1HXCOMM Use DEFHEADING() to define headings in both help text and texi 2HXCOMM Text between STEXI and ETEXI are copied to texi version and 3HXCOMM discarded from C version 4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to 5HXCOMM construct option structures, enums and help message for specified 6HXCOMM architectures. 7HXCOMM HXCOMM can be used for comments, discarded from both texi and C 8 9DEFHEADING(Standard options:) 10STEXI 11@table @option 12ETEXI 13 14DEF("help", 0, QEMU_OPTION_h, 15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL) 16STEXI 17@item -h 18@findex -h 19Display help and exit 20ETEXI 21 22DEF("version", 0, QEMU_OPTION_version, 23 "-version display version information and exit\n", QEMU_ARCH_ALL) 24STEXI 25@item -version 26@findex -version 27Display version information and exit 28ETEXI 29 30DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ 31 "-machine [type=]name[,prop[=value][,...]]\n" 32 " selects emulated machine ('-machine help' for list)\n" 33 " property accel=accel1[:accel2[:...]] selects accelerator\n" 34 " supported accelerators are kvm, xen, hax, hvf, whpx or tcg (default: tcg)\n" 35 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n" 36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n" 37 " kvm_shadow_mem=size of KVM shadow MMU in bytes\n" 38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 39 " mem-merge=on|off controls memory merge support (default: on)\n" 40 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n" 41 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" 42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" 43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" 44 " nvdimm=on|off controls NVDIMM support (default=off)\n" 45 " enforce-config-section=on|off enforce configuration section migration (default=off)\n" 46 " memory-encryption=@var{} memory encryption object to use (default=none)\n", 47 QEMU_ARCH_ALL) 48STEXI 49@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 50@findex -machine 51Select the emulated machine by @var{name}. Use @code{-machine help} to list 52available machines. 53 54For architectures which aim to support live migration compatibility 55across releases, each release will introduce a new versioned machine 56type. For example, the 2.8.0 release introduced machine types 57``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures. 58 59To allow live migration of guests from QEMU version 2.8.0, to QEMU 60version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8'' 61and ``pc-q35-2.8'' machines too. To allow users live migrating VMs 62to skip multiple intermediate releases when upgrading, new releases 63of QEMU will support machine types from many previous versions. 64 65Supported machine properties are: 66@table @option 67@item accel=@var{accels1}[:@var{accels2}[:...]] 68This is used to enable an accelerator. Depending on the target architecture, 69kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 70more than one accelerator specified, the next one is used if the previous one 71fails to initialize. 72@item kernel_irqchip=on|off 73Controls in-kernel irqchip support for the chosen accelerator when available. 74@item gfx_passthru=on|off 75Enables IGD GFX passthrough support for the chosen machine when available. 76@item vmport=on|off|auto 77Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 78value based on accel. For accel=xen the default is off otherwise the default 79is on. 80@item kvm_shadow_mem=size 81Defines the size of the KVM shadow MMU. 82@item dump-guest-core=on|off 83Include guest memory in a core dump. The default is on. 84@item mem-merge=on|off 85Enables or disables memory merge support. This feature, when supported by 86the host, de-duplicates identical memory pages among VMs instances 87(enabled by default). 88@item aes-key-wrap=on|off 89Enables or disables AES key wrapping support on s390-ccw hosts. This feature 90controls whether AES wrapping keys will be created to allow 91execution of AES cryptographic functions. The default is on. 92@item dea-key-wrap=on|off 93Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 94controls whether DEA wrapping keys will be created to allow 95execution of DEA cryptographic functions. The default is on. 96@item nvdimm=on|off 97Enables or disables NVDIMM support. The default is off. 98@item enforce-config-section=on|off 99If @option{enforce-config-section} is set to @var{on}, force migration 100code to send configuration section even if the machine-type sets the 101@option{migration.send-configuration} property to @var{off}. 102NOTE: this parameter is deprecated. Please use @option{-global} 103@option{migration.send-configuration}=@var{on|off} instead. 104@item memory-encryption=@var{} 105Memory encryption object to use. The default is none. 106@end table 107ETEXI 108 109HXCOMM Deprecated by -machine 110DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 111 112DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 113 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 114STEXI 115@item -cpu @var{model} 116@findex -cpu 117Select CPU model (@code{-cpu help} for list and additional feature selection) 118ETEXI 119 120DEF("accel", HAS_ARG, QEMU_OPTION_accel, 121 "-accel [accel=]accelerator[,thread=single|multi]\n" 122 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n" 123 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL) 124STEXI 125@item -accel @var{name}[,prop=@var{value}[,...]] 126@findex -accel 127This is used to enable an accelerator. Depending on the target architecture, 128kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 129more than one accelerator specified, the next one is used if the previous one 130fails to initialize. 131@table @option 132@item thread=single|multi 133Controls number of TCG threads. When the TCG is multi-threaded there will be one 134thread per vCPU therefor taking advantage of additional host cores. The default 135is to enable multi-threading where both the back-end and front-ends support it and 136no incompatible TCG features have been enabled (e.g. icount/replay). 137@end table 138ETEXI 139 140DEF("smp", HAS_ARG, QEMU_OPTION_smp, 141 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 142 " set the number of CPUs to 'n' [default=1]\n" 143 " maxcpus= maximum number of total cpus, including\n" 144 " offline CPUs for hotplug, etc\n" 145 " cores= number of CPU cores on one socket\n" 146 " threads= number of threads on one CPU core\n" 147 " sockets= number of discrete sockets in the system\n", 148 QEMU_ARCH_ALL) 149STEXI 150@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 151@findex -smp 152Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 153CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 154to 4. 155For the PC target, the number of @var{cores} per socket, the number 156of @var{threads} per cores and the total number of @var{sockets} can be 157specified. Missing values will be computed. If any on the three values is 158given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 159specifies the maximum number of hotpluggable CPUs. 160ETEXI 161 162DEF("numa", HAS_ARG, QEMU_OPTION_numa, 163 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 164 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 165 "-numa dist,src=source,dst=destination,val=distance\n" 166 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n", 167 QEMU_ARCH_ALL) 168STEXI 169@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 170@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 171@itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance} 172@itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}] 173@findex -numa 174Define a NUMA node and assign RAM and VCPUs to it. 175Set the NUMA distance from a source node to a destination node. 176 177Legacy VCPU assignment uses @samp{cpus} option where 178@var{firstcpu} and @var{lastcpu} are CPU indexes. Each 179@samp{cpus} option represent a contiguous range of CPU indexes 180(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous 181set of VCPUs can be represented by providing multiple @samp{cpus} 182options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically 183split between them. 184 185For example, the following option assigns VCPUs 0, 1, 2 and 5 to 186a NUMA node: 187@example 188-numa node,cpus=0-2,cpus=5 189@end example 190 191@samp{cpu} option is a new alternative to @samp{cpus} option 192which uses @samp{socket-id|core-id|thread-id} properties to assign 193CPU objects to a @var{node} using topology layout properties of CPU. 194The set of properties is machine specific, and depends on used 195machine type/@samp{smp} options. It could be queried with 196@samp{hotpluggable-cpus} monitor command. 197@samp{node-id} property specifies @var{node} to which CPU object 198will be assigned, it's required for @var{node} to be declared 199with @samp{node} option before it's used with @samp{cpu} option. 200 201For example: 202@example 203-M pc \ 204-smp 1,sockets=2,maxcpus=2 \ 205-numa node,nodeid=0 -numa node,nodeid=1 \ 206-numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1 207@end example 208 209@samp{mem} assigns a given RAM amount to a node. @samp{memdev} 210assigns RAM from a given memory backend device to a node. If 211@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is 212split equally between them. 213 214@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, 215if one node uses @samp{memdev}, all of them have to use it. 216 217@var{source} and @var{destination} are NUMA node IDs. 218@var{distance} is the NUMA distance from @var{source} to @var{destination}. 219The distance from a node to itself is always 10. If any pair of nodes is 220given a distance, then all pairs must be given distances. Although, when 221distances are only given in one direction for each pair of nodes, then 222the distances in the opposite directions are assumed to be the same. If, 223however, an asymmetrical pair of distances is given for even one node 224pair, then all node pairs must be provided distance values for both 225directions, even when they are symmetrical. When a node is unreachable 226from another node, set the pair's distance to 255. 227 228Note that the -@option{numa} option doesn't allocate any of the 229specified resources, it just assigns existing resources to NUMA 230nodes. This means that one still has to use the @option{-m}, 231@option{-smp} options to allocate RAM and VCPUs respectively. 232 233ETEXI 234 235DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 236 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 237 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 238STEXI 239@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 240@findex -add-fd 241 242Add a file descriptor to an fd set. Valid options are: 243 244@table @option 245@item fd=@var{fd} 246This option defines the file descriptor of which a duplicate is added to fd set. 247The file descriptor cannot be stdin, stdout, or stderr. 248@item set=@var{set} 249This option defines the ID of the fd set to add the file descriptor to. 250@item opaque=@var{opaque} 251This option defines a free-form string that can be used to describe @var{fd}. 252@end table 253 254You can open an image using pre-opened file descriptors from an fd set: 255@example 256qemu-system-i386 257-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 258-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 259-drive file=/dev/fdset/2,index=0,media=disk 260@end example 261ETEXI 262 263DEF("set", HAS_ARG, QEMU_OPTION_set, 264 "-set group.id.arg=value\n" 265 " set <arg> parameter for item <id> of type <group>\n" 266 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 267STEXI 268@item -set @var{group}.@var{id}.@var{arg}=@var{value} 269@findex -set 270Set parameter @var{arg} for item @var{id} of type @var{group} 271ETEXI 272 273DEF("global", HAS_ARG, QEMU_OPTION_global, 274 "-global driver.property=value\n" 275 "-global driver=driver,property=property,value=value\n" 276 " set a global default for a driver property\n", 277 QEMU_ARCH_ALL) 278STEXI 279@item -global @var{driver}.@var{prop}=@var{value} 280@itemx -global driver=@var{driver},property=@var{property},value=@var{value} 281@findex -global 282Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 283 284@example 285qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img 286@end example 287 288In particular, you can use this to set driver properties for devices which are 289created automatically by the machine model. To create a device which is not 290created automatically and set properties on it, use -@option{device}. 291 292-global @var{driver}.@var{prop}=@var{value} is shorthand for -global 293driver=@var{driver},property=@var{prop},value=@var{value}. The 294longhand syntax works even when @var{driver} contains a dot. 295ETEXI 296 297DEF("boot", HAS_ARG, QEMU_OPTION_boot, 298 "-boot [order=drives][,once=drives][,menu=on|off]\n" 299 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 300 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 301 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 302 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 303 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 304 QEMU_ARCH_ALL) 305STEXI 306@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] 307@findex -boot 308Specify boot order @var{drives} as a string of drive letters. Valid 309drive letters depend on the target architecture. The x86 PC uses: a, b 310(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 311from network adapter 1-4), hard disk boot is the default. To apply a 312particular boot order only on the first startup, specify it via 313@option{once}. Note that the @option{order} or @option{once} parameter 314should not be used together with the @option{bootindex} property of 315devices, since the firmware implementations normally do not support both 316at the same time. 317 318Interactive boot menus/prompts can be enabled via @option{menu=on} as far 319as firmware/BIOS supports them. The default is non-interactive boot. 320 321A splash picture could be passed to bios, enabling user to show it as logo, 322when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 323supports them. Currently Seabios for X86 system support it. 324limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 325format(true color). The resolution should be supported by the SVGA mode, so 326the recommended is 320x240, 640x480, 800x640. 327 328A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 329when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 330reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 331system support it. 332 333Do strict boot via @option{strict=on} as far as firmware/BIOS 334supports it. This only effects when boot priority is changed by 335bootindex options. The default is non-strict boot. 336 337@example 338# try to boot from network first, then from hard disk 339qemu-system-i386 -boot order=nc 340# boot from CD-ROM first, switch back to default order after reboot 341qemu-system-i386 -boot once=d 342# boot with a splash picture for 5 seconds. 343qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 344@end example 345 346Note: The legacy format '-boot @var{drives}' is still supported but its 347use is discouraged as it may be removed from future versions. 348ETEXI 349 350DEF("m", HAS_ARG, QEMU_OPTION_m, 351 "-m [size=]megs[,slots=n,maxmem=size]\n" 352 " configure guest RAM\n" 353 " size: initial amount of guest memory\n" 354 " slots: number of hotplug slots (default: none)\n" 355 " maxmem: maximum amount of guest memory (default: none)\n" 356 "NOTE: Some architectures might enforce a specific granularity\n", 357 QEMU_ARCH_ALL) 358STEXI 359@item -m [size=]@var{megs}[,slots=n,maxmem=size] 360@findex -m 361Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 362Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 363megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 364could be used to set amount of hotpluggable memory slots and maximum amount of 365memory. Note that @var{maxmem} must be aligned to the page size. 366 367For example, the following command-line sets the guest startup RAM size to 3681GB, creates 3 slots to hotplug additional memory and sets the maximum 369memory the guest can reach to 4GB: 370 371@example 372qemu-system-x86_64 -m 1G,slots=3,maxmem=4G 373@end example 374 375If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 376be enabled and the guest startup RAM will never increase. 377ETEXI 378 379DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 380 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 381STEXI 382@item -mem-path @var{path} 383@findex -mem-path 384Allocate guest RAM from a temporarily created file in @var{path}. 385ETEXI 386 387DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 388 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 389 QEMU_ARCH_ALL) 390STEXI 391@item -mem-prealloc 392@findex -mem-prealloc 393Preallocate memory when using -mem-path. 394ETEXI 395 396DEF("k", HAS_ARG, QEMU_OPTION_k, 397 "-k language use keyboard layout (for example 'fr' for French)\n", 398 QEMU_ARCH_ALL) 399STEXI 400@item -k @var{language} 401@findex -k 402Use keyboard layout @var{language} (for example @code{fr} for 403French). This option is only needed where it is not easy to get raw PC 404keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses 405display). You don't normally need to use it on PC/Linux or PC/Windows 406hosts. 407 408The available layouts are: 409@example 410ar de-ch es fo fr-ca hu ja mk no pt-br sv 411da en-gb et fr fr-ch is lt nl pl ru th 412de en-us fi fr-be hr it lv nl-be pt sl tr 413@end example 414 415The default is @code{en-us}. 416ETEXI 417 418 419DEF("audio-help", 0, QEMU_OPTION_audio_help, 420 "-audio-help print list of audio drivers and their options\n", 421 QEMU_ARCH_ALL) 422STEXI 423@item -audio-help 424@findex -audio-help 425Will show the audio subsystem help: list of drivers, tunable 426parameters. 427ETEXI 428 429DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 430 "-soundhw c1,... enable audio support\n" 431 " and only specified sound cards (comma separated list)\n" 432 " use '-soundhw help' to get the list of supported cards\n" 433 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 434STEXI 435@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 436@findex -soundhw 437Enable audio and selected sound hardware. Use 'help' to print all 438available sound hardware. 439 440@example 441qemu-system-i386 -soundhw sb16,adlib disk.img 442qemu-system-i386 -soundhw es1370 disk.img 443qemu-system-i386 -soundhw ac97 disk.img 444qemu-system-i386 -soundhw hda disk.img 445qemu-system-i386 -soundhw all disk.img 446qemu-system-i386 -soundhw help 447@end example 448 449Note that Linux's i810_audio OSS kernel (for AC97) module might 450require manually specifying clocking. 451 452@example 453modprobe i810_audio clocking=48000 454@end example 455ETEXI 456 457DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 458 "-balloon virtio[,addr=str]\n" 459 " enable virtio balloon device (deprecated)\n", QEMU_ARCH_ALL) 460STEXI 461@item -balloon virtio[,addr=@var{addr}] 462@findex -balloon 463Enable virtio balloon device, optionally with PCI address @var{addr}. This 464option is deprecated, use @option{-device virtio-balloon} instead. 465ETEXI 466 467DEF("device", HAS_ARG, QEMU_OPTION_device, 468 "-device driver[,prop[=value][,...]]\n" 469 " add device (based on driver)\n" 470 " prop=value,... sets driver properties\n" 471 " use '-device help' to print all possible drivers\n" 472 " use '-device driver,help' to print all possible properties\n", 473 QEMU_ARCH_ALL) 474STEXI 475@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 476@findex -device 477Add device @var{driver}. @var{prop}=@var{value} sets driver 478properties. Valid properties depend on the driver. To get help on 479possible drivers and properties, use @code{-device help} and 480@code{-device @var{driver},help}. 481 482Some drivers are: 483@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}] 484 485Add an IPMI BMC. This is a simulation of a hardware management 486interface processor that normally sits on a system. It provides 487a watchdog and the ability to reset and power control the system. 488You need to connect this to an IPMI interface to make it useful 489 490The IPMI slave address to use for the BMC. The default is 0x20. 491This address is the BMC's address on the I2C network of management 492controllers. If you don't know what this means, it is safe to ignore 493it. 494 495@table @option 496@item bmc=@var{id} 497The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 498@item slave_addr=@var{val} 499Define slave address to use for the BMC. The default is 0x20. 500@item sdrfile=@var{file} 501file containing raw Sensor Data Records (SDR) data. The default is none. 502@item fruareasize=@var{val} 503size of a Field Replaceable Unit (FRU) area. The default is 1024. 504@item frudatafile=@var{file} 505file containing raw Field Replaceable Unit (FRU) inventory data. The default is none. 506@end table 507 508@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 509 510Add a connection to an external IPMI BMC simulator. Instead of 511locally emulating the BMC like the above item, instead connect 512to an external entity that provides the IPMI services. 513 514A connection is made to an external BMC simulator. If you do this, it 515is strongly recommended that you use the "reconnect=" chardev option 516to reconnect to the simulator if the connection is lost. Note that if 517this is not used carefully, it can be a security issue, as the 518interface has the ability to send resets, NMIs, and power off the VM. 519It's best if QEMU makes a connection to an external simulator running 520on a secure port on localhost, so neither the simulator nor QEMU is 521exposed to any outside network. 522 523See the "lanserv/README.vm" file in the OpenIPMI library for more 524details on the external interface. 525 526@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 527 528Add a KCS IPMI interafce on the ISA bus. This also adds a 529corresponding ACPI and SMBIOS entries, if appropriate. 530 531@table @option 532@item bmc=@var{id} 533The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 534@item ioport=@var{val} 535Define the I/O address of the interface. The default is 0xca0 for KCS. 536@item irq=@var{val} 537Define the interrupt to use. The default is 5. To disable interrupts, 538set this to 0. 539@end table 540 541@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 542 543Like the KCS interface, but defines a BT interface. The default port is 5440xe4 and the default interrupt is 5. 545 546ETEXI 547 548DEF("name", HAS_ARG, QEMU_OPTION_name, 549 "-name string1[,process=string2][,debug-threads=on|off]\n" 550 " set the name of the guest\n" 551 " string1 sets the window title and string2 the process name (on Linux)\n" 552 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 553 " NOTE: The thread names are for debugging and not a stable API.\n", 554 QEMU_ARCH_ALL) 555STEXI 556@item -name @var{name} 557@findex -name 558Sets the @var{name} of the guest. 559This name will be displayed in the SDL window caption. 560The @var{name} will also be used for the VNC server. 561Also optionally set the top visible process name in Linux. 562Naming of individual threads can also be enabled on Linux to aid debugging. 563ETEXI 564 565DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 566 "-uuid %08x-%04x-%04x-%04x-%012x\n" 567 " specify machine UUID\n", QEMU_ARCH_ALL) 568STEXI 569@item -uuid @var{uuid} 570@findex -uuid 571Set system UUID. 572ETEXI 573 574STEXI 575@end table 576ETEXI 577DEFHEADING() 578 579DEFHEADING(Block device options:) 580STEXI 581@table @option 582ETEXI 583 584DEF("fda", HAS_ARG, QEMU_OPTION_fda, 585 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 586DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 587STEXI 588@item -fda @var{file} 589@itemx -fdb @var{file} 590@findex -fda 591@findex -fdb 592Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 593ETEXI 594 595DEF("hda", HAS_ARG, QEMU_OPTION_hda, 596 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 597DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 598DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 599 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 600DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 601STEXI 602@item -hda @var{file} 603@itemx -hdb @var{file} 604@itemx -hdc @var{file} 605@itemx -hdd @var{file} 606@findex -hda 607@findex -hdb 608@findex -hdc 609@findex -hdd 610Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 611ETEXI 612 613DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 614 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 615 QEMU_ARCH_ALL) 616STEXI 617@item -cdrom @var{file} 618@findex -cdrom 619Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 620@option{-cdrom} at the same time). You can use the host CD-ROM by 621using @file{/dev/cdrom} as filename (@pxref{host_drives}). 622ETEXI 623 624DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev, 625 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n" 626 " [,cache.direct=on|off][,cache.no-flush=on|off]\n" 627 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n" 628 " [,driver specific parameters...]\n" 629 " configure a block backend\n", QEMU_ARCH_ALL) 630STEXI 631@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]] 632@findex -blockdev 633 634Define a new block driver node. Some of the options apply to all block drivers, 635other options are only accepted for a specific block driver. See below for a 636list of generic options and options for the most common block drivers. 637 638Options that expect a reference to another node (e.g. @code{file}) can be 639given in two ways. Either you specify the node name of an already existing node 640(file=@var{node-name}), or you define a new node inline, adding options 641for the referenced node after a dot (file.filename=@var{path},file.aio=native). 642 643A block driver node created with @option{-blockdev} can be used for a guest 644device by specifying its node name for the @code{drive} property in a 645@option{-device} argument that defines a block device. 646 647@table @option 648@item Valid options for any block driver node: 649 650@table @code 651@item driver 652Specifies the block driver to use for the given node. 653@item node-name 654This defines the name of the block driver node by which it will be referenced 655later. The name must be unique, i.e. it must not match the name of a different 656block driver node, or (if you use @option{-drive} as well) the ID of a drive. 657 658If no node name is specified, it is automatically generated. The generated node 659name is not intended to be predictable and changes between QEMU invocations. 660For the top level, an explicit node name must be specified. 661@item read-only 662Open the node read-only. Guest write attempts will fail. 663@item cache.direct 664The host page cache can be avoided with @option{cache.direct=on}. This will 665attempt to do disk IO directly to the guest's memory. QEMU may still perform an 666internal copy of the data. 667@item cache.no-flush 668In case you don't care about data integrity over host failures, you can use 669@option{cache.no-flush=on}. This option tells QEMU that it never needs to write 670any data to the disk but can instead keep things in cache. If anything goes 671wrong, like your host losing power, the disk storage getting disconnected 672accidentally, etc. your image will most probably be rendered unusable. 673@item discard=@var{discard} 674@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls 675whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are 676ignored or passed to the filesystem. Some machine types may not support 677discard requests. 678@item detect-zeroes=@var{detect-zeroes} 679@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 680conversion of plain zero writes by the OS to driver specific optimized 681zero write commands. You may even choose "unmap" if @var{discard} is set 682to "unmap" to allow a zero write to be converted to an @code{unmap} operation. 683@end table 684 685@item Driver-specific options for @code{file} 686 687This is the protocol-level block driver for accessing regular files. 688 689@table @code 690@item filename 691The path to the image file in the local filesystem 692@item aio 693Specifies the AIO backend (threads/native, default: threads) 694@item locking 695Specifies whether the image file is protected with Linux OFD / POSIX locks. The 696default is to use the Linux Open File Descriptor API if available, otherwise no 697lock is applied. (auto/on/off, default: auto) 698@end table 699Example: 700@example 701-blockdev driver=file,node-name=disk,filename=disk.img 702@end example 703 704@item Driver-specific options for @code{raw} 705 706This is the image format block driver for raw images. It is usually 707stacked on top of a protocol level block driver such as @code{file}. 708 709@table @code 710@item file 711Reference to or definition of the data source block driver node 712(e.g. a @code{file} driver node) 713@end table 714Example 1: 715@example 716-blockdev driver=file,node-name=disk_file,filename=disk.img 717-blockdev driver=raw,node-name=disk,file=disk_file 718@end example 719Example 2: 720@example 721-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img 722@end example 723 724@item Driver-specific options for @code{qcow2} 725 726This is the image format block driver for qcow2 images. It is usually 727stacked on top of a protocol level block driver such as @code{file}. 728 729@table @code 730@item file 731Reference to or definition of the data source block driver node 732(e.g. a @code{file} driver node) 733 734@item backing 735Reference to or definition of the backing file block device (default is taken 736from the image file). It is allowed to pass @code{null} here in order to disable 737the default backing file. 738 739@item lazy-refcounts 740Whether to enable the lazy refcounts feature (on/off; default is taken from the 741image file) 742 743@item cache-size 744The maximum total size of the L2 table and refcount block caches in bytes 745(default: 1048576 bytes or 8 clusters, whichever is larger) 746 747@item l2-cache-size 748The maximum size of the L2 table cache in bytes 749(default: 4/5 of the total cache size) 750 751@item refcount-cache-size 752The maximum size of the refcount block cache in bytes 753(default: 1/5 of the total cache size) 754 755@item cache-clean-interval 756Clean unused entries in the L2 and refcount caches. The interval is in seconds. 757The default value is 0 and it disables this feature. 758 759@item pass-discard-request 760Whether discard requests to the qcow2 device should be forwarded to the data 761source (on/off; default: on if discard=unmap is specified, off otherwise) 762 763@item pass-discard-snapshot 764Whether discard requests for the data source should be issued when a snapshot 765operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off; 766default: on) 767 768@item pass-discard-other 769Whether discard requests for the data source should be issued on other 770occasions where a cluster gets freed (on/off; default: off) 771 772@item overlap-check 773Which overlap checks to perform for writes to the image 774(none/constant/cached/all; default: cached). For details or finer 775granularity control refer to the QAPI documentation of @code{blockdev-add}. 776@end table 777 778Example 1: 779@example 780-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2 781-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216 782@end example 783Example 2: 784@example 785-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2 786@end example 787 788@item Driver-specific options for other drivers 789Please refer to the QAPI documentation of the @code{blockdev-add} QMP command. 790 791@end table 792 793ETEXI 794 795DEF("drive", HAS_ARG, QEMU_OPTION_drive, 796 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 797 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 798 " [,snapshot=on|off][,rerror=ignore|stop|report]\n" 799 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 800 " [,readonly=on|off][,copy-on-read=on|off]\n" 801 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 802 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 803 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 804 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 805 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 806 " [[,iops_size=is]]\n" 807 " [[,group=g]]\n" 808 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 809STEXI 810@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 811@findex -drive 812 813Define a new drive. This includes creating a block driver node (the backend) as 814well as a guest device, and is mostly a shortcut for defining the corresponding 815@option{-blockdev} and @option{-device} options. 816 817@option{-drive} accepts all options that are accepted by @option{-blockdev}. In 818addition, it knows the following options: 819 820@table @option 821@item file=@var{file} 822This option defines which disk image (@pxref{disk_images}) to use with 823this drive. If the filename contains comma, you must double it 824(for instance, "file=my,,file" to use file "my,file"). 825 826Special files such as iSCSI devices can be specified using protocol 827specific URLs. See the section for "Device URL Syntax" for more information. 828@item if=@var{interface} 829This option defines on which type on interface the drive is connected. 830Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none. 831@item bus=@var{bus},unit=@var{unit} 832These options define where is connected the drive by defining the bus number and 833the unit id. 834@item index=@var{index} 835This option defines where is connected the drive by using an index in the list 836of available connectors of a given interface type. 837@item media=@var{media} 838This option defines the type of the media: disk or cdrom. 839@item snapshot=@var{snapshot} 840@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 841(see @option{-snapshot}). 842@item cache=@var{cache} 843@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" 844and controls how the host cache is used to access block data. This is a 845shortcut that sets the @option{cache.direct} and @option{cache.no-flush} 846options (as in @option{-blockdev}), and additionally @option{cache.writeback}, 847which provides a default for the @option{write-cache} option of block guest 848devices (as in @option{-device}). The modes correspond to the following 849settings: 850 851@c Our texi2pod.pl script doesn't support @multitable, so fall back to using 852@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage 853@c and the HTML output. 854@example 855@ │ cache.writeback cache.direct cache.no-flush 856─────────────┼───────────────────────────────────────────────── 857writeback │ on off off 858none │ on on off 859writethrough │ off off off 860directsync │ off on off 861unsafe │ on off on 862@end example 863 864The default mode is @option{cache=writeback}. 865 866@item aio=@var{aio} 867@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 868@item format=@var{format} 869Specify which disk @var{format} will be used rather than detecting 870the format. Can be used to specify format=raw to avoid interpreting 871an untrusted format header. 872@item werror=@var{action},rerror=@var{action} 873Specify which @var{action} to take on write and read errors. Valid actions are: 874"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 875"report" (report the error to the guest), "enospc" (pause QEMU only if the 876host disk is full; report the error to the guest otherwise). 877The default setting is @option{werror=enospc} and @option{rerror=report}. 878@item copy-on-read=@var{copy-on-read} 879@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 880file sectors into the image file. 881@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w} 882Specify bandwidth throttling limits in bytes per second, either for all request 883types or for reads or writes only. Small values can lead to timeouts or hangs 884inside the guest. A safe minimum for disks is 2 MB/s. 885@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm} 886Specify bursts in bytes per second, either for all request types or for reads 887or writes only. Bursts allow the guest I/O to spike above the limit 888temporarily. 889@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w} 890Specify request rate limits in requests per second, either for all request 891types or for reads or writes only. 892@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm} 893Specify bursts in requests per second, either for all request types or for reads 894or writes only. Bursts allow the guest I/O to spike above the limit 895temporarily. 896@item iops_size=@var{is} 897Let every @var{is} bytes of a request count as a new request for iops 898throttling purposes. Use this option to prevent guests from circumventing iops 899limits by sending fewer but larger requests. 900@item group=@var{g} 901Join a throttling quota group with given name @var{g}. All drives that are 902members of the same group are accounted for together. Use this option to 903prevent guests from circumventing throttling limits by using many small disks 904instead of a single larger disk. 905@end table 906 907By default, the @option{cache.writeback=on} mode is used. It will report data 908writes as completed as soon as the data is present in the host page cache. 909This is safe as long as your guest OS makes sure to correctly flush disk caches 910where needed. If your guest OS does not handle volatile disk write caches 911correctly and your host crashes or loses power, then the guest may experience 912data corruption. 913 914For such guests, you should consider using @option{cache.writeback=off}. This 915means that the host page cache will be used to read and write data, but write 916notification will be sent to the guest only after QEMU has made sure to flush 917each write to the disk. Be aware that this has a major impact on performance. 918 919When using the @option{-snapshot} option, unsafe caching is always used. 920 921Copy-on-read avoids accessing the same backing file sectors repeatedly and is 922useful when the backing file is over a slow network. By default copy-on-read 923is off. 924 925Instead of @option{-cdrom} you can use: 926@example 927qemu-system-i386 -drive file=file,index=2,media=cdrom 928@end example 929 930Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 931use: 932@example 933qemu-system-i386 -drive file=file,index=0,media=disk 934qemu-system-i386 -drive file=file,index=1,media=disk 935qemu-system-i386 -drive file=file,index=2,media=disk 936qemu-system-i386 -drive file=file,index=3,media=disk 937@end example 938 939You can open an image using pre-opened file descriptors from an fd set: 940@example 941qemu-system-i386 942-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 943-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 944-drive file=/dev/fdset/2,index=0,media=disk 945@end example 946 947You can connect a CDROM to the slave of ide0: 948@example 949qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 950@end example 951 952If you don't specify the "file=" argument, you define an empty drive: 953@example 954qemu-system-i386 -drive if=ide,index=1,media=cdrom 955@end example 956 957Instead of @option{-fda}, @option{-fdb}, you can use: 958@example 959qemu-system-i386 -drive file=file,index=0,if=floppy 960qemu-system-i386 -drive file=file,index=1,if=floppy 961@end example 962 963By default, @var{interface} is "ide" and @var{index} is automatically 964incremented: 965@example 966qemu-system-i386 -drive file=a -drive file=b" 967@end example 968is interpreted like: 969@example 970qemu-system-i386 -hda a -hdb b 971@end example 972ETEXI 973 974DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 975 "-mtdblock file use 'file' as on-board Flash memory image\n", 976 QEMU_ARCH_ALL) 977STEXI 978@item -mtdblock @var{file} 979@findex -mtdblock 980Use @var{file} as on-board Flash memory image. 981ETEXI 982 983DEF("sd", HAS_ARG, QEMU_OPTION_sd, 984 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 985STEXI 986@item -sd @var{file} 987@findex -sd 988Use @var{file} as SecureDigital card image. 989ETEXI 990 991DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 992 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 993STEXI 994@item -pflash @var{file} 995@findex -pflash 996Use @var{file} as a parallel flash image. 997ETEXI 998 999DEF("snapshot", 0, QEMU_OPTION_snapshot, 1000 "-snapshot write to temporary files instead of disk image files\n", 1001 QEMU_ARCH_ALL) 1002STEXI 1003@item -snapshot 1004@findex -snapshot 1005Write to temporary files instead of disk image files. In this case, 1006the raw disk image you use is not written back. You can however force 1007the write back by pressing @key{C-a s} (@pxref{disk_images}). 1008ETEXI 1009 1010DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 1011 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 1012 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n" 1013 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n" 1014 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n" 1015 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n" 1016 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n" 1017 " [[,throttling.iops-size=is]]\n", 1018 QEMU_ARCH_ALL) 1019 1020STEXI 1021 1022@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}] 1023@findex -fsdev 1024Define a new file system device. Valid options are: 1025@table @option 1026@item @var{fsdriver} 1027This option specifies the fs driver backend to use. 1028Currently "local", "handle" and "proxy" file system drivers are supported. 1029@item id=@var{id} 1030Specifies identifier for this device 1031@item path=@var{path} 1032Specifies the export path for the file system device. Files under 1033this path will be available to the 9p client on the guest. 1034@item security_model=@var{security_model} 1035Specifies the security model to be used for this export path. 1036Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1037In "passthrough" security model, files are stored using the same 1038credentials as they are created on the guest. This requires QEMU 1039to run as root. In "mapped-xattr" security model, some of the file 1040attributes like uid, gid, mode bits and link target are stored as 1041file attributes. For "mapped-file" these attributes are stored in the 1042hidden .virtfs_metadata directory. Directories exported by this security model cannot 1043interact with other unix tools. "none" security model is same as 1044passthrough except the sever won't report failures if it fails to 1045set file attributes like ownership. Security model is mandatory 1046only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 1047security model as a parameter. 1048@item writeout=@var{writeout} 1049This is an optional argument. The only supported value is "immediate". 1050This means that host page cache will be used to read and write data but 1051write notification will be sent to the guest only when the data has been 1052reported as written by the storage subsystem. 1053@item readonly 1054Enables exporting 9p share as a readonly mount for guests. By default 1055read-write access is given. 1056@item socket=@var{socket} 1057Enables proxy filesystem driver to use passed socket file for communicating 1058with virtfs-proxy-helper 1059@item sock_fd=@var{sock_fd} 1060Enables proxy filesystem driver to use passed socket descriptor for 1061communicating with virtfs-proxy-helper. Usually a helper like libvirt 1062will create socketpair and pass one of the fds as sock_fd 1063@item fmode=@var{fmode} 1064Specifies the default mode for newly created files on the host. Works only 1065with security models "mapped-xattr" and "mapped-file". 1066@item dmode=@var{dmode} 1067Specifies the default mode for newly created directories on the host. Works 1068only with security models "mapped-xattr" and "mapped-file". 1069@end table 1070 1071-fsdev option is used along with -device driver "virtio-9p-pci". 1072@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 1073Options for virtio-9p-pci driver are: 1074@table @option 1075@item fsdev=@var{id} 1076Specifies the id value specified along with -fsdev option 1077@item mount_tag=@var{mount_tag} 1078Specifies the tag name to be used by the guest to mount this export point 1079@end table 1080 1081ETEXI 1082 1083DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 1084 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 1085 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n", 1086 QEMU_ARCH_ALL) 1087 1088STEXI 1089 1090@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}] 1091@findex -virtfs 1092 1093The general form of a Virtual File system pass-through options are: 1094@table @option 1095@item @var{fsdriver} 1096This option specifies the fs driver backend to use. 1097Currently "local", "handle" and "proxy" file system drivers are supported. 1098@item id=@var{id} 1099Specifies identifier for this device 1100@item path=@var{path} 1101Specifies the export path for the file system device. Files under 1102this path will be available to the 9p client on the guest. 1103@item security_model=@var{security_model} 1104Specifies the security model to be used for this export path. 1105Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1106In "passthrough" security model, files are stored using the same 1107credentials as they are created on the guest. This requires QEMU 1108to run as root. In "mapped-xattr" security model, some of the file 1109attributes like uid, gid, mode bits and link target are stored as 1110file attributes. For "mapped-file" these attributes are stored in the 1111hidden .virtfs_metadata directory. Directories exported by this security model cannot 1112interact with other unix tools. "none" security model is same as 1113passthrough except the sever won't report failures if it fails to 1114set file attributes like ownership. Security model is mandatory only 1115for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 1116model as a parameter. 1117@item writeout=@var{writeout} 1118This is an optional argument. The only supported value is "immediate". 1119This means that host page cache will be used to read and write data but 1120write notification will be sent to the guest only when the data has been 1121reported as written by the storage subsystem. 1122@item readonly 1123Enables exporting 9p share as a readonly mount for guests. By default 1124read-write access is given. 1125@item socket=@var{socket} 1126Enables proxy filesystem driver to use passed socket file for 1127communicating with virtfs-proxy-helper. Usually a helper like libvirt 1128will create socketpair and pass one of the fds as sock_fd 1129@item sock_fd 1130Enables proxy filesystem driver to use passed 'sock_fd' as the socket 1131descriptor for interfacing with virtfs-proxy-helper 1132@item fmode=@var{fmode} 1133Specifies the default mode for newly created files on the host. Works only 1134with security models "mapped-xattr" and "mapped-file". 1135@item dmode=@var{dmode} 1136Specifies the default mode for newly created directories on the host. Works 1137only with security models "mapped-xattr" and "mapped-file". 1138@end table 1139ETEXI 1140 1141DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 1142 "-virtfs_synth Create synthetic file system image\n", 1143 QEMU_ARCH_ALL) 1144STEXI 1145@item -virtfs_synth 1146@findex -virtfs_synth 1147Create synthetic file system image 1148ETEXI 1149 1150DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 1151 "-iscsi [user=user][,password=password]\n" 1152 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 1153 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 1154 " [,timeout=timeout]\n" 1155 " iSCSI session parameters\n", QEMU_ARCH_ALL) 1156 1157STEXI 1158@item -iscsi 1159@findex -iscsi 1160Configure iSCSI session parameters. 1161ETEXI 1162 1163STEXI 1164@end table 1165ETEXI 1166DEFHEADING() 1167 1168DEFHEADING(USB options:) 1169STEXI 1170@table @option 1171ETEXI 1172 1173DEF("usb", 0, QEMU_OPTION_usb, 1174 "-usb enable the USB driver (if it is not used by default yet)\n", 1175 QEMU_ARCH_ALL) 1176STEXI 1177@item -usb 1178@findex -usb 1179Enable the USB driver (if it is not used by default yet). 1180ETEXI 1181 1182DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 1183 "-usbdevice name add the host or guest USB device 'name'\n", 1184 QEMU_ARCH_ALL) 1185STEXI 1186 1187@item -usbdevice @var{devname} 1188@findex -usbdevice 1189Add the USB device @var{devname}. Note that this option is deprecated, 1190please use @code{-device usb-...} instead. @xref{usb_devices}. 1191 1192@table @option 1193 1194@item mouse 1195Virtual Mouse. This will override the PS/2 mouse emulation when activated. 1196 1197@item tablet 1198Pointer device that uses absolute coordinates (like a touchscreen). This 1199means QEMU is able to report the mouse position without having to grab the 1200mouse. Also overrides the PS/2 mouse emulation when activated. 1201 1202@item braille 1203Braille device. This will use BrlAPI to display the braille output on a real 1204or fake device. 1205 1206@end table 1207ETEXI 1208 1209STEXI 1210@end table 1211ETEXI 1212DEFHEADING() 1213 1214DEFHEADING(Display options:) 1215STEXI 1216@table @option 1217ETEXI 1218 1219DEF("display", HAS_ARG, QEMU_OPTION_display, 1220 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 1221 " [,window_close=on|off][,gl=on|core|es|off]\n" 1222 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 1223 "-display vnc=<display>[,<optargs>]\n" 1224 "-display curses\n" 1225 "-display none" 1226 " select display type\n" 1227 "The default display is equivalent to\n" 1228#if defined(CONFIG_GTK) 1229 "\t\"-display gtk\"\n" 1230#elif defined(CONFIG_SDL) 1231 "\t\"-display sdl\"\n" 1232#elif defined(CONFIG_COCOA) 1233 "\t\"-display cocoa\"\n" 1234#elif defined(CONFIG_VNC) 1235 "\t\"-vnc localhost:0,to=99,id=default\"\n" 1236#else 1237 "\t\"-display none\"\n" 1238#endif 1239 , QEMU_ARCH_ALL) 1240STEXI 1241@item -display @var{type} 1242@findex -display 1243Select type of display to use. This option is a replacement for the 1244old style -sdl/-curses/... options. Valid values for @var{type} are 1245@table @option 1246@item sdl 1247Display video output via SDL (usually in a separate graphics 1248window; see the SDL documentation for other possibilities). 1249@item curses 1250Display video output via curses. For graphics device models which 1251support a text mode, QEMU can display this output using a 1252curses/ncurses interface. Nothing is displayed when the graphics 1253device is in graphical mode or if the graphics device does not support 1254a text mode. Generally only the VGA device models support text mode. 1255@item none 1256Do not display video output. The guest will still see an emulated 1257graphics card, but its output will not be displayed to the QEMU 1258user. This option differs from the -nographic option in that it 1259only affects what is done with video output; -nographic also changes 1260the destination of the serial and parallel port data. 1261@item gtk 1262Display video output in a GTK window. This interface provides drop-down 1263menus and other UI elements to configure and control the VM during 1264runtime. 1265@item vnc 1266Start a VNC server on display <arg> 1267@end table 1268ETEXI 1269 1270DEF("nographic", 0, QEMU_OPTION_nographic, 1271 "-nographic disable graphical output and redirect serial I/Os to console\n", 1272 QEMU_ARCH_ALL) 1273STEXI 1274@item -nographic 1275@findex -nographic 1276Normally, if QEMU is compiled with graphical window support, it displays 1277output such as guest graphics, guest console, and the QEMU monitor in a 1278window. With this option, you can totally disable graphical output so 1279that QEMU is a simple command line application. The emulated serial port 1280is redirected on the console and muxed with the monitor (unless 1281redirected elsewhere explicitly). Therefore, you can still use QEMU to 1282debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1283switching between the console and monitor. 1284ETEXI 1285 1286DEF("curses", 0, QEMU_OPTION_curses, 1287 "-curses shorthand for -display curses\n", 1288 QEMU_ARCH_ALL) 1289STEXI 1290@item -curses 1291@findex -curses 1292Normally, if QEMU is compiled with graphical window support, it displays 1293output such as guest graphics, guest console, and the QEMU monitor in a 1294window. With this option, QEMU can display the VGA output when in text 1295mode using a curses/ncurses interface. Nothing is displayed in graphical 1296mode. 1297ETEXI 1298 1299DEF("no-frame", 0, QEMU_OPTION_no_frame, 1300 "-no-frame open SDL window without a frame and window decorations\n", 1301 QEMU_ARCH_ALL) 1302STEXI 1303@item -no-frame 1304@findex -no-frame 1305Do not use decorations for SDL windows and start them using the whole 1306available screen space. This makes the using QEMU in a dedicated desktop 1307workspace more convenient. 1308ETEXI 1309 1310DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1311 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1312 QEMU_ARCH_ALL) 1313STEXI 1314@item -alt-grab 1315@findex -alt-grab 1316Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1317affects the special keys (for fullscreen, monitor-mode switching, etc). 1318ETEXI 1319 1320DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1321 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1322 QEMU_ARCH_ALL) 1323STEXI 1324@item -ctrl-grab 1325@findex -ctrl-grab 1326Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1327affects the special keys (for fullscreen, monitor-mode switching, etc). 1328ETEXI 1329 1330DEF("no-quit", 0, QEMU_OPTION_no_quit, 1331 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1332STEXI 1333@item -no-quit 1334@findex -no-quit 1335Disable SDL window close capability. 1336ETEXI 1337 1338DEF("sdl", 0, QEMU_OPTION_sdl, 1339 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1340STEXI 1341@item -sdl 1342@findex -sdl 1343Enable SDL. 1344ETEXI 1345 1346DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1347 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1348 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1349 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1350 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1351 " [,tls-ciphers=<list>]\n" 1352 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1353 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1354 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1355 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1356 " [,jpeg-wan-compression=[auto|never|always]]\n" 1357 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1358 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1359 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1360 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1361 " [,gl=[on|off]][,rendernode=<file>]\n" 1362 " enable spice\n" 1363 " at least one of {port, tls-port} is mandatory\n", 1364 QEMU_ARCH_ALL) 1365STEXI 1366@item -spice @var{option}[,@var{option}[,...]] 1367@findex -spice 1368Enable the spice remote desktop protocol. Valid options are 1369 1370@table @option 1371 1372@item port=<nr> 1373Set the TCP port spice is listening on for plaintext channels. 1374 1375@item addr=<addr> 1376Set the IP address spice is listening on. Default is any address. 1377 1378@item ipv4 1379@itemx ipv6 1380@itemx unix 1381Force using the specified IP version. 1382 1383@item password=<secret> 1384Set the password you need to authenticate. 1385 1386@item sasl 1387Require that the client use SASL to authenticate with the spice. 1388The exact choice of authentication method used is controlled from the 1389system / user's SASL configuration file for the 'qemu' service. This 1390is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1391unprivileged user, an environment variable SASL_CONF_PATH can be used 1392to make it search alternate locations for the service config. 1393While some SASL auth methods can also provide data encryption (eg GSSAPI), 1394it is recommended that SASL always be combined with the 'tls' and 1395'x509' settings to enable use of SSL and server certificates. This 1396ensures a data encryption preventing compromise of authentication 1397credentials. 1398 1399@item disable-ticketing 1400Allow client connects without authentication. 1401 1402@item disable-copy-paste 1403Disable copy paste between the client and the guest. 1404 1405@item disable-agent-file-xfer 1406Disable spice-vdagent based file-xfer between the client and the guest. 1407 1408@item tls-port=<nr> 1409Set the TCP port spice is listening on for encrypted channels. 1410 1411@item x509-dir=<dir> 1412Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1413 1414@item x509-key-file=<file> 1415@itemx x509-key-password=<file> 1416@itemx x509-cert-file=<file> 1417@itemx x509-cacert-file=<file> 1418@itemx x509-dh-key-file=<file> 1419The x509 file names can also be configured individually. 1420 1421@item tls-ciphers=<list> 1422Specify which ciphers to use. 1423 1424@item tls-channel=[main|display|cursor|inputs|record|playback] 1425@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1426Force specific channel to be used with or without TLS encryption. The 1427options can be specified multiple times to configure multiple 1428channels. The special name "default" can be used to set the default 1429mode. For channels which are not explicitly forced into one mode the 1430spice client is allowed to pick tls/plaintext as he pleases. 1431 1432@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1433Configure image compression (lossless). 1434Default is auto_glz. 1435 1436@item jpeg-wan-compression=[auto|never|always] 1437@itemx zlib-glz-wan-compression=[auto|never|always] 1438Configure wan image compression (lossy for slow links). 1439Default is auto. 1440 1441@item streaming-video=[off|all|filter] 1442Configure video stream detection. Default is off. 1443 1444@item agent-mouse=[on|off] 1445Enable/disable passing mouse events via vdagent. Default is on. 1446 1447@item playback-compression=[on|off] 1448Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1449 1450@item seamless-migration=[on|off] 1451Enable/disable spice seamless migration. Default is off. 1452 1453@item gl=[on|off] 1454Enable/disable OpenGL context. Default is off. 1455 1456@item rendernode=<file> 1457DRM render node for OpenGL rendering. If not specified, it will pick 1458the first available. (Since 2.9) 1459 1460@end table 1461ETEXI 1462 1463DEF("portrait", 0, QEMU_OPTION_portrait, 1464 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1465 QEMU_ARCH_ALL) 1466STEXI 1467@item -portrait 1468@findex -portrait 1469Rotate graphical output 90 deg left (only PXA LCD). 1470ETEXI 1471 1472DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1473 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1474 QEMU_ARCH_ALL) 1475STEXI 1476@item -rotate @var{deg} 1477@findex -rotate 1478Rotate graphical output some deg left (only PXA LCD). 1479ETEXI 1480 1481DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1482 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1483 " select video card type\n", QEMU_ARCH_ALL) 1484STEXI 1485@item -vga @var{type} 1486@findex -vga 1487Select type of VGA card to emulate. Valid values for @var{type} are 1488@table @option 1489@item cirrus 1490Cirrus Logic GD5446 Video card. All Windows versions starting from 1491Windows 95 should recognize and use this graphic card. For optimal 1492performances, use 16 bit color depth in the guest and the host OS. 1493(This card was the default before QEMU 2.2) 1494@item std 1495Standard VGA card with Bochs VBE extensions. If your guest OS 1496supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1497to use high resolution modes (>= 1280x1024x16) then you should use 1498this option. (This card is the default since QEMU 2.2) 1499@item vmware 1500VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1501recent XFree86/XOrg server or Windows guest with a driver for this 1502card. 1503@item qxl 1504QXL paravirtual graphic card. It is VGA compatible (including VESA 15052.0 VBE support). Works best with qxl guest drivers installed though. 1506Recommended choice when using the spice protocol. 1507@item tcx 1508(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1509sun4m machines and offers both 8-bit and 24-bit colour depths at a 1510fixed resolution of 1024x768. 1511@item cg3 1512(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1513for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1514resolutions aimed at people wishing to run older Solaris versions. 1515@item virtio 1516Virtio VGA card. 1517@item none 1518Disable VGA card. 1519@end table 1520ETEXI 1521 1522DEF("full-screen", 0, QEMU_OPTION_full_screen, 1523 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1524STEXI 1525@item -full-screen 1526@findex -full-screen 1527Start in full screen. 1528ETEXI 1529 1530DEF("g", 1, QEMU_OPTION_g , 1531 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1532 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1533STEXI 1534@item -g @var{width}x@var{height}[x@var{depth}] 1535@findex -g 1536Set the initial graphical resolution and depth (PPC, SPARC only). 1537ETEXI 1538 1539DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1540 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1541STEXI 1542@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1543@findex -vnc 1544Normally, if QEMU is compiled with graphical window support, it displays 1545output such as guest graphics, guest console, and the QEMU monitor in a 1546window. With this option, you can have QEMU listen on VNC display 1547@var{display} and redirect the VGA display over the VNC session. It is 1548very useful to enable the usb tablet device when using this option 1549(option @option{-device usb-tablet}). When using the VNC display, you 1550must use the @option{-k} parameter to set the keyboard layout if you are 1551not using en-us. Valid syntax for the @var{display} is 1552 1553@table @option 1554 1555@item to=@var{L} 1556 1557With this option, QEMU will try next available VNC @var{display}s, until the 1558number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1559available, e.g. port 5900+@var{display} is already used by another 1560application. By default, to=0. 1561 1562@item @var{host}:@var{d} 1563 1564TCP connections will only be allowed from @var{host} on display @var{d}. 1565By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1566be omitted in which case the server will accept connections from any host. 1567 1568@item unix:@var{path} 1569 1570Connections will be allowed over UNIX domain sockets where @var{path} is the 1571location of a unix socket to listen for connections on. 1572 1573@item none 1574 1575VNC is initialized but not started. The monitor @code{change} command 1576can be used to later start the VNC server. 1577 1578@end table 1579 1580Following the @var{display} value there may be one or more @var{option} flags 1581separated by commas. Valid options are 1582 1583@table @option 1584 1585@item reverse 1586 1587Connect to a listening VNC client via a ``reverse'' connection. The 1588client is specified by the @var{display}. For reverse network 1589connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1590is a TCP port number, not a display number. 1591 1592@item websocket 1593 1594Opens an additional TCP listening port dedicated to VNC Websocket connections. 1595If a bare @var{websocket} option is given, the Websocket port is 15965700+@var{display}. An alternative port can be specified with the 1597syntax @code{websocket}=@var{port}. 1598 1599If @var{host} is specified connections will only be allowed from this host. 1600It is possible to control the websocket listen address independently, using 1601the syntax @code{websocket}=@var{host}:@var{port}. 1602 1603If no TLS credentials are provided, the websocket connection runs in 1604unencrypted mode. If TLS credentials are provided, the websocket connection 1605requires encrypted client connections. 1606 1607@item password 1608 1609Require that password based authentication is used for client connections. 1610 1611The password must be set separately using the @code{set_password} command in 1612the @ref{pcsys_monitor}. The syntax to change your password is: 1613@code{set_password <protocol> <password>} where <protocol> could be either 1614"vnc" or "spice". 1615 1616If you would like to change <protocol> password expiration, you should use 1617@code{expire_password <protocol> <expiration-time>} where expiration time could 1618be one of the following options: now, never, +seconds or UNIX time of 1619expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1620to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1621date and time). 1622 1623You can also use keywords "now" or "never" for the expiration time to 1624allow <protocol> password to expire immediately or never expire. 1625 1626@item tls-creds=@var{ID} 1627 1628Provides the ID of a set of TLS credentials to use to secure the 1629VNC server. They will apply to both the normal VNC server socket 1630and the websocket socket (if enabled). Setting TLS credentials 1631will cause the VNC server socket to enable the VeNCrypt auth 1632mechanism. The credentials should have been previously created 1633using the @option{-object tls-creds} argument. 1634 1635@item sasl 1636 1637Require that the client use SASL to authenticate with the VNC server. 1638The exact choice of authentication method used is controlled from the 1639system / user's SASL configuration file for the 'qemu' service. This 1640is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1641unprivileged user, an environment variable SASL_CONF_PATH can be used 1642to make it search alternate locations for the service config. 1643While some SASL auth methods can also provide data encryption (eg GSSAPI), 1644it is recommended that SASL always be combined with the 'tls' and 1645'x509' settings to enable use of SSL and server certificates. This 1646ensures a data encryption preventing compromise of authentication 1647credentials. See the @ref{vnc_security} section for details on using 1648SASL authentication. 1649 1650@item acl 1651 1652Turn on access control lists for checking of the x509 client certificate 1653and SASL party. For x509 certs, the ACL check is made against the 1654certificate's distinguished name. This is something that looks like 1655@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1656made against the username, which depending on the SASL plugin, may 1657include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1658When the @option{acl} flag is set, the initial access list will be 1659empty, with a @code{deny} policy. Thus no one will be allowed to 1660use the VNC server until the ACLs have been loaded. This can be 1661achieved using the @code{acl} monitor command. 1662 1663@item lossy 1664 1665Enable lossy compression methods (gradient, JPEG, ...). If this 1666option is set, VNC client may receive lossy framebuffer updates 1667depending on its encoding settings. Enabling this option can save 1668a lot of bandwidth at the expense of quality. 1669 1670@item non-adaptive 1671 1672Disable adaptive encodings. Adaptive encodings are enabled by default. 1673An adaptive encoding will try to detect frequently updated screen regions, 1674and send updates in these regions using a lossy encoding (like JPEG). 1675This can be really helpful to save bandwidth when playing videos. Disabling 1676adaptive encodings restores the original static behavior of encodings 1677like Tight. 1678 1679@item share=[allow-exclusive|force-shared|ignore] 1680 1681Set display sharing policy. 'allow-exclusive' allows clients to ask 1682for exclusive access. As suggested by the rfb spec this is 1683implemented by dropping other connections. Connecting multiple 1684clients in parallel requires all clients asking for a shared session 1685(vncviewer: -shared switch). This is the default. 'force-shared' 1686disables exclusive client access. Useful for shared desktop sessions, 1687where you don't want someone forgetting specify -shared disconnect 1688everybody else. 'ignore' completely ignores the shared flag and 1689allows everybody connect unconditionally. Doesn't conform to the rfb 1690spec but is traditional QEMU behavior. 1691 1692@item key-delay-ms 1693 1694Set keyboard delay, for key down and key up events, in milliseconds. 1695Default is 10. Keyboards are low-bandwidth devices, so this slowdown 1696can help the device and guest to keep up and not lose events in case 1697events are arriving in bulk. Possible causes for the latter are flaky 1698network connections, or scripts for automated testing. 1699 1700@end table 1701ETEXI 1702 1703STEXI 1704@end table 1705ETEXI 1706ARCHHEADING(, QEMU_ARCH_I386) 1707 1708ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1709STEXI 1710@table @option 1711ETEXI 1712 1713DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1714 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1715 QEMU_ARCH_I386) 1716STEXI 1717@item -win2k-hack 1718@findex -win2k-hack 1719Use it when installing Windows 2000 to avoid a disk full bug. After 1720Windows 2000 is installed, you no longer need this option (this option 1721slows down the IDE transfers). 1722ETEXI 1723 1724HXCOMM Deprecated by -rtc 1725DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1726 1727DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1728 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1729 QEMU_ARCH_I386) 1730STEXI 1731@item -no-fd-bootchk 1732@findex -no-fd-bootchk 1733Disable boot signature checking for floppy disks in BIOS. May 1734be needed to boot from old floppy disks. 1735ETEXI 1736 1737DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1738 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1739STEXI 1740@item -no-acpi 1741@findex -no-acpi 1742Disable ACPI (Advanced Configuration and Power Interface) support. Use 1743it if your guest OS complains about ACPI problems (PC target machine 1744only). 1745ETEXI 1746 1747DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1748 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1749STEXI 1750@item -no-hpet 1751@findex -no-hpet 1752Disable HPET support. 1753ETEXI 1754 1755DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1756 "-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" 1757 " ACPI table description\n", QEMU_ARCH_I386) 1758STEXI 1759@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}]...] 1760@findex -acpitable 1761Add ACPI table with specified header fields and context from specified files. 1762For file=, take whole ACPI table from the specified files, including all 1763ACPI headers (possible overridden by other options). 1764For data=, only data 1765portion of the table is used, all header information is specified in the 1766command line. 1767If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1768fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1769to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1770spec. 1771ETEXI 1772 1773DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1774 "-smbios file=binary\n" 1775 " load SMBIOS entry from binary file\n" 1776 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1777 " [,uefi=on|off]\n" 1778 " specify SMBIOS type 0 fields\n" 1779 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1780 " [,uuid=uuid][,sku=str][,family=str]\n" 1781 " specify SMBIOS type 1 fields\n" 1782 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1783 " [,asset=str][,location=str]\n" 1784 " specify SMBIOS type 2 fields\n" 1785 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1786 " [,sku=str]\n" 1787 " specify SMBIOS type 3 fields\n" 1788 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1789 " [,asset=str][,part=str]\n" 1790 " specify SMBIOS type 4 fields\n" 1791 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1792 " [,asset=str][,part=str][,speed=%d]\n" 1793 " specify SMBIOS type 17 fields\n", 1794 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1795STEXI 1796@item -smbios file=@var{binary} 1797@findex -smbios 1798Load SMBIOS entry from binary file. 1799 1800@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1801Specify SMBIOS type 0 fields 1802 1803@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}] 1804Specify SMBIOS type 1 fields 1805 1806@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}] 1807Specify SMBIOS type 2 fields 1808 1809@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1810Specify SMBIOS type 3 fields 1811 1812@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1813Specify SMBIOS type 4 fields 1814 1815@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}] 1816Specify SMBIOS type 17 fields 1817ETEXI 1818 1819STEXI 1820@end table 1821ETEXI 1822DEFHEADING() 1823 1824DEFHEADING(Network options:) 1825STEXI 1826@table @option 1827ETEXI 1828 1829HXCOMM Legacy slirp options (now moved to -net user): 1830#ifdef CONFIG_SLIRP 1831DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1832DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1833DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1834#ifndef _WIN32 1835DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1836#endif 1837#endif 1838 1839DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1840#ifdef CONFIG_SLIRP 1841 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 1842 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 1843 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1844 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n" 1845 " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1846#ifndef _WIN32 1847 "[,smb=dir[,smbserver=addr]]\n" 1848#endif 1849 " configure a user mode network backend with ID 'str',\n" 1850 " its DHCP server and optional services\n" 1851#endif 1852#ifdef _WIN32 1853 "-netdev tap,id=str,ifname=name\n" 1854 " configure a host TAP network backend with ID 'str'\n" 1855#else 1856 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1857 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1858 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1859 " [,poll-us=n]\n" 1860 " configure a host TAP network backend with ID 'str'\n" 1861 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1862 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1863 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1864 " to deconfigure it\n" 1865 " use '[down]script=no' to disable script execution\n" 1866 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1867 " configure it\n" 1868 " use 'fd=h' to connect to an already opened TAP interface\n" 1869 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1870 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1871 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1872 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1873 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1874 " use vhost=on to enable experimental in kernel accelerator\n" 1875 " (only has effect for virtio guests which use MSIX)\n" 1876 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1877 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1878 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1879 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1880 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 1881 " spent on busy polling for vhost net\n" 1882 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1883 " configure a host TAP network backend with ID 'str' that is\n" 1884 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1885 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1886#endif 1887#ifdef __linux__ 1888 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1889 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1890 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1891 " [,rxcookie=rxcookie][,offset=offset]\n" 1892 " configure a network backend with ID 'str' connected to\n" 1893 " an Ethernet over L2TPv3 pseudowire.\n" 1894 " Linux kernel 3.3+ as well as most routers can talk\n" 1895 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1896 " VM to a router and even VM to Host. It is a nearly-universal\n" 1897 " standard (RFC3391). Note - this implementation uses static\n" 1898 " pre-configured tunnels (same as the Linux kernel).\n" 1899 " use 'src=' to specify source address\n" 1900 " use 'dst=' to specify destination address\n" 1901 " use 'udp=on' to specify udp encapsulation\n" 1902 " use 'srcport=' to specify source udp port\n" 1903 " use 'dstport=' to specify destination udp port\n" 1904 " use 'ipv6=on' to force v6\n" 1905 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1906 " well as a weak security measure\n" 1907 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1908 " use 'txcookie=0x012345678' to specify a txcookie\n" 1909 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1910 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1911 " use 'pincounter=on' to work around broken counter handling in peer\n" 1912 " use 'offset=X' to add an extra offset between header and data\n" 1913#endif 1914 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1915 " configure a network backend to connect to another network\n" 1916 " using a socket connection\n" 1917 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1918 " configure a network backend to connect to a multicast maddr and port\n" 1919 " use 'localaddr=addr' to specify the host address to send packets from\n" 1920 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1921 " configure a network backend to connect to another network\n" 1922 " using an UDP tunnel\n" 1923#ifdef CONFIG_VDE 1924 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1925 " configure a network backend to connect to port 'n' of a vde switch\n" 1926 " running on host and listening for incoming connections on 'socketpath'.\n" 1927 " Use group 'groupname' and mode 'octalmode' to change default\n" 1928 " ownership and permissions for communication port.\n" 1929#endif 1930#ifdef CONFIG_NETMAP 1931 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1932 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1933 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1934 " netmap device, defaults to '/dev/netmap')\n" 1935#endif 1936#ifdef CONFIG_POSIX 1937 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 1938 " configure a vhost-user network, backed by a chardev 'dev'\n" 1939#endif 1940 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n" 1941 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL) 1942DEF("nic", HAS_ARG, QEMU_OPTION_nic, 1943 "-nic [tap|bridge|" 1944#ifdef CONFIG_SLIRP 1945 "user|" 1946#endif 1947#ifdef __linux__ 1948 "l2tpv3|" 1949#endif 1950#ifdef CONFIG_VDE 1951 "vde|" 1952#endif 1953#ifdef CONFIG_NETMAP 1954 "netmap|" 1955#endif 1956#ifdef CONFIG_POSIX 1957 "vhost-user|" 1958#endif 1959 "socket][,option][,...][mac=macaddr]\n" 1960 " initialize an on-board / default host NIC (using MAC address\n" 1961 " macaddr) and connect it to the given host network backend\n" 1962 "-nic none use it alone to have zero network devices (the default is to\n" 1963 " provided a 'user' network connection)\n", 1964 QEMU_ARCH_ALL) 1965DEF("net", HAS_ARG, QEMU_OPTION_net, 1966 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1967 " configure or create an on-board (or machine default) NIC and\n" 1968 " connect it to hub 0 (please use -nic unless you need a hub)\n" 1969 "-net [" 1970#ifdef CONFIG_SLIRP 1971 "user|" 1972#endif 1973 "tap|" 1974 "bridge|" 1975#ifdef CONFIG_VDE 1976 "vde|" 1977#endif 1978#ifdef CONFIG_NETMAP 1979 "netmap|" 1980#endif 1981 "socket][,option][,option][,...]\n" 1982 " old way to initialize a host network interface\n" 1983 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 1984STEXI 1985@item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn] 1986@findex -nic 1987This option is a shortcut for configuring both the on-board (default) guest 1988NIC hardware and the host network backend in one go. The host backend options 1989are the same as with the corresponding @option{-netdev} options below. 1990The guest NIC model can be set with @option{model=@var{modelname}}. 1991Use @option{model=help} to list the available device types. 1992The hardware MAC address can be set with @option{mac=@var{macaddr}}. 1993 1994The following two example do exactly the same, to show how @option{-nic} can 1995be used to shorten the command line length (note that the e1000 is the default 1996on i386, so the @option{model=e1000} parameter could even be omitted here, too): 1997@example 1998qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32 1999qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32 2000@end example 2001 2002@item -nic none 2003Indicate that no network devices should be configured. It is used to override 2004the default configuration (default NIC with ``user'' host network backend) 2005which is activated if no other networking options are provided. 2006 2007@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 2008@findex -netdev 2009Configure user mode host network backend which requires no administrator 2010privilege to run. Valid options are: 2011 2012@table @option 2013@item id=@var{id} 2014Assign symbolic name for use in monitor commands. 2015 2016@item ipv4=on|off and ipv6=on|off 2017Specify that either IPv4 or IPv6 must be enabled. If neither is specified 2018both protocols are enabled. 2019 2020@item net=@var{addr}[/@var{mask}] 2021Set IP network address the guest will see. Optionally specify the netmask, 2022either in the form a.b.c.d or as number of valid top-most bits. Default is 202310.0.2.0/24. 2024 2025@item host=@var{addr} 2026Specify the guest-visible address of the host. Default is the 2nd IP in the 2027guest network, i.e. x.x.x.2. 2028 2029@item ipv6-net=@var{addr}[/@var{int}] 2030Set IPv6 network address the guest will see (default is fec0::/64). The 2031network prefix is given in the usual hexadecimal IPv6 address 2032notation. The prefix size is optional, and is given as the number of 2033valid top-most bits (default is 64). 2034 2035@item ipv6-host=@var{addr} 2036Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 2037the guest network, i.e. xxxx::2. 2038 2039@item restrict=on|off 2040If this option is enabled, the guest will be isolated, i.e. it will not be 2041able to contact the host and no guest IP packets will be routed over the host 2042to the outside. This option does not affect any explicitly set forwarding rules. 2043 2044@item hostname=@var{name} 2045Specifies the client hostname reported by the built-in DHCP server. 2046 2047@item dhcpstart=@var{addr} 2048Specify the first of the 16 IPs the built-in DHCP server can assign. Default 2049is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 2050 2051@item dns=@var{addr} 2052Specify the guest-visible address of the virtual nameserver. The address must 2053be different from the host address. Default is the 3rd IP in the guest network, 2054i.e. x.x.x.3. 2055 2056@item ipv6-dns=@var{addr} 2057Specify the guest-visible address of the IPv6 virtual nameserver. The address 2058must be different from the host address. Default is the 3rd IP in the guest 2059network, i.e. xxxx::3. 2060 2061@item dnssearch=@var{domain} 2062Provides an entry for the domain-search list sent by the built-in 2063DHCP server. More than one domain suffix can be transmitted by specifying 2064this option multiple times. If supported, this will cause the guest to 2065automatically try to append the given domain suffix(es) in case a domain name 2066can not be resolved. 2067 2068Example: 2069@example 2070qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org 2071@end example 2072 2073@item domainname=@var{domain} 2074Specifies the client domain name reported by the built-in DHCP server. 2075 2076@item tftp=@var{dir} 2077When using the user mode network stack, activate a built-in TFTP 2078server. The files in @var{dir} will be exposed as the root of a TFTP server. 2079The TFTP client on the guest must be configured in binary mode (use the command 2080@code{bin} of the Unix TFTP client). 2081 2082@item bootfile=@var{file} 2083When using the user mode network stack, broadcast @var{file} as the BOOTP 2084filename. In conjunction with @option{tftp}, this can be used to network boot 2085a guest from a local directory. 2086 2087Example (using pxelinux): 2088@example 2089qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \ 2090 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2091@end example 2092 2093@item smb=@var{dir}[,smbserver=@var{addr}] 2094When using the user mode network stack, activate a built-in SMB 2095server so that Windows OSes can access to the host files in @file{@var{dir}} 2096transparently. The IP address of the SMB server can be set to @var{addr}. By 2097default the 4th IP in the guest network is used, i.e. x.x.x.4. 2098 2099In the guest Windows OS, the line: 2100@example 210110.0.2.4 smbserver 2102@end example 2103must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2104or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2105 2106Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2107 2108Note that a SAMBA server must be installed on the host OS. 2109 2110@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2111Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2112the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2113@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2114given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2115be bound to a specific host interface. If no connection type is set, TCP is 2116used. This option can be given multiple times. 2117 2118For example, to redirect host X11 connection from screen 1 to guest 2119screen 0, use the following: 2120 2121@example 2122# on the host 2123qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 2124# this host xterm should open in the guest X11 server 2125xterm -display :1 2126@end example 2127 2128To redirect telnet connections from host port 5555 to telnet port on 2129the guest, use the following: 2130 2131@example 2132# on the host 2133qemu-system-i386 -nic user,hostfwd=tcp::5555-:23 2134telnet localhost 5555 2135@end example 2136 2137Then when you use on the host @code{telnet localhost 5555}, you 2138connect to the guest telnet server. 2139 2140@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2141@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2142Forward guest TCP connections to the IP address @var{server} on port @var{port} 2143to the character device @var{dev} or to a program executed by @var{cmd:command} 2144which gets spawned for each connection. This option can be given multiple times. 2145 2146You can either use a chardev directly and have that one used throughout QEMU's 2147lifetime, like in the following example: 2148 2149@example 2150# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2151# the guest accesses it 2152qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 2153@end example 2154 2155Or you can execute a command on every TCP connection established by the guest, 2156so that QEMU behaves similar to an inetd process for that virtual server: 2157 2158@example 2159# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2160# and connect the TCP stream to its stdin/stdout 2161qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2162@end example 2163 2164@end table 2165 2166Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 2167processed and applied to -net user. Mixing them with the new configuration 2168syntax gives undefined results. Their use for new applications is discouraged 2169as they will be removed from future versions. 2170 2171@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2172Configure a host TAP network backend with ID @var{id}. 2173 2174Use the network script @var{file} to configure it and the network script 2175@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2176automatically provides one. The default network configure script is 2177@file{/etc/qemu-ifup} and the default network deconfigure script is 2178@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2179to disable script execution. 2180 2181If running QEMU as an unprivileged user, use the network helper 2182@var{helper} to configure the TAP interface and attach it to the bridge. 2183The default network helper executable is @file{/path/to/qemu-bridge-helper} 2184and the default bridge device is @file{br0}. 2185 2186@option{fd}=@var{h} can be used to specify the handle of an already 2187opened host TAP interface. 2188 2189Examples: 2190 2191@example 2192#launch a QEMU instance with the default network script 2193qemu-system-i386 linux.img -nic tap 2194@end example 2195 2196@example 2197#launch a QEMU instance with two NICs, each one connected 2198#to a TAP device 2199qemu-system-i386 linux.img \ 2200 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \ 2201 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1 2202@end example 2203 2204@example 2205#launch a QEMU instance with the default network helper to 2206#connect a TAP device to bridge br0 2207qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \ 2208 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper" 2209@end example 2210 2211@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2212Connect a host TAP network interface to a host bridge device. 2213 2214Use the network helper @var{helper} to configure the TAP interface and 2215attach it to the bridge. The default network helper executable is 2216@file{/path/to/qemu-bridge-helper} and the default bridge 2217device is @file{br0}. 2218 2219Examples: 2220 2221@example 2222#launch a QEMU instance with the default network helper to 2223#connect a TAP device to bridge br0 2224qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1 2225@end example 2226 2227@example 2228#launch a QEMU instance with the default network helper to 2229#connect a TAP device to bridge qemubr0 2230qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1 2231@end example 2232 2233@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2234 2235This host network backend can be used to connect the guest's network to 2236another QEMU virtual machine using a TCP socket connection. If @option{listen} 2237is specified, QEMU waits for incoming connections on @var{port} 2238(@var{host} is optional). @option{connect} is used to connect to 2239another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2240specifies an already opened TCP socket. 2241 2242Example: 2243@example 2244# launch a first QEMU instance 2245qemu-system-i386 linux.img \ 2246 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2247 -netdev socket,id=n1,listen=:1234 2248# connect the network of this instance to the network of the first instance 2249qemu-system-i386 linux.img \ 2250 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2251 -netdev socket,id=n2,connect=127.0.0.1:1234 2252@end example 2253 2254@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2255 2256Configure a socket host network backend to share the guest's network traffic 2257with another QEMU virtual machines using a UDP multicast socket, effectively 2258making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. 2259NOTES: 2260@enumerate 2261@item 2262Several QEMU can be running on different hosts and share same bus (assuming 2263correct multicast setup for these hosts). 2264@item 2265mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2266@url{http://user-mode-linux.sf.net}. 2267@item 2268Use @option{fd=h} to specify an already opened UDP multicast socket. 2269@end enumerate 2270 2271Example: 2272@example 2273# launch one QEMU instance 2274qemu-system-i386 linux.img \ 2275 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2276 -netdev socket,id=n1,mcast=230.0.0.1:1234 2277# launch another QEMU instance on same "bus" 2278qemu-system-i386 linux.img \ 2279 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2280 -netdev socket,id=n2,mcast=230.0.0.1:1234 2281# launch yet another QEMU instance on same "bus" 2282qemu-system-i386 linux.img \ 2283 -device e1000,netdev=n3,macaddr=52:54:00:12:34:58 \ 2284 -netdev socket,id=n3,mcast=230.0.0.1:1234 2285@end example 2286 2287Example (User Mode Linux compat.): 2288@example 2289# launch QEMU instance (note mcast address selected is UML's default) 2290qemu-system-i386 linux.img \ 2291 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2292 -netdev socket,id=n1,mcast=239.192.168.1:1102 2293# launch UML 2294/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2295@end example 2296 2297Example (send packets from host's 1.2.3.4): 2298@example 2299qemu-system-i386 linux.img \ 2300 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2301 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2302@end example 2303 2304@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}] 2305Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a 2306popular protocol to transport Ethernet (and other Layer 2) data frames between 2307two systems. It is present in routers, firewalls and the Linux kernel 2308(from version 3.3 onwards). 2309 2310This transport allows a VM to communicate to another VM, router or firewall directly. 2311 2312@table @option 2313@item src=@var{srcaddr} 2314 source address (mandatory) 2315@item dst=@var{dstaddr} 2316 destination address (mandatory) 2317@item udp 2318 select udp encapsulation (default is ip). 2319@item srcport=@var{srcport} 2320 source udp port. 2321@item dstport=@var{dstport} 2322 destination udp port. 2323@item ipv6 2324 force v6, otherwise defaults to v4. 2325@item rxcookie=@var{rxcookie} 2326@itemx txcookie=@var{txcookie} 2327 Cookies are a weak form of security in the l2tpv3 specification. 2328Their function is mostly to prevent misconfiguration. By default they are 32 2329bit. 2330@item cookie64 2331 Set cookie size to 64 bit instead of the default 32 2332@item counter=off 2333 Force a 'cut-down' L2TPv3 with no counter as in 2334draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2335@item pincounter=on 2336 Work around broken counter handling in peer. This may also help on 2337networks which have packet reorder. 2338@item offset=@var{offset} 2339 Add an extra offset between header and data 2340@end table 2341 2342For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2343on the remote Linux host 1.2.3.4: 2344@example 2345# Setup tunnel on linux host using raw ip as encapsulation 2346# on 1.2.3.4 2347ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2348 encap udp udp_sport 16384 udp_dport 16384 2349ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2350 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2351ifconfig vmtunnel0 mtu 1500 2352ifconfig vmtunnel0 up 2353brctl addif br-lan vmtunnel0 2354 2355 2356# on 4.3.2.1 2357# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2358 2359qemu-system-i386 linux.img -device e1000,netdev=n1 \ 2360 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2361 2362@end example 2363 2364@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2365Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and 2366listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2367and MODE @var{octalmode} to change default ownership and permissions for 2368communication port. This option is only available if QEMU has been compiled 2369with vde support enabled. 2370 2371Example: 2372@example 2373# launch vde switch 2374vde_switch -F -sock /tmp/myswitch 2375# launch QEMU instance 2376qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch 2377@end example 2378 2379@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2380 2381Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2382be a unix domain socket backed one. The vhost-user uses a specifically defined 2383protocol to pass vhost ioctl replacement messages to an application on the other 2384end of the socket. On non-MSIX guests, the feature can be forced with 2385@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2386be created for multiqueue vhost-user. 2387 2388Example: 2389@example 2390qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2391 -numa node,memdev=mem \ 2392 -chardev socket,id=chr0,path=/path/to/socket \ 2393 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2394 -device virtio-net-pci,netdev=net0 2395@end example 2396 2397@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}] 2398 2399Create a hub port on the emulated hub with ID @var{hubid}. 2400 2401The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a 2402single netdev. Alternatively, you can also connect the hubport to another 2403netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option. 2404 2405@item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2406@findex -net 2407Legacy option to configure or create an on-board (or machine default) Network 2408Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. 2409the default hub), or to the netdev @var{nd}. 2410The NIC is an e1000 by default on the PC target. Optionally, the MAC address 2411can be changed to @var{mac}, the device address set to @var{addr} (PCI cards 2412only), and a @var{name} can be assigned for use in monitor commands. 2413Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2414that the card should have; this option currently only affects virtio cards; set 2415@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2416NIC is created. QEMU can emulate several different models of network card. 2417Use @code{-net nic,model=help} for a list of available devices for your target. 2418 2419@item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}] 2420Configure a host network backend (with the options corresponding to the same 2421@option{-netdev} option) and connect it to the emulated hub 0 (the default 2422hub). Use @var{name} to specify the name of the hub port. 2423ETEXI 2424 2425STEXI 2426@end table 2427ETEXI 2428DEFHEADING() 2429 2430DEFHEADING(Character device options:) 2431 2432DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2433 "-chardev help\n" 2434 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2435 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2436 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n" 2437 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2438 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n" 2439 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2440 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2441 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2442 " [,logfile=PATH][,logappend=on|off]\n" 2443 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2444 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2445 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2446 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2447 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2448 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2449#ifdef _WIN32 2450 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2451 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2452#else 2453 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2454 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2455#endif 2456#ifdef CONFIG_BRLAPI 2457 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2458#endif 2459#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2460 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2461 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2462 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2463#endif 2464#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2465 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2466 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2467#endif 2468#if defined(CONFIG_SPICE) 2469 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2470 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2471#endif 2472 , QEMU_ARCH_ALL 2473) 2474 2475STEXI 2476 2477The general form of a character device option is: 2478@table @option 2479@item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}] 2480@findex -chardev 2481Backend is one of: 2482@option{null}, 2483@option{socket}, 2484@option{udp}, 2485@option{msmouse}, 2486@option{vc}, 2487@option{ringbuf}, 2488@option{file}, 2489@option{pipe}, 2490@option{console}, 2491@option{serial}, 2492@option{pty}, 2493@option{stdio}, 2494@option{braille}, 2495@option{tty}, 2496@option{parallel}, 2497@option{parport}, 2498@option{spicevmc}, 2499@option{spiceport}. 2500The specific backend will determine the applicable options. 2501 2502Use @code{-chardev help} to print all available chardev backend types. 2503 2504All devices must have an id, which can be any string up to 127 characters long. 2505It is used to uniquely identify this device in other command line directives. 2506 2507A character device may be used in multiplexing mode by multiple front-ends. 2508Specify @option{mux=on} to enable this mode. 2509A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2510backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2511If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2512create a multiplexer with your specified ID, and you can then configure multiple 2513front ends to use that chardev ID for their input/output. Up to four different 2514front ends can be connected to a single multiplexed chardev. (Without 2515multiplexing enabled, a chardev can only be used by a single front end.) 2516For instance you could use this to allow a single stdio chardev to be used by 2517two serial ports and the QEMU monitor: 2518 2519@example 2520-chardev stdio,mux=on,id=char0 \ 2521-mon chardev=char0,mode=readline \ 2522-serial chardev:char0 \ 2523-serial chardev:char0 2524@end example 2525 2526You can have more than one multiplexer in a system configuration; for instance 2527you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2528multiplexed between the QEMU monitor and a parallel port: 2529 2530@example 2531-chardev stdio,mux=on,id=char0 \ 2532-mon chardev=char0,mode=readline \ 2533-parallel chardev:char0 \ 2534-chardev tcp,...,mux=on,id=char1 \ 2535-serial chardev:char1 \ 2536-serial chardev:char1 2537@end example 2538 2539When you're using a multiplexed character device, some escape sequences are 2540interpreted in the input. @xref{mux_keys, Keys in the character backend 2541multiplexer}. 2542 2543Note that some other command line options may implicitly create multiplexed 2544character backends; for instance @option{-serial mon:stdio} creates a 2545multiplexed stdio backend connected to the serial port and the QEMU monitor, 2546and @option{-nographic} also multiplexes the console and the monitor to 2547stdio. 2548 2549There is currently no support for multiplexing in the other direction 2550(where a single QEMU front end takes input and output from multiple chardevs). 2551 2552Every backend supports the @option{logfile} option, which supplies the path 2553to a file to record all data transmitted via the backend. The @option{logappend} 2554option controls whether the log file will be truncated or appended to when 2555opened. 2556 2557@end table 2558 2559The available backends are: 2560 2561@table @option 2562@item -chardev null,id=@var{id} 2563A void device. This device will not emit any data, and will drop any data it 2564receives. The null backend does not take any options. 2565 2566@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,reconnect=@var{seconds}][,tls-creds=@var{id}] 2567 2568Create a two-way stream socket, which can be either a TCP or a unix socket. A 2569unix socket will be created if @option{path} is specified. Behaviour is 2570undefined if TCP options are specified for a unix socket. 2571 2572@option{server} specifies that the socket shall be a listening socket. 2573 2574@option{nowait} specifies that QEMU should not block waiting for a client to 2575connect to a listening socket. 2576 2577@option{telnet} specifies that traffic on the socket should interpret telnet 2578escape sequences. 2579 2580@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2581the remote end goes away. qemu will delay this many seconds and then attempt 2582to reconnect. Zero disables reconnecting, and is the default. 2583 2584@option{tls-creds} requests enablement of the TLS protocol for encryption, 2585and specifies the id of the TLS credentials to use for the handshake. The 2586credentials must be previously created with the @option{-object tls-creds} 2587argument. 2588 2589TCP and unix socket options are given below: 2590 2591@table @option 2592 2593@item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay] 2594 2595@option{host} for a listening socket specifies the local address to be bound. 2596For a connecting socket species the remote host to connect to. @option{host} is 2597optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2598 2599@option{port} for a listening socket specifies the local port to be bound. For a 2600connecting socket specifies the port on the remote host to connect to. 2601@option{port} can be given as either a port number or a service name. 2602@option{port} is required. 2603 2604@option{to} is only relevant to listening sockets. If it is specified, and 2605@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2606to and including @option{to} until it succeeds. @option{to} must be specified 2607as a port number. 2608 2609@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2610If neither is specified the socket may use either protocol. 2611 2612@option{nodelay} disables the Nagle algorithm. 2613 2614@item unix options: path=@var{path} 2615 2616@option{path} specifies the local path of the unix socket. @option{path} is 2617required. 2618 2619@end table 2620 2621@item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6] 2622 2623Sends all traffic from the guest to a remote host over UDP. 2624 2625@option{host} specifies the remote host to connect to. If not specified it 2626defaults to @code{localhost}. 2627 2628@option{port} specifies the port on the remote host to connect to. @option{port} 2629is required. 2630 2631@option{localaddr} specifies the local address to bind to. If not specified it 2632defaults to @code{0.0.0.0}. 2633 2634@option{localport} specifies the local port to bind to. If not specified any 2635available local port will be used. 2636 2637@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2638If neither is specified the device may use either protocol. 2639 2640@item -chardev msmouse,id=@var{id} 2641 2642Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2643take any options. 2644 2645@item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]] 2646 2647Connect to a QEMU text console. @option{vc} may optionally be given a specific 2648size. 2649 2650@option{width} and @option{height} specify the width and height respectively of 2651the console, in pixels. 2652 2653@option{cols} and @option{rows} specify that the console be sized to fit a text 2654console with the given dimensions. 2655 2656@item -chardev ringbuf,id=@var{id}[,size=@var{size}] 2657 2658Create a ring buffer with fixed size @option{size}. 2659@var{size} must be a power of two and defaults to @code{64K}. 2660 2661@item -chardev file,id=@var{id},path=@var{path} 2662 2663Log all traffic received from the guest to a file. 2664 2665@option{path} specifies the path of the file to be opened. This file will be 2666created if it does not already exist, and overwritten if it does. @option{path} 2667is required. 2668 2669@item -chardev pipe,id=@var{id},path=@var{path} 2670 2671Create a two-way connection to the guest. The behaviour differs slightly between 2672Windows hosts and other hosts: 2673 2674On Windows, a single duplex pipe will be created at 2675@file{\\.pipe\@option{path}}. 2676 2677On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2678@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2679received by the guest. Data written by the guest can be read from 2680@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2681be present. 2682 2683@option{path} forms part of the pipe path as described above. @option{path} is 2684required. 2685 2686@item -chardev console,id=@var{id} 2687 2688Send traffic from the guest to QEMU's standard output. @option{console} does not 2689take any options. 2690 2691@option{console} is only available on Windows hosts. 2692 2693@item -chardev serial,id=@var{id},path=@option{path} 2694 2695Send traffic from the guest to a serial device on the host. 2696 2697On Unix hosts serial will actually accept any tty device, 2698not only serial lines. 2699 2700@option{path} specifies the name of the serial device to open. 2701 2702@item -chardev pty,id=@var{id} 2703 2704Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2705not take any options. 2706 2707@option{pty} is not available on Windows hosts. 2708 2709@item -chardev stdio,id=@var{id}[,signal=on|off] 2710Connect to standard input and standard output of the QEMU process. 2711 2712@option{signal} controls if signals are enabled on the terminal, that includes 2713exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2714default, use @option{signal=off} to disable it. 2715 2716@item -chardev braille,id=@var{id} 2717 2718Connect to a local BrlAPI server. @option{braille} does not take any options. 2719 2720@item -chardev tty,id=@var{id},path=@var{path} 2721 2722@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2723DragonFlyBSD hosts. It is an alias for @option{serial}. 2724 2725@option{path} specifies the path to the tty. @option{path} is required. 2726 2727@item -chardev parallel,id=@var{id},path=@var{path} 2728@itemx -chardev parport,id=@var{id},path=@var{path} 2729 2730@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2731 2732Connect to a local parallel port. 2733 2734@option{path} specifies the path to the parallel port device. @option{path} is 2735required. 2736 2737@item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name} 2738 2739@option{spicevmc} is only available when spice support is built in. 2740 2741@option{debug} debug level for spicevmc 2742 2743@option{name} name of spice channel to connect to 2744 2745Connect to a spice virtual machine channel, such as vdiport. 2746 2747@item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name} 2748 2749@option{spiceport} is only available when spice support is built in. 2750 2751@option{debug} debug level for spicevmc 2752 2753@option{name} name of spice port to connect to 2754 2755Connect to a spice port, allowing a Spice client to handle the traffic 2756identified by a name (preferably a fqdn). 2757ETEXI 2758 2759STEXI 2760@end table 2761ETEXI 2762DEFHEADING() 2763 2764DEFHEADING(Bluetooth(R) options:) 2765STEXI 2766@table @option 2767ETEXI 2768 2769DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2770 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2771 "-bt hci,host[:id]\n" \ 2772 " use host's HCI with the given name\n" \ 2773 "-bt hci[,vlan=n]\n" \ 2774 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2775 "-bt vhci[,vlan=n]\n" \ 2776 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2777 "-bt device:dev[,vlan=n]\n" \ 2778 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2779 QEMU_ARCH_ALL) 2780STEXI 2781@item -bt hci[...] 2782@findex -bt 2783Defines the function of the corresponding Bluetooth HCI. -bt options 2784are matched with the HCIs present in the chosen machine type. For 2785example when emulating a machine with only one HCI built into it, only 2786the first @code{-bt hci[...]} option is valid and defines the HCI's 2787logic. The Transport Layer is decided by the machine type. Currently 2788the machines @code{n800} and @code{n810} have one HCI and all other 2789machines have none. 2790 2791@anchor{bt-hcis} 2792The following three types are recognized: 2793 2794@table @option 2795@item -bt hci,null 2796(default) The corresponding Bluetooth HCI assumes no internal logic 2797and will not respond to any HCI commands or emit events. 2798 2799@item -bt hci,host[:@var{id}] 2800(@code{bluez} only) The corresponding HCI passes commands / events 2801to / from the physical HCI identified by the name @var{id} (default: 2802@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2803capable systems like Linux. 2804 2805@item -bt hci[,vlan=@var{n}] 2806Add a virtual, standard HCI that will participate in the Bluetooth 2807scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2808VLANs, devices inside a bluetooth network @var{n} can only communicate 2809with other devices in the same network (scatternet). 2810@end table 2811 2812@item -bt vhci[,vlan=@var{n}] 2813(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2814to the host bluetooth stack instead of to the emulated target. This 2815allows the host and target machines to participate in a common scatternet 2816and communicate. Requires the Linux @code{vhci} driver installed. Can 2817be used as following: 2818 2819@example 2820qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2821@end example 2822 2823@item -bt device:@var{dev}[,vlan=@var{n}] 2824Emulate a bluetooth device @var{dev} and place it in network @var{n} 2825(default @code{0}). QEMU can only emulate one type of bluetooth devices 2826currently: 2827 2828@table @option 2829@item keyboard 2830Virtual wireless keyboard implementing the HIDP bluetooth profile. 2831@end table 2832ETEXI 2833 2834STEXI 2835@end table 2836ETEXI 2837DEFHEADING() 2838 2839#ifdef CONFIG_TPM 2840DEFHEADING(TPM device options:) 2841 2842DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2843 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2844 " use path to provide path to a character device; default is /dev/tpm0\n" 2845 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2846 " not provided it will be searched for in /sys/class/misc/tpm?/device\n" 2847 "-tpmdev emulator,id=id,chardev=dev\n" 2848 " configure the TPM device using chardev backend\n", 2849 QEMU_ARCH_ALL) 2850STEXI 2851 2852The general form of a TPM device option is: 2853@table @option 2854 2855@item -tpmdev @var{backend},id=@var{id}[,@var{options}] 2856@findex -tpmdev 2857 2858The specific backend type will determine the applicable options. 2859The @code{-tpmdev} option creates the TPM backend and requires a 2860@code{-device} option that specifies the TPM frontend interface model. 2861 2862Use @code{-tpmdev help} to print all available TPM backend types. 2863 2864@end table 2865 2866The available backends are: 2867 2868@table @option 2869 2870@item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path} 2871 2872(Linux-host only) Enable access to the host's TPM using the passthrough 2873driver. 2874 2875@option{path} specifies the path to the host's TPM device, i.e., on 2876a Linux host this would be @code{/dev/tpm0}. 2877@option{path} is optional and by default @code{/dev/tpm0} is used. 2878 2879@option{cancel-path} specifies the path to the host TPM device's sysfs 2880entry allowing for cancellation of an ongoing TPM command. 2881@option{cancel-path} is optional and by default QEMU will search for the 2882sysfs entry to use. 2883 2884Some notes about using the host's TPM with the passthrough driver: 2885 2886The TPM device accessed by the passthrough driver must not be 2887used by any other application on the host. 2888 2889Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2890the VM's firmware (BIOS/UEFI) will not be able to initialize the 2891TPM again and may therefore not show a TPM-specific menu that would 2892otherwise allow the user to configure the TPM, e.g., allow the user to 2893enable/disable or activate/deactivate the TPM. 2894Further, if TPM ownership is released from within a VM then the host's TPM 2895will get disabled and deactivated. To enable and activate the 2896TPM again afterwards, the host has to be rebooted and the user is 2897required to enter the firmware's menu to enable and activate the TPM. 2898If the TPM is left disabled and/or deactivated most TPM commands will fail. 2899 2900To create a passthrough TPM use the following two options: 2901@example 2902-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2903@end example 2904Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2905@code{tpmdev=tpm0} in the device option. 2906 2907@item -tpmdev emulator,id=@var{id},chardev=@var{dev} 2908 2909(Linux-host only) Enable access to a TPM emulator using Unix domain socket based 2910chardev backend. 2911 2912@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server. 2913 2914To create a TPM emulator backend device with chardev socket backend: 2915@example 2916 2917-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0 2918 2919@end example 2920 2921ETEXI 2922 2923STEXI 2924@end table 2925ETEXI 2926DEFHEADING() 2927 2928#endif 2929 2930DEFHEADING(Linux/Multiboot boot specific:) 2931STEXI 2932 2933When using these options, you can use a given Linux or Multiboot 2934kernel without installing it in the disk image. It can be useful 2935for easier testing of various kernels. 2936 2937@table @option 2938ETEXI 2939 2940DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2941 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2942STEXI 2943@item -kernel @var{bzImage} 2944@findex -kernel 2945Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2946or in multiboot format. 2947ETEXI 2948 2949DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2950 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2951STEXI 2952@item -append @var{cmdline} 2953@findex -append 2954Use @var{cmdline} as kernel command line 2955ETEXI 2956 2957DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2958 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2959STEXI 2960@item -initrd @var{file} 2961@findex -initrd 2962Use @var{file} as initial ram disk. 2963 2964@item -initrd "@var{file1} arg=foo,@var{file2}" 2965 2966This syntax is only available with multiboot. 2967 2968Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2969first module. 2970ETEXI 2971 2972DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2973 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2974STEXI 2975@item -dtb @var{file} 2976@findex -dtb 2977Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2978on boot. 2979ETEXI 2980 2981STEXI 2982@end table 2983ETEXI 2984DEFHEADING() 2985 2986DEFHEADING(Debug/Expert options:) 2987STEXI 2988@table @option 2989ETEXI 2990 2991DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 2992 "-fw_cfg [name=]<name>,file=<file>\n" 2993 " add named fw_cfg entry with contents from file\n" 2994 "-fw_cfg [name=]<name>,string=<str>\n" 2995 " add named fw_cfg entry with contents from string\n", 2996 QEMU_ARCH_ALL) 2997STEXI 2998 2999@item -fw_cfg [name=]@var{name},file=@var{file} 3000@findex -fw_cfg 3001Add named fw_cfg entry with contents from file @var{file}. 3002 3003@item -fw_cfg [name=]@var{name},string=@var{str} 3004Add named fw_cfg entry with contents from string @var{str}. 3005 3006The terminating NUL character of the contents of @var{str} will not be 3007included as part of the fw_cfg item data. To insert contents with 3008embedded NUL characters, you have to use the @var{file} parameter. 3009 3010The fw_cfg entries are passed by QEMU through to the guest. 3011 3012Example: 3013@example 3014 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 3015@end example 3016creates an fw_cfg entry named opt/com.mycompany/blob with contents 3017from ./my_blob.bin. 3018 3019ETEXI 3020 3021DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 3022 "-serial dev redirect the serial port to char device 'dev'\n", 3023 QEMU_ARCH_ALL) 3024STEXI 3025@item -serial @var{dev} 3026@findex -serial 3027Redirect the virtual serial port to host character device 3028@var{dev}. The default device is @code{vc} in graphical mode and 3029@code{stdio} in non graphical mode. 3030 3031This option can be used several times to simulate up to 4 serial 3032ports. 3033 3034Use @code{-serial none} to disable all serial ports. 3035 3036Available character devices are: 3037@table @option 3038@item vc[:@var{W}x@var{H}] 3039Virtual console. Optionally, a width and height can be given in pixel with 3040@example 3041vc:800x600 3042@end example 3043It is also possible to specify width or height in characters: 3044@example 3045vc:80Cx24C 3046@end example 3047@item pty 3048[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3049@item none 3050No device is allocated. 3051@item null 3052void device 3053@item chardev:@var{id} 3054Use a named character device defined with the @code{-chardev} option. 3055@item /dev/XXX 3056[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3057parameters are set according to the emulated ones. 3058@item /dev/parport@var{N} 3059[Linux only, parallel port only] Use host parallel port 3060@var{N}. Currently SPP and EPP parallel port features can be used. 3061@item file:@var{filename} 3062Write output to @var{filename}. No character can be read. 3063@item stdio 3064[Unix only] standard input/output 3065@item pipe:@var{filename} 3066name pipe @var{filename} 3067@item COM@var{n} 3068[Windows only] Use host serial port @var{n} 3069@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3070This implements UDP Net Console. 3071When @var{remote_host} or @var{src_ip} are not specified 3072they default to @code{0.0.0.0}. 3073When not using a specified @var{src_port} a random port is automatically chosen. 3074 3075If you just want a simple readonly console you can use @code{netcat} or 3076@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3077@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3078will appear in the netconsole session. 3079 3080If you plan to send characters back via netconsole or you want to stop 3081and start QEMU a lot of times, you should have QEMU use the same 3082source port each time by using something like @code{-serial 3083udp::4555@@:4556} to QEMU. Another approach is to use a patched 3084version of netcat which can listen to a TCP port and send and receive 3085characters via udp. If you have a patched version of netcat which 3086activates telnet remote echo and single char transfer, then you can 3087use the following options to set up a netcat redirector to allow 3088telnet on port 5555 to access the QEMU port. 3089@table @code 3090@item QEMU Options: 3091-serial udp::4555@@:4556 3092@item netcat options: 3093-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3094@item telnet options: 3095localhost 5555 3096@end table 3097 3098@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3099The TCP Net Console has two modes of operation. It can send the serial 3100I/O to a location or wait for a connection from a location. By default 3101the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3102the @var{server} option QEMU will wait for a client socket application 3103to connect to the port before continuing, unless the @code{nowait} 3104option was specified. The @code{nodelay} option disables the Nagle buffering 3105algorithm. The @code{reconnect} option only applies if @var{noserver} is 3106set, if the connection goes down it will attempt to reconnect at the 3107given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3108one TCP connection at a time is accepted. You can use @code{telnet} to 3109connect to the corresponding character device. 3110@table @code 3111@item Example to send tcp console to 192.168.0.2 port 4444 3112-serial tcp:192.168.0.2:4444 3113@item Example to listen and wait on port 4444 for connection 3114-serial tcp::4444,server 3115@item Example to not wait and listen on ip 192.168.0.100 port 4444 3116-serial tcp:192.168.0.100:4444,server,nowait 3117@end table 3118 3119@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3120The telnet protocol is used instead of raw tcp sockets. The options 3121work the same as if you had specified @code{-serial tcp}. The 3122difference is that the port acts like a telnet server or client using 3123telnet option negotiation. This will also allow you to send the 3124MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3125sequence. Typically in unix telnet you do it with Control-] and then 3126type "send break" followed by pressing the enter key. 3127 3128@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3129A unix domain socket is used instead of a tcp socket. The option works the 3130same as if you had specified @code{-serial tcp} except the unix domain socket 3131@var{path} is used for connections. 3132 3133@item mon:@var{dev_string} 3134This is a special option to allow the monitor to be multiplexed onto 3135another serial port. The monitor is accessed with key sequence of 3136@key{Control-a} and then pressing @key{c}. 3137@var{dev_string} should be any one of the serial devices specified 3138above. An example to multiplex the monitor onto a telnet server 3139listening on port 4444 would be: 3140@table @code 3141@item -serial mon:telnet::4444,server,nowait 3142@end table 3143When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3144QEMU any more but will be passed to the guest instead. 3145 3146@item braille 3147Braille device. This will use BrlAPI to display the braille output on a real 3148or fake device. 3149 3150@item msmouse 3151Three button serial mouse. Configure the guest to use Microsoft protocol. 3152@end table 3153ETEXI 3154 3155DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3156 "-parallel dev redirect the parallel port to char device 'dev'\n", 3157 QEMU_ARCH_ALL) 3158STEXI 3159@item -parallel @var{dev} 3160@findex -parallel 3161Redirect the virtual parallel port to host device @var{dev} (same 3162devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3163be used to use hardware devices connected on the corresponding host 3164parallel port. 3165 3166This option can be used several times to simulate up to 3 parallel 3167ports. 3168 3169Use @code{-parallel none} to disable all parallel ports. 3170ETEXI 3171 3172DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3173 "-monitor dev redirect the monitor to char device 'dev'\n", 3174 QEMU_ARCH_ALL) 3175STEXI 3176@item -monitor @var{dev} 3177@findex -monitor 3178Redirect the monitor to host device @var{dev} (same devices as the 3179serial port). 3180The default device is @code{vc} in graphical mode and @code{stdio} in 3181non graphical mode. 3182Use @code{-monitor none} to disable the default monitor. 3183ETEXI 3184DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3185 "-qmp dev like -monitor but opens in 'control' mode\n", 3186 QEMU_ARCH_ALL) 3187STEXI 3188@item -qmp @var{dev} 3189@findex -qmp 3190Like -monitor but opens in 'control' mode. 3191ETEXI 3192DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3193 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3194 QEMU_ARCH_ALL) 3195STEXI 3196@item -qmp-pretty @var{dev} 3197@findex -qmp-pretty 3198Like -qmp but uses pretty JSON formatting. 3199ETEXI 3200 3201DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3202 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL) 3203STEXI 3204@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]] 3205@findex -mon 3206Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing 3207easing human reading and debugging. 3208ETEXI 3209 3210DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3211 "-debugcon dev redirect the debug console to char device 'dev'\n", 3212 QEMU_ARCH_ALL) 3213STEXI 3214@item -debugcon @var{dev} 3215@findex -debugcon 3216Redirect the debug console to host device @var{dev} (same devices as the 3217serial port). The debug console is an I/O port which is typically port 32180xe9; writing to that I/O port sends output to this device. 3219The default device is @code{vc} in graphical mode and @code{stdio} in 3220non graphical mode. 3221ETEXI 3222 3223DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3224 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3225STEXI 3226@item -pidfile @var{file} 3227@findex -pidfile 3228Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3229from a script. 3230ETEXI 3231 3232DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3233 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3234STEXI 3235@item -singlestep 3236@findex -singlestep 3237Run the emulation in single step mode. 3238ETEXI 3239 3240DEF("preconfig", 0, QEMU_OPTION_preconfig, \ 3241 "--preconfig pause QEMU before machine is initialized (experimental)\n", 3242 QEMU_ARCH_ALL) 3243STEXI 3244@item --preconfig 3245@findex --preconfig 3246Pause QEMU for interactive configuration before the machine is created, 3247which allows querying and configuring properties that will affect 3248machine initialization. Use QMP command 'x-exit-preconfig' to exit 3249the preconfig state and move to the next state (i.e. run guest if -S 3250isn't used or pause the second time if -S is used). This option is 3251experimental. 3252ETEXI 3253 3254DEF("S", 0, QEMU_OPTION_S, \ 3255 "-S freeze CPU at startup (use 'c' to start execution)\n", 3256 QEMU_ARCH_ALL) 3257STEXI 3258@item -S 3259@findex -S 3260Do not start CPU at startup (you must type 'c' in the monitor). 3261ETEXI 3262 3263DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3264 "-realtime [mlock=on|off]\n" 3265 " run qemu with realtime features\n" 3266 " mlock=on|off controls mlock support (default: on)\n", 3267 QEMU_ARCH_ALL) 3268STEXI 3269@item -realtime mlock=on|off 3270@findex -realtime 3271Run qemu with realtime features. 3272mlocking qemu and guest memory can be enabled via @option{mlock=on} 3273(enabled by default). 3274ETEXI 3275 3276DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, 3277 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" 3278 " run qemu with overcommit hints\n" 3279 " mem-lock=on|off controls memory lock support (default: off)\n" 3280 " cpu-pm=on|off controls cpu power management (default: off)\n", 3281 QEMU_ARCH_ALL) 3282STEXI 3283@item -overcommit mem-lock=on|off 3284@item -overcommit cpu-pm=on|off 3285@findex -overcommit 3286Run qemu with hints about host resource overcommit. The default is 3287to assume that host overcommits all resources. 3288 3289Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled 3290by default). This works when host memory is not overcommitted and reduces the 3291worst-case latency for guest. This is equivalent to @option{realtime}. 3292 3293Guest ability to manage power state of host cpus (increasing latency for other 3294processes on the same host cpu, but decreasing latency for guest) can be 3295enabled via @option{cpu-pm=on} (disabled by default). This works best when 3296host CPU is not overcommitted. When used, host estimates of CPU cycle and power 3297utilization will be incorrect, not taking into account guest idle time. 3298ETEXI 3299 3300DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3301 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3302STEXI 3303@item -gdb @var{dev} 3304@findex -gdb 3305Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3306connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3307stdio are reasonable use case. The latter is allowing to start QEMU from 3308within gdb and establish the connection via a pipe: 3309@example 3310(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3311@end example 3312ETEXI 3313 3314DEF("s", 0, QEMU_OPTION_s, \ 3315 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3316 QEMU_ARCH_ALL) 3317STEXI 3318@item -s 3319@findex -s 3320Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3321(@pxref{gdb_usage}). 3322ETEXI 3323 3324DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3325 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3326 QEMU_ARCH_ALL) 3327STEXI 3328@item -d @var{item1}[,...] 3329@findex -d 3330Enable logging of specified items. Use '-d help' for a list of log items. 3331ETEXI 3332 3333DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3334 "-D logfile output log to logfile (default stderr)\n", 3335 QEMU_ARCH_ALL) 3336STEXI 3337@item -D @var{logfile} 3338@findex -D 3339Output log in @var{logfile} instead of to stderr 3340ETEXI 3341 3342DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3343 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3344 QEMU_ARCH_ALL) 3345STEXI 3346@item -dfilter @var{range1}[,...] 3347@findex -dfilter 3348Filter debug output to that relevant to a range of target addresses. The filter 3349spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3350@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3351addresses and sizes required. For example: 3352@example 3353 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3354@end example 3355Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3356the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3357block starting at 0xffffffc00005f000. 3358ETEXI 3359 3360DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3361 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3362 QEMU_ARCH_ALL) 3363STEXI 3364@item -L @var{path} 3365@findex -L 3366Set the directory for the BIOS, VGA BIOS and keymaps. 3367 3368To list all the data directories, use @code{-L help}. 3369ETEXI 3370 3371DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3372 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3373STEXI 3374@item -bios @var{file} 3375@findex -bios 3376Set the filename for the BIOS. 3377ETEXI 3378 3379DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3380 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3381STEXI 3382@item -enable-kvm 3383@findex -enable-kvm 3384Enable KVM full virtualization support. This option is only available 3385if KVM support is enabled when compiling. 3386ETEXI 3387 3388DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \ 3389 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386) 3390STEXI 3391@item -enable-hax 3392@findex -enable-hax 3393Enable HAX (Hardware-based Acceleration eXecution) support. This option 3394is only available if HAX support is enabled when compiling. HAX is only 3395applicable to MAC and Windows platform, and thus does not conflict with 3396KVM. This option is deprecated, use @option{-accel hax} instead. 3397ETEXI 3398 3399DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3400 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3401DEF("xen-create", 0, QEMU_OPTION_xen_create, 3402 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3403 " warning: should not be used when xend is in use\n", 3404 QEMU_ARCH_ALL) 3405DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3406 "-xen-attach attach to existing xen domain\n" 3407 " xend will use this when starting QEMU\n", 3408 QEMU_ARCH_ALL) 3409DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict, 3410 "-xen-domid-restrict restrict set of available xen operations\n" 3411 " to specified domain id. (Does not affect\n" 3412 " xenpv machine type).\n", 3413 QEMU_ARCH_ALL) 3414STEXI 3415@item -xen-domid @var{id} 3416@findex -xen-domid 3417Specify xen guest domain @var{id} (XEN only). 3418@item -xen-create 3419@findex -xen-create 3420Create domain using xen hypercalls, bypassing xend. 3421Warning: should not be used when xend is in use (XEN only). 3422@item -xen-attach 3423@findex -xen-attach 3424Attach to existing xen domain. 3425xend will use this when starting QEMU (XEN only). 3426@findex -xen-domid-restrict 3427Restrict set of available xen operations to specified domain id (XEN only). 3428ETEXI 3429 3430DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3431 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3432STEXI 3433@item -no-reboot 3434@findex -no-reboot 3435Exit instead of rebooting. 3436ETEXI 3437 3438DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3439 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3440STEXI 3441@item -no-shutdown 3442@findex -no-shutdown 3443Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3444This allows for instance switching to monitor to commit changes to the 3445disk image. 3446ETEXI 3447 3448DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3449 "-loadvm [tag|id]\n" \ 3450 " start right away with a saved state (loadvm in monitor)\n", 3451 QEMU_ARCH_ALL) 3452STEXI 3453@item -loadvm @var{file} 3454@findex -loadvm 3455Start right away with a saved state (@code{loadvm} in monitor) 3456ETEXI 3457 3458#ifndef _WIN32 3459DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3460 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3461#endif 3462STEXI 3463@item -daemonize 3464@findex -daemonize 3465Daemonize the QEMU process after initialization. QEMU will not detach from 3466standard IO until it is ready to receive connections on any of its devices. 3467This option is a useful way for external programs to launch QEMU without having 3468to cope with initialization race conditions. 3469ETEXI 3470 3471DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3472 "-option-rom rom load a file, rom, into the option ROM space\n", 3473 QEMU_ARCH_ALL) 3474STEXI 3475@item -option-rom @var{file} 3476@findex -option-rom 3477Load the contents of @var{file} as an option ROM. 3478This option is useful to load things like EtherBoot. 3479ETEXI 3480 3481HXCOMM Silently ignored for compatibility 3482DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3483 3484HXCOMM Options deprecated by -rtc 3485DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 3486DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3487 3488DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3489 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3490 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3491 QEMU_ARCH_ALL) 3492 3493STEXI 3494 3495@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3496@findex -rtc 3497Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3498UTC or local time, respectively. @code{localtime} is required for correct date in 3499MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3500format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3501 3502By default the RTC is driven by the host system time. This allows using of the 3503RTC as accurate reference clock inside the guest, specifically if the host 3504time is smoothly following an accurate external reference clock, e.g. via NTP. 3505If you want to isolate the guest time from the host, you can set @option{clock} 3506to @code{rt} instead. To even prevent it from progressing during suspension, 3507you can set it to @code{vm}. 3508 3509Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3510specifically with Windows' ACPI HAL. This option will try to figure out how 3511many timer interrupts were not processed by the Windows guest and will 3512re-inject them. 3513ETEXI 3514 3515DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3516 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3517 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3518 " instruction, enable aligning the host and virtual clocks\n" \ 3519 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3520STEXI 3521@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3522@findex -icount 3523Enable virtual instruction counter. The virtual cpu will execute one 3524instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3525then the virtual cpu speed will be automatically adjusted to keep virtual 3526time within a few seconds of real time. 3527 3528When the virtual cpu is sleeping, the virtual time will advance at default 3529speed unless @option{sleep=on|off} is specified. 3530With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3531instantly whenever the virtual cpu goes to sleep mode and will not advance 3532if no timer is enabled. This behavior give deterministic execution times from 3533the guest point of view. 3534 3535Note that while this option can give deterministic behavior, it does not 3536provide cycle accurate emulation. Modern CPUs contain superscalar out of 3537order cores with complex cache hierarchies. The number of instructions 3538executed often has little or no correlation with actual performance. 3539 3540@option{align=on} will activate the delay algorithm which will try 3541to synchronise the host clock and the virtual clock. The goal is to 3542have a guest running at the real frequency imposed by the shift option. 3543Whenever the guest clock is behind the host clock and if 3544@option{align=on} is specified then we print a message to the user 3545to inform about the delay. 3546Currently this option does not work when @option{shift} is @code{auto}. 3547Note: The sync algorithm will work for those shift values for which 3548the guest clock runs ahead of the host clock. Typically this happens 3549when the shift value is high (how high depends on the host machine). 3550 3551When @option{rr} option is specified deterministic record/replay is enabled. 3552Replay log is written into @var{filename} file in record mode and 3553read from this file in replay mode. 3554 3555Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3556at the start of execution recording. In replay mode this option is used 3557to load the initial VM state. 3558ETEXI 3559 3560DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3561 "-watchdog model\n" \ 3562 " enable virtual hardware watchdog [default=none]\n", 3563 QEMU_ARCH_ALL) 3564STEXI 3565@item -watchdog @var{model} 3566@findex -watchdog 3567Create a virtual hardware watchdog device. Once enabled (by a guest 3568action), the watchdog must be periodically polled by an agent inside 3569the guest or else the guest will be restarted. Choose a model for 3570which your guest has drivers. 3571 3572The @var{model} is the model of hardware watchdog to emulate. Use 3573@code{-watchdog help} to list available hardware models. Only one 3574watchdog can be enabled for a guest. 3575 3576The following models may be available: 3577@table @option 3578@item ib700 3579iBASE 700 is a very simple ISA watchdog with a single timer. 3580@item i6300esb 3581Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3582dual-timer watchdog. 3583@item diag288 3584A virtual watchdog for s390x backed by the diagnose 288 hypercall 3585(currently KVM only). 3586@end table 3587ETEXI 3588 3589DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3590 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \ 3591 " action when watchdog fires [default=reset]\n", 3592 QEMU_ARCH_ALL) 3593STEXI 3594@item -watchdog-action @var{action} 3595@findex -watchdog-action 3596 3597The @var{action} controls what QEMU will do when the watchdog timer 3598expires. 3599The default is 3600@code{reset} (forcefully reset the guest). 3601Other possible actions are: 3602@code{shutdown} (attempt to gracefully shutdown the guest), 3603@code{poweroff} (forcefully poweroff the guest), 3604@code{inject-nmi} (inject a NMI into the guest), 3605@code{pause} (pause the guest), 3606@code{debug} (print a debug message and continue), or 3607@code{none} (do nothing). 3608 3609Note that the @code{shutdown} action requires that the guest responds 3610to ACPI signals, which it may not be able to do in the sort of 3611situations where the watchdog would have expired, and thus 3612@code{-watchdog-action shutdown} is not recommended for production use. 3613 3614Examples: 3615 3616@table @code 3617@item -watchdog i6300esb -watchdog-action pause 3618@itemx -watchdog ib700 3619@end table 3620ETEXI 3621 3622DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3623 "-echr chr set terminal escape character instead of ctrl-a\n", 3624 QEMU_ARCH_ALL) 3625STEXI 3626 3627@item -echr @var{numeric_ascii_value} 3628@findex -echr 3629Change the escape character used for switching to the monitor when using 3630monitor and serial sharing. The default is @code{0x01} when using the 3631@code{-nographic} option. @code{0x01} is equal to pressing 3632@code{Control-a}. You can select a different character from the ascii 3633control keys where 1 through 26 map to Control-a through Control-z. For 3634instance you could use the either of the following to change the escape 3635character to Control-t. 3636@table @code 3637@item -echr 0x14 3638@itemx -echr 20 3639@end table 3640ETEXI 3641 3642DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3643 "-virtioconsole c\n" \ 3644 " set virtio console\n", QEMU_ARCH_ALL) 3645STEXI 3646@item -virtioconsole @var{c} 3647@findex -virtioconsole 3648Set virtio console. 3649This option is deprecated, please use @option{-device virtconsole} instead. 3650ETEXI 3651 3652DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3653 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3654STEXI 3655@item -show-cursor 3656@findex -show-cursor 3657Show cursor. 3658ETEXI 3659 3660DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3661 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3662STEXI 3663@item -tb-size @var{n} 3664@findex -tb-size 3665Set TB size. 3666ETEXI 3667 3668DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3669 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3670 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3671 "-incoming unix:socketpath\n" \ 3672 " prepare for incoming migration, listen on\n" \ 3673 " specified protocol and socket address\n" \ 3674 "-incoming fd:fd\n" \ 3675 "-incoming exec:cmdline\n" \ 3676 " accept incoming migration on given file descriptor\n" \ 3677 " or from given external command\n" \ 3678 "-incoming defer\n" \ 3679 " wait for the URI to be specified via migrate_incoming\n", 3680 QEMU_ARCH_ALL) 3681STEXI 3682@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3683@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3684@findex -incoming 3685Prepare for incoming migration, listen on a given tcp port. 3686 3687@item -incoming unix:@var{socketpath} 3688Prepare for incoming migration, listen on a given unix socket. 3689 3690@item -incoming fd:@var{fd} 3691Accept incoming migration from a given filedescriptor. 3692 3693@item -incoming exec:@var{cmdline} 3694Accept incoming migration as an output from specified external command. 3695 3696@item -incoming defer 3697Wait for the URI to be specified via migrate_incoming. The monitor can 3698be used to change settings (such as migration parameters) prior to issuing 3699the migrate_incoming to allow the migration to begin. 3700ETEXI 3701 3702DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3703 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3704STEXI 3705@item -only-migratable 3706@findex -only-migratable 3707Only allow migratable devices. Devices will not be allowed to enter an 3708unmigratable state. 3709ETEXI 3710 3711DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3712 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3713STEXI 3714@item -nodefaults 3715@findex -nodefaults 3716Don't create default devices. Normally, QEMU sets the default devices like serial 3717port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3718CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3719default devices. 3720ETEXI 3721 3722#ifndef _WIN32 3723DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3724 "-chroot dir chroot to dir just before starting the VM\n", 3725 QEMU_ARCH_ALL) 3726#endif 3727STEXI 3728@item -chroot @var{dir} 3729@findex -chroot 3730Immediately before starting guest execution, chroot to the specified 3731directory. Especially useful in combination with -runas. 3732ETEXI 3733 3734#ifndef _WIN32 3735DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3736 "-runas user change to user id user just before starting the VM\n" \ 3737 " user can be numeric uid:gid instead\n", 3738 QEMU_ARCH_ALL) 3739#endif 3740STEXI 3741@item -runas @var{user} 3742@findex -runas 3743Immediately before starting guest execution, drop root privileges, switching 3744to the specified user. 3745ETEXI 3746 3747DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3748 "-prom-env variable=value\n" 3749 " set OpenBIOS nvram variables\n", 3750 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3751STEXI 3752@item -prom-env @var{variable}=@var{value} 3753@findex -prom-env 3754Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3755ETEXI 3756DEF("semihosting", 0, QEMU_OPTION_semihosting, 3757 "-semihosting semihosting mode\n", 3758 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3759 QEMU_ARCH_MIPS) 3760STEXI 3761@item -semihosting 3762@findex -semihosting 3763Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3764ETEXI 3765DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3766 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3767 " semihosting configuration\n", 3768QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3769QEMU_ARCH_MIPS) 3770STEXI 3771@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3772@findex -semihosting-config 3773Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3774@table @option 3775@item target=@code{native|gdb|auto} 3776Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3777or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3778during debug sessions and @code{native} otherwise. 3779@item arg=@var{str1},arg=@var{str2},... 3780Allows the user to pass input arguments, and can be used multiple times to build 3781up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3782command line is still supported for backward compatibility. If both the 3783@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3784specified, the former is passed to semihosting as it always takes precedence. 3785@end table 3786ETEXI 3787DEF("old-param", 0, QEMU_OPTION_old_param, 3788 "-old-param old param mode\n", QEMU_ARCH_ARM) 3789STEXI 3790@item -old-param 3791@findex -old-param (ARM) 3792Old param mode (ARM only). 3793ETEXI 3794 3795DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3796 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \ 3797 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \ 3798 " Enable seccomp mode 2 system call filter (default 'off').\n" \ 3799 " use 'obsolete' to allow obsolete system calls that are provided\n" \ 3800 " by the kernel, but typically no longer used by modern\n" \ 3801 " C library implementations.\n" \ 3802 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \ 3803 " its privileges by blacklisting all set*uid|gid system calls.\n" \ 3804 " The value 'children' will deny set*uid|gid system calls for\n" \ 3805 " main QEMU process but will allow forks and execves to run unprivileged\n" \ 3806 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \ 3807 " blacklisting *fork and execve\n" \ 3808 " use 'resourcecontrol' to disable process affinity and schedular priority\n", 3809 QEMU_ARCH_ALL) 3810STEXI 3811@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}] 3812@findex -sandbox 3813Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3814disable it. The default is 'off'. 3815@table @option 3816@item obsolete=@var{string} 3817Enable Obsolete system calls 3818@item elevateprivileges=@var{string} 3819Disable set*uid|gid system calls 3820@item spawn=@var{string} 3821Disable *fork and execve 3822@item resourcecontrol=@var{string} 3823Disable process affinity and schedular priority 3824@end table 3825ETEXI 3826 3827DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3828 "-readconfig <file>\n", QEMU_ARCH_ALL) 3829STEXI 3830@item -readconfig @var{file} 3831@findex -readconfig 3832Read device configuration from @var{file}. This approach is useful when you want to spawn 3833QEMU process with many command line options but you don't want to exceed the command line 3834character limit. 3835ETEXI 3836DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3837 "-writeconfig <file>\n" 3838 " read/write config file\n", QEMU_ARCH_ALL) 3839STEXI 3840@item -writeconfig @var{file} 3841@findex -writeconfig 3842Write device configuration to @var{file}. The @var{file} can be either filename to save 3843command line and device configuration into file or dash @code{-}) character to print the 3844output to stdout. This can be later used as input file for @code{-readconfig} option. 3845ETEXI 3846HXCOMM Deprecated, same as -no-user-config 3847DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL) 3848DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3849 "-no-user-config\n" 3850 " do not load default user-provided config files at startup\n", 3851 QEMU_ARCH_ALL) 3852STEXI 3853@item -no-user-config 3854@findex -no-user-config 3855The @code{-no-user-config} option makes QEMU not load any of the user-provided 3856config files on @var{sysconfdir}. 3857ETEXI 3858DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3859 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3860 " specify tracing options\n", 3861 QEMU_ARCH_ALL) 3862STEXI 3863HXCOMM This line is not accurate, as some sub-options are backend-specific but 3864HXCOMM HX does not support conditional compilation of text. 3865@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 3866@findex -trace 3867@include qemu-option-trace.texi 3868ETEXI 3869 3870HXCOMM Internal use 3871DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3872DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3873 3874#ifdef __linux__ 3875DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3876 "-enable-fips enable FIPS 140-2 compliance\n", 3877 QEMU_ARCH_ALL) 3878#endif 3879STEXI 3880@item -enable-fips 3881@findex -enable-fips 3882Enable FIPS 140-2 compliance mode. 3883ETEXI 3884 3885HXCOMM Deprecated by -machine accel=tcg property 3886DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3887 3888DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3889 "-msg timestamp[=on|off]\n" 3890 " change the format of messages\n" 3891 " on|off controls leading timestamps (default:on)\n", 3892 QEMU_ARCH_ALL) 3893STEXI 3894@item -msg timestamp[=on|off] 3895@findex -msg 3896prepend a timestamp to each log message.(default:on) 3897ETEXI 3898 3899DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3900 "-dump-vmstate <file>\n" 3901 " Output vmstate information in JSON format to file.\n" 3902 " Use the scripts/vmstate-static-checker.py file to\n" 3903 " check for possible regressions in migration code\n" 3904 " by comparing two such vmstate dumps.\n", 3905 QEMU_ARCH_ALL) 3906STEXI 3907@item -dump-vmstate @var{file} 3908@findex -dump-vmstate 3909Dump json-encoded vmstate information for current machine type to file 3910in @var{file} 3911ETEXI 3912 3913DEF("enable-sync-profile", 0, QEMU_OPTION_enable_sync_profile, 3914 "-enable-sync-profile\n" 3915 " enable synchronization profiling\n", 3916 QEMU_ARCH_ALL) 3917STEXI 3918@item -enable-sync-profile 3919@findex -enable-sync-profile 3920Enable synchronization profiling. 3921ETEXI 3922 3923STEXI 3924@end table 3925ETEXI 3926DEFHEADING() 3927 3928DEFHEADING(Generic object creation:) 3929STEXI 3930@table @option 3931ETEXI 3932 3933DEF("object", HAS_ARG, QEMU_OPTION_object, 3934 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3935 " create a new object of type TYPENAME setting properties\n" 3936 " in the order they are specified. Note that the 'id'\n" 3937 " property must be set. These objects are placed in the\n" 3938 " '/objects' path.\n", 3939 QEMU_ARCH_ALL) 3940STEXI 3941@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3942@findex -object 3943Create a new object of type @var{typename} setting properties 3944in the order they are specified. Note that the 'id' 3945property must be set. These objects are placed in the 3946'/objects' path. 3947 3948@table @option 3949 3950@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} 3951 3952Creates a memory file backend object, which can be used to back 3953the guest RAM with huge pages. 3954 3955The @option{id} parameter is a unique ID that will be used to reference this 3956memory region when configuring the @option{-numa} argument. 3957 3958The @option{size} option provides the size of the memory region, and accepts 3959common suffixes, eg @option{500M}. 3960 3961The @option{mem-path} provides the path to either a shared memory or huge page 3962filesystem mount. 3963 3964The @option{share} boolean option determines whether the memory 3965region is marked as private to QEMU, or shared. The latter allows 3966a co-operating external process to access the QEMU memory region. 3967 3968The @option{share} is also required for pvrdma devices due to 3969limitations in the RDMA API provided by Linux. 3970 3971Setting share=on might affect the ability to configure NUMA 3972bindings for the memory backend under some circumstances, see 3973Documentation/vm/numa_memory_policy.txt on the Linux kernel 3974source tree for additional details. 3975 3976Setting the @option{discard-data} boolean option to @var{on} 3977indicates that file contents can be destroyed when QEMU exits, 3978to avoid unnecessarily flushing data to the backing file. Note 3979that @option{discard-data} is only an optimization, and QEMU 3980might not discard file contents if it aborts unexpectedly or is 3981terminated using SIGKILL. 3982 3983The @option{merge} boolean option enables memory merge, also known as 3984MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for 3985memory deduplication. 3986 3987Setting the @option{dump} boolean option to @var{off} excludes the memory from 3988core dumps. This feature is also known as MADV_DONTDUMP. 3989 3990The @option{prealloc} boolean option enables memory preallocation. 3991 3992The @option{host-nodes} option binds the memory range to a list of NUMA host 3993nodes. 3994 3995The @option{policy} option sets the NUMA policy to one of the following values: 3996 3997@table @option 3998@item @var{default} 3999default host policy 4000 4001@item @var{preferred} 4002prefer the given host node list for allocation 4003 4004@item @var{bind} 4005restrict memory allocation to the given host node list 4006 4007@item @var{interleave} 4008interleave memory allocations across the given host node list 4009@end table 4010 4011The @option{align} option specifies the base address alignment when 4012QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg 4013@option{2M}. Some backend store specified by @option{mem-path} 4014requires an alignment different than the default one used by QEMU, eg 4015the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In 4016such cases, users can specify the required alignment via this option. 4017 4018The @option{pmem} option specifies whether the backing file specified 4019by @option{mem-path} is in host persistent memory that can be accessed 4020using the SNIA NVM programming model (e.g. Intel NVDIMM). 4021If @option{pmem} is set to 'on', QEMU will take necessary operations to 4022guarantee the persistence of its own writes to @option{mem-path} 4023(e.g. in vNVDIMM label emulation and live migration). 4024 4025@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} 4026 4027Creates a memory backend object, which can be used to back the guest RAM. 4028Memory backend objects offer more control than the @option{-m} option that is 4029traditionally used to define guest RAM. Please refer to 4030@option{memory-backend-file} for a description of the options. 4031 4032@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} 4033 4034Creates an anonymous memory file backend object, which allows QEMU to 4035share the memory with an external process (e.g. when using 4036vhost-user). The memory is allocated with memfd and optional 4037sealing. (Linux only) 4038 4039The @option{seal} option creates a sealed-file, that will block 4040further resizing the memory ('on' by default). 4041 4042The @option{hugetlb} option specify the file to be created resides in 4043the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with 4044the @option{hugetlb} option, the @option{hugetlbsize} option specify 4045the hugetlb page size on systems that support multiple hugetlb page 4046sizes (it must be a power of 2 value supported by the system). 4047 4048In some versions of Linux, the @option{hugetlb} option is incompatible 4049with the @option{seal} option (requires at least Linux 4.16). 4050 4051Please refer to @option{memory-backend-file} for a description of the 4052other options. 4053 4054@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4055 4056Creates a random number generator backend which obtains entropy from 4057a device on the host. The @option{id} parameter is a unique ID that 4058will be used to reference this entropy backend from the @option{virtio-rng} 4059device. The @option{filename} parameter specifies which file to obtain 4060entropy from and if omitted defaults to @option{/dev/random}. 4061 4062@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4063 4064Creates a random number generator backend which obtains entropy from 4065an external daemon running on the host. The @option{id} parameter is 4066a unique ID that will be used to reference this entropy backend from 4067the @option{virtio-rng} device. The @option{chardev} parameter is 4068the unique ID of a character device backend that provides the connection 4069to the RNG daemon. 4070 4071@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4072 4073Creates a TLS anonymous credentials object, which can be used to provide 4074TLS support on network backends. The @option{id} parameter is a unique 4075ID which network backends will use to access the credentials. The 4076@option{endpoint} is either @option{server} or @option{client} depending 4077on whether the QEMU network backend that uses the credentials will be 4078acting as a client or as a server. If @option{verify-peer} is enabled 4079(the default) then once the handshake is completed, the peer credentials 4080will be verified, though this is a no-op for anonymous credentials. 4081 4082The @var{dir} parameter tells QEMU where to find the credential 4083files. For server endpoints, this directory may contain a file 4084@var{dh-params.pem} providing diffie-hellman parameters to use 4085for the TLS server. If the file is missing, QEMU will generate 4086a set of DH parameters at startup. This is a computationally 4087expensive operation that consumes random pool entropy, so it is 4088recommended that a persistent set of parameters be generated 4089upfront and saved. 4090 4091@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] 4092 4093Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide 4094TLS support on network backends. The @option{id} parameter is a unique 4095ID which network backends will use to access the credentials. The 4096@option{endpoint} is either @option{server} or @option{client} depending 4097on whether the QEMU network backend that uses the credentials will be 4098acting as a client or as a server. For clients only, @option{username} 4099is the username which will be sent to the server. If omitted 4100it defaults to ``qemu''. 4101 4102The @var{dir} parameter tells QEMU where to find the keys file. 4103It is called ``@var{dir}/keys.psk'' and contains ``username:key'' 4104pairs. This file can most easily be created using the GnuTLS 4105@code{psktool} program. 4106 4107For server endpoints, @var{dir} may also contain a file 4108@var{dh-params.pem} providing diffie-hellman parameters to use 4109for the TLS server. If the file is missing, QEMU will generate 4110a set of DH parameters at startup. This is a computationally 4111expensive operation that consumes random pool entropy, so it is 4112recommended that a persistent set of parameters be generated 4113up front and saved. 4114 4115@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} 4116 4117Creates a TLS anonymous credentials object, which can be used to provide 4118TLS support on network backends. The @option{id} parameter is a unique 4119ID which network backends will use to access the credentials. The 4120@option{endpoint} is either @option{server} or @option{client} depending 4121on whether the QEMU network backend that uses the credentials will be 4122acting as a client or as a server. If @option{verify-peer} is enabled 4123(the default) then once the handshake is completed, the peer credentials 4124will be verified. With x509 certificates, this implies that the clients 4125must be provided with valid client certificates too. 4126 4127The @var{dir} parameter tells QEMU where to find the credential 4128files. For server endpoints, this directory may contain a file 4129@var{dh-params.pem} providing diffie-hellman parameters to use 4130for the TLS server. If the file is missing, QEMU will generate 4131a set of DH parameters at startup. This is a computationally 4132expensive operation that consumes random pool entropy, so it is 4133recommended that a persistent set of parameters be generated 4134upfront and saved. 4135 4136For x509 certificate credentials the directory will contain further files 4137providing the x509 certificates. The certificates must be stored 4138in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4139@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4140@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4141 4142For the @var{server-key.pem} and @var{client-key.pem} files which 4143contain sensitive private keys, it is possible to use an encrypted 4144version by providing the @var{passwordid} parameter. This provides 4145the ID of a previously created @code{secret} object containing the 4146password for decryption. 4147 4148The @var{priority} parameter allows to override the global default 4149priority used by gnutls. This can be useful if the system administrator 4150needs to use a weaker set of crypto priorities for QEMU without 4151potentially forcing the weakness onto all applications. Or conversely 4152if one wants wants a stronger default for QEMU than for all other 4153applications, they can do this through this parameter. Its format is 4154a gnutls priority string as described at 4155@url{https://gnutls.org/manual/html_node/Priority-Strings.html}. 4156 4157@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4158 4159Interval @var{t} can't be 0, this filter batches the packet delivery: all 4160packets arriving in a given interval on netdev @var{netdevid} are delayed 4161until the end of the interval. Interval is in microseconds. 4162@option{status} is optional that indicate whether the netfilter is 4163on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4164 4165queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4166 4167@option{all}: the filter is attached both to the receive and the transmit 4168 queue of the netdev (default). 4169 4170@option{rx}: the filter is attached to the receive queue of the netdev, 4171 where it will receive packets sent to the netdev. 4172 4173@option{tx}: the filter is attached to the transmit queue of the netdev, 4174 where it will receive packets sent by the netdev. 4175 4176@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4177 4178filter-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. 4179 4180@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4181 4182filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4183@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag, 4184filter-redirector will redirect packet with vnet_hdr_len. 4185Create a filter-redirector we need to differ outdev id from indev id, id can not 4186be the same. we can just use indev or outdev, but at least one of indev or outdev 4187need to be specified. 4188 4189@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support] 4190 4191Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4192secondary from primary to keep secondary tcp connection,and rewrite 4193tcp packet to primary from secondary make tcp packet can be handled by 4194client.if it has the vnet_hdr_support flag, we can parse packet with vnet header. 4195 4196usage: 4197colo secondary: 4198-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4199-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4200-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4201 4202@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4203 4204Dump the network traffic on netdev @var{dev} to the file specified by 4205@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4206The file format is libpcap, so it can be analyzed with tools such as tcpdump 4207or Wireshark. 4208 4209@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support] 4210 4211Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4212secondary packet. If the packets are same, we will output primary 4213packet to outdev@var{chardevid}, else we will notify colo-frame 4214do checkpoint and send primary packet to outdev@var{chardevid}. 4215if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len. 4216 4217we must use it with the help of filter-mirror and filter-redirector. 4218 4219@example 4220 4221primary: 4222-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4223-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4224-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4225-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4226-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4227-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4228-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4229-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4230-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4231-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4232-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4233-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4234 4235secondary: 4236-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4237-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4238-chardev socket,id=red0,host=3.3.3.3,port=9003 4239-chardev socket,id=red1,host=3.3.3.3,port=9004 4240-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4241-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4242 4243@end example 4244 4245If you want to know the detail of above command line, you can read 4246the colo-compare git log. 4247 4248@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4249 4250Creates a cryptodev backend which executes crypto opreation from 4251the QEMU cipher APIS. The @var{id} parameter is 4252a unique ID that will be used to reference this cryptodev backend from 4253the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4254which specify the queue number of cryptodev backend, the default of 4255@var{queues} is 1. 4256 4257@example 4258 4259 # qemu-system-x86_64 \ 4260 [...] \ 4261 -object cryptodev-backend-builtin,id=cryptodev0 \ 4262 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4263 [...] 4264@end example 4265 4266@item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}] 4267 4268Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}. 4269The @var{id} parameter is a unique ID that will be used to reference this 4270cryptodev backend from the @option{virtio-crypto} device. 4271The chardev should be a unix domain socket backed one. The vhost-user uses 4272a specifically defined protocol to pass vhost ioctl replacement messages 4273to an application on the other end of the socket. 4274The @var{queues} parameter is optional, which specify the queue number 4275of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1. 4276 4277@example 4278 4279 # qemu-system-x86_64 \ 4280 [...] \ 4281 -chardev socket,id=chardev0,path=/path/to/socket \ 4282 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \ 4283 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4284 [...] 4285@end example 4286 4287@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4288@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4289 4290Defines a secret to store a password, encryption key, or some other sensitive 4291data. The sensitive data can either be passed directly via the @var{data} 4292parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4293parameter is insecure unless the sensitive data is encrypted. 4294 4295The sensitive data can be provided in raw format (the default), or base64. 4296When encoded as JSON, the raw format only supports valid UTF-8 characters, 4297so base64 is recommended for sending binary data. QEMU will convert from 4298which ever format is provided to the format it needs internally. eg, an 4299RBD password can be provided in raw format, even though it will be base64 4300encoded when passed onto the RBD sever. 4301 4302For added protection, it is possible to encrypt the data associated with 4303a secret using the AES-256-CBC cipher. Use of encryption is indicated 4304by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4305parameter provides the ID of a previously defined secret that contains 4306the AES-256 decryption key. This key should be 32-bytes long and be 4307base64 encoded. The @var{iv} parameter provides the random initialization 4308vector used for encryption of this particular secret and should be a 4309base64 encrypted string of the 16-byte IV. 4310 4311The simplest (insecure) usage is to provide the secret inline 4312 4313@example 4314 4315 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4316 4317@end example 4318 4319The simplest secure usage is to provide the secret via a file 4320 4321 # printf "letmein" > mypasswd.txt 4322 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4323 4324For greater security, AES-256-CBC should be used. To illustrate usage, 4325consider the openssl command line tool which can encrypt the data. Note 4326that when encrypting, the plaintext must be padded to the cipher block 4327size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4328 4329First a master key needs to be created in base64 encoding: 4330 4331@example 4332 # openssl rand -base64 32 > key.b64 4333 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4334@end example 4335 4336Each secret to be encrypted needs to have a random initialization vector 4337generated. These do not need to be kept secret 4338 4339@example 4340 # openssl rand -base64 16 > iv.b64 4341 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4342@end example 4343 4344The secret to be defined can now be encrypted, in this case we're 4345telling openssl to base64 encode the result, but it could be left 4346as raw bytes if desired. 4347 4348@example 4349 # SECRET=$(printf "letmein" | 4350 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4351@end example 4352 4353When launching QEMU, create a master secret pointing to @code{key.b64} 4354and specify that to be used to decrypt the user password. Pass the 4355contents of @code{iv.b64} to the second secret 4356 4357@example 4358 # $QEMU \ 4359 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4360 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4361 data=$SECRET,iv=$(<iv.b64) 4362@end example 4363 4364@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}] 4365 4366Create a Secure Encrypted Virtualization (SEV) guest object, which can be used 4367to provide the guest memory encryption support on AMD processors. 4368 4369When memory encryption is enabled, one of the physical address bit (aka the 4370C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos} 4371is used to provide the C-bit position. The C-bit position is Host family dependent 4372hence user must provide this value. On EPYC, the value should be 47. 4373 4374When memory encryption is enabled, we loose certain bits in physical address space. 4375The @option{reduced-phys-bits} is used to provide the number of bits we loose in 4376physical address space. Similar to C-bit, the value is Host family dependent. 4377On EPYC, the value should be 5. 4378 4379The @option{sev-device} provides the device file to use for communicating with 4380the SEV firmware running inside AMD Secure Processor. The default device is 4381'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are 4382created by CCP driver. 4383 4384The @option{policy} provides the guest policy to be enforced by the SEV firmware 4385and restrict what configuration and operational commands can be performed on this 4386guest by the hypervisor. The policy should be provided by the guest owner and is 4387bound to the guest and cannot be changed throughout the lifetime of the guest. 4388The default is 0. 4389 4390If guest @option{policy} allows sharing the key with another SEV guest then 4391@option{handle} can be use to provide handle of the guest from which to share 4392the key. 4393 4394The @option{dh-cert-file} and @option{session-file} provides the guest owner's 4395Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters 4396are used for establishing a cryptographic session with the guest owner to 4397negotiate keys used for attestation. The file must be encoded in base64. 4398 4399e.g to launch a SEV guest 4400@example 4401 # $QEMU \ 4402 ...... 4403 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ 4404 -machine ...,memory-encryption=sev0 4405 ..... 4406 4407@end example 4408@end table 4409 4410ETEXI 4411 4412 4413HXCOMM This is the last statement. Insert new options before this line! 4414STEXI 4415@end table 4416ETEXI 4417
