1HXCOMM Use DEFHEADING() to define headings in both help text and texi 2HXCOMM Text between STEXI and ETEXI are copied to texi version and 3HXCOMM discarded from C version 4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to 5HXCOMM construct option structures, enums and help message for specified 6HXCOMM architectures. 7HXCOMM HXCOMM can be used for comments, discarded from both texi and C 8 9DEFHEADING(Standard options:) 10STEXI 11@table @option 12ETEXI 13 14DEF("help", 0, QEMU_OPTION_h, 15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL) 16STEXI 17@item -h 18@findex -h 19Display help and exit 20ETEXI 21 22DEF("version", 0, QEMU_OPTION_version, 23 "-version display version information and exit\n", QEMU_ARCH_ALL) 24STEXI 25@item -version 26@findex -version 27Display version information and exit 28ETEXI 29 30DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ 31 "-machine [type=]name[,prop[=value][,...]]\n" 32 " selects emulated machine ('-machine help' for list)\n" 33 " property accel=accel1[:accel2[:...]] selects accelerator\n" 34 " supported accelerators are kvm, xen, hax, hvf, whpx or tcg (default: tcg)\n" 35 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n" 36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n" 37 " kvm_shadow_mem=size of KVM shadow MMU in bytes\n" 38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 39 " mem-merge=on|off controls memory merge support (default: on)\n" 40 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n" 41 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" 42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" 43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" 44 " nvdimm=on|off controls NVDIMM support (default=off)\n" 45 " enforce-config-section=on|off enforce configuration section migration (default=off)\n" 46 " memory-encryption=@var{} memory encryption object to use (default=none)\n", 47 QEMU_ARCH_ALL) 48STEXI 49@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 50@findex -machine 51Select the emulated machine by @var{name}. Use @code{-machine help} to list 52available machines. 53 54For architectures which aim to support live migration compatibility 55across releases, each release will introduce a new versioned machine 56type. For example, the 2.8.0 release introduced machine types 57``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures. 58 59To allow live migration of guests from QEMU version 2.8.0, to QEMU 60version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8'' 61and ``pc-q35-2.8'' machines too. To allow users live migrating VMs 62to skip multiple intermediate releases when upgrading, new releases 63of QEMU will support machine types from many previous versions. 64 65Supported machine properties are: 66@table @option 67@item accel=@var{accels1}[:@var{accels2}[:...]] 68This is used to enable an accelerator. Depending on the target architecture, 69kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 70more than one accelerator specified, the next one is used if the previous one 71fails to initialize. 72@item kernel_irqchip=on|off 73Controls in-kernel irqchip support for the chosen accelerator when available. 74@item gfx_passthru=on|off 75Enables IGD GFX passthrough support for the chosen machine when available. 76@item vmport=on|off|auto 77Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 78value based on accel. For accel=xen the default is off otherwise the default 79is on. 80@item kvm_shadow_mem=size 81Defines the size of the KVM shadow MMU. 82@item dump-guest-core=on|off 83Include guest memory in a core dump. The default is on. 84@item mem-merge=on|off 85Enables or disables memory merge support. This feature, when supported by 86the host, de-duplicates identical memory pages among VMs instances 87(enabled by default). 88@item aes-key-wrap=on|off 89Enables or disables AES key wrapping support on s390-ccw hosts. This feature 90controls whether AES wrapping keys will be created to allow 91execution of AES cryptographic functions. The default is on. 92@item dea-key-wrap=on|off 93Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 94controls whether DEA wrapping keys will be created to allow 95execution of DEA cryptographic functions. The default is on. 96@item nvdimm=on|off 97Enables or disables NVDIMM support. The default is off. 98@item enforce-config-section=on|off 99If @option{enforce-config-section} is set to @var{on}, force migration 100code to send configuration section even if the machine-type sets the 101@option{migration.send-configuration} property to @var{off}. 102NOTE: this parameter is deprecated. Please use @option{-global} 103@option{migration.send-configuration}=@var{on|off} instead. 104@item memory-encryption=@var{} 105Memory encryption object to use. The default is none. 106@end table 107ETEXI 108 109HXCOMM Deprecated by -machine 110DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 111 112DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 113 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 114STEXI 115@item -cpu @var{model} 116@findex -cpu 117Select CPU model (@code{-cpu help} for list and additional feature selection) 118ETEXI 119 120DEF("accel", HAS_ARG, QEMU_OPTION_accel, 121 "-accel [accel=]accelerator[,thread=single|multi]\n" 122 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n" 123 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL) 124STEXI 125@item -accel @var{name}[,prop=@var{value}[,...]] 126@findex -accel 127This is used to enable an accelerator. Depending on the target architecture, 128kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 129more than one accelerator specified, the next one is used if the previous one 130fails to initialize. 131@table @option 132@item thread=single|multi 133Controls number of TCG threads. When the TCG is multi-threaded there will be one 134thread per vCPU therefor taking advantage of additional host cores. The default 135is to enable multi-threading where both the back-end and front-ends support it and 136no incompatible TCG features have been enabled (e.g. icount/replay). 137@end table 138ETEXI 139 140DEF("smp", HAS_ARG, QEMU_OPTION_smp, 141 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,dies=dies][,sockets=sockets]\n" 142 " set the number of CPUs to 'n' [default=1]\n" 143 " maxcpus= maximum number of total cpus, including\n" 144 " offline CPUs for hotplug, etc\n" 145 " cores= number of CPU cores on one socket (for PC, it's on one die)\n" 146 " threads= number of threads on one CPU core\n" 147 " dies= number of CPU dies on one socket (for PC only)\n" 148 " sockets= number of discrete sockets in the system\n", 149 QEMU_ARCH_ALL) 150STEXI 151@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,dies=dies][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 152@findex -smp 153Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 154CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 155to 4. 156For the PC target, the number of @var{cores} per die, the number of @var{threads} 157per cores, the number of @var{dies} per packages and the total number of 158@var{sockets} can be specified. Missing values will be computed. 159If any on the three values is given, the total number of CPUs @var{n} can be omitted. 160@var{maxcpus} specifies the maximum number of hotpluggable CPUs. 161ETEXI 162 163DEF("numa", HAS_ARG, QEMU_OPTION_numa, 164 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 165 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 166 "-numa dist,src=source,dst=destination,val=distance\n" 167 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n", 168 QEMU_ARCH_ALL) 169STEXI 170@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 171@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 172@itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance} 173@itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}] 174@findex -numa 175Define a NUMA node and assign RAM and VCPUs to it. 176Set the NUMA distance from a source node to a destination node. 177 178Legacy VCPU assignment uses @samp{cpus} option where 179@var{firstcpu} and @var{lastcpu} are CPU indexes. Each 180@samp{cpus} option represent a contiguous range of CPU indexes 181(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous 182set of VCPUs can be represented by providing multiple @samp{cpus} 183options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically 184split between them. 185 186For example, the following option assigns VCPUs 0, 1, 2 and 5 to 187a NUMA node: 188@example 189-numa node,cpus=0-2,cpus=5 190@end example 191 192@samp{cpu} option is a new alternative to @samp{cpus} option 193which uses @samp{socket-id|core-id|thread-id} properties to assign 194CPU objects to a @var{node} using topology layout properties of CPU. 195The set of properties is machine specific, and depends on used 196machine type/@samp{smp} options. It could be queried with 197@samp{hotpluggable-cpus} monitor command. 198@samp{node-id} property specifies @var{node} to which CPU object 199will be assigned, it's required for @var{node} to be declared 200with @samp{node} option before it's used with @samp{cpu} option. 201 202For example: 203@example 204-M pc \ 205-smp 1,sockets=2,maxcpus=2 \ 206-numa node,nodeid=0 -numa node,nodeid=1 \ 207-numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1 208@end example 209 210@samp{mem} assigns a given RAM amount to a node. @samp{memdev} 211assigns RAM from a given memory backend device to a node. If 212@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is 213split equally between them. 214 215@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, 216if one node uses @samp{memdev}, all of them have to use it. 217 218@var{source} and @var{destination} are NUMA node IDs. 219@var{distance} is the NUMA distance from @var{source} to @var{destination}. 220The distance from a node to itself is always 10. If any pair of nodes is 221given a distance, then all pairs must be given distances. Although, when 222distances are only given in one direction for each pair of nodes, then 223the distances in the opposite directions are assumed to be the same. If, 224however, an asymmetrical pair of distances is given for even one node 225pair, then all node pairs must be provided distance values for both 226directions, even when they are symmetrical. When a node is unreachable 227from another node, set the pair's distance to 255. 228 229Note that the -@option{numa} option doesn't allocate any of the 230specified resources, it just assigns existing resources to NUMA 231nodes. This means that one still has to use the @option{-m}, 232@option{-smp} options to allocate RAM and VCPUs respectively. 233 234ETEXI 235 236DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 237 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 238 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 239STEXI 240@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 241@findex -add-fd 242 243Add a file descriptor to an fd set. Valid options are: 244 245@table @option 246@item fd=@var{fd} 247This option defines the file descriptor of which a duplicate is added to fd set. 248The file descriptor cannot be stdin, stdout, or stderr. 249@item set=@var{set} 250This option defines the ID of the fd set to add the file descriptor to. 251@item opaque=@var{opaque} 252This option defines a free-form string that can be used to describe @var{fd}. 253@end table 254 255You can open an image using pre-opened file descriptors from an fd set: 256@example 257@value{qemu_system} \ 258 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file" \ 259 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file" \ 260 -drive file=/dev/fdset/2,index=0,media=disk 261@end example 262ETEXI 263 264DEF("set", HAS_ARG, QEMU_OPTION_set, 265 "-set group.id.arg=value\n" 266 " set <arg> parameter for item <id> of type <group>\n" 267 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 268STEXI 269@item -set @var{group}.@var{id}.@var{arg}=@var{value} 270@findex -set 271Set parameter @var{arg} for item @var{id} of type @var{group} 272ETEXI 273 274DEF("global", HAS_ARG, QEMU_OPTION_global, 275 "-global driver.property=value\n" 276 "-global driver=driver,property=property,value=value\n" 277 " set a global default for a driver property\n", 278 QEMU_ARCH_ALL) 279STEXI 280@item -global @var{driver}.@var{prop}=@var{value} 281@itemx -global driver=@var{driver},property=@var{property},value=@var{value} 282@findex -global 283Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 284 285@example 286@value{qemu_system_x86} -global ide-hd.physical_block_size=4096 disk-image.img 287@end example 288 289In particular, you can use this to set driver properties for devices which are 290created automatically by the machine model. To create a device which is not 291created automatically and set properties on it, use -@option{device}. 292 293-global @var{driver}.@var{prop}=@var{value} is shorthand for -global 294driver=@var{driver},property=@var{prop},value=@var{value}. The 295longhand syntax works even when @var{driver} contains a dot. 296ETEXI 297 298DEF("boot", HAS_ARG, QEMU_OPTION_boot, 299 "-boot [order=drives][,once=drives][,menu=on|off]\n" 300 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 301 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 302 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 303 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 304 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 305 QEMU_ARCH_ALL) 306STEXI 307@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] 308@findex -boot 309Specify boot order @var{drives} as a string of drive letters. Valid 310drive letters depend on the target architecture. The x86 PC uses: a, b 311(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 312from network adapter 1-4), hard disk boot is the default. To apply a 313particular boot order only on the first startup, specify it via 314@option{once}. Note that the @option{order} or @option{once} parameter 315should not be used together with the @option{bootindex} property of 316devices, since the firmware implementations normally do not support both 317at the same time. 318 319Interactive boot menus/prompts can be enabled via @option{menu=on} as far 320as firmware/BIOS supports them. The default is non-interactive boot. 321 322A splash picture could be passed to bios, enabling user to show it as logo, 323when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 324supports them. Currently Seabios for X86 system support it. 325limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 326format(true color). The resolution should be supported by the SVGA mode, so 327the recommended is 320x240, 640x480, 800x640. 328 329A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 330when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 331reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 332system support it. 333 334Do strict boot via @option{strict=on} as far as firmware/BIOS 335supports it. This only effects when boot priority is changed by 336bootindex options. The default is non-strict boot. 337 338@example 339# try to boot from network first, then from hard disk 340@value{qemu_system_x86} -boot order=nc 341# boot from CD-ROM first, switch back to default order after reboot 342@value{qemu_system_x86} -boot once=d 343# boot with a splash picture for 5 seconds. 344@value{qemu_system_x86} -boot menu=on,splash=/root/boot.bmp,splash-time=5000 345@end example 346 347Note: The legacy format '-boot @var{drives}' is still supported but its 348use is discouraged as it may be removed from future versions. 349ETEXI 350 351DEF("m", HAS_ARG, QEMU_OPTION_m, 352 "-m [size=]megs[,slots=n,maxmem=size]\n" 353 " configure guest RAM\n" 354 " size: initial amount of guest memory\n" 355 " slots: number of hotplug slots (default: none)\n" 356 " maxmem: maximum amount of guest memory (default: none)\n" 357 "NOTE: Some architectures might enforce a specific granularity\n", 358 QEMU_ARCH_ALL) 359STEXI 360@item -m [size=]@var{megs}[,slots=n,maxmem=size] 361@findex -m 362Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 363Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 364megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 365could be used to set amount of hotpluggable memory slots and maximum amount of 366memory. Note that @var{maxmem} must be aligned to the page size. 367 368For example, the following command-line sets the guest startup RAM size to 3691GB, creates 3 slots to hotplug additional memory and sets the maximum 370memory the guest can reach to 4GB: 371 372@example 373@value{qemu_system} -m 1G,slots=3,maxmem=4G 374@end example 375 376If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 377be enabled and the guest startup RAM will never increase. 378ETEXI 379 380DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 381 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 382STEXI 383@item -mem-path @var{path} 384@findex -mem-path 385Allocate guest RAM from a temporarily created file in @var{path}. 386ETEXI 387 388DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 389 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 390 QEMU_ARCH_ALL) 391STEXI 392@item -mem-prealloc 393@findex -mem-prealloc 394Preallocate memory when using -mem-path. 395ETEXI 396 397DEF("k", HAS_ARG, QEMU_OPTION_k, 398 "-k language use keyboard layout (for example 'fr' for French)\n", 399 QEMU_ARCH_ALL) 400STEXI 401@item -k @var{language} 402@findex -k 403Use keyboard layout @var{language} (for example @code{fr} for 404French). This option is only needed where it is not easy to get raw PC 405keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses 406display). You don't normally need to use it on PC/Linux or PC/Windows 407hosts. 408 409The available layouts are: 410@example 411ar de-ch es fo fr-ca hu ja mk no pt-br sv 412da en-gb et fr fr-ch is lt nl pl ru th 413de en-us fi fr-be hr it lv nl-be pt sl tr 414@end example 415 416The default is @code{en-us}. 417ETEXI 418 419 420HXCOMM Deprecated by -audiodev 421DEF("audio-help", 0, QEMU_OPTION_audio_help, 422 "-audio-help show -audiodev equivalent of the currently specified audio settings\n", 423 QEMU_ARCH_ALL) 424STEXI 425@item -audio-help 426@findex -audio-help 427Will show the -audiodev equivalent of the currently specified 428(deprecated) environment variables. 429ETEXI 430 431DEF("audiodev", HAS_ARG, QEMU_OPTION_audiodev, 432 "-audiodev [driver=]driver,id=id[,prop[=value][,...]]\n" 433 " specifies the audio backend to use\n" 434 " id= identifier of the backend\n" 435 " timer-period= timer period in microseconds\n" 436 " in|out.mixing-engine= use mixing engine to mix streams inside QEMU\n" 437 " in|out.fixed-settings= use fixed settings for host audio\n" 438 " in|out.frequency= frequency to use with fixed settings\n" 439 " in|out.channels= number of channels to use with fixed settings\n" 440 " in|out.format= sample format to use with fixed settings\n" 441 " valid values: s8, s16, s32, u8, u16, u32\n" 442 " in|out.voices= number of voices to use\n" 443 " in|out.buffer-length= length of buffer in microseconds\n" 444 "-audiodev none,id=id,[,prop[=value][,...]]\n" 445 " dummy driver that discards all output\n" 446#ifdef CONFIG_AUDIO_ALSA 447 "-audiodev alsa,id=id[,prop[=value][,...]]\n" 448 " in|out.dev= name of the audio device to use\n" 449 " in|out.period-length= length of period in microseconds\n" 450 " in|out.try-poll= attempt to use poll mode\n" 451 " threshold= threshold (in microseconds) when playback starts\n" 452#endif 453#ifdef CONFIG_AUDIO_COREAUDIO 454 "-audiodev coreaudio,id=id[,prop[=value][,...]]\n" 455 " in|out.buffer-count= number of buffers\n" 456#endif 457#ifdef CONFIG_AUDIO_DSOUND 458 "-audiodev dsound,id=id[,prop[=value][,...]]\n" 459 " latency= add extra latency to playback in microseconds\n" 460#endif 461#ifdef CONFIG_AUDIO_OSS 462 "-audiodev oss,id=id[,prop[=value][,...]]\n" 463 " in|out.dev= path of the audio device to use\n" 464 " in|out.buffer-count= number of buffers\n" 465 " in|out.try-poll= attempt to use poll mode\n" 466 " try-mmap= try using memory mapped access\n" 467 " exclusive= open device in exclusive mode\n" 468 " dsp-policy= set timing policy (0..10), -1 to use fragment mode\n" 469#endif 470#ifdef CONFIG_AUDIO_PA 471 "-audiodev pa,id=id[,prop[=value][,...]]\n" 472 " server= PulseAudio server address\n" 473 " in|out.name= source/sink device name\n" 474#endif 475#ifdef CONFIG_AUDIO_SDL 476 "-audiodev sdl,id=id[,prop[=value][,...]]\n" 477#endif 478#ifdef CONFIG_SPICE 479 "-audiodev spice,id=id[,prop[=value][,...]]\n" 480#endif 481 "-audiodev wav,id=id[,prop[=value][,...]]\n" 482 " path= path of wav file to record\n", 483 QEMU_ARCH_ALL) 484STEXI 485@item -audiodev [driver=]@var{driver},id=@var{id}[,@var{prop}[=@var{value}][,...]] 486@findex -audiodev 487Adds a new audio backend @var{driver} identified by @var{id}. There are 488global and driver specific properties. Some values can be set 489differently for input and output, they're marked with @code{in|out.}. 490You can set the input's property with @code{in.@var{prop}} and the 491output's property with @code{out.@var{prop}}. For example: 492@example 493-audiodev alsa,id=example,in.frequency=44110,out.frequency=8000 494-audiodev alsa,id=example,out.channels=1 # leaves in.channels unspecified 495@end example 496 497NOTE: parameter validation is known to be incomplete, in many cases 498specifying an invalid option causes QEMU to print an error message and 499continue emulation without sound. 500 501Valid global options are: 502 503@table @option 504@item id=@var{identifier} 505Identifies the audio backend. 506 507@item timer-period=@var{period} 508Sets the timer @var{period} used by the audio subsystem in microseconds. 509Default is 10000 (10 ms). 510 511@item in|out.mixing-engine=on|off 512Use QEMU's mixing engine to mix all streams inside QEMU and convert 513audio formats when not supported by the backend. When off, 514@var{fixed-settings} must be off too. Note that disabling this option 515means that the selected backend must support multiple streams and the 516audio formats used by the virtual cards, otherwise you'll get no sound. 517It's not recommended to disable this option unless you want to use 5.1 518or 7.1 audio, as mixing engine only supports mono and stereo audio. 519Default is on. 520 521@item in|out.fixed-settings=on|off 522Use fixed settings for host audio. When off, it will change based on 523how the guest opens the sound card. In this case you must not specify 524@var{frequency}, @var{channels} or @var{format}. Default is on. 525 526@item in|out.frequency=@var{frequency} 527Specify the @var{frequency} to use when using @var{fixed-settings}. 528Default is 44100Hz. 529 530@item in|out.channels=@var{channels} 531Specify the number of @var{channels} to use when using 532@var{fixed-settings}. Default is 2 (stereo). 533 534@item in|out.format=@var{format} 535Specify the sample @var{format} to use when using @var{fixed-settings}. 536Valid values are: @code{s8}, @code{s16}, @code{s32}, @code{u8}, 537@code{u16}, @code{u32}. Default is @code{s16}. 538 539@item in|out.voices=@var{voices} 540Specify the number of @var{voices} to use. Default is 1. 541 542@item in|out.buffer-length=@var{usecs} 543Sets the size of the buffer in microseconds. 544 545@end table 546 547@item -audiodev none,id=@var{id}[,@var{prop}[=@var{value}][,...]] 548Creates a dummy backend that discards all outputs. This backend has no 549backend specific properties. 550 551@item -audiodev alsa,id=@var{id}[,@var{prop}[=@var{value}][,...]] 552Creates backend using the ALSA. This backend is only available on 553Linux. 554 555ALSA specific options are: 556 557@table @option 558 559@item in|out.dev=@var{device} 560Specify the ALSA @var{device} to use for input and/or output. Default 561is @code{default}. 562 563@item in|out.period-length=@var{usecs} 564Sets the period length in microseconds. 565 566@item in|out.try-poll=on|off 567Attempt to use poll mode with the device. Default is on. 568 569@item threshold=@var{threshold} 570Threshold (in microseconds) when playback starts. Default is 0. 571 572@end table 573 574@item -audiodev coreaudio,id=@var{id}[,@var{prop}[=@var{value}][,...]] 575Creates a backend using Apple's Core Audio. This backend is only 576available on Mac OS and only supports playback. 577 578Core Audio specific options are: 579 580@table @option 581 582@item in|out.buffer-count=@var{count} 583Sets the @var{count} of the buffers. 584 585@end table 586 587@item -audiodev dsound,id=@var{id}[,@var{prop}[=@var{value}][,...]] 588Creates a backend using Microsoft's DirectSound. This backend is only 589available on Windows and only supports playback. 590 591DirectSound specific options are: 592 593@table @option 594 595@item latency=@var{usecs} 596Add extra @var{usecs} microseconds latency to playback. Default is 59710000 (10 ms). 598 599@end table 600 601@item -audiodev oss,id=@var{id}[,@var{prop}[=@var{value}][,...]] 602Creates a backend using OSS. This backend is available on most 603Unix-like systems. 604 605OSS specific options are: 606 607@table @option 608 609@item in|out.dev=@var{device} 610Specify the file name of the OSS @var{device} to use. Default is 611@code{/dev/dsp}. 612 613@item in|out.buffer-count=@var{count} 614Sets the @var{count} of the buffers. 615 616@item in|out.try-poll=on|of 617Attempt to use poll mode with the device. Default is on. 618 619@item try-mmap=on|off 620Try using memory mapped device access. Default is off. 621 622@item exclusive=on|off 623Open the device in exclusive mode (vmix won't work in this case). 624Default is off. 625 626@item dsp-policy=@var{policy} 627Sets the timing policy (between 0 and 10, where smaller number means 628smaller latency but higher CPU usage). Use -1 to use buffer sizes 629specified by @code{buffer} and @code{buffer-count}. This option is 630ignored if you do not have OSS 4. Default is 5. 631 632@end table 633 634@item -audiodev pa,id=@var{id}[,@var{prop}[=@var{value}][,...]] 635Creates a backend using PulseAudio. This backend is available on most 636systems. 637 638PulseAudio specific options are: 639 640@table @option 641 642@item server=@var{server} 643Sets the PulseAudio @var{server} to connect to. 644 645@item in|out.name=@var{sink} 646Use the specified source/sink for recording/playback. 647 648@end table 649 650@item -audiodev sdl,id=@var{id}[,@var{prop}[=@var{value}][,...]] 651Creates a backend using SDL. This backend is available on most systems, 652but you should use your platform's native backend if possible. This 653backend has no backend specific properties. 654 655@item -audiodev spice,id=@var{id}[,@var{prop}[=@var{value}][,...]] 656Creates a backend that sends audio through SPICE. This backend requires 657@code{-spice} and automatically selected in that case, so usually you 658can ignore this option. This backend has no backend specific 659properties. 660 661@item -audiodev wav,id=@var{id}[,@var{prop}[=@var{value}][,...]] 662Creates a backend that writes audio to a WAV file. 663 664Backend specific options are: 665 666@table @option 667 668@item path=@var{path} 669Write recorded audio into the specified file. Default is 670@code{qemu.wav}. 671 672@end table 673ETEXI 674 675DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 676 "-soundhw c1,... enable audio support\n" 677 " and only specified sound cards (comma separated list)\n" 678 " use '-soundhw help' to get the list of supported cards\n" 679 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 680STEXI 681@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 682@findex -soundhw 683Enable audio and selected sound hardware. Use 'help' to print all 684available sound hardware. For example: 685 686@example 687@value{qemu_system_x86} -soundhw sb16,adlib disk.img 688@value{qemu_system_x86} -soundhw es1370 disk.img 689@value{qemu_system_x86} -soundhw ac97 disk.img 690@value{qemu_system_x86} -soundhw hda disk.img 691@value{qemu_system_x86} -soundhw all disk.img 692@value{qemu_system_x86} -soundhw help 693@end example 694 695Note that Linux's i810_audio OSS kernel (for AC97) module might 696require manually specifying clocking. 697 698@example 699modprobe i810_audio clocking=48000 700@end example 701ETEXI 702 703DEF("device", HAS_ARG, QEMU_OPTION_device, 704 "-device driver[,prop[=value][,...]]\n" 705 " add device (based on driver)\n" 706 " prop=value,... sets driver properties\n" 707 " use '-device help' to print all possible drivers\n" 708 " use '-device driver,help' to print all possible properties\n", 709 QEMU_ARCH_ALL) 710STEXI 711@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 712@findex -device 713Add device @var{driver}. @var{prop}=@var{value} sets driver 714properties. Valid properties depend on the driver. To get help on 715possible drivers and properties, use @code{-device help} and 716@code{-device @var{driver},help}. 717 718Some drivers are: 719@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}][,guid=@var{uuid}] 720 721Add an IPMI BMC. This is a simulation of a hardware management 722interface processor that normally sits on a system. It provides 723a watchdog and the ability to reset and power control the system. 724You need to connect this to an IPMI interface to make it useful 725 726The IPMI slave address to use for the BMC. The default is 0x20. 727This address is the BMC's address on the I2C network of management 728controllers. If you don't know what this means, it is safe to ignore 729it. 730 731@table @option 732@item id=@var{id} 733The BMC id for interfaces to use this device. 734@item slave_addr=@var{val} 735Define slave address to use for the BMC. The default is 0x20. 736@item sdrfile=@var{file} 737file containing raw Sensor Data Records (SDR) data. The default is none. 738@item fruareasize=@var{val} 739size of a Field Replaceable Unit (FRU) area. The default is 1024. 740@item frudatafile=@var{file} 741file containing raw Field Replaceable Unit (FRU) inventory data. The default is none. 742@item guid=@var{uuid} 743value for the GUID for the BMC, in standard UUID format. If this is set, 744get "Get GUID" command to the BMC will return it. Otherwise "Get GUID" 745will return an error. 746@end table 747 748@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 749 750Add a connection to an external IPMI BMC simulator. Instead of 751locally emulating the BMC like the above item, instead connect 752to an external entity that provides the IPMI services. 753 754A connection is made to an external BMC simulator. If you do this, it 755is strongly recommended that you use the "reconnect=" chardev option 756to reconnect to the simulator if the connection is lost. Note that if 757this is not used carefully, it can be a security issue, as the 758interface has the ability to send resets, NMIs, and power off the VM. 759It's best if QEMU makes a connection to an external simulator running 760on a secure port on localhost, so neither the simulator nor QEMU is 761exposed to any outside network. 762 763See the "lanserv/README.vm" file in the OpenIPMI library for more 764details on the external interface. 765 766@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 767 768Add a KCS IPMI interafce on the ISA bus. This also adds a 769corresponding ACPI and SMBIOS entries, if appropriate. 770 771@table @option 772@item bmc=@var{id} 773The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 774@item ioport=@var{val} 775Define the I/O address of the interface. The default is 0xca0 for KCS. 776@item irq=@var{val} 777Define the interrupt to use. The default is 5. To disable interrupts, 778set this to 0. 779@end table 780 781@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 782 783Like the KCS interface, but defines a BT interface. The default port is 7840xe4 and the default interrupt is 5. 785 786ETEXI 787 788DEF("name", HAS_ARG, QEMU_OPTION_name, 789 "-name string1[,process=string2][,debug-threads=on|off]\n" 790 " set the name of the guest\n" 791 " string1 sets the window title and string2 the process name\n" 792 " When debug-threads is enabled, individual threads are given a separate name\n" 793 " NOTE: The thread names are for debugging and not a stable API.\n", 794 QEMU_ARCH_ALL) 795STEXI 796@item -name @var{name} 797@findex -name 798Sets the @var{name} of the guest. 799This name will be displayed in the SDL window caption. 800The @var{name} will also be used for the VNC server. 801Also optionally set the top visible process name in Linux. 802Naming of individual threads can also be enabled on Linux to aid debugging. 803ETEXI 804 805DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 806 "-uuid %08x-%04x-%04x-%04x-%012x\n" 807 " specify machine UUID\n", QEMU_ARCH_ALL) 808STEXI 809@item -uuid @var{uuid} 810@findex -uuid 811Set system UUID. 812ETEXI 813 814STEXI 815@end table 816ETEXI 817DEFHEADING() 818 819DEFHEADING(Block device options:) 820STEXI 821@table @option 822ETEXI 823 824DEF("fda", HAS_ARG, QEMU_OPTION_fda, 825 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 826DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 827STEXI 828@item -fda @var{file} 829@itemx -fdb @var{file} 830@findex -fda 831@findex -fdb 832Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 833ETEXI 834 835DEF("hda", HAS_ARG, QEMU_OPTION_hda, 836 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 837DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 838DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 839 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 840DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 841STEXI 842@item -hda @var{file} 843@itemx -hdb @var{file} 844@itemx -hdc @var{file} 845@itemx -hdd @var{file} 846@findex -hda 847@findex -hdb 848@findex -hdc 849@findex -hdd 850Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 851ETEXI 852 853DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 854 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 855 QEMU_ARCH_ALL) 856STEXI 857@item -cdrom @var{file} 858@findex -cdrom 859Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 860@option{-cdrom} at the same time). You can use the host CD-ROM by 861using @file{/dev/cdrom} as filename (@pxref{host_drives}). 862ETEXI 863 864DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev, 865 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n" 866 " [,cache.direct=on|off][,cache.no-flush=on|off]\n" 867 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n" 868 " [,driver specific parameters...]\n" 869 " configure a block backend\n", QEMU_ARCH_ALL) 870STEXI 871@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]] 872@findex -blockdev 873 874Define a new block driver node. Some of the options apply to all block drivers, 875other options are only accepted for a specific block driver. See below for a 876list of generic options and options for the most common block drivers. 877 878Options that expect a reference to another node (e.g. @code{file}) can be 879given in two ways. Either you specify the node name of an already existing node 880(file=@var{node-name}), or you define a new node inline, adding options 881for the referenced node after a dot (file.filename=@var{path},file.aio=native). 882 883A block driver node created with @option{-blockdev} can be used for a guest 884device by specifying its node name for the @code{drive} property in a 885@option{-device} argument that defines a block device. 886 887@table @option 888@item Valid options for any block driver node: 889 890@table @code 891@item driver 892Specifies the block driver to use for the given node. 893@item node-name 894This defines the name of the block driver node by which it will be referenced 895later. The name must be unique, i.e. it must not match the name of a different 896block driver node, or (if you use @option{-drive} as well) the ID of a drive. 897 898If no node name is specified, it is automatically generated. The generated node 899name is not intended to be predictable and changes between QEMU invocations. 900For the top level, an explicit node name must be specified. 901@item read-only 902Open the node read-only. Guest write attempts will fail. 903@item cache.direct 904The host page cache can be avoided with @option{cache.direct=on}. This will 905attempt to do disk IO directly to the guest's memory. QEMU may still perform an 906internal copy of the data. 907@item cache.no-flush 908In case you don't care about data integrity over host failures, you can use 909@option{cache.no-flush=on}. This option tells QEMU that it never needs to write 910any data to the disk but can instead keep things in cache. If anything goes 911wrong, like your host losing power, the disk storage getting disconnected 912accidentally, etc. your image will most probably be rendered unusable. 913@item discard=@var{discard} 914@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls 915whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are 916ignored or passed to the filesystem. Some machine types may not support 917discard requests. 918@item detect-zeroes=@var{detect-zeroes} 919@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 920conversion of plain zero writes by the OS to driver specific optimized 921zero write commands. You may even choose "unmap" if @var{discard} is set 922to "unmap" to allow a zero write to be converted to an @code{unmap} operation. 923@end table 924 925@item Driver-specific options for @code{file} 926 927This is the protocol-level block driver for accessing regular files. 928 929@table @code 930@item filename 931The path to the image file in the local filesystem 932@item aio 933Specifies the AIO backend (threads/native, default: threads) 934@item locking 935Specifies whether the image file is protected with Linux OFD / POSIX locks. The 936default is to use the Linux Open File Descriptor API if available, otherwise no 937lock is applied. (auto/on/off, default: auto) 938@end table 939Example: 940@example 941-blockdev driver=file,node-name=disk,filename=disk.img 942@end example 943 944@item Driver-specific options for @code{raw} 945 946This is the image format block driver for raw images. It is usually 947stacked on top of a protocol level block driver such as @code{file}. 948 949@table @code 950@item file 951Reference to or definition of the data source block driver node 952(e.g. a @code{file} driver node) 953@end table 954Example 1: 955@example 956-blockdev driver=file,node-name=disk_file,filename=disk.img 957-blockdev driver=raw,node-name=disk,file=disk_file 958@end example 959Example 2: 960@example 961-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img 962@end example 963 964@item Driver-specific options for @code{qcow2} 965 966This is the image format block driver for qcow2 images. It is usually 967stacked on top of a protocol level block driver such as @code{file}. 968 969@table @code 970@item file 971Reference to or definition of the data source block driver node 972(e.g. a @code{file} driver node) 973 974@item backing 975Reference to or definition of the backing file block device (default is taken 976from the image file). It is allowed to pass @code{null} here in order to disable 977the default backing file. 978 979@item lazy-refcounts 980Whether to enable the lazy refcounts feature (on/off; default is taken from the 981image file) 982 983@item cache-size 984The maximum total size of the L2 table and refcount block caches in bytes 985(default: the sum of l2-cache-size and refcount-cache-size) 986 987@item l2-cache-size 988The maximum size of the L2 table cache in bytes 989(default: if cache-size is not specified - 32M on Linux platforms, and 8M on 990non-Linux platforms; otherwise, as large as possible within the cache-size, 991while permitting the requested or the minimal refcount cache size) 992 993@item refcount-cache-size 994The maximum size of the refcount block cache in bytes 995(default: 4 times the cluster size; or if cache-size is specified, the part of 996it which is not used for the L2 cache) 997 998@item cache-clean-interval 999Clean unused entries in the L2 and refcount caches. The interval is in seconds. 1000The default value is 600 on supporting platforms, and 0 on other platforms. 1001Setting it to 0 disables this feature. 1002 1003@item pass-discard-request 1004Whether discard requests to the qcow2 device should be forwarded to the data 1005source (on/off; default: on if discard=unmap is specified, off otherwise) 1006 1007@item pass-discard-snapshot 1008Whether discard requests for the data source should be issued when a snapshot 1009operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off; 1010default: on) 1011 1012@item pass-discard-other 1013Whether discard requests for the data source should be issued on other 1014occasions where a cluster gets freed (on/off; default: off) 1015 1016@item overlap-check 1017Which overlap checks to perform for writes to the image 1018(none/constant/cached/all; default: cached). For details or finer 1019granularity control refer to the QAPI documentation of @code{blockdev-add}. 1020@end table 1021 1022Example 1: 1023@example 1024-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2 1025-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216 1026@end example 1027Example 2: 1028@example 1029-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2 1030@end example 1031 1032@item Driver-specific options for other drivers 1033Please refer to the QAPI documentation of the @code{blockdev-add} QMP command. 1034 1035@end table 1036 1037ETEXI 1038 1039DEF("drive", HAS_ARG, QEMU_OPTION_drive, 1040 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 1041 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 1042 " [,snapshot=on|off][,rerror=ignore|stop|report]\n" 1043 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 1044 " [,readonly=on|off][,copy-on-read=on|off]\n" 1045 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 1046 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 1047 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 1048 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 1049 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 1050 " [[,iops_size=is]]\n" 1051 " [[,group=g]]\n" 1052 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 1053STEXI 1054@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 1055@findex -drive 1056 1057Define a new drive. This includes creating a block driver node (the backend) as 1058well as a guest device, and is mostly a shortcut for defining the corresponding 1059@option{-blockdev} and @option{-device} options. 1060 1061@option{-drive} accepts all options that are accepted by @option{-blockdev}. In 1062addition, it knows the following options: 1063 1064@table @option 1065@item file=@var{file} 1066This option defines which disk image (@pxref{disk_images}) to use with 1067this drive. If the filename contains comma, you must double it 1068(for instance, "file=my,,file" to use file "my,file"). 1069 1070Special files such as iSCSI devices can be specified using protocol 1071specific URLs. See the section for "Device URL Syntax" for more information. 1072@item if=@var{interface} 1073This option defines on which type on interface the drive is connected. 1074Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none. 1075@item bus=@var{bus},unit=@var{unit} 1076These options define where is connected the drive by defining the bus number and 1077the unit id. 1078@item index=@var{index} 1079This option defines where is connected the drive by using an index in the list 1080of available connectors of a given interface type. 1081@item media=@var{media} 1082This option defines the type of the media: disk or cdrom. 1083@item snapshot=@var{snapshot} 1084@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 1085(see @option{-snapshot}). 1086@item cache=@var{cache} 1087@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" 1088and controls how the host cache is used to access block data. This is a 1089shortcut that sets the @option{cache.direct} and @option{cache.no-flush} 1090options (as in @option{-blockdev}), and additionally @option{cache.writeback}, 1091which provides a default for the @option{write-cache} option of block guest 1092devices (as in @option{-device}). The modes correspond to the following 1093settings: 1094 1095@c Our texi2pod.pl script doesn't support @multitable, so fall back to using 1096@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage 1097@c and the HTML output. 1098@example 1099@ │ cache.writeback cache.direct cache.no-flush 1100─────────────┼───────────────────────────────────────────────── 1101writeback │ on off off 1102none │ on on off 1103writethrough │ off off off 1104directsync │ off on off 1105unsafe │ on off on 1106@end example 1107 1108The default mode is @option{cache=writeback}. 1109 1110@item aio=@var{aio} 1111@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 1112@item format=@var{format} 1113Specify which disk @var{format} will be used rather than detecting 1114the format. Can be used to specify format=raw to avoid interpreting 1115an untrusted format header. 1116@item werror=@var{action},rerror=@var{action} 1117Specify which @var{action} to take on write and read errors. Valid actions are: 1118"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 1119"report" (report the error to the guest), "enospc" (pause QEMU only if the 1120host disk is full; report the error to the guest otherwise). 1121The default setting is @option{werror=enospc} and @option{rerror=report}. 1122@item copy-on-read=@var{copy-on-read} 1123@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 1124file sectors into the image file. 1125@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w} 1126Specify bandwidth throttling limits in bytes per second, either for all request 1127types or for reads or writes only. Small values can lead to timeouts or hangs 1128inside the guest. A safe minimum for disks is 2 MB/s. 1129@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm} 1130Specify bursts in bytes per second, either for all request types or for reads 1131or writes only. Bursts allow the guest I/O to spike above the limit 1132temporarily. 1133@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w} 1134Specify request rate limits in requests per second, either for all request 1135types or for reads or writes only. 1136@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm} 1137Specify bursts in requests per second, either for all request types or for reads 1138or writes only. Bursts allow the guest I/O to spike above the limit 1139temporarily. 1140@item iops_size=@var{is} 1141Let every @var{is} bytes of a request count as a new request for iops 1142throttling purposes. Use this option to prevent guests from circumventing iops 1143limits by sending fewer but larger requests. 1144@item group=@var{g} 1145Join a throttling quota group with given name @var{g}. All drives that are 1146members of the same group are accounted for together. Use this option to 1147prevent guests from circumventing throttling limits by using many small disks 1148instead of a single larger disk. 1149@end table 1150 1151By default, the @option{cache.writeback=on} mode is used. It will report data 1152writes as completed as soon as the data is present in the host page cache. 1153This is safe as long as your guest OS makes sure to correctly flush disk caches 1154where needed. If your guest OS does not handle volatile disk write caches 1155correctly and your host crashes or loses power, then the guest may experience 1156data corruption. 1157 1158For such guests, you should consider using @option{cache.writeback=off}. This 1159means that the host page cache will be used to read and write data, but write 1160notification will be sent to the guest only after QEMU has made sure to flush 1161each write to the disk. Be aware that this has a major impact on performance. 1162 1163When using the @option{-snapshot} option, unsafe caching is always used. 1164 1165Copy-on-read avoids accessing the same backing file sectors repeatedly and is 1166useful when the backing file is over a slow network. By default copy-on-read 1167is off. 1168 1169Instead of @option{-cdrom} you can use: 1170@example 1171@value{qemu_system} -drive file=file,index=2,media=cdrom 1172@end example 1173 1174Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 1175use: 1176@example 1177@value{qemu_system} -drive file=file,index=0,media=disk 1178@value{qemu_system} -drive file=file,index=1,media=disk 1179@value{qemu_system} -drive file=file,index=2,media=disk 1180@value{qemu_system} -drive file=file,index=3,media=disk 1181@end example 1182 1183You can open an image using pre-opened file descriptors from an fd set: 1184@example 1185@value{qemu_system} \ 1186 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file" \ 1187 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file" \ 1188 -drive file=/dev/fdset/2,index=0,media=disk 1189@end example 1190 1191You can connect a CDROM to the slave of ide0: 1192@example 1193@value{qemu_system_x86} -drive file=file,if=ide,index=1,media=cdrom 1194@end example 1195 1196If you don't specify the "file=" argument, you define an empty drive: 1197@example 1198@value{qemu_system_x86} -drive if=ide,index=1,media=cdrom 1199@end example 1200 1201Instead of @option{-fda}, @option{-fdb}, you can use: 1202@example 1203@value{qemu_system_x86} -drive file=file,index=0,if=floppy 1204@value{qemu_system_x86} -drive file=file,index=1,if=floppy 1205@end example 1206 1207By default, @var{interface} is "ide" and @var{index} is automatically 1208incremented: 1209@example 1210@value{qemu_system_x86} -drive file=a -drive file=b" 1211@end example 1212is interpreted like: 1213@example 1214@value{qemu_system_x86} -hda a -hdb b 1215@end example 1216ETEXI 1217 1218DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 1219 "-mtdblock file use 'file' as on-board Flash memory image\n", 1220 QEMU_ARCH_ALL) 1221STEXI 1222@item -mtdblock @var{file} 1223@findex -mtdblock 1224Use @var{file} as on-board Flash memory image. 1225ETEXI 1226 1227DEF("sd", HAS_ARG, QEMU_OPTION_sd, 1228 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 1229STEXI 1230@item -sd @var{file} 1231@findex -sd 1232Use @var{file} as SecureDigital card image. 1233ETEXI 1234 1235DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 1236 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 1237STEXI 1238@item -pflash @var{file} 1239@findex -pflash 1240Use @var{file} as a parallel flash image. 1241ETEXI 1242 1243DEF("snapshot", 0, QEMU_OPTION_snapshot, 1244 "-snapshot write to temporary files instead of disk image files\n", 1245 QEMU_ARCH_ALL) 1246STEXI 1247@item -snapshot 1248@findex -snapshot 1249Write to temporary files instead of disk image files. In this case, 1250the raw disk image you use is not written back. You can however force 1251the write back by pressing @key{C-a s} (@pxref{disk_images}). 1252ETEXI 1253 1254DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 1255 "-fsdev local,id=id,path=path,security_model=mapped-xattr|mapped-file|passthrough|none\n" 1256 " [,writeout=immediate][,readonly][,fmode=fmode][,dmode=dmode]\n" 1257 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n" 1258 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n" 1259 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n" 1260 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n" 1261 " [[,throttling.iops-size=is]]\n" 1262 "-fsdev proxy,id=id,socket=socket[,writeout=immediate][,readonly]\n" 1263 "-fsdev proxy,id=id,sock_fd=sock_fd[,writeout=immediate][,readonly]\n" 1264 "-fsdev synth,id=id\n", 1265 QEMU_ARCH_ALL) 1266 1267STEXI 1268 1269@item -fsdev local,id=@var{id},path=@var{path},security_model=@var{security_model} [,writeout=@var{writeout}][,readonly][,fmode=@var{fmode}][,dmode=@var{dmode}] [,throttling.@var{option}=@var{value}[,throttling.@var{option}=@var{value}[,...]]] 1270@itemx -fsdev proxy,id=@var{id},socket=@var{socket}[,writeout=@var{writeout}][,readonly] 1271@itemx -fsdev proxy,id=@var{id},sock_fd=@var{sock_fd}[,writeout=@var{writeout}][,readonly] 1272@itemx -fsdev synth,id=@var{id}[,readonly] 1273@findex -fsdev 1274Define a new file system device. Valid options are: 1275@table @option 1276@item local 1277Accesses to the filesystem are done by QEMU. 1278@item proxy 1279Accesses to the filesystem are done by virtfs-proxy-helper(1). 1280@item synth 1281Synthetic filesystem, only used by QTests. 1282@item id=@var{id} 1283Specifies identifier for this device. 1284@item path=@var{path} 1285Specifies the export path for the file system device. Files under 1286this path will be available to the 9p client on the guest. 1287@item security_model=@var{security_model} 1288Specifies the security model to be used for this export path. 1289Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1290In "passthrough" security model, files are stored using the same 1291credentials as they are created on the guest. This requires QEMU 1292to run as root. In "mapped-xattr" security model, some of the file 1293attributes like uid, gid, mode bits and link target are stored as 1294file attributes. For "mapped-file" these attributes are stored in the 1295hidden .virtfs_metadata directory. Directories exported by this security model cannot 1296interact with other unix tools. "none" security model is same as 1297passthrough except the sever won't report failures if it fails to 1298set file attributes like ownership. Security model is mandatory 1299only for local fsdriver. Other fsdrivers (like proxy) don't take 1300security model as a parameter. 1301@item writeout=@var{writeout} 1302This is an optional argument. The only supported value is "immediate". 1303This means that host page cache will be used to read and write data but 1304write notification will be sent to the guest only when the data has been 1305reported as written by the storage subsystem. 1306@item readonly 1307Enables exporting 9p share as a readonly mount for guests. By default 1308read-write access is given. 1309@item socket=@var{socket} 1310Enables proxy filesystem driver to use passed socket file for communicating 1311with virtfs-proxy-helper(1). 1312@item sock_fd=@var{sock_fd} 1313Enables proxy filesystem driver to use passed socket descriptor for 1314communicating with virtfs-proxy-helper(1). Usually a helper like libvirt 1315will create socketpair and pass one of the fds as sock_fd. 1316@item fmode=@var{fmode} 1317Specifies the default mode for newly created files on the host. Works only 1318with security models "mapped-xattr" and "mapped-file". 1319@item dmode=@var{dmode} 1320Specifies the default mode for newly created directories on the host. Works 1321only with security models "mapped-xattr" and "mapped-file". 1322@item throttling.bps-total=@var{b},throttling.bps-read=@var{r},throttling.bps-write=@var{w} 1323Specify bandwidth throttling limits in bytes per second, either for all request 1324types or for reads or writes only. 1325@item throttling.bps-total-max=@var{bm},bps-read-max=@var{rm},bps-write-max=@var{wm} 1326Specify bursts in bytes per second, either for all request types or for reads 1327or writes only. Bursts allow the guest I/O to spike above the limit 1328temporarily. 1329@item throttling.iops-total=@var{i},throttling.iops-read=@var{r}, throttling.iops-write=@var{w} 1330Specify request rate limits in requests per second, either for all request 1331types or for reads or writes only. 1332@item throttling.iops-total-max=@var{im},throttling.iops-read-max=@var{irm}, throttling.iops-write-max=@var{iwm} 1333Specify bursts in requests per second, either for all request types or for reads 1334or writes only. Bursts allow the guest I/O to spike above the limit temporarily. 1335@item throttling.iops-size=@var{is} 1336Let every @var{is} bytes of a request count as a new request for iops 1337throttling purposes. 1338@end table 1339 1340-fsdev option is used along with -device driver "virtio-9p-...". 1341@item -device virtio-9p-@var{type},fsdev=@var{id},mount_tag=@var{mount_tag} 1342Options for virtio-9p-... driver are: 1343@table @option 1344@item @var{type} 1345Specifies the variant to be used. Supported values are "pci", "ccw" or "device", 1346depending on the machine type. 1347@item fsdev=@var{id} 1348Specifies the id value specified along with -fsdev option. 1349@item mount_tag=@var{mount_tag} 1350Specifies the tag name to be used by the guest to mount this export point. 1351@end table 1352 1353ETEXI 1354 1355DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 1356 "-virtfs local,path=path,mount_tag=tag,security_model=mapped-xattr|mapped-file|passthrough|none\n" 1357 " [,id=id][,writeout=immediate][,readonly][,fmode=fmode][,dmode=dmode][,multidevs=remap|forbid|warn]\n" 1358 "-virtfs proxy,mount_tag=tag,socket=socket[,id=id][,writeout=immediate][,readonly]\n" 1359 "-virtfs proxy,mount_tag=tag,sock_fd=sock_fd[,id=id][,writeout=immediate][,readonly]\n" 1360 "-virtfs synth,mount_tag=tag[,id=id][,readonly]\n", 1361 QEMU_ARCH_ALL) 1362 1363STEXI 1364 1365@item -virtfs local,path=@var{path},mount_tag=@var{mount_tag} ,security_model=@var{security_model}[,writeout=@var{writeout}][,readonly] [,fmode=@var{fmode}][,dmode=@var{dmode}][,multidevs=@var{multidevs}] 1366@itemx -virtfs proxy,socket=@var{socket},mount_tag=@var{mount_tag} [,writeout=@var{writeout}][,readonly] 1367@itemx -virtfs proxy,sock_fd=@var{sock_fd},mount_tag=@var{mount_tag} [,writeout=@var{writeout}][,readonly] 1368@itemx -virtfs synth,mount_tag=@var{mount_tag} 1369@findex -virtfs 1370 1371Define a new filesystem device and expose it to the guest using a virtio-9p-device. The general form of a Virtual File system pass-through options are: 1372@table @option 1373@item local 1374Accesses to the filesystem are done by QEMU. 1375@item proxy 1376Accesses to the filesystem are done by virtfs-proxy-helper(1). 1377@item synth 1378Synthetic filesystem, only used by QTests. 1379@item id=@var{id} 1380Specifies identifier for the filesystem device 1381@item path=@var{path} 1382Specifies the export path for the file system device. Files under 1383this path will be available to the 9p client on the guest. 1384@item security_model=@var{security_model} 1385Specifies the security model to be used for this export path. 1386Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1387In "passthrough" security model, files are stored using the same 1388credentials as they are created on the guest. This requires QEMU 1389to run as root. In "mapped-xattr" security model, some of the file 1390attributes like uid, gid, mode bits and link target are stored as 1391file attributes. For "mapped-file" these attributes are stored in the 1392hidden .virtfs_metadata directory. Directories exported by this security model cannot 1393interact with other unix tools. "none" security model is same as 1394passthrough except the sever won't report failures if it fails to 1395set file attributes like ownership. Security model is mandatory only 1396for local fsdriver. Other fsdrivers (like proxy) don't take security 1397model as a parameter. 1398@item writeout=@var{writeout} 1399This is an optional argument. The only supported value is "immediate". 1400This means that host page cache will be used to read and write data but 1401write notification will be sent to the guest only when the data has been 1402reported as written by the storage subsystem. 1403@item readonly 1404Enables exporting 9p share as a readonly mount for guests. By default 1405read-write access is given. 1406@item socket=@var{socket} 1407Enables proxy filesystem driver to use passed socket file for 1408communicating with virtfs-proxy-helper(1). Usually a helper like libvirt 1409will create socketpair and pass one of the fds as sock_fd. 1410@item sock_fd 1411Enables proxy filesystem driver to use passed 'sock_fd' as the socket 1412descriptor for interfacing with virtfs-proxy-helper(1). 1413@item fmode=@var{fmode} 1414Specifies the default mode for newly created files on the host. Works only 1415with security models "mapped-xattr" and "mapped-file". 1416@item dmode=@var{dmode} 1417Specifies the default mode for newly created directories on the host. Works 1418only with security models "mapped-xattr" and "mapped-file". 1419@item mount_tag=@var{mount_tag} 1420Specifies the tag name to be used by the guest to mount this export point. 1421@item multidevs=@var{multidevs} 1422Specifies how to deal with multiple devices being shared with a 9p export. 1423Supported behaviours are either "remap", "forbid" or "warn". The latter is 1424the default behaviour on which virtfs 9p expects only one device to be 1425shared with the same export, and if more than one device is shared and 1426accessed via the same 9p export then only a warning message is logged 1427(once) by qemu on host side. In order to avoid file ID collisions on guest 1428you should either create a separate virtfs export for each device to be 1429shared with guests (recommended way) or you might use "remap" instead which 1430allows you to share multiple devices with only one export instead, which is 1431achieved by remapping the original inode numbers from host to guest in a 1432way that would prevent such collisions. Remapping inodes in such use cases 1433is required because the original device IDs from host are never passed and 1434exposed on guest. Instead all files of an export shared with virtfs always 1435share the same device id on guest. So two files with identical inode 1436numbers but from actually different devices on host would otherwise cause a 1437file ID collision and hence potential misbehaviours on guest. "forbid" on 1438the other hand assumes like "warn" that only one device is shared by the 1439same export, however it will not only log a warning message but also 1440deny access to additional devices on guest. Note though that "forbid" does 1441currently not block all possible file access operations (e.g. readdir() 1442would still return entries from other devices). 1443@end table 1444ETEXI 1445 1446DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 1447 "-virtfs_synth Create synthetic file system image\n", 1448 QEMU_ARCH_ALL) 1449STEXI 1450@item -virtfs_synth 1451@findex -virtfs_synth 1452Create synthetic file system image. Note that this option is now deprecated. 1453Please use @code{-fsdev synth} and @code{-device virtio-9p-...} instead. 1454ETEXI 1455 1456DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 1457 "-iscsi [user=user][,password=password]\n" 1458 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 1459 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 1460 " [,timeout=timeout]\n" 1461 " iSCSI session parameters\n", QEMU_ARCH_ALL) 1462 1463STEXI 1464@item -iscsi 1465@findex -iscsi 1466Configure iSCSI session parameters. 1467ETEXI 1468 1469STEXI 1470@end table 1471ETEXI 1472DEFHEADING() 1473 1474DEFHEADING(USB options:) 1475STEXI 1476@table @option 1477ETEXI 1478 1479DEF("usb", 0, QEMU_OPTION_usb, 1480 "-usb enable on-board USB host controller (if not enabled by default)\n", 1481 QEMU_ARCH_ALL) 1482STEXI 1483@item -usb 1484@findex -usb 1485Enable USB emulation on machine types with an on-board USB host controller (if 1486not enabled by default). Note that on-board USB host controllers may not 1487support USB 3.0. In this case @option{-device qemu-xhci} can be used instead 1488on machines with PCI. 1489ETEXI 1490 1491DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 1492 "-usbdevice name add the host or guest USB device 'name'\n", 1493 QEMU_ARCH_ALL) 1494STEXI 1495 1496@item -usbdevice @var{devname} 1497@findex -usbdevice 1498Add the USB device @var{devname}. Note that this option is deprecated, 1499please use @code{-device usb-...} instead. @xref{usb_devices}. 1500 1501@table @option 1502 1503@item mouse 1504Virtual Mouse. This will override the PS/2 mouse emulation when activated. 1505 1506@item tablet 1507Pointer device that uses absolute coordinates (like a touchscreen). This 1508means QEMU is able to report the mouse position without having to grab the 1509mouse. Also overrides the PS/2 mouse emulation when activated. 1510 1511@item braille 1512Braille device. This will use BrlAPI to display the braille output on a real 1513or fake device. 1514 1515@end table 1516ETEXI 1517 1518STEXI 1519@end table 1520ETEXI 1521DEFHEADING() 1522 1523DEFHEADING(Display options:) 1524STEXI 1525@table @option 1526ETEXI 1527 1528DEF("display", HAS_ARG, QEMU_OPTION_display, 1529 "-display spice-app[,gl=on|off]\n" 1530 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 1531 " [,window_close=on|off][,gl=on|core|es|off]\n" 1532 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 1533 "-display vnc=<display>[,<optargs>]\n" 1534 "-display curses[,charset=<encoding>]\n" 1535 "-display none\n" 1536 "-display egl-headless[,rendernode=<file>]" 1537 " select display type\n" 1538 "The default display is equivalent to\n" 1539#if defined(CONFIG_GTK) 1540 "\t\"-display gtk\"\n" 1541#elif defined(CONFIG_SDL) 1542 "\t\"-display sdl\"\n" 1543#elif defined(CONFIG_COCOA) 1544 "\t\"-display cocoa\"\n" 1545#elif defined(CONFIG_VNC) 1546 "\t\"-vnc localhost:0,to=99,id=default\"\n" 1547#else 1548 "\t\"-display none\"\n" 1549#endif 1550 , QEMU_ARCH_ALL) 1551STEXI 1552@item -display @var{type} 1553@findex -display 1554Select type of display to use. This option is a replacement for the 1555old style -sdl/-curses/... options. Valid values for @var{type} are 1556@table @option 1557@item sdl 1558Display video output via SDL (usually in a separate graphics 1559window; see the SDL documentation for other possibilities). 1560@item curses 1561Display video output via curses. For graphics device models which 1562support a text mode, QEMU can display this output using a 1563curses/ncurses interface. Nothing is displayed when the graphics 1564device is in graphical mode or if the graphics device does not support 1565a text mode. Generally only the VGA device models support text mode. 1566The font charset used by the guest can be specified with the 1567@code{charset} option, for example @code{charset=CP850} for IBM CP850 1568encoding. The default is @code{CP437}. 1569@item none 1570Do not display video output. The guest will still see an emulated 1571graphics card, but its output will not be displayed to the QEMU 1572user. This option differs from the -nographic option in that it 1573only affects what is done with video output; -nographic also changes 1574the destination of the serial and parallel port data. 1575@item gtk 1576Display video output in a GTK window. This interface provides drop-down 1577menus and other UI elements to configure and control the VM during 1578runtime. 1579@item vnc 1580Start a VNC server on display <arg> 1581@item egl-headless 1582Offload all OpenGL operations to a local DRI device. For any graphical display, 1583this display needs to be paired with either VNC or SPICE displays. 1584@item spice-app 1585Start QEMU as a Spice server and launch the default Spice client 1586application. The Spice server will redirect the serial consoles and 1587QEMU monitors. (Since 4.0) 1588@end table 1589ETEXI 1590 1591DEF("nographic", 0, QEMU_OPTION_nographic, 1592 "-nographic disable graphical output and redirect serial I/Os to console\n", 1593 QEMU_ARCH_ALL) 1594STEXI 1595@item -nographic 1596@findex -nographic 1597Normally, if QEMU is compiled with graphical window support, it displays 1598output such as guest graphics, guest console, and the QEMU monitor in a 1599window. With this option, you can totally disable graphical output so 1600that QEMU is a simple command line application. The emulated serial port 1601is redirected on the console and muxed with the monitor (unless 1602redirected elsewhere explicitly). Therefore, you can still use QEMU to 1603debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1604switching between the console and monitor. 1605ETEXI 1606 1607DEF("curses", 0, QEMU_OPTION_curses, 1608 "-curses shorthand for -display curses\n", 1609 QEMU_ARCH_ALL) 1610STEXI 1611@item -curses 1612@findex -curses 1613Normally, if QEMU is compiled with graphical window support, it displays 1614output such as guest graphics, guest console, and the QEMU monitor in a 1615window. With this option, QEMU can display the VGA output when in text 1616mode using a curses/ncurses interface. Nothing is displayed in graphical 1617mode. 1618ETEXI 1619 1620DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1621 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1622 QEMU_ARCH_ALL) 1623STEXI 1624@item -alt-grab 1625@findex -alt-grab 1626Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1627affects the special keys (for fullscreen, monitor-mode switching, etc). 1628ETEXI 1629 1630DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1631 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1632 QEMU_ARCH_ALL) 1633STEXI 1634@item -ctrl-grab 1635@findex -ctrl-grab 1636Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1637affects the special keys (for fullscreen, monitor-mode switching, etc). 1638ETEXI 1639 1640DEF("no-quit", 0, QEMU_OPTION_no_quit, 1641 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1642STEXI 1643@item -no-quit 1644@findex -no-quit 1645Disable SDL window close capability. 1646ETEXI 1647 1648DEF("sdl", 0, QEMU_OPTION_sdl, 1649 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1650STEXI 1651@item -sdl 1652@findex -sdl 1653Enable SDL. 1654ETEXI 1655 1656DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1657 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1658 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1659 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1660 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1661 " [,tls-ciphers=<list>]\n" 1662 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1663 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1664 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1665 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1666 " [,jpeg-wan-compression=[auto|never|always]]\n" 1667 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1668 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1669 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1670 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1671 " [,gl=[on|off]][,rendernode=<file>]\n" 1672 " enable spice\n" 1673 " at least one of {port, tls-port} is mandatory\n", 1674 QEMU_ARCH_ALL) 1675STEXI 1676@item -spice @var{option}[,@var{option}[,...]] 1677@findex -spice 1678Enable the spice remote desktop protocol. Valid options are 1679 1680@table @option 1681 1682@item port=<nr> 1683Set the TCP port spice is listening on for plaintext channels. 1684 1685@item addr=<addr> 1686Set the IP address spice is listening on. Default is any address. 1687 1688@item ipv4 1689@itemx ipv6 1690@itemx unix 1691Force using the specified IP version. 1692 1693@item password=<secret> 1694Set the password you need to authenticate. 1695 1696@item sasl 1697Require that the client use SASL to authenticate with the spice. 1698The exact choice of authentication method used is controlled from the 1699system / user's SASL configuration file for the 'qemu' service. This 1700is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1701unprivileged user, an environment variable SASL_CONF_PATH can be used 1702to make it search alternate locations for the service config. 1703While some SASL auth methods can also provide data encryption (eg GSSAPI), 1704it is recommended that SASL always be combined with the 'tls' and 1705'x509' settings to enable use of SSL and server certificates. This 1706ensures a data encryption preventing compromise of authentication 1707credentials. 1708 1709@item disable-ticketing 1710Allow client connects without authentication. 1711 1712@item disable-copy-paste 1713Disable copy paste between the client and the guest. 1714 1715@item disable-agent-file-xfer 1716Disable spice-vdagent based file-xfer between the client and the guest. 1717 1718@item tls-port=<nr> 1719Set the TCP port spice is listening on for encrypted channels. 1720 1721@item x509-dir=<dir> 1722Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1723 1724@item x509-key-file=<file> 1725@itemx x509-key-password=<file> 1726@itemx x509-cert-file=<file> 1727@itemx x509-cacert-file=<file> 1728@itemx x509-dh-key-file=<file> 1729The x509 file names can also be configured individually. 1730 1731@item tls-ciphers=<list> 1732Specify which ciphers to use. 1733 1734@item tls-channel=[main|display|cursor|inputs|record|playback] 1735@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1736Force specific channel to be used with or without TLS encryption. The 1737options can be specified multiple times to configure multiple 1738channels. The special name "default" can be used to set the default 1739mode. For channels which are not explicitly forced into one mode the 1740spice client is allowed to pick tls/plaintext as he pleases. 1741 1742@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1743Configure image compression (lossless). 1744Default is auto_glz. 1745 1746@item jpeg-wan-compression=[auto|never|always] 1747@itemx zlib-glz-wan-compression=[auto|never|always] 1748Configure wan image compression (lossy for slow links). 1749Default is auto. 1750 1751@item streaming-video=[off|all|filter] 1752Configure video stream detection. Default is off. 1753 1754@item agent-mouse=[on|off] 1755Enable/disable passing mouse events via vdagent. Default is on. 1756 1757@item playback-compression=[on|off] 1758Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1759 1760@item seamless-migration=[on|off] 1761Enable/disable spice seamless migration. Default is off. 1762 1763@item gl=[on|off] 1764Enable/disable OpenGL context. Default is off. 1765 1766@item rendernode=<file> 1767DRM render node for OpenGL rendering. If not specified, it will pick 1768the first available. (Since 2.9) 1769 1770@end table 1771ETEXI 1772 1773DEF("portrait", 0, QEMU_OPTION_portrait, 1774 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1775 QEMU_ARCH_ALL) 1776STEXI 1777@item -portrait 1778@findex -portrait 1779Rotate graphical output 90 deg left (only PXA LCD). 1780ETEXI 1781 1782DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1783 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1784 QEMU_ARCH_ALL) 1785STEXI 1786@item -rotate @var{deg} 1787@findex -rotate 1788Rotate graphical output some deg left (only PXA LCD). 1789ETEXI 1790 1791DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1792 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1793 " select video card type\n", QEMU_ARCH_ALL) 1794STEXI 1795@item -vga @var{type} 1796@findex -vga 1797Select type of VGA card to emulate. Valid values for @var{type} are 1798@table @option 1799@item cirrus 1800Cirrus Logic GD5446 Video card. All Windows versions starting from 1801Windows 95 should recognize and use this graphic card. For optimal 1802performances, use 16 bit color depth in the guest and the host OS. 1803(This card was the default before QEMU 2.2) 1804@item std 1805Standard VGA card with Bochs VBE extensions. If your guest OS 1806supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1807to use high resolution modes (>= 1280x1024x16) then you should use 1808this option. (This card is the default since QEMU 2.2) 1809@item vmware 1810VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1811recent XFree86/XOrg server or Windows guest with a driver for this 1812card. 1813@item qxl 1814QXL paravirtual graphic card. It is VGA compatible (including VESA 18152.0 VBE support). Works best with qxl guest drivers installed though. 1816Recommended choice when using the spice protocol. 1817@item tcx 1818(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1819sun4m machines and offers both 8-bit and 24-bit colour depths at a 1820fixed resolution of 1024x768. 1821@item cg3 1822(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1823for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1824resolutions aimed at people wishing to run older Solaris versions. 1825@item virtio 1826Virtio VGA card. 1827@item none 1828Disable VGA card. 1829@end table 1830ETEXI 1831 1832DEF("full-screen", 0, QEMU_OPTION_full_screen, 1833 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1834STEXI 1835@item -full-screen 1836@findex -full-screen 1837Start in full screen. 1838ETEXI 1839 1840DEF("g", 1, QEMU_OPTION_g , 1841 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1842 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1843STEXI 1844@item -g @var{width}x@var{height}[x@var{depth}] 1845@findex -g 1846Set the initial graphical resolution and depth (PPC, SPARC only). 1847ETEXI 1848 1849DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1850 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1851STEXI 1852@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1853@findex -vnc 1854Normally, if QEMU is compiled with graphical window support, it displays 1855output such as guest graphics, guest console, and the QEMU monitor in a 1856window. With this option, you can have QEMU listen on VNC display 1857@var{display} and redirect the VGA display over the VNC session. It is 1858very useful to enable the usb tablet device when using this option 1859(option @option{-device usb-tablet}). When using the VNC display, you 1860must use the @option{-k} parameter to set the keyboard layout if you are 1861not using en-us. Valid syntax for the @var{display} is 1862 1863@table @option 1864 1865@item to=@var{L} 1866 1867With this option, QEMU will try next available VNC @var{display}s, until the 1868number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1869available, e.g. port 5900+@var{display} is already used by another 1870application. By default, to=0. 1871 1872@item @var{host}:@var{d} 1873 1874TCP connections will only be allowed from @var{host} on display @var{d}. 1875By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1876be omitted in which case the server will accept connections from any host. 1877 1878@item unix:@var{path} 1879 1880Connections will be allowed over UNIX domain sockets where @var{path} is the 1881location of a unix socket to listen for connections on. 1882 1883@item none 1884 1885VNC is initialized but not started. The monitor @code{change} command 1886can be used to later start the VNC server. 1887 1888@end table 1889 1890Following the @var{display} value there may be one or more @var{option} flags 1891separated by commas. Valid options are 1892 1893@table @option 1894 1895@item reverse 1896 1897Connect to a listening VNC client via a ``reverse'' connection. The 1898client is specified by the @var{display}. For reverse network 1899connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1900is a TCP port number, not a display number. 1901 1902@item websocket 1903 1904Opens an additional TCP listening port dedicated to VNC Websocket connections. 1905If a bare @var{websocket} option is given, the Websocket port is 19065700+@var{display}. An alternative port can be specified with the 1907syntax @code{websocket}=@var{port}. 1908 1909If @var{host} is specified connections will only be allowed from this host. 1910It is possible to control the websocket listen address independently, using 1911the syntax @code{websocket}=@var{host}:@var{port}. 1912 1913If no TLS credentials are provided, the websocket connection runs in 1914unencrypted mode. If TLS credentials are provided, the websocket connection 1915requires encrypted client connections. 1916 1917@item password 1918 1919Require that password based authentication is used for client connections. 1920 1921The password must be set separately using the @code{set_password} command in 1922the @ref{pcsys_monitor}. The syntax to change your password is: 1923@code{set_password <protocol> <password>} where <protocol> could be either 1924"vnc" or "spice". 1925 1926If you would like to change <protocol> password expiration, you should use 1927@code{expire_password <protocol> <expiration-time>} where expiration time could 1928be one of the following options: now, never, +seconds or UNIX time of 1929expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1930to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1931date and time). 1932 1933You can also use keywords "now" or "never" for the expiration time to 1934allow <protocol> password to expire immediately or never expire. 1935 1936@item tls-creds=@var{ID} 1937 1938Provides the ID of a set of TLS credentials to use to secure the 1939VNC server. They will apply to both the normal VNC server socket 1940and the websocket socket (if enabled). Setting TLS credentials 1941will cause the VNC server socket to enable the VeNCrypt auth 1942mechanism. The credentials should have been previously created 1943using the @option{-object tls-creds} argument. 1944 1945@item tls-authz=@var{ID} 1946 1947Provides the ID of the QAuthZ authorization object against which 1948the client's x509 distinguished name will validated. This object is 1949only resolved at time of use, so can be deleted and recreated on the 1950fly while the VNC server is active. If missing, it will default 1951to denying access. 1952 1953@item sasl 1954 1955Require that the client use SASL to authenticate with the VNC server. 1956The exact choice of authentication method used is controlled from the 1957system / user's SASL configuration file for the 'qemu' service. This 1958is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1959unprivileged user, an environment variable SASL_CONF_PATH can be used 1960to make it search alternate locations for the service config. 1961While some SASL auth methods can also provide data encryption (eg GSSAPI), 1962it is recommended that SASL always be combined with the 'tls' and 1963'x509' settings to enable use of SSL and server certificates. This 1964ensures a data encryption preventing compromise of authentication 1965credentials. See the @ref{vnc_security} section for details on using 1966SASL authentication. 1967 1968@item sasl-authz=@var{ID} 1969 1970Provides the ID of the QAuthZ authorization object against which 1971the client's SASL username will validated. This object is 1972only resolved at time of use, so can be deleted and recreated on the 1973fly while the VNC server is active. If missing, it will default 1974to denying access. 1975 1976@item acl 1977 1978Legacy method for enabling authorization of clients against the 1979x509 distinguished name and SASL username. It results in the creation 1980of two @code{authz-list} objects with IDs of @code{vnc.username} and 1981@code{vnc.x509dname}. The rules for these objects must be configured 1982with the HMP ACL commands. 1983 1984This option is deprecated and should no longer be used. The new 1985@option{sasl-authz} and @option{tls-authz} options are a 1986replacement. 1987 1988@item lossy 1989 1990Enable lossy compression methods (gradient, JPEG, ...). If this 1991option is set, VNC client may receive lossy framebuffer updates 1992depending on its encoding settings. Enabling this option can save 1993a lot of bandwidth at the expense of quality. 1994 1995@item non-adaptive 1996 1997Disable adaptive encodings. Adaptive encodings are enabled by default. 1998An adaptive encoding will try to detect frequently updated screen regions, 1999and send updates in these regions using a lossy encoding (like JPEG). 2000This can be really helpful to save bandwidth when playing videos. Disabling 2001adaptive encodings restores the original static behavior of encodings 2002like Tight. 2003 2004@item share=[allow-exclusive|force-shared|ignore] 2005 2006Set display sharing policy. 'allow-exclusive' allows clients to ask 2007for exclusive access. As suggested by the rfb spec this is 2008implemented by dropping other connections. Connecting multiple 2009clients in parallel requires all clients asking for a shared session 2010(vncviewer: -shared switch). This is the default. 'force-shared' 2011disables exclusive client access. Useful for shared desktop sessions, 2012where you don't want someone forgetting specify -shared disconnect 2013everybody else. 'ignore' completely ignores the shared flag and 2014allows everybody connect unconditionally. Doesn't conform to the rfb 2015spec but is traditional QEMU behavior. 2016 2017@item key-delay-ms 2018 2019Set keyboard delay, for key down and key up events, in milliseconds. 2020Default is 10. Keyboards are low-bandwidth devices, so this slowdown 2021can help the device and guest to keep up and not lose events in case 2022events are arriving in bulk. Possible causes for the latter are flaky 2023network connections, or scripts for automated testing. 2024 2025@item audiodev=@var{audiodev} 2026 2027Use the specified @var{audiodev} when the VNC client requests audio 2028transmission. When not using an -audiodev argument, this option must 2029be omitted, otherwise is must be present and specify a valid audiodev. 2030 2031@end table 2032ETEXI 2033 2034STEXI 2035@end table 2036ETEXI 2037ARCHHEADING(, QEMU_ARCH_I386) 2038 2039ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 2040STEXI 2041@table @option 2042ETEXI 2043 2044DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 2045 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 2046 QEMU_ARCH_I386) 2047STEXI 2048@item -win2k-hack 2049@findex -win2k-hack 2050Use it when installing Windows 2000 to avoid a disk full bug. After 2051Windows 2000 is installed, you no longer need this option (this option 2052slows down the IDE transfers). 2053ETEXI 2054 2055DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 2056 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 2057 QEMU_ARCH_I386) 2058STEXI 2059@item -no-fd-bootchk 2060@findex -no-fd-bootchk 2061Disable boot signature checking for floppy disks in BIOS. May 2062be needed to boot from old floppy disks. 2063ETEXI 2064 2065DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 2066 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 2067STEXI 2068@item -no-acpi 2069@findex -no-acpi 2070Disable ACPI (Advanced Configuration and Power Interface) support. Use 2071it if your guest OS complains about ACPI problems (PC target machine 2072only). 2073ETEXI 2074 2075DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 2076 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 2077STEXI 2078@item -no-hpet 2079@findex -no-hpet 2080Disable HPET support. 2081ETEXI 2082 2083DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 2084 "-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" 2085 " ACPI table description\n", QEMU_ARCH_I386) 2086STEXI 2087@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}]...] 2088@findex -acpitable 2089Add ACPI table with specified header fields and context from specified files. 2090For file=, take whole ACPI table from the specified files, including all 2091ACPI headers (possible overridden by other options). 2092For data=, only data 2093portion of the table is used, all header information is specified in the 2094command line. 2095If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 2096fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 2097to ensure the field matches required by the Microsoft SLIC spec and the ACPI 2098spec. 2099ETEXI 2100 2101DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 2102 "-smbios file=binary\n" 2103 " load SMBIOS entry from binary file\n" 2104 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 2105 " [,uefi=on|off]\n" 2106 " specify SMBIOS type 0 fields\n" 2107 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 2108 " [,uuid=uuid][,sku=str][,family=str]\n" 2109 " specify SMBIOS type 1 fields\n" 2110 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 2111 " [,asset=str][,location=str]\n" 2112 " specify SMBIOS type 2 fields\n" 2113 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 2114 " [,sku=str]\n" 2115 " specify SMBIOS type 3 fields\n" 2116 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 2117 " [,asset=str][,part=str]\n" 2118 " specify SMBIOS type 4 fields\n" 2119 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 2120 " [,asset=str][,part=str][,speed=%d]\n" 2121 " specify SMBIOS type 17 fields\n", 2122 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 2123STEXI 2124@item -smbios file=@var{binary} 2125@findex -smbios 2126Load SMBIOS entry from binary file. 2127 2128@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 2129Specify SMBIOS type 0 fields 2130 2131@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}] 2132Specify SMBIOS type 1 fields 2133 2134@item -smbios type=2[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,location=@var{str}] 2135Specify SMBIOS type 2 fields 2136 2137@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 2138Specify SMBIOS type 3 fields 2139 2140@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 2141Specify SMBIOS type 4 fields 2142 2143@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}] 2144Specify SMBIOS type 17 fields 2145ETEXI 2146 2147STEXI 2148@end table 2149ETEXI 2150DEFHEADING() 2151 2152DEFHEADING(Network options:) 2153STEXI 2154@table @option 2155ETEXI 2156 2157DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 2158#ifdef CONFIG_SLIRP 2159 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 2160 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 2161 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 2162 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n" 2163 " [,tftp=dir][,tftp-server-name=name][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 2164#ifndef _WIN32 2165 "[,smb=dir[,smbserver=addr]]\n" 2166#endif 2167 " configure a user mode network backend with ID 'str',\n" 2168 " its DHCP server and optional services\n" 2169#endif 2170#ifdef _WIN32 2171 "-netdev tap,id=str,ifname=name\n" 2172 " configure a host TAP network backend with ID 'str'\n" 2173#else 2174 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 2175 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 2176 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 2177 " [,poll-us=n]\n" 2178 " configure a host TAP network backend with ID 'str'\n" 2179 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 2180 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 2181 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 2182 " to deconfigure it\n" 2183 " use '[down]script=no' to disable script execution\n" 2184 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 2185 " configure it\n" 2186 " use 'fd=h' to connect to an already opened TAP interface\n" 2187 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 2188 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 2189 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 2190 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 2191 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 2192 " use vhost=on to enable experimental in kernel accelerator\n" 2193 " (only has effect for virtio guests which use MSIX)\n" 2194 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 2195 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 2196 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 2197 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 2198 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 2199 " spent on busy polling for vhost net\n" 2200 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 2201 " configure a host TAP network backend with ID 'str' that is\n" 2202 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 2203 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 2204#endif 2205#ifdef __linux__ 2206 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 2207 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 2208 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 2209 " [,rxcookie=rxcookie][,offset=offset]\n" 2210 " configure a network backend with ID 'str' connected to\n" 2211 " an Ethernet over L2TPv3 pseudowire.\n" 2212 " Linux kernel 3.3+ as well as most routers can talk\n" 2213 " L2TPv3. This transport allows connecting a VM to a VM,\n" 2214 " VM to a router and even VM to Host. It is a nearly-universal\n" 2215 " standard (RFC3391). Note - this implementation uses static\n" 2216 " pre-configured tunnels (same as the Linux kernel).\n" 2217 " use 'src=' to specify source address\n" 2218 " use 'dst=' to specify destination address\n" 2219 " use 'udp=on' to specify udp encapsulation\n" 2220 " use 'srcport=' to specify source udp port\n" 2221 " use 'dstport=' to specify destination udp port\n" 2222 " use 'ipv6=on' to force v6\n" 2223 " L2TPv3 uses cookies to prevent misconfiguration as\n" 2224 " well as a weak security measure\n" 2225 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 2226 " use 'txcookie=0x012345678' to specify a txcookie\n" 2227 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 2228 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 2229 " use 'pincounter=on' to work around broken counter handling in peer\n" 2230 " use 'offset=X' to add an extra offset between header and data\n" 2231#endif 2232 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 2233 " configure a network backend to connect to another network\n" 2234 " using a socket connection\n" 2235 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 2236 " configure a network backend to connect to a multicast maddr and port\n" 2237 " use 'localaddr=addr' to specify the host address to send packets from\n" 2238 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 2239 " configure a network backend to connect to another network\n" 2240 " using an UDP tunnel\n" 2241#ifdef CONFIG_VDE 2242 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 2243 " configure a network backend to connect to port 'n' of a vde switch\n" 2244 " running on host and listening for incoming connections on 'socketpath'.\n" 2245 " Use group 'groupname' and mode 'octalmode' to change default\n" 2246 " ownership and permissions for communication port.\n" 2247#endif 2248#ifdef CONFIG_NETMAP 2249 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 2250 " attach to the existing netmap-enabled network interface 'name', or to a\n" 2251 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 2252 " netmap device, defaults to '/dev/netmap')\n" 2253#endif 2254#ifdef CONFIG_POSIX 2255 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 2256 " configure a vhost-user network, backed by a chardev 'dev'\n" 2257#endif 2258 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n" 2259 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL) 2260DEF("nic", HAS_ARG, QEMU_OPTION_nic, 2261 "-nic [tap|bridge|" 2262#ifdef CONFIG_SLIRP 2263 "user|" 2264#endif 2265#ifdef __linux__ 2266 "l2tpv3|" 2267#endif 2268#ifdef CONFIG_VDE 2269 "vde|" 2270#endif 2271#ifdef CONFIG_NETMAP 2272 "netmap|" 2273#endif 2274#ifdef CONFIG_POSIX 2275 "vhost-user|" 2276#endif 2277 "socket][,option][,...][mac=macaddr]\n" 2278 " initialize an on-board / default host NIC (using MAC address\n" 2279 " macaddr) and connect it to the given host network backend\n" 2280 "-nic none use it alone to have zero network devices (the default is to\n" 2281 " provided a 'user' network connection)\n", 2282 QEMU_ARCH_ALL) 2283DEF("net", HAS_ARG, QEMU_OPTION_net, 2284 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 2285 " configure or create an on-board (or machine default) NIC and\n" 2286 " connect it to hub 0 (please use -nic unless you need a hub)\n" 2287 "-net [" 2288#ifdef CONFIG_SLIRP 2289 "user|" 2290#endif 2291 "tap|" 2292 "bridge|" 2293#ifdef CONFIG_VDE 2294 "vde|" 2295#endif 2296#ifdef CONFIG_NETMAP 2297 "netmap|" 2298#endif 2299 "socket][,option][,option][,...]\n" 2300 " old way to initialize a host network interface\n" 2301 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 2302STEXI 2303@item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn] 2304@findex -nic 2305This option is a shortcut for configuring both the on-board (default) guest 2306NIC hardware and the host network backend in one go. The host backend options 2307are the same as with the corresponding @option{-netdev} options below. 2308The guest NIC model can be set with @option{model=@var{modelname}}. 2309Use @option{model=help} to list the available device types. 2310The hardware MAC address can be set with @option{mac=@var{macaddr}}. 2311 2312The following two example do exactly the same, to show how @option{-nic} can 2313be used to shorten the command line length (note that the e1000 is the default 2314on i386, so the @option{model=e1000} parameter could even be omitted here, too): 2315@example 2316@value{qemu_system} -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32 2317@value{qemu_system} -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32 2318@end example 2319 2320@item -nic none 2321Indicate that no network devices should be configured. It is used to override 2322the default configuration (default NIC with ``user'' host network backend) 2323which is activated if no other networking options are provided. 2324 2325@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 2326@findex -netdev 2327Configure user mode host network backend which requires no administrator 2328privilege to run. Valid options are: 2329 2330@table @option 2331@item id=@var{id} 2332Assign symbolic name for use in monitor commands. 2333 2334@item ipv4=on|off and ipv6=on|off 2335Specify that either IPv4 or IPv6 must be enabled. If neither is specified 2336both protocols are enabled. 2337 2338@item net=@var{addr}[/@var{mask}] 2339Set IP network address the guest will see. Optionally specify the netmask, 2340either in the form a.b.c.d or as number of valid top-most bits. Default is 234110.0.2.0/24. 2342 2343@item host=@var{addr} 2344Specify the guest-visible address of the host. Default is the 2nd IP in the 2345guest network, i.e. x.x.x.2. 2346 2347@item ipv6-net=@var{addr}[/@var{int}] 2348Set IPv6 network address the guest will see (default is fec0::/64). The 2349network prefix is given in the usual hexadecimal IPv6 address 2350notation. The prefix size is optional, and is given as the number of 2351valid top-most bits (default is 64). 2352 2353@item ipv6-host=@var{addr} 2354Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 2355the guest network, i.e. xxxx::2. 2356 2357@item restrict=on|off 2358If this option is enabled, the guest will be isolated, i.e. it will not be 2359able to contact the host and no guest IP packets will be routed over the host 2360to the outside. This option does not affect any explicitly set forwarding rules. 2361 2362@item hostname=@var{name} 2363Specifies the client hostname reported by the built-in DHCP server. 2364 2365@item dhcpstart=@var{addr} 2366Specify the first of the 16 IPs the built-in DHCP server can assign. Default 2367is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 2368 2369@item dns=@var{addr} 2370Specify the guest-visible address of the virtual nameserver. The address must 2371be different from the host address. Default is the 3rd IP in the guest network, 2372i.e. x.x.x.3. 2373 2374@item ipv6-dns=@var{addr} 2375Specify the guest-visible address of the IPv6 virtual nameserver. The address 2376must be different from the host address. Default is the 3rd IP in the guest 2377network, i.e. xxxx::3. 2378 2379@item dnssearch=@var{domain} 2380Provides an entry for the domain-search list sent by the built-in 2381DHCP server. More than one domain suffix can be transmitted by specifying 2382this option multiple times. If supported, this will cause the guest to 2383automatically try to append the given domain suffix(es) in case a domain name 2384can not be resolved. 2385 2386Example: 2387@example 2388@value{qemu_system} -nic user,dnssearch=mgmt.example.org,dnssearch=example.org 2389@end example 2390 2391@item domainname=@var{domain} 2392Specifies the client domain name reported by the built-in DHCP server. 2393 2394@item tftp=@var{dir} 2395When using the user mode network stack, activate a built-in TFTP 2396server. The files in @var{dir} will be exposed as the root of a TFTP server. 2397The TFTP client on the guest must be configured in binary mode (use the command 2398@code{bin} of the Unix TFTP client). 2399 2400@item tftp-server-name=@var{name} 2401In BOOTP reply, broadcast @var{name} as the "TFTP server name" (RFC2132 option 240266). This can be used to advise the guest to load boot files or configurations 2403from a different server than the host address. 2404 2405@item bootfile=@var{file} 2406When using the user mode network stack, broadcast @var{file} as the BOOTP 2407filename. In conjunction with @option{tftp}, this can be used to network boot 2408a guest from a local directory. 2409 2410Example (using pxelinux): 2411@example 2412@value{qemu_system} -hda linux.img -boot n -device e1000,netdev=n1 \ 2413 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2414@end example 2415 2416@item smb=@var{dir}[,smbserver=@var{addr}] 2417When using the user mode network stack, activate a built-in SMB 2418server so that Windows OSes can access to the host files in @file{@var{dir}} 2419transparently. The IP address of the SMB server can be set to @var{addr}. By 2420default the 4th IP in the guest network is used, i.e. x.x.x.4. 2421 2422In the guest Windows OS, the line: 2423@example 242410.0.2.4 smbserver 2425@end example 2426must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2427or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2428 2429Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2430 2431Note that a SAMBA server must be installed on the host OS. 2432 2433@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2434Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2435the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2436@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2437given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2438be bound to a specific host interface. If no connection type is set, TCP is 2439used. This option can be given multiple times. 2440 2441For example, to redirect host X11 connection from screen 1 to guest 2442screen 0, use the following: 2443 2444@example 2445# on the host 2446@value{qemu_system} -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 2447# this host xterm should open in the guest X11 server 2448xterm -display :1 2449@end example 2450 2451To redirect telnet connections from host port 5555 to telnet port on 2452the guest, use the following: 2453 2454@example 2455# on the host 2456@value{qemu_system} -nic user,hostfwd=tcp::5555-:23 2457telnet localhost 5555 2458@end example 2459 2460Then when you use on the host @code{telnet localhost 5555}, you 2461connect to the guest telnet server. 2462 2463@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2464@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2465Forward guest TCP connections to the IP address @var{server} on port @var{port} 2466to the character device @var{dev} or to a program executed by @var{cmd:command} 2467which gets spawned for each connection. This option can be given multiple times. 2468 2469You can either use a chardev directly and have that one used throughout QEMU's 2470lifetime, like in the following example: 2471 2472@example 2473# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2474# the guest accesses it 2475@value{qemu_system} -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 2476@end example 2477 2478Or you can execute a command on every TCP connection established by the guest, 2479so that QEMU behaves similar to an inetd process for that virtual server: 2480 2481@example 2482# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2483# and connect the TCP stream to its stdin/stdout 2484@value{qemu_system} -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2485@end example 2486 2487@end table 2488 2489@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2490Configure a host TAP network backend with ID @var{id}. 2491 2492Use the network script @var{file} to configure it and the network script 2493@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2494automatically provides one. The default network configure script is 2495@file{/etc/qemu-ifup} and the default network deconfigure script is 2496@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2497to disable script execution. 2498 2499If running QEMU as an unprivileged user, use the network helper 2500@var{helper} to configure the TAP interface and attach it to the bridge. 2501The default network helper executable is @file{/path/to/qemu-bridge-helper} 2502and the default bridge device is @file{br0}. 2503 2504@option{fd}=@var{h} can be used to specify the handle of an already 2505opened host TAP interface. 2506 2507Examples: 2508 2509@example 2510#launch a QEMU instance with the default network script 2511@value{qemu_system} linux.img -nic tap 2512@end example 2513 2514@example 2515#launch a QEMU instance with two NICs, each one connected 2516#to a TAP device 2517@value{qemu_system} linux.img \ 2518 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \ 2519 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1 2520@end example 2521 2522@example 2523#launch a QEMU instance with the default network helper to 2524#connect a TAP device to bridge br0 2525@value{qemu_system} linux.img -device virtio-net-pci,netdev=n1 \ 2526 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper" 2527@end example 2528 2529@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2530Connect a host TAP network interface to a host bridge device. 2531 2532Use the network helper @var{helper} to configure the TAP interface and 2533attach it to the bridge. The default network helper executable is 2534@file{/path/to/qemu-bridge-helper} and the default bridge 2535device is @file{br0}. 2536 2537Examples: 2538 2539@example 2540#launch a QEMU instance with the default network helper to 2541#connect a TAP device to bridge br0 2542@value{qemu_system} linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1 2543@end example 2544 2545@example 2546#launch a QEMU instance with the default network helper to 2547#connect a TAP device to bridge qemubr0 2548@value{qemu_system} linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1 2549@end example 2550 2551@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2552 2553This host network backend can be used to connect the guest's network to 2554another QEMU virtual machine using a TCP socket connection. If @option{listen} 2555is specified, QEMU waits for incoming connections on @var{port} 2556(@var{host} is optional). @option{connect} is used to connect to 2557another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2558specifies an already opened TCP socket. 2559 2560Example: 2561@example 2562# launch a first QEMU instance 2563@value{qemu_system} linux.img \ 2564 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2565 -netdev socket,id=n1,listen=:1234 2566# connect the network of this instance to the network of the first instance 2567@value{qemu_system} linux.img \ 2568 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2569 -netdev socket,id=n2,connect=127.0.0.1:1234 2570@end example 2571 2572@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2573 2574Configure a socket host network backend to share the guest's network traffic 2575with another QEMU virtual machines using a UDP multicast socket, effectively 2576making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. 2577NOTES: 2578@enumerate 2579@item 2580Several QEMU can be running on different hosts and share same bus (assuming 2581correct multicast setup for these hosts). 2582@item 2583mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2584@url{http://user-mode-linux.sf.net}. 2585@item 2586Use @option{fd=h} to specify an already opened UDP multicast socket. 2587@end enumerate 2588 2589Example: 2590@example 2591# launch one QEMU instance 2592@value{qemu_system} linux.img \ 2593 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2594 -netdev socket,id=n1,mcast=230.0.0.1:1234 2595# launch another QEMU instance on same "bus" 2596@value{qemu_system} linux.img \ 2597 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2598 -netdev socket,id=n2,mcast=230.0.0.1:1234 2599# launch yet another QEMU instance on same "bus" 2600@value{qemu_system} linux.img \ 2601 -device e1000,netdev=n3,mac=52:54:00:12:34:58 \ 2602 -netdev socket,id=n3,mcast=230.0.0.1:1234 2603@end example 2604 2605Example (User Mode Linux compat.): 2606@example 2607# launch QEMU instance (note mcast address selected is UML's default) 2608@value{qemu_system} linux.img \ 2609 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2610 -netdev socket,id=n1,mcast=239.192.168.1:1102 2611# launch UML 2612/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2613@end example 2614 2615Example (send packets from host's 1.2.3.4): 2616@example 2617@value{qemu_system} linux.img \ 2618 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2619 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2620@end example 2621 2622@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}] 2623Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a 2624popular protocol to transport Ethernet (and other Layer 2) data frames between 2625two systems. It is present in routers, firewalls and the Linux kernel 2626(from version 3.3 onwards). 2627 2628This transport allows a VM to communicate to another VM, router or firewall directly. 2629 2630@table @option 2631@item src=@var{srcaddr} 2632 source address (mandatory) 2633@item dst=@var{dstaddr} 2634 destination address (mandatory) 2635@item udp 2636 select udp encapsulation (default is ip). 2637@item srcport=@var{srcport} 2638 source udp port. 2639@item dstport=@var{dstport} 2640 destination udp port. 2641@item ipv6 2642 force v6, otherwise defaults to v4. 2643@item rxcookie=@var{rxcookie} 2644@itemx txcookie=@var{txcookie} 2645 Cookies are a weak form of security in the l2tpv3 specification. 2646Their function is mostly to prevent misconfiguration. By default they are 32 2647bit. 2648@item cookie64 2649 Set cookie size to 64 bit instead of the default 32 2650@item counter=off 2651 Force a 'cut-down' L2TPv3 with no counter as in 2652draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2653@item pincounter=on 2654 Work around broken counter handling in peer. This may also help on 2655networks which have packet reorder. 2656@item offset=@var{offset} 2657 Add an extra offset between header and data 2658@end table 2659 2660For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2661on the remote Linux host 1.2.3.4: 2662@example 2663# Setup tunnel on linux host using raw ip as encapsulation 2664# on 1.2.3.4 2665ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2666 encap udp udp_sport 16384 udp_dport 16384 2667ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2668 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2669ifconfig vmtunnel0 mtu 1500 2670ifconfig vmtunnel0 up 2671brctl addif br-lan vmtunnel0 2672 2673 2674# on 4.3.2.1 2675# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2676 2677@value{qemu_system} linux.img -device e1000,netdev=n1 \ 2678 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2679 2680@end example 2681 2682@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2683Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and 2684listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2685and MODE @var{octalmode} to change default ownership and permissions for 2686communication port. This option is only available if QEMU has been compiled 2687with vde support enabled. 2688 2689Example: 2690@example 2691# launch vde switch 2692vde_switch -F -sock /tmp/myswitch 2693# launch QEMU instance 2694@value{qemu_system} linux.img -nic vde,sock=/tmp/myswitch 2695@end example 2696 2697@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2698 2699Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2700be a unix domain socket backed one. The vhost-user uses a specifically defined 2701protocol to pass vhost ioctl replacement messages to an application on the other 2702end of the socket. On non-MSIX guests, the feature can be forced with 2703@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2704be created for multiqueue vhost-user. 2705 2706Example: 2707@example 2708qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2709 -numa node,memdev=mem \ 2710 -chardev socket,id=chr0,path=/path/to/socket \ 2711 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2712 -device virtio-net-pci,netdev=net0 2713@end example 2714 2715@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}] 2716 2717Create a hub port on the emulated hub with ID @var{hubid}. 2718 2719The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a 2720single netdev. Alternatively, you can also connect the hubport to another 2721netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option. 2722 2723@item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2724@findex -net 2725Legacy option to configure or create an on-board (or machine default) Network 2726Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. 2727the default hub), or to the netdev @var{nd}. 2728The NIC is an e1000 by default on the PC target. Optionally, the MAC address 2729can be changed to @var{mac}, the device address set to @var{addr} (PCI cards 2730only), and a @var{name} can be assigned for use in monitor commands. 2731Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2732that the card should have; this option currently only affects virtio cards; set 2733@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2734NIC is created. QEMU can emulate several different models of network card. 2735Use @code{-net nic,model=help} for a list of available devices for your target. 2736 2737@item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}] 2738Configure a host network backend (with the options corresponding to the same 2739@option{-netdev} option) and connect it to the emulated hub 0 (the default 2740hub). Use @var{name} to specify the name of the hub port. 2741ETEXI 2742 2743STEXI 2744@end table 2745ETEXI 2746DEFHEADING() 2747 2748DEFHEADING(Character device options:) 2749 2750DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2751 "-chardev help\n" 2752 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2753 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2754 " [,server][,nowait][,telnet][,websocket][,reconnect=seconds][,mux=on|off]\n" 2755 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID][,tls-authz=ID] (tcp)\n" 2756 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,websocket][,reconnect=seconds]\n" 2757 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2758 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2759 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2760 " [,logfile=PATH][,logappend=on|off]\n" 2761 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2762 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2763 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2764 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2765 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2766 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2767#ifdef _WIN32 2768 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2769 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2770#else 2771 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2772 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2773#endif 2774#ifdef CONFIG_BRLAPI 2775 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2776#endif 2777#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2778 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2779 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2780 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2781#endif 2782#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2783 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2784 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2785#endif 2786#if defined(CONFIG_SPICE) 2787 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2788 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2789#endif 2790 , QEMU_ARCH_ALL 2791) 2792 2793STEXI 2794 2795The general form of a character device option is: 2796@table @option 2797@item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}] 2798@findex -chardev 2799Backend is one of: 2800@option{null}, 2801@option{socket}, 2802@option{udp}, 2803@option{msmouse}, 2804@option{vc}, 2805@option{ringbuf}, 2806@option{file}, 2807@option{pipe}, 2808@option{console}, 2809@option{serial}, 2810@option{pty}, 2811@option{stdio}, 2812@option{braille}, 2813@option{tty}, 2814@option{parallel}, 2815@option{parport}, 2816@option{spicevmc}, 2817@option{spiceport}. 2818The specific backend will determine the applicable options. 2819 2820Use @code{-chardev help} to print all available chardev backend types. 2821 2822All devices must have an id, which can be any string up to 127 characters long. 2823It is used to uniquely identify this device in other command line directives. 2824 2825A character device may be used in multiplexing mode by multiple front-ends. 2826Specify @option{mux=on} to enable this mode. 2827A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2828backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2829If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2830create a multiplexer with your specified ID, and you can then configure multiple 2831front ends to use that chardev ID for their input/output. Up to four different 2832front ends can be connected to a single multiplexed chardev. (Without 2833multiplexing enabled, a chardev can only be used by a single front end.) 2834For instance you could use this to allow a single stdio chardev to be used by 2835two serial ports and the QEMU monitor: 2836 2837@example 2838-chardev stdio,mux=on,id=char0 \ 2839-mon chardev=char0,mode=readline \ 2840-serial chardev:char0 \ 2841-serial chardev:char0 2842@end example 2843 2844You can have more than one multiplexer in a system configuration; for instance 2845you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2846multiplexed between the QEMU monitor and a parallel port: 2847 2848@example 2849-chardev stdio,mux=on,id=char0 \ 2850-mon chardev=char0,mode=readline \ 2851-parallel chardev:char0 \ 2852-chardev tcp,...,mux=on,id=char1 \ 2853-serial chardev:char1 \ 2854-serial chardev:char1 2855@end example 2856 2857When you're using a multiplexed character device, some escape sequences are 2858interpreted in the input. @xref{mux_keys, Keys in the character backend 2859multiplexer}. 2860 2861Note that some other command line options may implicitly create multiplexed 2862character backends; for instance @option{-serial mon:stdio} creates a 2863multiplexed stdio backend connected to the serial port and the QEMU monitor, 2864and @option{-nographic} also multiplexes the console and the monitor to 2865stdio. 2866 2867There is currently no support for multiplexing in the other direction 2868(where a single QEMU front end takes input and output from multiple chardevs). 2869 2870Every backend supports the @option{logfile} option, which supplies the path 2871to a file to record all data transmitted via the backend. The @option{logappend} 2872option controls whether the log file will be truncated or appended to when 2873opened. 2874 2875@end table 2876 2877The available backends are: 2878 2879@table @option 2880@item -chardev null,id=@var{id} 2881A void device. This device will not emit any data, and will drop any data it 2882receives. The null backend does not take any options. 2883 2884@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,websocket][,reconnect=@var{seconds}][,tls-creds=@var{id}][,tls-authz=@var{id}] 2885 2886Create a two-way stream socket, which can be either a TCP or a unix socket. A 2887unix socket will be created if @option{path} is specified. Behaviour is 2888undefined if TCP options are specified for a unix socket. 2889 2890@option{server} specifies that the socket shall be a listening socket. 2891 2892@option{nowait} specifies that QEMU should not block waiting for a client to 2893connect to a listening socket. 2894 2895@option{telnet} specifies that traffic on the socket should interpret telnet 2896escape sequences. 2897 2898@option{websocket} specifies that the socket uses WebSocket protocol for 2899communication. 2900 2901@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2902the remote end goes away. qemu will delay this many seconds and then attempt 2903to reconnect. Zero disables reconnecting, and is the default. 2904 2905@option{tls-creds} requests enablement of the TLS protocol for encryption, 2906and specifies the id of the TLS credentials to use for the handshake. The 2907credentials must be previously created with the @option{-object tls-creds} 2908argument. 2909 2910@option{tls-auth} provides the ID of the QAuthZ authorization object against 2911which the client's x509 distinguished name will be validated. This object is 2912only resolved at time of use, so can be deleted and recreated on the fly 2913while the chardev server is active. If missing, it will default to denying 2914access. 2915 2916TCP and unix socket options are given below: 2917 2918@table @option 2919 2920@item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay] 2921 2922@option{host} for a listening socket specifies the local address to be bound. 2923For a connecting socket species the remote host to connect to. @option{host} is 2924optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2925 2926@option{port} for a listening socket specifies the local port to be bound. For a 2927connecting socket specifies the port on the remote host to connect to. 2928@option{port} can be given as either a port number or a service name. 2929@option{port} is required. 2930 2931@option{to} is only relevant to listening sockets. If it is specified, and 2932@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2933to and including @option{to} until it succeeds. @option{to} must be specified 2934as a port number. 2935 2936@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2937If neither is specified the socket may use either protocol. 2938 2939@option{nodelay} disables the Nagle algorithm. 2940 2941@item unix options: path=@var{path} 2942 2943@option{path} specifies the local path of the unix socket. @option{path} is 2944required. 2945 2946@end table 2947 2948@item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6] 2949 2950Sends all traffic from the guest to a remote host over UDP. 2951 2952@option{host} specifies the remote host to connect to. If not specified it 2953defaults to @code{localhost}. 2954 2955@option{port} specifies the port on the remote host to connect to. @option{port} 2956is required. 2957 2958@option{localaddr} specifies the local address to bind to. If not specified it 2959defaults to @code{0.0.0.0}. 2960 2961@option{localport} specifies the local port to bind to. If not specified any 2962available local port will be used. 2963 2964@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2965If neither is specified the device may use either protocol. 2966 2967@item -chardev msmouse,id=@var{id} 2968 2969Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2970take any options. 2971 2972@item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]] 2973 2974Connect to a QEMU text console. @option{vc} may optionally be given a specific 2975size. 2976 2977@option{width} and @option{height} specify the width and height respectively of 2978the console, in pixels. 2979 2980@option{cols} and @option{rows} specify that the console be sized to fit a text 2981console with the given dimensions. 2982 2983@item -chardev ringbuf,id=@var{id}[,size=@var{size}] 2984 2985Create a ring buffer with fixed size @option{size}. 2986@var{size} must be a power of two and defaults to @code{64K}. 2987 2988@item -chardev file,id=@var{id},path=@var{path} 2989 2990Log all traffic received from the guest to a file. 2991 2992@option{path} specifies the path of the file to be opened. This file will be 2993created if it does not already exist, and overwritten if it does. @option{path} 2994is required. 2995 2996@item -chardev pipe,id=@var{id},path=@var{path} 2997 2998Create a two-way connection to the guest. The behaviour differs slightly between 2999Windows hosts and other hosts: 3000 3001On Windows, a single duplex pipe will be created at 3002@file{\\.pipe\@option{path}}. 3003 3004On other hosts, 2 pipes will be created called @file{@option{path}.in} and 3005@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 3006received by the guest. Data written by the guest can be read from 3007@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 3008be present. 3009 3010@option{path} forms part of the pipe path as described above. @option{path} is 3011required. 3012 3013@item -chardev console,id=@var{id} 3014 3015Send traffic from the guest to QEMU's standard output. @option{console} does not 3016take any options. 3017 3018@option{console} is only available on Windows hosts. 3019 3020@item -chardev serial,id=@var{id},path=@option{path} 3021 3022Send traffic from the guest to a serial device on the host. 3023 3024On Unix hosts serial will actually accept any tty device, 3025not only serial lines. 3026 3027@option{path} specifies the name of the serial device to open. 3028 3029@item -chardev pty,id=@var{id} 3030 3031Create a new pseudo-terminal on the host and connect to it. @option{pty} does 3032not take any options. 3033 3034@option{pty} is not available on Windows hosts. 3035 3036@item -chardev stdio,id=@var{id}[,signal=on|off] 3037Connect to standard input and standard output of the QEMU process. 3038 3039@option{signal} controls if signals are enabled on the terminal, that includes 3040exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 3041default, use @option{signal=off} to disable it. 3042 3043@item -chardev braille,id=@var{id} 3044 3045Connect to a local BrlAPI server. @option{braille} does not take any options. 3046 3047@item -chardev tty,id=@var{id},path=@var{path} 3048 3049@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 3050DragonFlyBSD hosts. It is an alias for @option{serial}. 3051 3052@option{path} specifies the path to the tty. @option{path} is required. 3053 3054@item -chardev parallel,id=@var{id},path=@var{path} 3055@itemx -chardev parport,id=@var{id},path=@var{path} 3056 3057@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 3058 3059Connect to a local parallel port. 3060 3061@option{path} specifies the path to the parallel port device. @option{path} is 3062required. 3063 3064@item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name} 3065 3066@option{spicevmc} is only available when spice support is built in. 3067 3068@option{debug} debug level for spicevmc 3069 3070@option{name} name of spice channel to connect to 3071 3072Connect to a spice virtual machine channel, such as vdiport. 3073 3074@item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name} 3075 3076@option{spiceport} is only available when spice support is built in. 3077 3078@option{debug} debug level for spicevmc 3079 3080@option{name} name of spice port to connect to 3081 3082Connect to a spice port, allowing a Spice client to handle the traffic 3083identified by a name (preferably a fqdn). 3084ETEXI 3085 3086STEXI 3087@end table 3088ETEXI 3089DEFHEADING() 3090 3091DEFHEADING(Bluetooth(R) options:) 3092STEXI 3093@table @option 3094ETEXI 3095 3096DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 3097 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 3098 "-bt hci,host[:id]\n" \ 3099 " use host's HCI with the given name\n" \ 3100 "-bt hci[,vlan=n]\n" \ 3101 " emulate a standard HCI in virtual scatternet 'n'\n" \ 3102 "-bt vhci[,vlan=n]\n" \ 3103 " add host computer to virtual scatternet 'n' using VHCI\n" \ 3104 "-bt device:dev[,vlan=n]\n" \ 3105 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 3106 QEMU_ARCH_ALL) 3107STEXI 3108@item -bt hci[...] 3109@findex -bt 3110Defines the function of the corresponding Bluetooth HCI. -bt options 3111are matched with the HCIs present in the chosen machine type. For 3112example when emulating a machine with only one HCI built into it, only 3113the first @code{-bt hci[...]} option is valid and defines the HCI's 3114logic. The Transport Layer is decided by the machine type. Currently 3115the machines @code{n800} and @code{n810} have one HCI and all other 3116machines have none. 3117 3118Note: This option and the whole bluetooth subsystem is considered as deprecated. 3119If you still use it, please send a mail to @email{qemu-devel@@nongnu.org} where 3120you describe your usecase. 3121 3122@anchor{bt-hcis} 3123The following three types are recognized: 3124 3125@table @option 3126@item -bt hci,null 3127(default) The corresponding Bluetooth HCI assumes no internal logic 3128and will not respond to any HCI commands or emit events. 3129 3130@item -bt hci,host[:@var{id}] 3131(@code{bluez} only) The corresponding HCI passes commands / events 3132to / from the physical HCI identified by the name @var{id} (default: 3133@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 3134capable systems like Linux. 3135 3136@item -bt hci[,vlan=@var{n}] 3137Add a virtual, standard HCI that will participate in the Bluetooth 3138scatternet @var{n} (default @code{0}). Similarly to @option{-net} 3139VLANs, devices inside a bluetooth network @var{n} can only communicate 3140with other devices in the same network (scatternet). 3141@end table 3142 3143@item -bt vhci[,vlan=@var{n}] 3144(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 3145to the host bluetooth stack instead of to the emulated target. This 3146allows the host and target machines to participate in a common scatternet 3147and communicate. Requires the Linux @code{vhci} driver installed. Can 3148be used as following: 3149 3150@example 3151@value{qemu_system} [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 3152@end example 3153 3154@item -bt device:@var{dev}[,vlan=@var{n}] 3155Emulate a bluetooth device @var{dev} and place it in network @var{n} 3156(default @code{0}). QEMU can only emulate one type of bluetooth devices 3157currently: 3158 3159@table @option 3160@item keyboard 3161Virtual wireless keyboard implementing the HIDP bluetooth profile. 3162@end table 3163ETEXI 3164 3165STEXI 3166@end table 3167ETEXI 3168DEFHEADING() 3169 3170#ifdef CONFIG_TPM 3171DEFHEADING(TPM device options:) 3172 3173DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 3174 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 3175 " use path to provide path to a character device; default is /dev/tpm0\n" 3176 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 3177 " not provided it will be searched for in /sys/class/misc/tpm?/device\n" 3178 "-tpmdev emulator,id=id,chardev=dev\n" 3179 " configure the TPM device using chardev backend\n", 3180 QEMU_ARCH_ALL) 3181STEXI 3182 3183The general form of a TPM device option is: 3184@table @option 3185 3186@item -tpmdev @var{backend},id=@var{id}[,@var{options}] 3187@findex -tpmdev 3188 3189The specific backend type will determine the applicable options. 3190The @code{-tpmdev} option creates the TPM backend and requires a 3191@code{-device} option that specifies the TPM frontend interface model. 3192 3193Use @code{-tpmdev help} to print all available TPM backend types. 3194 3195@end table 3196 3197The available backends are: 3198 3199@table @option 3200 3201@item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path} 3202 3203(Linux-host only) Enable access to the host's TPM using the passthrough 3204driver. 3205 3206@option{path} specifies the path to the host's TPM device, i.e., on 3207a Linux host this would be @code{/dev/tpm0}. 3208@option{path} is optional and by default @code{/dev/tpm0} is used. 3209 3210@option{cancel-path} specifies the path to the host TPM device's sysfs 3211entry allowing for cancellation of an ongoing TPM command. 3212@option{cancel-path} is optional and by default QEMU will search for the 3213sysfs entry to use. 3214 3215Some notes about using the host's TPM with the passthrough driver: 3216 3217The TPM device accessed by the passthrough driver must not be 3218used by any other application on the host. 3219 3220Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 3221the VM's firmware (BIOS/UEFI) will not be able to initialize the 3222TPM again and may therefore not show a TPM-specific menu that would 3223otherwise allow the user to configure the TPM, e.g., allow the user to 3224enable/disable or activate/deactivate the TPM. 3225Further, if TPM ownership is released from within a VM then the host's TPM 3226will get disabled and deactivated. To enable and activate the 3227TPM again afterwards, the host has to be rebooted and the user is 3228required to enter the firmware's menu to enable and activate the TPM. 3229If the TPM is left disabled and/or deactivated most TPM commands will fail. 3230 3231To create a passthrough TPM use the following two options: 3232@example 3233-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 3234@end example 3235Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 3236@code{tpmdev=tpm0} in the device option. 3237 3238@item -tpmdev emulator,id=@var{id},chardev=@var{dev} 3239 3240(Linux-host only) Enable access to a TPM emulator using Unix domain socket based 3241chardev backend. 3242 3243@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server. 3244 3245To create a TPM emulator backend device with chardev socket backend: 3246@example 3247 3248-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0 3249 3250@end example 3251 3252ETEXI 3253 3254STEXI 3255@end table 3256ETEXI 3257DEFHEADING() 3258 3259#endif 3260 3261DEFHEADING(Linux/Multiboot boot specific:) 3262STEXI 3263 3264When using these options, you can use a given Linux or Multiboot 3265kernel without installing it in the disk image. It can be useful 3266for easier testing of various kernels. 3267 3268@table @option 3269ETEXI 3270 3271DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 3272 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 3273STEXI 3274@item -kernel @var{bzImage} 3275@findex -kernel 3276Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 3277or in multiboot format. 3278ETEXI 3279 3280DEF("append", HAS_ARG, QEMU_OPTION_append, \ 3281 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 3282STEXI 3283@item -append @var{cmdline} 3284@findex -append 3285Use @var{cmdline} as kernel command line 3286ETEXI 3287 3288DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 3289 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 3290STEXI 3291@item -initrd @var{file} 3292@findex -initrd 3293Use @var{file} as initial ram disk. 3294 3295@item -initrd "@var{file1} arg=foo,@var{file2}" 3296 3297This syntax is only available with multiboot. 3298 3299Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 3300first module. 3301ETEXI 3302 3303DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 3304 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 3305STEXI 3306@item -dtb @var{file} 3307@findex -dtb 3308Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 3309on boot. 3310ETEXI 3311 3312STEXI 3313@end table 3314ETEXI 3315DEFHEADING() 3316 3317DEFHEADING(Debug/Expert options:) 3318STEXI 3319@table @option 3320ETEXI 3321 3322DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 3323 "-fw_cfg [name=]<name>,file=<file>\n" 3324 " add named fw_cfg entry with contents from file\n" 3325 "-fw_cfg [name=]<name>,string=<str>\n" 3326 " add named fw_cfg entry with contents from string\n", 3327 QEMU_ARCH_ALL) 3328STEXI 3329 3330@item -fw_cfg [name=]@var{name},file=@var{file} 3331@findex -fw_cfg 3332Add named fw_cfg entry with contents from file @var{file}. 3333 3334@item -fw_cfg [name=]@var{name},string=@var{str} 3335Add named fw_cfg entry with contents from string @var{str}. 3336 3337The terminating NUL character of the contents of @var{str} will not be 3338included as part of the fw_cfg item data. To insert contents with 3339embedded NUL characters, you have to use the @var{file} parameter. 3340 3341The fw_cfg entries are passed by QEMU through to the guest. 3342 3343Example: 3344@example 3345 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 3346@end example 3347creates an fw_cfg entry named opt/com.mycompany/blob with contents 3348from ./my_blob.bin. 3349 3350ETEXI 3351 3352DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 3353 "-serial dev redirect the serial port to char device 'dev'\n", 3354 QEMU_ARCH_ALL) 3355STEXI 3356@item -serial @var{dev} 3357@findex -serial 3358Redirect the virtual serial port to host character device 3359@var{dev}. The default device is @code{vc} in graphical mode and 3360@code{stdio} in non graphical mode. 3361 3362This option can be used several times to simulate up to 4 serial 3363ports. 3364 3365Use @code{-serial none} to disable all serial ports. 3366 3367Available character devices are: 3368@table @option 3369@item vc[:@var{W}x@var{H}] 3370Virtual console. Optionally, a width and height can be given in pixel with 3371@example 3372vc:800x600 3373@end example 3374It is also possible to specify width or height in characters: 3375@example 3376vc:80Cx24C 3377@end example 3378@item pty 3379[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3380@item none 3381No device is allocated. 3382@item null 3383void device 3384@item chardev:@var{id} 3385Use a named character device defined with the @code{-chardev} option. 3386@item /dev/XXX 3387[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3388parameters are set according to the emulated ones. 3389@item /dev/parport@var{N} 3390[Linux only, parallel port only] Use host parallel port 3391@var{N}. Currently SPP and EPP parallel port features can be used. 3392@item file:@var{filename} 3393Write output to @var{filename}. No character can be read. 3394@item stdio 3395[Unix only] standard input/output 3396@item pipe:@var{filename} 3397name pipe @var{filename} 3398@item COM@var{n} 3399[Windows only] Use host serial port @var{n} 3400@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3401This implements UDP Net Console. 3402When @var{remote_host} or @var{src_ip} are not specified 3403they default to @code{0.0.0.0}. 3404When not using a specified @var{src_port} a random port is automatically chosen. 3405 3406If you just want a simple readonly console you can use @code{netcat} or 3407@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3408@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3409will appear in the netconsole session. 3410 3411If you plan to send characters back via netconsole or you want to stop 3412and start QEMU a lot of times, you should have QEMU use the same 3413source port each time by using something like @code{-serial 3414udp::4555@@:4556} to QEMU. Another approach is to use a patched 3415version of netcat which can listen to a TCP port and send and receive 3416characters via udp. If you have a patched version of netcat which 3417activates telnet remote echo and single char transfer, then you can 3418use the following options to set up a netcat redirector to allow 3419telnet on port 5555 to access the QEMU port. 3420@table @code 3421@item QEMU Options: 3422-serial udp::4555@@:4556 3423@item netcat options: 3424-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3425@item telnet options: 3426localhost 5555 3427@end table 3428 3429@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3430The TCP Net Console has two modes of operation. It can send the serial 3431I/O to a location or wait for a connection from a location. By default 3432the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3433the @var{server} option QEMU will wait for a client socket application 3434to connect to the port before continuing, unless the @code{nowait} 3435option was specified. The @code{nodelay} option disables the Nagle buffering 3436algorithm. The @code{reconnect} option only applies if @var{noserver} is 3437set, if the connection goes down it will attempt to reconnect at the 3438given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3439one TCP connection at a time is accepted. You can use @code{telnet} to 3440connect to the corresponding character device. 3441@table @code 3442@item Example to send tcp console to 192.168.0.2 port 4444 3443-serial tcp:192.168.0.2:4444 3444@item Example to listen and wait on port 4444 for connection 3445-serial tcp::4444,server 3446@item Example to not wait and listen on ip 192.168.0.100 port 4444 3447-serial tcp:192.168.0.100:4444,server,nowait 3448@end table 3449 3450@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3451The telnet protocol is used instead of raw tcp sockets. The options 3452work the same as if you had specified @code{-serial tcp}. The 3453difference is that the port acts like a telnet server or client using 3454telnet option negotiation. This will also allow you to send the 3455MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3456sequence. Typically in unix telnet you do it with Control-] and then 3457type "send break" followed by pressing the enter key. 3458 3459@item websocket:@var{host}:@var{port},server[,nowait][,nodelay] 3460The WebSocket protocol is used instead of raw tcp socket. The port acts as 3461a WebSocket server. Client mode is not supported. 3462 3463@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3464A unix domain socket is used instead of a tcp socket. The option works the 3465same as if you had specified @code{-serial tcp} except the unix domain socket 3466@var{path} is used for connections. 3467 3468@item mon:@var{dev_string} 3469This is a special option to allow the monitor to be multiplexed onto 3470another serial port. The monitor is accessed with key sequence of 3471@key{Control-a} and then pressing @key{c}. 3472@var{dev_string} should be any one of the serial devices specified 3473above. An example to multiplex the monitor onto a telnet server 3474listening on port 4444 would be: 3475@table @code 3476@item -serial mon:telnet::4444,server,nowait 3477@end table 3478When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3479QEMU any more but will be passed to the guest instead. 3480 3481@item braille 3482Braille device. This will use BrlAPI to display the braille output on a real 3483or fake device. 3484 3485@item msmouse 3486Three button serial mouse. Configure the guest to use Microsoft protocol. 3487@end table 3488ETEXI 3489 3490DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3491 "-parallel dev redirect the parallel port to char device 'dev'\n", 3492 QEMU_ARCH_ALL) 3493STEXI 3494@item -parallel @var{dev} 3495@findex -parallel 3496Redirect the virtual parallel port to host device @var{dev} (same 3497devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3498be used to use hardware devices connected on the corresponding host 3499parallel port. 3500 3501This option can be used several times to simulate up to 3 parallel 3502ports. 3503 3504Use @code{-parallel none} to disable all parallel ports. 3505ETEXI 3506 3507DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3508 "-monitor dev redirect the monitor to char device 'dev'\n", 3509 QEMU_ARCH_ALL) 3510STEXI 3511@item -monitor @var{dev} 3512@findex -monitor 3513Redirect the monitor to host device @var{dev} (same devices as the 3514serial port). 3515The default device is @code{vc} in graphical mode and @code{stdio} in 3516non graphical mode. 3517Use @code{-monitor none} to disable the default monitor. 3518ETEXI 3519DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3520 "-qmp dev like -monitor but opens in 'control' mode\n", 3521 QEMU_ARCH_ALL) 3522STEXI 3523@item -qmp @var{dev} 3524@findex -qmp 3525Like -monitor but opens in 'control' mode. 3526ETEXI 3527DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3528 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3529 QEMU_ARCH_ALL) 3530STEXI 3531@item -qmp-pretty @var{dev} 3532@findex -qmp-pretty 3533Like -qmp but uses pretty JSON formatting. 3534ETEXI 3535 3536DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3537 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL) 3538STEXI 3539@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]] 3540@findex -mon 3541Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing 3542easing human reading and debugging. 3543ETEXI 3544 3545DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3546 "-debugcon dev redirect the debug console to char device 'dev'\n", 3547 QEMU_ARCH_ALL) 3548STEXI 3549@item -debugcon @var{dev} 3550@findex -debugcon 3551Redirect the debug console to host device @var{dev} (same devices as the 3552serial port). The debug console is an I/O port which is typically port 35530xe9; writing to that I/O port sends output to this device. 3554The default device is @code{vc} in graphical mode and @code{stdio} in 3555non graphical mode. 3556ETEXI 3557 3558DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3559 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3560STEXI 3561@item -pidfile @var{file} 3562@findex -pidfile 3563Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3564from a script. 3565ETEXI 3566 3567DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3568 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3569STEXI 3570@item -singlestep 3571@findex -singlestep 3572Run the emulation in single step mode. 3573ETEXI 3574 3575DEF("preconfig", 0, QEMU_OPTION_preconfig, \ 3576 "--preconfig pause QEMU before machine is initialized (experimental)\n", 3577 QEMU_ARCH_ALL) 3578STEXI 3579@item --preconfig 3580@findex --preconfig 3581Pause QEMU for interactive configuration before the machine is created, 3582which allows querying and configuring properties that will affect 3583machine initialization. Use QMP command 'x-exit-preconfig' to exit 3584the preconfig state and move to the next state (i.e. run guest if -S 3585isn't used or pause the second time if -S is used). This option is 3586experimental. 3587ETEXI 3588 3589DEF("S", 0, QEMU_OPTION_S, \ 3590 "-S freeze CPU at startup (use 'c' to start execution)\n", 3591 QEMU_ARCH_ALL) 3592STEXI 3593@item -S 3594@findex -S 3595Do not start CPU at startup (you must type 'c' in the monitor). 3596ETEXI 3597 3598DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3599 "-realtime [mlock=on|off]\n" 3600 " run qemu with realtime features\n" 3601 " mlock=on|off controls mlock support (default: on)\n", 3602 QEMU_ARCH_ALL) 3603STEXI 3604@item -realtime mlock=on|off 3605@findex -realtime 3606Run qemu with realtime features. 3607mlocking qemu and guest memory can be enabled via @option{mlock=on} 3608(enabled by default). 3609ETEXI 3610 3611DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, 3612 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" 3613 " run qemu with overcommit hints\n" 3614 " mem-lock=on|off controls memory lock support (default: off)\n" 3615 " cpu-pm=on|off controls cpu power management (default: off)\n", 3616 QEMU_ARCH_ALL) 3617STEXI 3618@item -overcommit mem-lock=on|off 3619@item -overcommit cpu-pm=on|off 3620@findex -overcommit 3621Run qemu with hints about host resource overcommit. The default is 3622to assume that host overcommits all resources. 3623 3624Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled 3625by default). This works when host memory is not overcommitted and reduces the 3626worst-case latency for guest. This is equivalent to @option{realtime}. 3627 3628Guest ability to manage power state of host cpus (increasing latency for other 3629processes on the same host cpu, but decreasing latency for guest) can be 3630enabled via @option{cpu-pm=on} (disabled by default). This works best when 3631host CPU is not overcommitted. When used, host estimates of CPU cycle and power 3632utilization will be incorrect, not taking into account guest idle time. 3633ETEXI 3634 3635DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3636 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3637STEXI 3638@item -gdb @var{dev} 3639@findex -gdb 3640Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3641connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3642stdio are reasonable use case. The latter is allowing to start QEMU from 3643within gdb and establish the connection via a pipe: 3644@example 3645(gdb) target remote | exec @value{qemu_system} -gdb stdio ... 3646@end example 3647ETEXI 3648 3649DEF("s", 0, QEMU_OPTION_s, \ 3650 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3651 QEMU_ARCH_ALL) 3652STEXI 3653@item -s 3654@findex -s 3655Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3656(@pxref{gdb_usage}). 3657ETEXI 3658 3659DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3660 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3661 QEMU_ARCH_ALL) 3662STEXI 3663@item -d @var{item1}[,...] 3664@findex -d 3665Enable logging of specified items. Use '-d help' for a list of log items. 3666ETEXI 3667 3668DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3669 "-D logfile output log to logfile (default stderr)\n", 3670 QEMU_ARCH_ALL) 3671STEXI 3672@item -D @var{logfile} 3673@findex -D 3674Output log in @var{logfile} instead of to stderr 3675ETEXI 3676 3677DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3678 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3679 QEMU_ARCH_ALL) 3680STEXI 3681@item -dfilter @var{range1}[,...] 3682@findex -dfilter 3683Filter debug output to that relevant to a range of target addresses. The filter 3684spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3685@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3686addresses and sizes required. For example: 3687@example 3688 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3689@end example 3690Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3691the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3692block starting at 0xffffffc00005f000. 3693ETEXI 3694 3695DEF("seed", HAS_ARG, QEMU_OPTION_seed, \ 3696 "-seed number seed the pseudo-random number generator\n", 3697 QEMU_ARCH_ALL) 3698STEXI 3699@item -seed @var{number} 3700@findex -seed 3701Force the guest to use a deterministic pseudo-random number generator, seeded 3702with @var{number}. This does not affect crypto routines within the host. 3703ETEXI 3704 3705DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3706 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3707 QEMU_ARCH_ALL) 3708STEXI 3709@item -L @var{path} 3710@findex -L 3711Set the directory for the BIOS, VGA BIOS and keymaps. 3712 3713To list all the data directories, use @code{-L help}. 3714ETEXI 3715 3716DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3717 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3718STEXI 3719@item -bios @var{file} 3720@findex -bios 3721Set the filename for the BIOS. 3722ETEXI 3723 3724DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3725 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3726STEXI 3727@item -enable-kvm 3728@findex -enable-kvm 3729Enable KVM full virtualization support. This option is only available 3730if KVM support is enabled when compiling. 3731ETEXI 3732 3733DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3734 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3735DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3736 "-xen-attach attach to existing xen domain\n" 3737 " libxl will use this when starting QEMU\n", 3738 QEMU_ARCH_ALL) 3739DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict, 3740 "-xen-domid-restrict restrict set of available xen operations\n" 3741 " to specified domain id. (Does not affect\n" 3742 " xenpv machine type).\n", 3743 QEMU_ARCH_ALL) 3744STEXI 3745@item -xen-domid @var{id} 3746@findex -xen-domid 3747Specify xen guest domain @var{id} (XEN only). 3748@item -xen-attach 3749@findex -xen-attach 3750Attach to existing xen domain. 3751libxl will use this when starting QEMU (XEN only). 3752@findex -xen-domid-restrict 3753Restrict set of available xen operations to specified domain id (XEN only). 3754ETEXI 3755 3756DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3757 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3758STEXI 3759@item -no-reboot 3760@findex -no-reboot 3761Exit instead of rebooting. 3762ETEXI 3763 3764DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3765 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3766STEXI 3767@item -no-shutdown 3768@findex -no-shutdown 3769Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3770This allows for instance switching to monitor to commit changes to the 3771disk image. 3772ETEXI 3773 3774DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3775 "-loadvm [tag|id]\n" \ 3776 " start right away with a saved state (loadvm in monitor)\n", 3777 QEMU_ARCH_ALL) 3778STEXI 3779@item -loadvm @var{file} 3780@findex -loadvm 3781Start right away with a saved state (@code{loadvm} in monitor) 3782ETEXI 3783 3784#ifndef _WIN32 3785DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3786 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3787#endif 3788STEXI 3789@item -daemonize 3790@findex -daemonize 3791Daemonize the QEMU process after initialization. QEMU will not detach from 3792standard IO until it is ready to receive connections on any of its devices. 3793This option is a useful way for external programs to launch QEMU without having 3794to cope with initialization race conditions. 3795ETEXI 3796 3797DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3798 "-option-rom rom load a file, rom, into the option ROM space\n", 3799 QEMU_ARCH_ALL) 3800STEXI 3801@item -option-rom @var{file} 3802@findex -option-rom 3803Load the contents of @var{file} as an option ROM. 3804This option is useful to load things like EtherBoot. 3805ETEXI 3806 3807DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3808 "-rtc [base=utc|localtime|<datetime>][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3809 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3810 QEMU_ARCH_ALL) 3811 3812STEXI 3813 3814@item -rtc [base=utc|localtime|@var{datetime}][,clock=host|rt|vm][,driftfix=none|slew] 3815@findex -rtc 3816Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3817UTC or local time, respectively. @code{localtime} is required for correct date in 3818MS-DOS or Windows. To start at a specific point in time, provide @var{datetime} in the 3819format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3820 3821By default the RTC is driven by the host system time. This allows using of the 3822RTC as accurate reference clock inside the guest, specifically if the host 3823time is smoothly following an accurate external reference clock, e.g. via NTP. 3824If you want to isolate the guest time from the host, you can set @option{clock} 3825to @code{rt} instead, which provides a host monotonic clock if host support it. 3826To even prevent the RTC from progressing during suspension, you can set @option{clock} 3827to @code{vm} (virtual clock). @samp{clock=vm} is recommended especially in 3828icount mode in order to preserve determinism; however, note that in icount mode 3829the speed of the virtual clock is variable and can in general differ from the 3830host clock. 3831 3832Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3833specifically with Windows' ACPI HAL. This option will try to figure out how 3834many timer interrupts were not processed by the Windows guest and will 3835re-inject them. 3836ETEXI 3837 3838DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3839 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3840 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3841 " instruction, enable aligning the host and virtual clocks\n" \ 3842 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3843STEXI 3844@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3845@findex -icount 3846Enable virtual instruction counter. The virtual cpu will execute one 3847instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3848then the virtual cpu speed will be automatically adjusted to keep virtual 3849time within a few seconds of real time. 3850 3851When the virtual cpu is sleeping, the virtual time will advance at default 3852speed unless @option{sleep=on|off} is specified. 3853With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3854instantly whenever the virtual cpu goes to sleep mode and will not advance 3855if no timer is enabled. This behavior give deterministic execution times from 3856the guest point of view. 3857 3858Note that while this option can give deterministic behavior, it does not 3859provide cycle accurate emulation. Modern CPUs contain superscalar out of 3860order cores with complex cache hierarchies. The number of instructions 3861executed often has little or no correlation with actual performance. 3862 3863@option{align=on} will activate the delay algorithm which will try 3864to synchronise the host clock and the virtual clock. The goal is to 3865have a guest running at the real frequency imposed by the shift option. 3866Whenever the guest clock is behind the host clock and if 3867@option{align=on} is specified then we print a message to the user 3868to inform about the delay. 3869Currently this option does not work when @option{shift} is @code{auto}. 3870Note: The sync algorithm will work for those shift values for which 3871the guest clock runs ahead of the host clock. Typically this happens 3872when the shift value is high (how high depends on the host machine). 3873 3874When @option{rr} option is specified deterministic record/replay is enabled. 3875Replay log is written into @var{filename} file in record mode and 3876read from this file in replay mode. 3877 3878Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3879at the start of execution recording. In replay mode this option is used 3880to load the initial VM state. 3881ETEXI 3882 3883DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3884 "-watchdog model\n" \ 3885 " enable virtual hardware watchdog [default=none]\n", 3886 QEMU_ARCH_ALL) 3887STEXI 3888@item -watchdog @var{model} 3889@findex -watchdog 3890Create a virtual hardware watchdog device. Once enabled (by a guest 3891action), the watchdog must be periodically polled by an agent inside 3892the guest or else the guest will be restarted. Choose a model for 3893which your guest has drivers. 3894 3895The @var{model} is the model of hardware watchdog to emulate. Use 3896@code{-watchdog help} to list available hardware models. Only one 3897watchdog can be enabled for a guest. 3898 3899The following models may be available: 3900@table @option 3901@item ib700 3902iBASE 700 is a very simple ISA watchdog with a single timer. 3903@item i6300esb 3904Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3905dual-timer watchdog. 3906@item diag288 3907A virtual watchdog for s390x backed by the diagnose 288 hypercall 3908(currently KVM only). 3909@end table 3910ETEXI 3911 3912DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3913 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \ 3914 " action when watchdog fires [default=reset]\n", 3915 QEMU_ARCH_ALL) 3916STEXI 3917@item -watchdog-action @var{action} 3918@findex -watchdog-action 3919 3920The @var{action} controls what QEMU will do when the watchdog timer 3921expires. 3922The default is 3923@code{reset} (forcefully reset the guest). 3924Other possible actions are: 3925@code{shutdown} (attempt to gracefully shutdown the guest), 3926@code{poweroff} (forcefully poweroff the guest), 3927@code{inject-nmi} (inject a NMI into the guest), 3928@code{pause} (pause the guest), 3929@code{debug} (print a debug message and continue), or 3930@code{none} (do nothing). 3931 3932Note that the @code{shutdown} action requires that the guest responds 3933to ACPI signals, which it may not be able to do in the sort of 3934situations where the watchdog would have expired, and thus 3935@code{-watchdog-action shutdown} is not recommended for production use. 3936 3937Examples: 3938 3939@table @code 3940@item -watchdog i6300esb -watchdog-action pause 3941@itemx -watchdog ib700 3942@end table 3943ETEXI 3944 3945DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3946 "-echr chr set terminal escape character instead of ctrl-a\n", 3947 QEMU_ARCH_ALL) 3948STEXI 3949 3950@item -echr @var{numeric_ascii_value} 3951@findex -echr 3952Change the escape character used for switching to the monitor when using 3953monitor and serial sharing. The default is @code{0x01} when using the 3954@code{-nographic} option. @code{0x01} is equal to pressing 3955@code{Control-a}. You can select a different character from the ascii 3956control keys where 1 through 26 map to Control-a through Control-z. For 3957instance you could use the either of the following to change the escape 3958character to Control-t. 3959@table @code 3960@item -echr 0x14 3961@itemx -echr 20 3962@end table 3963ETEXI 3964 3965DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3966 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3967STEXI 3968@item -show-cursor 3969@findex -show-cursor 3970Show cursor. 3971ETEXI 3972 3973DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3974 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3975STEXI 3976@item -tb-size @var{n} 3977@findex -tb-size 3978Set TB size. 3979ETEXI 3980 3981DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3982 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3983 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3984 "-incoming unix:socketpath\n" \ 3985 " prepare for incoming migration, listen on\n" \ 3986 " specified protocol and socket address\n" \ 3987 "-incoming fd:fd\n" \ 3988 "-incoming exec:cmdline\n" \ 3989 " accept incoming migration on given file descriptor\n" \ 3990 " or from given external command\n" \ 3991 "-incoming defer\n" \ 3992 " wait for the URI to be specified via migrate_incoming\n", 3993 QEMU_ARCH_ALL) 3994STEXI 3995@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3996@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3997@findex -incoming 3998Prepare for incoming migration, listen on a given tcp port. 3999 4000@item -incoming unix:@var{socketpath} 4001Prepare for incoming migration, listen on a given unix socket. 4002 4003@item -incoming fd:@var{fd} 4004Accept incoming migration from a given filedescriptor. 4005 4006@item -incoming exec:@var{cmdline} 4007Accept incoming migration as an output from specified external command. 4008 4009@item -incoming defer 4010Wait for the URI to be specified via migrate_incoming. The monitor can 4011be used to change settings (such as migration parameters) prior to issuing 4012the migrate_incoming to allow the migration to begin. 4013ETEXI 4014 4015DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 4016 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 4017STEXI 4018@item -only-migratable 4019@findex -only-migratable 4020Only allow migratable devices. Devices will not be allowed to enter an 4021unmigratable state. 4022ETEXI 4023 4024DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 4025 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 4026STEXI 4027@item -nodefaults 4028@findex -nodefaults 4029Don't create default devices. Normally, QEMU sets the default devices like serial 4030port, parallel port, virtual console, monitor device, VGA adapter, floppy and 4031CD-ROM drive and others. The @code{-nodefaults} option will disable all those 4032default devices. 4033ETEXI 4034 4035#ifndef _WIN32 4036DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 4037 "-chroot dir chroot to dir just before starting the VM\n", 4038 QEMU_ARCH_ALL) 4039#endif 4040STEXI 4041@item -chroot @var{dir} 4042@findex -chroot 4043Immediately before starting guest execution, chroot to the specified 4044directory. Especially useful in combination with -runas. 4045ETEXI 4046 4047#ifndef _WIN32 4048DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 4049 "-runas user change to user id user just before starting the VM\n" \ 4050 " user can be numeric uid:gid instead\n", 4051 QEMU_ARCH_ALL) 4052#endif 4053STEXI 4054@item -runas @var{user} 4055@findex -runas 4056Immediately before starting guest execution, drop root privileges, switching 4057to the specified user. 4058ETEXI 4059 4060DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 4061 "-prom-env variable=value\n" 4062 " set OpenBIOS nvram variables\n", 4063 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 4064STEXI 4065@item -prom-env @var{variable}=@var{value} 4066@findex -prom-env 4067Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 4068ETEXI 4069DEF("semihosting", 0, QEMU_OPTION_semihosting, 4070 "-semihosting semihosting mode\n", 4071 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 4072 QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2) 4073STEXI 4074@item -semihosting 4075@findex -semihosting 4076Enable semihosting mode (ARM, M68K, Xtensa, MIPS, Nios II only). 4077ETEXI 4078DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 4079 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]]\n" \ 4080 " semihosting configuration\n", 4081QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 4082QEMU_ARCH_MIPS | QEMU_ARCH_NIOS2) 4083STEXI 4084@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,chardev=id][,arg=str[,...]] 4085@findex -semihosting-config 4086Enable and configure semihosting (ARM, M68K, Xtensa, MIPS, Nios II only). 4087@table @option 4088@item target=@code{native|gdb|auto} 4089Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 4090or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 4091during debug sessions and @code{native} otherwise. 4092@item chardev=@var{str1} 4093Send the output to a chardev backend output for native or auto output when not in gdb 4094@item arg=@var{str1},arg=@var{str2},... 4095Allows the user to pass input arguments, and can be used multiple times to build 4096up a list. The old-style @code{-kernel}/@code{-append} method of passing a 4097command line is still supported for backward compatibility. If both the 4098@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 4099specified, the former is passed to semihosting as it always takes precedence. 4100@end table 4101ETEXI 4102DEF("old-param", 0, QEMU_OPTION_old_param, 4103 "-old-param old param mode\n", QEMU_ARCH_ARM) 4104STEXI 4105@item -old-param 4106@findex -old-param (ARM) 4107Old param mode (ARM only). 4108ETEXI 4109 4110DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 4111 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \ 4112 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \ 4113 " Enable seccomp mode 2 system call filter (default 'off').\n" \ 4114 " use 'obsolete' to allow obsolete system calls that are provided\n" \ 4115 " by the kernel, but typically no longer used by modern\n" \ 4116 " C library implementations.\n" \ 4117 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \ 4118 " its privileges by blacklisting all set*uid|gid system calls.\n" \ 4119 " The value 'children' will deny set*uid|gid system calls for\n" \ 4120 " main QEMU process but will allow forks and execves to run unprivileged\n" \ 4121 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \ 4122 " blacklisting *fork and execve\n" \ 4123 " use 'resourcecontrol' to disable process affinity and schedular priority\n", 4124 QEMU_ARCH_ALL) 4125STEXI 4126@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}] 4127@findex -sandbox 4128Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 4129disable it. The default is 'off'. 4130@table @option 4131@item obsolete=@var{string} 4132Enable Obsolete system calls 4133@item elevateprivileges=@var{string} 4134Disable set*uid|gid system calls 4135@item spawn=@var{string} 4136Disable *fork and execve 4137@item resourcecontrol=@var{string} 4138Disable process affinity and schedular priority 4139@end table 4140ETEXI 4141 4142DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 4143 "-readconfig <file>\n", QEMU_ARCH_ALL) 4144STEXI 4145@item -readconfig @var{file} 4146@findex -readconfig 4147Read device configuration from @var{file}. This approach is useful when you want to spawn 4148QEMU process with many command line options but you don't want to exceed the command line 4149character limit. 4150ETEXI 4151DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 4152 "-writeconfig <file>\n" 4153 " read/write config file\n", QEMU_ARCH_ALL) 4154STEXI 4155@item -writeconfig @var{file} 4156@findex -writeconfig 4157Write device configuration to @var{file}. The @var{file} can be either filename to save 4158command line and device configuration into file or dash @code{-}) character to print the 4159output to stdout. This can be later used as input file for @code{-readconfig} option. 4160ETEXI 4161 4162DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 4163 "-no-user-config\n" 4164 " do not load default user-provided config files at startup\n", 4165 QEMU_ARCH_ALL) 4166STEXI 4167@item -no-user-config 4168@findex -no-user-config 4169The @code{-no-user-config} option makes QEMU not load any of the user-provided 4170config files on @var{sysconfdir}. 4171ETEXI 4172 4173DEF("trace", HAS_ARG, QEMU_OPTION_trace, 4174 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 4175 " specify tracing options\n", 4176 QEMU_ARCH_ALL) 4177STEXI 4178HXCOMM This line is not accurate, as some sub-options are backend-specific but 4179HXCOMM HX does not support conditional compilation of text. 4180@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 4181@findex -trace 4182@include qemu-option-trace.texi 4183ETEXI 4184 4185HXCOMM Internal use 4186DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 4187DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 4188 4189#ifdef __linux__ 4190DEF("enable-fips", 0, QEMU_OPTION_enablefips, 4191 "-enable-fips enable FIPS 140-2 compliance\n", 4192 QEMU_ARCH_ALL) 4193#endif 4194STEXI 4195@item -enable-fips 4196@findex -enable-fips 4197Enable FIPS 140-2 compliance mode. 4198ETEXI 4199 4200HXCOMM Deprecated by -accel tcg 4201DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 4202 4203DEF("msg", HAS_ARG, QEMU_OPTION_msg, 4204 "-msg timestamp[=on|off]\n" 4205 " change the format of messages\n" 4206 " on|off controls leading timestamps (default:on)\n", 4207 QEMU_ARCH_ALL) 4208STEXI 4209@item -msg timestamp[=on|off] 4210@findex -msg 4211prepend a timestamp to each log message.(default:on) 4212ETEXI 4213 4214DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 4215 "-dump-vmstate <file>\n" 4216 " Output vmstate information in JSON format to file.\n" 4217 " Use the scripts/vmstate-static-checker.py file to\n" 4218 " check for possible regressions in migration code\n" 4219 " by comparing two such vmstate dumps.\n", 4220 QEMU_ARCH_ALL) 4221STEXI 4222@item -dump-vmstate @var{file} 4223@findex -dump-vmstate 4224Dump json-encoded vmstate information for current machine type to file 4225in @var{file} 4226ETEXI 4227 4228DEF("enable-sync-profile", 0, QEMU_OPTION_enable_sync_profile, 4229 "-enable-sync-profile\n" 4230 " enable synchronization profiling\n", 4231 QEMU_ARCH_ALL) 4232STEXI 4233@item -enable-sync-profile 4234@findex -enable-sync-profile 4235Enable synchronization profiling. 4236ETEXI 4237 4238STEXI 4239@end table 4240ETEXI 4241DEFHEADING() 4242 4243DEFHEADING(Generic object creation:) 4244STEXI 4245@table @option 4246ETEXI 4247 4248DEF("object", HAS_ARG, QEMU_OPTION_object, 4249 "-object TYPENAME[,PROP1=VALUE1,...]\n" 4250 " create a new object of type TYPENAME setting properties\n" 4251 " in the order they are specified. Note that the 'id'\n" 4252 " property must be set. These objects are placed in the\n" 4253 " '/objects' path.\n", 4254 QEMU_ARCH_ALL) 4255STEXI 4256@item -object @var{typename}[,@var{prop1}=@var{value1},...] 4257@findex -object 4258Create a new object of type @var{typename} setting properties 4259in the order they are specified. Note that the 'id' 4260property must be set. These objects are placed in the 4261'/objects' path. 4262 4263@table @option 4264 4265@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off},discard-data=@var{on|off},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},align=@var{align} 4266 4267Creates a memory file backend object, which can be used to back 4268the guest RAM with huge pages. 4269 4270The @option{id} parameter is a unique ID that will be used to reference this 4271memory region when configuring the @option{-numa} argument. 4272 4273The @option{size} option provides the size of the memory region, and accepts 4274common suffixes, eg @option{500M}. 4275 4276The @option{mem-path} provides the path to either a shared memory or huge page 4277filesystem mount. 4278 4279The @option{share} boolean option determines whether the memory 4280region is marked as private to QEMU, or shared. The latter allows 4281a co-operating external process to access the QEMU memory region. 4282 4283The @option{share} is also required for pvrdma devices due to 4284limitations in the RDMA API provided by Linux. 4285 4286Setting share=on might affect the ability to configure NUMA 4287bindings for the memory backend under some circumstances, see 4288Documentation/vm/numa_memory_policy.txt on the Linux kernel 4289source tree for additional details. 4290 4291Setting the @option{discard-data} boolean option to @var{on} 4292indicates that file contents can be destroyed when QEMU exits, 4293to avoid unnecessarily flushing data to the backing file. Note 4294that @option{discard-data} is only an optimization, and QEMU 4295might not discard file contents if it aborts unexpectedly or is 4296terminated using SIGKILL. 4297 4298The @option{merge} boolean option enables memory merge, also known as 4299MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for 4300memory deduplication. 4301 4302Setting the @option{dump} boolean option to @var{off} excludes the memory from 4303core dumps. This feature is also known as MADV_DONTDUMP. 4304 4305The @option{prealloc} boolean option enables memory preallocation. 4306 4307The @option{host-nodes} option binds the memory range to a list of NUMA host 4308nodes. 4309 4310The @option{policy} option sets the NUMA policy to one of the following values: 4311 4312@table @option 4313@item @var{default} 4314default host policy 4315 4316@item @var{preferred} 4317prefer the given host node list for allocation 4318 4319@item @var{bind} 4320restrict memory allocation to the given host node list 4321 4322@item @var{interleave} 4323interleave memory allocations across the given host node list 4324@end table 4325 4326The @option{align} option specifies the base address alignment when 4327QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg 4328@option{2M}. Some backend store specified by @option{mem-path} 4329requires an alignment different than the default one used by QEMU, eg 4330the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In 4331such cases, users can specify the required alignment via this option. 4332 4333The @option{pmem} option specifies whether the backing file specified 4334by @option{mem-path} is in host persistent memory that can be accessed 4335using the SNIA NVM programming model (e.g. Intel NVDIMM). 4336If @option{pmem} is set to 'on', QEMU will take necessary operations to 4337guarantee the persistence of its own writes to @option{mem-path} 4338(e.g. in vNVDIMM label emulation and live migration). 4339Also, we will map the backend-file with MAP_SYNC flag, which ensures the 4340file metadata is in sync for @option{mem-path} in case of host crash 4341or a power failure. MAP_SYNC requires support from both the host kernel 4342(since Linux kernel 4.15) and the filesystem of @option{mem-path} mounted 4343with DAX option. 4344 4345@item -object memory-backend-ram,id=@var{id},merge=@var{on|off},dump=@var{on|off},share=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave} 4346 4347Creates a memory backend object, which can be used to back the guest RAM. 4348Memory backend objects offer more control than the @option{-m} option that is 4349traditionally used to define guest RAM. Please refer to 4350@option{memory-backend-file} for a description of the options. 4351 4352@item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},share=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size} 4353 4354Creates an anonymous memory file backend object, which allows QEMU to 4355share the memory with an external process (e.g. when using 4356vhost-user). The memory is allocated with memfd and optional 4357sealing. (Linux only) 4358 4359The @option{seal} option creates a sealed-file, that will block 4360further resizing the memory ('on' by default). 4361 4362The @option{hugetlb} option specify the file to be created resides in 4363the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with 4364the @option{hugetlb} option, the @option{hugetlbsize} option specify 4365the hugetlb page size on systems that support multiple hugetlb page 4366sizes (it must be a power of 2 value supported by the system). 4367 4368In some versions of Linux, the @option{hugetlb} option is incompatible 4369with the @option{seal} option (requires at least Linux 4.16). 4370 4371Please refer to @option{memory-backend-file} for a description of the 4372other options. 4373 4374The @option{share} boolean option is @var{on} by default with memfd. 4375 4376@item -object rng-builtin,id=@var{id} 4377 4378Creates a random number generator backend which obtains entropy from 4379QEMU builtin functions. The @option{id} parameter is a unique ID that 4380will be used to reference this entropy backend from the @option{virtio-rng} 4381device. By default, the @option{virtio-rng} device uses this RNG backend. 4382 4383@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4384 4385Creates a random number generator backend which obtains entropy from 4386a device on the host. The @option{id} parameter is a unique ID that 4387will be used to reference this entropy backend from the @option{virtio-rng} 4388device. The @option{filename} parameter specifies which file to obtain 4389entropy from and if omitted defaults to @option{/dev/urandom}. 4390 4391@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4392 4393Creates a random number generator backend which obtains entropy from 4394an external daemon running on the host. The @option{id} parameter is 4395a unique ID that will be used to reference this entropy backend from 4396the @option{virtio-rng} device. The @option{chardev} parameter is 4397the unique ID of a character device backend that provides the connection 4398to the RNG daemon. 4399 4400@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4401 4402Creates a TLS anonymous credentials object, which can be used to provide 4403TLS support on network backends. The @option{id} parameter is a unique 4404ID which network backends will use to access the credentials. The 4405@option{endpoint} is either @option{server} or @option{client} depending 4406on whether the QEMU network backend that uses the credentials will be 4407acting as a client or as a server. If @option{verify-peer} is enabled 4408(the default) then once the handshake is completed, the peer credentials 4409will be verified, though this is a no-op for anonymous credentials. 4410 4411The @var{dir} parameter tells QEMU where to find the credential 4412files. For server endpoints, this directory may contain a file 4413@var{dh-params.pem} providing diffie-hellman parameters to use 4414for the TLS server. If the file is missing, QEMU will generate 4415a set of DH parameters at startup. This is a computationally 4416expensive operation that consumes random pool entropy, so it is 4417recommended that a persistent set of parameters be generated 4418upfront and saved. 4419 4420@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] 4421 4422Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide 4423TLS support on network backends. The @option{id} parameter is a unique 4424ID which network backends will use to access the credentials. The 4425@option{endpoint} is either @option{server} or @option{client} depending 4426on whether the QEMU network backend that uses the credentials will be 4427acting as a client or as a server. For clients only, @option{username} 4428is the username which will be sent to the server. If omitted 4429it defaults to ``qemu''. 4430 4431The @var{dir} parameter tells QEMU where to find the keys file. 4432It is called ``@var{dir}/keys.psk'' and contains ``username:key'' 4433pairs. This file can most easily be created using the GnuTLS 4434@code{psktool} program. 4435 4436For server endpoints, @var{dir} may also contain a file 4437@var{dh-params.pem} providing diffie-hellman parameters to use 4438for the TLS server. If the file is missing, QEMU will generate 4439a set of DH parameters at startup. This is a computationally 4440expensive operation that consumes random pool entropy, so it is 4441recommended that a persistent set of parameters be generated 4442up front and saved. 4443 4444@item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},priority=@var{priority},verify-peer=@var{on|off},passwordid=@var{id} 4445 4446Creates a TLS anonymous credentials object, which can be used to provide 4447TLS support on network backends. The @option{id} parameter is a unique 4448ID which network backends will use to access the credentials. The 4449@option{endpoint} is either @option{server} or @option{client} depending 4450on whether the QEMU network backend that uses the credentials will be 4451acting as a client or as a server. If @option{verify-peer} is enabled 4452(the default) then once the handshake is completed, the peer credentials 4453will be verified. With x509 certificates, this implies that the clients 4454must be provided with valid client certificates too. 4455 4456The @var{dir} parameter tells QEMU where to find the credential 4457files. For server endpoints, this directory may contain a file 4458@var{dh-params.pem} providing diffie-hellman parameters to use 4459for the TLS server. If the file is missing, QEMU will generate 4460a set of DH parameters at startup. This is a computationally 4461expensive operation that consumes random pool entropy, so it is 4462recommended that a persistent set of parameters be generated 4463upfront and saved. 4464 4465For x509 certificate credentials the directory will contain further files 4466providing the x509 certificates. The certificates must be stored 4467in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4468@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4469@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4470 4471For the @var{server-key.pem} and @var{client-key.pem} files which 4472contain sensitive private keys, it is possible to use an encrypted 4473version by providing the @var{passwordid} parameter. This provides 4474the ID of a previously created @code{secret} object containing the 4475password for decryption. 4476 4477The @var{priority} parameter allows to override the global default 4478priority used by gnutls. This can be useful if the system administrator 4479needs to use a weaker set of crypto priorities for QEMU without 4480potentially forcing the weakness onto all applications. Or conversely 4481if one wants wants a stronger default for QEMU than for all other 4482applications, they can do this through this parameter. Its format is 4483a gnutls priority string as described at 4484@url{https://gnutls.org/manual/html_node/Priority-Strings.html}. 4485 4486@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4487 4488Interval @var{t} can't be 0, this filter batches the packet delivery: all 4489packets arriving in a given interval on netdev @var{netdevid} are delayed 4490until the end of the interval. Interval is in microseconds. 4491@option{status} is optional that indicate whether the netfilter is 4492on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4493 4494queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4495 4496@option{all}: the filter is attached both to the receive and the transmit 4497 queue of the netdev (default). 4498 4499@option{rx}: the filter is attached to the receive queue of the netdev, 4500 where it will receive packets sent to the netdev. 4501 4502@option{tx}: the filter is attached to the transmit queue of the netdev, 4503 where it will receive packets sent by the netdev. 4504 4505@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4506 4507filter-mirror on netdev @var{netdevid},mirror net packet to chardev@var{chardevid}, if it has the vnet_hdr_support flag, filter-mirror will mirror packet with vnet_hdr_len. 4508 4509@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4510 4511filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4512@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag, 4513filter-redirector will redirect packet with vnet_hdr_len. 4514Create a filter-redirector we need to differ outdev id from indev id, id can not 4515be the same. we can just use indev or outdev, but at least one of indev or outdev 4516need to be specified. 4517 4518@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support] 4519 4520Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4521secondary from primary to keep secondary tcp connection,and rewrite 4522tcp packet to primary from secondary make tcp packet can be handled by 4523client.if it has the vnet_hdr_support flag, we can parse packet with vnet header. 4524 4525usage: 4526colo secondary: 4527-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4528-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4529-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4530 4531@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4532 4533Dump the network traffic on netdev @var{dev} to the file specified by 4534@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4535The file format is libpcap, so it can be analyzed with tools such as tcpdump 4536or Wireshark. 4537 4538@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid},iothread=@var{id}[,vnet_hdr_support][,notify_dev=@var{id}] 4539 4540Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4541secondary packet. If the packets are same, we will output primary 4542packet to outdev@var{chardevid}, else we will notify colo-frame 4543do checkpoint and send primary packet to outdev@var{chardevid}. 4544In order to improve efficiency, we need to put the task of comparison 4545in another thread. If it has the vnet_hdr_support flag, colo compare 4546will send/recv packet with vnet_hdr_len. 4547If you want to use Xen COLO, will need the notify_dev to notify Xen 4548colo-frame to do checkpoint. 4549 4550we must use it with the help of filter-mirror and filter-redirector. 4551 4552@example 4553 4554KVM COLO 4555 4556primary: 4557-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4558-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4559-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4560-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4561-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4562-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4563-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4564-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4565-object iothread,id=iothread1 4566-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4567-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4568-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4569-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0,iothread=iothread1 4570 4571secondary: 4572-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4573-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4574-chardev socket,id=red0,host=3.3.3.3,port=9003 4575-chardev socket,id=red1,host=3.3.3.3,port=9004 4576-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4577-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4578 4579 4580Xen COLO 4581 4582primary: 4583-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4584-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4585-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4586-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4587-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4588-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4589-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4590-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4591-chardev socket,id=notify_way,host=3.3.3.3,port=9009,server,nowait 4592-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4593-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4594-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4595-object iothread,id=iothread1 4596-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0,notify_dev=nofity_way,iothread=iothread1 4597 4598secondary: 4599-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4600-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4601-chardev socket,id=red0,host=3.3.3.3,port=9003 4602-chardev socket,id=red1,host=3.3.3.3,port=9004 4603-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4604-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4605 4606@end example 4607 4608If you want to know the detail of above command line, you can read 4609the colo-compare git log. 4610 4611@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4612 4613Creates a cryptodev backend which executes crypto opreation from 4614the QEMU cipher APIS. The @var{id} parameter is 4615a unique ID that will be used to reference this cryptodev backend from 4616the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4617which specify the queue number of cryptodev backend, the default of 4618@var{queues} is 1. 4619 4620@example 4621 4622 # @value{qemu_system} \ 4623 [...] \ 4624 -object cryptodev-backend-builtin,id=cryptodev0 \ 4625 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4626 [...] 4627@end example 4628 4629@item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}] 4630 4631Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}. 4632The @var{id} parameter is a unique ID that will be used to reference this 4633cryptodev backend from the @option{virtio-crypto} device. 4634The chardev should be a unix domain socket backed one. The vhost-user uses 4635a specifically defined protocol to pass vhost ioctl replacement messages 4636to an application on the other end of the socket. 4637The @var{queues} parameter is optional, which specify the queue number 4638of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1. 4639 4640@example 4641 4642 # @value{qemu_system} \ 4643 [...] \ 4644 -chardev socket,id=chardev0,path=/path/to/socket \ 4645 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \ 4646 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4647 [...] 4648@end example 4649 4650@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4651@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4652 4653Defines a secret to store a password, encryption key, or some other sensitive 4654data. The sensitive data can either be passed directly via the @var{data} 4655parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4656parameter is insecure unless the sensitive data is encrypted. 4657 4658The sensitive data can be provided in raw format (the default), or base64. 4659When encoded as JSON, the raw format only supports valid UTF-8 characters, 4660so base64 is recommended for sending binary data. QEMU will convert from 4661which ever format is provided to the format it needs internally. eg, an 4662RBD password can be provided in raw format, even though it will be base64 4663encoded when passed onto the RBD sever. 4664 4665For added protection, it is possible to encrypt the data associated with 4666a secret using the AES-256-CBC cipher. Use of encryption is indicated 4667by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4668parameter provides the ID of a previously defined secret that contains 4669the AES-256 decryption key. This key should be 32-bytes long and be 4670base64 encoded. The @var{iv} parameter provides the random initialization 4671vector used for encryption of this particular secret and should be a 4672base64 encrypted string of the 16-byte IV. 4673 4674The simplest (insecure) usage is to provide the secret inline 4675 4676@example 4677 4678 # @value{qemu_system} -object secret,id=sec0,data=letmein,format=raw 4679 4680@end example 4681 4682The simplest secure usage is to provide the secret via a file 4683 4684 # printf "letmein" > mypasswd.txt 4685 # @value{qemu_system} -object secret,id=sec0,file=mypasswd.txt,format=raw 4686 4687For greater security, AES-256-CBC should be used. To illustrate usage, 4688consider the openssl command line tool which can encrypt the data. Note 4689that when encrypting, the plaintext must be padded to the cipher block 4690size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4691 4692First a master key needs to be created in base64 encoding: 4693 4694@example 4695 # openssl rand -base64 32 > key.b64 4696 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4697@end example 4698 4699Each secret to be encrypted needs to have a random initialization vector 4700generated. These do not need to be kept secret 4701 4702@example 4703 # openssl rand -base64 16 > iv.b64 4704 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4705@end example 4706 4707The secret to be defined can now be encrypted, in this case we're 4708telling openssl to base64 encode the result, but it could be left 4709as raw bytes if desired. 4710 4711@example 4712 # SECRET=$(printf "letmein" | 4713 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4714@end example 4715 4716When launching QEMU, create a master secret pointing to @code{key.b64} 4717and specify that to be used to decrypt the user password. Pass the 4718contents of @code{iv.b64} to the second secret 4719 4720@example 4721 # @value{qemu_system} \ 4722 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4723 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4724 data=$SECRET,iv=$(<iv.b64) 4725@end example 4726 4727@item -object sev-guest,id=@var{id},cbitpos=@var{cbitpos},reduced-phys-bits=@var{val},[sev-device=@var{string},policy=@var{policy},handle=@var{handle},dh-cert-file=@var{file},session-file=@var{file}] 4728 4729Create a Secure Encrypted Virtualization (SEV) guest object, which can be used 4730to provide the guest memory encryption support on AMD processors. 4731 4732When memory encryption is enabled, one of the physical address bit (aka the 4733C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos} 4734is used to provide the C-bit position. The C-bit position is Host family dependent 4735hence user must provide this value. On EPYC, the value should be 47. 4736 4737When memory encryption is enabled, we loose certain bits in physical address space. 4738The @option{reduced-phys-bits} is used to provide the number of bits we loose in 4739physical address space. Similar to C-bit, the value is Host family dependent. 4740On EPYC, the value should be 5. 4741 4742The @option{sev-device} provides the device file to use for communicating with 4743the SEV firmware running inside AMD Secure Processor. The default device is 4744'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are 4745created by CCP driver. 4746 4747The @option{policy} provides the guest policy to be enforced by the SEV firmware 4748and restrict what configuration and operational commands can be performed on this 4749guest by the hypervisor. The policy should be provided by the guest owner and is 4750bound to the guest and cannot be changed throughout the lifetime of the guest. 4751The default is 0. 4752 4753If guest @option{policy} allows sharing the key with another SEV guest then 4754@option{handle} can be use to provide handle of the guest from which to share 4755the key. 4756 4757The @option{dh-cert-file} and @option{session-file} provides the guest owner's 4758Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters 4759are used for establishing a cryptographic session with the guest owner to 4760negotiate keys used for attestation. The file must be encoded in base64. 4761 4762e.g to launch a SEV guest 4763@example 4764 # @value{qemu_system_x86} \ 4765 ...... 4766 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ 4767 -machine ...,memory-encryption=sev0 4768 ..... 4769 4770@end example 4771 4772 4773@item -object authz-simple,id=@var{id},identity=@var{string} 4774 4775Create an authorization object that will control access to network services. 4776 4777The @option{identity} parameter is identifies the user and its format 4778depends on the network service that authorization object is associated 4779with. For authorizing based on TLS x509 certificates, the identity must 4780be the x509 distinguished name. Note that care must be taken to escape 4781any commas in the distinguished name. 4782 4783An example authorization object to validate a x509 distinguished name 4784would look like: 4785@example 4786 # @value{qemu_system} \ 4787 ... 4788 -object 'authz-simple,id=auth0,identity=CN=laptop.example.com,,O=Example Org,,L=London,,ST=London,,C=GB' \ 4789 ... 4790@end example 4791 4792Note the use of quotes due to the x509 distinguished name containing 4793whitespace, and escaping of ','. 4794 4795@item -object authz-listfile,id=@var{id},filename=@var{path},refresh=@var{yes|no} 4796 4797Create an authorization object that will control access to network services. 4798 4799The @option{filename} parameter is the fully qualified path to a file 4800containing the access control list rules in JSON format. 4801 4802An example set of rules that match against SASL usernames might look 4803like: 4804 4805@example 4806 @{ 4807 "rules": [ 4808 @{ "match": "fred", "policy": "allow", "format": "exact" @}, 4809 @{ "match": "bob", "policy": "allow", "format": "exact" @}, 4810 @{ "match": "danb", "policy": "deny", "format": "glob" @}, 4811 @{ "match": "dan*", "policy": "allow", "format": "exact" @}, 4812 ], 4813 "policy": "deny" 4814 @} 4815@end example 4816 4817When checking access the object will iterate over all the rules and 4818the first rule to match will have its @option{policy} value returned 4819as the result. If no rules match, then the default @option{policy} 4820value is returned. 4821 4822The rules can either be an exact string match, or they can use the 4823simple UNIX glob pattern matching to allow wildcards to be used. 4824 4825If @option{refresh} is set to true the file will be monitored 4826and automatically reloaded whenever its content changes. 4827 4828As with the @code{authz-simple} object, the format of the identity 4829strings being matched depends on the network service, but is usually 4830a TLS x509 distinguished name, or a SASL username. 4831 4832An example authorization object to validate a SASL username 4833would look like: 4834@example 4835 # @value{qemu_system} \ 4836 ... 4837 -object authz-simple,id=auth0,filename=/etc/qemu/vnc-sasl.acl,refresh=yes 4838 ... 4839@end example 4840 4841@item -object authz-pam,id=@var{id},service=@var{string} 4842 4843Create an authorization object that will control access to network services. 4844 4845The @option{service} parameter provides the name of a PAM service to use 4846for authorization. It requires that a file @code{/etc/pam.d/@var{service}} 4847exist to provide the configuration for the @code{account} subsystem. 4848 4849An example authorization object to validate a TLS x509 distinguished 4850name would look like: 4851 4852@example 4853 # @value{qemu_system} \ 4854 ... 4855 -object authz-pam,id=auth0,service=qemu-vnc 4856 ... 4857@end example 4858 4859There would then be a corresponding config file for PAM at 4860@code{/etc/pam.d/qemu-vnc} that contains: 4861 4862@example 4863account requisite pam_listfile.so item=user sense=allow \ 4864 file=/etc/qemu/vnc.allow 4865@end example 4866 4867Finally the @code{/etc/qemu/vnc.allow} file would contain 4868the list of x509 distingished names that are permitted 4869access 4870 4871@example 4872CN=laptop.example.com,O=Example Home,L=London,ST=London,C=GB 4873@end example 4874 4875 4876@end table 4877 4878ETEXI 4879 4880 4881HXCOMM This is the last statement. Insert new options before this line! 4882STEXI 4883@end table 4884ETEXI 4885
