-vmstate
3545Dump json-encoded vmstate information for current machine type to file
3546in @var{file}
3547ETEXI
3548
3549DEFHEADING(Generic object creation)
3550
3551DEF("object", HAS_ARG, QEMU_OPTION_object,
3552    "-object TYPENAME[,PROP1=VALUE1,...]\n"
3553    "                create a new object of type TYPENAME setting properties\n"
3554    "                in the order they are specified.  Note that the 'id'\n"
3555    "                property must be set.  These objects are placed in the\n"
3556    "                '/objects' path.\n",
3557    QEMU_ARCH_ALL)
3558STEXI
3559@item -object @var{typename}[,@var{prop1}=@var{value1},...]
3560@findex -object
3561Create a new object of type @var{typename} setting properties
3562in the order they are specified.  Note that the 'id'
3563property must be set.  These objects are placed in the
3564'/objects' path.
3565
3566@table @option
3567
3568@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off}
3569
3570Creates a memory file backend object, which can be used to back
3571the guest RAM with huge pages. The @option{id} parameter is a
3572unique ID that will be used to reference this memory region
3573when configuring the @option{-numa} argument. The @option{size}
3574option provides the size of the memory region, and accepts
3575common suffixes, eg @option{500M}. The @option{mem-path} provides
3576the path to either a shared memory or huge page filesystem mount.
3577The @option{share} boolean option determines whether the memory
3578region is marked as private to QEMU, or shared. The latter allows
3579a co-operating external process to access the QEMU memory region.
3580
3581@item -object rng-random,id=@var{id},filename=@var{/dev/random}
3582
3583Creates a random number generator backend which obtains entropy from
3584a device on the host. The @option{id} parameter is a unique ID that
3585will be used to reference this entropy backend from the @option{virtio-rng}
3586device. The @option{filename} parameter specifies which file to obtain
3587entropy from and if omitted defaults to @option{/dev/random}.
3588
3589@item -object rng-egd,id=@var{id},chardev=@var{chardevid}
3590
3591Creates a random number generator backend which obtains entropy from
3592an external daemon running on the host. The @option{id} parameter is
3593a unique ID that will be used to reference this entropy backend from
3594the @option{virtio-rng} device. The @option{chardev} parameter is
3595the unique ID of a character device backend that provides the connection
3596to the RNG daemon.
3597
3598@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
3599
3600Creates a TLS anonymous credentials object, which can be used to provide
3601TLS support on network backends. The @option{id} parameter is a unique
3602ID which network backends will use to access the credentials. The
3603@option{endpoint} is either @option{server} or @option{client} depending
3604on whether the QEMU network backend that uses the credentials will be
3605acting as a client or as a server. If @option{verify-peer} is enabled
3606(the default) then once the handshake is completed, the peer credentials
3607will be verified, though this is a no-op for anonymous credentials.
3608
3609The @var{dir} parameter tells QEMU where to find the credential
3610files. For server endpoints, this directory may contain a file
3611@var{dh-params.pem} providing diffie-hellman parameters to use
3612for the TLS server. If the file is missing, QEMU will generate
3613a set of DH parameters at startup. This is a computationally
3614expensive operation that consumes random pool entropy, so it is
3615recommended that a persistent set of parameters be generated
3616upfront and saved.
3617
3618@item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
3619
3620Creates a TLS anonymous credentials object, which can be used to provide
3621TLS support on network backends. The @option{id} parameter is a unique
3622ID which network backends will use to access the credentials. The
3623@option{endpoint} is either @option{server} or @option{client} depending
3624on whether the QEMU network backend that uses the credentials will be
3625acting as a client or as a server. If @option{verify-peer} is enabled
3626(the default) then once the handshake is completed, the peer credentials
3627will be verified. With x509 certificates, this implies that the clients
3628must be provided with valid client certificates too.
3629
3630The @var{dir} parameter tells QEMU where to find the credential
3631files. For server endpoints, this directory may contain a file
3632@var{dh-params.pem} providing diffie-hellman parameters to use
3633for the TLS server. If the file is missing, QEMU will generate
3634a set of DH parameters at startup. This is a computationally
3635expensive operation that consumes random pool entropy, so it is
3636recommended that a persistent set of parameters be generated
3637upfront and saved.
3638
3639For x509 certificate credentials the directory will contain further files
3640providing the x509 certificates. The certificates must be stored
3641in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
3642@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
3643@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
3644
3645@end table
3646
3647ETEXI
3648
3649
3650HXCOMM This is the last statement. Insert new options before this line!
3651STEXI
3652@end table
3653ETEXI
3654