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][,tftp-server-name=name][,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 tftp-server-name=@var{name} 2064In BOOTP reply, broadcast @var{name} as the "TFTP server name" (RFC2132 option 206566). This can be used to advise the guest to load boot files or configurations 2066from a different server than the host address. 2067 2068@item bootfile=@var{file} 2069When using the user mode network stack, broadcast @var{file} as the BOOTP 2070filename. In conjunction with @option{tftp}, this can be used to network boot 2071a guest from a local directory. 2072 2073Example (using pxelinux): 2074@example 2075qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \ 2076 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2077@end example 2078 2079@item smb=@var{dir}[,smbserver=@var{addr}] 2080When using the user mode network stack, activate a built-in SMB 2081server so that Windows OSes can access to the host files in @file{@var{dir}} 2082transparently. The IP address of the SMB server can be set to @var{addr}. By 2083default the 4th IP in the guest network is used, i.e. x.x.x.4. 2084 2085In the guest Windows OS, the line: 2086@example 208710.0.2.4 smbserver 2088@end example 2089must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2090or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2091 2092Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2093 2094Note that a SAMBA server must be installed on the host OS. 2095 2096@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2097Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2098the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2099@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2100given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2101be bound to a specific host interface. If no connection type is set, TCP is 2102used. This option can be given multiple times. 2103 2104For example, to redirect host X11 connection from screen 1 to guest 2105screen 0, use the following: 2106 2107@example 2108# on the host 2109qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 2110# this host xterm should open in the guest X11 server 2111xterm -display :1 2112@end example 2113 2114To redirect telnet connections from host port 5555 to telnet port on 2115the guest, use the following: 2116 2117@example 2118# on the host 2119qemu-system-i386 -nic user,hostfwd=tcp::5555-:23 2120telnet localhost 5555 2121@end example 2122 2123Then when you use on the host @code{telnet localhost 5555}, you 2124connect to the guest telnet server. 2125 2126@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2127@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2128Forward guest TCP connections to the IP address @var{server} on port @var{port} 2129to the character device @var{dev} or to a program executed by @var{cmd:command} 2130which gets spawned for each connection. This option can be given multiple times. 2131 2132You can either use a chardev directly and have that one used throughout QEMU's 2133lifetime, like in the following example: 2134 2135@example 2136# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2137# the guest accesses it 2138qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 2139@end example 2140 2141Or you can execute a command on every TCP connection established by the guest, 2142so that QEMU behaves similar to an inetd process for that virtual server: 2143 2144@example 2145# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2146# and connect the TCP stream to its stdin/stdout 2147qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2148@end example 2149 2150@end table 2151 2152@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2153Configure a host TAP network backend with ID @var{id}. 2154 2155Use the network script @var{file} to configure it and the network script 2156@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2157automatically provides one. The default network configure script is 2158@file{/etc/qemu-ifup} and the default network deconfigure script is 2159@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2160to disable script execution. 2161 2162If running QEMU as an unprivileged user, use the network helper 2163@var{helper} to configure the TAP interface and attach it to the bridge. 2164The default network helper executable is @file{/path/to/qemu-bridge-helper} 2165and the default bridge device is @file{br0}. 2166 2167@option{fd}=@var{h} can be used to specify the handle of an already 2168opened host TAP interface. 2169 2170Examples: 2171 2172@example 2173#launch a QEMU instance with the default network script 2174qemu-system-i386 linux.img -nic tap 2175@end example 2176 2177@example 2178#launch a QEMU instance with two NICs, each one connected 2179#to a TAP device 2180qemu-system-i386 linux.img \ 2181 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \ 2182 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1 2183@end example 2184 2185@example 2186#launch a QEMU instance with the default network helper to 2187#connect a TAP device to bridge br0 2188qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \ 2189 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper" 2190@end example 2191 2192@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2193Connect a host TAP network interface to a host bridge device. 2194 2195Use the network helper @var{helper} to configure the TAP interface and 2196attach it to the bridge. The default network helper executable is 2197@file{/path/to/qemu-bridge-helper} and the default bridge 2198device is @file{br0}. 2199 2200Examples: 2201 2202@example 2203#launch a QEMU instance with the default network helper to 2204#connect a TAP device to bridge br0 2205qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1 2206@end example 2207 2208@example 2209#launch a QEMU instance with the default network helper to 2210#connect a TAP device to bridge qemubr0 2211qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1 2212@end example 2213 2214@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2215 2216This host network backend can be used to connect the guest's network to 2217another QEMU virtual machine using a TCP socket connection. If @option{listen} 2218is specified, QEMU waits for incoming connections on @var{port} 2219(@var{host} is optional). @option{connect} is used to connect to 2220another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2221specifies an already opened TCP socket. 2222 2223Example: 2224@example 2225# launch a first QEMU instance 2226qemu-system-i386 linux.img \ 2227 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2228 -netdev socket,id=n1,listen=:1234 2229# connect the network of this instance to the network of the first instance 2230qemu-system-i386 linux.img \ 2231 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2232 -netdev socket,id=n2,connect=127.0.0.1:1234 2233@end example 2234 2235@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2236 2237Configure a socket host network backend to share the guest's network traffic 2238with another QEMU virtual machines using a UDP multicast socket, effectively 2239making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. 2240NOTES: 2241@enumerate 2242@item 2243Several QEMU can be running on different hosts and share same bus (assuming 2244correct multicast setup for these hosts). 2245@item 2246mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2247@url{http://user-mode-linux.sf.net}. 2248@item 2249Use @option{fd=h} to specify an already opened UDP multicast socket. 2250@end enumerate 2251 2252Example: 2253@example 2254# launch one QEMU instance 2255qemu-system-i386 linux.img \ 2256 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2257 -netdev socket,id=n1,mcast=230.0.0.1:1234 2258# launch another QEMU instance on same "bus" 2259qemu-system-i386 linux.img \ 2260 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2261 -netdev socket,id=n2,mcast=230.0.0.1:1234 2262# launch yet another QEMU instance on same "bus" 2263qemu-system-i386 linux.img \ 2264 -device e1000,netdev=n3,mac=52:54:00:12:34:58 \ 2265 -netdev socket,id=n3,mcast=230.0.0.1:1234 2266@end example 2267 2268Example (User Mode Linux compat.): 2269@example 2270# launch QEMU instance (note mcast address selected is UML's default) 2271qemu-system-i386 linux.img \ 2272 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2273 -netdev socket,id=n1,mcast=239.192.168.1:1102 2274# launch UML 2275/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2276@end example 2277 2278Example (send packets from host's 1.2.3.4): 2279@example 2280qemu-system-i386 linux.img \ 2281 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2282 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2283@end example 2284 2285@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}] 2286Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a 2287popular protocol to transport Ethernet (and other Layer 2) data frames between 2288two systems. It is present in routers, firewalls and the Linux kernel 2289(from version 3.3 onwards). 2290 2291This transport allows a VM to communicate to another VM, router or firewall directly. 2292 2293@table @option 2294@item src=@var{srcaddr} 2295 source address (mandatory) 2296@item dst=@var{dstaddr} 2297 destination address (mandatory) 2298@item udp 2299 select udp encapsulation (default is ip). 2300@item srcport=@var{srcport} 2301 source udp port. 2302@item dstport=@var{dstport} 2303 destination udp port. 2304@item ipv6 2305 force v6, otherwise defaults to v4. 2306@item rxcookie=@var{rxcookie} 2307@itemx txcookie=@var{txcookie} 2308 Cookies are a weak form of security in the l2tpv3 specification. 2309Their function is mostly to prevent misconfiguration. By default they are 32 2310bit. 2311@item cookie64 2312 Set cookie size to 64 bit instead of the default 32 2313@item counter=off 2314 Force a 'cut-down' L2TPv3 with no counter as in 2315draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2316@item pincounter=on 2317 Work around broken counter handling in peer. This may also help on 2318networks which have packet reorder. 2319@item offset=@var{offset} 2320 Add an extra offset between header and data 2321@end table 2322 2323For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2324on the remote Linux host 1.2.3.4: 2325@example 2326# Setup tunnel on linux host using raw ip as encapsulation 2327# on 1.2.3.4 2328ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2329 encap udp udp_sport 16384 udp_dport 16384 2330ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2331 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2332ifconfig vmtunnel0 mtu 1500 2333ifconfig vmtunnel0 up 2334brctl addif br-lan vmtunnel0 2335 2336 2337# on 4.3.2.1 2338# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2339 2340qemu-system-i386 linux.img -device e1000,netdev=n1 \ 2341 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2342 2343@end example 2344 2345@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2346Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and 2347listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2348and MODE @var{octalmode} to change default ownership and permissions for 2349communication port. This option is only available if QEMU has been compiled 2350with vde support enabled. 2351 2352Example: 2353@example 2354# launch vde switch 2355vde_switch -F -sock /tmp/myswitch 2356# launch QEMU instance 2357qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch 2358@end example 2359 2360@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2361 2362Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2363be a unix domain socket backed one. The vhost-user uses a specifically defined 2364protocol to pass vhost ioctl replacement messages to an application on the other 2365end of the socket. On non-MSIX guests, the feature can be forced with 2366@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2367be created for multiqueue vhost-user. 2368 2369Example: 2370@example 2371qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2372 -numa node,memdev=mem \ 2373 -chardev socket,id=chr0,path=/path/to/socket \ 2374 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2375 -device virtio-net-pci,netdev=net0 2376@end example 2377 2378@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}] 2379 2380Create a hub port on the emulated hub with ID @var{hubid}. 2381 2382The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a 2383single netdev. Alternatively, you can also connect the hubport to another 2384netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option. 2385 2386@item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2387@findex -net 2388Legacy option to configure or create an on-board (or machine default) Network 2389Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. 2390the default hub), or to the netdev @var{nd}. 2391The NIC is an e1000 by default on the PC target. Optionally, the MAC address 2392can be changed to @var{mac}, the device address set to @var{addr} (PCI cards 2393only), and a @var{name} can be assigned for use in monitor commands. 2394Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2395that the card should have; this option currently only affects virtio cards; set 2396@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2397NIC is created. QEMU can emulate several different models of network card. 2398Use @code{-net nic,model=help} for a list of available devices for your target. 2399 2400@item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}] 2401Configure a host network backend (with the options corresponding to the same 2402@option{-netdev} option) and connect it to the emulated hub 0 (the default 2403hub). Use @var{name} to specify the name of the hub port. 2404ETEXI 2405 2406STEXI 2407@end table 2408ETEXI 2409DEFHEADING() 2410 2411DEFHEADING(Character device options:) 2412 2413DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2414 "-chardev help\n" 2415 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2416 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2417 " [,server][,nowait][,telnet][,websocket][,reconnect=seconds][,mux=on|off]\n" 2418 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2419 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,websocket][,reconnect=seconds]\n" 2420 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2421 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2422 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2423 " [,logfile=PATH][,logappend=on|off]\n" 2424 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2425 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2426 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2427 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2428 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2429 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2430#ifdef _WIN32 2431 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2432 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2433#else 2434 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2435 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2436#endif 2437#ifdef CONFIG_BRLAPI 2438 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2439#endif 2440#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2441 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2442 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2443 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2444#endif 2445#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2446 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2447 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2448#endif 2449#if defined(CONFIG_SPICE) 2450 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2451 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2452#endif 2453 , QEMU_ARCH_ALL 2454) 2455 2456STEXI 2457 2458The general form of a character device option is: 2459@table @option 2460@item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}] 2461@findex -chardev 2462Backend is one of: 2463@option{null}, 2464@option{socket}, 2465@option{udp}, 2466@option{msmouse}, 2467@option{vc}, 2468@option{ringbuf}, 2469@option{file}, 2470@option{pipe}, 2471@option{console}, 2472@option{serial}, 2473@option{pty}, 2474@option{stdio}, 2475@option{braille}, 2476@option{tty}, 2477@option{parallel}, 2478@option{parport}, 2479@option{spicevmc}, 2480@option{spiceport}. 2481The specific backend will determine the applicable options. 2482 2483Use @code{-chardev help} to print all available chardev backend types. 2484 2485All devices must have an id, which can be any string up to 127 characters long. 2486It is used to uniquely identify this device in other command line directives. 2487 2488A character device may be used in multiplexing mode by multiple front-ends. 2489Specify @option{mux=on} to enable this mode. 2490A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2491backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2492If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2493create a multiplexer with your specified ID, and you can then configure multiple 2494front ends to use that chardev ID for their input/output. Up to four different 2495front ends can be connected to a single multiplexed chardev. (Without 2496multiplexing enabled, a chardev can only be used by a single front end.) 2497For instance you could use this to allow a single stdio chardev to be used by 2498two serial ports and the QEMU monitor: 2499 2500@example 2501-chardev stdio,mux=on,id=char0 \ 2502-mon chardev=char0,mode=readline \ 2503-serial chardev:char0 \ 2504-serial chardev:char0 2505@end example 2506 2507You can have more than one multiplexer in a system configuration; for instance 2508you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2509multiplexed between the QEMU monitor and a parallel port: 2510 2511@example 2512-chardev stdio,mux=on,id=char0 \ 2513-mon chardev=char0,mode=readline \ 2514-parallel chardev:char0 \ 2515-chardev tcp,...,mux=on,id=char1 \ 2516-serial chardev:char1 \ 2517-serial chardev:char1 2518@end example 2519 2520When you're using a multiplexed character device, some escape sequences are 2521interpreted in the input. @xref{mux_keys, Keys in the character backend 2522multiplexer}. 2523 2524Note that some other command line options may implicitly create multiplexed 2525character backends; for instance @option{-serial mon:stdio} creates a 2526multiplexed stdio backend connected to the serial port and the QEMU monitor, 2527and @option{-nographic} also multiplexes the console and the monitor to 2528stdio. 2529 2530There is currently no support for multiplexing in the other direction 2531(where a single QEMU front end takes input and output from multiple chardevs). 2532 2533Every backend supports the @option{logfile} option, which supplies the path 2534to a file to record all data transmitted via the backend. The @option{logappend} 2535option controls whether the log file will be truncated or appended to when 2536opened. 2537 2538@end table 2539 2540The available backends are: 2541 2542@table @option 2543@item -chardev null,id=@var{id} 2544A void device. This device will not emit any data, and will drop any data it 2545receives. The null backend does not take any options. 2546 2547@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,websocket][,reconnect=@var{seconds}][,tls-creds=@var{id}] 2548 2549Create a two-way stream socket, which can be either a TCP or a unix socket. A 2550unix socket will be created if @option{path} is specified. Behaviour is 2551undefined if TCP options are specified for a unix socket. 2552 2553@option{server} specifies that the socket shall be a listening socket. 2554 2555@option{nowait} specifies that QEMU should not block waiting for a client to 2556connect to a listening socket. 2557 2558@option{telnet} specifies that traffic on the socket should interpret telnet 2559escape sequences. 2560 2561@option{websocket} specifies that the socket uses WebSocket protocol for 2562communication. 2563 2564@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2565the remote end goes away. qemu will delay this many seconds and then attempt 2566to reconnect. Zero disables reconnecting, and is the default. 2567 2568@option{tls-creds} requests enablement of the TLS protocol for encryption, 2569and specifies the id of the TLS credentials to use for the handshake. The 2570credentials must be previously created with the @option{-object tls-creds} 2571argument. 2572 2573TCP and unix socket options are given below: 2574 2575@table @option 2576 2577@item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay] 2578 2579@option{host} for a listening socket specifies the local address to be bound. 2580For a connecting socket species the remote host to connect to. @option{host} is 2581optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2582 2583@option{port} for a listening socket specifies the local port to be bound. For a 2584connecting socket specifies the port on the remote host to connect to. 2585@option{port} can be given as either a port number or a service name. 2586@option{port} is required. 2587 2588@option{to} is only relevant to listening sockets. If it is specified, and 2589@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2590to and including @option{to} until it succeeds. @option{to} must be specified 2591as a port number. 2592 2593@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2594If neither is specified the socket may use either protocol. 2595 2596@option{nodelay} disables the Nagle algorithm. 2597 2598@item unix options: path=@var{path} 2599 2600@option{path} specifies the local path of the unix socket. @option{path} is 2601required. 2602 2603@end table 2604 2605@item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6] 2606 2607Sends all traffic from the guest to a remote host over UDP. 2608 2609@option{host} specifies the remote host to connect to. If not specified it 2610defaults to @code{localhost}. 2611 2612@option{port} specifies the port on the remote host to connect to. @option{port} 2613is required. 2614 2615@option{localaddr} specifies the local address to bind to. If not specified it 2616defaults to @code{0.0.0.0}. 2617 2618@option{localport} specifies the local port to bind to. If not specified any 2619available local port will be used. 2620 2621@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2622If neither is specified the device may use either protocol. 2623 2624@item -chardev msmouse,id=@var{id} 2625 2626Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2627take any options. 2628 2629@item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]] 2630 2631Connect to a QEMU text console. @option{vc} may optionally be given a specific 2632size. 2633 2634@option{width} and @option{height} specify the width and height respectively of 2635the console, in pixels. 2636 2637@option{cols} and @option{rows} specify that the console be sized to fit a text 2638console with the given dimensions. 2639 2640@item -chardev ringbuf,id=@var{id}[,size=@var{size}] 2641 2642Create a ring buffer with fixed size @option{size}. 2643@var{size} must be a power of two and defaults to @code{64K}. 2644 2645@item -chardev file,id=@var{id},path=@var{path} 2646 2647Log all traffic received from the guest to a file. 2648 2649@option{path} specifies the path of the file to be opened. This file will be 2650created if it does not already exist, and overwritten if it does. @option{path} 2651is required. 2652 2653@item -chardev pipe,id=@var{id},path=@var{path} 2654 2655Create a two-way connection to the guest. The behaviour differs slightly between 2656Windows hosts and other hosts: 2657 2658On Windows, a single duplex pipe will be created at 2659@file{\\.pipe\@option{path}}. 2660 2661On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2662@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2663received by the guest. Data written by the guest can be read from 2664@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2665be present. 2666 2667@option{path} forms part of the pipe path as described above. @option{path} is 2668required. 2669 2670@item -chardev console,id=@var{id} 2671 2672Send traffic from the guest to QEMU's standard output. @option{console} does not 2673take any options. 2674 2675@option{console} is only available on Windows hosts. 2676 2677@item -chardev serial,id=@var{id},path=@option{path} 2678 2679Send traffic from the guest to a serial device on the host. 2680 2681On Unix hosts serial will actually accept any tty device, 2682not only serial lines. 2683 2684@option{path} specifies the name of the serial device to open. 2685 2686@item -chardev pty,id=@var{id} 2687 2688Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2689not take any options. 2690 2691@option{pty} is not available on Windows hosts. 2692 2693@item -chardev stdio,id=@var{id}[,signal=on|off] 2694Connect to standard input and standard output of the QEMU process. 2695 2696@option{signal} controls if signals are enabled on the terminal, that includes 2697exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2698default, use @option{signal=off} to disable it. 2699 2700@item -chardev braille,id=@var{id} 2701 2702Connect to a local BrlAPI server. @option{braille} does not take any options. 2703 2704@item -chardev tty,id=@var{id},path=@var{path} 2705 2706@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2707DragonFlyBSD hosts. It is an alias for @option{serial}. 2708 2709@option{path} specifies the path to the tty. @option{path} is required. 2710 2711@item -chardev parallel,id=@var{id},path=@var{path} 2712@itemx -chardev parport,id=@var{id},path=@var{path} 2713 2714@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2715 2716Connect to a local parallel port. 2717 2718@option{path} specifies the path to the parallel port device. @option{path} is 2719required. 2720 2721@item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name} 2722 2723@option{spicevmc} is only available when spice support is built in. 2724 2725@option{debug} debug level for spicevmc 2726 2727@option{name} name of spice channel to connect to 2728 2729Connect to a spice virtual machine channel, such as vdiport. 2730 2731@item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name} 2732 2733@option{spiceport} is only available when spice support is built in. 2734 2735@option{debug} debug level for spicevmc 2736 2737@option{name} name of spice port to connect to 2738 2739Connect to a spice port, allowing a Spice client to handle the traffic 2740identified by a name (preferably a fqdn). 2741ETEXI 2742 2743STEXI 2744@end table 2745ETEXI 2746DEFHEADING() 2747 2748DEFHEADING(Bluetooth(R) options:) 2749STEXI 2750@table @option 2751ETEXI 2752 2753DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2754 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2755 "-bt hci,host[:id]\n" \ 2756 " use host's HCI with the given name\n" \ 2757 "-bt hci[,vlan=n]\n" \ 2758 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2759 "-bt vhci[,vlan=n]\n" \ 2760 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2761 "-bt device:dev[,vlan=n]\n" \ 2762 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2763 QEMU_ARCH_ALL) 2764STEXI 2765@item -bt hci[...] 2766@findex -bt 2767Defines the function of the corresponding Bluetooth HCI. -bt options 2768are matched with the HCIs present in the chosen machine type. For 2769example when emulating a machine with only one HCI built into it, only 2770the first @code{-bt hci[...]} option is valid and defines the HCI's 2771logic. The Transport Layer is decided by the machine type. Currently 2772the machines @code{n800} and @code{n810} have one HCI and all other 2773machines have none. 2774 2775@anchor{bt-hcis} 2776The following three types are recognized: 2777 2778@table @option 2779@item -bt hci,null 2780(default) The corresponding Bluetooth HCI assumes no internal logic 2781and will not respond to any HCI commands or emit events. 2782 2783@item -bt hci,host[:@var{id}] 2784(@code{bluez} only) The corresponding HCI passes commands / events 2785to / from the physical HCI identified by the name @var{id} (default: 2786@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2787capable systems like Linux. 2788 2789@item -bt hci[,vlan=@var{n}] 2790Add a virtual, standard HCI that will participate in the Bluetooth 2791scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2792VLANs, devices inside a bluetooth network @var{n} can only communicate 2793with other devices in the same network (scatternet). 2794@end table 2795 2796@item -bt vhci[,vlan=@var{n}] 2797(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2798to the host bluetooth stack instead of to the emulated target. This 2799allows the host and target machines to participate in a common scatternet 2800and communicate. Requires the Linux @code{vhci} driver installed. Can 2801be used as following: 2802 2803@example 2804qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2805@end example 2806 2807@item -bt device:@var{dev}[,vlan=@var{n}] 2808Emulate a bluetooth device @var{dev} and place it in network @var{n} 2809(default @code{0}). QEMU can only emulate one type of bluetooth devices 2810currently: 2811 2812@table @option 2813@item keyboard 2814Virtual wireless keyboard implementing the HIDP bluetooth profile. 2815@end table 2816ETEXI 2817 2818STEXI 2819@end table 2820ETEXI 2821DEFHEADING() 2822 2823#ifdef CONFIG_TPM 2824DEFHEADING(TPM device options:) 2825 2826DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2827 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2828 " use path to provide path to a character device; default is /dev/tpm0\n" 2829 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2830 " not provided it will be searched for in /sys/class/misc/tpm?/device\n" 2831 "-tpmdev emulator,id=id,chardev=dev\n" 2832 " configure the TPM device using chardev backend\n", 2833 QEMU_ARCH_ALL) 2834STEXI 2835 2836The general form of a TPM device option is: 2837@table @option 2838 2839@item -tpmdev @var{backend},id=@var{id}[,@var{options}] 2840@findex -tpmdev 2841 2842The specific backend type will determine the applicable options. 2843The @code{-tpmdev} option creates the TPM backend and requires a 2844@code{-device} option that specifies the TPM frontend interface model. 2845 2846Use @code{-tpmdev help} to print all available TPM backend types. 2847 2848@end table 2849 2850The available backends are: 2851 2852@table @option 2853 2854@item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path} 2855 2856(Linux-host only) Enable access to the host's TPM using the passthrough 2857driver. 2858 2859@option{path} specifies the path to the host's TPM device, i.e., on 2860a Linux host this would be @code{/dev/tpm0}. 2861@option{path} is optional and by default @code{/dev/tpm0} is used. 2862 2863@option{cancel-path} specifies the path to the host TPM device's sysfs 2864entry allowing for cancellation of an ongoing TPM command. 2865@option{cancel-path} is optional and by default QEMU will search for the 2866sysfs entry to use. 2867 2868Some notes about using the host's TPM with the passthrough driver: 2869 2870The TPM device accessed by the passthrough driver must not be 2871used by any other application on the host. 2872 2873Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2874the VM's firmware (BIOS/UEFI) will not be able to initialize the 2875TPM again and may therefore not show a TPM-specific menu that would 2876otherwise allow the user to configure the TPM, e.g., allow the user to 2877enable/disable or activate/deactivate the TPM. 2878Further, if TPM ownership is released from within a VM then the host's TPM 2879will get disabled and deactivated. To enable and activate the 2880TPM again afterwards, the host has to be rebooted and the user is 2881required to enter the firmware's menu to enable and activate the TPM. 2882If the TPM is left disabled and/or deactivated most TPM commands will fail. 2883 2884To create a passthrough TPM use the following two options: 2885@example 2886-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2887@end example 2888Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2889@code{tpmdev=tpm0} in the device option. 2890 2891@item -tpmdev emulator,id=@var{id},chardev=@var{dev} 2892 2893(Linux-host only) Enable access to a TPM emulator using Unix domain socket based 2894chardev backend. 2895 2896@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server. 2897 2898To create a TPM emulator backend device with chardev socket backend: 2899@example 2900 2901-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0 2902 2903@end example 2904 2905ETEXI 2906 2907STEXI 2908@end table 2909ETEXI 2910DEFHEADING() 2911 2912#endif 2913 2914DEFHEADING(Linux/Multiboot boot specific:) 2915STEXI 2916 2917When using these options, you can use a given Linux or Multiboot 2918kernel without installing it in the disk image. It can be useful 2919for easier testing of various kernels. 2920 2921@table @option 2922ETEXI 2923 2924DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2925 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2926STEXI 2927@item -kernel @var{bzImage} 2928@findex -kernel 2929Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2930or in multiboot format. 2931ETEXI 2932 2933DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2934 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2935STEXI 2936@item -append @var{cmdline} 2937@findex -append 2938Use @var{cmdline} as kernel command line 2939ETEXI 2940 2941DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2942 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2943STEXI 2944@item -initrd @var{file} 2945@findex -initrd 2946Use @var{file} as initial ram disk. 2947 2948@item -initrd "@var{file1} arg=foo,@var{file2}" 2949 2950This syntax is only available with multiboot. 2951 2952Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2953first module. 2954ETEXI 2955 2956DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2957 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2958STEXI 2959@item -dtb @var{file} 2960@findex -dtb 2961Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2962on boot. 2963ETEXI 2964 2965STEXI 2966@end table 2967ETEXI 2968DEFHEADING() 2969 2970DEFHEADING(Debug/Expert options:) 2971STEXI 2972@table @option 2973ETEXI 2974 2975DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 2976 "-fw_cfg [name=]<name>,file=<file>\n" 2977 " add named fw_cfg entry with contents from file\n" 2978 "-fw_cfg [name=]<name>,string=<str>\n" 2979 " add named fw_cfg entry with contents from string\n", 2980 QEMU_ARCH_ALL) 2981STEXI 2982 2983@item -fw_cfg [name=]@var{name},file=@var{file} 2984@findex -fw_cfg 2985Add named fw_cfg entry with contents from file @var{file}. 2986 2987@item -fw_cfg [name=]@var{name},string=@var{str} 2988Add named fw_cfg entry with contents from string @var{str}. 2989 2990The terminating NUL character of the contents of @var{str} will not be 2991included as part of the fw_cfg item data. To insert contents with 2992embedded NUL characters, you have to use the @var{file} parameter. 2993 2994The fw_cfg entries are passed by QEMU through to the guest. 2995 2996Example: 2997@example 2998 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 2999@end example 3000creates an fw_cfg entry named opt/com.mycompany/blob with contents 3001from ./my_blob.bin. 3002 3003ETEXI 3004 3005DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 3006 "-serial dev redirect the serial port to char device 'dev'\n", 3007 QEMU_ARCH_ALL) 3008STEXI 3009@item -serial @var{dev} 3010@findex -serial 3011Redirect the virtual serial port to host character device 3012@var{dev}. The default device is @code{vc} in graphical mode and 3013@code{stdio} in non graphical mode. 3014 3015This option can be used several times to simulate up to 4 serial 3016ports. 3017 3018Use @code{-serial none} to disable all serial ports. 3019 3020Available character devices are: 3021@table @option 3022@item vc[:@var{W}x@var{H}] 3023Virtual console. Optionally, a width and height can be given in pixel with 3024@example 3025vc:800x600 3026@end example 3027It is also possible to specify width or height in characters: 3028@example 3029vc:80Cx24C 3030@end example 3031@item pty 3032[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3033@item none 3034No device is allocated. 3035@item null 3036void device 3037@item chardev:@var{id} 3038Use a named character device defined with the @code{-chardev} option. 3039@item /dev/XXX 3040[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3041parameters are set according to the emulated ones. 3042@item /dev/parport@var{N} 3043[Linux only, parallel port only] Use host parallel port 3044@var{N}. Currently SPP and EPP parallel port features can be used. 3045@item file:@var{filename} 3046Write output to @var{filename}. No character can be read. 3047@item stdio 3048[Unix only] standard input/output 3049@item pipe:@var{filename} 3050name pipe @var{filename} 3051@item COM@var{n} 3052[Windows only] Use host serial port @var{n} 3053@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3054This implements UDP Net Console. 3055When @var{remote_host} or @var{src_ip} are not specified 3056they default to @code{0.0.0.0}. 3057When not using a specified @var{src_port} a random port is automatically chosen. 3058 3059If you just want a simple readonly console you can use @code{netcat} or 3060@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3061@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3062will appear in the netconsole session. 3063 3064If you plan to send characters back via netconsole or you want to stop 3065and start QEMU a lot of times, you should have QEMU use the same 3066source port each time by using something like @code{-serial 3067udp::4555@@:4556} to QEMU. Another approach is to use a patched 3068version of netcat which can listen to a TCP port and send and receive 3069characters via udp. If you have a patched version of netcat which 3070activates telnet remote echo and single char transfer, then you can 3071use the following options to set up a netcat redirector to allow 3072telnet on port 5555 to access the QEMU port. 3073@table @code 3074@item QEMU Options: 3075-serial udp::4555@@:4556 3076@item netcat options: 3077-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3078@item telnet options: 3079localhost 5555 3080@end table 3081 3082@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3083The TCP Net Console has two modes of operation. It can send the serial 3084I/O to a location or wait for a connection from a location. By default 3085the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3086the @var{server} option QEMU will wait for a client socket application 3087to connect to the port before continuing, unless the @code{nowait} 3088option was specified. The @code{nodelay} option disables the Nagle buffering 3089algorithm. The @code{reconnect} option only applies if @var{noserver} is 3090set, if the connection goes down it will attempt to reconnect at the 3091given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3092one TCP connection at a time is accepted. You can use @code{telnet} to 3093connect to the corresponding character device. 3094@table @code 3095@item Example to send tcp console to 192.168.0.2 port 4444 3096-serial tcp:192.168.0.2:4444 3097@item Example to listen and wait on port 4444 for connection 3098-serial tcp::4444,server 3099@item Example to not wait and listen on ip 192.168.0.100 port 4444 3100-serial tcp:192.168.0.100:4444,server,nowait 3101@end table 3102 3103@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3104The telnet protocol is used instead of raw tcp sockets. The options 3105work the same as if you had specified @code{-serial tcp}. The 3106difference is that the port acts like a telnet server or client using 3107telnet option negotiation. This will also allow you to send the 3108MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3109sequence. Typically in unix telnet you do it with Control-] and then 3110type "send break" followed by pressing the enter key. 3111 3112@item websocket:@var{host}:@var{port},server[,nowait][,nodelay] 3113The WebSocket protocol is used instead of raw tcp socket. The port acts as 3114a WebSocket server. Client mode is not supported. 3115 3116@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3117A unix domain socket is used instead of a tcp socket. The option works the 3118same as if you had specified @code{-serial tcp} except the unix domain socket 3119@var{path} is used for connections. 3120 3121@item mon:@var{dev_string} 3122This is a special option to allow the monitor to be multiplexed onto 3123another serial port. The monitor is accessed with key sequence of 3124@key{Control-a} and then pressing @key{c}. 3125@var{dev_string} should be any one of the serial devices specified 3126above. An example to multiplex the monitor onto a telnet server 3127listening on port 4444 would be: 3128@table @code 3129@item -serial mon:telnet::4444,server,nowait 3130@end table 3131When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3132QEMU any more but will be passed to the guest instead. 3133 3134@item braille 3135Braille device. This will use BrlAPI to display the braille output on a real 3136or fake device. 3137 3138@item msmouse 3139Three button serial mouse. Configure the guest to use Microsoft protocol. 3140@end table 3141ETEXI 3142 3143DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3144 "-parallel dev redirect the parallel port to char device 'dev'\n", 3145 QEMU_ARCH_ALL) 3146STEXI 3147@item -parallel @var{dev} 3148@findex -parallel 3149Redirect the virtual parallel port to host device @var{dev} (same 3150devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3151be used to use hardware devices connected on the corresponding host 3152parallel port. 3153 3154This option can be used several times to simulate up to 3 parallel 3155ports. 3156 3157Use @code{-parallel none} to disable all parallel ports. 3158ETEXI 3159 3160DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3161 "-monitor dev redirect the monitor to char device 'dev'\n", 3162 QEMU_ARCH_ALL) 3163STEXI 3164@item -monitor @var{dev} 3165@findex -monitor 3166Redirect the monitor to host device @var{dev} (same devices as the 3167serial port). 3168The default device is @code{vc} in graphical mode and @code{stdio} in 3169non graphical mode. 3170Use @code{-monitor none} to disable the default monitor. 3171ETEXI 3172DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3173 "-qmp dev like -monitor but opens in 'control' mode\n", 3174 QEMU_ARCH_ALL) 3175STEXI 3176@item -qmp @var{dev} 3177@findex -qmp 3178Like -monitor but opens in 'control' mode. 3179ETEXI 3180DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3181 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3182 QEMU_ARCH_ALL) 3183STEXI 3184@item -qmp-pretty @var{dev} 3185@findex -qmp-pretty 3186Like -qmp but uses pretty JSON formatting. 3187ETEXI 3188 3189DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3190 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL) 3191STEXI 3192@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]] 3193@findex -mon 3194Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing 3195easing human reading and debugging. 3196ETEXI 3197 3198DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3199 "-debugcon dev redirect the debug console to char device 'dev'\n", 3200 QEMU_ARCH_ALL) 3201STEXI 3202@item -debugcon @var{dev} 3203@findex -debugcon 3204Redirect the debug console to host device @var{dev} (same devices as the 3205serial port). The debug console is an I/O port which is typically port 32060xe9; writing to that I/O port sends output to this device. 3207The default device is @code{vc} in graphical mode and @code{stdio} in 3208non graphical mode. 3209ETEXI 3210 3211DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3212 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3213STEXI 3214@item -pidfile @var{file} 3215@findex -pidfile 3216Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3217from a script. 3218ETEXI 3219 3220DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3221 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3222STEXI 3223@item -singlestep 3224@findex -singlestep 3225Run the emulation in single step mode. 3226ETEXI 3227 3228DEF("preconfig", 0, QEMU_OPTION_preconfig, \ 3229 "--preconfig pause QEMU before machine is initialized (experimental)\n", 3230 QEMU_ARCH_ALL) 3231STEXI 3232@item --preconfig 3233@findex --preconfig 3234Pause QEMU for interactive configuration before the machine is created, 3235which allows querying and configuring properties that will affect 3236machine initialization. Use QMP command 'x-exit-preconfig' to exit 3237the preconfig state and move to the next state (i.e. run guest if -S 3238isn't used or pause the second time if -S is used). This option is 3239experimental. 3240ETEXI 3241 3242DEF("S", 0, QEMU_OPTION_S, \ 3243 "-S freeze CPU at startup (use 'c' to start execution)\n", 3244 QEMU_ARCH_ALL) 3245STEXI 3246@item -S 3247@findex -S 3248Do not start CPU at startup (you must type 'c' in the monitor). 3249ETEXI 3250 3251DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3252 "-realtime [mlock=on|off]\n" 3253 " run qemu with realtime features\n" 3254 " mlock=on|off controls mlock support (default: on)\n", 3255 QEMU_ARCH_ALL) 3256STEXI 3257@item -realtime mlock=on|off 3258@findex -realtime 3259Run qemu with realtime features. 3260mlocking qemu and guest memory can be enabled via @option{mlock=on} 3261(enabled by default). 3262ETEXI 3263 3264DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, 3265 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" 3266 " run qemu with overcommit hints\n" 3267 " mem-lock=on|off controls memory lock support (default: off)\n" 3268 " cpu-pm=on|off controls cpu power management (default: off)\n", 3269 QEMU_ARCH_ALL) 3270STEXI 3271@item -overcommit mem-lock=on|off 3272@item -overcommit cpu-pm=on|off 3273@findex -overcommit 3274Run qemu with hints about host resource overcommit. The default is 3275to assume that host overcommits all resources. 3276 3277Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled 3278by default). This works when host memory is not overcommitted and reduces the 3279worst-case latency for guest. This is equivalent to @option{realtime}. 3280 3281Guest ability to manage power state of host cpus (increasing latency for other 3282processes on the same host cpu, but decreasing latency for guest) can be 3283enabled via @option{cpu-pm=on} (disabled by default). This works best when 3284host CPU is not overcommitted. When used, host estimates of CPU cycle and power 3285utilization will be incorrect, not taking into account guest idle time. 3286ETEXI 3287 3288DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3289 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3290STEXI 3291@item -gdb @var{dev} 3292@findex -gdb 3293Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3294connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3295stdio are reasonable use case. The latter is allowing to start QEMU from 3296within gdb and establish the connection via a pipe: 3297@example 3298(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3299@end example 3300ETEXI 3301 3302DEF("s", 0, QEMU_OPTION_s, \ 3303 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3304 QEMU_ARCH_ALL) 3305STEXI 3306@item -s 3307@findex -s 3308Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3309(@pxref{gdb_usage}). 3310ETEXI 3311 3312DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3313 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3314 QEMU_ARCH_ALL) 3315STEXI 3316@item -d @var{item1}[,...] 3317@findex -d 3318Enable logging of specified items. Use '-d help' for a list of log items. 3319ETEXI 3320 3321DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3322 "-D logfile output log to logfile (default stderr)\n", 3323 QEMU_ARCH_ALL) 3324STEXI 3325@item -D @var{logfile} 3326@findex -D 3327Output log in @var{logfile} instead of to stderr 3328ETEXI 3329 3330DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3331 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3332 QEMU_ARCH_ALL) 3333STEXI 3334@item -dfilter @var{range1}[,...] 3335@findex -dfilter 3336Filter debug output to that relevant to a range of target addresses. The filter 3337spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3338@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3339addresses and sizes required. For example: 3340@example 3341 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3342@end example 3343Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3344the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3345block starting at 0xffffffc00005f000. 3346ETEXI 3347 3348DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3349 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3350 QEMU_ARCH_ALL) 3351STEXI 3352@item -L @var{path} 3353@findex -L 3354Set the directory for the BIOS, VGA BIOS and keymaps. 3355 3356To list all the data directories, use @code{-L help}. 3357ETEXI 3358 3359DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3360 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3361STEXI 3362@item -bios @var{file} 3363@findex -bios 3364Set the filename for the BIOS. 3365ETEXI 3366 3367DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3368 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3369STEXI 3370@item -enable-kvm 3371@findex -enable-kvm 3372Enable KVM full virtualization support. This option is only available 3373if KVM support is enabled when compiling. 3374ETEXI 3375 3376DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \ 3377 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386) 3378STEXI 3379@item -enable-hax 3380@findex -enable-hax 3381Enable HAX (Hardware-based Acceleration eXecution) support. This option 3382is only available if HAX support is enabled when compiling. HAX is only 3383applicable to MAC and Windows platform, and thus does not conflict with 3384KVM. This option is deprecated, use @option{-accel hax} instead. 3385ETEXI 3386 3387DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3388 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3389DEF("xen-create", 0, QEMU_OPTION_xen_create, 3390 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3391 " warning: should not be used when xend is in use\n", 3392 QEMU_ARCH_ALL) 3393DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3394 "-xen-attach attach to existing xen domain\n" 3395 " xend will use this when starting QEMU\n", 3396 QEMU_ARCH_ALL) 3397DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict, 3398 "-xen-domid-restrict restrict set of available xen operations\n" 3399 " to specified domain id. (Does not affect\n" 3400 " xenpv machine type).\n", 3401 QEMU_ARCH_ALL) 3402STEXI 3403@item -xen-domid @var{id} 3404@findex -xen-domid 3405Specify xen guest domain @var{id} (XEN only). 3406@item -xen-create 3407@findex -xen-create 3408Create domain using xen hypercalls, bypassing xend. 3409Warning: should not be used when xend is in use (XEN only). 3410@item -xen-attach 3411@findex -xen-attach 3412Attach to existing xen domain. 3413xend will use this when starting QEMU (XEN only). 3414@findex -xen-domid-restrict 3415Restrict set of available xen operations to specified domain id (XEN only). 3416ETEXI 3417 3418DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3419 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3420STEXI 3421@item -no-reboot 3422@findex -no-reboot 3423Exit instead of rebooting. 3424ETEXI 3425 3426DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3427 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3428STEXI 3429@item -no-shutdown 3430@findex -no-shutdown 3431Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3432This allows for instance switching to monitor to commit changes to the 3433disk image. 3434ETEXI 3435 3436DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3437 "-loadvm [tag|id]\n" \ 3438 " start right away with a saved state (loadvm in monitor)\n", 3439 QEMU_ARCH_ALL) 3440STEXI 3441@item -loadvm @var{file} 3442@findex -loadvm 3443Start right away with a saved state (@code{loadvm} in monitor) 3444ETEXI 3445 3446#ifndef _WIN32 3447DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3448 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3449#endif 3450STEXI 3451@item -daemonize 3452@findex -daemonize 3453Daemonize the QEMU process after initialization. QEMU will not detach from 3454standard IO until it is ready to receive connections on any of its devices. 3455This option is a useful way for external programs to launch QEMU without having 3456to cope with initialization race conditions. 3457ETEXI 3458 3459DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3460 "-option-rom rom load a file, rom, into the option ROM space\n", 3461 QEMU_ARCH_ALL) 3462STEXI 3463@item -option-rom @var{file} 3464@findex -option-rom 3465Load the contents of @var{file} as an option ROM. 3466This option is useful to load things like EtherBoot. 3467ETEXI 3468 3469HXCOMM Silently ignored for compatibility 3470DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3471 3472DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3473 "-rtc [base=utc|localtime|<datetime>][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3474 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3475 QEMU_ARCH_ALL) 3476 3477STEXI 3478 3479@item -rtc [base=utc|localtime|@var{datetime}][,clock=host|rt|vm][,driftfix=none|slew] 3480@findex -rtc 3481Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3482UTC or local time, respectively. @code{localtime} is required for correct date in 3483MS-DOS or Windows. To start at a specific point in time, provide @var{datetime} in the 3484format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3485 3486By default the RTC is driven by the host system time. This allows using of the 3487RTC as accurate reference clock inside the guest, specifically if the host 3488time is smoothly following an accurate external reference clock, e.g. via NTP. 3489If you want to isolate the guest time from the host, you can set @option{clock} 3490to @code{rt} instead, which provides a host monotonic clock if host support it. 3491To even prevent the RTC from progressing during suspension, you can set @option{clock} 3492to @code{vm} (virtual clock). @samp{clock=vm} is recommended especially in 3493icount mode in order to preserve determinism; however, note that in icount mode 3494the speed of the virtual clock is variable and can in general differ from the 3495host clock. 3496 3497Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3498specifically with Windows' ACPI HAL. This option will try to figure out how 3499many timer interrupts were not processed by the Windows guest and will 3500re-inject them. 3501ETEXI 3502 3503DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3504 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3505 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3506 " instruction, enable aligning the host and virtual clocks\n" \ 3507 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3508STEXI 3509@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3510@findex -icount 3511Enable virtual instruction counter. The virtual cpu will execute one 3512instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3513then the virtual cpu speed will be automatically adjusted to keep virtual 3514time within a few seconds of real time. 3515 3516When the virtual cpu is sleeping, the virtual time will advance at default 3517speed unless @option{sleep=on|off} is specified. 3518With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3519instantly whenever the virtual cpu goes to sleep mode and will not advance 3520if no timer is enabled. This behavior give deterministic execution times from 3521the guest point of view. 3522 3523Note that while this option can give deterministic behavior, it does not 3524provide cycle accurate emulation. Modern CPUs contain superscalar out of 3525order cores with complex cache hierarchies. The number of instructions 3526executed often has little or no correlation with actual performance. 3527 3528@option{align=on} will activate the delay algorithm which will try 3529to synchronise the host clock and the virtual clock. The goal is to 3530have a guest running at the real frequency imposed by the shift option. 3531Whenever the guest clock is behind the host clock and if 3532@option{align=on} is specified then we print a message to the user 3533to inform about the delay. 3534Currently this option does not work when @option{shift} is @code{auto}. 3535Note: The sync algorithm will work for those shift values for which 3536the guest clock runs ahead of the host clock. Typically this happens 3537when the shift value is high (how high depends on the host machine). 3538 3539When @option{rr} option is specified deterministic record/replay is enabled. 3540Replay log is written into @var{filename} file in record mode and 3541read from this file in replay mode. 3542 3543Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3544at the start of execution recording. In replay mode this option is used 3545to load the initial VM state. 3546ETEXI 3547 3548DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3549 "-watchdog model\n" \ 3550 " enable virtual hardware watchdog [default=none]\n", 3551 QEMU_ARCH_ALL) 3552STEXI 3553@item -watchdog @var{model} 3554@findex -watchdog 3555Create a virtual hardware watchdog device. Once enabled (by a guest 3556action), the watchdog must be periodically polled by an agent inside 3557the guest or else the guest will be restarted. Choose a model for 3558which your guest has drivers. 3559 3560The @var{model} is the model of hardware watchdog to emulate. Use 3561@code{-watchdog help} to list available hardware models. Only one 3562watchdog can be enabled for a guest. 3563 3564The following models may be available: 3565@table @option 3566@item ib700 3567iBASE 700 is a very simple ISA watchdog with a single timer. 3568@item i6300esb 3569Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3570dual-timer watchdog. 3571@item diag288 3572A virtual watchdog for s390x backed by the diagnose 288 hypercall 3573(currently KVM only). 3574@end table 3575ETEXI 3576 3577DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3578 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \ 3579 " action when watchdog fires [default=reset]\n", 3580 QEMU_ARCH_ALL) 3581STEXI 3582@item -watchdog-action @var{action} 3583@findex -watchdog-action 3584 3585The @var{action} controls what QEMU will do when the watchdog timer 3586expires. 3587The default is 3588@code{reset} (forcefully reset the guest). 3589Other possible actions are: 3590@code{shutdown} (attempt to gracefully shutdown the guest), 3591@code{poweroff} (forcefully poweroff the guest), 3592@code{inject-nmi} (inject a NMI into the guest), 3593@code{pause} (pause the guest), 3594@code{debug} (print a debug message and continue), or 3595@code{none} (do nothing). 3596 3597Note that the @code{shutdown} action requires that the guest responds 3598to ACPI signals, which it may not be able to do in the sort of 3599situations where the watchdog would have expired, and thus 3600@code{-watchdog-action shutdown} is not recommended for production use. 3601 3602Examples: 3603 3604@table @code 3605@item -watchdog i6300esb -watchdog-action pause 3606@itemx -watchdog ib700 3607@end table 3608ETEXI 3609 3610DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3611 "-echr chr set terminal escape character instead of ctrl-a\n", 3612 QEMU_ARCH_ALL) 3613STEXI 3614 3615@item -echr @var{numeric_ascii_value} 3616@findex -echr 3617Change the escape character used for switching to the monitor when using 3618monitor and serial sharing. The default is @code{0x01} when using the 3619@code{-nographic} option. @code{0x01} is equal to pressing 3620@code{Control-a}. You can select a different character from the ascii 3621control keys where 1 through 26 map to Control-a through Control-z. For 3622instance you could use the either of the following to change the escape 3623character to Control-t. 3624@table @code 3625@item -echr 0x14 3626@itemx -echr 20 3627@end table 3628ETEXI 3629 3630DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3631 "-virtioconsole c\n" \ 3632 " set virtio console\n", QEMU_ARCH_ALL) 3633STEXI 3634@item -virtioconsole @var{c} 3635@findex -virtioconsole 3636Set virtio console. 3637This option is deprecated, please use @option{-device virtconsole} instead. 3638ETEXI 3639 3640DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3641 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3642STEXI 3643@item -show-cursor 3644@findex -show-cursor 3645Show cursor. 3646ETEXI 3647 3648DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3649 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3650STEXI 3651@item -tb-size @var{n} 3652@findex -tb-size 3653Set TB size. 3654ETEXI 3655 3656DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3657 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3658 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3659 "-incoming unix:socketpath\n" \ 3660 " prepare for incoming migration, listen on\n" \ 3661 " specified protocol and socket address\n" \ 3662 "-incoming fd:fd\n" \ 3663 "-incoming exec:cmdline\n" \ 3664 " accept incoming migration on given file descriptor\n" \ 3665 " or from given external command\n" \ 3666 "-incoming defer\n" \ 3667 " wait for the URI to be specified via migrate_incoming\n", 3668 QEMU_ARCH_ALL) 3669STEXI 3670@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3671@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3672@findex -incoming 3673Prepare for incoming migration, listen on a given tcp port. 3674 3675@item -incoming unix:@var{socketpath} 3676Prepare for incoming migration, listen on a given unix socket. 3677 3678@item -incoming fd:@var{fd} 3679Accept incoming migration from a given filedescriptor. 3680 3681@item -incoming exec:@var{cmdline} 3682Accept incoming migration as an output from specified external command. 3683 3684@item -incoming defer 3685Wait for the URI to be specified via migrate_incoming. The monitor can 3686be used to change settings (such as migration parameters) prior to issuing 3687the migrate_incoming to allow the migration to begin. 3688ETEXI 3689 3690DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3691 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3692STEXI 3693@item -only-migratable 3694@findex -only-migratable 3695Only allow migratable devices. Devices will not be allowed to enter an 3696unmigratable state. 3697ETEXI 3698 3699DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3700 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3701STEXI 3702@item -nodefaults 3703@findex -nodefaults 3704Don't create default devices. Normally, QEMU sets the default devices like serial 3705port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3706CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3707default devices. 3708ETEXI 3709 3710#ifndef _WIN32 3711DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3712 "-chroot dir chroot to dir just before starting the VM\n", 3713 QEMU_ARCH_ALL) 3714#endif 3715STEXI 3716@item -chroot @var{dir} 3717@findex -chroot 3718Immediately before starting guest execution, chroot to the specified 3719directory. Especially useful in combination with -runas. 3720ETEXI 3721 3722#ifndef _WIN32 3723DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3724 "-runas user change to user id user just before starting the VM\n" \ 3725 " user can be numeric uid:gid instead\n", 3726 QEMU_ARCH_ALL) 3727#endif 3728STEXI 3729@item -runas @var{user} 3730@findex -runas 3731Immediately before starting guest execution, drop root privileges, switching 3732to the specified user. 3733ETEXI 3734 3735DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3736 "-prom-env variable=value\n" 3737 " set OpenBIOS nvram variables\n", 3738 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3739STEXI 3740@item -prom-env @var{variable}=@var{value} 3741@findex -prom-env 3742Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3743ETEXI 3744DEF("semihosting", 0, QEMU_OPTION_semihosting, 3745 "-semihosting semihosting mode\n", 3746 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3747 QEMU_ARCH_MIPS) 3748STEXI 3749@item -semihosting 3750@findex -semihosting 3751Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3752ETEXI 3753DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3754 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3755 " semihosting configuration\n", 3756QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3757QEMU_ARCH_MIPS) 3758STEXI 3759@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3760@findex -semihosting-config 3761Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3762@table @option 3763@item target=@code{native|gdb|auto} 3764Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3765or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3766during debug sessions and @code{native} otherwise. 3767@item arg=@var{str1},arg=@var{str2},... 3768Allows the user to pass input arguments, and can be used multiple times to build 3769up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3770command line is still supported for backward compatibility. If both the 3771@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3772specified, the former is passed to semihosting as it always takes precedence. 3773@end table 3774ETEXI 3775DEF("old-param", 0, QEMU_OPTION_old_param, 3776 "-old-param old param mode\n", QEMU_ARCH_ARM) 3777STEXI 3778@item -old-param 3779@findex -old-param (ARM) 3780Old param mode (ARM only). 3781ETEXI 3782 3783DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3784 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \ 3785 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \ 3786 " Enable seccomp mode 2 system call filter (default 'off').\n" \ 3787 " use 'obsolete' to allow obsolete system calls that are provided\n" \ 3788 " by the kernel, but typically no longer used by modern\n" \ 3789 " C library implementations.\n" \ 3790 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \ 3791 " its privileges by blacklisting all set*uid|gid system calls.\n" \ 3792 " The value 'children' will deny set*uid|gid system calls for\n" \ 3793 " main QEMU process but will allow forks and execves to run unprivileged\n" \ 3794 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \ 3795 " blacklisting *fork and execve\n" \ 3796 " use 'resourcecontrol' to disable process affinity and schedular priority\n", 3797 QEMU_ARCH_ALL) 3798STEXI 3799@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}] 3800@findex -sandbox 3801Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3802disable it. The default is 'off'. 3803@table @option 3804@item obsolete=@var{string} 3805Enable Obsolete system calls 3806@item elevateprivileges=@var{string} 3807Disable set*uid|gid system calls 3808@item spawn=@var{string} 3809Disable *fork and execve 3810@item resourcecontrol=@var{string} 3811Disable process affinity and schedular priority 3812@end table 3813ETEXI 3814 3815DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3816 "-readconfig <file>\n", QEMU_ARCH_ALL) 3817STEXI 3818@item -readconfig @var{file} 3819@findex -readconfig 3820Read device configuration from @var{file}. This approach is useful when you want to spawn 3821QEMU process with many command line options but you don't want to exceed the command line 3822character limit. 3823ETEXI 3824DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3825 "-writeconfig <file>\n" 3826 " read/write config file\n", QEMU_ARCH_ALL) 3827STEXI 3828@item -writeconfig @var{file} 3829@findex -writeconfig 3830Write device configuration to @var{file}. The @var{file} can be either filename to save 3831command line and device configuration into file or dash @code{-}) character to print the 3832output to stdout. This can be later used as input file for @code{-readconfig} option. 3833ETEXI 3834 3835DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3836 "-no-user-config\n" 3837 " do not load default user-provided config files at startup\n", 3838 QEMU_ARCH_ALL) 3839STEXI 3840@item -no-user-config 3841@findex -no-user-config 3842The @code{-no-user-config} option makes QEMU not load any of the user-provided 3843config files on @var{sysconfdir}. 3844ETEXI 3845 3846DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3847 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3848 " specify tracing options\n", 3849 QEMU_ARCH_ALL) 3850STEXI 3851HXCOMM This line is not accurate, as some sub-options are backend-specific but 3852HXCOMM HX does not support conditional compilation of text. 3853@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 3854@findex -trace 3855@include qemu-option-trace.texi 3856ETEXI 3857 3858HXCOMM Internal use 3859DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3860DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3861 3862#ifdef __linux__ 3863DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3864 "-enable-fips enable FIPS 140-2 compliance\n", 3865 QEMU_ARCH_ALL) 3866#endif 3867STEXI 3868@item -enable-fips 3869@findex -enable-fips 3870Enable FIPS 140-2 compliance mode. 3871ETEXI 3872 3873HXCOMM Deprecated by -machine accel=tcg property 3874DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3875 3876DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3877 "-msg timestamp[=on|off]\n" 3878 " change the format of messages\n" 3879 " on|off controls leading timestamps (default:on)\n", 3880 QEMU_ARCH_ALL) 3881STEXI 3882@item -msg timestamp[=on|off] 3883@findex -msg 3884prepend a timestamp to each log message.(default:on) 3885ETEXI 3886 3887DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3888 "-dump-vmstate <file>\n" 3889 " Output vmstate information in JSON format to file.\n" 3890 " Use the scripts/vmstate-static-checker.py file to\n" 3891 " check for possible regressions in migration code\n" 3892 " by comparing two such vmstate dumps.\n", 3893 QEMU_ARCH_ALL) 3894STEXI 3895@item -dump-vmstate @var{file} 3896@findex -dump-vmstate 3897Dump json-encoded vmstate information for current machine type to file 3898in @var{file} 3899ETEXI 3900 3901DEF("enable-sync-profile", 0, QEMU_OPTION_enable_sync_profile, 3902 "-enable-sync-profile\n" 3903 " enable synchronization profiling\n", 3904 QEMU_ARCH_ALL) 3905STEXI 3906@item -enable-sync-profile 3907@findex -enable-sync-profile 3908Enable synchronization profiling. 3909ETEXI 3910 3911STEXI 3912@end table 3913ETEXI 3914DEFHEADING() 3915 3916DEFHEADING(Generic object creation:) 3917STEXI 3918@table @option 3919ETEXI 3920 3921DEF("object", HAS_ARG, QEMU_OPTION_object, 3922 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3923 " create a new object of type TYPENAME setting properties\n" 3924 " in the order they are specified. Note that the 'id'\n" 3925 " property must be set. These objects are placed in the\n" 3926 " '/objects' path.\n", 3927 QEMU_ARCH_ALL) 3928STEXI 3929@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3930@findex -object 3931Create a new object of type @var{typename} setting properties 3932in the order they are specified. Note that the 'id' 3933property must be set. These objects are placed in the 3934'/objects' path. 3935 3936@table @option 3937 3938@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} 3939 3940Creates a memory file backend object, which can be used to back 3941the guest RAM with huge pages. 3942 3943The @option{id} parameter is a unique ID that will be used to reference this 3944memory region when configuring the @option{-numa} argument. 3945 3946The @option{size} option provides the size of the memory region, and accepts 3947common suffixes, eg @option{500M}. 3948 3949The @option{mem-path} provides the path to either a shared memory or huge page 3950filesystem mount. 3951 3952The @option{share} boolean option determines whether the memory 3953region is marked as private to QEMU, or shared. The latter allows 3954a co-operating external process to access the QEMU memory region. 3955 3956The @option{share} is also required for pvrdma devices due to 3957limitations in the RDMA API provided by Linux. 3958 3959Setting share=on might affect the ability to configure NUMA 3960bindings for the memory backend under some circumstances, see 3961Documentation/vm/numa_memory_policy.txt on the Linux kernel 3962source tree for additional details. 3963 3964Setting the @option{discard-data} boolean option to @var{on} 3965indicates that file contents can be destroyed when QEMU exits, 3966to avoid unnecessarily flushing data to the backing file. Note 3967that @option{discard-data} is only an optimization, and QEMU 3968might not discard file contents if it aborts unexpectedly or is 3969terminated using SIGKILL. 3970 3971The @option{merge} boolean option enables memory merge, also known as 3972MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for 3973memory deduplication. 3974 3975Setting the @option{dump} boolean option to @var{off} excludes the memory from 3976core dumps. This feature is also known as MADV_DONTDUMP. 3977 3978The @option{prealloc} boolean option enables memory preallocation. 3979 3980The @option{host-nodes} option binds the memory range to a list of NUMA host 3981nodes. 3982 3983The @option{policy} option sets the NUMA policy to one of the following values: 3984 3985@table @option 3986@item @var{default} 3987default host policy 3988 3989@item @var{preferred} 3990prefer the given host node list for allocation 3991 3992@item @var{bind} 3993restrict memory allocation to the given host node list 3994 3995@item @var{interleave} 3996interleave memory allocations across the given host node list 3997@end table 3998 3999The @option{align} option specifies the base address alignment when 4000QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg 4001@option{2M}. Some backend store specified by @option{mem-path} 4002requires an alignment different than the default one used by QEMU, eg 4003the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In 4004such cases, users can specify the required alignment via this option. 4005 4006The @option{pmem} option specifies whether the backing file specified 4007by @option{mem-path} is in host persistent memory that can be accessed 4008using the SNIA NVM programming model (e.g. Intel NVDIMM). 4009If @option{pmem} is set to 'on', QEMU will take necessary operations to 4010guarantee the persistence of its own writes to @option{mem-path} 4011(e.g. in vNVDIMM label emulation and live migration). 4012 4013@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} 4014 4015Creates a memory backend object, which can be used to back the guest RAM. 4016Memory backend objects offer more control than the @option{-m} option that is 4017traditionally used to define guest RAM. Please refer to 4018@option{memory-backend-file} for a description of the options. 4019 4020@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} 4021 4022Creates an anonymous memory file backend object, which allows QEMU to 4023share the memory with an external process (e.g. when using 4024vhost-user). The memory is allocated with memfd and optional 4025sealing. (Linux only) 4026 4027The @option{seal} option creates a sealed-file, that will block 4028further resizing the memory ('on' by default). 4029 4030The @option{hugetlb} option specify the file to be created resides in 4031the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with 4032the @option{hugetlb} option, the @option{hugetlbsize} option specify 4033the hugetlb page size on systems that support multiple hugetlb page 4034sizes (it must be a power of 2 value supported by the system). 4035 4036In some versions of Linux, the @option{hugetlb} option is incompatible 4037with the @option{seal} option (requires at least Linux 4.16). 4038 4039Please refer to @option{memory-backend-file} for a description of the 4040other options. 4041 4042@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4043 4044Creates a random number generator backend which obtains entropy from 4045a device on the host. The @option{id} parameter is a unique ID that 4046will be used to reference this entropy backend from the @option{virtio-rng} 4047device. The @option{filename} parameter specifies which file to obtain 4048entropy from and if omitted defaults to @option{/dev/random}. 4049 4050@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4051 4052Creates a random number generator backend which obtains entropy from 4053an external daemon running on the host. The @option{id} parameter is 4054a unique ID that will be used to reference this entropy backend from 4055the @option{virtio-rng} device. The @option{chardev} parameter is 4056the unique ID of a character device backend that provides the connection 4057to the RNG daemon. 4058 4059@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4060 4061Creates a TLS anonymous credentials object, which can be used to provide 4062TLS support on network backends. The @option{id} parameter is a unique 4063ID which network backends will use to access the credentials. The 4064@option{endpoint} is either @option{server} or @option{client} depending 4065on whether the QEMU network backend that uses the credentials will be 4066acting as a client or as a server. If @option{verify-peer} is enabled 4067(the default) then once the handshake is completed, the peer credentials 4068will be verified, though this is a no-op for anonymous credentials. 4069 4070The @var{dir} parameter tells QEMU where to find the credential 4071files. For server endpoints, this directory may contain a file 4072@var{dh-params.pem} providing diffie-hellman parameters to use 4073for the TLS server. If the file is missing, QEMU will generate 4074a set of DH parameters at startup. This is a computationally 4075expensive operation that consumes random pool entropy, so it is 4076recommended that a persistent set of parameters be generated 4077upfront and saved. 4078 4079@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] 4080 4081Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide 4082TLS support on network backends. The @option{id} parameter is a unique 4083ID which network backends will use to access the credentials. The 4084@option{endpoint} is either @option{server} or @option{client} depending 4085on whether the QEMU network backend that uses the credentials will be 4086acting as a client or as a server. For clients only, @option{username} 4087is the username which will be sent to the server. If omitted 4088it defaults to ``qemu''. 4089 4090The @var{dir} parameter tells QEMU where to find the keys file. 4091It is called ``@var{dir}/keys.psk'' and contains ``username:key'' 4092pairs. This file can most easily be created using the GnuTLS 4093@code{psktool} program. 4094 4095For server endpoints, @var{dir} may also contain a file 4096@var{dh-params.pem} providing diffie-hellman parameters to use 4097for the TLS server. If the file is missing, QEMU will generate 4098a set of DH parameters at startup. This is a computationally 4099expensive operation that consumes random pool entropy, so it is 4100recommended that a persistent set of parameters be generated 4101up front and saved. 4102 4103@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} 4104 4105Creates a TLS anonymous credentials object, which can be used to provide 4106TLS support on network backends. The @option{id} parameter is a unique 4107ID which network backends will use to access the credentials. The 4108@option{endpoint} is either @option{server} or @option{client} depending 4109on whether the QEMU network backend that uses the credentials will be 4110acting as a client or as a server. If @option{verify-peer} is enabled 4111(the default) then once the handshake is completed, the peer credentials 4112will be verified. With x509 certificates, this implies that the clients 4113must be provided with valid client certificates too. 4114 4115The @var{dir} parameter tells QEMU where to find the credential 4116files. For server endpoints, this directory may contain a file 4117@var{dh-params.pem} providing diffie-hellman parameters to use 4118for the TLS server. If the file is missing, QEMU will generate 4119a set of DH parameters at startup. This is a computationally 4120expensive operation that consumes random pool entropy, so it is 4121recommended that a persistent set of parameters be generated 4122upfront and saved. 4123 4124For x509 certificate credentials the directory will contain further files 4125providing the x509 certificates. The certificates must be stored 4126in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4127@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4128@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4129 4130For the @var{server-key.pem} and @var{client-key.pem} files which 4131contain sensitive private keys, it is possible to use an encrypted 4132version by providing the @var{passwordid} parameter. This provides 4133the ID of a previously created @code{secret} object containing the 4134password for decryption. 4135 4136The @var{priority} parameter allows to override the global default 4137priority used by gnutls. This can be useful if the system administrator 4138needs to use a weaker set of crypto priorities for QEMU without 4139potentially forcing the weakness onto all applications. Or conversely 4140if one wants wants a stronger default for QEMU than for all other 4141applications, they can do this through this parameter. Its format is 4142a gnutls priority string as described at 4143@url{https://gnutls.org/manual/html_node/Priority-Strings.html}. 4144 4145@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4146 4147Interval @var{t} can't be 0, this filter batches the packet delivery: all 4148packets arriving in a given interval on netdev @var{netdevid} are delayed 4149until the end of the interval. Interval is in microseconds. 4150@option{status} is optional that indicate whether the netfilter is 4151on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4152 4153queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4154 4155@option{all}: the filter is attached both to the receive and the transmit 4156 queue of the netdev (default). 4157 4158@option{rx}: the filter is attached to the receive queue of the netdev, 4159 where it will receive packets sent to the netdev. 4160 4161@option{tx}: the filter is attached to the transmit queue of the netdev, 4162 where it will receive packets sent by the netdev. 4163 4164@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4165 4166filter-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. 4167 4168@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4169 4170filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4171@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag, 4172filter-redirector will redirect packet with vnet_hdr_len. 4173Create a filter-redirector we need to differ outdev id from indev id, id can not 4174be the same. we can just use indev or outdev, but at least one of indev or outdev 4175need to be specified. 4176 4177@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support] 4178 4179Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4180secondary from primary to keep secondary tcp connection,and rewrite 4181tcp packet to primary from secondary make tcp packet can be handled by 4182client.if it has the vnet_hdr_support flag, we can parse packet with vnet header. 4183 4184usage: 4185colo secondary: 4186-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4187-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4188-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4189 4190@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4191 4192Dump the network traffic on netdev @var{dev} to the file specified by 4193@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4194The file format is libpcap, so it can be analyzed with tools such as tcpdump 4195or Wireshark. 4196 4197@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support] 4198 4199Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4200secondary packet. If the packets are same, we will output primary 4201packet to outdev@var{chardevid}, else we will notify colo-frame 4202do checkpoint and send primary packet to outdev@var{chardevid}. 4203if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len. 4204 4205we must use it with the help of filter-mirror and filter-redirector. 4206 4207@example 4208 4209primary: 4210-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4211-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4212-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4213-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4214-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4215-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4216-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4217-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4218-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4219-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4220-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4221-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4222 4223secondary: 4224-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4225-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4226-chardev socket,id=red0,host=3.3.3.3,port=9003 4227-chardev socket,id=red1,host=3.3.3.3,port=9004 4228-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4229-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4230 4231@end example 4232 4233If you want to know the detail of above command line, you can read 4234the colo-compare git log. 4235 4236@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4237 4238Creates a cryptodev backend which executes crypto opreation from 4239the QEMU cipher APIS. The @var{id} parameter is 4240a unique ID that will be used to reference this cryptodev backend from 4241the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4242which specify the queue number of cryptodev backend, the default of 4243@var{queues} is 1. 4244 4245@example 4246 4247 # qemu-system-x86_64 \ 4248 [...] \ 4249 -object cryptodev-backend-builtin,id=cryptodev0 \ 4250 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4251 [...] 4252@end example 4253 4254@item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}] 4255 4256Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}. 4257The @var{id} parameter is a unique ID that will be used to reference this 4258cryptodev backend from the @option{virtio-crypto} device. 4259The chardev should be a unix domain socket backed one. The vhost-user uses 4260a specifically defined protocol to pass vhost ioctl replacement messages 4261to an application on the other end of the socket. 4262The @var{queues} parameter is optional, which specify the queue number 4263of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1. 4264 4265@example 4266 4267 # qemu-system-x86_64 \ 4268 [...] \ 4269 -chardev socket,id=chardev0,path=/path/to/socket \ 4270 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \ 4271 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4272 [...] 4273@end example 4274 4275@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4276@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4277 4278Defines a secret to store a password, encryption key, or some other sensitive 4279data. The sensitive data can either be passed directly via the @var{data} 4280parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4281parameter is insecure unless the sensitive data is encrypted. 4282 4283The sensitive data can be provided in raw format (the default), or base64. 4284When encoded as JSON, the raw format only supports valid UTF-8 characters, 4285so base64 is recommended for sending binary data. QEMU will convert from 4286which ever format is provided to the format it needs internally. eg, an 4287RBD password can be provided in raw format, even though it will be base64 4288encoded when passed onto the RBD sever. 4289 4290For added protection, it is possible to encrypt the data associated with 4291a secret using the AES-256-CBC cipher. Use of encryption is indicated 4292by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4293parameter provides the ID of a previously defined secret that contains 4294the AES-256 decryption key. This key should be 32-bytes long and be 4295base64 encoded. The @var{iv} parameter provides the random initialization 4296vector used for encryption of this particular secret and should be a 4297base64 encrypted string of the 16-byte IV. 4298 4299The simplest (insecure) usage is to provide the secret inline 4300 4301@example 4302 4303 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4304 4305@end example 4306 4307The simplest secure usage is to provide the secret via a file 4308 4309 # printf "letmein" > mypasswd.txt 4310 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4311 4312For greater security, AES-256-CBC should be used. To illustrate usage, 4313consider the openssl command line tool which can encrypt the data. Note 4314that when encrypting, the plaintext must be padded to the cipher block 4315size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4316 4317First a master key needs to be created in base64 encoding: 4318 4319@example 4320 # openssl rand -base64 32 > key.b64 4321 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4322@end example 4323 4324Each secret to be encrypted needs to have a random initialization vector 4325generated. These do not need to be kept secret 4326 4327@example 4328 # openssl rand -base64 16 > iv.b64 4329 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4330@end example 4331 4332The secret to be defined can now be encrypted, in this case we're 4333telling openssl to base64 encode the result, but it could be left 4334as raw bytes if desired. 4335 4336@example 4337 # SECRET=$(printf "letmein" | 4338 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4339@end example 4340 4341When launching QEMU, create a master secret pointing to @code{key.b64} 4342and specify that to be used to decrypt the user password. Pass the 4343contents of @code{iv.b64} to the second secret 4344 4345@example 4346 # $QEMU \ 4347 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4348 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4349 data=$SECRET,iv=$(<iv.b64) 4350@end example 4351 4352@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}] 4353 4354Create a Secure Encrypted Virtualization (SEV) guest object, which can be used 4355to provide the guest memory encryption support on AMD processors. 4356 4357When memory encryption is enabled, one of the physical address bit (aka the 4358C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos} 4359is used to provide the C-bit position. The C-bit position is Host family dependent 4360hence user must provide this value. On EPYC, the value should be 47. 4361 4362When memory encryption is enabled, we loose certain bits in physical address space. 4363The @option{reduced-phys-bits} is used to provide the number of bits we loose in 4364physical address space. Similar to C-bit, the value is Host family dependent. 4365On EPYC, the value should be 5. 4366 4367The @option{sev-device} provides the device file to use for communicating with 4368the SEV firmware running inside AMD Secure Processor. The default device is 4369'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are 4370created by CCP driver. 4371 4372The @option{policy} provides the guest policy to be enforced by the SEV firmware 4373and restrict what configuration and operational commands can be performed on this 4374guest by the hypervisor. The policy should be provided by the guest owner and is 4375bound to the guest and cannot be changed throughout the lifetime of the guest. 4376The default is 0. 4377 4378If guest @option{policy} allows sharing the key with another SEV guest then 4379@option{handle} can be use to provide handle of the guest from which to share 4380the key. 4381 4382The @option{dh-cert-file} and @option{session-file} provides the guest owner's 4383Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters 4384are used for establishing a cryptographic session with the guest owner to 4385negotiate keys used for attestation. The file must be encoded in base64. 4386 4387e.g to launch a SEV guest 4388@example 4389 # $QEMU \ 4390 ...... 4391 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ 4392 -machine ...,memory-encryption=sev0 4393 ..... 4394 4395@end example 4396@end table 4397 4398ETEXI 4399 4400 4401HXCOMM This is the last statement. Insert new options before this line! 4402STEXI 4403@end table 4404ETEXI 4405
