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("device", HAS_ARG, QEMU_OPTION_device, 458 "-device driver[,prop[=value][,...]]\n" 459 " add device (based on driver)\n" 460 " prop=value,... sets driver properties\n" 461 " use '-device help' to print all possible drivers\n" 462 " use '-device driver,help' to print all possible properties\n", 463 QEMU_ARCH_ALL) 464STEXI 465@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 466@findex -device 467Add device @var{driver}. @var{prop}=@var{value} sets driver 468properties. Valid properties depend on the driver. To get help on 469possible drivers and properties, use @code{-device help} and 470@code{-device @var{driver},help}. 471 472Some drivers are: 473@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}] 474 475Add an IPMI BMC. This is a simulation of a hardware management 476interface processor that normally sits on a system. It provides 477a watchdog and the ability to reset and power control the system. 478You need to connect this to an IPMI interface to make it useful 479 480The IPMI slave address to use for the BMC. The default is 0x20. 481This address is the BMC's address on the I2C network of management 482controllers. If you don't know what this means, it is safe to ignore 483it. 484 485@table @option 486@item bmc=@var{id} 487The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 488@item slave_addr=@var{val} 489Define slave address to use for the BMC. The default is 0x20. 490@item sdrfile=@var{file} 491file containing raw Sensor Data Records (SDR) data. The default is none. 492@item fruareasize=@var{val} 493size of a Field Replaceable Unit (FRU) area. The default is 1024. 494@item frudatafile=@var{file} 495file containing raw Field Replaceable Unit (FRU) inventory data. The default is none. 496@end table 497 498@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 499 500Add a connection to an external IPMI BMC simulator. Instead of 501locally emulating the BMC like the above item, instead connect 502to an external entity that provides the IPMI services. 503 504A connection is made to an external BMC simulator. If you do this, it 505is strongly recommended that you use the "reconnect=" chardev option 506to reconnect to the simulator if the connection is lost. Note that if 507this is not used carefully, it can be a security issue, as the 508interface has the ability to send resets, NMIs, and power off the VM. 509It's best if QEMU makes a connection to an external simulator running 510on a secure port on localhost, so neither the simulator nor QEMU is 511exposed to any outside network. 512 513See the "lanserv/README.vm" file in the OpenIPMI library for more 514details on the external interface. 515 516@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 517 518Add a KCS IPMI interafce on the ISA bus. This also adds a 519corresponding ACPI and SMBIOS entries, if appropriate. 520 521@table @option 522@item bmc=@var{id} 523The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 524@item ioport=@var{val} 525Define the I/O address of the interface. The default is 0xca0 for KCS. 526@item irq=@var{val} 527Define the interrupt to use. The default is 5. To disable interrupts, 528set this to 0. 529@end table 530 531@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 532 533Like the KCS interface, but defines a BT interface. The default port is 5340xe4 and the default interrupt is 5. 535 536ETEXI 537 538DEF("name", HAS_ARG, QEMU_OPTION_name, 539 "-name string1[,process=string2][,debug-threads=on|off]\n" 540 " set the name of the guest\n" 541 " string1 sets the window title and string2 the process name (on Linux)\n" 542 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 543 " NOTE: The thread names are for debugging and not a stable API.\n", 544 QEMU_ARCH_ALL) 545STEXI 546@item -name @var{name} 547@findex -name 548Sets the @var{name} of the guest. 549This name will be displayed in the SDL window caption. 550The @var{name} will also be used for the VNC server. 551Also optionally set the top visible process name in Linux. 552Naming of individual threads can also be enabled on Linux to aid debugging. 553ETEXI 554 555DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 556 "-uuid %08x-%04x-%04x-%04x-%012x\n" 557 " specify machine UUID\n", QEMU_ARCH_ALL) 558STEXI 559@item -uuid @var{uuid} 560@findex -uuid 561Set system UUID. 562ETEXI 563 564STEXI 565@end table 566ETEXI 567DEFHEADING() 568 569DEFHEADING(Block device options:) 570STEXI 571@table @option 572ETEXI 573 574DEF("fda", HAS_ARG, QEMU_OPTION_fda, 575 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 576DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 577STEXI 578@item -fda @var{file} 579@itemx -fdb @var{file} 580@findex -fda 581@findex -fdb 582Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 583ETEXI 584 585DEF("hda", HAS_ARG, QEMU_OPTION_hda, 586 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 587DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 588DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 589 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 590DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 591STEXI 592@item -hda @var{file} 593@itemx -hdb @var{file} 594@itemx -hdc @var{file} 595@itemx -hdd @var{file} 596@findex -hda 597@findex -hdb 598@findex -hdc 599@findex -hdd 600Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 601ETEXI 602 603DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 604 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 605 QEMU_ARCH_ALL) 606STEXI 607@item -cdrom @var{file} 608@findex -cdrom 609Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 610@option{-cdrom} at the same time). You can use the host CD-ROM by 611using @file{/dev/cdrom} as filename (@pxref{host_drives}). 612ETEXI 613 614DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev, 615 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n" 616 " [,cache.direct=on|off][,cache.no-flush=on|off]\n" 617 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n" 618 " [,driver specific parameters...]\n" 619 " configure a block backend\n", QEMU_ARCH_ALL) 620STEXI 621@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]] 622@findex -blockdev 623 624Define a new block driver node. Some of the options apply to all block drivers, 625other options are only accepted for a specific block driver. See below for a 626list of generic options and options for the most common block drivers. 627 628Options that expect a reference to another node (e.g. @code{file}) can be 629given in two ways. Either you specify the node name of an already existing node 630(file=@var{node-name}), or you define a new node inline, adding options 631for the referenced node after a dot (file.filename=@var{path},file.aio=native). 632 633A block driver node created with @option{-blockdev} can be used for a guest 634device by specifying its node name for the @code{drive} property in a 635@option{-device} argument that defines a block device. 636 637@table @option 638@item Valid options for any block driver node: 639 640@table @code 641@item driver 642Specifies the block driver to use for the given node. 643@item node-name 644This defines the name of the block driver node by which it will be referenced 645later. The name must be unique, i.e. it must not match the name of a different 646block driver node, or (if you use @option{-drive} as well) the ID of a drive. 647 648If no node name is specified, it is automatically generated. The generated node 649name is not intended to be predictable and changes between QEMU invocations. 650For the top level, an explicit node name must be specified. 651@item read-only 652Open the node read-only. Guest write attempts will fail. 653@item cache.direct 654The host page cache can be avoided with @option{cache.direct=on}. This will 655attempt to do disk IO directly to the guest's memory. QEMU may still perform an 656internal copy of the data. 657@item cache.no-flush 658In case you don't care about data integrity over host failures, you can use 659@option{cache.no-flush=on}. This option tells QEMU that it never needs to write 660any data to the disk but can instead keep things in cache. If anything goes 661wrong, like your host losing power, the disk storage getting disconnected 662accidentally, etc. your image will most probably be rendered unusable. 663@item discard=@var{discard} 664@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls 665whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are 666ignored or passed to the filesystem. Some machine types may not support 667discard requests. 668@item detect-zeroes=@var{detect-zeroes} 669@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 670conversion of plain zero writes by the OS to driver specific optimized 671zero write commands. You may even choose "unmap" if @var{discard} is set 672to "unmap" to allow a zero write to be converted to an @code{unmap} operation. 673@end table 674 675@item Driver-specific options for @code{file} 676 677This is the protocol-level block driver for accessing regular files. 678 679@table @code 680@item filename 681The path to the image file in the local filesystem 682@item aio 683Specifies the AIO backend (threads/native, default: threads) 684@item locking 685Specifies whether the image file is protected with Linux OFD / POSIX locks. The 686default is to use the Linux Open File Descriptor API if available, otherwise no 687lock is applied. (auto/on/off, default: auto) 688@end table 689Example: 690@example 691-blockdev driver=file,node-name=disk,filename=disk.img 692@end example 693 694@item Driver-specific options for @code{raw} 695 696This is the image format block driver for raw images. It is usually 697stacked on top of a protocol level block driver such as @code{file}. 698 699@table @code 700@item file 701Reference to or definition of the data source block driver node 702(e.g. a @code{file} driver node) 703@end table 704Example 1: 705@example 706-blockdev driver=file,node-name=disk_file,filename=disk.img 707-blockdev driver=raw,node-name=disk,file=disk_file 708@end example 709Example 2: 710@example 711-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img 712@end example 713 714@item Driver-specific options for @code{qcow2} 715 716This is the image format block driver for qcow2 images. It is usually 717stacked on top of a protocol level block driver such as @code{file}. 718 719@table @code 720@item file 721Reference to or definition of the data source block driver node 722(e.g. a @code{file} driver node) 723 724@item backing 725Reference to or definition of the backing file block device (default is taken 726from the image file). It is allowed to pass @code{null} here in order to disable 727the default backing file. 728 729@item lazy-refcounts 730Whether to enable the lazy refcounts feature (on/off; default is taken from the 731image file) 732 733@item cache-size 734The maximum total size of the L2 table and refcount block caches in bytes 735(default: the sum of l2-cache-size and refcount-cache-size) 736 737@item l2-cache-size 738The maximum size of the L2 table cache in bytes 739(default: if cache-size is not specified - 32M on Linux platforms, and 8M on 740non-Linux platforms; otherwise, as large as possible within the cache-size, 741while permitting the requested or the minimal refcount cache size) 742 743@item refcount-cache-size 744The maximum size of the refcount block cache in bytes 745(default: 4 times the cluster size; or if cache-size is specified, the part of 746it which is not used for the L2 cache) 747 748@item cache-clean-interval 749Clean unused entries in the L2 and refcount caches. The interval is in seconds. 750The default value is 600 on supporting platforms, and 0 on other platforms. 751Setting it to 0 disables this feature. 752 753@item pass-discard-request 754Whether discard requests to the qcow2 device should be forwarded to the data 755source (on/off; default: on if discard=unmap is specified, off otherwise) 756 757@item pass-discard-snapshot 758Whether discard requests for the data source should be issued when a snapshot 759operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off; 760default: on) 761 762@item pass-discard-other 763Whether discard requests for the data source should be issued on other 764occasions where a cluster gets freed (on/off; default: off) 765 766@item overlap-check 767Which overlap checks to perform for writes to the image 768(none/constant/cached/all; default: cached). For details or finer 769granularity control refer to the QAPI documentation of @code{blockdev-add}. 770@end table 771 772Example 1: 773@example 774-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2 775-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216 776@end example 777Example 2: 778@example 779-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2 780@end example 781 782@item Driver-specific options for other drivers 783Please refer to the QAPI documentation of the @code{blockdev-add} QMP command. 784 785@end table 786 787ETEXI 788 789DEF("drive", HAS_ARG, QEMU_OPTION_drive, 790 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 791 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 792 " [,snapshot=on|off][,rerror=ignore|stop|report]\n" 793 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 794 " [,readonly=on|off][,copy-on-read=on|off]\n" 795 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 796 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 797 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 798 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 799 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 800 " [[,iops_size=is]]\n" 801 " [[,group=g]]\n" 802 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 803STEXI 804@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 805@findex -drive 806 807Define a new drive. This includes creating a block driver node (the backend) as 808well as a guest device, and is mostly a shortcut for defining the corresponding 809@option{-blockdev} and @option{-device} options. 810 811@option{-drive} accepts all options that are accepted by @option{-blockdev}. In 812addition, it knows the following options: 813 814@table @option 815@item file=@var{file} 816This option defines which disk image (@pxref{disk_images}) to use with 817this drive. If the filename contains comma, you must double it 818(for instance, "file=my,,file" to use file "my,file"). 819 820Special files such as iSCSI devices can be specified using protocol 821specific URLs. See the section for "Device URL Syntax" for more information. 822@item if=@var{interface} 823This option defines on which type on interface the drive is connected. 824Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none. 825@item bus=@var{bus},unit=@var{unit} 826These options define where is connected the drive by defining the bus number and 827the unit id. 828@item index=@var{index} 829This option defines where is connected the drive by using an index in the list 830of available connectors of a given interface type. 831@item media=@var{media} 832This option defines the type of the media: disk or cdrom. 833@item snapshot=@var{snapshot} 834@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 835(see @option{-snapshot}). 836@item cache=@var{cache} 837@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" 838and controls how the host cache is used to access block data. This is a 839shortcut that sets the @option{cache.direct} and @option{cache.no-flush} 840options (as in @option{-blockdev}), and additionally @option{cache.writeback}, 841which provides a default for the @option{write-cache} option of block guest 842devices (as in @option{-device}). The modes correspond to the following 843settings: 844 845@c Our texi2pod.pl script doesn't support @multitable, so fall back to using 846@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage 847@c and the HTML output. 848@example 849@ │ cache.writeback cache.direct cache.no-flush 850─────────────┼───────────────────────────────────────────────── 851writeback │ on off off 852none │ on on off 853writethrough │ off off off 854directsync │ off on off 855unsafe │ on off on 856@end example 857 858The default mode is @option{cache=writeback}. 859 860@item aio=@var{aio} 861@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 862@item format=@var{format} 863Specify which disk @var{format} will be used rather than detecting 864the format. Can be used to specify format=raw to avoid interpreting 865an untrusted format header. 866@item werror=@var{action},rerror=@var{action} 867Specify which @var{action} to take on write and read errors. Valid actions are: 868"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 869"report" (report the error to the guest), "enospc" (pause QEMU only if the 870host disk is full; report the error to the guest otherwise). 871The default setting is @option{werror=enospc} and @option{rerror=report}. 872@item copy-on-read=@var{copy-on-read} 873@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 874file sectors into the image file. 875@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w} 876Specify bandwidth throttling limits in bytes per second, either for all request 877types or for reads or writes only. Small values can lead to timeouts or hangs 878inside the guest. A safe minimum for disks is 2 MB/s. 879@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm} 880Specify bursts in bytes per second, either for all request types or for reads 881or writes only. Bursts allow the guest I/O to spike above the limit 882temporarily. 883@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w} 884Specify request rate limits in requests per second, either for all request 885types or for reads or writes only. 886@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm} 887Specify bursts in requests per second, either for all request types or for reads 888or writes only. Bursts allow the guest I/O to spike above the limit 889temporarily. 890@item iops_size=@var{is} 891Let every @var{is} bytes of a request count as a new request for iops 892throttling purposes. Use this option to prevent guests from circumventing iops 893limits by sending fewer but larger requests. 894@item group=@var{g} 895Join a throttling quota group with given name @var{g}. All drives that are 896members of the same group are accounted for together. Use this option to 897prevent guests from circumventing throttling limits by using many small disks 898instead of a single larger disk. 899@end table 900 901By default, the @option{cache.writeback=on} mode is used. It will report data 902writes as completed as soon as the data is present in the host page cache. 903This is safe as long as your guest OS makes sure to correctly flush disk caches 904where needed. If your guest OS does not handle volatile disk write caches 905correctly and your host crashes or loses power, then the guest may experience 906data corruption. 907 908For such guests, you should consider using @option{cache.writeback=off}. This 909means that the host page cache will be used to read and write data, but write 910notification will be sent to the guest only after QEMU has made sure to flush 911each write to the disk. Be aware that this has a major impact on performance. 912 913When using the @option{-snapshot} option, unsafe caching is always used. 914 915Copy-on-read avoids accessing the same backing file sectors repeatedly and is 916useful when the backing file is over a slow network. By default copy-on-read 917is off. 918 919Instead of @option{-cdrom} you can use: 920@example 921qemu-system-i386 -drive file=file,index=2,media=cdrom 922@end example 923 924Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 925use: 926@example 927qemu-system-i386 -drive file=file,index=0,media=disk 928qemu-system-i386 -drive file=file,index=1,media=disk 929qemu-system-i386 -drive file=file,index=2,media=disk 930qemu-system-i386 -drive file=file,index=3,media=disk 931@end example 932 933You can open an image using pre-opened file descriptors from an fd set: 934@example 935qemu-system-i386 936-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 937-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 938-drive file=/dev/fdset/2,index=0,media=disk 939@end example 940 941You can connect a CDROM to the slave of ide0: 942@example 943qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 944@end example 945 946If you don't specify the "file=" argument, you define an empty drive: 947@example 948qemu-system-i386 -drive if=ide,index=1,media=cdrom 949@end example 950 951Instead of @option{-fda}, @option{-fdb}, you can use: 952@example 953qemu-system-i386 -drive file=file,index=0,if=floppy 954qemu-system-i386 -drive file=file,index=1,if=floppy 955@end example 956 957By default, @var{interface} is "ide" and @var{index} is automatically 958incremented: 959@example 960qemu-system-i386 -drive file=a -drive file=b" 961@end example 962is interpreted like: 963@example 964qemu-system-i386 -hda a -hdb b 965@end example 966ETEXI 967 968DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 969 "-mtdblock file use 'file' as on-board Flash memory image\n", 970 QEMU_ARCH_ALL) 971STEXI 972@item -mtdblock @var{file} 973@findex -mtdblock 974Use @var{file} as on-board Flash memory image. 975ETEXI 976 977DEF("sd", HAS_ARG, QEMU_OPTION_sd, 978 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 979STEXI 980@item -sd @var{file} 981@findex -sd 982Use @var{file} as SecureDigital card image. 983ETEXI 984 985DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 986 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 987STEXI 988@item -pflash @var{file} 989@findex -pflash 990Use @var{file} as a parallel flash image. 991ETEXI 992 993DEF("snapshot", 0, QEMU_OPTION_snapshot, 994 "-snapshot write to temporary files instead of disk image files\n", 995 QEMU_ARCH_ALL) 996STEXI 997@item -snapshot 998@findex -snapshot 999Write to temporary files instead of disk image files. In this case, 1000the raw disk image you use is not written back. You can however force 1001the write back by pressing @key{C-a s} (@pxref{disk_images}). 1002ETEXI 1003 1004DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 1005 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 1006 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n" 1007 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n" 1008 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n" 1009 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n" 1010 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n" 1011 " [[,throttling.iops-size=is]]\n", 1012 QEMU_ARCH_ALL) 1013 1014STEXI 1015 1016@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}] 1017@findex -fsdev 1018Define a new file system device. Valid options are: 1019@table @option 1020@item @var{fsdriver} 1021This option specifies the fs driver backend to use. 1022Currently "local", "handle" and "proxy" file system drivers are supported. 1023@item id=@var{id} 1024Specifies identifier for this device 1025@item path=@var{path} 1026Specifies the export path for the file system device. Files under 1027this path will be available to the 9p client on the guest. 1028@item security_model=@var{security_model} 1029Specifies the security model to be used for this export path. 1030Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1031In "passthrough" security model, files are stored using the same 1032credentials as they are created on the guest. This requires QEMU 1033to run as root. In "mapped-xattr" security model, some of the file 1034attributes like uid, gid, mode bits and link target are stored as 1035file attributes. For "mapped-file" these attributes are stored in the 1036hidden .virtfs_metadata directory. Directories exported by this security model cannot 1037interact with other unix tools. "none" security model is same as 1038passthrough except the sever won't report failures if it fails to 1039set file attributes like ownership. Security model is mandatory 1040only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 1041security model as a parameter. 1042@item writeout=@var{writeout} 1043This is an optional argument. The only supported value is "immediate". 1044This means that host page cache will be used to read and write data but 1045write notification will be sent to the guest only when the data has been 1046reported as written by the storage subsystem. 1047@item readonly 1048Enables exporting 9p share as a readonly mount for guests. By default 1049read-write access is given. 1050@item socket=@var{socket} 1051Enables proxy filesystem driver to use passed socket file for communicating 1052with virtfs-proxy-helper 1053@item sock_fd=@var{sock_fd} 1054Enables proxy filesystem driver to use passed socket descriptor for 1055communicating with virtfs-proxy-helper. Usually a helper like libvirt 1056will create socketpair and pass one of the fds as sock_fd 1057@item fmode=@var{fmode} 1058Specifies the default mode for newly created files on the host. Works only 1059with security models "mapped-xattr" and "mapped-file". 1060@item dmode=@var{dmode} 1061Specifies the default mode for newly created directories on the host. Works 1062only with security models "mapped-xattr" and "mapped-file". 1063@end table 1064 1065-fsdev option is used along with -device driver "virtio-9p-pci". 1066@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 1067Options for virtio-9p-pci driver are: 1068@table @option 1069@item fsdev=@var{id} 1070Specifies the id value specified along with -fsdev option 1071@item mount_tag=@var{mount_tag} 1072Specifies the tag name to be used by the guest to mount this export point 1073@end table 1074 1075ETEXI 1076 1077DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 1078 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 1079 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n", 1080 QEMU_ARCH_ALL) 1081 1082STEXI 1083 1084@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}] 1085@findex -virtfs 1086 1087The general form of a Virtual File system pass-through options are: 1088@table @option 1089@item @var{fsdriver} 1090This option specifies the fs driver backend to use. 1091Currently "local", "handle" and "proxy" file system drivers are supported. 1092@item id=@var{id} 1093Specifies identifier for this device 1094@item path=@var{path} 1095Specifies the export path for the file system device. Files under 1096this path will be available to the 9p client on the guest. 1097@item security_model=@var{security_model} 1098Specifies the security model to be used for this export path. 1099Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1100In "passthrough" security model, files are stored using the same 1101credentials as they are created on the guest. This requires QEMU 1102to run as root. In "mapped-xattr" security model, some of the file 1103attributes like uid, gid, mode bits and link target are stored as 1104file attributes. For "mapped-file" these attributes are stored in the 1105hidden .virtfs_metadata directory. Directories exported by this security model cannot 1106interact with other unix tools. "none" security model is same as 1107passthrough except the sever won't report failures if it fails to 1108set file attributes like ownership. Security model is mandatory only 1109for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 1110model as a parameter. 1111@item writeout=@var{writeout} 1112This is an optional argument. The only supported value is "immediate". 1113This means that host page cache will be used to read and write data but 1114write notification will be sent to the guest only when the data has been 1115reported as written by the storage subsystem. 1116@item readonly 1117Enables exporting 9p share as a readonly mount for guests. By default 1118read-write access is given. 1119@item socket=@var{socket} 1120Enables proxy filesystem driver to use passed socket file for 1121communicating with virtfs-proxy-helper. Usually a helper like libvirt 1122will create socketpair and pass one of the fds as sock_fd 1123@item sock_fd 1124Enables proxy filesystem driver to use passed 'sock_fd' as the socket 1125descriptor for interfacing with virtfs-proxy-helper 1126@item fmode=@var{fmode} 1127Specifies the default mode for newly created files on the host. Works only 1128with security models "mapped-xattr" and "mapped-file". 1129@item dmode=@var{dmode} 1130Specifies the default mode for newly created directories on the host. Works 1131only with security models "mapped-xattr" and "mapped-file". 1132@end table 1133ETEXI 1134 1135DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 1136 "-virtfs_synth Create synthetic file system image\n", 1137 QEMU_ARCH_ALL) 1138STEXI 1139@item -virtfs_synth 1140@findex -virtfs_synth 1141Create synthetic file system image 1142ETEXI 1143 1144DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 1145 "-iscsi [user=user][,password=password]\n" 1146 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 1147 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 1148 " [,timeout=timeout]\n" 1149 " iSCSI session parameters\n", QEMU_ARCH_ALL) 1150 1151STEXI 1152@item -iscsi 1153@findex -iscsi 1154Configure iSCSI session parameters. 1155ETEXI 1156 1157STEXI 1158@end table 1159ETEXI 1160DEFHEADING() 1161 1162DEFHEADING(USB options:) 1163STEXI 1164@table @option 1165ETEXI 1166 1167DEF("usb", 0, QEMU_OPTION_usb, 1168 "-usb enable the USB driver (if it is not used by default yet)\n", 1169 QEMU_ARCH_ALL) 1170STEXI 1171@item -usb 1172@findex -usb 1173Enable the USB driver (if it is not used by default yet). 1174ETEXI 1175 1176DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 1177 "-usbdevice name add the host or guest USB device 'name'\n", 1178 QEMU_ARCH_ALL) 1179STEXI 1180 1181@item -usbdevice @var{devname} 1182@findex -usbdevice 1183Add the USB device @var{devname}. Note that this option is deprecated, 1184please use @code{-device usb-...} instead. @xref{usb_devices}. 1185 1186@table @option 1187 1188@item mouse 1189Virtual Mouse. This will override the PS/2 mouse emulation when activated. 1190 1191@item tablet 1192Pointer device that uses absolute coordinates (like a touchscreen). This 1193means QEMU is able to report the mouse position without having to grab the 1194mouse. Also overrides the PS/2 mouse emulation when activated. 1195 1196@item braille 1197Braille device. This will use BrlAPI to display the braille output on a real 1198or fake device. 1199 1200@end table 1201ETEXI 1202 1203STEXI 1204@end table 1205ETEXI 1206DEFHEADING() 1207 1208DEFHEADING(Display options:) 1209STEXI 1210@table @option 1211ETEXI 1212 1213DEF("display", HAS_ARG, QEMU_OPTION_display, 1214 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 1215 " [,window_close=on|off][,gl=on|core|es|off]\n" 1216 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 1217 "-display vnc=<display>[,<optargs>]\n" 1218 "-display curses\n" 1219 "-display none" 1220 " select display type\n" 1221 "The default display is equivalent to\n" 1222#if defined(CONFIG_GTK) 1223 "\t\"-display gtk\"\n" 1224#elif defined(CONFIG_SDL) 1225 "\t\"-display sdl\"\n" 1226#elif defined(CONFIG_COCOA) 1227 "\t\"-display cocoa\"\n" 1228#elif defined(CONFIG_VNC) 1229 "\t\"-vnc localhost:0,to=99,id=default\"\n" 1230#else 1231 "\t\"-display none\"\n" 1232#endif 1233 , QEMU_ARCH_ALL) 1234STEXI 1235@item -display @var{type} 1236@findex -display 1237Select type of display to use. This option is a replacement for the 1238old style -sdl/-curses/... options. Valid values for @var{type} are 1239@table @option 1240@item sdl 1241Display video output via SDL (usually in a separate graphics 1242window; see the SDL documentation for other possibilities). 1243@item curses 1244Display video output via curses. For graphics device models which 1245support a text mode, QEMU can display this output using a 1246curses/ncurses interface. Nothing is displayed when the graphics 1247device is in graphical mode or if the graphics device does not support 1248a text mode. Generally only the VGA device models support text mode. 1249@item none 1250Do not display video output. The guest will still see an emulated 1251graphics card, but its output will not be displayed to the QEMU 1252user. This option differs from the -nographic option in that it 1253only affects what is done with video output; -nographic also changes 1254the destination of the serial and parallel port data. 1255@item gtk 1256Display video output in a GTK window. This interface provides drop-down 1257menus and other UI elements to configure and control the VM during 1258runtime. 1259@item vnc 1260Start a VNC server on display <arg> 1261@end table 1262ETEXI 1263 1264DEF("nographic", 0, QEMU_OPTION_nographic, 1265 "-nographic disable graphical output and redirect serial I/Os to console\n", 1266 QEMU_ARCH_ALL) 1267STEXI 1268@item -nographic 1269@findex -nographic 1270Normally, if QEMU is compiled with graphical window support, it displays 1271output such as guest graphics, guest console, and the QEMU monitor in a 1272window. With this option, you can totally disable graphical output so 1273that QEMU is a simple command line application. The emulated serial port 1274is redirected on the console and muxed with the monitor (unless 1275redirected elsewhere explicitly). Therefore, you can still use QEMU to 1276debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1277switching between the console and monitor. 1278ETEXI 1279 1280DEF("curses", 0, QEMU_OPTION_curses, 1281 "-curses shorthand for -display curses\n", 1282 QEMU_ARCH_ALL) 1283STEXI 1284@item -curses 1285@findex -curses 1286Normally, if QEMU is compiled with graphical window support, it displays 1287output such as guest graphics, guest console, and the QEMU monitor in a 1288window. With this option, QEMU can display the VGA output when in text 1289mode using a curses/ncurses interface. Nothing is displayed in graphical 1290mode. 1291ETEXI 1292 1293DEF("no-frame", 0, QEMU_OPTION_no_frame, 1294 "-no-frame open SDL window without a frame and window decorations\n", 1295 QEMU_ARCH_ALL) 1296STEXI 1297@item -no-frame 1298@findex -no-frame 1299Do not use decorations for SDL windows and start them using the whole 1300available screen space. This makes the using QEMU in a dedicated desktop 1301workspace more convenient. 1302ETEXI 1303 1304DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1305 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1306 QEMU_ARCH_ALL) 1307STEXI 1308@item -alt-grab 1309@findex -alt-grab 1310Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1311affects the special keys (for fullscreen, monitor-mode switching, etc). 1312ETEXI 1313 1314DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1315 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1316 QEMU_ARCH_ALL) 1317STEXI 1318@item -ctrl-grab 1319@findex -ctrl-grab 1320Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1321affects the special keys (for fullscreen, monitor-mode switching, etc). 1322ETEXI 1323 1324DEF("no-quit", 0, QEMU_OPTION_no_quit, 1325 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1326STEXI 1327@item -no-quit 1328@findex -no-quit 1329Disable SDL window close capability. 1330ETEXI 1331 1332DEF("sdl", 0, QEMU_OPTION_sdl, 1333 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1334STEXI 1335@item -sdl 1336@findex -sdl 1337Enable SDL. 1338ETEXI 1339 1340DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1341 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1342 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1343 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1344 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1345 " [,tls-ciphers=<list>]\n" 1346 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1347 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1348 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1349 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1350 " [,jpeg-wan-compression=[auto|never|always]]\n" 1351 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1352 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1353 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1354 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1355 " [,gl=[on|off]][,rendernode=<file>]\n" 1356 " enable spice\n" 1357 " at least one of {port, tls-port} is mandatory\n", 1358 QEMU_ARCH_ALL) 1359STEXI 1360@item -spice @var{option}[,@var{option}[,...]] 1361@findex -spice 1362Enable the spice remote desktop protocol. Valid options are 1363 1364@table @option 1365 1366@item port=<nr> 1367Set the TCP port spice is listening on for plaintext channels. 1368 1369@item addr=<addr> 1370Set the IP address spice is listening on. Default is any address. 1371 1372@item ipv4 1373@itemx ipv6 1374@itemx unix 1375Force using the specified IP version. 1376 1377@item password=<secret> 1378Set the password you need to authenticate. 1379 1380@item sasl 1381Require that the client use SASL to authenticate with the spice. 1382The exact choice of authentication method used is controlled from the 1383system / user's SASL configuration file for the 'qemu' service. This 1384is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1385unprivileged user, an environment variable SASL_CONF_PATH can be used 1386to make it search alternate locations for the service config. 1387While some SASL auth methods can also provide data encryption (eg GSSAPI), 1388it is recommended that SASL always be combined with the 'tls' and 1389'x509' settings to enable use of SSL and server certificates. This 1390ensures a data encryption preventing compromise of authentication 1391credentials. 1392 1393@item disable-ticketing 1394Allow client connects without authentication. 1395 1396@item disable-copy-paste 1397Disable copy paste between the client and the guest. 1398 1399@item disable-agent-file-xfer 1400Disable spice-vdagent based file-xfer between the client and the guest. 1401 1402@item tls-port=<nr> 1403Set the TCP port spice is listening on for encrypted channels. 1404 1405@item x509-dir=<dir> 1406Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1407 1408@item x509-key-file=<file> 1409@itemx x509-key-password=<file> 1410@itemx x509-cert-file=<file> 1411@itemx x509-cacert-file=<file> 1412@itemx x509-dh-key-file=<file> 1413The x509 file names can also be configured individually. 1414 1415@item tls-ciphers=<list> 1416Specify which ciphers to use. 1417 1418@item tls-channel=[main|display|cursor|inputs|record|playback] 1419@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1420Force specific channel to be used with or without TLS encryption. The 1421options can be specified multiple times to configure multiple 1422channels. The special name "default" can be used to set the default 1423mode. For channels which are not explicitly forced into one mode the 1424spice client is allowed to pick tls/plaintext as he pleases. 1425 1426@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1427Configure image compression (lossless). 1428Default is auto_glz. 1429 1430@item jpeg-wan-compression=[auto|never|always] 1431@itemx zlib-glz-wan-compression=[auto|never|always] 1432Configure wan image compression (lossy for slow links). 1433Default is auto. 1434 1435@item streaming-video=[off|all|filter] 1436Configure video stream detection. Default is off. 1437 1438@item agent-mouse=[on|off] 1439Enable/disable passing mouse events via vdagent. Default is on. 1440 1441@item playback-compression=[on|off] 1442Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1443 1444@item seamless-migration=[on|off] 1445Enable/disable spice seamless migration. Default is off. 1446 1447@item gl=[on|off] 1448Enable/disable OpenGL context. Default is off. 1449 1450@item rendernode=<file> 1451DRM render node for OpenGL rendering. If not specified, it will pick 1452the first available. (Since 2.9) 1453 1454@end table 1455ETEXI 1456 1457DEF("portrait", 0, QEMU_OPTION_portrait, 1458 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1459 QEMU_ARCH_ALL) 1460STEXI 1461@item -portrait 1462@findex -portrait 1463Rotate graphical output 90 deg left (only PXA LCD). 1464ETEXI 1465 1466DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1467 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1468 QEMU_ARCH_ALL) 1469STEXI 1470@item -rotate @var{deg} 1471@findex -rotate 1472Rotate graphical output some deg left (only PXA LCD). 1473ETEXI 1474 1475DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1476 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1477 " select video card type\n", QEMU_ARCH_ALL) 1478STEXI 1479@item -vga @var{type} 1480@findex -vga 1481Select type of VGA card to emulate. Valid values for @var{type} are 1482@table @option 1483@item cirrus 1484Cirrus Logic GD5446 Video card. All Windows versions starting from 1485Windows 95 should recognize and use this graphic card. For optimal 1486performances, use 16 bit color depth in the guest and the host OS. 1487(This card was the default before QEMU 2.2) 1488@item std 1489Standard VGA card with Bochs VBE extensions. If your guest OS 1490supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1491to use high resolution modes (>= 1280x1024x16) then you should use 1492this option. (This card is the default since QEMU 2.2) 1493@item vmware 1494VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1495recent XFree86/XOrg server or Windows guest with a driver for this 1496card. 1497@item qxl 1498QXL paravirtual graphic card. It is VGA compatible (including VESA 14992.0 VBE support). Works best with qxl guest drivers installed though. 1500Recommended choice when using the spice protocol. 1501@item tcx 1502(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1503sun4m machines and offers both 8-bit and 24-bit colour depths at a 1504fixed resolution of 1024x768. 1505@item cg3 1506(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1507for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1508resolutions aimed at people wishing to run older Solaris versions. 1509@item virtio 1510Virtio VGA card. 1511@item none 1512Disable VGA card. 1513@end table 1514ETEXI 1515 1516DEF("full-screen", 0, QEMU_OPTION_full_screen, 1517 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1518STEXI 1519@item -full-screen 1520@findex -full-screen 1521Start in full screen. 1522ETEXI 1523 1524DEF("g", 1, QEMU_OPTION_g , 1525 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1526 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1527STEXI 1528@item -g @var{width}x@var{height}[x@var{depth}] 1529@findex -g 1530Set the initial graphical resolution and depth (PPC, SPARC only). 1531ETEXI 1532 1533DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1534 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1535STEXI 1536@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1537@findex -vnc 1538Normally, if QEMU is compiled with graphical window support, it displays 1539output such as guest graphics, guest console, and the QEMU monitor in a 1540window. With this option, you can have QEMU listen on VNC display 1541@var{display} and redirect the VGA display over the VNC session. It is 1542very useful to enable the usb tablet device when using this option 1543(option @option{-device usb-tablet}). When using the VNC display, you 1544must use the @option{-k} parameter to set the keyboard layout if you are 1545not using en-us. Valid syntax for the @var{display} is 1546 1547@table @option 1548 1549@item to=@var{L} 1550 1551With this option, QEMU will try next available VNC @var{display}s, until the 1552number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1553available, e.g. port 5900+@var{display} is already used by another 1554application. By default, to=0. 1555 1556@item @var{host}:@var{d} 1557 1558TCP connections will only be allowed from @var{host} on display @var{d}. 1559By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1560be omitted in which case the server will accept connections from any host. 1561 1562@item unix:@var{path} 1563 1564Connections will be allowed over UNIX domain sockets where @var{path} is the 1565location of a unix socket to listen for connections on. 1566 1567@item none 1568 1569VNC is initialized but not started. The monitor @code{change} command 1570can be used to later start the VNC server. 1571 1572@end table 1573 1574Following the @var{display} value there may be one or more @var{option} flags 1575separated by commas. Valid options are 1576 1577@table @option 1578 1579@item reverse 1580 1581Connect to a listening VNC client via a ``reverse'' connection. The 1582client is specified by the @var{display}. For reverse network 1583connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1584is a TCP port number, not a display number. 1585 1586@item websocket 1587 1588Opens an additional TCP listening port dedicated to VNC Websocket connections. 1589If a bare @var{websocket} option is given, the Websocket port is 15905700+@var{display}. An alternative port can be specified with the 1591syntax @code{websocket}=@var{port}. 1592 1593If @var{host} is specified connections will only be allowed from this host. 1594It is possible to control the websocket listen address independently, using 1595the syntax @code{websocket}=@var{host}:@var{port}. 1596 1597If no TLS credentials are provided, the websocket connection runs in 1598unencrypted mode. If TLS credentials are provided, the websocket connection 1599requires encrypted client connections. 1600 1601@item password 1602 1603Require that password based authentication is used for client connections. 1604 1605The password must be set separately using the @code{set_password} command in 1606the @ref{pcsys_monitor}. The syntax to change your password is: 1607@code{set_password <protocol> <password>} where <protocol> could be either 1608"vnc" or "spice". 1609 1610If you would like to change <protocol> password expiration, you should use 1611@code{expire_password <protocol> <expiration-time>} where expiration time could 1612be one of the following options: now, never, +seconds or UNIX time of 1613expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1614to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1615date and time). 1616 1617You can also use keywords "now" or "never" for the expiration time to 1618allow <protocol> password to expire immediately or never expire. 1619 1620@item tls-creds=@var{ID} 1621 1622Provides the ID of a set of TLS credentials to use to secure the 1623VNC server. They will apply to both the normal VNC server socket 1624and the websocket socket (if enabled). Setting TLS credentials 1625will cause the VNC server socket to enable the VeNCrypt auth 1626mechanism. The credentials should have been previously created 1627using the @option{-object tls-creds} argument. 1628 1629@item sasl 1630 1631Require that the client use SASL to authenticate with the VNC server. 1632The exact choice of authentication method used is controlled from the 1633system / user's SASL configuration file for the 'qemu' service. This 1634is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1635unprivileged user, an environment variable SASL_CONF_PATH can be used 1636to make it search alternate locations for the service config. 1637While some SASL auth methods can also provide data encryption (eg GSSAPI), 1638it is recommended that SASL always be combined with the 'tls' and 1639'x509' settings to enable use of SSL and server certificates. This 1640ensures a data encryption preventing compromise of authentication 1641credentials. See the @ref{vnc_security} section for details on using 1642SASL authentication. 1643 1644@item acl 1645 1646Turn on access control lists for checking of the x509 client certificate 1647and SASL party. For x509 certs, the ACL check is made against the 1648certificate's distinguished name. This is something that looks like 1649@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1650made against the username, which depending on the SASL plugin, may 1651include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1652When the @option{acl} flag is set, the initial access list will be 1653empty, with a @code{deny} policy. Thus no one will be allowed to 1654use the VNC server until the ACLs have been loaded. This can be 1655achieved using the @code{acl} monitor command. 1656 1657@item lossy 1658 1659Enable lossy compression methods (gradient, JPEG, ...). If this 1660option is set, VNC client may receive lossy framebuffer updates 1661depending on its encoding settings. Enabling this option can save 1662a lot of bandwidth at the expense of quality. 1663 1664@item non-adaptive 1665 1666Disable adaptive encodings. Adaptive encodings are enabled by default. 1667An adaptive encoding will try to detect frequently updated screen regions, 1668and send updates in these regions using a lossy encoding (like JPEG). 1669This can be really helpful to save bandwidth when playing videos. Disabling 1670adaptive encodings restores the original static behavior of encodings 1671like Tight. 1672 1673@item share=[allow-exclusive|force-shared|ignore] 1674 1675Set display sharing policy. 'allow-exclusive' allows clients to ask 1676for exclusive access. As suggested by the rfb spec this is 1677implemented by dropping other connections. Connecting multiple 1678clients in parallel requires all clients asking for a shared session 1679(vncviewer: -shared switch). This is the default. 'force-shared' 1680disables exclusive client access. Useful for shared desktop sessions, 1681where you don't want someone forgetting specify -shared disconnect 1682everybody else. 'ignore' completely ignores the shared flag and 1683allows everybody connect unconditionally. Doesn't conform to the rfb 1684spec but is traditional QEMU behavior. 1685 1686@item key-delay-ms 1687 1688Set keyboard delay, for key down and key up events, in milliseconds. 1689Default is 10. Keyboards are low-bandwidth devices, so this slowdown 1690can help the device and guest to keep up and not lose events in case 1691events are arriving in bulk. Possible causes for the latter are flaky 1692network connections, or scripts for automated testing. 1693 1694@end table 1695ETEXI 1696 1697STEXI 1698@end table 1699ETEXI 1700ARCHHEADING(, QEMU_ARCH_I386) 1701 1702ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1703STEXI 1704@table @option 1705ETEXI 1706 1707DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1708 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1709 QEMU_ARCH_I386) 1710STEXI 1711@item -win2k-hack 1712@findex -win2k-hack 1713Use it when installing Windows 2000 to avoid a disk full bug. After 1714Windows 2000 is installed, you no longer need this option (this option 1715slows down the IDE transfers). 1716ETEXI 1717 1718DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1719 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1720 QEMU_ARCH_I386) 1721STEXI 1722@item -no-fd-bootchk 1723@findex -no-fd-bootchk 1724Disable boot signature checking for floppy disks in BIOS. May 1725be needed to boot from old floppy disks. 1726ETEXI 1727 1728DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1729 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1730STEXI 1731@item -no-acpi 1732@findex -no-acpi 1733Disable ACPI (Advanced Configuration and Power Interface) support. Use 1734it if your guest OS complains about ACPI problems (PC target machine 1735only). 1736ETEXI 1737 1738DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1739 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1740STEXI 1741@item -no-hpet 1742@findex -no-hpet 1743Disable HPET support. 1744ETEXI 1745 1746DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1747 "-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" 1748 " ACPI table description\n", QEMU_ARCH_I386) 1749STEXI 1750@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}]...] 1751@findex -acpitable 1752Add ACPI table with specified header fields and context from specified files. 1753For file=, take whole ACPI table from the specified files, including all 1754ACPI headers (possible overridden by other options). 1755For data=, only data 1756portion of the table is used, all header information is specified in the 1757command line. 1758If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1759fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1760to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1761spec. 1762ETEXI 1763 1764DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1765 "-smbios file=binary\n" 1766 " load SMBIOS entry from binary file\n" 1767 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1768 " [,uefi=on|off]\n" 1769 " specify SMBIOS type 0 fields\n" 1770 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1771 " [,uuid=uuid][,sku=str][,family=str]\n" 1772 " specify SMBIOS type 1 fields\n" 1773 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1774 " [,asset=str][,location=str]\n" 1775 " specify SMBIOS type 2 fields\n" 1776 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1777 " [,sku=str]\n" 1778 " specify SMBIOS type 3 fields\n" 1779 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1780 " [,asset=str][,part=str]\n" 1781 " specify SMBIOS type 4 fields\n" 1782 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1783 " [,asset=str][,part=str][,speed=%d]\n" 1784 " specify SMBIOS type 17 fields\n", 1785 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1786STEXI 1787@item -smbios file=@var{binary} 1788@findex -smbios 1789Load SMBIOS entry from binary file. 1790 1791@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1792Specify SMBIOS type 0 fields 1793 1794@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}] 1795Specify SMBIOS type 1 fields 1796 1797@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}] 1798Specify SMBIOS type 2 fields 1799 1800@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1801Specify SMBIOS type 3 fields 1802 1803@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1804Specify SMBIOS type 4 fields 1805 1806@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}] 1807Specify SMBIOS type 17 fields 1808ETEXI 1809 1810STEXI 1811@end table 1812ETEXI 1813DEFHEADING() 1814 1815DEFHEADING(Network options:) 1816STEXI 1817@table @option 1818ETEXI 1819 1820DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1821#ifdef CONFIG_SLIRP 1822 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 1823 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 1824 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1825 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n" 1826 " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1827#ifndef _WIN32 1828 "[,smb=dir[,smbserver=addr]]\n" 1829#endif 1830 " configure a user mode network backend with ID 'str',\n" 1831 " its DHCP server and optional services\n" 1832#endif 1833#ifdef _WIN32 1834 "-netdev tap,id=str,ifname=name\n" 1835 " configure a host TAP network backend with ID 'str'\n" 1836#else 1837 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1838 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1839 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1840 " [,poll-us=n]\n" 1841 " configure a host TAP network backend with ID 'str'\n" 1842 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1843 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1844 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1845 " to deconfigure it\n" 1846 " use '[down]script=no' to disable script execution\n" 1847 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1848 " configure it\n" 1849 " use 'fd=h' to connect to an already opened TAP interface\n" 1850 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1851 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1852 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1853 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1854 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1855 " use vhost=on to enable experimental in kernel accelerator\n" 1856 " (only has effect for virtio guests which use MSIX)\n" 1857 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1858 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1859 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1860 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1861 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 1862 " spent on busy polling for vhost net\n" 1863 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1864 " configure a host TAP network backend with ID 'str' that is\n" 1865 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1866 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1867#endif 1868#ifdef __linux__ 1869 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1870 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1871 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1872 " [,rxcookie=rxcookie][,offset=offset]\n" 1873 " configure a network backend with ID 'str' connected to\n" 1874 " an Ethernet over L2TPv3 pseudowire.\n" 1875 " Linux kernel 3.3+ as well as most routers can talk\n" 1876 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1877 " VM to a router and even VM to Host. It is a nearly-universal\n" 1878 " standard (RFC3391). Note - this implementation uses static\n" 1879 " pre-configured tunnels (same as the Linux kernel).\n" 1880 " use 'src=' to specify source address\n" 1881 " use 'dst=' to specify destination address\n" 1882 " use 'udp=on' to specify udp encapsulation\n" 1883 " use 'srcport=' to specify source udp port\n" 1884 " use 'dstport=' to specify destination udp port\n" 1885 " use 'ipv6=on' to force v6\n" 1886 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1887 " well as a weak security measure\n" 1888 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1889 " use 'txcookie=0x012345678' to specify a txcookie\n" 1890 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1891 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1892 " use 'pincounter=on' to work around broken counter handling in peer\n" 1893 " use 'offset=X' to add an extra offset between header and data\n" 1894#endif 1895 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1896 " configure a network backend to connect to another network\n" 1897 " using a socket connection\n" 1898 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1899 " configure a network backend to connect to a multicast maddr and port\n" 1900 " use 'localaddr=addr' to specify the host address to send packets from\n" 1901 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1902 " configure a network backend to connect to another network\n" 1903 " using an UDP tunnel\n" 1904#ifdef CONFIG_VDE 1905 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1906 " configure a network backend to connect to port 'n' of a vde switch\n" 1907 " running on host and listening for incoming connections on 'socketpath'.\n" 1908 " Use group 'groupname' and mode 'octalmode' to change default\n" 1909 " ownership and permissions for communication port.\n" 1910#endif 1911#ifdef CONFIG_NETMAP 1912 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1913 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1914 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1915 " netmap device, defaults to '/dev/netmap')\n" 1916#endif 1917#ifdef CONFIG_POSIX 1918 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 1919 " configure a vhost-user network, backed by a chardev 'dev'\n" 1920#endif 1921 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n" 1922 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL) 1923DEF("nic", HAS_ARG, QEMU_OPTION_nic, 1924 "-nic [tap|bridge|" 1925#ifdef CONFIG_SLIRP 1926 "user|" 1927#endif 1928#ifdef __linux__ 1929 "l2tpv3|" 1930#endif 1931#ifdef CONFIG_VDE 1932 "vde|" 1933#endif 1934#ifdef CONFIG_NETMAP 1935 "netmap|" 1936#endif 1937#ifdef CONFIG_POSIX 1938 "vhost-user|" 1939#endif 1940 "socket][,option][,...][mac=macaddr]\n" 1941 " initialize an on-board / default host NIC (using MAC address\n" 1942 " macaddr) and connect it to the given host network backend\n" 1943 "-nic none use it alone to have zero network devices (the default is to\n" 1944 " provided a 'user' network connection)\n", 1945 QEMU_ARCH_ALL) 1946DEF("net", HAS_ARG, QEMU_OPTION_net, 1947 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1948 " configure or create an on-board (or machine default) NIC and\n" 1949 " connect it to hub 0 (please use -nic unless you need a hub)\n" 1950 "-net [" 1951#ifdef CONFIG_SLIRP 1952 "user|" 1953#endif 1954 "tap|" 1955 "bridge|" 1956#ifdef CONFIG_VDE 1957 "vde|" 1958#endif 1959#ifdef CONFIG_NETMAP 1960 "netmap|" 1961#endif 1962 "socket][,option][,option][,...]\n" 1963 " old way to initialize a host network interface\n" 1964 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 1965STEXI 1966@item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn] 1967@findex -nic 1968This option is a shortcut for configuring both the on-board (default) guest 1969NIC hardware and the host network backend in one go. The host backend options 1970are the same as with the corresponding @option{-netdev} options below. 1971The guest NIC model can be set with @option{model=@var{modelname}}. 1972Use @option{model=help} to list the available device types. 1973The hardware MAC address can be set with @option{mac=@var{macaddr}}. 1974 1975The following two example do exactly the same, to show how @option{-nic} can 1976be used to shorten the command line length (note that the e1000 is the default 1977on i386, so the @option{model=e1000} parameter could even be omitted here, too): 1978@example 1979qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32 1980qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32 1981@end example 1982 1983@item -nic none 1984Indicate that no network devices should be configured. It is used to override 1985the default configuration (default NIC with ``user'' host network backend) 1986which is activated if no other networking options are provided. 1987 1988@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1989@findex -netdev 1990Configure user mode host network backend which requires no administrator 1991privilege to run. Valid options are: 1992 1993@table @option 1994@item id=@var{id} 1995Assign symbolic name for use in monitor commands. 1996 1997@item ipv4=on|off and ipv6=on|off 1998Specify that either IPv4 or IPv6 must be enabled. If neither is specified 1999both protocols are enabled. 2000 2001@item net=@var{addr}[/@var{mask}] 2002Set IP network address the guest will see. Optionally specify the netmask, 2003either in the form a.b.c.d or as number of valid top-most bits. Default is 200410.0.2.0/24. 2005 2006@item host=@var{addr} 2007Specify the guest-visible address of the host. Default is the 2nd IP in the 2008guest network, i.e. x.x.x.2. 2009 2010@item ipv6-net=@var{addr}[/@var{int}] 2011Set IPv6 network address the guest will see (default is fec0::/64). The 2012network prefix is given in the usual hexadecimal IPv6 address 2013notation. The prefix size is optional, and is given as the number of 2014valid top-most bits (default is 64). 2015 2016@item ipv6-host=@var{addr} 2017Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 2018the guest network, i.e. xxxx::2. 2019 2020@item restrict=on|off 2021If this option is enabled, the guest will be isolated, i.e. it will not be 2022able to contact the host and no guest IP packets will be routed over the host 2023to the outside. This option does not affect any explicitly set forwarding rules. 2024 2025@item hostname=@var{name} 2026Specifies the client hostname reported by the built-in DHCP server. 2027 2028@item dhcpstart=@var{addr} 2029Specify the first of the 16 IPs the built-in DHCP server can assign. Default 2030is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 2031 2032@item dns=@var{addr} 2033Specify the guest-visible address of the virtual nameserver. The address must 2034be different from the host address. Default is the 3rd IP in the guest network, 2035i.e. x.x.x.3. 2036 2037@item ipv6-dns=@var{addr} 2038Specify the guest-visible address of the IPv6 virtual nameserver. The address 2039must be different from the host address. Default is the 3rd IP in the guest 2040network, i.e. xxxx::3. 2041 2042@item dnssearch=@var{domain} 2043Provides an entry for the domain-search list sent by the built-in 2044DHCP server. More than one domain suffix can be transmitted by specifying 2045this option multiple times. If supported, this will cause the guest to 2046automatically try to append the given domain suffix(es) in case a domain name 2047can not be resolved. 2048 2049Example: 2050@example 2051qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org 2052@end example 2053 2054@item domainname=@var{domain} 2055Specifies the client domain name reported by the built-in DHCP server. 2056 2057@item tftp=@var{dir} 2058When using the user mode network stack, activate a built-in TFTP 2059server. The files in @var{dir} will be exposed as the root of a TFTP server. 2060The TFTP client on the guest must be configured in binary mode (use the command 2061@code{bin} of the Unix TFTP client). 2062 2063@item bootfile=@var{file} 2064When using the user mode network stack, broadcast @var{file} as the BOOTP 2065filename. In conjunction with @option{tftp}, this can be used to network boot 2066a guest from a local directory. 2067 2068Example (using pxelinux): 2069@example 2070qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \ 2071 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2072@end example 2073 2074@item smb=@var{dir}[,smbserver=@var{addr}] 2075When using the user mode network stack, activate a built-in SMB 2076server so that Windows OSes can access to the host files in @file{@var{dir}} 2077transparently. The IP address of the SMB server can be set to @var{addr}. By 2078default the 4th IP in the guest network is used, i.e. x.x.x.4. 2079 2080In the guest Windows OS, the line: 2081@example 208210.0.2.4 smbserver 2083@end example 2084must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2085or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2086 2087Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2088 2089Note that a SAMBA server must be installed on the host OS. 2090 2091@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2092Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2093the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2094@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2095given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2096be bound to a specific host interface. If no connection type is set, TCP is 2097used. This option can be given multiple times. 2098 2099For example, to redirect host X11 connection from screen 1 to guest 2100screen 0, use the following: 2101 2102@example 2103# on the host 2104qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 2105# this host xterm should open in the guest X11 server 2106xterm -display :1 2107@end example 2108 2109To redirect telnet connections from host port 5555 to telnet port on 2110the guest, use the following: 2111 2112@example 2113# on the host 2114qemu-system-i386 -nic user,hostfwd=tcp::5555-:23 2115telnet localhost 5555 2116@end example 2117 2118Then when you use on the host @code{telnet localhost 5555}, you 2119connect to the guest telnet server. 2120 2121@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2122@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2123Forward guest TCP connections to the IP address @var{server} on port @var{port} 2124to the character device @var{dev} or to a program executed by @var{cmd:command} 2125which gets spawned for each connection. This option can be given multiple times. 2126 2127You can either use a chardev directly and have that one used throughout QEMU's 2128lifetime, like in the following example: 2129 2130@example 2131# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2132# the guest accesses it 2133qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 2134@end example 2135 2136Or you can execute a command on every TCP connection established by the guest, 2137so that QEMU behaves similar to an inetd process for that virtual server: 2138 2139@example 2140# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2141# and connect the TCP stream to its stdin/stdout 2142qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2143@end example 2144 2145@end table 2146 2147@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2148Configure a host TAP network backend with ID @var{id}. 2149 2150Use the network script @var{file} to configure it and the network script 2151@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2152automatically provides one. The default network configure script is 2153@file{/etc/qemu-ifup} and the default network deconfigure script is 2154@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2155to disable script execution. 2156 2157If running QEMU as an unprivileged user, use the network helper 2158@var{helper} to configure the TAP interface and attach it to the bridge. 2159The default network helper executable is @file{/path/to/qemu-bridge-helper} 2160and the default bridge device is @file{br0}. 2161 2162@option{fd}=@var{h} can be used to specify the handle of an already 2163opened host TAP interface. 2164 2165Examples: 2166 2167@example 2168#launch a QEMU instance with the default network script 2169qemu-system-i386 linux.img -nic tap 2170@end example 2171 2172@example 2173#launch a QEMU instance with two NICs, each one connected 2174#to a TAP device 2175qemu-system-i386 linux.img \ 2176 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \ 2177 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1 2178@end example 2179 2180@example 2181#launch a QEMU instance with the default network helper to 2182#connect a TAP device to bridge br0 2183qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \ 2184 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper" 2185@end example 2186 2187@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2188Connect a host TAP network interface to a host bridge device. 2189 2190Use the network helper @var{helper} to configure the TAP interface and 2191attach it to the bridge. The default network helper executable is 2192@file{/path/to/qemu-bridge-helper} and the default bridge 2193device is @file{br0}. 2194 2195Examples: 2196 2197@example 2198#launch a QEMU instance with the default network helper to 2199#connect a TAP device to bridge br0 2200qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1 2201@end example 2202 2203@example 2204#launch a QEMU instance with the default network helper to 2205#connect a TAP device to bridge qemubr0 2206qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1 2207@end example 2208 2209@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2210 2211This host network backend can be used to connect the guest's network to 2212another QEMU virtual machine using a TCP socket connection. If @option{listen} 2213is specified, QEMU waits for incoming connections on @var{port} 2214(@var{host} is optional). @option{connect} is used to connect to 2215another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2216specifies an already opened TCP socket. 2217 2218Example: 2219@example 2220# launch a first QEMU instance 2221qemu-system-i386 linux.img \ 2222 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2223 -netdev socket,id=n1,listen=:1234 2224# connect the network of this instance to the network of the first instance 2225qemu-system-i386 linux.img \ 2226 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2227 -netdev socket,id=n2,connect=127.0.0.1:1234 2228@end example 2229 2230@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2231 2232Configure a socket host network backend to share the guest's network traffic 2233with another QEMU virtual machines using a UDP multicast socket, effectively 2234making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. 2235NOTES: 2236@enumerate 2237@item 2238Several QEMU can be running on different hosts and share same bus (assuming 2239correct multicast setup for these hosts). 2240@item 2241mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2242@url{http://user-mode-linux.sf.net}. 2243@item 2244Use @option{fd=h} to specify an already opened UDP multicast socket. 2245@end enumerate 2246 2247Example: 2248@example 2249# launch one QEMU instance 2250qemu-system-i386 linux.img \ 2251 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2252 -netdev socket,id=n1,mcast=230.0.0.1:1234 2253# launch another QEMU instance on same "bus" 2254qemu-system-i386 linux.img \ 2255 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2256 -netdev socket,id=n2,mcast=230.0.0.1:1234 2257# launch yet another QEMU instance on same "bus" 2258qemu-system-i386 linux.img \ 2259 -device e1000,netdev=n3,macaddr=52:54:00:12:34:58 \ 2260 -netdev socket,id=n3,mcast=230.0.0.1:1234 2261@end example 2262 2263Example (User Mode Linux compat.): 2264@example 2265# launch QEMU instance (note mcast address selected is UML's default) 2266qemu-system-i386 linux.img \ 2267 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2268 -netdev socket,id=n1,mcast=239.192.168.1:1102 2269# launch UML 2270/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2271@end example 2272 2273Example (send packets from host's 1.2.3.4): 2274@example 2275qemu-system-i386 linux.img \ 2276 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2277 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2278@end example 2279 2280@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}] 2281Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a 2282popular protocol to transport Ethernet (and other Layer 2) data frames between 2283two systems. It is present in routers, firewalls and the Linux kernel 2284(from version 3.3 onwards). 2285 2286This transport allows a VM to communicate to another VM, router or firewall directly. 2287 2288@table @option 2289@item src=@var{srcaddr} 2290 source address (mandatory) 2291@item dst=@var{dstaddr} 2292 destination address (mandatory) 2293@item udp 2294 select udp encapsulation (default is ip). 2295@item srcport=@var{srcport} 2296 source udp port. 2297@item dstport=@var{dstport} 2298 destination udp port. 2299@item ipv6 2300 force v6, otherwise defaults to v4. 2301@item rxcookie=@var{rxcookie} 2302@itemx txcookie=@var{txcookie} 2303 Cookies are a weak form of security in the l2tpv3 specification. 2304Their function is mostly to prevent misconfiguration. By default they are 32 2305bit. 2306@item cookie64 2307 Set cookie size to 64 bit instead of the default 32 2308@item counter=off 2309 Force a 'cut-down' L2TPv3 with no counter as in 2310draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2311@item pincounter=on 2312 Work around broken counter handling in peer. This may also help on 2313networks which have packet reorder. 2314@item offset=@var{offset} 2315 Add an extra offset between header and data 2316@end table 2317 2318For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2319on the remote Linux host 1.2.3.4: 2320@example 2321# Setup tunnel on linux host using raw ip as encapsulation 2322# on 1.2.3.4 2323ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2324 encap udp udp_sport 16384 udp_dport 16384 2325ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2326 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2327ifconfig vmtunnel0 mtu 1500 2328ifconfig vmtunnel0 up 2329brctl addif br-lan vmtunnel0 2330 2331 2332# on 4.3.2.1 2333# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2334 2335qemu-system-i386 linux.img -device e1000,netdev=n1 \ 2336 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2337 2338@end example 2339 2340@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2341Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and 2342listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2343and MODE @var{octalmode} to change default ownership and permissions for 2344communication port. This option is only available if QEMU has been compiled 2345with vde support enabled. 2346 2347Example: 2348@example 2349# launch vde switch 2350vde_switch -F -sock /tmp/myswitch 2351# launch QEMU instance 2352qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch 2353@end example 2354 2355@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2356 2357Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2358be a unix domain socket backed one. The vhost-user uses a specifically defined 2359protocol to pass vhost ioctl replacement messages to an application on the other 2360end of the socket. On non-MSIX guests, the feature can be forced with 2361@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2362be created for multiqueue vhost-user. 2363 2364Example: 2365@example 2366qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2367 -numa node,memdev=mem \ 2368 -chardev socket,id=chr0,path=/path/to/socket \ 2369 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2370 -device virtio-net-pci,netdev=net0 2371@end example 2372 2373@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}] 2374 2375Create a hub port on the emulated hub with ID @var{hubid}. 2376 2377The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a 2378single netdev. Alternatively, you can also connect the hubport to another 2379netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option. 2380 2381@item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2382@findex -net 2383Legacy option to configure or create an on-board (or machine default) Network 2384Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. 2385the default hub), or to the netdev @var{nd}. 2386The NIC is an e1000 by default on the PC target. Optionally, the MAC address 2387can be changed to @var{mac}, the device address set to @var{addr} (PCI cards 2388only), and a @var{name} can be assigned for use in monitor commands. 2389Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2390that the card should have; this option currently only affects virtio cards; set 2391@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2392NIC is created. QEMU can emulate several different models of network card. 2393Use @code{-net nic,model=help} for a list of available devices for your target. 2394 2395@item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}] 2396Configure a host network backend (with the options corresponding to the same 2397@option{-netdev} option) and connect it to the emulated hub 0 (the default 2398hub). Use @var{name} to specify the name of the hub port. 2399ETEXI 2400 2401STEXI 2402@end table 2403ETEXI 2404DEFHEADING() 2405 2406DEFHEADING(Character device options:) 2407 2408DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2409 "-chardev help\n" 2410 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2411 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2412 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n" 2413 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2414 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n" 2415 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2416 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2417 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2418 " [,logfile=PATH][,logappend=on|off]\n" 2419 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2420 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2421 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2422 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2423 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2424 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2425#ifdef _WIN32 2426 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2427 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2428#else 2429 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2430 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2431#endif 2432#ifdef CONFIG_BRLAPI 2433 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2434#endif 2435#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2436 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2437 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2438 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2439#endif 2440#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2441 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2442 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2443#endif 2444#if defined(CONFIG_SPICE) 2445 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2446 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2447#endif 2448 , QEMU_ARCH_ALL 2449) 2450 2451STEXI 2452 2453The general form of a character device option is: 2454@table @option 2455@item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}] 2456@findex -chardev 2457Backend is one of: 2458@option{null}, 2459@option{socket}, 2460@option{udp}, 2461@option{msmouse}, 2462@option{vc}, 2463@option{ringbuf}, 2464@option{file}, 2465@option{pipe}, 2466@option{console}, 2467@option{serial}, 2468@option{pty}, 2469@option{stdio}, 2470@option{braille}, 2471@option{tty}, 2472@option{parallel}, 2473@option{parport}, 2474@option{spicevmc}, 2475@option{spiceport}. 2476The specific backend will determine the applicable options. 2477 2478Use @code{-chardev help} to print all available chardev backend types. 2479 2480All devices must have an id, which can be any string up to 127 characters long. 2481It is used to uniquely identify this device in other command line directives. 2482 2483A character device may be used in multiplexing mode by multiple front-ends. 2484Specify @option{mux=on} to enable this mode. 2485A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2486backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2487If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2488create a multiplexer with your specified ID, and you can then configure multiple 2489front ends to use that chardev ID for their input/output. Up to four different 2490front ends can be connected to a single multiplexed chardev. (Without 2491multiplexing enabled, a chardev can only be used by a single front end.) 2492For instance you could use this to allow a single stdio chardev to be used by 2493two serial ports and the QEMU monitor: 2494 2495@example 2496-chardev stdio,mux=on,id=char0 \ 2497-mon chardev=char0,mode=readline \ 2498-serial chardev:char0 \ 2499-serial chardev:char0 2500@end example 2501 2502You can have more than one multiplexer in a system configuration; for instance 2503you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2504multiplexed between the QEMU monitor and a parallel port: 2505 2506@example 2507-chardev stdio,mux=on,id=char0 \ 2508-mon chardev=char0,mode=readline \ 2509-parallel chardev:char0 \ 2510-chardev tcp,...,mux=on,id=char1 \ 2511-serial chardev:char1 \ 2512-serial chardev:char1 2513@end example 2514 2515When you're using a multiplexed character device, some escape sequences are 2516interpreted in the input. @xref{mux_keys, Keys in the character backend 2517multiplexer}. 2518 2519Note that some other command line options may implicitly create multiplexed 2520character backends; for instance @option{-serial mon:stdio} creates a 2521multiplexed stdio backend connected to the serial port and the QEMU monitor, 2522and @option{-nographic} also multiplexes the console and the monitor to 2523stdio. 2524 2525There is currently no support for multiplexing in the other direction 2526(where a single QEMU front end takes input and output from multiple chardevs). 2527 2528Every backend supports the @option{logfile} option, which supplies the path 2529to a file to record all data transmitted via the backend. The @option{logappend} 2530option controls whether the log file will be truncated or appended to when 2531opened. 2532 2533@end table 2534 2535The available backends are: 2536 2537@table @option 2538@item -chardev null,id=@var{id} 2539A void device. This device will not emit any data, and will drop any data it 2540receives. The null backend does not take any options. 2541 2542@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,reconnect=@var{seconds}][,tls-creds=@var{id}] 2543 2544Create a two-way stream socket, which can be either a TCP or a unix socket. A 2545unix socket will be created if @option{path} is specified. Behaviour is 2546undefined if TCP options are specified for a unix socket. 2547 2548@option{server} specifies that the socket shall be a listening socket. 2549 2550@option{nowait} specifies that QEMU should not block waiting for a client to 2551connect to a listening socket. 2552 2553@option{telnet} specifies that traffic on the socket should interpret telnet 2554escape sequences. 2555 2556@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2557the remote end goes away. qemu will delay this many seconds and then attempt 2558to reconnect. Zero disables reconnecting, and is the default. 2559 2560@option{tls-creds} requests enablement of the TLS protocol for encryption, 2561and specifies the id of the TLS credentials to use for the handshake. The 2562credentials must be previously created with the @option{-object tls-creds} 2563argument. 2564 2565TCP and unix socket options are given below: 2566 2567@table @option 2568 2569@item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay] 2570 2571@option{host} for a listening socket specifies the local address to be bound. 2572For a connecting socket species the remote host to connect to. @option{host} is 2573optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2574 2575@option{port} for a listening socket specifies the local port to be bound. For a 2576connecting socket specifies the port on the remote host to connect to. 2577@option{port} can be given as either a port number or a service name. 2578@option{port} is required. 2579 2580@option{to} is only relevant to listening sockets. If it is specified, and 2581@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2582to and including @option{to} until it succeeds. @option{to} must be specified 2583as a port number. 2584 2585@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2586If neither is specified the socket may use either protocol. 2587 2588@option{nodelay} disables the Nagle algorithm. 2589 2590@item unix options: path=@var{path} 2591 2592@option{path} specifies the local path of the unix socket. @option{path} is 2593required. 2594 2595@end table 2596 2597@item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6] 2598 2599Sends all traffic from the guest to a remote host over UDP. 2600 2601@option{host} specifies the remote host to connect to. If not specified it 2602defaults to @code{localhost}. 2603 2604@option{port} specifies the port on the remote host to connect to. @option{port} 2605is required. 2606 2607@option{localaddr} specifies the local address to bind to. If not specified it 2608defaults to @code{0.0.0.0}. 2609 2610@option{localport} specifies the local port to bind to. If not specified any 2611available local port will be used. 2612 2613@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2614If neither is specified the device may use either protocol. 2615 2616@item -chardev msmouse,id=@var{id} 2617 2618Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2619take any options. 2620 2621@item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]] 2622 2623Connect to a QEMU text console. @option{vc} may optionally be given a specific 2624size. 2625 2626@option{width} and @option{height} specify the width and height respectively of 2627the console, in pixels. 2628 2629@option{cols} and @option{rows} specify that the console be sized to fit a text 2630console with the given dimensions. 2631 2632@item -chardev ringbuf,id=@var{id}[,size=@var{size}] 2633 2634Create a ring buffer with fixed size @option{size}. 2635@var{size} must be a power of two and defaults to @code{64K}. 2636 2637@item -chardev file,id=@var{id},path=@var{path} 2638 2639Log all traffic received from the guest to a file. 2640 2641@option{path} specifies the path of the file to be opened. This file will be 2642created if it does not already exist, and overwritten if it does. @option{path} 2643is required. 2644 2645@item -chardev pipe,id=@var{id},path=@var{path} 2646 2647Create a two-way connection to the guest. The behaviour differs slightly between 2648Windows hosts and other hosts: 2649 2650On Windows, a single duplex pipe will be created at 2651@file{\\.pipe\@option{path}}. 2652 2653On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2654@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2655received by the guest. Data written by the guest can be read from 2656@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2657be present. 2658 2659@option{path} forms part of the pipe path as described above. @option{path} is 2660required. 2661 2662@item -chardev console,id=@var{id} 2663 2664Send traffic from the guest to QEMU's standard output. @option{console} does not 2665take any options. 2666 2667@option{console} is only available on Windows hosts. 2668 2669@item -chardev serial,id=@var{id},path=@option{path} 2670 2671Send traffic from the guest to a serial device on the host. 2672 2673On Unix hosts serial will actually accept any tty device, 2674not only serial lines. 2675 2676@option{path} specifies the name of the serial device to open. 2677 2678@item -chardev pty,id=@var{id} 2679 2680Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2681not take any options. 2682 2683@option{pty} is not available on Windows hosts. 2684 2685@item -chardev stdio,id=@var{id}[,signal=on|off] 2686Connect to standard input and standard output of the QEMU process. 2687 2688@option{signal} controls if signals are enabled on the terminal, that includes 2689exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2690default, use @option{signal=off} to disable it. 2691 2692@item -chardev braille,id=@var{id} 2693 2694Connect to a local BrlAPI server. @option{braille} does not take any options. 2695 2696@item -chardev tty,id=@var{id},path=@var{path} 2697 2698@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2699DragonFlyBSD hosts. It is an alias for @option{serial}. 2700 2701@option{path} specifies the path to the tty. @option{path} is required. 2702 2703@item -chardev parallel,id=@var{id},path=@var{path} 2704@itemx -chardev parport,id=@var{id},path=@var{path} 2705 2706@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2707 2708Connect to a local parallel port. 2709 2710@option{path} specifies the path to the parallel port device. @option{path} is 2711required. 2712 2713@item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name} 2714 2715@option{spicevmc} is only available when spice support is built in. 2716 2717@option{debug} debug level for spicevmc 2718 2719@option{name} name of spice channel to connect to 2720 2721Connect to a spice virtual machine channel, such as vdiport. 2722 2723@item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name} 2724 2725@option{spiceport} is only available when spice support is built in. 2726 2727@option{debug} debug level for spicevmc 2728 2729@option{name} name of spice port to connect to 2730 2731Connect to a spice port, allowing a Spice client to handle the traffic 2732identified by a name (preferably a fqdn). 2733ETEXI 2734 2735STEXI 2736@end table 2737ETEXI 2738DEFHEADING() 2739 2740DEFHEADING(Bluetooth(R) options:) 2741STEXI 2742@table @option 2743ETEXI 2744 2745DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2746 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2747 "-bt hci,host[:id]\n" \ 2748 " use host's HCI with the given name\n" \ 2749 "-bt hci[,vlan=n]\n" \ 2750 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2751 "-bt vhci[,vlan=n]\n" \ 2752 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2753 "-bt device:dev[,vlan=n]\n" \ 2754 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2755 QEMU_ARCH_ALL) 2756STEXI 2757@item -bt hci[...] 2758@findex -bt 2759Defines the function of the corresponding Bluetooth HCI. -bt options 2760are matched with the HCIs present in the chosen machine type. For 2761example when emulating a machine with only one HCI built into it, only 2762the first @code{-bt hci[...]} option is valid and defines the HCI's 2763logic. The Transport Layer is decided by the machine type. Currently 2764the machines @code{n800} and @code{n810} have one HCI and all other 2765machines have none. 2766 2767@anchor{bt-hcis} 2768The following three types are recognized: 2769 2770@table @option 2771@item -bt hci,null 2772(default) The corresponding Bluetooth HCI assumes no internal logic 2773and will not respond to any HCI commands or emit events. 2774 2775@item -bt hci,host[:@var{id}] 2776(@code{bluez} only) The corresponding HCI passes commands / events 2777to / from the physical HCI identified by the name @var{id} (default: 2778@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2779capable systems like Linux. 2780 2781@item -bt hci[,vlan=@var{n}] 2782Add a virtual, standard HCI that will participate in the Bluetooth 2783scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2784VLANs, devices inside a bluetooth network @var{n} can only communicate 2785with other devices in the same network (scatternet). 2786@end table 2787 2788@item -bt vhci[,vlan=@var{n}] 2789(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2790to the host bluetooth stack instead of to the emulated target. This 2791allows the host and target machines to participate in a common scatternet 2792and communicate. Requires the Linux @code{vhci} driver installed. Can 2793be used as following: 2794 2795@example 2796qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2797@end example 2798 2799@item -bt device:@var{dev}[,vlan=@var{n}] 2800Emulate a bluetooth device @var{dev} and place it in network @var{n} 2801(default @code{0}). QEMU can only emulate one type of bluetooth devices 2802currently: 2803 2804@table @option 2805@item keyboard 2806Virtual wireless keyboard implementing the HIDP bluetooth profile. 2807@end table 2808ETEXI 2809 2810STEXI 2811@end table 2812ETEXI 2813DEFHEADING() 2814 2815#ifdef CONFIG_TPM 2816DEFHEADING(TPM device options:) 2817 2818DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2819 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2820 " use path to provide path to a character device; default is /dev/tpm0\n" 2821 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2822 " not provided it will be searched for in /sys/class/misc/tpm?/device\n" 2823 "-tpmdev emulator,id=id,chardev=dev\n" 2824 " configure the TPM device using chardev backend\n", 2825 QEMU_ARCH_ALL) 2826STEXI 2827 2828The general form of a TPM device option is: 2829@table @option 2830 2831@item -tpmdev @var{backend},id=@var{id}[,@var{options}] 2832@findex -tpmdev 2833 2834The specific backend type will determine the applicable options. 2835The @code{-tpmdev} option creates the TPM backend and requires a 2836@code{-device} option that specifies the TPM frontend interface model. 2837 2838Use @code{-tpmdev help} to print all available TPM backend types. 2839 2840@end table 2841 2842The available backends are: 2843 2844@table @option 2845 2846@item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path} 2847 2848(Linux-host only) Enable access to the host's TPM using the passthrough 2849driver. 2850 2851@option{path} specifies the path to the host's TPM device, i.e., on 2852a Linux host this would be @code{/dev/tpm0}. 2853@option{path} is optional and by default @code{/dev/tpm0} is used. 2854 2855@option{cancel-path} specifies the path to the host TPM device's sysfs 2856entry allowing for cancellation of an ongoing TPM command. 2857@option{cancel-path} is optional and by default QEMU will search for the 2858sysfs entry to use. 2859 2860Some notes about using the host's TPM with the passthrough driver: 2861 2862The TPM device accessed by the passthrough driver must not be 2863used by any other application on the host. 2864 2865Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2866the VM's firmware (BIOS/UEFI) will not be able to initialize the 2867TPM again and may therefore not show a TPM-specific menu that would 2868otherwise allow the user to configure the TPM, e.g., allow the user to 2869enable/disable or activate/deactivate the TPM. 2870Further, if TPM ownership is released from within a VM then the host's TPM 2871will get disabled and deactivated. To enable and activate the 2872TPM again afterwards, the host has to be rebooted and the user is 2873required to enter the firmware's menu to enable and activate the TPM. 2874If the TPM is left disabled and/or deactivated most TPM commands will fail. 2875 2876To create a passthrough TPM use the following two options: 2877@example 2878-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2879@end example 2880Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2881@code{tpmdev=tpm0} in the device option. 2882 2883@item -tpmdev emulator,id=@var{id},chardev=@var{dev} 2884 2885(Linux-host only) Enable access to a TPM emulator using Unix domain socket based 2886chardev backend. 2887 2888@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server. 2889 2890To create a TPM emulator backend device with chardev socket backend: 2891@example 2892 2893-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0 2894 2895@end example 2896 2897ETEXI 2898 2899STEXI 2900@end table 2901ETEXI 2902DEFHEADING() 2903 2904#endif 2905 2906DEFHEADING(Linux/Multiboot boot specific:) 2907STEXI 2908 2909When using these options, you can use a given Linux or Multiboot 2910kernel without installing it in the disk image. It can be useful 2911for easier testing of various kernels. 2912 2913@table @option 2914ETEXI 2915 2916DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2917 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2918STEXI 2919@item -kernel @var{bzImage} 2920@findex -kernel 2921Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2922or in multiboot format. 2923ETEXI 2924 2925DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2926 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2927STEXI 2928@item -append @var{cmdline} 2929@findex -append 2930Use @var{cmdline} as kernel command line 2931ETEXI 2932 2933DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2934 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2935STEXI 2936@item -initrd @var{file} 2937@findex -initrd 2938Use @var{file} as initial ram disk. 2939 2940@item -initrd "@var{file1} arg=foo,@var{file2}" 2941 2942This syntax is only available with multiboot. 2943 2944Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2945first module. 2946ETEXI 2947 2948DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2949 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2950STEXI 2951@item -dtb @var{file} 2952@findex -dtb 2953Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2954on boot. 2955ETEXI 2956 2957STEXI 2958@end table 2959ETEXI 2960DEFHEADING() 2961 2962DEFHEADING(Debug/Expert options:) 2963STEXI 2964@table @option 2965ETEXI 2966 2967DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 2968 "-fw_cfg [name=]<name>,file=<file>\n" 2969 " add named fw_cfg entry with contents from file\n" 2970 "-fw_cfg [name=]<name>,string=<str>\n" 2971 " add named fw_cfg entry with contents from string\n", 2972 QEMU_ARCH_ALL) 2973STEXI 2974 2975@item -fw_cfg [name=]@var{name},file=@var{file} 2976@findex -fw_cfg 2977Add named fw_cfg entry with contents from file @var{file}. 2978 2979@item -fw_cfg [name=]@var{name},string=@var{str} 2980Add named fw_cfg entry with contents from string @var{str}. 2981 2982The terminating NUL character of the contents of @var{str} will not be 2983included as part of the fw_cfg item data. To insert contents with 2984embedded NUL characters, you have to use the @var{file} parameter. 2985 2986The fw_cfg entries are passed by QEMU through to the guest. 2987 2988Example: 2989@example 2990 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 2991@end example 2992creates an fw_cfg entry named opt/com.mycompany/blob with contents 2993from ./my_blob.bin. 2994 2995ETEXI 2996 2997DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 2998 "-serial dev redirect the serial port to char device 'dev'\n", 2999 QEMU_ARCH_ALL) 3000STEXI 3001@item -serial @var{dev} 3002@findex -serial 3003Redirect the virtual serial port to host character device 3004@var{dev}. The default device is @code{vc} in graphical mode and 3005@code{stdio} in non graphical mode. 3006 3007This option can be used several times to simulate up to 4 serial 3008ports. 3009 3010Use @code{-serial none} to disable all serial ports. 3011 3012Available character devices are: 3013@table @option 3014@item vc[:@var{W}x@var{H}] 3015Virtual console. Optionally, a width and height can be given in pixel with 3016@example 3017vc:800x600 3018@end example 3019It is also possible to specify width or height in characters: 3020@example 3021vc:80Cx24C 3022@end example 3023@item pty 3024[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3025@item none 3026No device is allocated. 3027@item null 3028void device 3029@item chardev:@var{id} 3030Use a named character device defined with the @code{-chardev} option. 3031@item /dev/XXX 3032[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3033parameters are set according to the emulated ones. 3034@item /dev/parport@var{N} 3035[Linux only, parallel port only] Use host parallel port 3036@var{N}. Currently SPP and EPP parallel port features can be used. 3037@item file:@var{filename} 3038Write output to @var{filename}. No character can be read. 3039@item stdio 3040[Unix only] standard input/output 3041@item pipe:@var{filename} 3042name pipe @var{filename} 3043@item COM@var{n} 3044[Windows only] Use host serial port @var{n} 3045@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3046This implements UDP Net Console. 3047When @var{remote_host} or @var{src_ip} are not specified 3048they default to @code{0.0.0.0}. 3049When not using a specified @var{src_port} a random port is automatically chosen. 3050 3051If you just want a simple readonly console you can use @code{netcat} or 3052@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3053@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3054will appear in the netconsole session. 3055 3056If you plan to send characters back via netconsole or you want to stop 3057and start QEMU a lot of times, you should have QEMU use the same 3058source port each time by using something like @code{-serial 3059udp::4555@@:4556} to QEMU. Another approach is to use a patched 3060version of netcat which can listen to a TCP port and send and receive 3061characters via udp. If you have a patched version of netcat which 3062activates telnet remote echo and single char transfer, then you can 3063use the following options to set up a netcat redirector to allow 3064telnet on port 5555 to access the QEMU port. 3065@table @code 3066@item QEMU Options: 3067-serial udp::4555@@:4556 3068@item netcat options: 3069-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3070@item telnet options: 3071localhost 5555 3072@end table 3073 3074@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3075The TCP Net Console has two modes of operation. It can send the serial 3076I/O to a location or wait for a connection from a location. By default 3077the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3078the @var{server} option QEMU will wait for a client socket application 3079to connect to the port before continuing, unless the @code{nowait} 3080option was specified. The @code{nodelay} option disables the Nagle buffering 3081algorithm. The @code{reconnect} option only applies if @var{noserver} is 3082set, if the connection goes down it will attempt to reconnect at the 3083given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3084one TCP connection at a time is accepted. You can use @code{telnet} to 3085connect to the corresponding character device. 3086@table @code 3087@item Example to send tcp console to 192.168.0.2 port 4444 3088-serial tcp:192.168.0.2:4444 3089@item Example to listen and wait on port 4444 for connection 3090-serial tcp::4444,server 3091@item Example to not wait and listen on ip 192.168.0.100 port 4444 3092-serial tcp:192.168.0.100:4444,server,nowait 3093@end table 3094 3095@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3096The telnet protocol is used instead of raw tcp sockets. The options 3097work the same as if you had specified @code{-serial tcp}. The 3098difference is that the port acts like a telnet server or client using 3099telnet option negotiation. This will also allow you to send the 3100MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3101sequence. Typically in unix telnet you do it with Control-] and then 3102type "send break" followed by pressing the enter key. 3103 3104@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3105A unix domain socket is used instead of a tcp socket. The option works the 3106same as if you had specified @code{-serial tcp} except the unix domain socket 3107@var{path} is used for connections. 3108 3109@item mon:@var{dev_string} 3110This is a special option to allow the monitor to be multiplexed onto 3111another serial port. The monitor is accessed with key sequence of 3112@key{Control-a} and then pressing @key{c}. 3113@var{dev_string} should be any one of the serial devices specified 3114above. An example to multiplex the monitor onto a telnet server 3115listening on port 4444 would be: 3116@table @code 3117@item -serial mon:telnet::4444,server,nowait 3118@end table 3119When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3120QEMU any more but will be passed to the guest instead. 3121 3122@item braille 3123Braille device. This will use BrlAPI to display the braille output on a real 3124or fake device. 3125 3126@item msmouse 3127Three button serial mouse. Configure the guest to use Microsoft protocol. 3128@end table 3129ETEXI 3130 3131DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3132 "-parallel dev redirect the parallel port to char device 'dev'\n", 3133 QEMU_ARCH_ALL) 3134STEXI 3135@item -parallel @var{dev} 3136@findex -parallel 3137Redirect the virtual parallel port to host device @var{dev} (same 3138devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3139be used to use hardware devices connected on the corresponding host 3140parallel port. 3141 3142This option can be used several times to simulate up to 3 parallel 3143ports. 3144 3145Use @code{-parallel none} to disable all parallel ports. 3146ETEXI 3147 3148DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3149 "-monitor dev redirect the monitor to char device 'dev'\n", 3150 QEMU_ARCH_ALL) 3151STEXI 3152@item -monitor @var{dev} 3153@findex -monitor 3154Redirect the monitor to host device @var{dev} (same devices as the 3155serial port). 3156The default device is @code{vc} in graphical mode and @code{stdio} in 3157non graphical mode. 3158Use @code{-monitor none} to disable the default monitor. 3159ETEXI 3160DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3161 "-qmp dev like -monitor but opens in 'control' mode\n", 3162 QEMU_ARCH_ALL) 3163STEXI 3164@item -qmp @var{dev} 3165@findex -qmp 3166Like -monitor but opens in 'control' mode. 3167ETEXI 3168DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3169 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3170 QEMU_ARCH_ALL) 3171STEXI 3172@item -qmp-pretty @var{dev} 3173@findex -qmp-pretty 3174Like -qmp but uses pretty JSON formatting. 3175ETEXI 3176 3177DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3178 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL) 3179STEXI 3180@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]] 3181@findex -mon 3182Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing 3183easing human reading and debugging. 3184ETEXI 3185 3186DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3187 "-debugcon dev redirect the debug console to char device 'dev'\n", 3188 QEMU_ARCH_ALL) 3189STEXI 3190@item -debugcon @var{dev} 3191@findex -debugcon 3192Redirect the debug console to host device @var{dev} (same devices as the 3193serial port). The debug console is an I/O port which is typically port 31940xe9; writing to that I/O port sends output to this device. 3195The default device is @code{vc} in graphical mode and @code{stdio} in 3196non graphical mode. 3197ETEXI 3198 3199DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3200 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3201STEXI 3202@item -pidfile @var{file} 3203@findex -pidfile 3204Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3205from a script. 3206ETEXI 3207 3208DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3209 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3210STEXI 3211@item -singlestep 3212@findex -singlestep 3213Run the emulation in single step mode. 3214ETEXI 3215 3216DEF("preconfig", 0, QEMU_OPTION_preconfig, \ 3217 "--preconfig pause QEMU before machine is initialized (experimental)\n", 3218 QEMU_ARCH_ALL) 3219STEXI 3220@item --preconfig 3221@findex --preconfig 3222Pause QEMU for interactive configuration before the machine is created, 3223which allows querying and configuring properties that will affect 3224machine initialization. Use QMP command 'x-exit-preconfig' to exit 3225the preconfig state and move to the next state (i.e. run guest if -S 3226isn't used or pause the second time if -S is used). This option is 3227experimental. 3228ETEXI 3229 3230DEF("S", 0, QEMU_OPTION_S, \ 3231 "-S freeze CPU at startup (use 'c' to start execution)\n", 3232 QEMU_ARCH_ALL) 3233STEXI 3234@item -S 3235@findex -S 3236Do not start CPU at startup (you must type 'c' in the monitor). 3237ETEXI 3238 3239DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3240 "-realtime [mlock=on|off]\n" 3241 " run qemu with realtime features\n" 3242 " mlock=on|off controls mlock support (default: on)\n", 3243 QEMU_ARCH_ALL) 3244STEXI 3245@item -realtime mlock=on|off 3246@findex -realtime 3247Run qemu with realtime features. 3248mlocking qemu and guest memory can be enabled via @option{mlock=on} 3249(enabled by default). 3250ETEXI 3251 3252DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, 3253 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" 3254 " run qemu with overcommit hints\n" 3255 " mem-lock=on|off controls memory lock support (default: off)\n" 3256 " cpu-pm=on|off controls cpu power management (default: off)\n", 3257 QEMU_ARCH_ALL) 3258STEXI 3259@item -overcommit mem-lock=on|off 3260@item -overcommit cpu-pm=on|off 3261@findex -overcommit 3262Run qemu with hints about host resource overcommit. The default is 3263to assume that host overcommits all resources. 3264 3265Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled 3266by default). This works when host memory is not overcommitted and reduces the 3267worst-case latency for guest. This is equivalent to @option{realtime}. 3268 3269Guest ability to manage power state of host cpus (increasing latency for other 3270processes on the same host cpu, but decreasing latency for guest) can be 3271enabled via @option{cpu-pm=on} (disabled by default). This works best when 3272host CPU is not overcommitted. When used, host estimates of CPU cycle and power 3273utilization will be incorrect, not taking into account guest idle time. 3274ETEXI 3275 3276DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3277 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3278STEXI 3279@item -gdb @var{dev} 3280@findex -gdb 3281Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3282connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3283stdio are reasonable use case. The latter is allowing to start QEMU from 3284within gdb and establish the connection via a pipe: 3285@example 3286(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3287@end example 3288ETEXI 3289 3290DEF("s", 0, QEMU_OPTION_s, \ 3291 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3292 QEMU_ARCH_ALL) 3293STEXI 3294@item -s 3295@findex -s 3296Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3297(@pxref{gdb_usage}). 3298ETEXI 3299 3300DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3301 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3302 QEMU_ARCH_ALL) 3303STEXI 3304@item -d @var{item1}[,...] 3305@findex -d 3306Enable logging of specified items. Use '-d help' for a list of log items. 3307ETEXI 3308 3309DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3310 "-D logfile output log to logfile (default stderr)\n", 3311 QEMU_ARCH_ALL) 3312STEXI 3313@item -D @var{logfile} 3314@findex -D 3315Output log in @var{logfile} instead of to stderr 3316ETEXI 3317 3318DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3319 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3320 QEMU_ARCH_ALL) 3321STEXI 3322@item -dfilter @var{range1}[,...] 3323@findex -dfilter 3324Filter debug output to that relevant to a range of target addresses. The filter 3325spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3326@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3327addresses and sizes required. For example: 3328@example 3329 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3330@end example 3331Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3332the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3333block starting at 0xffffffc00005f000. 3334ETEXI 3335 3336DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3337 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3338 QEMU_ARCH_ALL) 3339STEXI 3340@item -L @var{path} 3341@findex -L 3342Set the directory for the BIOS, VGA BIOS and keymaps. 3343 3344To list all the data directories, use @code{-L help}. 3345ETEXI 3346 3347DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3348 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3349STEXI 3350@item -bios @var{file} 3351@findex -bios 3352Set the filename for the BIOS. 3353ETEXI 3354 3355DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3356 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3357STEXI 3358@item -enable-kvm 3359@findex -enable-kvm 3360Enable KVM full virtualization support. This option is only available 3361if KVM support is enabled when compiling. 3362ETEXI 3363 3364DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \ 3365 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386) 3366STEXI 3367@item -enable-hax 3368@findex -enable-hax 3369Enable HAX (Hardware-based Acceleration eXecution) support. This option 3370is only available if HAX support is enabled when compiling. HAX is only 3371applicable to MAC and Windows platform, and thus does not conflict with 3372KVM. This option is deprecated, use @option{-accel hax} instead. 3373ETEXI 3374 3375DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3376 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3377DEF("xen-create", 0, QEMU_OPTION_xen_create, 3378 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3379 " warning: should not be used when xend is in use\n", 3380 QEMU_ARCH_ALL) 3381DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3382 "-xen-attach attach to existing xen domain\n" 3383 " xend will use this when starting QEMU\n", 3384 QEMU_ARCH_ALL) 3385DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict, 3386 "-xen-domid-restrict restrict set of available xen operations\n" 3387 " to specified domain id. (Does not affect\n" 3388 " xenpv machine type).\n", 3389 QEMU_ARCH_ALL) 3390STEXI 3391@item -xen-domid @var{id} 3392@findex -xen-domid 3393Specify xen guest domain @var{id} (XEN only). 3394@item -xen-create 3395@findex -xen-create 3396Create domain using xen hypercalls, bypassing xend. 3397Warning: should not be used when xend is in use (XEN only). 3398@item -xen-attach 3399@findex -xen-attach 3400Attach to existing xen domain. 3401xend will use this when starting QEMU (XEN only). 3402@findex -xen-domid-restrict 3403Restrict set of available xen operations to specified domain id (XEN only). 3404ETEXI 3405 3406DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3407 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3408STEXI 3409@item -no-reboot 3410@findex -no-reboot 3411Exit instead of rebooting. 3412ETEXI 3413 3414DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3415 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3416STEXI 3417@item -no-shutdown 3418@findex -no-shutdown 3419Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3420This allows for instance switching to monitor to commit changes to the 3421disk image. 3422ETEXI 3423 3424DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3425 "-loadvm [tag|id]\n" \ 3426 " start right away with a saved state (loadvm in monitor)\n", 3427 QEMU_ARCH_ALL) 3428STEXI 3429@item -loadvm @var{file} 3430@findex -loadvm 3431Start right away with a saved state (@code{loadvm} in monitor) 3432ETEXI 3433 3434#ifndef _WIN32 3435DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3436 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3437#endif 3438STEXI 3439@item -daemonize 3440@findex -daemonize 3441Daemonize the QEMU process after initialization. QEMU will not detach from 3442standard IO until it is ready to receive connections on any of its devices. 3443This option is a useful way for external programs to launch QEMU without having 3444to cope with initialization race conditions. 3445ETEXI 3446 3447DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3448 "-option-rom rom load a file, rom, into the option ROM space\n", 3449 QEMU_ARCH_ALL) 3450STEXI 3451@item -option-rom @var{file} 3452@findex -option-rom 3453Load the contents of @var{file} as an option ROM. 3454This option is useful to load things like EtherBoot. 3455ETEXI 3456 3457HXCOMM Silently ignored for compatibility 3458DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3459 3460DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3461 "-rtc [base=utc|localtime|<datetime>][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3462 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3463 QEMU_ARCH_ALL) 3464 3465STEXI 3466 3467@item -rtc [base=utc|localtime|@var{datetime}][,clock=host|rt|vm][,driftfix=none|slew] 3468@findex -rtc 3469Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3470UTC or local time, respectively. @code{localtime} is required for correct date in 3471MS-DOS or Windows. To start at a specific point in time, provide @var{datetime} in the 3472format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3473 3474By default the RTC is driven by the host system time. This allows using of the 3475RTC as accurate reference clock inside the guest, specifically if the host 3476time is smoothly following an accurate external reference clock, e.g. via NTP. 3477If you want to isolate the guest time from the host, you can set @option{clock} 3478to @code{rt} instead, which provides a host monotonic clock if host support it. 3479To even prevent the RTC from progressing during suspension, you can set @option{clock} 3480to @code{vm} (virtual clock). @samp{clock=vm} is recommended especially in 3481icount mode in order to preserve determinism; however, note that in icount mode 3482the speed of the virtual clock is variable and can in general differ from the 3483host clock. 3484 3485Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3486specifically with Windows' ACPI HAL. This option will try to figure out how 3487many timer interrupts were not processed by the Windows guest and will 3488re-inject them. 3489ETEXI 3490 3491DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3492 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3493 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3494 " instruction, enable aligning the host and virtual clocks\n" \ 3495 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3496STEXI 3497@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3498@findex -icount 3499Enable virtual instruction counter. The virtual cpu will execute one 3500instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3501then the virtual cpu speed will be automatically adjusted to keep virtual 3502time within a few seconds of real time. 3503 3504When the virtual cpu is sleeping, the virtual time will advance at default 3505speed unless @option{sleep=on|off} is specified. 3506With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3507instantly whenever the virtual cpu goes to sleep mode and will not advance 3508if no timer is enabled. This behavior give deterministic execution times from 3509the guest point of view. 3510 3511Note that while this option can give deterministic behavior, it does not 3512provide cycle accurate emulation. Modern CPUs contain superscalar out of 3513order cores with complex cache hierarchies. The number of instructions 3514executed often has little or no correlation with actual performance. 3515 3516@option{align=on} will activate the delay algorithm which will try 3517to synchronise the host clock and the virtual clock. The goal is to 3518have a guest running at the real frequency imposed by the shift option. 3519Whenever the guest clock is behind the host clock and if 3520@option{align=on} is specified then we print a message to the user 3521to inform about the delay. 3522Currently this option does not work when @option{shift} is @code{auto}. 3523Note: The sync algorithm will work for those shift values for which 3524the guest clock runs ahead of the host clock. Typically this happens 3525when the shift value is high (how high depends on the host machine). 3526 3527When @option{rr} option is specified deterministic record/replay is enabled. 3528Replay log is written into @var{filename} file in record mode and 3529read from this file in replay mode. 3530 3531Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3532at the start of execution recording. In replay mode this option is used 3533to load the initial VM state. 3534ETEXI 3535 3536DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3537 "-watchdog model\n" \ 3538 " enable virtual hardware watchdog [default=none]\n", 3539 QEMU_ARCH_ALL) 3540STEXI 3541@item -watchdog @var{model} 3542@findex -watchdog 3543Create a virtual hardware watchdog device. Once enabled (by a guest 3544action), the watchdog must be periodically polled by an agent inside 3545the guest or else the guest will be restarted. Choose a model for 3546which your guest has drivers. 3547 3548The @var{model} is the model of hardware watchdog to emulate. Use 3549@code{-watchdog help} to list available hardware models. Only one 3550watchdog can be enabled for a guest. 3551 3552The following models may be available: 3553@table @option 3554@item ib700 3555iBASE 700 is a very simple ISA watchdog with a single timer. 3556@item i6300esb 3557Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3558dual-timer watchdog. 3559@item diag288 3560A virtual watchdog for s390x backed by the diagnose 288 hypercall 3561(currently KVM only). 3562@end table 3563ETEXI 3564 3565DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3566 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \ 3567 " action when watchdog fires [default=reset]\n", 3568 QEMU_ARCH_ALL) 3569STEXI 3570@item -watchdog-action @var{action} 3571@findex -watchdog-action 3572 3573The @var{action} controls what QEMU will do when the watchdog timer 3574expires. 3575The default is 3576@code{reset} (forcefully reset the guest). 3577Other possible actions are: 3578@code{shutdown} (attempt to gracefully shutdown the guest), 3579@code{poweroff} (forcefully poweroff the guest), 3580@code{inject-nmi} (inject a NMI into the guest), 3581@code{pause} (pause the guest), 3582@code{debug} (print a debug message and continue), or 3583@code{none} (do nothing). 3584 3585Note that the @code{shutdown} action requires that the guest responds 3586to ACPI signals, which it may not be able to do in the sort of 3587situations where the watchdog would have expired, and thus 3588@code{-watchdog-action shutdown} is not recommended for production use. 3589 3590Examples: 3591 3592@table @code 3593@item -watchdog i6300esb -watchdog-action pause 3594@itemx -watchdog ib700 3595@end table 3596ETEXI 3597 3598DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3599 "-echr chr set terminal escape character instead of ctrl-a\n", 3600 QEMU_ARCH_ALL) 3601STEXI 3602 3603@item -echr @var{numeric_ascii_value} 3604@findex -echr 3605Change the escape character used for switching to the monitor when using 3606monitor and serial sharing. The default is @code{0x01} when using the 3607@code{-nographic} option. @code{0x01} is equal to pressing 3608@code{Control-a}. You can select a different character from the ascii 3609control keys where 1 through 26 map to Control-a through Control-z. For 3610instance you could use the either of the following to change the escape 3611character to Control-t. 3612@table @code 3613@item -echr 0x14 3614@itemx -echr 20 3615@end table 3616ETEXI 3617 3618DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3619 "-virtioconsole c\n" \ 3620 " set virtio console\n", QEMU_ARCH_ALL) 3621STEXI 3622@item -virtioconsole @var{c} 3623@findex -virtioconsole 3624Set virtio console. 3625This option is deprecated, please use @option{-device virtconsole} instead. 3626ETEXI 3627 3628DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3629 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3630STEXI 3631@item -show-cursor 3632@findex -show-cursor 3633Show cursor. 3634ETEXI 3635 3636DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3637 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3638STEXI 3639@item -tb-size @var{n} 3640@findex -tb-size 3641Set TB size. 3642ETEXI 3643 3644DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3645 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3646 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3647 "-incoming unix:socketpath\n" \ 3648 " prepare for incoming migration, listen on\n" \ 3649 " specified protocol and socket address\n" \ 3650 "-incoming fd:fd\n" \ 3651 "-incoming exec:cmdline\n" \ 3652 " accept incoming migration on given file descriptor\n" \ 3653 " or from given external command\n" \ 3654 "-incoming defer\n" \ 3655 " wait for the URI to be specified via migrate_incoming\n", 3656 QEMU_ARCH_ALL) 3657STEXI 3658@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3659@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3660@findex -incoming 3661Prepare for incoming migration, listen on a given tcp port. 3662 3663@item -incoming unix:@var{socketpath} 3664Prepare for incoming migration, listen on a given unix socket. 3665 3666@item -incoming fd:@var{fd} 3667Accept incoming migration from a given filedescriptor. 3668 3669@item -incoming exec:@var{cmdline} 3670Accept incoming migration as an output from specified external command. 3671 3672@item -incoming defer 3673Wait for the URI to be specified via migrate_incoming. The monitor can 3674be used to change settings (such as migration parameters) prior to issuing 3675the migrate_incoming to allow the migration to begin. 3676ETEXI 3677 3678DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3679 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3680STEXI 3681@item -only-migratable 3682@findex -only-migratable 3683Only allow migratable devices. Devices will not be allowed to enter an 3684unmigratable state. 3685ETEXI 3686 3687DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3688 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3689STEXI 3690@item -nodefaults 3691@findex -nodefaults 3692Don't create default devices. Normally, QEMU sets the default devices like serial 3693port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3694CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3695default devices. 3696ETEXI 3697 3698#ifndef _WIN32 3699DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3700 "-chroot dir chroot to dir just before starting the VM\n", 3701 QEMU_ARCH_ALL) 3702#endif 3703STEXI 3704@item -chroot @var{dir} 3705@findex -chroot 3706Immediately before starting guest execution, chroot to the specified 3707directory. Especially useful in combination with -runas. 3708ETEXI 3709 3710#ifndef _WIN32 3711DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3712 "-runas user change to user id user just before starting the VM\n" \ 3713 " user can be numeric uid:gid instead\n", 3714 QEMU_ARCH_ALL) 3715#endif 3716STEXI 3717@item -runas @var{user} 3718@findex -runas 3719Immediately before starting guest execution, drop root privileges, switching 3720to the specified user. 3721ETEXI 3722 3723DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3724 "-prom-env variable=value\n" 3725 " set OpenBIOS nvram variables\n", 3726 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3727STEXI 3728@item -prom-env @var{variable}=@var{value} 3729@findex -prom-env 3730Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3731ETEXI 3732DEF("semihosting", 0, QEMU_OPTION_semihosting, 3733 "-semihosting semihosting mode\n", 3734 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3735 QEMU_ARCH_MIPS) 3736STEXI 3737@item -semihosting 3738@findex -semihosting 3739Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3740ETEXI 3741DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3742 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3743 " semihosting configuration\n", 3744QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3745QEMU_ARCH_MIPS) 3746STEXI 3747@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3748@findex -semihosting-config 3749Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3750@table @option 3751@item target=@code{native|gdb|auto} 3752Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3753or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3754during debug sessions and @code{native} otherwise. 3755@item arg=@var{str1},arg=@var{str2},... 3756Allows the user to pass input arguments, and can be used multiple times to build 3757up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3758command line is still supported for backward compatibility. If both the 3759@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3760specified, the former is passed to semihosting as it always takes precedence. 3761@end table 3762ETEXI 3763DEF("old-param", 0, QEMU_OPTION_old_param, 3764 "-old-param old param mode\n", QEMU_ARCH_ARM) 3765STEXI 3766@item -old-param 3767@findex -old-param (ARM) 3768Old param mode (ARM only). 3769ETEXI 3770 3771DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3772 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \ 3773 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \ 3774 " Enable seccomp mode 2 system call filter (default 'off').\n" \ 3775 " use 'obsolete' to allow obsolete system calls that are provided\n" \ 3776 " by the kernel, but typically no longer used by modern\n" \ 3777 " C library implementations.\n" \ 3778 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \ 3779 " its privileges by blacklisting all set*uid|gid system calls.\n" \ 3780 " The value 'children' will deny set*uid|gid system calls for\n" \ 3781 " main QEMU process but will allow forks and execves to run unprivileged\n" \ 3782 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \ 3783 " blacklisting *fork and execve\n" \ 3784 " use 'resourcecontrol' to disable process affinity and schedular priority\n", 3785 QEMU_ARCH_ALL) 3786STEXI 3787@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}] 3788@findex -sandbox 3789Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3790disable it. The default is 'off'. 3791@table @option 3792@item obsolete=@var{string} 3793Enable Obsolete system calls 3794@item elevateprivileges=@var{string} 3795Disable set*uid|gid system calls 3796@item spawn=@var{string} 3797Disable *fork and execve 3798@item resourcecontrol=@var{string} 3799Disable process affinity and schedular priority 3800@end table 3801ETEXI 3802 3803DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3804 "-readconfig <file>\n", QEMU_ARCH_ALL) 3805STEXI 3806@item -readconfig @var{file} 3807@findex -readconfig 3808Read device configuration from @var{file}. This approach is useful when you want to spawn 3809QEMU process with many command line options but you don't want to exceed the command line 3810character limit. 3811ETEXI 3812DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3813 "-writeconfig <file>\n" 3814 " read/write config file\n", QEMU_ARCH_ALL) 3815STEXI 3816@item -writeconfig @var{file} 3817@findex -writeconfig 3818Write device configuration to @var{file}. The @var{file} can be either filename to save 3819command line and device configuration into file or dash @code{-}) character to print the 3820output to stdout. This can be later used as input file for @code{-readconfig} option. 3821ETEXI 3822 3823DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3824 "-no-user-config\n" 3825 " do not load default user-provided config files at startup\n", 3826 QEMU_ARCH_ALL) 3827STEXI 3828@item -no-user-config 3829@findex -no-user-config 3830The @code{-no-user-config} option makes QEMU not load any of the user-provided 3831config files on @var{sysconfdir}. 3832ETEXI 3833 3834DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3835 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3836 " specify tracing options\n", 3837 QEMU_ARCH_ALL) 3838STEXI 3839HXCOMM This line is not accurate, as some sub-options are backend-specific but 3840HXCOMM HX does not support conditional compilation of text. 3841@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 3842@findex -trace 3843@include qemu-option-trace.texi 3844ETEXI 3845 3846HXCOMM Internal use 3847DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3848DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3849 3850#ifdef __linux__ 3851DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3852 "-enable-fips enable FIPS 140-2 compliance\n", 3853 QEMU_ARCH_ALL) 3854#endif 3855STEXI 3856@item -enable-fips 3857@findex -enable-fips 3858Enable FIPS 140-2 compliance mode. 3859ETEXI 3860 3861HXCOMM Deprecated by -machine accel=tcg property 3862DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3863 3864DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3865 "-msg timestamp[=on|off]\n" 3866 " change the format of messages\n" 3867 " on|off controls leading timestamps (default:on)\n", 3868 QEMU_ARCH_ALL) 3869STEXI 3870@item -msg timestamp[=on|off] 3871@findex -msg 3872prepend a timestamp to each log message.(default:on) 3873ETEXI 3874 3875DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3876 "-dump-vmstate <file>\n" 3877 " Output vmstate information in JSON format to file.\n" 3878 " Use the scripts/vmstate-static-checker.py file to\n" 3879 " check for possible regressions in migration code\n" 3880 " by comparing two such vmstate dumps.\n", 3881 QEMU_ARCH_ALL) 3882STEXI 3883@item -dump-vmstate @var{file} 3884@findex -dump-vmstate 3885Dump json-encoded vmstate information for current machine type to file 3886in @var{file} 3887ETEXI 3888 3889DEF("enable-sync-profile", 0, QEMU_OPTION_enable_sync_profile, 3890 "-enable-sync-profile\n" 3891 " enable synchronization profiling\n", 3892 QEMU_ARCH_ALL) 3893STEXI 3894@item -enable-sync-profile 3895@findex -enable-sync-profile 3896Enable synchronization profiling. 3897ETEXI 3898 3899STEXI 3900@end table 3901ETEXI 3902DEFHEADING() 3903 3904DEFHEADING(Generic object creation:) 3905STEXI 3906@table @option 3907ETEXI 3908 3909DEF("object", HAS_ARG, QEMU_OPTION_object, 3910 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3911 " create a new object of type TYPENAME setting properties\n" 3912 " in the order they are specified. Note that the 'id'\n" 3913 " property must be set. These objects are placed in the\n" 3914 " '/objects' path.\n", 3915 QEMU_ARCH_ALL) 3916STEXI 3917@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3918@findex -object 3919Create a new object of type @var{typename} setting properties 3920in the order they are specified. Note that the 'id' 3921property must be set. These objects are placed in the 3922'/objects' path. 3923 3924@table @option 3925 3926@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} 3927 3928Creates a memory file backend object, which can be used to back 3929the guest RAM with huge pages. 3930 3931The @option{id} parameter is a unique ID that will be used to reference this 3932memory region when configuring the @option{-numa} argument. 3933 3934The @option{size} option provides the size of the memory region, and accepts 3935common suffixes, eg @option{500M}. 3936 3937The @option{mem-path} provides the path to either a shared memory or huge page 3938filesystem mount. 3939 3940The @option{share} boolean option determines whether the memory 3941region is marked as private to QEMU, or shared. The latter allows 3942a co-operating external process to access the QEMU memory region. 3943 3944The @option{share} is also required for pvrdma devices due to 3945limitations in the RDMA API provided by Linux. 3946 3947Setting share=on might affect the ability to configure NUMA 3948bindings for the memory backend under some circumstances, see 3949Documentation/vm/numa_memory_policy.txt on the Linux kernel 3950source tree for additional details. 3951 3952Setting the @option{discard-data} boolean option to @var{on} 3953indicates that file contents can be destroyed when QEMU exits, 3954to avoid unnecessarily flushing data to the backing file. Note 3955that @option{discard-data} is only an optimization, and QEMU 3956might not discard file contents if it aborts unexpectedly or is 3957terminated using SIGKILL. 3958 3959The @option{merge} boolean option enables memory merge, also known as 3960MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for 3961memory deduplication. 3962 3963Setting the @option{dump} boolean option to @var{off} excludes the memory from 3964core dumps. This feature is also known as MADV_DONTDUMP. 3965 3966The @option{prealloc} boolean option enables memory preallocation. 3967 3968The @option{host-nodes} option binds the memory range to a list of NUMA host 3969nodes. 3970 3971The @option{policy} option sets the NUMA policy to one of the following values: 3972 3973@table @option 3974@item @var{default} 3975default host policy 3976 3977@item @var{preferred} 3978prefer the given host node list for allocation 3979 3980@item @var{bind} 3981restrict memory allocation to the given host node list 3982 3983@item @var{interleave} 3984interleave memory allocations across the given host node list 3985@end table 3986 3987The @option{align} option specifies the base address alignment when 3988QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg 3989@option{2M}. Some backend store specified by @option{mem-path} 3990requires an alignment different than the default one used by QEMU, eg 3991the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In 3992such cases, users can specify the required alignment via this option. 3993 3994The @option{pmem} option specifies whether the backing file specified 3995by @option{mem-path} is in host persistent memory that can be accessed 3996using the SNIA NVM programming model (e.g. Intel NVDIMM). 3997If @option{pmem} is set to 'on', QEMU will take necessary operations to 3998guarantee the persistence of its own writes to @option{mem-path} 3999(e.g. in vNVDIMM label emulation and live migration). 4000 4001@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} 4002 4003Creates a memory backend object, which can be used to back the guest RAM. 4004Memory backend objects offer more control than the @option{-m} option that is 4005traditionally used to define guest RAM. Please refer to 4006@option{memory-backend-file} for a description of the options. 4007 4008@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} 4009 4010Creates an anonymous memory file backend object, which allows QEMU to 4011share the memory with an external process (e.g. when using 4012vhost-user). The memory is allocated with memfd and optional 4013sealing. (Linux only) 4014 4015The @option{seal} option creates a sealed-file, that will block 4016further resizing the memory ('on' by default). 4017 4018The @option{hugetlb} option specify the file to be created resides in 4019the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with 4020the @option{hugetlb} option, the @option{hugetlbsize} option specify 4021the hugetlb page size on systems that support multiple hugetlb page 4022sizes (it must be a power of 2 value supported by the system). 4023 4024In some versions of Linux, the @option{hugetlb} option is incompatible 4025with the @option{seal} option (requires at least Linux 4.16). 4026 4027Please refer to @option{memory-backend-file} for a description of the 4028other options. 4029 4030@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4031 4032Creates a random number generator backend which obtains entropy from 4033a device on the host. The @option{id} parameter is a unique ID that 4034will be used to reference this entropy backend from the @option{virtio-rng} 4035device. The @option{filename} parameter specifies which file to obtain 4036entropy from and if omitted defaults to @option{/dev/random}. 4037 4038@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4039 4040Creates a random number generator backend which obtains entropy from 4041an external daemon running on the host. The @option{id} parameter is 4042a unique ID that will be used to reference this entropy backend from 4043the @option{virtio-rng} device. The @option{chardev} parameter is 4044the unique ID of a character device backend that provides the connection 4045to the RNG daemon. 4046 4047@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4048 4049Creates a TLS anonymous credentials object, which can be used to provide 4050TLS support on network backends. The @option{id} parameter is a unique 4051ID which network backends will use to access the credentials. The 4052@option{endpoint} is either @option{server} or @option{client} depending 4053on whether the QEMU network backend that uses the credentials will be 4054acting as a client or as a server. If @option{verify-peer} is enabled 4055(the default) then once the handshake is completed, the peer credentials 4056will be verified, though this is a no-op for anonymous credentials. 4057 4058The @var{dir} parameter tells QEMU where to find the credential 4059files. For server endpoints, this directory may contain a file 4060@var{dh-params.pem} providing diffie-hellman parameters to use 4061for the TLS server. If the file is missing, QEMU will generate 4062a set of DH parameters at startup. This is a computationally 4063expensive operation that consumes random pool entropy, so it is 4064recommended that a persistent set of parameters be generated 4065upfront and saved. 4066 4067@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] 4068 4069Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide 4070TLS support on network backends. The @option{id} parameter is a unique 4071ID which network backends will use to access the credentials. The 4072@option{endpoint} is either @option{server} or @option{client} depending 4073on whether the QEMU network backend that uses the credentials will be 4074acting as a client or as a server. For clients only, @option{username} 4075is the username which will be sent to the server. If omitted 4076it defaults to ``qemu''. 4077 4078The @var{dir} parameter tells QEMU where to find the keys file. 4079It is called ``@var{dir}/keys.psk'' and contains ``username:key'' 4080pairs. This file can most easily be created using the GnuTLS 4081@code{psktool} program. 4082 4083For server endpoints, @var{dir} may also 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 4089up front and saved. 4090 4091@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} 4092 4093Creates a TLS anonymous 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. If @option{verify-peer} is enabled 4099(the default) then once the handshake is completed, the peer credentials 4100will be verified. With x509 certificates, this implies that the clients 4101must be provided with valid client certificates too. 4102 4103The @var{dir} parameter tells QEMU where to find the credential 4104files. For server endpoints, this directory may contain a file 4105@var{dh-params.pem} providing diffie-hellman parameters to use 4106for the TLS server. If the file is missing, QEMU will generate 4107a set of DH parameters at startup. This is a computationally 4108expensive operation that consumes random pool entropy, so it is 4109recommended that a persistent set of parameters be generated 4110upfront and saved. 4111 4112For x509 certificate credentials the directory will contain further files 4113providing the x509 certificates. The certificates must be stored 4114in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4115@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4116@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4117 4118For the @var{server-key.pem} and @var{client-key.pem} files which 4119contain sensitive private keys, it is possible to use an encrypted 4120version by providing the @var{passwordid} parameter. This provides 4121the ID of a previously created @code{secret} object containing the 4122password for decryption. 4123 4124The @var{priority} parameter allows to override the global default 4125priority used by gnutls. This can be useful if the system administrator 4126needs to use a weaker set of crypto priorities for QEMU without 4127potentially forcing the weakness onto all applications. Or conversely 4128if one wants wants a stronger default for QEMU than for all other 4129applications, they can do this through this parameter. Its format is 4130a gnutls priority string as described at 4131@url{https://gnutls.org/manual/html_node/Priority-Strings.html}. 4132 4133@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4134 4135Interval @var{t} can't be 0, this filter batches the packet delivery: all 4136packets arriving in a given interval on netdev @var{netdevid} are delayed 4137until the end of the interval. Interval is in microseconds. 4138@option{status} is optional that indicate whether the netfilter is 4139on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4140 4141queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4142 4143@option{all}: the filter is attached both to the receive and the transmit 4144 queue of the netdev (default). 4145 4146@option{rx}: the filter is attached to the receive queue of the netdev, 4147 where it will receive packets sent to the netdev. 4148 4149@option{tx}: the filter is attached to the transmit queue of the netdev, 4150 where it will receive packets sent by the netdev. 4151 4152@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4153 4154filter-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. 4155 4156@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4157 4158filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4159@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag, 4160filter-redirector will redirect packet with vnet_hdr_len. 4161Create a filter-redirector we need to differ outdev id from indev id, id can not 4162be the same. we can just use indev or outdev, but at least one of indev or outdev 4163need to be specified. 4164 4165@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support] 4166 4167Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4168secondary from primary to keep secondary tcp connection,and rewrite 4169tcp packet to primary from secondary make tcp packet can be handled by 4170client.if it has the vnet_hdr_support flag, we can parse packet with vnet header. 4171 4172usage: 4173colo secondary: 4174-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4175-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4176-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4177 4178@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4179 4180Dump the network traffic on netdev @var{dev} to the file specified by 4181@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4182The file format is libpcap, so it can be analyzed with tools such as tcpdump 4183or Wireshark. 4184 4185@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support] 4186 4187Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4188secondary packet. If the packets are same, we will output primary 4189packet to outdev@var{chardevid}, else we will notify colo-frame 4190do checkpoint and send primary packet to outdev@var{chardevid}. 4191if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len. 4192 4193we must use it with the help of filter-mirror and filter-redirector. 4194 4195@example 4196 4197primary: 4198-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4199-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4200-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4201-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4202-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4203-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4204-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4205-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4206-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4207-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4208-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4209-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4210 4211secondary: 4212-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4213-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4214-chardev socket,id=red0,host=3.3.3.3,port=9003 4215-chardev socket,id=red1,host=3.3.3.3,port=9004 4216-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4217-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4218 4219@end example 4220 4221If you want to know the detail of above command line, you can read 4222the colo-compare git log. 4223 4224@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4225 4226Creates a cryptodev backend which executes crypto opreation from 4227the QEMU cipher APIS. The @var{id} parameter is 4228a unique ID that will be used to reference this cryptodev backend from 4229the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4230which specify the queue number of cryptodev backend, the default of 4231@var{queues} is 1. 4232 4233@example 4234 4235 # qemu-system-x86_64 \ 4236 [...] \ 4237 -object cryptodev-backend-builtin,id=cryptodev0 \ 4238 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4239 [...] 4240@end example 4241 4242@item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}] 4243 4244Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}. 4245The @var{id} parameter is a unique ID that will be used to reference this 4246cryptodev backend from the @option{virtio-crypto} device. 4247The chardev should be a unix domain socket backed one. The vhost-user uses 4248a specifically defined protocol to pass vhost ioctl replacement messages 4249to an application on the other end of the socket. 4250The @var{queues} parameter is optional, which specify the queue number 4251of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1. 4252 4253@example 4254 4255 # qemu-system-x86_64 \ 4256 [...] \ 4257 -chardev socket,id=chardev0,path=/path/to/socket \ 4258 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \ 4259 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4260 [...] 4261@end example 4262 4263@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4264@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4265 4266Defines a secret to store a password, encryption key, or some other sensitive 4267data. The sensitive data can either be passed directly via the @var{data} 4268parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4269parameter is insecure unless the sensitive data is encrypted. 4270 4271The sensitive data can be provided in raw format (the default), or base64. 4272When encoded as JSON, the raw format only supports valid UTF-8 characters, 4273so base64 is recommended for sending binary data. QEMU will convert from 4274which ever format is provided to the format it needs internally. eg, an 4275RBD password can be provided in raw format, even though it will be base64 4276encoded when passed onto the RBD sever. 4277 4278For added protection, it is possible to encrypt the data associated with 4279a secret using the AES-256-CBC cipher. Use of encryption is indicated 4280by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4281parameter provides the ID of a previously defined secret that contains 4282the AES-256 decryption key. This key should be 32-bytes long and be 4283base64 encoded. The @var{iv} parameter provides the random initialization 4284vector used for encryption of this particular secret and should be a 4285base64 encrypted string of the 16-byte IV. 4286 4287The simplest (insecure) usage is to provide the secret inline 4288 4289@example 4290 4291 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4292 4293@end example 4294 4295The simplest secure usage is to provide the secret via a file 4296 4297 # printf "letmein" > mypasswd.txt 4298 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4299 4300For greater security, AES-256-CBC should be used. To illustrate usage, 4301consider the openssl command line tool which can encrypt the data. Note 4302that when encrypting, the plaintext must be padded to the cipher block 4303size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4304 4305First a master key needs to be created in base64 encoding: 4306 4307@example 4308 # openssl rand -base64 32 > key.b64 4309 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4310@end example 4311 4312Each secret to be encrypted needs to have a random initialization vector 4313generated. These do not need to be kept secret 4314 4315@example 4316 # openssl rand -base64 16 > iv.b64 4317 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4318@end example 4319 4320The secret to be defined can now be encrypted, in this case we're 4321telling openssl to base64 encode the result, but it could be left 4322as raw bytes if desired. 4323 4324@example 4325 # SECRET=$(printf "letmein" | 4326 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4327@end example 4328 4329When launching QEMU, create a master secret pointing to @code{key.b64} 4330and specify that to be used to decrypt the user password. Pass the 4331contents of @code{iv.b64} to the second secret 4332 4333@example 4334 # $QEMU \ 4335 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4336 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4337 data=$SECRET,iv=$(<iv.b64) 4338@end example 4339 4340@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}] 4341 4342Create a Secure Encrypted Virtualization (SEV) guest object, which can be used 4343to provide the guest memory encryption support on AMD processors. 4344 4345When memory encryption is enabled, one of the physical address bit (aka the 4346C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos} 4347is used to provide the C-bit position. The C-bit position is Host family dependent 4348hence user must provide this value. On EPYC, the value should be 47. 4349 4350When memory encryption is enabled, we loose certain bits in physical address space. 4351The @option{reduced-phys-bits} is used to provide the number of bits we loose in 4352physical address space. Similar to C-bit, the value is Host family dependent. 4353On EPYC, the value should be 5. 4354 4355The @option{sev-device} provides the device file to use for communicating with 4356the SEV firmware running inside AMD Secure Processor. The default device is 4357'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are 4358created by CCP driver. 4359 4360The @option{policy} provides the guest policy to be enforced by the SEV firmware 4361and restrict what configuration and operational commands can be performed on this 4362guest by the hypervisor. The policy should be provided by the guest owner and is 4363bound to the guest and cannot be changed throughout the lifetime of the guest. 4364The default is 0. 4365 4366If guest @option{policy} allows sharing the key with another SEV guest then 4367@option{handle} can be use to provide handle of the guest from which to share 4368the key. 4369 4370The @option{dh-cert-file} and @option{session-file} provides the guest owner's 4371Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters 4372are used for establishing a cryptographic session with the guest owner to 4373negotiate keys used for attestation. The file must be encoded in base64. 4374 4375e.g to launch a SEV guest 4376@example 4377 # $QEMU \ 4378 ...... 4379 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ 4380 -machine ...,memory-encryption=sev0 4381 ..... 4382 4383@end example 4384@end table 4385 4386ETEXI 4387 4388 4389HXCOMM This is the last statement. Insert new options before this line! 4390STEXI 4391@end table 4392ETEXI 4393
