1HXCOMM Use DEFHEADING() to define headings in both help text and texi 2HXCOMM Text between STEXI and ETEXI are copied to texi version and 3HXCOMM discarded from C version 4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to 5HXCOMM construct option structures, enums and help message for specified 6HXCOMM architectures. 7HXCOMM HXCOMM can be used for comments, discarded from both texi and C 8 9DEFHEADING(Standard options:) 10STEXI 11@table @option 12ETEXI 13 14DEF("help", 0, QEMU_OPTION_h, 15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL) 16STEXI 17@item -h 18@findex -h 19Display help and exit 20ETEXI 21 22DEF("version", 0, QEMU_OPTION_version, 23 "-version display version information and exit\n", QEMU_ARCH_ALL) 24STEXI 25@item -version 26@findex -version 27Display version information and exit 28ETEXI 29 30DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ 31 "-machine [type=]name[,prop[=value][,...]]\n" 32 " selects emulated machine ('-machine help' for list)\n" 33 " property accel=accel1[:accel2[:...]] selects accelerator\n" 34 " supported accelerators are kvm, xen, hax, hvf, whpx or tcg (default: tcg)\n" 35 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n" 36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n" 37 " kvm_shadow_mem=size of KVM shadow MMU in bytes\n" 38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 39 " mem-merge=on|off controls memory merge support (default: on)\n" 40 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n" 41 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" 42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" 43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" 44 " nvdimm=on|off controls NVDIMM support (default=off)\n" 45 " enforce-config-section=on|off enforce configuration section migration (default=off)\n" 46 " s390-squash-mcss=on|off (deprecated) controls support for squashing into default css (default=off)\n" 47 " memory-encryption=@var{} memory encryption object to use (default=none)\n", 48 QEMU_ARCH_ALL) 49STEXI 50@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 51@findex -machine 52Select the emulated machine by @var{name}. Use @code{-machine help} to list 53available machines. 54 55For architectures which aim to support live migration compatibility 56across releases, each release will introduce a new versioned machine 57type. For example, the 2.8.0 release introduced machine types 58``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures. 59 60To allow live migration of guests from QEMU version 2.8.0, to QEMU 61version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8'' 62and ``pc-q35-2.8'' machines too. To allow users live migrating VMs 63to skip multiple intermediate releases when upgrading, new releases 64of QEMU will support machine types from many previous versions. 65 66Supported machine properties are: 67@table @option 68@item accel=@var{accels1}[:@var{accels2}[:...]] 69This is used to enable an accelerator. Depending on the target architecture, 70kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 71more than one accelerator specified, the next one is used if the previous one 72fails to initialize. 73@item kernel_irqchip=on|off 74Controls in-kernel irqchip support for the chosen accelerator when available. 75@item gfx_passthru=on|off 76Enables IGD GFX passthrough support for the chosen machine when available. 77@item vmport=on|off|auto 78Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 79value based on accel. For accel=xen the default is off otherwise the default 80is on. 81@item kvm_shadow_mem=size 82Defines the size of the KVM shadow MMU. 83@item dump-guest-core=on|off 84Include guest memory in a core dump. The default is on. 85@item mem-merge=on|off 86Enables or disables memory merge support. This feature, when supported by 87the host, de-duplicates identical memory pages among VMs instances 88(enabled by default). 89@item aes-key-wrap=on|off 90Enables or disables AES key wrapping support on s390-ccw hosts. This feature 91controls whether AES wrapping keys will be created to allow 92execution of AES cryptographic functions. The default is on. 93@item dea-key-wrap=on|off 94Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 95controls whether DEA wrapping keys will be created to allow 96execution of DEA cryptographic functions. The default is on. 97@item nvdimm=on|off 98Enables or disables NVDIMM support. The default is off. 99@item s390-squash-mcss=on|off 100Enables or disables squashing subchannels into the default css. 101The default is off. 102NOTE: This property is deprecated and will be removed in future releases. 103The ``s390-squash-mcss=on`` property has been obsoleted by allowing the 104cssid to be chosen freely. Instead of squashing subchannels into the 105default channel subsystem image for guests that do not support multiple 106channel subsystems, all devices can be put into the default channel 107subsystem image. 108@item enforce-config-section=on|off 109If @option{enforce-config-section} is set to @var{on}, force migration 110code to send configuration section even if the machine-type sets the 111@option{migration.send-configuration} property to @var{off}. 112NOTE: this parameter is deprecated. Please use @option{-global} 113@option{migration.send-configuration}=@var{on|off} instead. 114@item memory-encryption=@var{} 115Memory encryption object to use. The default is none. 116@end table 117ETEXI 118 119HXCOMM Deprecated by -machine 120DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 121 122DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 123 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 124STEXI 125@item -cpu @var{model} 126@findex -cpu 127Select CPU model (@code{-cpu help} for list and additional feature selection) 128ETEXI 129 130DEF("accel", HAS_ARG, QEMU_OPTION_accel, 131 "-accel [accel=]accelerator[,thread=single|multi]\n" 132 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n" 133 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL) 134STEXI 135@item -accel @var{name}[,prop=@var{value}[,...]] 136@findex -accel 137This is used to enable an accelerator. Depending on the target architecture, 138kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 139more than one accelerator specified, the next one is used if the previous one 140fails to initialize. 141@table @option 142@item thread=single|multi 143Controls number of TCG threads. When the TCG is multi-threaded there will be one 144thread per vCPU therefor taking advantage of additional host cores. The default 145is to enable multi-threading where both the back-end and front-ends support it and 146no incompatible TCG features have been enabled (e.g. icount/replay). 147@end table 148ETEXI 149 150DEF("smp", HAS_ARG, QEMU_OPTION_smp, 151 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 152 " set the number of CPUs to 'n' [default=1]\n" 153 " maxcpus= maximum number of total cpus, including\n" 154 " offline CPUs for hotplug, etc\n" 155 " cores= number of CPU cores on one socket\n" 156 " threads= number of threads on one CPU core\n" 157 " sockets= number of discrete sockets in the system\n", 158 QEMU_ARCH_ALL) 159STEXI 160@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 161@findex -smp 162Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 163CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 164to 4. 165For the PC target, the number of @var{cores} per socket, the number 166of @var{threads} per cores and the total number of @var{sockets} can be 167specified. Missing values will be computed. If any on the three values is 168given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 169specifies the maximum number of hotpluggable CPUs. 170ETEXI 171 172DEF("numa", HAS_ARG, QEMU_OPTION_numa, 173 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 174 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 175 "-numa dist,src=source,dst=destination,val=distance\n" 176 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n", 177 QEMU_ARCH_ALL) 178STEXI 179@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 180@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 181@itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance} 182@itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}] 183@findex -numa 184Define a NUMA node and assign RAM and VCPUs to it. 185Set the NUMA distance from a source node to a destination node. 186 187Legacy VCPU assignment uses @samp{cpus} option where 188@var{firstcpu} and @var{lastcpu} are CPU indexes. Each 189@samp{cpus} option represent a contiguous range of CPU indexes 190(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous 191set of VCPUs can be represented by providing multiple @samp{cpus} 192options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically 193split between them. 194 195For example, the following option assigns VCPUs 0, 1, 2 and 5 to 196a NUMA node: 197@example 198-numa node,cpus=0-2,cpus=5 199@end example 200 201@samp{cpu} option is a new alternative to @samp{cpus} option 202which uses @samp{socket-id|core-id|thread-id} properties to assign 203CPU objects to a @var{node} using topology layout properties of CPU. 204The set of properties is machine specific, and depends on used 205machine type/@samp{smp} options. It could be queried with 206@samp{hotpluggable-cpus} monitor command. 207@samp{node-id} property specifies @var{node} to which CPU object 208will be assigned, it's required for @var{node} to be declared 209with @samp{node} option before it's used with @samp{cpu} option. 210 211For example: 212@example 213-M pc \ 214-smp 1,sockets=2,maxcpus=2 \ 215-numa node,nodeid=0 -numa node,nodeid=1 \ 216-numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1 217@end example 218 219@samp{mem} assigns a given RAM amount to a node. @samp{memdev} 220assigns RAM from a given memory backend device to a node. If 221@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is 222split equally between them. 223 224@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, 225if one node uses @samp{memdev}, all of them have to use it. 226 227@var{source} and @var{destination} are NUMA node IDs. 228@var{distance} is the NUMA distance from @var{source} to @var{destination}. 229The distance from a node to itself is always 10. If any pair of nodes is 230given a distance, then all pairs must be given distances. Although, when 231distances are only given in one direction for each pair of nodes, then 232the distances in the opposite directions are assumed to be the same. If, 233however, an asymmetrical pair of distances is given for even one node 234pair, then all node pairs must be provided distance values for both 235directions, even when they are symmetrical. When a node is unreachable 236from another node, set the pair's distance to 255. 237 238Note that the -@option{numa} option doesn't allocate any of the 239specified resources, it just assigns existing resources to NUMA 240nodes. This means that one still has to use the @option{-m}, 241@option{-smp} options to allocate RAM and VCPUs respectively. 242 243ETEXI 244 245DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 246 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 247 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 248STEXI 249@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 250@findex -add-fd 251 252Add a file descriptor to an fd set. Valid options are: 253 254@table @option 255@item fd=@var{fd} 256This option defines the file descriptor of which a duplicate is added to fd set. 257The file descriptor cannot be stdin, stdout, or stderr. 258@item set=@var{set} 259This option defines the ID of the fd set to add the file descriptor to. 260@item opaque=@var{opaque} 261This option defines a free-form string that can be used to describe @var{fd}. 262@end table 263 264You can open an image using pre-opened file descriptors from an fd set: 265@example 266qemu-system-i386 267-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 268-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 269-drive file=/dev/fdset/2,index=0,media=disk 270@end example 271ETEXI 272 273DEF("set", HAS_ARG, QEMU_OPTION_set, 274 "-set group.id.arg=value\n" 275 " set <arg> parameter for item <id> of type <group>\n" 276 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 277STEXI 278@item -set @var{group}.@var{id}.@var{arg}=@var{value} 279@findex -set 280Set parameter @var{arg} for item @var{id} of type @var{group} 281ETEXI 282 283DEF("global", HAS_ARG, QEMU_OPTION_global, 284 "-global driver.property=value\n" 285 "-global driver=driver,property=property,value=value\n" 286 " set a global default for a driver property\n", 287 QEMU_ARCH_ALL) 288STEXI 289@item -global @var{driver}.@var{prop}=@var{value} 290@itemx -global driver=@var{driver},property=@var{property},value=@var{value} 291@findex -global 292Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 293 294@example 295qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img 296@end example 297 298In particular, you can use this to set driver properties for devices which are 299created automatically by the machine model. To create a device which is not 300created automatically and set properties on it, use -@option{device}. 301 302-global @var{driver}.@var{prop}=@var{value} is shorthand for -global 303driver=@var{driver},property=@var{prop},value=@var{value}. The 304longhand syntax works even when @var{driver} contains a dot. 305ETEXI 306 307DEF("boot", HAS_ARG, QEMU_OPTION_boot, 308 "-boot [order=drives][,once=drives][,menu=on|off]\n" 309 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 310 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 311 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 312 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 313 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 314 QEMU_ARCH_ALL) 315STEXI 316@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] 317@findex -boot 318Specify boot order @var{drives} as a string of drive letters. Valid 319drive letters depend on the target architecture. The x86 PC uses: a, b 320(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 321from network adapter 1-4), hard disk boot is the default. To apply a 322particular boot order only on the first startup, specify it via 323@option{once}. Note that the @option{order} or @option{once} parameter 324should not be used together with the @option{bootindex} property of 325devices, since the firmware implementations normally do not support both 326at the same time. 327 328Interactive boot menus/prompts can be enabled via @option{menu=on} as far 329as firmware/BIOS supports them. The default is non-interactive boot. 330 331A splash picture could be passed to bios, enabling user to show it as logo, 332when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 333supports them. Currently Seabios for X86 system support it. 334limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 335format(true color). The resolution should be supported by the SVGA mode, so 336the recommended is 320x240, 640x480, 800x640. 337 338A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 339when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 340reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 341system support it. 342 343Do strict boot via @option{strict=on} as far as firmware/BIOS 344supports it. This only effects when boot priority is changed by 345bootindex options. The default is non-strict boot. 346 347@example 348# try to boot from network first, then from hard disk 349qemu-system-i386 -boot order=nc 350# boot from CD-ROM first, switch back to default order after reboot 351qemu-system-i386 -boot once=d 352# boot with a splash picture for 5 seconds. 353qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 354@end example 355 356Note: The legacy format '-boot @var{drives}' is still supported but its 357use is discouraged as it may be removed from future versions. 358ETEXI 359 360DEF("m", HAS_ARG, QEMU_OPTION_m, 361 "-m [size=]megs[,slots=n,maxmem=size]\n" 362 " configure guest RAM\n" 363 " size: initial amount of guest memory\n" 364 " slots: number of hotplug slots (default: none)\n" 365 " maxmem: maximum amount of guest memory (default: none)\n" 366 "NOTE: Some architectures might enforce a specific granularity\n", 367 QEMU_ARCH_ALL) 368STEXI 369@item -m [size=]@var{megs}[,slots=n,maxmem=size] 370@findex -m 371Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 372Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 373megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 374could be used to set amount of hotpluggable memory slots and maximum amount of 375memory. Note that @var{maxmem} must be aligned to the page size. 376 377For example, the following command-line sets the guest startup RAM size to 3781GB, creates 3 slots to hotplug additional memory and sets the maximum 379memory the guest can reach to 4GB: 380 381@example 382qemu-system-x86_64 -m 1G,slots=3,maxmem=4G 383@end example 384 385If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 386be enabled and the guest startup RAM will never increase. 387ETEXI 388 389DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 390 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 391STEXI 392@item -mem-path @var{path} 393@findex -mem-path 394Allocate guest RAM from a temporarily created file in @var{path}. 395ETEXI 396 397DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 398 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 399 QEMU_ARCH_ALL) 400STEXI 401@item -mem-prealloc 402@findex -mem-prealloc 403Preallocate memory when using -mem-path. 404ETEXI 405 406DEF("k", HAS_ARG, QEMU_OPTION_k, 407 "-k language use keyboard layout (for example 'fr' for French)\n", 408 QEMU_ARCH_ALL) 409STEXI 410@item -k @var{language} 411@findex -k 412Use keyboard layout @var{language} (for example @code{fr} for 413French). This option is only needed where it is not easy to get raw PC 414keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses 415display). You don't normally need to use it on PC/Linux or PC/Windows 416hosts. 417 418The available layouts are: 419@example 420ar de-ch es fo fr-ca hu ja mk no pt-br sv 421da en-gb et fr fr-ch is lt nl pl ru th 422de en-us fi fr-be hr it lv nl-be pt sl tr 423@end example 424 425The default is @code{en-us}. 426ETEXI 427 428 429DEF("audio-help", 0, QEMU_OPTION_audio_help, 430 "-audio-help print list of audio drivers and their options\n", 431 QEMU_ARCH_ALL) 432STEXI 433@item -audio-help 434@findex -audio-help 435Will show the audio subsystem help: list of drivers, tunable 436parameters. 437ETEXI 438 439DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 440 "-soundhw c1,... enable audio support\n" 441 " and only specified sound cards (comma separated list)\n" 442 " use '-soundhw help' to get the list of supported cards\n" 443 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 444STEXI 445@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 446@findex -soundhw 447Enable audio and selected sound hardware. Use 'help' to print all 448available sound hardware. 449 450@example 451qemu-system-i386 -soundhw sb16,adlib disk.img 452qemu-system-i386 -soundhw es1370 disk.img 453qemu-system-i386 -soundhw ac97 disk.img 454qemu-system-i386 -soundhw hda disk.img 455qemu-system-i386 -soundhw all disk.img 456qemu-system-i386 -soundhw help 457@end example 458 459Note that Linux's i810_audio OSS kernel (for AC97) module might 460require manually specifying clocking. 461 462@example 463modprobe i810_audio clocking=48000 464@end example 465ETEXI 466 467DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 468 "-balloon virtio[,addr=str]\n" 469 " enable virtio balloon device (deprecated)\n", QEMU_ARCH_ALL) 470STEXI 471@item -balloon virtio[,addr=@var{addr}] 472@findex -balloon 473Enable virtio balloon device, optionally with PCI address @var{addr}. This 474option is deprecated, use @option{-device virtio-balloon} instead. 475ETEXI 476 477DEF("device", HAS_ARG, QEMU_OPTION_device, 478 "-device driver[,prop[=value][,...]]\n" 479 " add device (based on driver)\n" 480 " prop=value,... sets driver properties\n" 481 " use '-device help' to print all possible drivers\n" 482 " use '-device driver,help' to print all possible properties\n", 483 QEMU_ARCH_ALL) 484STEXI 485@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 486@findex -device 487Add device @var{driver}. @var{prop}=@var{value} sets driver 488properties. Valid properties depend on the driver. To get help on 489possible drivers and properties, use @code{-device help} and 490@code{-device @var{driver},help}. 491 492Some drivers are: 493@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}] 494 495Add an IPMI BMC. This is a simulation of a hardware management 496interface processor that normally sits on a system. It provides 497a watchdog and the ability to reset and power control the system. 498You need to connect this to an IPMI interface to make it useful 499 500The IPMI slave address to use for the BMC. The default is 0x20. 501This address is the BMC's address on the I2C network of management 502controllers. If you don't know what this means, it is safe to ignore 503it. 504 505@table @option 506@item bmc=@var{id} 507The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 508@item slave_addr=@var{val} 509Define slave address to use for the BMC. The default is 0x20. 510@item sdrfile=@var{file} 511file containing raw Sensor Data Records (SDR) data. The default is none. 512@item fruareasize=@var{val} 513size of a Field Replaceable Unit (FRU) area. The default is 1024. 514@item frudatafile=@var{file} 515file containing raw Field Replaceable Unit (FRU) inventory data. The default is none. 516@end table 517 518@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 519 520Add a connection to an external IPMI BMC simulator. Instead of 521locally emulating the BMC like the above item, instead connect 522to an external entity that provides the IPMI services. 523 524A connection is made to an external BMC simulator. If you do this, it 525is strongly recommended that you use the "reconnect=" chardev option 526to reconnect to the simulator if the connection is lost. Note that if 527this is not used carefully, it can be a security issue, as the 528interface has the ability to send resets, NMIs, and power off the VM. 529It's best if QEMU makes a connection to an external simulator running 530on a secure port on localhost, so neither the simulator nor QEMU is 531exposed to any outside network. 532 533See the "lanserv/README.vm" file in the OpenIPMI library for more 534details on the external interface. 535 536@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 537 538Add a KCS IPMI interafce on the ISA bus. This also adds a 539corresponding ACPI and SMBIOS entries, if appropriate. 540 541@table @option 542@item bmc=@var{id} 543The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 544@item ioport=@var{val} 545Define the I/O address of the interface. The default is 0xca0 for KCS. 546@item irq=@var{val} 547Define the interrupt to use. The default is 5. To disable interrupts, 548set this to 0. 549@end table 550 551@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 552 553Like the KCS interface, but defines a BT interface. The default port is 5540xe4 and the default interrupt is 5. 555 556ETEXI 557 558DEF("name", HAS_ARG, QEMU_OPTION_name, 559 "-name string1[,process=string2][,debug-threads=on|off]\n" 560 " set the name of the guest\n" 561 " string1 sets the window title and string2 the process name (on Linux)\n" 562 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 563 " NOTE: The thread names are for debugging and not a stable API.\n", 564 QEMU_ARCH_ALL) 565STEXI 566@item -name @var{name} 567@findex -name 568Sets the @var{name} of the guest. 569This name will be displayed in the SDL window caption. 570The @var{name} will also be used for the VNC server. 571Also optionally set the top visible process name in Linux. 572Naming of individual threads can also be enabled on Linux to aid debugging. 573ETEXI 574 575DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 576 "-uuid %08x-%04x-%04x-%04x-%012x\n" 577 " specify machine UUID\n", QEMU_ARCH_ALL) 578STEXI 579@item -uuid @var{uuid} 580@findex -uuid 581Set system UUID. 582ETEXI 583 584STEXI 585@end table 586ETEXI 587DEFHEADING() 588 589DEFHEADING(Block device options:) 590STEXI 591@table @option 592ETEXI 593 594DEF("fda", HAS_ARG, QEMU_OPTION_fda, 595 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 596DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 597STEXI 598@item -fda @var{file} 599@itemx -fdb @var{file} 600@findex -fda 601@findex -fdb 602Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 603ETEXI 604 605DEF("hda", HAS_ARG, QEMU_OPTION_hda, 606 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 607DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 608DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 609 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 610DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 611STEXI 612@item -hda @var{file} 613@itemx -hdb @var{file} 614@itemx -hdc @var{file} 615@itemx -hdd @var{file} 616@findex -hda 617@findex -hdb 618@findex -hdc 619@findex -hdd 620Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 621ETEXI 622 623DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 624 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 625 QEMU_ARCH_ALL) 626STEXI 627@item -cdrom @var{file} 628@findex -cdrom 629Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 630@option{-cdrom} at the same time). You can use the host CD-ROM by 631using @file{/dev/cdrom} as filename (@pxref{host_drives}). 632ETEXI 633 634DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev, 635 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n" 636 " [,cache.direct=on|off][,cache.no-flush=on|off]\n" 637 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n" 638 " [,driver specific parameters...]\n" 639 " configure a block backend\n", QEMU_ARCH_ALL) 640STEXI 641@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]] 642@findex -blockdev 643 644Define a new block driver node. Some of the options apply to all block drivers, 645other options are only accepted for a specific block driver. See below for a 646list of generic options and options for the most common block drivers. 647 648Options that expect a reference to another node (e.g. @code{file}) can be 649given in two ways. Either you specify the node name of an already existing node 650(file=@var{node-name}), or you define a new node inline, adding options 651for the referenced node after a dot (file.filename=@var{path},file.aio=native). 652 653A block driver node created with @option{-blockdev} can be used for a guest 654device by specifying its node name for the @code{drive} property in a 655@option{-device} argument that defines a block device. 656 657@table @option 658@item Valid options for any block driver node: 659 660@table @code 661@item driver 662Specifies the block driver to use for the given node. 663@item node-name 664This defines the name of the block driver node by which it will be referenced 665later. The name must be unique, i.e. it must not match the name of a different 666block driver node, or (if you use @option{-drive} as well) the ID of a drive. 667 668If no node name is specified, it is automatically generated. The generated node 669name is not intended to be predictable and changes between QEMU invocations. 670For the top level, an explicit node name must be specified. 671@item read-only 672Open the node read-only. Guest write attempts will fail. 673@item cache.direct 674The host page cache can be avoided with @option{cache.direct=on}. This will 675attempt to do disk IO directly to the guest's memory. QEMU may still perform an 676internal copy of the data. 677@item cache.no-flush 678In case you don't care about data integrity over host failures, you can use 679@option{cache.no-flush=on}. This option tells QEMU that it never needs to write 680any data to the disk but can instead keep things in cache. If anything goes 681wrong, like your host losing power, the disk storage getting disconnected 682accidentally, etc. your image will most probably be rendered unusable. 683@item discard=@var{discard} 684@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls 685whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are 686ignored or passed to the filesystem. Some machine types may not support 687discard requests. 688@item detect-zeroes=@var{detect-zeroes} 689@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 690conversion of plain zero writes by the OS to driver specific optimized 691zero write commands. You may even choose "unmap" if @var{discard} is set 692to "unmap" to allow a zero write to be converted to an @code{unmap} operation. 693@end table 694 695@item Driver-specific options for @code{file} 696 697This is the protocol-level block driver for accessing regular files. 698 699@table @code 700@item filename 701The path to the image file in the local filesystem 702@item aio 703Specifies the AIO backend (threads/native, default: threads) 704@item locking 705Specifies whether the image file is protected with Linux OFD / POSIX locks. The 706default is to use the Linux Open File Descriptor API if available, otherwise no 707lock is applied. (auto/on/off, default: auto) 708@end table 709Example: 710@example 711-blockdev driver=file,node-name=disk,filename=disk.img 712@end example 713 714@item Driver-specific options for @code{raw} 715 716This is the image format block driver for raw images. It is usually 717stacked on top of a protocol level block driver such as @code{file}. 718 719@table @code 720@item file 721Reference to or definition of the data source block driver node 722(e.g. a @code{file} driver node) 723@end table 724Example 1: 725@example 726-blockdev driver=file,node-name=disk_file,filename=disk.img 727-blockdev driver=raw,node-name=disk,file=disk_file 728@end example 729Example 2: 730@example 731-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img 732@end example 733 734@item Driver-specific options for @code{qcow2} 735 736This is the image format block driver for qcow2 images. It is usually 737stacked on top of a protocol level block driver such as @code{file}. 738 739@table @code 740@item file 741Reference to or definition of the data source block driver node 742(e.g. a @code{file} driver node) 743 744@item backing 745Reference to or definition of the backing file block device (default is taken 746from the image file). It is allowed to pass @code{null} here in order to disable 747the default backing file. 748 749@item lazy-refcounts 750Whether to enable the lazy refcounts feature (on/off; default is taken from the 751image file) 752 753@item cache-size 754The maximum total size of the L2 table and refcount block caches in bytes 755(default: 1048576 bytes or 8 clusters, whichever is larger) 756 757@item l2-cache-size 758The maximum size of the L2 table cache in bytes 759(default: 4/5 of the total cache size) 760 761@item refcount-cache-size 762The maximum size of the refcount block cache in bytes 763(default: 1/5 of the total cache size) 764 765@item cache-clean-interval 766Clean unused entries in the L2 and refcount caches. The interval is in seconds. 767The default value is 0 and it disables this feature. 768 769@item pass-discard-request 770Whether discard requests to the qcow2 device should be forwarded to the data 771source (on/off; default: on if discard=unmap is specified, off otherwise) 772 773@item pass-discard-snapshot 774Whether discard requests for the data source should be issued when a snapshot 775operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off; 776default: on) 777 778@item pass-discard-other 779Whether discard requests for the data source should be issued on other 780occasions where a cluster gets freed (on/off; default: off) 781 782@item overlap-check 783Which overlap checks to perform for writes to the image 784(none/constant/cached/all; default: cached). For details or finer 785granularity control refer to the QAPI documentation of @code{blockdev-add}. 786@end table 787 788Example 1: 789@example 790-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2 791-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216 792@end example 793Example 2: 794@example 795-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2 796@end example 797 798@item Driver-specific options for other drivers 799Please refer to the QAPI documentation of the @code{blockdev-add} QMP command. 800 801@end table 802 803ETEXI 804 805DEF("drive", HAS_ARG, QEMU_OPTION_drive, 806 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 807 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 808 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 809 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 810 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 811 " [,readonly=on|off][,copy-on-read=on|off]\n" 812 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 813 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 814 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 815 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 816 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 817 " [[,iops_size=is]]\n" 818 " [[,group=g]]\n" 819 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 820STEXI 821@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 822@findex -drive 823 824Define a new drive. This includes creating a block driver node (the backend) as 825well as a guest device, and is mostly a shortcut for defining the corresponding 826@option{-blockdev} and @option{-device} options. 827 828@option{-drive} accepts all options that are accepted by @option{-blockdev}. In 829addition, it knows the following options: 830 831@table @option 832@item file=@var{file} 833This option defines which disk image (@pxref{disk_images}) to use with 834this drive. If the filename contains comma, you must double it 835(for instance, "file=my,,file" to use file "my,file"). 836 837Special files such as iSCSI devices can be specified using protocol 838specific URLs. See the section for "Device URL Syntax" for more information. 839@item if=@var{interface} 840This option defines on which type on interface the drive is connected. 841Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none. 842@item bus=@var{bus},unit=@var{unit} 843These options define where is connected the drive by defining the bus number and 844the unit id. 845@item index=@var{index} 846This option defines where is connected the drive by using an index in the list 847of available connectors of a given interface type. 848@item media=@var{media} 849This option defines the type of the media: disk or cdrom. 850@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 851Force disk physical geometry and the optional BIOS translation (trans=none or 852lba). These parameters are deprecated, use the corresponding parameters 853of @code{-device} instead. 854@item snapshot=@var{snapshot} 855@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 856(see @option{-snapshot}). 857@item cache=@var{cache} 858@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" 859and controls how the host cache is used to access block data. This is a 860shortcut that sets the @option{cache.direct} and @option{cache.no-flush} 861options (as in @option{-blockdev}), and additionally @option{cache.writeback}, 862which provides a default for the @option{write-cache} option of block guest 863devices (as in @option{-device}). The modes correspond to the following 864settings: 865 866@c Our texi2pod.pl script doesn't support @multitable, so fall back to using 867@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage 868@c and the HTML output. 869@example 870@ │ cache.writeback cache.direct cache.no-flush 871─────────────┼───────────────────────────────────────────────── 872writeback │ on off off 873none │ on on off 874writethrough │ off off off 875directsync │ off on off 876unsafe │ on off on 877@end example 878 879The default mode is @option{cache=writeback}. 880 881@item aio=@var{aio} 882@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 883@item format=@var{format} 884Specify which disk @var{format} will be used rather than detecting 885the format. Can be used to specify format=raw to avoid interpreting 886an untrusted format header. 887@item serial=@var{serial} 888This option specifies the serial number to assign to the device. This 889parameter is deprecated, use the corresponding parameter of @code{-device} 890instead. 891@item addr=@var{addr} 892Specify the controller's PCI address (if=virtio only). This parameter is 893deprecated, use the corresponding parameter of @code{-device} instead. 894@item werror=@var{action},rerror=@var{action} 895Specify which @var{action} to take on write and read errors. Valid actions are: 896"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 897"report" (report the error to the guest), "enospc" (pause QEMU only if the 898host disk is full; report the error to the guest otherwise). 899The default setting is @option{werror=enospc} and @option{rerror=report}. 900@item copy-on-read=@var{copy-on-read} 901@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 902file sectors into the image file. 903@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w} 904Specify bandwidth throttling limits in bytes per second, either for all request 905types or for reads or writes only. Small values can lead to timeouts or hangs 906inside the guest. A safe minimum for disks is 2 MB/s. 907@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm} 908Specify bursts in bytes per second, either for all request types or for reads 909or writes only. Bursts allow the guest I/O to spike above the limit 910temporarily. 911@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w} 912Specify request rate limits in requests per second, either for all request 913types or for reads or writes only. 914@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm} 915Specify bursts in requests per second, either for all request types or for reads 916or writes only. Bursts allow the guest I/O to spike above the limit 917temporarily. 918@item iops_size=@var{is} 919Let every @var{is} bytes of a request count as a new request for iops 920throttling purposes. Use this option to prevent guests from circumventing iops 921limits by sending fewer but larger requests. 922@item group=@var{g} 923Join a throttling quota group with given name @var{g}. All drives that are 924members of the same group are accounted for together. Use this option to 925prevent guests from circumventing throttling limits by using many small disks 926instead of a single larger disk. 927@end table 928 929By default, the @option{cache.writeback=on} mode is used. It will report data 930writes as completed as soon as the data is present in the host page cache. 931This is safe as long as your guest OS makes sure to correctly flush disk caches 932where needed. If your guest OS does not handle volatile disk write caches 933correctly and your host crashes or loses power, then the guest may experience 934data corruption. 935 936For such guests, you should consider using @option{cache.writeback=off}. This 937means that the host page cache will be used to read and write data, but write 938notification will be sent to the guest only after QEMU has made sure to flush 939each write to the disk. Be aware that this has a major impact on performance. 940 941When using the @option{-snapshot} option, unsafe caching is always used. 942 943Copy-on-read avoids accessing the same backing file sectors repeatedly and is 944useful when the backing file is over a slow network. By default copy-on-read 945is off. 946 947Instead of @option{-cdrom} you can use: 948@example 949qemu-system-i386 -drive file=file,index=2,media=cdrom 950@end example 951 952Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 953use: 954@example 955qemu-system-i386 -drive file=file,index=0,media=disk 956qemu-system-i386 -drive file=file,index=1,media=disk 957qemu-system-i386 -drive file=file,index=2,media=disk 958qemu-system-i386 -drive file=file,index=3,media=disk 959@end example 960 961You can open an image using pre-opened file descriptors from an fd set: 962@example 963qemu-system-i386 964-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 965-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 966-drive file=/dev/fdset/2,index=0,media=disk 967@end example 968 969You can connect a CDROM to the slave of ide0: 970@example 971qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 972@end example 973 974If you don't specify the "file=" argument, you define an empty drive: 975@example 976qemu-system-i386 -drive if=ide,index=1,media=cdrom 977@end example 978 979Instead of @option{-fda}, @option{-fdb}, you can use: 980@example 981qemu-system-i386 -drive file=file,index=0,if=floppy 982qemu-system-i386 -drive file=file,index=1,if=floppy 983@end example 984 985By default, @var{interface} is "ide" and @var{index} is automatically 986incremented: 987@example 988qemu-system-i386 -drive file=a -drive file=b" 989@end example 990is interpreted like: 991@example 992qemu-system-i386 -hda a -hdb b 993@end example 994ETEXI 995 996DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 997 "-mtdblock file use 'file' as on-board Flash memory image\n", 998 QEMU_ARCH_ALL) 999STEXI 1000@item -mtdblock @var{file} 1001@findex -mtdblock 1002Use @var{file} as on-board Flash memory image. 1003ETEXI 1004 1005DEF("sd", HAS_ARG, QEMU_OPTION_sd, 1006 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 1007STEXI 1008@item -sd @var{file} 1009@findex -sd 1010Use @var{file} as SecureDigital card image. 1011ETEXI 1012 1013DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 1014 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 1015STEXI 1016@item -pflash @var{file} 1017@findex -pflash 1018Use @var{file} as a parallel flash image. 1019ETEXI 1020 1021DEF("snapshot", 0, QEMU_OPTION_snapshot, 1022 "-snapshot write to temporary files instead of disk image files\n", 1023 QEMU_ARCH_ALL) 1024STEXI 1025@item -snapshot 1026@findex -snapshot 1027Write to temporary files instead of disk image files. In this case, 1028the raw disk image you use is not written back. You can however force 1029the write back by pressing @key{C-a s} (@pxref{disk_images}). 1030ETEXI 1031 1032DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 1033 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 1034 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n" 1035 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n" 1036 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n" 1037 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n" 1038 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n" 1039 " [[,throttling.iops-size=is]]\n", 1040 QEMU_ARCH_ALL) 1041 1042STEXI 1043 1044@item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}] 1045@findex -fsdev 1046Define a new file system device. Valid options are: 1047@table @option 1048@item @var{fsdriver} 1049This option specifies the fs driver backend to use. 1050Currently "local", "handle" and "proxy" file system drivers are supported. 1051@item id=@var{id} 1052Specifies identifier for this device 1053@item path=@var{path} 1054Specifies the export path for the file system device. Files under 1055this path will be available to the 9p client on the guest. 1056@item security_model=@var{security_model} 1057Specifies the security model to be used for this export path. 1058Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1059In "passthrough" security model, files are stored using the same 1060credentials as they are created on the guest. This requires QEMU 1061to run as root. In "mapped-xattr" security model, some of the file 1062attributes like uid, gid, mode bits and link target are stored as 1063file attributes. For "mapped-file" these attributes are stored in the 1064hidden .virtfs_metadata directory. Directories exported by this security model cannot 1065interact with other unix tools. "none" security model is same as 1066passthrough except the sever won't report failures if it fails to 1067set file attributes like ownership. Security model is mandatory 1068only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 1069security model as a parameter. 1070@item writeout=@var{writeout} 1071This is an optional argument. The only supported value is "immediate". 1072This means that host page cache will be used to read and write data but 1073write notification will be sent to the guest only when the data has been 1074reported as written by the storage subsystem. 1075@item readonly 1076Enables exporting 9p share as a readonly mount for guests. By default 1077read-write access is given. 1078@item socket=@var{socket} 1079Enables proxy filesystem driver to use passed socket file for communicating 1080with virtfs-proxy-helper 1081@item sock_fd=@var{sock_fd} 1082Enables proxy filesystem driver to use passed socket descriptor for 1083communicating with virtfs-proxy-helper. Usually a helper like libvirt 1084will create socketpair and pass one of the fds as sock_fd 1085@item fmode=@var{fmode} 1086Specifies the default mode for newly created files on the host. Works only 1087with security models "mapped-xattr" and "mapped-file". 1088@item dmode=@var{dmode} 1089Specifies the default mode for newly created directories on the host. Works 1090only with security models "mapped-xattr" and "mapped-file". 1091@end table 1092 1093-fsdev option is used along with -device driver "virtio-9p-pci". 1094@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 1095Options for virtio-9p-pci driver are: 1096@table @option 1097@item fsdev=@var{id} 1098Specifies the id value specified along with -fsdev option 1099@item mount_tag=@var{mount_tag} 1100Specifies the tag name to be used by the guest to mount this export point 1101@end table 1102 1103ETEXI 1104 1105DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 1106 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 1107 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n", 1108 QEMU_ARCH_ALL) 1109 1110STEXI 1111 1112@item -virtfs @var{fsdriver}[,path=@var{path}],mount_tag=@var{mount_tag}[,security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}] 1113@findex -virtfs 1114 1115The general form of a Virtual File system pass-through options are: 1116@table @option 1117@item @var{fsdriver} 1118This option specifies the fs driver backend to use. 1119Currently "local", "handle" and "proxy" file system drivers are supported. 1120@item id=@var{id} 1121Specifies identifier for this device 1122@item path=@var{path} 1123Specifies the export path for the file system device. Files under 1124this path will be available to the 9p client on the guest. 1125@item security_model=@var{security_model} 1126Specifies the security model to be used for this export path. 1127Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1128In "passthrough" security model, files are stored using the same 1129credentials as they are created on the guest. This requires QEMU 1130to run as root. In "mapped-xattr" security model, some of the file 1131attributes like uid, gid, mode bits and link target are stored as 1132file attributes. For "mapped-file" these attributes are stored in the 1133hidden .virtfs_metadata directory. Directories exported by this security model cannot 1134interact with other unix tools. "none" security model is same as 1135passthrough except the sever won't report failures if it fails to 1136set file attributes like ownership. Security model is mandatory only 1137for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 1138model as a parameter. 1139@item writeout=@var{writeout} 1140This is an optional argument. The only supported value is "immediate". 1141This means that host page cache will be used to read and write data but 1142write notification will be sent to the guest only when the data has been 1143reported as written by the storage subsystem. 1144@item readonly 1145Enables exporting 9p share as a readonly mount for guests. By default 1146read-write access is given. 1147@item socket=@var{socket} 1148Enables proxy filesystem driver to use passed socket file for 1149communicating with virtfs-proxy-helper. Usually a helper like libvirt 1150will create socketpair and pass one of the fds as sock_fd 1151@item sock_fd 1152Enables proxy filesystem driver to use passed 'sock_fd' as the socket 1153descriptor for interfacing with virtfs-proxy-helper 1154@item fmode=@var{fmode} 1155Specifies the default mode for newly created files on the host. Works only 1156with security models "mapped-xattr" and "mapped-file". 1157@item dmode=@var{dmode} 1158Specifies the default mode for newly created directories on the host. Works 1159only with security models "mapped-xattr" and "mapped-file". 1160@end table 1161ETEXI 1162 1163DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 1164 "-virtfs_synth Create synthetic file system image\n", 1165 QEMU_ARCH_ALL) 1166STEXI 1167@item -virtfs_synth 1168@findex -virtfs_synth 1169Create synthetic file system image 1170ETEXI 1171 1172DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 1173 "-iscsi [user=user][,password=password]\n" 1174 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 1175 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 1176 " [,timeout=timeout]\n" 1177 " iSCSI session parameters\n", QEMU_ARCH_ALL) 1178 1179STEXI 1180@item -iscsi 1181@findex -iscsi 1182Configure iSCSI session parameters. 1183ETEXI 1184 1185STEXI 1186@end table 1187ETEXI 1188DEFHEADING() 1189 1190DEFHEADING(USB options:) 1191STEXI 1192@table @option 1193ETEXI 1194 1195DEF("usb", 0, QEMU_OPTION_usb, 1196 "-usb enable the USB driver (if it is not used by default yet)\n", 1197 QEMU_ARCH_ALL) 1198STEXI 1199@item -usb 1200@findex -usb 1201Enable the USB driver (if it is not used by default yet). 1202ETEXI 1203 1204DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 1205 "-usbdevice name add the host or guest USB device 'name'\n", 1206 QEMU_ARCH_ALL) 1207STEXI 1208 1209@item -usbdevice @var{devname} 1210@findex -usbdevice 1211Add the USB device @var{devname}. Note that this option is deprecated, 1212please use @code{-device usb-...} instead. @xref{usb_devices}. 1213 1214@table @option 1215 1216@item mouse 1217Virtual Mouse. This will override the PS/2 mouse emulation when activated. 1218 1219@item tablet 1220Pointer device that uses absolute coordinates (like a touchscreen). This 1221means QEMU is able to report the mouse position without having to grab the 1222mouse. Also overrides the PS/2 mouse emulation when activated. 1223 1224@item braille 1225Braille device. This will use BrlAPI to display the braille output on a real 1226or fake device. 1227 1228@end table 1229ETEXI 1230 1231STEXI 1232@end table 1233ETEXI 1234DEFHEADING() 1235 1236DEFHEADING(Display options:) 1237STEXI 1238@table @option 1239ETEXI 1240 1241DEF("display", HAS_ARG, QEMU_OPTION_display, 1242 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 1243 " [,window_close=on|off][,gl=on|core|es|off]\n" 1244 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 1245 "-display vnc=<display>[,<optargs>]\n" 1246 "-display curses\n" 1247 "-display none" 1248 " select display type\n" 1249 "The default display is equivalent to\n" 1250#if defined(CONFIG_GTK) 1251 "\t\"-display gtk\"\n" 1252#elif defined(CONFIG_SDL) 1253 "\t\"-display sdl\"\n" 1254#elif defined(CONFIG_COCOA) 1255 "\t\"-display cocoa\"\n" 1256#elif defined(CONFIG_VNC) 1257 "\t\"-vnc localhost:0,to=99,id=default\"\n" 1258#else 1259 "\t\"-display none\"\n" 1260#endif 1261 , QEMU_ARCH_ALL) 1262STEXI 1263@item -display @var{type} 1264@findex -display 1265Select type of display to use. This option is a replacement for the 1266old style -sdl/-curses/... options. Valid values for @var{type} are 1267@table @option 1268@item sdl 1269Display video output via SDL (usually in a separate graphics 1270window; see the SDL documentation for other possibilities). 1271@item curses 1272Display video output via curses. For graphics device models which 1273support a text mode, QEMU can display this output using a 1274curses/ncurses interface. Nothing is displayed when the graphics 1275device is in graphical mode or if the graphics device does not support 1276a text mode. Generally only the VGA device models support text mode. 1277@item none 1278Do not display video output. The guest will still see an emulated 1279graphics card, but its output will not be displayed to the QEMU 1280user. This option differs from the -nographic option in that it 1281only affects what is done with video output; -nographic also changes 1282the destination of the serial and parallel port data. 1283@item gtk 1284Display video output in a GTK window. This interface provides drop-down 1285menus and other UI elements to configure and control the VM during 1286runtime. 1287@item vnc 1288Start a VNC server on display <arg> 1289@end table 1290ETEXI 1291 1292DEF("nographic", 0, QEMU_OPTION_nographic, 1293 "-nographic disable graphical output and redirect serial I/Os to console\n", 1294 QEMU_ARCH_ALL) 1295STEXI 1296@item -nographic 1297@findex -nographic 1298Normally, if QEMU is compiled with graphical window support, it displays 1299output such as guest graphics, guest console, and the QEMU monitor in a 1300window. With this option, you can totally disable graphical output so 1301that QEMU is a simple command line application. The emulated serial port 1302is redirected on the console and muxed with the monitor (unless 1303redirected elsewhere explicitly). Therefore, you can still use QEMU to 1304debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1305switching between the console and monitor. 1306ETEXI 1307 1308DEF("curses", 0, QEMU_OPTION_curses, 1309 "-curses shorthand for -display curses\n", 1310 QEMU_ARCH_ALL) 1311STEXI 1312@item -curses 1313@findex -curses 1314Normally, if QEMU is compiled with graphical window support, it displays 1315output such as guest graphics, guest console, and the QEMU monitor in a 1316window. With this option, QEMU can display the VGA output when in text 1317mode using a curses/ncurses interface. Nothing is displayed in graphical 1318mode. 1319ETEXI 1320 1321DEF("no-frame", 0, QEMU_OPTION_no_frame, 1322 "-no-frame open SDL window without a frame and window decorations\n", 1323 QEMU_ARCH_ALL) 1324STEXI 1325@item -no-frame 1326@findex -no-frame 1327Do not use decorations for SDL windows and start them using the whole 1328available screen space. This makes the using QEMU in a dedicated desktop 1329workspace more convenient. 1330ETEXI 1331 1332DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1333 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1334 QEMU_ARCH_ALL) 1335STEXI 1336@item -alt-grab 1337@findex -alt-grab 1338Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1339affects the special keys (for fullscreen, monitor-mode switching, etc). 1340ETEXI 1341 1342DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1343 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1344 QEMU_ARCH_ALL) 1345STEXI 1346@item -ctrl-grab 1347@findex -ctrl-grab 1348Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1349affects the special keys (for fullscreen, monitor-mode switching, etc). 1350ETEXI 1351 1352DEF("no-quit", 0, QEMU_OPTION_no_quit, 1353 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1354STEXI 1355@item -no-quit 1356@findex -no-quit 1357Disable SDL window close capability. 1358ETEXI 1359 1360DEF("sdl", 0, QEMU_OPTION_sdl, 1361 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1362STEXI 1363@item -sdl 1364@findex -sdl 1365Enable SDL. 1366ETEXI 1367 1368DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1369 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1370 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1371 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1372 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1373 " [,tls-ciphers=<list>]\n" 1374 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1375 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1376 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1377 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1378 " [,jpeg-wan-compression=[auto|never|always]]\n" 1379 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1380 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1381 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1382 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1383 " [,gl=[on|off]][,rendernode=<file>]\n" 1384 " enable spice\n" 1385 " at least one of {port, tls-port} is mandatory\n", 1386 QEMU_ARCH_ALL) 1387STEXI 1388@item -spice @var{option}[,@var{option}[,...]] 1389@findex -spice 1390Enable the spice remote desktop protocol. Valid options are 1391 1392@table @option 1393 1394@item port=<nr> 1395Set the TCP port spice is listening on for plaintext channels. 1396 1397@item addr=<addr> 1398Set the IP address spice is listening on. Default is any address. 1399 1400@item ipv4 1401@itemx ipv6 1402@itemx unix 1403Force using the specified IP version. 1404 1405@item password=<secret> 1406Set the password you need to authenticate. 1407 1408@item sasl 1409Require that the client use SASL to authenticate with the spice. 1410The exact choice of authentication method used is controlled from the 1411system / user's SASL configuration file for the 'qemu' service. This 1412is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1413unprivileged user, an environment variable SASL_CONF_PATH can be used 1414to make it search alternate locations for the service config. 1415While some SASL auth methods can also provide data encryption (eg GSSAPI), 1416it is recommended that SASL always be combined with the 'tls' and 1417'x509' settings to enable use of SSL and server certificates. This 1418ensures a data encryption preventing compromise of authentication 1419credentials. 1420 1421@item disable-ticketing 1422Allow client connects without authentication. 1423 1424@item disable-copy-paste 1425Disable copy paste between the client and the guest. 1426 1427@item disable-agent-file-xfer 1428Disable spice-vdagent based file-xfer between the client and the guest. 1429 1430@item tls-port=<nr> 1431Set the TCP port spice is listening on for encrypted channels. 1432 1433@item x509-dir=<dir> 1434Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1435 1436@item x509-key-file=<file> 1437@itemx x509-key-password=<file> 1438@itemx x509-cert-file=<file> 1439@itemx x509-cacert-file=<file> 1440@itemx x509-dh-key-file=<file> 1441The x509 file names can also be configured individually. 1442 1443@item tls-ciphers=<list> 1444Specify which ciphers to use. 1445 1446@item tls-channel=[main|display|cursor|inputs|record|playback] 1447@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1448Force specific channel to be used with or without TLS encryption. The 1449options can be specified multiple times to configure multiple 1450channels. The special name "default" can be used to set the default 1451mode. For channels which are not explicitly forced into one mode the 1452spice client is allowed to pick tls/plaintext as he pleases. 1453 1454@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1455Configure image compression (lossless). 1456Default is auto_glz. 1457 1458@item jpeg-wan-compression=[auto|never|always] 1459@itemx zlib-glz-wan-compression=[auto|never|always] 1460Configure wan image compression (lossy for slow links). 1461Default is auto. 1462 1463@item streaming-video=[off|all|filter] 1464Configure video stream detection. Default is off. 1465 1466@item agent-mouse=[on|off] 1467Enable/disable passing mouse events via vdagent. Default is on. 1468 1469@item playback-compression=[on|off] 1470Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1471 1472@item seamless-migration=[on|off] 1473Enable/disable spice seamless migration. Default is off. 1474 1475@item gl=[on|off] 1476Enable/disable OpenGL context. Default is off. 1477 1478@item rendernode=<file> 1479DRM render node for OpenGL rendering. If not specified, it will pick 1480the first available. (Since 2.9) 1481 1482@end table 1483ETEXI 1484 1485DEF("portrait", 0, QEMU_OPTION_portrait, 1486 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1487 QEMU_ARCH_ALL) 1488STEXI 1489@item -portrait 1490@findex -portrait 1491Rotate graphical output 90 deg left (only PXA LCD). 1492ETEXI 1493 1494DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1495 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1496 QEMU_ARCH_ALL) 1497STEXI 1498@item -rotate @var{deg} 1499@findex -rotate 1500Rotate graphical output some deg left (only PXA LCD). 1501ETEXI 1502 1503DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1504 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1505 " select video card type\n", QEMU_ARCH_ALL) 1506STEXI 1507@item -vga @var{type} 1508@findex -vga 1509Select type of VGA card to emulate. Valid values for @var{type} are 1510@table @option 1511@item cirrus 1512Cirrus Logic GD5446 Video card. All Windows versions starting from 1513Windows 95 should recognize and use this graphic card. For optimal 1514performances, use 16 bit color depth in the guest and the host OS. 1515(This card was the default before QEMU 2.2) 1516@item std 1517Standard VGA card with Bochs VBE extensions. If your guest OS 1518supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1519to use high resolution modes (>= 1280x1024x16) then you should use 1520this option. (This card is the default since QEMU 2.2) 1521@item vmware 1522VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1523recent XFree86/XOrg server or Windows guest with a driver for this 1524card. 1525@item qxl 1526QXL paravirtual graphic card. It is VGA compatible (including VESA 15272.0 VBE support). Works best with qxl guest drivers installed though. 1528Recommended choice when using the spice protocol. 1529@item tcx 1530(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1531sun4m machines and offers both 8-bit and 24-bit colour depths at a 1532fixed resolution of 1024x768. 1533@item cg3 1534(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1535for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1536resolutions aimed at people wishing to run older Solaris versions. 1537@item virtio 1538Virtio VGA card. 1539@item none 1540Disable VGA card. 1541@end table 1542ETEXI 1543 1544DEF("full-screen", 0, QEMU_OPTION_full_screen, 1545 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1546STEXI 1547@item -full-screen 1548@findex -full-screen 1549Start in full screen. 1550ETEXI 1551 1552DEF("g", 1, QEMU_OPTION_g , 1553 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1554 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1555STEXI 1556@item -g @var{width}x@var{height}[x@var{depth}] 1557@findex -g 1558Set the initial graphical resolution and depth (PPC, SPARC only). 1559ETEXI 1560 1561DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1562 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1563STEXI 1564@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1565@findex -vnc 1566Normally, if QEMU is compiled with graphical window support, it displays 1567output such as guest graphics, guest console, and the QEMU monitor in a 1568window. With this option, you can have QEMU listen on VNC display 1569@var{display} and redirect the VGA display over the VNC session. It is 1570very useful to enable the usb tablet device when using this option 1571(option @option{-device usb-tablet}). When using the VNC display, you 1572must use the @option{-k} parameter to set the keyboard layout if you are 1573not using en-us. Valid syntax for the @var{display} is 1574 1575@table @option 1576 1577@item to=@var{L} 1578 1579With this option, QEMU will try next available VNC @var{display}s, until the 1580number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1581available, e.g. port 5900+@var{display} is already used by another 1582application. By default, to=0. 1583 1584@item @var{host}:@var{d} 1585 1586TCP connections will only be allowed from @var{host} on display @var{d}. 1587By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1588be omitted in which case the server will accept connections from any host. 1589 1590@item unix:@var{path} 1591 1592Connections will be allowed over UNIX domain sockets where @var{path} is the 1593location of a unix socket to listen for connections on. 1594 1595@item none 1596 1597VNC is initialized but not started. The monitor @code{change} command 1598can be used to later start the VNC server. 1599 1600@end table 1601 1602Following the @var{display} value there may be one or more @var{option} flags 1603separated by commas. Valid options are 1604 1605@table @option 1606 1607@item reverse 1608 1609Connect to a listening VNC client via a ``reverse'' connection. The 1610client is specified by the @var{display}. For reverse network 1611connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1612is a TCP port number, not a display number. 1613 1614@item websocket 1615 1616Opens an additional TCP listening port dedicated to VNC Websocket connections. 1617If a bare @var{websocket} option is given, the Websocket port is 16185700+@var{display}. An alternative port can be specified with the 1619syntax @code{websocket}=@var{port}. 1620 1621If @var{host} is specified connections will only be allowed from this host. 1622It is possible to control the websocket listen address independently, using 1623the syntax @code{websocket}=@var{host}:@var{port}. 1624 1625If no TLS credentials are provided, the websocket connection runs in 1626unencrypted mode. If TLS credentials are provided, the websocket connection 1627requires encrypted client connections. 1628 1629@item password 1630 1631Require that password based authentication is used for client connections. 1632 1633The password must be set separately using the @code{set_password} command in 1634the @ref{pcsys_monitor}. The syntax to change your password is: 1635@code{set_password <protocol> <password>} where <protocol> could be either 1636"vnc" or "spice". 1637 1638If you would like to change <protocol> password expiration, you should use 1639@code{expire_password <protocol> <expiration-time>} where expiration time could 1640be one of the following options: now, never, +seconds or UNIX time of 1641expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1642to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1643date and time). 1644 1645You can also use keywords "now" or "never" for the expiration time to 1646allow <protocol> password to expire immediately or never expire. 1647 1648@item tls-creds=@var{ID} 1649 1650Provides the ID of a set of TLS credentials to use to secure the 1651VNC server. They will apply to both the normal VNC server socket 1652and the websocket socket (if enabled). Setting TLS credentials 1653will cause the VNC server socket to enable the VeNCrypt auth 1654mechanism. The credentials should have been previously created 1655using the @option{-object tls-creds} argument. 1656 1657The @option{tls-creds} parameter obsoletes the @option{tls}, 1658@option{x509}, and @option{x509verify} options, and as such 1659it is not permitted to set both new and old type options at 1660the same time. 1661 1662@item tls 1663 1664Require that client use TLS when communicating with the VNC server. This 1665uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1666attack. It is recommended that this option be combined with either the 1667@option{x509} or @option{x509verify} options. 1668 1669This option is now deprecated in favor of using the @option{tls-creds} 1670argument. 1671 1672@item x509=@var{/path/to/certificate/dir} 1673 1674Valid if @option{tls} is specified. Require that x509 credentials are used 1675for negotiating the TLS session. The server will send its x509 certificate 1676to the client. It is recommended that a password be set on the VNC server 1677to provide authentication of the client when this is used. The path following 1678this option specifies where the x509 certificates are to be loaded from. 1679See the @ref{vnc_security} section for details on generating certificates. 1680 1681This option is now deprecated in favour of using the @option{tls-creds} 1682argument. 1683 1684@item x509verify=@var{/path/to/certificate/dir} 1685 1686Valid if @option{tls} is specified. Require that x509 credentials are used 1687for negotiating the TLS session. The server will send its x509 certificate 1688to the client, and request that the client send its own x509 certificate. 1689The server will validate the client's certificate against the CA certificate, 1690and reject clients when validation fails. If the certificate authority is 1691trusted, this is a sufficient authentication mechanism. You may still wish 1692to set a password on the VNC server as a second authentication layer. The 1693path following this option specifies where the x509 certificates are to 1694be loaded from. See the @ref{vnc_security} section for details on generating 1695certificates. 1696 1697This option is now deprecated in favour of using the @option{tls-creds} 1698argument. 1699 1700@item sasl 1701 1702Require that the client use SASL to authenticate with the VNC server. 1703The exact choice of authentication method used is controlled from the 1704system / user's SASL configuration file for the 'qemu' service. This 1705is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1706unprivileged user, an environment variable SASL_CONF_PATH can be used 1707to make it search alternate locations for the service config. 1708While some SASL auth methods can also provide data encryption (eg GSSAPI), 1709it is recommended that SASL always be combined with the 'tls' and 1710'x509' settings to enable use of SSL and server certificates. This 1711ensures a data encryption preventing compromise of authentication 1712credentials. See the @ref{vnc_security} section for details on using 1713SASL authentication. 1714 1715@item acl 1716 1717Turn on access control lists for checking of the x509 client certificate 1718and SASL party. For x509 certs, the ACL check is made against the 1719certificate's distinguished name. This is something that looks like 1720@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1721made against the username, which depending on the SASL plugin, may 1722include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1723When the @option{acl} flag is set, the initial access list will be 1724empty, with a @code{deny} policy. Thus no one will be allowed to 1725use the VNC server until the ACLs have been loaded. This can be 1726achieved using the @code{acl} monitor command. 1727 1728@item lossy 1729 1730Enable lossy compression methods (gradient, JPEG, ...). If this 1731option is set, VNC client may receive lossy framebuffer updates 1732depending on its encoding settings. Enabling this option can save 1733a lot of bandwidth at the expense of quality. 1734 1735@item non-adaptive 1736 1737Disable adaptive encodings. Adaptive encodings are enabled by default. 1738An adaptive encoding will try to detect frequently updated screen regions, 1739and send updates in these regions using a lossy encoding (like JPEG). 1740This can be really helpful to save bandwidth when playing videos. Disabling 1741adaptive encodings restores the original static behavior of encodings 1742like Tight. 1743 1744@item share=[allow-exclusive|force-shared|ignore] 1745 1746Set display sharing policy. 'allow-exclusive' allows clients to ask 1747for exclusive access. As suggested by the rfb spec this is 1748implemented by dropping other connections. Connecting multiple 1749clients in parallel requires all clients asking for a shared session 1750(vncviewer: -shared switch). This is the default. 'force-shared' 1751disables exclusive client access. Useful for shared desktop sessions, 1752where you don't want someone forgetting specify -shared disconnect 1753everybody else. 'ignore' completely ignores the shared flag and 1754allows everybody connect unconditionally. Doesn't conform to the rfb 1755spec but is traditional QEMU behavior. 1756 1757@item key-delay-ms 1758 1759Set keyboard delay, for key down and key up events, in milliseconds. 1760Default is 10. Keyboards are low-bandwidth devices, so this slowdown 1761can help the device and guest to keep up and not lose events in case 1762events are arriving in bulk. Possible causes for the latter are flaky 1763network connections, or scripts for automated testing. 1764 1765@end table 1766ETEXI 1767 1768STEXI 1769@end table 1770ETEXI 1771ARCHHEADING(, QEMU_ARCH_I386) 1772 1773ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1774STEXI 1775@table @option 1776ETEXI 1777 1778DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1779 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1780 QEMU_ARCH_I386) 1781STEXI 1782@item -win2k-hack 1783@findex -win2k-hack 1784Use it when installing Windows 2000 to avoid a disk full bug. After 1785Windows 2000 is installed, you no longer need this option (this option 1786slows down the IDE transfers). 1787ETEXI 1788 1789HXCOMM Deprecated by -rtc 1790DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1791 1792DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1793 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1794 QEMU_ARCH_I386) 1795STEXI 1796@item -no-fd-bootchk 1797@findex -no-fd-bootchk 1798Disable boot signature checking for floppy disks in BIOS. May 1799be needed to boot from old floppy disks. 1800ETEXI 1801 1802DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1803 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1804STEXI 1805@item -no-acpi 1806@findex -no-acpi 1807Disable ACPI (Advanced Configuration and Power Interface) support. Use 1808it if your guest OS complains about ACPI problems (PC target machine 1809only). 1810ETEXI 1811 1812DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1813 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1814STEXI 1815@item -no-hpet 1816@findex -no-hpet 1817Disable HPET support. 1818ETEXI 1819 1820DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1821 "-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,{data|file}=file1[:file2]...]\n" 1822 " ACPI table description\n", QEMU_ARCH_I386) 1823STEXI 1824@item -acpitable [sig=@var{str}][,rev=@var{n}][,oem_id=@var{str}][,oem_table_id=@var{str}][,oem_rev=@var{n}] [,asl_compiler_id=@var{str}][,asl_compiler_rev=@var{n}][,data=@var{file1}[:@var{file2}]...] 1825@findex -acpitable 1826Add ACPI table with specified header fields and context from specified files. 1827For file=, take whole ACPI table from the specified files, including all 1828ACPI headers (possible overridden by other options). 1829For data=, only data 1830portion of the table is used, all header information is specified in the 1831command line. 1832If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1833fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1834to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1835spec. 1836ETEXI 1837 1838DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1839 "-smbios file=binary\n" 1840 " load SMBIOS entry from binary file\n" 1841 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1842 " [,uefi=on|off]\n" 1843 " specify SMBIOS type 0 fields\n" 1844 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1845 " [,uuid=uuid][,sku=str][,family=str]\n" 1846 " specify SMBIOS type 1 fields\n" 1847 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1848 " [,asset=str][,location=str]\n" 1849 " specify SMBIOS type 2 fields\n" 1850 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1851 " [,sku=str]\n" 1852 " specify SMBIOS type 3 fields\n" 1853 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1854 " [,asset=str][,part=str]\n" 1855 " specify SMBIOS type 4 fields\n" 1856 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1857 " [,asset=str][,part=str][,speed=%d]\n" 1858 " specify SMBIOS type 17 fields\n", 1859 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1860STEXI 1861@item -smbios file=@var{binary} 1862@findex -smbios 1863Load SMBIOS entry from binary file. 1864 1865@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1866Specify SMBIOS type 0 fields 1867 1868@item -smbios type=1[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,uuid=@var{uuid}][,sku=@var{str}][,family=@var{str}] 1869Specify SMBIOS type 1 fields 1870 1871@item -smbios type=2[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,location=@var{str}][,family=@var{str}] 1872Specify SMBIOS type 2 fields 1873 1874@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1875Specify SMBIOS type 3 fields 1876 1877@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1878Specify SMBIOS type 4 fields 1879 1880@item -smbios type=17[,loc_pfx=@var{str}][,bank=@var{str}][,manufacturer=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}][,speed=@var{%d}] 1881Specify SMBIOS type 17 fields 1882ETEXI 1883 1884STEXI 1885@end table 1886ETEXI 1887DEFHEADING() 1888 1889DEFHEADING(Network options:) 1890STEXI 1891@table @option 1892ETEXI 1893 1894HXCOMM Legacy slirp options (now moved to -net user): 1895#ifdef CONFIG_SLIRP 1896DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1897DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1898DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1899#ifndef _WIN32 1900DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1901#endif 1902#endif 1903 1904DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1905#ifdef CONFIG_SLIRP 1906 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 1907 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 1908 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1909 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n" 1910 " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1911#ifndef _WIN32 1912 "[,smb=dir[,smbserver=addr]]\n" 1913#endif 1914 " configure a user mode network backend with ID 'str',\n" 1915 " its DHCP server and optional services\n" 1916#endif 1917#ifdef _WIN32 1918 "-netdev tap,id=str,ifname=name\n" 1919 " configure a host TAP network backend with ID 'str'\n" 1920#else 1921 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1922 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1923 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1924 " [,poll-us=n]\n" 1925 " configure a host TAP network backend with ID 'str'\n" 1926 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1927 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1928 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1929 " to deconfigure it\n" 1930 " use '[down]script=no' to disable script execution\n" 1931 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1932 " configure it\n" 1933 " use 'fd=h' to connect to an already opened TAP interface\n" 1934 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1935 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1936 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1937 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1938 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1939 " use vhost=on to enable experimental in kernel accelerator\n" 1940 " (only has effect for virtio guests which use MSIX)\n" 1941 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1942 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1943 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1944 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1945 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 1946 " spent on busy polling for vhost net\n" 1947 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1948 " configure a host TAP network backend with ID 'str' that is\n" 1949 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1950 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1951#endif 1952#ifdef __linux__ 1953 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1954 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1955 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1956 " [,rxcookie=rxcookie][,offset=offset]\n" 1957 " configure a network backend with ID 'str' connected to\n" 1958 " an Ethernet over L2TPv3 pseudowire.\n" 1959 " Linux kernel 3.3+ as well as most routers can talk\n" 1960 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1961 " VM to a router and even VM to Host. It is a nearly-universal\n" 1962 " standard (RFC3391). Note - this implementation uses static\n" 1963 " pre-configured tunnels (same as the Linux kernel).\n" 1964 " use 'src=' to specify source address\n" 1965 " use 'dst=' to specify destination address\n" 1966 " use 'udp=on' to specify udp encapsulation\n" 1967 " use 'srcport=' to specify source udp port\n" 1968 " use 'dstport=' to specify destination udp port\n" 1969 " use 'ipv6=on' to force v6\n" 1970 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1971 " well as a weak security measure\n" 1972 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1973 " use 'txcookie=0x012345678' to specify a txcookie\n" 1974 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1975 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1976 " use 'pincounter=on' to work around broken counter handling in peer\n" 1977 " use 'offset=X' to add an extra offset between header and data\n" 1978#endif 1979 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1980 " configure a network backend to connect to another network\n" 1981 " using a socket connection\n" 1982 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1983 " configure a network backend to connect to a multicast maddr and port\n" 1984 " use 'localaddr=addr' to specify the host address to send packets from\n" 1985 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1986 " configure a network backend to connect to another network\n" 1987 " using an UDP tunnel\n" 1988#ifdef CONFIG_VDE 1989 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1990 " configure a network backend to connect to port 'n' of a vde switch\n" 1991 " running on host and listening for incoming connections on 'socketpath'.\n" 1992 " Use group 'groupname' and mode 'octalmode' to change default\n" 1993 " ownership and permissions for communication port.\n" 1994#endif 1995#ifdef CONFIG_NETMAP 1996 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1997 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1998 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1999 " netmap device, defaults to '/dev/netmap')\n" 2000#endif 2001#ifdef CONFIG_POSIX 2002 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 2003 " configure a vhost-user network, backed by a chardev 'dev'\n" 2004#endif 2005 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n" 2006 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL) 2007DEF("nic", HAS_ARG, QEMU_OPTION_nic, 2008 "-nic [tap|bridge|" 2009#ifdef CONFIG_SLIRP 2010 "user|" 2011#endif 2012#ifdef __linux__ 2013 "l2tpv3|" 2014#endif 2015#ifdef CONFIG_VDE 2016 "vde|" 2017#endif 2018#ifdef CONFIG_NETMAP 2019 "netmap|" 2020#endif 2021#ifdef CONFIG_POSIX 2022 "vhost-user|" 2023#endif 2024 "socket][,option][,...][mac=macaddr]\n" 2025 " initialize an on-board / default host NIC (using MAC address\n" 2026 " macaddr) and connect it to the given host network backend\n" 2027 "-nic none use it alone to have zero network devices (the default is to\n" 2028 " provided a 'user' network connection)\n", 2029 QEMU_ARCH_ALL) 2030DEF("net", HAS_ARG, QEMU_OPTION_net, 2031 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 2032 " configure or create an on-board (or machine default) NIC and\n" 2033 " connect it to hub 0 (please use -nic unless you need a hub)\n" 2034 "-net [" 2035#ifdef CONFIG_SLIRP 2036 "user|" 2037#endif 2038 "tap|" 2039 "bridge|" 2040#ifdef CONFIG_VDE 2041 "vde|" 2042#endif 2043#ifdef CONFIG_NETMAP 2044 "netmap|" 2045#endif 2046 "socket][,option][,option][,...]\n" 2047 " old way to initialize a host network interface\n" 2048 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 2049STEXI 2050@item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn] 2051@findex -nic 2052This option is a shortcut for configuring both the on-board (default) guest 2053NIC hardware and the host network backend in one go. The host backend options 2054are the same as with the corresponding @option{-netdev} options below. 2055The guest NIC model can be set with @option{model=@var{modelname}}. 2056Use @option{model=help} to list the available device types. 2057The hardware MAC address can be set with @option{mac=@var{macaddr}}. 2058 2059The following two example do exactly the same, to show how @option{-nic} can 2060be used to shorten the command line length (note that the e1000 is the default 2061on i386, so the @option{model=e1000} parameter could even be omitted here, too): 2062@example 2063qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32 2064qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32 2065@end example 2066 2067@item -nic none 2068Indicate that no network devices should be configured. It is used to override 2069the default configuration (default NIC with ``user'' host network backend) 2070which is activated if no other networking options are provided. 2071 2072@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 2073@findex -netdev 2074Configure user mode host network backend which requires no administrator 2075privilege to run. Valid options are: 2076 2077@table @option 2078@item id=@var{id} 2079Assign symbolic name for use in monitor commands. 2080 2081@item ipv4=on|off and ipv6=on|off 2082Specify that either IPv4 or IPv6 must be enabled. If neither is specified 2083both protocols are enabled. 2084 2085@item net=@var{addr}[/@var{mask}] 2086Set IP network address the guest will see. Optionally specify the netmask, 2087either in the form a.b.c.d or as number of valid top-most bits. Default is 208810.0.2.0/24. 2089 2090@item host=@var{addr} 2091Specify the guest-visible address of the host. Default is the 2nd IP in the 2092guest network, i.e. x.x.x.2. 2093 2094@item ipv6-net=@var{addr}[/@var{int}] 2095Set IPv6 network address the guest will see (default is fec0::/64). The 2096network prefix is given in the usual hexadecimal IPv6 address 2097notation. The prefix size is optional, and is given as the number of 2098valid top-most bits (default is 64). 2099 2100@item ipv6-host=@var{addr} 2101Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 2102the guest network, i.e. xxxx::2. 2103 2104@item restrict=on|off 2105If this option is enabled, the guest will be isolated, i.e. it will not be 2106able to contact the host and no guest IP packets will be routed over the host 2107to the outside. This option does not affect any explicitly set forwarding rules. 2108 2109@item hostname=@var{name} 2110Specifies the client hostname reported by the built-in DHCP server. 2111 2112@item dhcpstart=@var{addr} 2113Specify the first of the 16 IPs the built-in DHCP server can assign. Default 2114is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 2115 2116@item dns=@var{addr} 2117Specify the guest-visible address of the virtual nameserver. The address must 2118be different from the host address. Default is the 3rd IP in the guest network, 2119i.e. x.x.x.3. 2120 2121@item ipv6-dns=@var{addr} 2122Specify the guest-visible address of the IPv6 virtual nameserver. The address 2123must be different from the host address. Default is the 3rd IP in the guest 2124network, i.e. xxxx::3. 2125 2126@item dnssearch=@var{domain} 2127Provides an entry for the domain-search list sent by the built-in 2128DHCP server. More than one domain suffix can be transmitted by specifying 2129this option multiple times. If supported, this will cause the guest to 2130automatically try to append the given domain suffix(es) in case a domain name 2131can not be resolved. 2132 2133Example: 2134@example 2135qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org 2136@end example 2137 2138@item domainname=@var{domain} 2139Specifies the client domain name reported by the built-in DHCP server. 2140 2141@item tftp=@var{dir} 2142When using the user mode network stack, activate a built-in TFTP 2143server. The files in @var{dir} will be exposed as the root of a TFTP server. 2144The TFTP client on the guest must be configured in binary mode (use the command 2145@code{bin} of the Unix TFTP client). 2146 2147@item bootfile=@var{file} 2148When using the user mode network stack, broadcast @var{file} as the BOOTP 2149filename. In conjunction with @option{tftp}, this can be used to network boot 2150a guest from a local directory. 2151 2152Example (using pxelinux): 2153@example 2154qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \ 2155 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2156@end example 2157 2158@item smb=@var{dir}[,smbserver=@var{addr}] 2159When using the user mode network stack, activate a built-in SMB 2160server so that Windows OSes can access to the host files in @file{@var{dir}} 2161transparently. The IP address of the SMB server can be set to @var{addr}. By 2162default the 4th IP in the guest network is used, i.e. x.x.x.4. 2163 2164In the guest Windows OS, the line: 2165@example 216610.0.2.4 smbserver 2167@end example 2168must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2169or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2170 2171Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2172 2173Note that a SAMBA server must be installed on the host OS. 2174 2175@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2176Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2177the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2178@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2179given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2180be bound to a specific host interface. If no connection type is set, TCP is 2181used. This option can be given multiple times. 2182 2183For example, to redirect host X11 connection from screen 1 to guest 2184screen 0, use the following: 2185 2186@example 2187# on the host 2188qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 2189# this host xterm should open in the guest X11 server 2190xterm -display :1 2191@end example 2192 2193To redirect telnet connections from host port 5555 to telnet port on 2194the guest, use the following: 2195 2196@example 2197# on the host 2198qemu-system-i386 -nic user,hostfwd=tcp::5555-:23 2199telnet localhost 5555 2200@end example 2201 2202Then when you use on the host @code{telnet localhost 5555}, you 2203connect to the guest telnet server. 2204 2205@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2206@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2207Forward guest TCP connections to the IP address @var{server} on port @var{port} 2208to the character device @var{dev} or to a program executed by @var{cmd:command} 2209which gets spawned for each connection. This option can be given multiple times. 2210 2211You can either use a chardev directly and have that one used throughout QEMU's 2212lifetime, like in the following example: 2213 2214@example 2215# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2216# the guest accesses it 2217qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 2218@end example 2219 2220Or you can execute a command on every TCP connection established by the guest, 2221so that QEMU behaves similar to an inetd process for that virtual server: 2222 2223@example 2224# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2225# and connect the TCP stream to its stdin/stdout 2226qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2227@end example 2228 2229@end table 2230 2231Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 2232processed and applied to -net user. Mixing them with the new configuration 2233syntax gives undefined results. Their use for new applications is discouraged 2234as they will be removed from future versions. 2235 2236@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2237Configure a host TAP network backend with ID @var{id}. 2238 2239Use the network script @var{file} to configure it and the network script 2240@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2241automatically provides one. The default network configure script is 2242@file{/etc/qemu-ifup} and the default network deconfigure script is 2243@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2244to disable script execution. 2245 2246If running QEMU as an unprivileged user, use the network helper 2247@var{helper} to configure the TAP interface and attach it to the bridge. 2248The default network helper executable is @file{/path/to/qemu-bridge-helper} 2249and the default bridge device is @file{br0}. 2250 2251@option{fd}=@var{h} can be used to specify the handle of an already 2252opened host TAP interface. 2253 2254Examples: 2255 2256@example 2257#launch a QEMU instance with the default network script 2258qemu-system-i386 linux.img -nic tap 2259@end example 2260 2261@example 2262#launch a QEMU instance with two NICs, each one connected 2263#to a TAP device 2264qemu-system-i386 linux.img \ 2265 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \ 2266 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1 2267@end example 2268 2269@example 2270#launch a QEMU instance with the default network helper to 2271#connect a TAP device to bridge br0 2272qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \ 2273 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper" 2274@end example 2275 2276@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2277Connect a host TAP network interface to a host bridge device. 2278 2279Use the network helper @var{helper} to configure the TAP interface and 2280attach it to the bridge. The default network helper executable is 2281@file{/path/to/qemu-bridge-helper} and the default bridge 2282device is @file{br0}. 2283 2284Examples: 2285 2286@example 2287#launch a QEMU instance with the default network helper to 2288#connect a TAP device to bridge br0 2289qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1 2290@end example 2291 2292@example 2293#launch a QEMU instance with the default network helper to 2294#connect a TAP device to bridge qemubr0 2295qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1 2296@end example 2297 2298@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2299 2300This host network backend can be used to connect the guest's network to 2301another QEMU virtual machine using a TCP socket connection. If @option{listen} 2302is specified, QEMU waits for incoming connections on @var{port} 2303(@var{host} is optional). @option{connect} is used to connect to 2304another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2305specifies an already opened TCP socket. 2306 2307Example: 2308@example 2309# launch a first QEMU instance 2310qemu-system-i386 linux.img \ 2311 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2312 -netdev socket,id=n1,listen=:1234 2313# connect the network of this instance to the network of the first instance 2314qemu-system-i386 linux.img \ 2315 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2316 -netdev socket,id=n2,connect=127.0.0.1:1234 2317@end example 2318 2319@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2320 2321Configure a socket host network backend to share the guest's network traffic 2322with another QEMU virtual machines using a UDP multicast socket, effectively 2323making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. 2324NOTES: 2325@enumerate 2326@item 2327Several QEMU can be running on different hosts and share same bus (assuming 2328correct multicast setup for these hosts). 2329@item 2330mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2331@url{http://user-mode-linux.sf.net}. 2332@item 2333Use @option{fd=h} to specify an already opened UDP multicast socket. 2334@end enumerate 2335 2336Example: 2337@example 2338# launch one QEMU instance 2339qemu-system-i386 linux.img \ 2340 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2341 -netdev socket,id=n1,mcast=230.0.0.1:1234 2342# launch another QEMU instance on same "bus" 2343qemu-system-i386 linux.img \ 2344 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2345 -netdev socket,id=n2,mcast=230.0.0.1:1234 2346# launch yet another QEMU instance on same "bus" 2347qemu-system-i386 linux.img \ 2348 -device e1000,netdev=n3,macaddr=52:54:00:12:34:58 \ 2349 -netdev socket,id=n3,mcast=230.0.0.1:1234 2350@end example 2351 2352Example (User Mode Linux compat.): 2353@example 2354# launch QEMU instance (note mcast address selected is UML's default) 2355qemu-system-i386 linux.img \ 2356 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2357 -netdev socket,id=n1,mcast=239.192.168.1:1102 2358# launch UML 2359/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2360@end example 2361 2362Example (send packets from host's 1.2.3.4): 2363@example 2364qemu-system-i386 linux.img \ 2365 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2366 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2367@end example 2368 2369@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}] 2370Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a 2371popular protocol to transport Ethernet (and other Layer 2) data frames between 2372two systems. It is present in routers, firewalls and the Linux kernel 2373(from version 3.3 onwards). 2374 2375This transport allows a VM to communicate to another VM, router or firewall directly. 2376 2377@table @option 2378@item src=@var{srcaddr} 2379 source address (mandatory) 2380@item dst=@var{dstaddr} 2381 destination address (mandatory) 2382@item udp 2383 select udp encapsulation (default is ip). 2384@item srcport=@var{srcport} 2385 source udp port. 2386@item dstport=@var{dstport} 2387 destination udp port. 2388@item ipv6 2389 force v6, otherwise defaults to v4. 2390@item rxcookie=@var{rxcookie} 2391@itemx txcookie=@var{txcookie} 2392 Cookies are a weak form of security in the l2tpv3 specification. 2393Their function is mostly to prevent misconfiguration. By default they are 32 2394bit. 2395@item cookie64 2396 Set cookie size to 64 bit instead of the default 32 2397@item counter=off 2398 Force a 'cut-down' L2TPv3 with no counter as in 2399draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2400@item pincounter=on 2401 Work around broken counter handling in peer. This may also help on 2402networks which have packet reorder. 2403@item offset=@var{offset} 2404 Add an extra offset between header and data 2405@end table 2406 2407For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2408on the remote Linux host 1.2.3.4: 2409@example 2410# Setup tunnel on linux host using raw ip as encapsulation 2411# on 1.2.3.4 2412ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2413 encap udp udp_sport 16384 udp_dport 16384 2414ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2415 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2416ifconfig vmtunnel0 mtu 1500 2417ifconfig vmtunnel0 up 2418brctl addif br-lan vmtunnel0 2419 2420 2421# on 4.3.2.1 2422# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2423 2424qemu-system-i386 linux.img -device e1000,netdev=n1 \ 2425 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2426 2427@end example 2428 2429@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2430Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and 2431listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2432and MODE @var{octalmode} to change default ownership and permissions for 2433communication port. This option is only available if QEMU has been compiled 2434with vde support enabled. 2435 2436Example: 2437@example 2438# launch vde switch 2439vde_switch -F -sock /tmp/myswitch 2440# launch QEMU instance 2441qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch 2442@end example 2443 2444@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2445 2446Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2447be a unix domain socket backed one. The vhost-user uses a specifically defined 2448protocol to pass vhost ioctl replacement messages to an application on the other 2449end of the socket. On non-MSIX guests, the feature can be forced with 2450@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2451be created for multiqueue vhost-user. 2452 2453Example: 2454@example 2455qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2456 -numa node,memdev=mem \ 2457 -chardev socket,id=chr0,path=/path/to/socket \ 2458 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2459 -device virtio-net-pci,netdev=net0 2460@end example 2461 2462@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}] 2463 2464Create a hub port on the emulated hub with ID @var{hubid}. 2465 2466The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a 2467single netdev. Alternatively, you can also connect the hubport to another 2468netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option. 2469 2470@item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2471@findex -net 2472Legacy option to configure or create an on-board (or machine default) Network 2473Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. 2474the default hub), or to the netdev @var{nd}. 2475The NIC is an e1000 by default on the PC target. Optionally, the MAC address 2476can be changed to @var{mac}, the device address set to @var{addr} (PCI cards 2477only), and a @var{name} can be assigned for use in monitor commands. 2478Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2479that the card should have; this option currently only affects virtio cards; set 2480@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2481NIC is created. QEMU can emulate several different models of network card. 2482Use @code{-net nic,model=help} for a list of available devices for your target. 2483 2484@item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}] 2485Configure a host network backend (with the options corresponding to the same 2486@option{-netdev} option) and connect it to the emulated hub 0 (the default 2487hub). Use @var{name} to specify the name of the hub port. 2488ETEXI 2489 2490STEXI 2491@end table 2492ETEXI 2493DEFHEADING() 2494 2495DEFHEADING(Character device options:) 2496 2497DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2498 "-chardev help\n" 2499 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2500 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2501 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n" 2502 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2503 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n" 2504 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2505 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2506 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2507 " [,logfile=PATH][,logappend=on|off]\n" 2508 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2509 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2510 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2511 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2512 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2513 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2514#ifdef _WIN32 2515 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2516 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2517#else 2518 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2519 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2520#endif 2521#ifdef CONFIG_BRLAPI 2522 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2523#endif 2524#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2525 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2526 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2527 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2528#endif 2529#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2530 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2531 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2532#endif 2533#if defined(CONFIG_SPICE) 2534 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2535 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2536#endif 2537 , QEMU_ARCH_ALL 2538) 2539 2540STEXI 2541 2542The general form of a character device option is: 2543@table @option 2544@item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}] 2545@findex -chardev 2546Backend is one of: 2547@option{null}, 2548@option{socket}, 2549@option{udp}, 2550@option{msmouse}, 2551@option{vc}, 2552@option{ringbuf}, 2553@option{file}, 2554@option{pipe}, 2555@option{console}, 2556@option{serial}, 2557@option{pty}, 2558@option{stdio}, 2559@option{braille}, 2560@option{tty}, 2561@option{parallel}, 2562@option{parport}, 2563@option{spicevmc}, 2564@option{spiceport}. 2565The specific backend will determine the applicable options. 2566 2567Use @code{-chardev help} to print all available chardev backend types. 2568 2569All devices must have an id, which can be any string up to 127 characters long. 2570It is used to uniquely identify this device in other command line directives. 2571 2572A character device may be used in multiplexing mode by multiple front-ends. 2573Specify @option{mux=on} to enable this mode. 2574A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2575backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2576If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2577create a multiplexer with your specified ID, and you can then configure multiple 2578front ends to use that chardev ID for their input/output. Up to four different 2579front ends can be connected to a single multiplexed chardev. (Without 2580multiplexing enabled, a chardev can only be used by a single front end.) 2581For instance you could use this to allow a single stdio chardev to be used by 2582two serial ports and the QEMU monitor: 2583 2584@example 2585-chardev stdio,mux=on,id=char0 \ 2586-mon chardev=char0,mode=readline \ 2587-serial chardev:char0 \ 2588-serial chardev:char0 2589@end example 2590 2591You can have more than one multiplexer in a system configuration; for instance 2592you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2593multiplexed between the QEMU monitor and a parallel port: 2594 2595@example 2596-chardev stdio,mux=on,id=char0 \ 2597-mon chardev=char0,mode=readline \ 2598-parallel chardev:char0 \ 2599-chardev tcp,...,mux=on,id=char1 \ 2600-serial chardev:char1 \ 2601-serial chardev:char1 2602@end example 2603 2604When you're using a multiplexed character device, some escape sequences are 2605interpreted in the input. @xref{mux_keys, Keys in the character backend 2606multiplexer}. 2607 2608Note that some other command line options may implicitly create multiplexed 2609character backends; for instance @option{-serial mon:stdio} creates a 2610multiplexed stdio backend connected to the serial port and the QEMU monitor, 2611and @option{-nographic} also multiplexes the console and the monitor to 2612stdio. 2613 2614There is currently no support for multiplexing in the other direction 2615(where a single QEMU front end takes input and output from multiple chardevs). 2616 2617Every backend supports the @option{logfile} option, which supplies the path 2618to a file to record all data transmitted via the backend. The @option{logappend} 2619option controls whether the log file will be truncated or appended to when 2620opened. 2621 2622@end table 2623 2624The available backends are: 2625 2626@table @option 2627@item -chardev null,id=@var{id} 2628A void device. This device will not emit any data, and will drop any data it 2629receives. The null backend does not take any options. 2630 2631@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,reconnect=@var{seconds}][,tls-creds=@var{id}] 2632 2633Create a two-way stream socket, which can be either a TCP or a unix socket. A 2634unix socket will be created if @option{path} is specified. Behaviour is 2635undefined if TCP options are specified for a unix socket. 2636 2637@option{server} specifies that the socket shall be a listening socket. 2638 2639@option{nowait} specifies that QEMU should not block waiting for a client to 2640connect to a listening socket. 2641 2642@option{telnet} specifies that traffic on the socket should interpret telnet 2643escape sequences. 2644 2645@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2646the remote end goes away. qemu will delay this many seconds and then attempt 2647to reconnect. Zero disables reconnecting, and is the default. 2648 2649@option{tls-creds} requests enablement of the TLS protocol for encryption, 2650and specifies the id of the TLS credentials to use for the handshake. The 2651credentials must be previously created with the @option{-object tls-creds} 2652argument. 2653 2654TCP and unix socket options are given below: 2655 2656@table @option 2657 2658@item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay] 2659 2660@option{host} for a listening socket specifies the local address to be bound. 2661For a connecting socket species the remote host to connect to. @option{host} is 2662optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2663 2664@option{port} for a listening socket specifies the local port to be bound. For a 2665connecting socket specifies the port on the remote host to connect to. 2666@option{port} can be given as either a port number or a service name. 2667@option{port} is required. 2668 2669@option{to} is only relevant to listening sockets. If it is specified, and 2670@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2671to and including @option{to} until it succeeds. @option{to} must be specified 2672as a port number. 2673 2674@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2675If neither is specified the socket may use either protocol. 2676 2677@option{nodelay} disables the Nagle algorithm. 2678 2679@item unix options: path=@var{path} 2680 2681@option{path} specifies the local path of the unix socket. @option{path} is 2682required. 2683 2684@end table 2685 2686@item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6] 2687 2688Sends all traffic from the guest to a remote host over UDP. 2689 2690@option{host} specifies the remote host to connect to. If not specified it 2691defaults to @code{localhost}. 2692 2693@option{port} specifies the port on the remote host to connect to. @option{port} 2694is required. 2695 2696@option{localaddr} specifies the local address to bind to. If not specified it 2697defaults to @code{0.0.0.0}. 2698 2699@option{localport} specifies the local port to bind to. If not specified any 2700available local port will be used. 2701 2702@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2703If neither is specified the device may use either protocol. 2704 2705@item -chardev msmouse,id=@var{id} 2706 2707Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2708take any options. 2709 2710@item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]] 2711 2712Connect to a QEMU text console. @option{vc} may optionally be given a specific 2713size. 2714 2715@option{width} and @option{height} specify the width and height respectively of 2716the console, in pixels. 2717 2718@option{cols} and @option{rows} specify that the console be sized to fit a text 2719console with the given dimensions. 2720 2721@item -chardev ringbuf,id=@var{id}[,size=@var{size}] 2722 2723Create a ring buffer with fixed size @option{size}. 2724@var{size} must be a power of two and defaults to @code{64K}. 2725 2726@item -chardev file,id=@var{id},path=@var{path} 2727 2728Log all traffic received from the guest to a file. 2729 2730@option{path} specifies the path of the file to be opened. This file will be 2731created if it does not already exist, and overwritten if it does. @option{path} 2732is required. 2733 2734@item -chardev pipe,id=@var{id},path=@var{path} 2735 2736Create a two-way connection to the guest. The behaviour differs slightly between 2737Windows hosts and other hosts: 2738 2739On Windows, a single duplex pipe will be created at 2740@file{\\.pipe\@option{path}}. 2741 2742On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2743@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2744received by the guest. Data written by the guest can be read from 2745@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2746be present. 2747 2748@option{path} forms part of the pipe path as described above. @option{path} is 2749required. 2750 2751@item -chardev console,id=@var{id} 2752 2753Send traffic from the guest to QEMU's standard output. @option{console} does not 2754take any options. 2755 2756@option{console} is only available on Windows hosts. 2757 2758@item -chardev serial,id=@var{id},path=@option{path} 2759 2760Send traffic from the guest to a serial device on the host. 2761 2762On Unix hosts serial will actually accept any tty device, 2763not only serial lines. 2764 2765@option{path} specifies the name of the serial device to open. 2766 2767@item -chardev pty,id=@var{id} 2768 2769Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2770not take any options. 2771 2772@option{pty} is not available on Windows hosts. 2773 2774@item -chardev stdio,id=@var{id}[,signal=on|off] 2775Connect to standard input and standard output of the QEMU process. 2776 2777@option{signal} controls if signals are enabled on the terminal, that includes 2778exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2779default, use @option{signal=off} to disable it. 2780 2781@item -chardev braille,id=@var{id} 2782 2783Connect to a local BrlAPI server. @option{braille} does not take any options. 2784 2785@item -chardev tty,id=@var{id},path=@var{path} 2786 2787@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2788DragonFlyBSD hosts. It is an alias for @option{serial}. 2789 2790@option{path} specifies the path to the tty. @option{path} is required. 2791 2792@item -chardev parallel,id=@var{id},path=@var{path} 2793@itemx -chardev parport,id=@var{id},path=@var{path} 2794 2795@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2796 2797Connect to a local parallel port. 2798 2799@option{path} specifies the path to the parallel port device. @option{path} is 2800required. 2801 2802@item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name} 2803 2804@option{spicevmc} is only available when spice support is built in. 2805 2806@option{debug} debug level for spicevmc 2807 2808@option{name} name of spice channel to connect to 2809 2810Connect to a spice virtual machine channel, such as vdiport. 2811 2812@item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name} 2813 2814@option{spiceport} is only available when spice support is built in. 2815 2816@option{debug} debug level for spicevmc 2817 2818@option{name} name of spice port to connect to 2819 2820Connect to a spice port, allowing a Spice client to handle the traffic 2821identified by a name (preferably a fqdn). 2822ETEXI 2823 2824STEXI 2825@end table 2826ETEXI 2827DEFHEADING() 2828 2829DEFHEADING(Bluetooth(R) options:) 2830STEXI 2831@table @option 2832ETEXI 2833 2834DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2835 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2836 "-bt hci,host[:id]\n" \ 2837 " use host's HCI with the given name\n" \ 2838 "-bt hci[,vlan=n]\n" \ 2839 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2840 "-bt vhci[,vlan=n]\n" \ 2841 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2842 "-bt device:dev[,vlan=n]\n" \ 2843 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2844 QEMU_ARCH_ALL) 2845STEXI 2846@item -bt hci[...] 2847@findex -bt 2848Defines the function of the corresponding Bluetooth HCI. -bt options 2849are matched with the HCIs present in the chosen machine type. For 2850example when emulating a machine with only one HCI built into it, only 2851the first @code{-bt hci[...]} option is valid and defines the HCI's 2852logic. The Transport Layer is decided by the machine type. Currently 2853the machines @code{n800} and @code{n810} have one HCI and all other 2854machines have none. 2855 2856@anchor{bt-hcis} 2857The following three types are recognized: 2858 2859@table @option 2860@item -bt hci,null 2861(default) The corresponding Bluetooth HCI assumes no internal logic 2862and will not respond to any HCI commands or emit events. 2863 2864@item -bt hci,host[:@var{id}] 2865(@code{bluez} only) The corresponding HCI passes commands / events 2866to / from the physical HCI identified by the name @var{id} (default: 2867@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2868capable systems like Linux. 2869 2870@item -bt hci[,vlan=@var{n}] 2871Add a virtual, standard HCI that will participate in the Bluetooth 2872scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2873VLANs, devices inside a bluetooth network @var{n} can only communicate 2874with other devices in the same network (scatternet). 2875@end table 2876 2877@item -bt vhci[,vlan=@var{n}] 2878(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2879to the host bluetooth stack instead of to the emulated target. This 2880allows the host and target machines to participate in a common scatternet 2881and communicate. Requires the Linux @code{vhci} driver installed. Can 2882be used as following: 2883 2884@example 2885qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2886@end example 2887 2888@item -bt device:@var{dev}[,vlan=@var{n}] 2889Emulate a bluetooth device @var{dev} and place it in network @var{n} 2890(default @code{0}). QEMU can only emulate one type of bluetooth devices 2891currently: 2892 2893@table @option 2894@item keyboard 2895Virtual wireless keyboard implementing the HIDP bluetooth profile. 2896@end table 2897ETEXI 2898 2899STEXI 2900@end table 2901ETEXI 2902DEFHEADING() 2903 2904#ifdef CONFIG_TPM 2905DEFHEADING(TPM device options:) 2906 2907DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2908 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2909 " use path to provide path to a character device; default is /dev/tpm0\n" 2910 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2911 " not provided it will be searched for in /sys/class/misc/tpm?/device\n" 2912 "-tpmdev emulator,id=id,chardev=dev\n" 2913 " configure the TPM device using chardev backend\n", 2914 QEMU_ARCH_ALL) 2915STEXI 2916 2917The general form of a TPM device option is: 2918@table @option 2919 2920@item -tpmdev @var{backend},id=@var{id}[,@var{options}] 2921@findex -tpmdev 2922 2923The specific backend type will determine the applicable options. 2924The @code{-tpmdev} option creates the TPM backend and requires a 2925@code{-device} option that specifies the TPM frontend interface model. 2926 2927Use @code{-tpmdev help} to print all available TPM backend types. 2928 2929@end table 2930 2931The available backends are: 2932 2933@table @option 2934 2935@item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path} 2936 2937(Linux-host only) Enable access to the host's TPM using the passthrough 2938driver. 2939 2940@option{path} specifies the path to the host's TPM device, i.e., on 2941a Linux host this would be @code{/dev/tpm0}. 2942@option{path} is optional and by default @code{/dev/tpm0} is used. 2943 2944@option{cancel-path} specifies the path to the host TPM device's sysfs 2945entry allowing for cancellation of an ongoing TPM command. 2946@option{cancel-path} is optional and by default QEMU will search for the 2947sysfs entry to use. 2948 2949Some notes about using the host's TPM with the passthrough driver: 2950 2951The TPM device accessed by the passthrough driver must not be 2952used by any other application on the host. 2953 2954Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2955the VM's firmware (BIOS/UEFI) will not be able to initialize the 2956TPM again and may therefore not show a TPM-specific menu that would 2957otherwise allow the user to configure the TPM, e.g., allow the user to 2958enable/disable or activate/deactivate the TPM. 2959Further, if TPM ownership is released from within a VM then the host's TPM 2960will get disabled and deactivated. To enable and activate the 2961TPM again afterwards, the host has to be rebooted and the user is 2962required to enter the firmware's menu to enable and activate the TPM. 2963If the TPM is left disabled and/or deactivated most TPM commands will fail. 2964 2965To create a passthrough TPM use the following two options: 2966@example 2967-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2968@end example 2969Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2970@code{tpmdev=tpm0} in the device option. 2971 2972@item -tpmdev emulator,id=@var{id},chardev=@var{dev} 2973 2974(Linux-host only) Enable access to a TPM emulator using Unix domain socket based 2975chardev backend. 2976 2977@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server. 2978 2979To create a TPM emulator backend device with chardev socket backend: 2980@example 2981 2982-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0 2983 2984@end example 2985 2986ETEXI 2987 2988STEXI 2989@end table 2990ETEXI 2991DEFHEADING() 2992 2993#endif 2994 2995DEFHEADING(Linux/Multiboot boot specific:) 2996STEXI 2997 2998When using these options, you can use a given Linux or Multiboot 2999kernel without installing it in the disk image. It can be useful 3000for easier testing of various kernels. 3001 3002@table @option 3003ETEXI 3004 3005DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 3006 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 3007STEXI 3008@item -kernel @var{bzImage} 3009@findex -kernel 3010Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 3011or in multiboot format. 3012ETEXI 3013 3014DEF("append", HAS_ARG, QEMU_OPTION_append, \ 3015 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 3016STEXI 3017@item -append @var{cmdline} 3018@findex -append 3019Use @var{cmdline} as kernel command line 3020ETEXI 3021 3022DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 3023 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 3024STEXI 3025@item -initrd @var{file} 3026@findex -initrd 3027Use @var{file} as initial ram disk. 3028 3029@item -initrd "@var{file1} arg=foo,@var{file2}" 3030 3031This syntax is only available with multiboot. 3032 3033Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 3034first module. 3035ETEXI 3036 3037DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 3038 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 3039STEXI 3040@item -dtb @var{file} 3041@findex -dtb 3042Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 3043on boot. 3044ETEXI 3045 3046STEXI 3047@end table 3048ETEXI 3049DEFHEADING() 3050 3051DEFHEADING(Debug/Expert options:) 3052STEXI 3053@table @option 3054ETEXI 3055 3056DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 3057 "-fw_cfg [name=]<name>,file=<file>\n" 3058 " add named fw_cfg entry with contents from file\n" 3059 "-fw_cfg [name=]<name>,string=<str>\n" 3060 " add named fw_cfg entry with contents from string\n", 3061 QEMU_ARCH_ALL) 3062STEXI 3063 3064@item -fw_cfg [name=]@var{name},file=@var{file} 3065@findex -fw_cfg 3066Add named fw_cfg entry with contents from file @var{file}. 3067 3068@item -fw_cfg [name=]@var{name},string=@var{str} 3069Add named fw_cfg entry with contents from string @var{str}. 3070 3071The terminating NUL character of the contents of @var{str} will not be 3072included as part of the fw_cfg item data. To insert contents with 3073embedded NUL characters, you have to use the @var{file} parameter. 3074 3075The fw_cfg entries are passed by QEMU through to the guest. 3076 3077Example: 3078@example 3079 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 3080@end example 3081creates an fw_cfg entry named opt/com.mycompany/blob with contents 3082from ./my_blob.bin. 3083 3084ETEXI 3085 3086DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 3087 "-serial dev redirect the serial port to char device 'dev'\n", 3088 QEMU_ARCH_ALL) 3089STEXI 3090@item -serial @var{dev} 3091@findex -serial 3092Redirect the virtual serial port to host character device 3093@var{dev}. The default device is @code{vc} in graphical mode and 3094@code{stdio} in non graphical mode. 3095 3096This option can be used several times to simulate up to 4 serial 3097ports. 3098 3099Use @code{-serial none} to disable all serial ports. 3100 3101Available character devices are: 3102@table @option 3103@item vc[:@var{W}x@var{H}] 3104Virtual console. Optionally, a width and height can be given in pixel with 3105@example 3106vc:800x600 3107@end example 3108It is also possible to specify width or height in characters: 3109@example 3110vc:80Cx24C 3111@end example 3112@item pty 3113[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3114@item none 3115No device is allocated. 3116@item null 3117void device 3118@item chardev:@var{id} 3119Use a named character device defined with the @code{-chardev} option. 3120@item /dev/XXX 3121[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3122parameters are set according to the emulated ones. 3123@item /dev/parport@var{N} 3124[Linux only, parallel port only] Use host parallel port 3125@var{N}. Currently SPP and EPP parallel port features can be used. 3126@item file:@var{filename} 3127Write output to @var{filename}. No character can be read. 3128@item stdio 3129[Unix only] standard input/output 3130@item pipe:@var{filename} 3131name pipe @var{filename} 3132@item COM@var{n} 3133[Windows only] Use host serial port @var{n} 3134@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3135This implements UDP Net Console. 3136When @var{remote_host} or @var{src_ip} are not specified 3137they default to @code{0.0.0.0}. 3138When not using a specified @var{src_port} a random port is automatically chosen. 3139 3140If you just want a simple readonly console you can use @code{netcat} or 3141@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3142@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3143will appear in the netconsole session. 3144 3145If you plan to send characters back via netconsole or you want to stop 3146and start QEMU a lot of times, you should have QEMU use the same 3147source port each time by using something like @code{-serial 3148udp::4555@@:4556} to QEMU. Another approach is to use a patched 3149version of netcat which can listen to a TCP port and send and receive 3150characters via udp. If you have a patched version of netcat which 3151activates telnet remote echo and single char transfer, then you can 3152use the following options to set up a netcat redirector to allow 3153telnet on port 5555 to access the QEMU port. 3154@table @code 3155@item QEMU Options: 3156-serial udp::4555@@:4556 3157@item netcat options: 3158-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3159@item telnet options: 3160localhost 5555 3161@end table 3162 3163@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3164The TCP Net Console has two modes of operation. It can send the serial 3165I/O to a location or wait for a connection from a location. By default 3166the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3167the @var{server} option QEMU will wait for a client socket application 3168to connect to the port before continuing, unless the @code{nowait} 3169option was specified. The @code{nodelay} option disables the Nagle buffering 3170algorithm. The @code{reconnect} option only applies if @var{noserver} is 3171set, if the connection goes down it will attempt to reconnect at the 3172given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3173one TCP connection at a time is accepted. You can use @code{telnet} to 3174connect to the corresponding character device. 3175@table @code 3176@item Example to send tcp console to 192.168.0.2 port 4444 3177-serial tcp:192.168.0.2:4444 3178@item Example to listen and wait on port 4444 for connection 3179-serial tcp::4444,server 3180@item Example to not wait and listen on ip 192.168.0.100 port 4444 3181-serial tcp:192.168.0.100:4444,server,nowait 3182@end table 3183 3184@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3185The telnet protocol is used instead of raw tcp sockets. The options 3186work the same as if you had specified @code{-serial tcp}. The 3187difference is that the port acts like a telnet server or client using 3188telnet option negotiation. This will also allow you to send the 3189MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3190sequence. Typically in unix telnet you do it with Control-] and then 3191type "send break" followed by pressing the enter key. 3192 3193@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3194A unix domain socket is used instead of a tcp socket. The option works the 3195same as if you had specified @code{-serial tcp} except the unix domain socket 3196@var{path} is used for connections. 3197 3198@item mon:@var{dev_string} 3199This is a special option to allow the monitor to be multiplexed onto 3200another serial port. The monitor is accessed with key sequence of 3201@key{Control-a} and then pressing @key{c}. 3202@var{dev_string} should be any one of the serial devices specified 3203above. An example to multiplex the monitor onto a telnet server 3204listening on port 4444 would be: 3205@table @code 3206@item -serial mon:telnet::4444,server,nowait 3207@end table 3208When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3209QEMU any more but will be passed to the guest instead. 3210 3211@item braille 3212Braille device. This will use BrlAPI to display the braille output on a real 3213or fake device. 3214 3215@item msmouse 3216Three button serial mouse. Configure the guest to use Microsoft protocol. 3217@end table 3218ETEXI 3219 3220DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3221 "-parallel dev redirect the parallel port to char device 'dev'\n", 3222 QEMU_ARCH_ALL) 3223STEXI 3224@item -parallel @var{dev} 3225@findex -parallel 3226Redirect the virtual parallel port to host device @var{dev} (same 3227devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3228be used to use hardware devices connected on the corresponding host 3229parallel port. 3230 3231This option can be used several times to simulate up to 3 parallel 3232ports. 3233 3234Use @code{-parallel none} to disable all parallel ports. 3235ETEXI 3236 3237DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3238 "-monitor dev redirect the monitor to char device 'dev'\n", 3239 QEMU_ARCH_ALL) 3240STEXI 3241@item -monitor @var{dev} 3242@findex -monitor 3243Redirect the monitor to host device @var{dev} (same devices as the 3244serial port). 3245The default device is @code{vc} in graphical mode and @code{stdio} in 3246non graphical mode. 3247Use @code{-monitor none} to disable the default monitor. 3248ETEXI 3249DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3250 "-qmp dev like -monitor but opens in 'control' mode\n", 3251 QEMU_ARCH_ALL) 3252STEXI 3253@item -qmp @var{dev} 3254@findex -qmp 3255Like -monitor but opens in 'control' mode. 3256ETEXI 3257DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3258 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3259 QEMU_ARCH_ALL) 3260STEXI 3261@item -qmp-pretty @var{dev} 3262@findex -qmp-pretty 3263Like -qmp but uses pretty JSON formatting. 3264ETEXI 3265 3266DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3267 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL) 3268STEXI 3269@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]] 3270@findex -mon 3271Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing 3272easing human reading and debugging. 3273ETEXI 3274 3275DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3276 "-debugcon dev redirect the debug console to char device 'dev'\n", 3277 QEMU_ARCH_ALL) 3278STEXI 3279@item -debugcon @var{dev} 3280@findex -debugcon 3281Redirect the debug console to host device @var{dev} (same devices as the 3282serial port). The debug console is an I/O port which is typically port 32830xe9; writing to that I/O port sends output to this device. 3284The default device is @code{vc} in graphical mode and @code{stdio} in 3285non graphical mode. 3286ETEXI 3287 3288DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3289 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3290STEXI 3291@item -pidfile @var{file} 3292@findex -pidfile 3293Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3294from a script. 3295ETEXI 3296 3297DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3298 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3299STEXI 3300@item -singlestep 3301@findex -singlestep 3302Run the emulation in single step mode. 3303ETEXI 3304 3305DEF("preconfig", 0, QEMU_OPTION_preconfig, \ 3306 "--preconfig pause QEMU before machine is initialized (experimental)\n", 3307 QEMU_ARCH_ALL) 3308STEXI 3309@item --preconfig 3310@findex --preconfig 3311Pause QEMU for interactive configuration before the machine is created, 3312which allows querying and configuring properties that will affect 3313machine initialization. Use QMP command 'x-exit-preconfig' to exit 3314the preconfig state and move to the next state (i.e. run guest if -S 3315isn't used or pause the second time if -S is used). This option is 3316experimental. 3317ETEXI 3318 3319DEF("S", 0, QEMU_OPTION_S, \ 3320 "-S freeze CPU at startup (use 'c' to start execution)\n", 3321 QEMU_ARCH_ALL) 3322STEXI 3323@item -S 3324@findex -S 3325Do not start CPU at startup (you must type 'c' in the monitor). 3326ETEXI 3327 3328DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3329 "-realtime [mlock=on|off]\n" 3330 " run qemu with realtime features\n" 3331 " mlock=on|off controls mlock support (default: on)\n", 3332 QEMU_ARCH_ALL) 3333STEXI 3334@item -realtime mlock=on|off 3335@findex -realtime 3336Run qemu with realtime features. 3337mlocking qemu and guest memory can be enabled via @option{mlock=on} 3338(enabled by default). 3339ETEXI 3340 3341DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, 3342 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" 3343 " run qemu with overcommit hints\n" 3344 " mem-lock=on|off controls memory lock support (default: off)\n" 3345 " cpu-pm=on|off controls cpu power management (default: off)\n", 3346 QEMU_ARCH_ALL) 3347STEXI 3348@item -overcommit mem-lock=on|off 3349@item -overcommit cpu-pm=on|off 3350@findex -overcommit 3351Run qemu with hints about host resource overcommit. The default is 3352to assume that host overcommits all resources. 3353 3354Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled 3355by default). This works when host memory is not overcommitted and reduces the 3356worst-case latency for guest. This is equivalent to @option{realtime}. 3357 3358Guest ability to manage power state of host cpus (increasing latency for other 3359processes on the same host cpu, but decreasing latency for guest) can be 3360enabled via @option{cpu-pm=on} (disabled by default). This works best when 3361host CPU is not overcommitted. When used, host estimates of CPU cycle and power 3362utilization will be incorrect, not taking into account guest idle time. 3363ETEXI 3364 3365DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3366 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3367STEXI 3368@item -gdb @var{dev} 3369@findex -gdb 3370Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3371connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3372stdio are reasonable use case. The latter is allowing to start QEMU from 3373within gdb and establish the connection via a pipe: 3374@example 3375(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3376@end example 3377ETEXI 3378 3379DEF("s", 0, QEMU_OPTION_s, \ 3380 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3381 QEMU_ARCH_ALL) 3382STEXI 3383@item -s 3384@findex -s 3385Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3386(@pxref{gdb_usage}). 3387ETEXI 3388 3389DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3390 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3391 QEMU_ARCH_ALL) 3392STEXI 3393@item -d @var{item1}[,...] 3394@findex -d 3395Enable logging of specified items. Use '-d help' for a list of log items. 3396ETEXI 3397 3398DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3399 "-D logfile output log to logfile (default stderr)\n", 3400 QEMU_ARCH_ALL) 3401STEXI 3402@item -D @var{logfile} 3403@findex -D 3404Output log in @var{logfile} instead of to stderr 3405ETEXI 3406 3407DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3408 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3409 QEMU_ARCH_ALL) 3410STEXI 3411@item -dfilter @var{range1}[,...] 3412@findex -dfilter 3413Filter debug output to that relevant to a range of target addresses. The filter 3414spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3415@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3416addresses and sizes required. For example: 3417@example 3418 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3419@end example 3420Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3421the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3422block starting at 0xffffffc00005f000. 3423ETEXI 3424 3425DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3426 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3427 QEMU_ARCH_ALL) 3428STEXI 3429@item -L @var{path} 3430@findex -L 3431Set the directory for the BIOS, VGA BIOS and keymaps. 3432 3433To list all the data directories, use @code{-L help}. 3434ETEXI 3435 3436DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3437 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3438STEXI 3439@item -bios @var{file} 3440@findex -bios 3441Set the filename for the BIOS. 3442ETEXI 3443 3444DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3445 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3446STEXI 3447@item -enable-kvm 3448@findex -enable-kvm 3449Enable KVM full virtualization support. This option is only available 3450if KVM support is enabled when compiling. 3451ETEXI 3452 3453DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \ 3454 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386) 3455STEXI 3456@item -enable-hax 3457@findex -enable-hax 3458Enable HAX (Hardware-based Acceleration eXecution) support. This option 3459is only available if HAX support is enabled when compiling. HAX is only 3460applicable to MAC and Windows platform, and thus does not conflict with 3461KVM. This option is deprecated, use @option{-accel hax} instead. 3462ETEXI 3463 3464DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3465 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3466DEF("xen-create", 0, QEMU_OPTION_xen_create, 3467 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3468 " warning: should not be used when xend is in use\n", 3469 QEMU_ARCH_ALL) 3470DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3471 "-xen-attach attach to existing xen domain\n" 3472 " xend will use this when starting QEMU\n", 3473 QEMU_ARCH_ALL) 3474DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict, 3475 "-xen-domid-restrict restrict set of available xen operations\n" 3476 " to specified domain id. (Does not affect\n" 3477 " xenpv machine type).\n", 3478 QEMU_ARCH_ALL) 3479STEXI 3480@item -xen-domid @var{id} 3481@findex -xen-domid 3482Specify xen guest domain @var{id} (XEN only). 3483@item -xen-create 3484@findex -xen-create 3485Create domain using xen hypercalls, bypassing xend. 3486Warning: should not be used when xend is in use (XEN only). 3487@item -xen-attach 3488@findex -xen-attach 3489Attach to existing xen domain. 3490xend will use this when starting QEMU (XEN only). 3491@findex -xen-domid-restrict 3492Restrict set of available xen operations to specified domain id (XEN only). 3493ETEXI 3494 3495DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3496 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3497STEXI 3498@item -no-reboot 3499@findex -no-reboot 3500Exit instead of rebooting. 3501ETEXI 3502 3503DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3504 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3505STEXI 3506@item -no-shutdown 3507@findex -no-shutdown 3508Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3509This allows for instance switching to monitor to commit changes to the 3510disk image. 3511ETEXI 3512 3513DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3514 "-loadvm [tag|id]\n" \ 3515 " start right away with a saved state (loadvm in monitor)\n", 3516 QEMU_ARCH_ALL) 3517STEXI 3518@item -loadvm @var{file} 3519@findex -loadvm 3520Start right away with a saved state (@code{loadvm} in monitor) 3521ETEXI 3522 3523#ifndef _WIN32 3524DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3525 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3526#endif 3527STEXI 3528@item -daemonize 3529@findex -daemonize 3530Daemonize the QEMU process after initialization. QEMU will not detach from 3531standard IO until it is ready to receive connections on any of its devices. 3532This option is a useful way for external programs to launch QEMU without having 3533to cope with initialization race conditions. 3534ETEXI 3535 3536DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3537 "-option-rom rom load a file, rom, into the option ROM space\n", 3538 QEMU_ARCH_ALL) 3539STEXI 3540@item -option-rom @var{file} 3541@findex -option-rom 3542Load the contents of @var{file} as an option ROM. 3543This option is useful to load things like EtherBoot. 3544ETEXI 3545 3546HXCOMM Silently ignored for compatibility 3547DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3548 3549HXCOMM Options deprecated by -rtc 3550DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 3551DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3552 3553DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3554 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3555 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3556 QEMU_ARCH_ALL) 3557 3558STEXI 3559 3560@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3561@findex -rtc 3562Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3563UTC or local time, respectively. @code{localtime} is required for correct date in 3564MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3565format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3566 3567By default the RTC is driven by the host system time. This allows using of the 3568RTC as accurate reference clock inside the guest, specifically if the host 3569time is smoothly following an accurate external reference clock, e.g. via NTP. 3570If you want to isolate the guest time from the host, you can set @option{clock} 3571to @code{rt} instead. To even prevent it from progressing during suspension, 3572you can set it to @code{vm}. 3573 3574Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3575specifically with Windows' ACPI HAL. This option will try to figure out how 3576many timer interrupts were not processed by the Windows guest and will 3577re-inject them. 3578ETEXI 3579 3580DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3581 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3582 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3583 " instruction, enable aligning the host and virtual clocks\n" \ 3584 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3585STEXI 3586@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3587@findex -icount 3588Enable virtual instruction counter. The virtual cpu will execute one 3589instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3590then the virtual cpu speed will be automatically adjusted to keep virtual 3591time within a few seconds of real time. 3592 3593When the virtual cpu is sleeping, the virtual time will advance at default 3594speed unless @option{sleep=on|off} is specified. 3595With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3596instantly whenever the virtual cpu goes to sleep mode and will not advance 3597if no timer is enabled. This behavior give deterministic execution times from 3598the guest point of view. 3599 3600Note that while this option can give deterministic behavior, it does not 3601provide cycle accurate emulation. Modern CPUs contain superscalar out of 3602order cores with complex cache hierarchies. The number of instructions 3603executed often has little or no correlation with actual performance. 3604 3605@option{align=on} will activate the delay algorithm which will try 3606to synchronise the host clock and the virtual clock. The goal is to 3607have a guest running at the real frequency imposed by the shift option. 3608Whenever the guest clock is behind the host clock and if 3609@option{align=on} is specified then we print a message to the user 3610to inform about the delay. 3611Currently this option does not work when @option{shift} is @code{auto}. 3612Note: The sync algorithm will work for those shift values for which 3613the guest clock runs ahead of the host clock. Typically this happens 3614when the shift value is high (how high depends on the host machine). 3615 3616When @option{rr} option is specified deterministic record/replay is enabled. 3617Replay log is written into @var{filename} file in record mode and 3618read from this file in replay mode. 3619 3620Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3621at the start of execution recording. In replay mode this option is used 3622to load the initial VM state. 3623ETEXI 3624 3625DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3626 "-watchdog model\n" \ 3627 " enable virtual hardware watchdog [default=none]\n", 3628 QEMU_ARCH_ALL) 3629STEXI 3630@item -watchdog @var{model} 3631@findex -watchdog 3632Create a virtual hardware watchdog device. Once enabled (by a guest 3633action), the watchdog must be periodically polled by an agent inside 3634the guest or else the guest will be restarted. Choose a model for 3635which your guest has drivers. 3636 3637The @var{model} is the model of hardware watchdog to emulate. Use 3638@code{-watchdog help} to list available hardware models. Only one 3639watchdog can be enabled for a guest. 3640 3641The following models may be available: 3642@table @option 3643@item ib700 3644iBASE 700 is a very simple ISA watchdog with a single timer. 3645@item i6300esb 3646Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3647dual-timer watchdog. 3648@item diag288 3649A virtual watchdog for s390x backed by the diagnose 288 hypercall 3650(currently KVM only). 3651@end table 3652ETEXI 3653 3654DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3655 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \ 3656 " action when watchdog fires [default=reset]\n", 3657 QEMU_ARCH_ALL) 3658STEXI 3659@item -watchdog-action @var{action} 3660@findex -watchdog-action 3661 3662The @var{action} controls what QEMU will do when the watchdog timer 3663expires. 3664The default is 3665@code{reset} (forcefully reset the guest). 3666Other possible actions are: 3667@code{shutdown} (attempt to gracefully shutdown the guest), 3668@code{poweroff} (forcefully poweroff the guest), 3669@code{inject-nmi} (inject a NMI into the guest), 3670@code{pause} (pause the guest), 3671@code{debug} (print a debug message and continue), or 3672@code{none} (do nothing). 3673 3674Note that the @code{shutdown} action requires that the guest responds 3675to ACPI signals, which it may not be able to do in the sort of 3676situations where the watchdog would have expired, and thus 3677@code{-watchdog-action shutdown} is not recommended for production use. 3678 3679Examples: 3680 3681@table @code 3682@item -watchdog i6300esb -watchdog-action pause 3683@itemx -watchdog ib700 3684@end table 3685ETEXI 3686 3687DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3688 "-echr chr set terminal escape character instead of ctrl-a\n", 3689 QEMU_ARCH_ALL) 3690STEXI 3691 3692@item -echr @var{numeric_ascii_value} 3693@findex -echr 3694Change the escape character used for switching to the monitor when using 3695monitor and serial sharing. The default is @code{0x01} when using the 3696@code{-nographic} option. @code{0x01} is equal to pressing 3697@code{Control-a}. You can select a different character from the ascii 3698control keys where 1 through 26 map to Control-a through Control-z. For 3699instance you could use the either of the following to change the escape 3700character to Control-t. 3701@table @code 3702@item -echr 0x14 3703@itemx -echr 20 3704@end table 3705ETEXI 3706 3707DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3708 "-virtioconsole c\n" \ 3709 " set virtio console\n", QEMU_ARCH_ALL) 3710STEXI 3711@item -virtioconsole @var{c} 3712@findex -virtioconsole 3713Set virtio console. 3714This option is deprecated, please use @option{-device virtconsole} instead. 3715ETEXI 3716 3717DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3718 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3719STEXI 3720@item -show-cursor 3721@findex -show-cursor 3722Show cursor. 3723ETEXI 3724 3725DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3726 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3727STEXI 3728@item -tb-size @var{n} 3729@findex -tb-size 3730Set TB size. 3731ETEXI 3732 3733DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3734 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3735 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3736 "-incoming unix:socketpath\n" \ 3737 " prepare for incoming migration, listen on\n" \ 3738 " specified protocol and socket address\n" \ 3739 "-incoming fd:fd\n" \ 3740 "-incoming exec:cmdline\n" \ 3741 " accept incoming migration on given file descriptor\n" \ 3742 " or from given external command\n" \ 3743 "-incoming defer\n" \ 3744 " wait for the URI to be specified via migrate_incoming\n", 3745 QEMU_ARCH_ALL) 3746STEXI 3747@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3748@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3749@findex -incoming 3750Prepare for incoming migration, listen on a given tcp port. 3751 3752@item -incoming unix:@var{socketpath} 3753Prepare for incoming migration, listen on a given unix socket. 3754 3755@item -incoming fd:@var{fd} 3756Accept incoming migration from a given filedescriptor. 3757 3758@item -incoming exec:@var{cmdline} 3759Accept incoming migration as an output from specified external command. 3760 3761@item -incoming defer 3762Wait for the URI to be specified via migrate_incoming. The monitor can 3763be used to change settings (such as migration parameters) prior to issuing 3764the migrate_incoming to allow the migration to begin. 3765ETEXI 3766 3767DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3768 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3769STEXI 3770@item -only-migratable 3771@findex -only-migratable 3772Only allow migratable devices. Devices will not be allowed to enter an 3773unmigratable state. 3774ETEXI 3775 3776DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3777 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3778STEXI 3779@item -nodefaults 3780@findex -nodefaults 3781Don't create default devices. Normally, QEMU sets the default devices like serial 3782port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3783CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3784default devices. 3785ETEXI 3786 3787#ifndef _WIN32 3788DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3789 "-chroot dir chroot to dir just before starting the VM\n", 3790 QEMU_ARCH_ALL) 3791#endif 3792STEXI 3793@item -chroot @var{dir} 3794@findex -chroot 3795Immediately before starting guest execution, chroot to the specified 3796directory. Especially useful in combination with -runas. 3797ETEXI 3798 3799#ifndef _WIN32 3800DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3801 "-runas user change to user id user just before starting the VM\n" \ 3802 " user can be numeric uid:gid instead\n", 3803 QEMU_ARCH_ALL) 3804#endif 3805STEXI 3806@item -runas @var{user} 3807@findex -runas 3808Immediately before starting guest execution, drop root privileges, switching 3809to the specified user. 3810ETEXI 3811 3812DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3813 "-prom-env variable=value\n" 3814 " set OpenBIOS nvram variables\n", 3815 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3816STEXI 3817@item -prom-env @var{variable}=@var{value} 3818@findex -prom-env 3819Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3820ETEXI 3821DEF("semihosting", 0, QEMU_OPTION_semihosting, 3822 "-semihosting semihosting mode\n", 3823 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3824 QEMU_ARCH_MIPS) 3825STEXI 3826@item -semihosting 3827@findex -semihosting 3828Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3829ETEXI 3830DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3831 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3832 " semihosting configuration\n", 3833QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3834QEMU_ARCH_MIPS) 3835STEXI 3836@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3837@findex -semihosting-config 3838Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3839@table @option 3840@item target=@code{native|gdb|auto} 3841Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3842or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3843during debug sessions and @code{native} otherwise. 3844@item arg=@var{str1},arg=@var{str2},... 3845Allows the user to pass input arguments, and can be used multiple times to build 3846up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3847command line is still supported for backward compatibility. If both the 3848@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3849specified, the former is passed to semihosting as it always takes precedence. 3850@end table 3851ETEXI 3852DEF("old-param", 0, QEMU_OPTION_old_param, 3853 "-old-param old param mode\n", QEMU_ARCH_ARM) 3854STEXI 3855@item -old-param 3856@findex -old-param (ARM) 3857Old param mode (ARM only). 3858ETEXI 3859 3860DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3861 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \ 3862 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \ 3863 " Enable seccomp mode 2 system call filter (default 'off').\n" \ 3864 " use 'obsolete' to allow obsolete system calls that are provided\n" \ 3865 " by the kernel, but typically no longer used by modern\n" \ 3866 " C library implementations.\n" \ 3867 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \ 3868 " its privileges by blacklisting all set*uid|gid system calls.\n" \ 3869 " The value 'children' will deny set*uid|gid system calls for\n" \ 3870 " main QEMU process but will allow forks and execves to run unprivileged\n" \ 3871 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \ 3872 " blacklisting *fork and execve\n" \ 3873 " use 'resourcecontrol' to disable process affinity and schedular priority\n", 3874 QEMU_ARCH_ALL) 3875STEXI 3876@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}] 3877@findex -sandbox 3878Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3879disable it. The default is 'off'. 3880@table @option 3881@item obsolete=@var{string} 3882Enable Obsolete system calls 3883@item elevateprivileges=@var{string} 3884Disable set*uid|gid system calls 3885@item spawn=@var{string} 3886Disable *fork and execve 3887@item resourcecontrol=@var{string} 3888Disable process affinity and schedular priority 3889@end table 3890ETEXI 3891 3892DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3893 "-readconfig <file>\n", QEMU_ARCH_ALL) 3894STEXI 3895@item -readconfig @var{file} 3896@findex -readconfig 3897Read device configuration from @var{file}. This approach is useful when you want to spawn 3898QEMU process with many command line options but you don't want to exceed the command line 3899character limit. 3900ETEXI 3901DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3902 "-writeconfig <file>\n" 3903 " read/write config file\n", QEMU_ARCH_ALL) 3904STEXI 3905@item -writeconfig @var{file} 3906@findex -writeconfig 3907Write device configuration to @var{file}. The @var{file} can be either filename to save 3908command line and device configuration into file or dash @code{-}) character to print the 3909output to stdout. This can be later used as input file for @code{-readconfig} option. 3910ETEXI 3911HXCOMM Deprecated, same as -no-user-config 3912DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL) 3913DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3914 "-no-user-config\n" 3915 " do not load default user-provided config files at startup\n", 3916 QEMU_ARCH_ALL) 3917STEXI 3918@item -no-user-config 3919@findex -no-user-config 3920The @code{-no-user-config} option makes QEMU not load any of the user-provided 3921config files on @var{sysconfdir}. 3922ETEXI 3923DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3924 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3925 " specify tracing options\n", 3926 QEMU_ARCH_ALL) 3927STEXI 3928HXCOMM This line is not accurate, as some sub-options are backend-specific but 3929HXCOMM HX does not support conditional compilation of text. 3930@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 3931@findex -trace 3932@include qemu-option-trace.texi 3933ETEXI 3934 3935HXCOMM Internal use 3936DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3937DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3938 3939#ifdef __linux__ 3940DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3941 "-enable-fips enable FIPS 140-2 compliance\n", 3942 QEMU_ARCH_ALL) 3943#endif 3944STEXI 3945@item -enable-fips 3946@findex -enable-fips 3947Enable FIPS 140-2 compliance mode. 3948ETEXI 3949 3950HXCOMM Deprecated by -machine accel=tcg property 3951DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3952 3953DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3954 "-msg timestamp[=on|off]\n" 3955 " change the format of messages\n" 3956 " on|off controls leading timestamps (default:on)\n", 3957 QEMU_ARCH_ALL) 3958STEXI 3959@item -msg timestamp[=on|off] 3960@findex -msg 3961prepend a timestamp to each log message.(default:on) 3962ETEXI 3963 3964DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3965 "-dump-vmstate <file>\n" 3966 " Output vmstate information in JSON format to file.\n" 3967 " Use the scripts/vmstate-static-checker.py file to\n" 3968 " check for possible regressions in migration code\n" 3969 " by comparing two such vmstate dumps.\n", 3970 QEMU_ARCH_ALL) 3971STEXI 3972@item -dump-vmstate @var{file} 3973@findex -dump-vmstate 3974Dump json-encoded vmstate information for current machine type to file 3975in @var{file} 3976ETEXI 3977 3978STEXI 3979@end table 3980ETEXI 3981DEFHEADING() 3982 3983DEFHEADING(Generic object creation:) 3984STEXI 3985@table @option 3986ETEXI 3987 3988DEF("object", HAS_ARG, QEMU_OPTION_object, 3989 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3990 " create a new object of type TYPENAME setting properties\n" 3991 " in the order they are specified. Note that the 'id'\n" 3992 " property must be set. These objects are placed in the\n" 3993 " '/objects' path.\n", 3994 QEMU_ARCH_ALL) 3995STEXI 3996@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3997@findex -object 3998Create a new object of type @var{typename} setting properties 3999in the order they are specified. Note that the 'id' 4000property must be set. These objects are placed in the 4001'/objects' path. 4002 4003@table @option 4004 4005@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} 4006 4007Creates a memory file backend object, which can be used to back 4008the guest RAM with huge pages. 4009 4010The @option{id} parameter is a unique ID that will be used to reference this 4011memory region when configuring the @option{-numa} argument. 4012 4013The @option{size} option provides the size of the memory region, and accepts 4014common suffixes, eg @option{500M}. 4015 4016The @option{mem-path} provides the path to either a shared memory or huge page 4017filesystem mount. 4018 4019The @option{share} boolean option determines whether the memory 4020region is marked as private to QEMU, or shared. The latter allows 4021a co-operating external process to access the QEMU memory region. 4022 4023The @option{share} is also required for pvrdma devices due to 4024limitations in the RDMA API provided by Linux. 4025 4026Setting share=on might affect the ability to configure NUMA 4027bindings for the memory backend under some circumstances, see 4028Documentation/vm/numa_memory_policy.txt on the Linux kernel 4029source tree for additional details. 4030 4031Setting the @option{discard-data} boolean option to @var{on} 4032indicates that file contents can be destroyed when QEMU exits, 4033to avoid unnecessarily flushing data to the backing file. Note 4034that @option{discard-data} is only an optimization, and QEMU 4035might not discard file contents if it aborts unexpectedly or is 4036terminated using SIGKILL. 4037 4038The @option{merge} boolean option enables memory merge, also known as 4039MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for 4040memory deduplication. 4041 4042Setting the @option{dump} boolean option to @var{off} excludes the memory from 4043core dumps. This feature is also known as MADV_DONTDUMP. 4044 4045The @option{prealloc} boolean option enables memory preallocation. 4046 4047The @option{host-nodes} option binds the memory range to a list of NUMA host 4048nodes. 4049 4050The @option{policy} option sets the NUMA policy to one of the following values: 4051 4052@table @option 4053@item @var{default} 4054default host policy 4055 4056@item @var{preferred} 4057prefer the given host node list for allocation 4058 4059@item @var{bind} 4060restrict memory allocation to the given host node list 4061 4062@item @var{interleave} 4063interleave memory allocations across the given host node list 4064@end table 4065 4066The @option{align} option specifies the base address alignment when 4067QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg 4068@option{2M}. Some backend store specified by @option{mem-path} 4069requires an alignment different than the default one used by QEMU, eg 4070the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In 4071such cases, users can specify the required alignment via this option. 4072 4073@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} 4074 4075Creates a memory backend object, which can be used to back the guest RAM. 4076Memory backend objects offer more control than the @option{-m} option that is 4077traditionally used to define guest RAM. Please refer to 4078@option{memory-backend-file} for a description of the options. 4079 4080@item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size} 4081 4082Creates an anonymous memory file backend object, which allows QEMU to 4083share the memory with an external process (e.g. when using 4084vhost-user). The memory is allocated with memfd and optional 4085sealing. (Linux only) 4086 4087The @option{seal} option creates a sealed-file, that will block 4088further resizing the memory ('on' by default). 4089 4090The @option{hugetlb} option specify the file to be created resides in 4091the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with 4092the @option{hugetlb} option, the @option{hugetlbsize} option specify 4093the hugetlb page size on systems that support multiple hugetlb page 4094sizes (it must be a power of 2 value supported by the system). 4095 4096In some versions of Linux, the @option{hugetlb} option is incompatible 4097with the @option{seal} option (requires at least Linux 4.16). 4098 4099Please refer to @option{memory-backend-file} for a description of the 4100other options. 4101 4102@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4103 4104Creates a random number generator backend which obtains entropy from 4105a device on the host. The @option{id} parameter is a unique ID that 4106will be used to reference this entropy backend from the @option{virtio-rng} 4107device. The @option{filename} parameter specifies which file to obtain 4108entropy from and if omitted defaults to @option{/dev/random}. 4109 4110@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4111 4112Creates a random number generator backend which obtains entropy from 4113an external daemon running on the host. The @option{id} parameter is 4114a unique ID that will be used to reference this entropy backend from 4115the @option{virtio-rng} device. The @option{chardev} parameter is 4116the unique ID of a character device backend that provides the connection 4117to the RNG daemon. 4118 4119@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4120 4121Creates a TLS anonymous credentials object, which can be used to provide 4122TLS support on network backends. The @option{id} parameter is a unique 4123ID which network backends will use to access the credentials. The 4124@option{endpoint} is either @option{server} or @option{client} depending 4125on whether the QEMU network backend that uses the credentials will be 4126acting as a client or as a server. If @option{verify-peer} is enabled 4127(the default) then once the handshake is completed, the peer credentials 4128will be verified, though this is a no-op for anonymous credentials. 4129 4130The @var{dir} parameter tells QEMU where to find the credential 4131files. For server endpoints, this directory may contain a file 4132@var{dh-params.pem} providing diffie-hellman parameters to use 4133for the TLS server. If the file is missing, QEMU will generate 4134a set of DH parameters at startup. This is a computationally 4135expensive operation that consumes random pool entropy, so it is 4136recommended that a persistent set of parameters be generated 4137upfront and saved. 4138 4139@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] 4140 4141Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide 4142TLS support on network backends. The @option{id} parameter is a unique 4143ID which network backends will use to access the credentials. The 4144@option{endpoint} is either @option{server} or @option{client} depending 4145on whether the QEMU network backend that uses the credentials will be 4146acting as a client or as a server. For clients only, @option{username} 4147is the username which will be sent to the server. If omitted 4148it defaults to ``qemu''. 4149 4150The @var{dir} parameter tells QEMU where to find the keys file. 4151It is called ``@var{dir}/keys.psk'' and contains ``username:key'' 4152pairs. This file can most easily be created using the GnuTLS 4153@code{psktool} program. 4154 4155For server endpoints, @var{dir} may also contain a file 4156@var{dh-params.pem} providing diffie-hellman parameters to use 4157for the TLS server. If the file is missing, QEMU will generate 4158a set of DH parameters at startup. This is a computationally 4159expensive operation that consumes random pool entropy, so it is 4160recommended that a persistent set of parameters be generated 4161up front and saved. 4162 4163@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} 4164 4165Creates a TLS anonymous credentials object, which can be used to provide 4166TLS support on network backends. The @option{id} parameter is a unique 4167ID which network backends will use to access the credentials. The 4168@option{endpoint} is either @option{server} or @option{client} depending 4169on whether the QEMU network backend that uses the credentials will be 4170acting as a client or as a server. If @option{verify-peer} is enabled 4171(the default) then once the handshake is completed, the peer credentials 4172will be verified. With x509 certificates, this implies that the clients 4173must be provided with valid client certificates too. 4174 4175The @var{dir} parameter tells QEMU where to find the credential 4176files. For server endpoints, this directory may contain a file 4177@var{dh-params.pem} providing diffie-hellman parameters to use 4178for the TLS server. If the file is missing, QEMU will generate 4179a set of DH parameters at startup. This is a computationally 4180expensive operation that consumes random pool entropy, so it is 4181recommended that a persistent set of parameters be generated 4182upfront and saved. 4183 4184For x509 certificate credentials the directory will contain further files 4185providing the x509 certificates. The certificates must be stored 4186in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4187@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4188@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4189 4190For the @var{server-key.pem} and @var{client-key.pem} files which 4191contain sensitive private keys, it is possible to use an encrypted 4192version by providing the @var{passwordid} parameter. This provides 4193the ID of a previously created @code{secret} object containing the 4194password for decryption. 4195 4196The @var{priority} parameter allows to override the global default 4197priority used by gnutls. This can be useful if the system administrator 4198needs to use a weaker set of crypto priorities for QEMU without 4199potentially forcing the weakness onto all applications. Or conversely 4200if one wants wants a stronger default for QEMU than for all other 4201applications, they can do this through this parameter. Its format is 4202a gnutls priority string as described at 4203@url{https://gnutls.org/manual/html_node/Priority-Strings.html}. 4204 4205@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4206 4207Interval @var{t} can't be 0, this filter batches the packet delivery: all 4208packets arriving in a given interval on netdev @var{netdevid} are delayed 4209until the end of the interval. Interval is in microseconds. 4210@option{status} is optional that indicate whether the netfilter is 4211on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4212 4213queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4214 4215@option{all}: the filter is attached both to the receive and the transmit 4216 queue of the netdev (default). 4217 4218@option{rx}: the filter is attached to the receive queue of the netdev, 4219 where it will receive packets sent to the netdev. 4220 4221@option{tx}: the filter is attached to the transmit queue of the netdev, 4222 where it will receive packets sent by the netdev. 4223 4224@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4225 4226filter-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. 4227 4228@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4229 4230filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4231@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag, 4232filter-redirector will redirect packet with vnet_hdr_len. 4233Create a filter-redirector we need to differ outdev id from indev id, id can not 4234be the same. we can just use indev or outdev, but at least one of indev or outdev 4235need to be specified. 4236 4237@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support] 4238 4239Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4240secondary from primary to keep secondary tcp connection,and rewrite 4241tcp packet to primary from secondary make tcp packet can be handled by 4242client.if it has the vnet_hdr_support flag, we can parse packet with vnet header. 4243 4244usage: 4245colo secondary: 4246-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4247-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4248-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4249 4250@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4251 4252Dump the network traffic on netdev @var{dev} to the file specified by 4253@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4254The file format is libpcap, so it can be analyzed with tools such as tcpdump 4255or Wireshark. 4256 4257@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support] 4258 4259Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4260secondary packet. If the packets are same, we will output primary 4261packet to outdev@var{chardevid}, else we will notify colo-frame 4262do checkpoint and send primary packet to outdev@var{chardevid}. 4263if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len. 4264 4265we must use it with the help of filter-mirror and filter-redirector. 4266 4267@example 4268 4269primary: 4270-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4271-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4272-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4273-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4274-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4275-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4276-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4277-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4278-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4279-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4280-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4281-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4282 4283secondary: 4284-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4285-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4286-chardev socket,id=red0,host=3.3.3.3,port=9003 4287-chardev socket,id=red1,host=3.3.3.3,port=9004 4288-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4289-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4290 4291@end example 4292 4293If you want to know the detail of above command line, you can read 4294the colo-compare git log. 4295 4296@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4297 4298Creates a cryptodev backend which executes crypto opreation from 4299the QEMU cipher APIS. The @var{id} parameter is 4300a unique ID that will be used to reference this cryptodev backend from 4301the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4302which specify the queue number of cryptodev backend, the default of 4303@var{queues} is 1. 4304 4305@example 4306 4307 # qemu-system-x86_64 \ 4308 [...] \ 4309 -object cryptodev-backend-builtin,id=cryptodev0 \ 4310 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4311 [...] 4312@end example 4313 4314@item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}] 4315 4316Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}. 4317The @var{id} parameter is a unique ID that will be used to reference this 4318cryptodev backend from the @option{virtio-crypto} device. 4319The chardev should be a unix domain socket backed one. The vhost-user uses 4320a specifically defined protocol to pass vhost ioctl replacement messages 4321to an application on the other end of the socket. 4322The @var{queues} parameter is optional, which specify the queue number 4323of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1. 4324 4325@example 4326 4327 # qemu-system-x86_64 \ 4328 [...] \ 4329 -chardev socket,id=chardev0,path=/path/to/socket \ 4330 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \ 4331 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4332 [...] 4333@end example 4334 4335@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4336@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4337 4338Defines a secret to store a password, encryption key, or some other sensitive 4339data. The sensitive data can either be passed directly via the @var{data} 4340parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4341parameter is insecure unless the sensitive data is encrypted. 4342 4343The sensitive data can be provided in raw format (the default), or base64. 4344When encoded as JSON, the raw format only supports valid UTF-8 characters, 4345so base64 is recommended for sending binary data. QEMU will convert from 4346which ever format is provided to the format it needs internally. eg, an 4347RBD password can be provided in raw format, even though it will be base64 4348encoded when passed onto the RBD sever. 4349 4350For added protection, it is possible to encrypt the data associated with 4351a secret using the AES-256-CBC cipher. Use of encryption is indicated 4352by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4353parameter provides the ID of a previously defined secret that contains 4354the AES-256 decryption key. This key should be 32-bytes long and be 4355base64 encoded. The @var{iv} parameter provides the random initialization 4356vector used for encryption of this particular secret and should be a 4357base64 encrypted string of the 16-byte IV. 4358 4359The simplest (insecure) usage is to provide the secret inline 4360 4361@example 4362 4363 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4364 4365@end example 4366 4367The simplest secure usage is to provide the secret via a file 4368 4369 # printf "letmein" > mypasswd.txt 4370 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4371 4372For greater security, AES-256-CBC should be used. To illustrate usage, 4373consider the openssl command line tool which can encrypt the data. Note 4374that when encrypting, the plaintext must be padded to the cipher block 4375size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4376 4377First a master key needs to be created in base64 encoding: 4378 4379@example 4380 # openssl rand -base64 32 > key.b64 4381 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4382@end example 4383 4384Each secret to be encrypted needs to have a random initialization vector 4385generated. These do not need to be kept secret 4386 4387@example 4388 # openssl rand -base64 16 > iv.b64 4389 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4390@end example 4391 4392The secret to be defined can now be encrypted, in this case we're 4393telling openssl to base64 encode the result, but it could be left 4394as raw bytes if desired. 4395 4396@example 4397 # SECRET=$(printf "letmein" | 4398 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4399@end example 4400 4401When launching QEMU, create a master secret pointing to @code{key.b64} 4402and specify that to be used to decrypt the user password. Pass the 4403contents of @code{iv.b64} to the second secret 4404 4405@example 4406 # $QEMU \ 4407 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4408 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4409 data=$SECRET,iv=$(<iv.b64) 4410@end example 4411 4412@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}] 4413 4414Create a Secure Encrypted Virtualization (SEV) guest object, which can be used 4415to provide the guest memory encryption support on AMD processors. 4416 4417When memory encryption is enabled, one of the physical address bit (aka the 4418C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos} 4419is used to provide the C-bit position. The C-bit position is Host family dependent 4420hence user must provide this value. On EPYC, the value should be 47. 4421 4422When memory encryption is enabled, we loose certain bits in physical address space. 4423The @option{reduced-phys-bits} is used to provide the number of bits we loose in 4424physical address space. Similar to C-bit, the value is Host family dependent. 4425On EPYC, the value should be 5. 4426 4427The @option{sev-device} provides the device file to use for communicating with 4428the SEV firmware running inside AMD Secure Processor. The default device is 4429'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are 4430created by CCP driver. 4431 4432The @option{policy} provides the guest policy to be enforced by the SEV firmware 4433and restrict what configuration and operational commands can be performed on this 4434guest by the hypervisor. The policy should be provided by the guest owner and is 4435bound to the guest and cannot be changed throughout the lifetime of the guest. 4436The default is 0. 4437 4438If guest @option{policy} allows sharing the key with another SEV guest then 4439@option{handle} can be use to provide handle of the guest from which to share 4440the key. 4441 4442The @option{dh-cert-file} and @option{session-file} provides the guest owner's 4443Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters 4444are used for establishing a cryptographic session with the guest owner to 4445negotiate keys used for attestation. The file must be encoded in base64. 4446 4447e.g to launch a SEV guest 4448@example 4449 # $QEMU \ 4450 ...... 4451 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ 4452 -machine ...,memory-encryption=sev0 4453 ..... 4454 4455@end example 4456@end table 4457 4458ETEXI 4459 4460 4461HXCOMM This is the last statement. Insert new options before this line! 4462STEXI 4463@end table 4464ETEXI 4465
