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\n" 542 " When debug-threads is enabled, individual threads are given a separate name\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" 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 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" 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 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 spice-app[,gl=on|off]\n" 1215 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 1216 " [,window_close=on|off][,gl=on|core|es|off]\n" 1217 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 1218 "-display vnc=<display>[,<optargs>]\n" 1219 "-display curses\n" 1220 "-display none\n" 1221 "-display egl-headless[,rendernode=<file>]" 1222 " select display type\n" 1223 "The default display is equivalent to\n" 1224#if defined(CONFIG_GTK) 1225 "\t\"-display gtk\"\n" 1226#elif defined(CONFIG_SDL) 1227 "\t\"-display sdl\"\n" 1228#elif defined(CONFIG_COCOA) 1229 "\t\"-display cocoa\"\n" 1230#elif defined(CONFIG_VNC) 1231 "\t\"-vnc localhost:0,to=99,id=default\"\n" 1232#else 1233 "\t\"-display none\"\n" 1234#endif 1235 , QEMU_ARCH_ALL) 1236STEXI 1237@item -display @var{type} 1238@findex -display 1239Select type of display to use. This option is a replacement for the 1240old style -sdl/-curses/... options. Valid values for @var{type} are 1241@table @option 1242@item sdl 1243Display video output via SDL (usually in a separate graphics 1244window; see the SDL documentation for other possibilities). 1245@item curses 1246Display video output via curses. For graphics device models which 1247support a text mode, QEMU can display this output using a 1248curses/ncurses interface. Nothing is displayed when the graphics 1249device is in graphical mode or if the graphics device does not support 1250a text mode. Generally only the VGA device models support text mode. 1251@item none 1252Do not display video output. The guest will still see an emulated 1253graphics card, but its output will not be displayed to the QEMU 1254user. This option differs from the -nographic option in that it 1255only affects what is done with video output; -nographic also changes 1256the destination of the serial and parallel port data. 1257@item gtk 1258Display video output in a GTK window. This interface provides drop-down 1259menus and other UI elements to configure and control the VM during 1260runtime. 1261@item vnc 1262Start a VNC server on display <arg> 1263@item egl-headless 1264Offload all OpenGL operations to a local DRI device. For any graphical display, 1265this display needs to be paired with either VNC or SPICE displays. 1266@item spice-app 1267Start QEMU as a Spice server and launch the default Spice client 1268application. The Spice server will redirect the serial consoles and 1269QEMU monitors. (Since 4.0) 1270@end table 1271ETEXI 1272 1273DEF("nographic", 0, QEMU_OPTION_nographic, 1274 "-nographic disable graphical output and redirect serial I/Os to console\n", 1275 QEMU_ARCH_ALL) 1276STEXI 1277@item -nographic 1278@findex -nographic 1279Normally, if QEMU is compiled with graphical window support, it displays 1280output such as guest graphics, guest console, and the QEMU monitor in a 1281window. With this option, you can totally disable graphical output so 1282that QEMU is a simple command line application. The emulated serial port 1283is redirected on the console and muxed with the monitor (unless 1284redirected elsewhere explicitly). Therefore, you can still use QEMU to 1285debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1286switching between the console and monitor. 1287ETEXI 1288 1289DEF("curses", 0, QEMU_OPTION_curses, 1290 "-curses shorthand for -display curses\n", 1291 QEMU_ARCH_ALL) 1292STEXI 1293@item -curses 1294@findex -curses 1295Normally, if QEMU is compiled with graphical window support, it displays 1296output such as guest graphics, guest console, and the QEMU monitor in a 1297window. With this option, QEMU can display the VGA output when in text 1298mode using a curses/ncurses interface. Nothing is displayed in graphical 1299mode. 1300ETEXI 1301 1302DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1303 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1304 QEMU_ARCH_ALL) 1305STEXI 1306@item -alt-grab 1307@findex -alt-grab 1308Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1309affects the special keys (for fullscreen, monitor-mode switching, etc). 1310ETEXI 1311 1312DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1313 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1314 QEMU_ARCH_ALL) 1315STEXI 1316@item -ctrl-grab 1317@findex -ctrl-grab 1318Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1319affects the special keys (for fullscreen, monitor-mode switching, etc). 1320ETEXI 1321 1322DEF("no-quit", 0, QEMU_OPTION_no_quit, 1323 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1324STEXI 1325@item -no-quit 1326@findex -no-quit 1327Disable SDL window close capability. 1328ETEXI 1329 1330DEF("sdl", 0, QEMU_OPTION_sdl, 1331 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1332STEXI 1333@item -sdl 1334@findex -sdl 1335Enable SDL. 1336ETEXI 1337 1338DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1339 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1340 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1341 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1342 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1343 " [,tls-ciphers=<list>]\n" 1344 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1345 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1346 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1347 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1348 " [,jpeg-wan-compression=[auto|never|always]]\n" 1349 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1350 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1351 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1352 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1353 " [,gl=[on|off]][,rendernode=<file>]\n" 1354 " enable spice\n" 1355 " at least one of {port, tls-port} is mandatory\n", 1356 QEMU_ARCH_ALL) 1357STEXI 1358@item -spice @var{option}[,@var{option}[,...]] 1359@findex -spice 1360Enable the spice remote desktop protocol. Valid options are 1361 1362@table @option 1363 1364@item port=<nr> 1365Set the TCP port spice is listening on for plaintext channels. 1366 1367@item addr=<addr> 1368Set the IP address spice is listening on. Default is any address. 1369 1370@item ipv4 1371@itemx ipv6 1372@itemx unix 1373Force using the specified IP version. 1374 1375@item password=<secret> 1376Set the password you need to authenticate. 1377 1378@item sasl 1379Require that the client use SASL to authenticate with the spice. 1380The exact choice of authentication method used is controlled from the 1381system / user's SASL configuration file for the 'qemu' service. This 1382is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1383unprivileged user, an environment variable SASL_CONF_PATH can be used 1384to make it search alternate locations for the service config. 1385While some SASL auth methods can also provide data encryption (eg GSSAPI), 1386it is recommended that SASL always be combined with the 'tls' and 1387'x509' settings to enable use of SSL and server certificates. This 1388ensures a data encryption preventing compromise of authentication 1389credentials. 1390 1391@item disable-ticketing 1392Allow client connects without authentication. 1393 1394@item disable-copy-paste 1395Disable copy paste between the client and the guest. 1396 1397@item disable-agent-file-xfer 1398Disable spice-vdagent based file-xfer between the client and the guest. 1399 1400@item tls-port=<nr> 1401Set the TCP port spice is listening on for encrypted channels. 1402 1403@item x509-dir=<dir> 1404Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1405 1406@item x509-key-file=<file> 1407@itemx x509-key-password=<file> 1408@itemx x509-cert-file=<file> 1409@itemx x509-cacert-file=<file> 1410@itemx x509-dh-key-file=<file> 1411The x509 file names can also be configured individually. 1412 1413@item tls-ciphers=<list> 1414Specify which ciphers to use. 1415 1416@item tls-channel=[main|display|cursor|inputs|record|playback] 1417@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1418Force specific channel to be used with or without TLS encryption. The 1419options can be specified multiple times to configure multiple 1420channels. The special name "default" can be used to set the default 1421mode. For channels which are not explicitly forced into one mode the 1422spice client is allowed to pick tls/plaintext as he pleases. 1423 1424@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1425Configure image compression (lossless). 1426Default is auto_glz. 1427 1428@item jpeg-wan-compression=[auto|never|always] 1429@itemx zlib-glz-wan-compression=[auto|never|always] 1430Configure wan image compression (lossy for slow links). 1431Default is auto. 1432 1433@item streaming-video=[off|all|filter] 1434Configure video stream detection. Default is off. 1435 1436@item agent-mouse=[on|off] 1437Enable/disable passing mouse events via vdagent. Default is on. 1438 1439@item playback-compression=[on|off] 1440Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1441 1442@item seamless-migration=[on|off] 1443Enable/disable spice seamless migration. Default is off. 1444 1445@item gl=[on|off] 1446Enable/disable OpenGL context. Default is off. 1447 1448@item rendernode=<file> 1449DRM render node for OpenGL rendering. If not specified, it will pick 1450the first available. (Since 2.9) 1451 1452@end table 1453ETEXI 1454 1455DEF("portrait", 0, QEMU_OPTION_portrait, 1456 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1457 QEMU_ARCH_ALL) 1458STEXI 1459@item -portrait 1460@findex -portrait 1461Rotate graphical output 90 deg left (only PXA LCD). 1462ETEXI 1463 1464DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1465 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1466 QEMU_ARCH_ALL) 1467STEXI 1468@item -rotate @var{deg} 1469@findex -rotate 1470Rotate graphical output some deg left (only PXA LCD). 1471ETEXI 1472 1473DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1474 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1475 " select video card type\n", QEMU_ARCH_ALL) 1476STEXI 1477@item -vga @var{type} 1478@findex -vga 1479Select type of VGA card to emulate. Valid values for @var{type} are 1480@table @option 1481@item cirrus 1482Cirrus Logic GD5446 Video card. All Windows versions starting from 1483Windows 95 should recognize and use this graphic card. For optimal 1484performances, use 16 bit color depth in the guest and the host OS. 1485(This card was the default before QEMU 2.2) 1486@item std 1487Standard VGA card with Bochs VBE extensions. If your guest OS 1488supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1489to use high resolution modes (>= 1280x1024x16) then you should use 1490this option. (This card is the default since QEMU 2.2) 1491@item vmware 1492VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1493recent XFree86/XOrg server or Windows guest with a driver for this 1494card. 1495@item qxl 1496QXL paravirtual graphic card. It is VGA compatible (including VESA 14972.0 VBE support). Works best with qxl guest drivers installed though. 1498Recommended choice when using the spice protocol. 1499@item tcx 1500(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1501sun4m machines and offers both 8-bit and 24-bit colour depths at a 1502fixed resolution of 1024x768. 1503@item cg3 1504(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1505for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1506resolutions aimed at people wishing to run older Solaris versions. 1507@item virtio 1508Virtio VGA card. 1509@item none 1510Disable VGA card. 1511@end table 1512ETEXI 1513 1514DEF("full-screen", 0, QEMU_OPTION_full_screen, 1515 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1516STEXI 1517@item -full-screen 1518@findex -full-screen 1519Start in full screen. 1520ETEXI 1521 1522DEF("g", 1, QEMU_OPTION_g , 1523 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1524 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1525STEXI 1526@item -g @var{width}x@var{height}[x@var{depth}] 1527@findex -g 1528Set the initial graphical resolution and depth (PPC, SPARC only). 1529ETEXI 1530 1531DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1532 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1533STEXI 1534@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1535@findex -vnc 1536Normally, if QEMU is compiled with graphical window support, it displays 1537output such as guest graphics, guest console, and the QEMU monitor in a 1538window. With this option, you can have QEMU listen on VNC display 1539@var{display} and redirect the VGA display over the VNC session. It is 1540very useful to enable the usb tablet device when using this option 1541(option @option{-device usb-tablet}). When using the VNC display, you 1542must use the @option{-k} parameter to set the keyboard layout if you are 1543not using en-us. Valid syntax for the @var{display} is 1544 1545@table @option 1546 1547@item to=@var{L} 1548 1549With this option, QEMU will try next available VNC @var{display}s, until the 1550number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1551available, e.g. port 5900+@var{display} is already used by another 1552application. By default, to=0. 1553 1554@item @var{host}:@var{d} 1555 1556TCP connections will only be allowed from @var{host} on display @var{d}. 1557By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1558be omitted in which case the server will accept connections from any host. 1559 1560@item unix:@var{path} 1561 1562Connections will be allowed over UNIX domain sockets where @var{path} is the 1563location of a unix socket to listen for connections on. 1564 1565@item none 1566 1567VNC is initialized but not started. The monitor @code{change} command 1568can be used to later start the VNC server. 1569 1570@end table 1571 1572Following the @var{display} value there may be one or more @var{option} flags 1573separated by commas. Valid options are 1574 1575@table @option 1576 1577@item reverse 1578 1579Connect to a listening VNC client via a ``reverse'' connection. The 1580client is specified by the @var{display}. For reverse network 1581connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1582is a TCP port number, not a display number. 1583 1584@item websocket 1585 1586Opens an additional TCP listening port dedicated to VNC Websocket connections. 1587If a bare @var{websocket} option is given, the Websocket port is 15885700+@var{display}. An alternative port can be specified with the 1589syntax @code{websocket}=@var{port}. 1590 1591If @var{host} is specified connections will only be allowed from this host. 1592It is possible to control the websocket listen address independently, using 1593the syntax @code{websocket}=@var{host}:@var{port}. 1594 1595If no TLS credentials are provided, the websocket connection runs in 1596unencrypted mode. If TLS credentials are provided, the websocket connection 1597requires encrypted client connections. 1598 1599@item password 1600 1601Require that password based authentication is used for client connections. 1602 1603The password must be set separately using the @code{set_password} command in 1604the @ref{pcsys_monitor}. The syntax to change your password is: 1605@code{set_password <protocol> <password>} where <protocol> could be either 1606"vnc" or "spice". 1607 1608If you would like to change <protocol> password expiration, you should use 1609@code{expire_password <protocol> <expiration-time>} where expiration time could 1610be one of the following options: now, never, +seconds or UNIX time of 1611expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1612to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1613date and time). 1614 1615You can also use keywords "now" or "never" for the expiration time to 1616allow <protocol> password to expire immediately or never expire. 1617 1618@item tls-creds=@var{ID} 1619 1620Provides the ID of a set of TLS credentials to use to secure the 1621VNC server. They will apply to both the normal VNC server socket 1622and the websocket socket (if enabled). Setting TLS credentials 1623will cause the VNC server socket to enable the VeNCrypt auth 1624mechanism. The credentials should have been previously created 1625using the @option{-object tls-creds} argument. 1626 1627@item tls-authz=@var{ID} 1628 1629Provides the ID of the QAuthZ authorization object against which 1630the client's x509 distinguished name will validated. This object is 1631only resolved at time of use, so can be deleted and recreated on the 1632fly while the VNC server is active. If missing, it will default 1633to denying access. 1634 1635@item sasl 1636 1637Require that the client use SASL to authenticate with the VNC server. 1638The exact choice of authentication method used is controlled from the 1639system / user's SASL configuration file for the 'qemu' service. This 1640is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1641unprivileged user, an environment variable SASL_CONF_PATH can be used 1642to make it search alternate locations for the service config. 1643While some SASL auth methods can also provide data encryption (eg GSSAPI), 1644it is recommended that SASL always be combined with the 'tls' and 1645'x509' settings to enable use of SSL and server certificates. This 1646ensures a data encryption preventing compromise of authentication 1647credentials. See the @ref{vnc_security} section for details on using 1648SASL authentication. 1649 1650@item sasl-authz=@var{ID} 1651 1652Provides the ID of the QAuthZ authorization object against which 1653the client's SASL username will validated. This object is 1654only resolved at time of use, so can be deleted and recreated on the 1655fly while the VNC server is active. If missing, it will default 1656to denying access. 1657 1658@item acl 1659 1660Legacy method for enabling authorization of clients against the 1661x509 distinguished name and SASL username. It results in the creation 1662of two @code{authz-list} objects with IDs of @code{vnc.username} and 1663@code{vnc.x509dname}. The rules for these objects must be configured 1664with the HMP ACL commands. 1665 1666This option is deprecated and should no longer be used. The new 1667@option{sasl-authz} and @option{tls-authz} options are a 1668replacement. 1669 1670@item lossy 1671 1672Enable lossy compression methods (gradient, JPEG, ...). If this 1673option is set, VNC client may receive lossy framebuffer updates 1674depending on its encoding settings. Enabling this option can save 1675a lot of bandwidth at the expense of quality. 1676 1677@item non-adaptive 1678 1679Disable adaptive encodings. Adaptive encodings are enabled by default. 1680An adaptive encoding will try to detect frequently updated screen regions, 1681and send updates in these regions using a lossy encoding (like JPEG). 1682This can be really helpful to save bandwidth when playing videos. Disabling 1683adaptive encodings restores the original static behavior of encodings 1684like Tight. 1685 1686@item share=[allow-exclusive|force-shared|ignore] 1687 1688Set display sharing policy. 'allow-exclusive' allows clients to ask 1689for exclusive access. As suggested by the rfb spec this is 1690implemented by dropping other connections. Connecting multiple 1691clients in parallel requires all clients asking for a shared session 1692(vncviewer: -shared switch). This is the default. 'force-shared' 1693disables exclusive client access. Useful for shared desktop sessions, 1694where you don't want someone forgetting specify -shared disconnect 1695everybody else. 'ignore' completely ignores the shared flag and 1696allows everybody connect unconditionally. Doesn't conform to the rfb 1697spec but is traditional QEMU behavior. 1698 1699@item key-delay-ms 1700 1701Set keyboard delay, for key down and key up events, in milliseconds. 1702Default is 10. Keyboards are low-bandwidth devices, so this slowdown 1703can help the device and guest to keep up and not lose events in case 1704events are arriving in bulk. Possible causes for the latter are flaky 1705network connections, or scripts for automated testing. 1706 1707@end table 1708ETEXI 1709 1710STEXI 1711@end table 1712ETEXI 1713ARCHHEADING(, QEMU_ARCH_I386) 1714 1715ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1716STEXI 1717@table @option 1718ETEXI 1719 1720DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1721 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1722 QEMU_ARCH_I386) 1723STEXI 1724@item -win2k-hack 1725@findex -win2k-hack 1726Use it when installing Windows 2000 to avoid a disk full bug. After 1727Windows 2000 is installed, you no longer need this option (this option 1728slows down the IDE transfers). 1729ETEXI 1730 1731DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1732 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1733 QEMU_ARCH_I386) 1734STEXI 1735@item -no-fd-bootchk 1736@findex -no-fd-bootchk 1737Disable boot signature checking for floppy disks in BIOS. May 1738be needed to boot from old floppy disks. 1739ETEXI 1740 1741DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1742 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1743STEXI 1744@item -no-acpi 1745@findex -no-acpi 1746Disable ACPI (Advanced Configuration and Power Interface) support. Use 1747it if your guest OS complains about ACPI problems (PC target machine 1748only). 1749ETEXI 1750 1751DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1752 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1753STEXI 1754@item -no-hpet 1755@findex -no-hpet 1756Disable HPET support. 1757ETEXI 1758 1759DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1760 "-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" 1761 " ACPI table description\n", QEMU_ARCH_I386) 1762STEXI 1763@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}]...] 1764@findex -acpitable 1765Add ACPI table with specified header fields and context from specified files. 1766For file=, take whole ACPI table from the specified files, including all 1767ACPI headers (possible overridden by other options). 1768For data=, only data 1769portion of the table is used, all header information is specified in the 1770command line. 1771If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1772fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1773to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1774spec. 1775ETEXI 1776 1777DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1778 "-smbios file=binary\n" 1779 " load SMBIOS entry from binary file\n" 1780 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1781 " [,uefi=on|off]\n" 1782 " specify SMBIOS type 0 fields\n" 1783 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1784 " [,uuid=uuid][,sku=str][,family=str]\n" 1785 " specify SMBIOS type 1 fields\n" 1786 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1787 " [,asset=str][,location=str]\n" 1788 " specify SMBIOS type 2 fields\n" 1789 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1790 " [,sku=str]\n" 1791 " specify SMBIOS type 3 fields\n" 1792 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1793 " [,asset=str][,part=str]\n" 1794 " specify SMBIOS type 4 fields\n" 1795 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1796 " [,asset=str][,part=str][,speed=%d]\n" 1797 " specify SMBIOS type 17 fields\n", 1798 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1799STEXI 1800@item -smbios file=@var{binary} 1801@findex -smbios 1802Load SMBIOS entry from binary file. 1803 1804@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1805Specify SMBIOS type 0 fields 1806 1807@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}] 1808Specify SMBIOS type 1 fields 1809 1810@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}] 1811Specify SMBIOS type 2 fields 1812 1813@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1814Specify SMBIOS type 3 fields 1815 1816@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1817Specify SMBIOS type 4 fields 1818 1819@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}] 1820Specify SMBIOS type 17 fields 1821ETEXI 1822 1823STEXI 1824@end table 1825ETEXI 1826DEFHEADING() 1827 1828DEFHEADING(Network options:) 1829STEXI 1830@table @option 1831ETEXI 1832 1833DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1834#ifdef CONFIG_SLIRP 1835 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 1836 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 1837 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1838 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n" 1839 " [,tftp=dir][,tftp-server-name=name][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1840#ifndef _WIN32 1841 "[,smb=dir[,smbserver=addr]]\n" 1842#endif 1843 " configure a user mode network backend with ID 'str',\n" 1844 " its DHCP server and optional services\n" 1845#endif 1846#ifdef _WIN32 1847 "-netdev tap,id=str,ifname=name\n" 1848 " configure a host TAP network backend with ID 'str'\n" 1849#else 1850 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1851 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1852 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1853 " [,poll-us=n]\n" 1854 " configure a host TAP network backend with ID 'str'\n" 1855 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1856 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1857 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1858 " to deconfigure it\n" 1859 " use '[down]script=no' to disable script execution\n" 1860 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1861 " configure it\n" 1862 " use 'fd=h' to connect to an already opened TAP interface\n" 1863 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1864 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1865 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1866 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1867 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1868 " use vhost=on to enable experimental in kernel accelerator\n" 1869 " (only has effect for virtio guests which use MSIX)\n" 1870 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1871 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1872 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1873 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1874 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 1875 " spent on busy polling for vhost net\n" 1876 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1877 " configure a host TAP network backend with ID 'str' that is\n" 1878 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1879 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1880#endif 1881#ifdef __linux__ 1882 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1883 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1884 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1885 " [,rxcookie=rxcookie][,offset=offset]\n" 1886 " configure a network backend with ID 'str' connected to\n" 1887 " an Ethernet over L2TPv3 pseudowire.\n" 1888 " Linux kernel 3.3+ as well as most routers can talk\n" 1889 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1890 " VM to a router and even VM to Host. It is a nearly-universal\n" 1891 " standard (RFC3391). Note - this implementation uses static\n" 1892 " pre-configured tunnels (same as the Linux kernel).\n" 1893 " use 'src=' to specify source address\n" 1894 " use 'dst=' to specify destination address\n" 1895 " use 'udp=on' to specify udp encapsulation\n" 1896 " use 'srcport=' to specify source udp port\n" 1897 " use 'dstport=' to specify destination udp port\n" 1898 " use 'ipv6=on' to force v6\n" 1899 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1900 " well as a weak security measure\n" 1901 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1902 " use 'txcookie=0x012345678' to specify a txcookie\n" 1903 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1904 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1905 " use 'pincounter=on' to work around broken counter handling in peer\n" 1906 " use 'offset=X' to add an extra offset between header and data\n" 1907#endif 1908 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1909 " configure a network backend to connect to another network\n" 1910 " using a socket connection\n" 1911 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1912 " configure a network backend to connect to a multicast maddr and port\n" 1913 " use 'localaddr=addr' to specify the host address to send packets from\n" 1914 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1915 " configure a network backend to connect to another network\n" 1916 " using an UDP tunnel\n" 1917#ifdef CONFIG_VDE 1918 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1919 " configure a network backend to connect to port 'n' of a vde switch\n" 1920 " running on host and listening for incoming connections on 'socketpath'.\n" 1921 " Use group 'groupname' and mode 'octalmode' to change default\n" 1922 " ownership and permissions for communication port.\n" 1923#endif 1924#ifdef CONFIG_NETMAP 1925 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1926 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1927 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1928 " netmap device, defaults to '/dev/netmap')\n" 1929#endif 1930#ifdef CONFIG_POSIX 1931 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 1932 " configure a vhost-user network, backed by a chardev 'dev'\n" 1933#endif 1934 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n" 1935 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL) 1936DEF("nic", HAS_ARG, QEMU_OPTION_nic, 1937 "-nic [tap|bridge|" 1938#ifdef CONFIG_SLIRP 1939 "user|" 1940#endif 1941#ifdef __linux__ 1942 "l2tpv3|" 1943#endif 1944#ifdef CONFIG_VDE 1945 "vde|" 1946#endif 1947#ifdef CONFIG_NETMAP 1948 "netmap|" 1949#endif 1950#ifdef CONFIG_POSIX 1951 "vhost-user|" 1952#endif 1953 "socket][,option][,...][mac=macaddr]\n" 1954 " initialize an on-board / default host NIC (using MAC address\n" 1955 " macaddr) and connect it to the given host network backend\n" 1956 "-nic none use it alone to have zero network devices (the default is to\n" 1957 " provided a 'user' network connection)\n", 1958 QEMU_ARCH_ALL) 1959DEF("net", HAS_ARG, QEMU_OPTION_net, 1960 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1961 " configure or create an on-board (or machine default) NIC and\n" 1962 " connect it to hub 0 (please use -nic unless you need a hub)\n" 1963 "-net [" 1964#ifdef CONFIG_SLIRP 1965 "user|" 1966#endif 1967 "tap|" 1968 "bridge|" 1969#ifdef CONFIG_VDE 1970 "vde|" 1971#endif 1972#ifdef CONFIG_NETMAP 1973 "netmap|" 1974#endif 1975 "socket][,option][,option][,...]\n" 1976 " old way to initialize a host network interface\n" 1977 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 1978STEXI 1979@item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn] 1980@findex -nic 1981This option is a shortcut for configuring both the on-board (default) guest 1982NIC hardware and the host network backend in one go. The host backend options 1983are the same as with the corresponding @option{-netdev} options below. 1984The guest NIC model can be set with @option{model=@var{modelname}}. 1985Use @option{model=help} to list the available device types. 1986The hardware MAC address can be set with @option{mac=@var{macaddr}}. 1987 1988The following two example do exactly the same, to show how @option{-nic} can 1989be used to shorten the command line length (note that the e1000 is the default 1990on i386, so the @option{model=e1000} parameter could even be omitted here, too): 1991@example 1992qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32 1993qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32 1994@end example 1995 1996@item -nic none 1997Indicate that no network devices should be configured. It is used to override 1998the default configuration (default NIC with ``user'' host network backend) 1999which is activated if no other networking options are provided. 2000 2001@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 2002@findex -netdev 2003Configure user mode host network backend which requires no administrator 2004privilege to run. Valid options are: 2005 2006@table @option 2007@item id=@var{id} 2008Assign symbolic name for use in monitor commands. 2009 2010@item ipv4=on|off and ipv6=on|off 2011Specify that either IPv4 or IPv6 must be enabled. If neither is specified 2012both protocols are enabled. 2013 2014@item net=@var{addr}[/@var{mask}] 2015Set IP network address the guest will see. Optionally specify the netmask, 2016either in the form a.b.c.d or as number of valid top-most bits. Default is 201710.0.2.0/24. 2018 2019@item host=@var{addr} 2020Specify the guest-visible address of the host. Default is the 2nd IP in the 2021guest network, i.e. x.x.x.2. 2022 2023@item ipv6-net=@var{addr}[/@var{int}] 2024Set IPv6 network address the guest will see (default is fec0::/64). The 2025network prefix is given in the usual hexadecimal IPv6 address 2026notation. The prefix size is optional, and is given as the number of 2027valid top-most bits (default is 64). 2028 2029@item ipv6-host=@var{addr} 2030Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 2031the guest network, i.e. xxxx::2. 2032 2033@item restrict=on|off 2034If this option is enabled, the guest will be isolated, i.e. it will not be 2035able to contact the host and no guest IP packets will be routed over the host 2036to the outside. This option does not affect any explicitly set forwarding rules. 2037 2038@item hostname=@var{name} 2039Specifies the client hostname reported by the built-in DHCP server. 2040 2041@item dhcpstart=@var{addr} 2042Specify the first of the 16 IPs the built-in DHCP server can assign. Default 2043is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 2044 2045@item dns=@var{addr} 2046Specify the guest-visible address of the virtual nameserver. The address must 2047be different from the host address. Default is the 3rd IP in the guest network, 2048i.e. x.x.x.3. 2049 2050@item ipv6-dns=@var{addr} 2051Specify the guest-visible address of the IPv6 virtual nameserver. The address 2052must be different from the host address. Default is the 3rd IP in the guest 2053network, i.e. xxxx::3. 2054 2055@item dnssearch=@var{domain} 2056Provides an entry for the domain-search list sent by the built-in 2057DHCP server. More than one domain suffix can be transmitted by specifying 2058this option multiple times. If supported, this will cause the guest to 2059automatically try to append the given domain suffix(es) in case a domain name 2060can not be resolved. 2061 2062Example: 2063@example 2064qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org 2065@end example 2066 2067@item domainname=@var{domain} 2068Specifies the client domain name reported by the built-in DHCP server. 2069 2070@item tftp=@var{dir} 2071When using the user mode network stack, activate a built-in TFTP 2072server. The files in @var{dir} will be exposed as the root of a TFTP server. 2073The TFTP client on the guest must be configured in binary mode (use the command 2074@code{bin} of the Unix TFTP client). 2075 2076@item tftp-server-name=@var{name} 2077In BOOTP reply, broadcast @var{name} as the "TFTP server name" (RFC2132 option 207866). This can be used to advise the guest to load boot files or configurations 2079from a different server than the host address. 2080 2081@item bootfile=@var{file} 2082When using the user mode network stack, broadcast @var{file} as the BOOTP 2083filename. In conjunction with @option{tftp}, this can be used to network boot 2084a guest from a local directory. 2085 2086Example (using pxelinux): 2087@example 2088qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \ 2089 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2090@end example 2091 2092@item smb=@var{dir}[,smbserver=@var{addr}] 2093When using the user mode network stack, activate a built-in SMB 2094server so that Windows OSes can access to the host files in @file{@var{dir}} 2095transparently. The IP address of the SMB server can be set to @var{addr}. By 2096default the 4th IP in the guest network is used, i.e. x.x.x.4. 2097 2098In the guest Windows OS, the line: 2099@example 210010.0.2.4 smbserver 2101@end example 2102must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2103or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2104 2105Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2106 2107Note that a SAMBA server must be installed on the host OS. 2108 2109@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2110Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2111the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2112@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2113given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2114be bound to a specific host interface. If no connection type is set, TCP is 2115used. This option can be given multiple times. 2116 2117For example, to redirect host X11 connection from screen 1 to guest 2118screen 0, use the following: 2119 2120@example 2121# on the host 2122qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 2123# this host xterm should open in the guest X11 server 2124xterm -display :1 2125@end example 2126 2127To redirect telnet connections from host port 5555 to telnet port on 2128the guest, use the following: 2129 2130@example 2131# on the host 2132qemu-system-i386 -nic user,hostfwd=tcp::5555-:23 2133telnet localhost 5555 2134@end example 2135 2136Then when you use on the host @code{telnet localhost 5555}, you 2137connect to the guest telnet server. 2138 2139@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2140@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2141Forward guest TCP connections to the IP address @var{server} on port @var{port} 2142to the character device @var{dev} or to a program executed by @var{cmd:command} 2143which gets spawned for each connection. This option can be given multiple times. 2144 2145You can either use a chardev directly and have that one used throughout QEMU's 2146lifetime, like in the following example: 2147 2148@example 2149# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2150# the guest accesses it 2151qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 2152@end example 2153 2154Or you can execute a command on every TCP connection established by the guest, 2155so that QEMU behaves similar to an inetd process for that virtual server: 2156 2157@example 2158# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2159# and connect the TCP stream to its stdin/stdout 2160qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2161@end example 2162 2163@end table 2164 2165@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2166Configure a host TAP network backend with ID @var{id}. 2167 2168Use the network script @var{file} to configure it and the network script 2169@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2170automatically provides one. The default network configure script is 2171@file{/etc/qemu-ifup} and the default network deconfigure script is 2172@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2173to disable script execution. 2174 2175If running QEMU as an unprivileged user, use the network helper 2176@var{helper} to configure the TAP interface and attach it to the bridge. 2177The default network helper executable is @file{/path/to/qemu-bridge-helper} 2178and the default bridge device is @file{br0}. 2179 2180@option{fd}=@var{h} can be used to specify the handle of an already 2181opened host TAP interface. 2182 2183Examples: 2184 2185@example 2186#launch a QEMU instance with the default network script 2187qemu-system-i386 linux.img -nic tap 2188@end example 2189 2190@example 2191#launch a QEMU instance with two NICs, each one connected 2192#to a TAP device 2193qemu-system-i386 linux.img \ 2194 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \ 2195 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1 2196@end example 2197 2198@example 2199#launch a QEMU instance with the default network helper to 2200#connect a TAP device to bridge br0 2201qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \ 2202 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper" 2203@end example 2204 2205@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2206Connect a host TAP network interface to a host bridge device. 2207 2208Use the network helper @var{helper} to configure the TAP interface and 2209attach it to the bridge. The default network helper executable is 2210@file{/path/to/qemu-bridge-helper} and the default bridge 2211device is @file{br0}. 2212 2213Examples: 2214 2215@example 2216#launch a QEMU instance with the default network helper to 2217#connect a TAP device to bridge br0 2218qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1 2219@end example 2220 2221@example 2222#launch a QEMU instance with the default network helper to 2223#connect a TAP device to bridge qemubr0 2224qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1 2225@end example 2226 2227@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2228 2229This host network backend can be used to connect the guest's network to 2230another QEMU virtual machine using a TCP socket connection. If @option{listen} 2231is specified, QEMU waits for incoming connections on @var{port} 2232(@var{host} is optional). @option{connect} is used to connect to 2233another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2234specifies an already opened TCP socket. 2235 2236Example: 2237@example 2238# launch a first QEMU instance 2239qemu-system-i386 linux.img \ 2240 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2241 -netdev socket,id=n1,listen=:1234 2242# connect the network of this instance to the network of the first instance 2243qemu-system-i386 linux.img \ 2244 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2245 -netdev socket,id=n2,connect=127.0.0.1:1234 2246@end example 2247 2248@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2249 2250Configure a socket host network backend to share the guest's network traffic 2251with another QEMU virtual machines using a UDP multicast socket, effectively 2252making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. 2253NOTES: 2254@enumerate 2255@item 2256Several QEMU can be running on different hosts and share same bus (assuming 2257correct multicast setup for these hosts). 2258@item 2259mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2260@url{http://user-mode-linux.sf.net}. 2261@item 2262Use @option{fd=h} to specify an already opened UDP multicast socket. 2263@end enumerate 2264 2265Example: 2266@example 2267# launch one QEMU instance 2268qemu-system-i386 linux.img \ 2269 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2270 -netdev socket,id=n1,mcast=230.0.0.1:1234 2271# launch another QEMU instance on same "bus" 2272qemu-system-i386 linux.img \ 2273 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2274 -netdev socket,id=n2,mcast=230.0.0.1:1234 2275# launch yet another QEMU instance on same "bus" 2276qemu-system-i386 linux.img \ 2277 -device e1000,netdev=n3,mac=52:54:00:12:34:58 \ 2278 -netdev socket,id=n3,mcast=230.0.0.1:1234 2279@end example 2280 2281Example (User Mode Linux compat.): 2282@example 2283# launch QEMU instance (note mcast address selected is UML's default) 2284qemu-system-i386 linux.img \ 2285 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2286 -netdev socket,id=n1,mcast=239.192.168.1:1102 2287# launch UML 2288/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2289@end example 2290 2291Example (send packets from host's 1.2.3.4): 2292@example 2293qemu-system-i386 linux.img \ 2294 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2295 -netdev socket,id=n1,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2296@end example 2297 2298@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}] 2299Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a 2300popular protocol to transport Ethernet (and other Layer 2) data frames between 2301two systems. It is present in routers, firewalls and the Linux kernel 2302(from version 3.3 onwards). 2303 2304This transport allows a VM to communicate to another VM, router or firewall directly. 2305 2306@table @option 2307@item src=@var{srcaddr} 2308 source address (mandatory) 2309@item dst=@var{dstaddr} 2310 destination address (mandatory) 2311@item udp 2312 select udp encapsulation (default is ip). 2313@item srcport=@var{srcport} 2314 source udp port. 2315@item dstport=@var{dstport} 2316 destination udp port. 2317@item ipv6 2318 force v6, otherwise defaults to v4. 2319@item rxcookie=@var{rxcookie} 2320@itemx txcookie=@var{txcookie} 2321 Cookies are a weak form of security in the l2tpv3 specification. 2322Their function is mostly to prevent misconfiguration. By default they are 32 2323bit. 2324@item cookie64 2325 Set cookie size to 64 bit instead of the default 32 2326@item counter=off 2327 Force a 'cut-down' L2TPv3 with no counter as in 2328draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2329@item pincounter=on 2330 Work around broken counter handling in peer. This may also help on 2331networks which have packet reorder. 2332@item offset=@var{offset} 2333 Add an extra offset between header and data 2334@end table 2335 2336For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2337on the remote Linux host 1.2.3.4: 2338@example 2339# Setup tunnel on linux host using raw ip as encapsulation 2340# on 1.2.3.4 2341ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2342 encap udp udp_sport 16384 udp_dport 16384 2343ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2344 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2345ifconfig vmtunnel0 mtu 1500 2346ifconfig vmtunnel0 up 2347brctl addif br-lan vmtunnel0 2348 2349 2350# on 4.3.2.1 2351# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2352 2353qemu-system-i386 linux.img -device e1000,netdev=n1 \ 2354 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2355 2356@end example 2357 2358@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2359Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and 2360listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2361and MODE @var{octalmode} to change default ownership and permissions for 2362communication port. This option is only available if QEMU has been compiled 2363with vde support enabled. 2364 2365Example: 2366@example 2367# launch vde switch 2368vde_switch -F -sock /tmp/myswitch 2369# launch QEMU instance 2370qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch 2371@end example 2372 2373@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2374 2375Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2376be a unix domain socket backed one. The vhost-user uses a specifically defined 2377protocol to pass vhost ioctl replacement messages to an application on the other 2378end of the socket. On non-MSIX guests, the feature can be forced with 2379@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2380be created for multiqueue vhost-user. 2381 2382Example: 2383@example 2384qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2385 -numa node,memdev=mem \ 2386 -chardev socket,id=chr0,path=/path/to/socket \ 2387 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2388 -device virtio-net-pci,netdev=net0 2389@end example 2390 2391@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}] 2392 2393Create a hub port on the emulated hub with ID @var{hubid}. 2394 2395The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a 2396single netdev. Alternatively, you can also connect the hubport to another 2397netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option. 2398 2399@item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2400@findex -net 2401Legacy option to configure or create an on-board (or machine default) Network 2402Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. 2403the default hub), or to the netdev @var{nd}. 2404The NIC is an e1000 by default on the PC target. Optionally, the MAC address 2405can be changed to @var{mac}, the device address set to @var{addr} (PCI cards 2406only), and a @var{name} can be assigned for use in monitor commands. 2407Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2408that the card should have; this option currently only affects virtio cards; set 2409@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2410NIC is created. QEMU can emulate several different models of network card. 2411Use @code{-net nic,model=help} for a list of available devices for your target. 2412 2413@item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}] 2414Configure a host network backend (with the options corresponding to the same 2415@option{-netdev} option) and connect it to the emulated hub 0 (the default 2416hub). Use @var{name} to specify the name of the hub port. 2417ETEXI 2418 2419STEXI 2420@end table 2421ETEXI 2422DEFHEADING() 2423 2424DEFHEADING(Character device options:) 2425 2426DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2427 "-chardev help\n" 2428 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2429 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2430 " [,server][,nowait][,telnet][,websocket][,reconnect=seconds][,mux=on|off]\n" 2431 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID][,tls-authz=ID] (tcp)\n" 2432 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,websocket][,reconnect=seconds]\n" 2433 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2434 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2435 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2436 " [,logfile=PATH][,logappend=on|off]\n" 2437 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2438 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2439 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2440 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2441 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2442 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2443#ifdef _WIN32 2444 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2445 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2446#else 2447 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2448 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2449#endif 2450#ifdef CONFIG_BRLAPI 2451 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2452#endif 2453#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2454 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2455 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2456 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2457#endif 2458#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2459 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2460 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2461#endif 2462#if defined(CONFIG_SPICE) 2463 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2464 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2465#endif 2466 , QEMU_ARCH_ALL 2467) 2468 2469STEXI 2470 2471The general form of a character device option is: 2472@table @option 2473@item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}] 2474@findex -chardev 2475Backend is one of: 2476@option{null}, 2477@option{socket}, 2478@option{udp}, 2479@option{msmouse}, 2480@option{vc}, 2481@option{ringbuf}, 2482@option{file}, 2483@option{pipe}, 2484@option{console}, 2485@option{serial}, 2486@option{pty}, 2487@option{stdio}, 2488@option{braille}, 2489@option{tty}, 2490@option{parallel}, 2491@option{parport}, 2492@option{spicevmc}, 2493@option{spiceport}. 2494The specific backend will determine the applicable options. 2495 2496Use @code{-chardev help} to print all available chardev backend types. 2497 2498All devices must have an id, which can be any string up to 127 characters long. 2499It is used to uniquely identify this device in other command line directives. 2500 2501A character device may be used in multiplexing mode by multiple front-ends. 2502Specify @option{mux=on} to enable this mode. 2503A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2504backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2505If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2506create a multiplexer with your specified ID, and you can then configure multiple 2507front ends to use that chardev ID for their input/output. Up to four different 2508front ends can be connected to a single multiplexed chardev. (Without 2509multiplexing enabled, a chardev can only be used by a single front end.) 2510For instance you could use this to allow a single stdio chardev to be used by 2511two serial ports and the QEMU monitor: 2512 2513@example 2514-chardev stdio,mux=on,id=char0 \ 2515-mon chardev=char0,mode=readline \ 2516-serial chardev:char0 \ 2517-serial chardev:char0 2518@end example 2519 2520You can have more than one multiplexer in a system configuration; for instance 2521you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2522multiplexed between the QEMU monitor and a parallel port: 2523 2524@example 2525-chardev stdio,mux=on,id=char0 \ 2526-mon chardev=char0,mode=readline \ 2527-parallel chardev:char0 \ 2528-chardev tcp,...,mux=on,id=char1 \ 2529-serial chardev:char1 \ 2530-serial chardev:char1 2531@end example 2532 2533When you're using a multiplexed character device, some escape sequences are 2534interpreted in the input. @xref{mux_keys, Keys in the character backend 2535multiplexer}. 2536 2537Note that some other command line options may implicitly create multiplexed 2538character backends; for instance @option{-serial mon:stdio} creates a 2539multiplexed stdio backend connected to the serial port and the QEMU monitor, 2540and @option{-nographic} also multiplexes the console and the monitor to 2541stdio. 2542 2543There is currently no support for multiplexing in the other direction 2544(where a single QEMU front end takes input and output from multiple chardevs). 2545 2546Every backend supports the @option{logfile} option, which supplies the path 2547to a file to record all data transmitted via the backend. The @option{logappend} 2548option controls whether the log file will be truncated or appended to when 2549opened. 2550 2551@end table 2552 2553The available backends are: 2554 2555@table @option 2556@item -chardev null,id=@var{id} 2557A void device. This device will not emit any data, and will drop any data it 2558receives. The null backend does not take any options. 2559 2560@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,websocket][,reconnect=@var{seconds}][,tls-creds=@var{id}][,tls-authz=@var{id}] 2561 2562Create a two-way stream socket, which can be either a TCP or a unix socket. A 2563unix socket will be created if @option{path} is specified. Behaviour is 2564undefined if TCP options are specified for a unix socket. 2565 2566@option{server} specifies that the socket shall be a listening socket. 2567 2568@option{nowait} specifies that QEMU should not block waiting for a client to 2569connect to a listening socket. 2570 2571@option{telnet} specifies that traffic on the socket should interpret telnet 2572escape sequences. 2573 2574@option{websocket} specifies that the socket uses WebSocket protocol for 2575communication. 2576 2577@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2578the remote end goes away. qemu will delay this many seconds and then attempt 2579to reconnect. Zero disables reconnecting, and is the default. 2580 2581@option{tls-creds} requests enablement of the TLS protocol for encryption, 2582and specifies the id of the TLS credentials to use for the handshake. The 2583credentials must be previously created with the @option{-object tls-creds} 2584argument. 2585 2586@option{tls-auth} provides the ID of the QAuthZ authorization object against 2587which the client's x509 distinguished name will be validated. This object is 2588only resolved at time of use, so can be deleted and recreated on the fly 2589while the chardev server is active. If missing, it will default to denying 2590access. 2591 2592TCP and unix socket options are given below: 2593 2594@table @option 2595 2596@item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay] 2597 2598@option{host} for a listening socket specifies the local address to be bound. 2599For a connecting socket species the remote host to connect to. @option{host} is 2600optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2601 2602@option{port} for a listening socket specifies the local port to be bound. For a 2603connecting socket specifies the port on the remote host to connect to. 2604@option{port} can be given as either a port number or a service name. 2605@option{port} is required. 2606 2607@option{to} is only relevant to listening sockets. If it is specified, and 2608@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2609to and including @option{to} until it succeeds. @option{to} must be specified 2610as a port number. 2611 2612@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2613If neither is specified the socket may use either protocol. 2614 2615@option{nodelay} disables the Nagle algorithm. 2616 2617@item unix options: path=@var{path} 2618 2619@option{path} specifies the local path of the unix socket. @option{path} is 2620required. 2621 2622@end table 2623 2624@item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6] 2625 2626Sends all traffic from the guest to a remote host over UDP. 2627 2628@option{host} specifies the remote host to connect to. If not specified it 2629defaults to @code{localhost}. 2630 2631@option{port} specifies the port on the remote host to connect to. @option{port} 2632is required. 2633 2634@option{localaddr} specifies the local address to bind to. If not specified it 2635defaults to @code{0.0.0.0}. 2636 2637@option{localport} specifies the local port to bind to. If not specified any 2638available local port will be used. 2639 2640@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2641If neither is specified the device may use either protocol. 2642 2643@item -chardev msmouse,id=@var{id} 2644 2645Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2646take any options. 2647 2648@item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]] 2649 2650Connect to a QEMU text console. @option{vc} may optionally be given a specific 2651size. 2652 2653@option{width} and @option{height} specify the width and height respectively of 2654the console, in pixels. 2655 2656@option{cols} and @option{rows} specify that the console be sized to fit a text 2657console with the given dimensions. 2658 2659@item -chardev ringbuf,id=@var{id}[,size=@var{size}] 2660 2661Create a ring buffer with fixed size @option{size}. 2662@var{size} must be a power of two and defaults to @code{64K}. 2663 2664@item -chardev file,id=@var{id},path=@var{path} 2665 2666Log all traffic received from the guest to a file. 2667 2668@option{path} specifies the path of the file to be opened. This file will be 2669created if it does not already exist, and overwritten if it does. @option{path} 2670is required. 2671 2672@item -chardev pipe,id=@var{id},path=@var{path} 2673 2674Create a two-way connection to the guest. The behaviour differs slightly between 2675Windows hosts and other hosts: 2676 2677On Windows, a single duplex pipe will be created at 2678@file{\\.pipe\@option{path}}. 2679 2680On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2681@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2682received by the guest. Data written by the guest can be read from 2683@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2684be present. 2685 2686@option{path} forms part of the pipe path as described above. @option{path} is 2687required. 2688 2689@item -chardev console,id=@var{id} 2690 2691Send traffic from the guest to QEMU's standard output. @option{console} does not 2692take any options. 2693 2694@option{console} is only available on Windows hosts. 2695 2696@item -chardev serial,id=@var{id},path=@option{path} 2697 2698Send traffic from the guest to a serial device on the host. 2699 2700On Unix hosts serial will actually accept any tty device, 2701not only serial lines. 2702 2703@option{path} specifies the name of the serial device to open. 2704 2705@item -chardev pty,id=@var{id} 2706 2707Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2708not take any options. 2709 2710@option{pty} is not available on Windows hosts. 2711 2712@item -chardev stdio,id=@var{id}[,signal=on|off] 2713Connect to standard input and standard output of the QEMU process. 2714 2715@option{signal} controls if signals are enabled on the terminal, that includes 2716exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2717default, use @option{signal=off} to disable it. 2718 2719@item -chardev braille,id=@var{id} 2720 2721Connect to a local BrlAPI server. @option{braille} does not take any options. 2722 2723@item -chardev tty,id=@var{id},path=@var{path} 2724 2725@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2726DragonFlyBSD hosts. It is an alias for @option{serial}. 2727 2728@option{path} specifies the path to the tty. @option{path} is required. 2729 2730@item -chardev parallel,id=@var{id},path=@var{path} 2731@itemx -chardev parport,id=@var{id},path=@var{path} 2732 2733@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2734 2735Connect to a local parallel port. 2736 2737@option{path} specifies the path to the parallel port device. @option{path} is 2738required. 2739 2740@item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name} 2741 2742@option{spicevmc} is only available when spice support is built in. 2743 2744@option{debug} debug level for spicevmc 2745 2746@option{name} name of spice channel to connect to 2747 2748Connect to a spice virtual machine channel, such as vdiport. 2749 2750@item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name} 2751 2752@option{spiceport} is only available when spice support is built in. 2753 2754@option{debug} debug level for spicevmc 2755 2756@option{name} name of spice port to connect to 2757 2758Connect to a spice port, allowing a Spice client to handle the traffic 2759identified by a name (preferably a fqdn). 2760ETEXI 2761 2762STEXI 2763@end table 2764ETEXI 2765DEFHEADING() 2766 2767DEFHEADING(Bluetooth(R) options:) 2768STEXI 2769@table @option 2770ETEXI 2771 2772DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2773 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2774 "-bt hci,host[:id]\n" \ 2775 " use host's HCI with the given name\n" \ 2776 "-bt hci[,vlan=n]\n" \ 2777 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2778 "-bt vhci[,vlan=n]\n" \ 2779 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2780 "-bt device:dev[,vlan=n]\n" \ 2781 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2782 QEMU_ARCH_ALL) 2783STEXI 2784@item -bt hci[...] 2785@findex -bt 2786Defines the function of the corresponding Bluetooth HCI. -bt options 2787are matched with the HCIs present in the chosen machine type. For 2788example when emulating a machine with only one HCI built into it, only 2789the first @code{-bt hci[...]} option is valid and defines the HCI's 2790logic. The Transport Layer is decided by the machine type. Currently 2791the machines @code{n800} and @code{n810} have one HCI and all other 2792machines have none. 2793 2794Note: This option and the whole bluetooth subsystem is considered as deprecated. 2795If you still use it, please send a mail to @email{qemu-devel@@nongnu.org} where 2796you describe your usecase. 2797 2798@anchor{bt-hcis} 2799The following three types are recognized: 2800 2801@table @option 2802@item -bt hci,null 2803(default) The corresponding Bluetooth HCI assumes no internal logic 2804and will not respond to any HCI commands or emit events. 2805 2806@item -bt hci,host[:@var{id}] 2807(@code{bluez} only) The corresponding HCI passes commands / events 2808to / from the physical HCI identified by the name @var{id} (default: 2809@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2810capable systems like Linux. 2811 2812@item -bt hci[,vlan=@var{n}] 2813Add a virtual, standard HCI that will participate in the Bluetooth 2814scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2815VLANs, devices inside a bluetooth network @var{n} can only communicate 2816with other devices in the same network (scatternet). 2817@end table 2818 2819@item -bt vhci[,vlan=@var{n}] 2820(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2821to the host bluetooth stack instead of to the emulated target. This 2822allows the host and target machines to participate in a common scatternet 2823and communicate. Requires the Linux @code{vhci} driver installed. Can 2824be used as following: 2825 2826@example 2827qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2828@end example 2829 2830@item -bt device:@var{dev}[,vlan=@var{n}] 2831Emulate a bluetooth device @var{dev} and place it in network @var{n} 2832(default @code{0}). QEMU can only emulate one type of bluetooth devices 2833currently: 2834 2835@table @option 2836@item keyboard 2837Virtual wireless keyboard implementing the HIDP bluetooth profile. 2838@end table 2839ETEXI 2840 2841STEXI 2842@end table 2843ETEXI 2844DEFHEADING() 2845 2846#ifdef CONFIG_TPM 2847DEFHEADING(TPM device options:) 2848 2849DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2850 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2851 " use path to provide path to a character device; default is /dev/tpm0\n" 2852 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2853 " not provided it will be searched for in /sys/class/misc/tpm?/device\n" 2854 "-tpmdev emulator,id=id,chardev=dev\n" 2855 " configure the TPM device using chardev backend\n", 2856 QEMU_ARCH_ALL) 2857STEXI 2858 2859The general form of a TPM device option is: 2860@table @option 2861 2862@item -tpmdev @var{backend},id=@var{id}[,@var{options}] 2863@findex -tpmdev 2864 2865The specific backend type will determine the applicable options. 2866The @code{-tpmdev} option creates the TPM backend and requires a 2867@code{-device} option that specifies the TPM frontend interface model. 2868 2869Use @code{-tpmdev help} to print all available TPM backend types. 2870 2871@end table 2872 2873The available backends are: 2874 2875@table @option 2876 2877@item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path} 2878 2879(Linux-host only) Enable access to the host's TPM using the passthrough 2880driver. 2881 2882@option{path} specifies the path to the host's TPM device, i.e., on 2883a Linux host this would be @code{/dev/tpm0}. 2884@option{path} is optional and by default @code{/dev/tpm0} is used. 2885 2886@option{cancel-path} specifies the path to the host TPM device's sysfs 2887entry allowing for cancellation of an ongoing TPM command. 2888@option{cancel-path} is optional and by default QEMU will search for the 2889sysfs entry to use. 2890 2891Some notes about using the host's TPM with the passthrough driver: 2892 2893The TPM device accessed by the passthrough driver must not be 2894used by any other application on the host. 2895 2896Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2897the VM's firmware (BIOS/UEFI) will not be able to initialize the 2898TPM again and may therefore not show a TPM-specific menu that would 2899otherwise allow the user to configure the TPM, e.g., allow the user to 2900enable/disable or activate/deactivate the TPM. 2901Further, if TPM ownership is released from within a VM then the host's TPM 2902will get disabled and deactivated. To enable and activate the 2903TPM again afterwards, the host has to be rebooted and the user is 2904required to enter the firmware's menu to enable and activate the TPM. 2905If the TPM is left disabled and/or deactivated most TPM commands will fail. 2906 2907To create a passthrough TPM use the following two options: 2908@example 2909-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2910@end example 2911Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2912@code{tpmdev=tpm0} in the device option. 2913 2914@item -tpmdev emulator,id=@var{id},chardev=@var{dev} 2915 2916(Linux-host only) Enable access to a TPM emulator using Unix domain socket based 2917chardev backend. 2918 2919@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server. 2920 2921To create a TPM emulator backend device with chardev socket backend: 2922@example 2923 2924-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0 2925 2926@end example 2927 2928ETEXI 2929 2930STEXI 2931@end table 2932ETEXI 2933DEFHEADING() 2934 2935#endif 2936 2937DEFHEADING(Linux/Multiboot boot specific:) 2938STEXI 2939 2940When using these options, you can use a given Linux or Multiboot 2941kernel without installing it in the disk image. It can be useful 2942for easier testing of various kernels. 2943 2944@table @option 2945ETEXI 2946 2947DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2948 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2949STEXI 2950@item -kernel @var{bzImage} 2951@findex -kernel 2952Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2953or in multiboot format. 2954ETEXI 2955 2956DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2957 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2958STEXI 2959@item -append @var{cmdline} 2960@findex -append 2961Use @var{cmdline} as kernel command line 2962ETEXI 2963 2964DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2965 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2966STEXI 2967@item -initrd @var{file} 2968@findex -initrd 2969Use @var{file} as initial ram disk. 2970 2971@item -initrd "@var{file1} arg=foo,@var{file2}" 2972 2973This syntax is only available with multiboot. 2974 2975Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2976first module. 2977ETEXI 2978 2979DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2980 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2981STEXI 2982@item -dtb @var{file} 2983@findex -dtb 2984Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2985on boot. 2986ETEXI 2987 2988STEXI 2989@end table 2990ETEXI 2991DEFHEADING() 2992 2993DEFHEADING(Debug/Expert options:) 2994STEXI 2995@table @option 2996ETEXI 2997 2998DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 2999 "-fw_cfg [name=]<name>,file=<file>\n" 3000 " add named fw_cfg entry with contents from file\n" 3001 "-fw_cfg [name=]<name>,string=<str>\n" 3002 " add named fw_cfg entry with contents from string\n", 3003 QEMU_ARCH_ALL) 3004STEXI 3005 3006@item -fw_cfg [name=]@var{name},file=@var{file} 3007@findex -fw_cfg 3008Add named fw_cfg entry with contents from file @var{file}. 3009 3010@item -fw_cfg [name=]@var{name},string=@var{str} 3011Add named fw_cfg entry with contents from string @var{str}. 3012 3013The terminating NUL character of the contents of @var{str} will not be 3014included as part of the fw_cfg item data. To insert contents with 3015embedded NUL characters, you have to use the @var{file} parameter. 3016 3017The fw_cfg entries are passed by QEMU through to the guest. 3018 3019Example: 3020@example 3021 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 3022@end example 3023creates an fw_cfg entry named opt/com.mycompany/blob with contents 3024from ./my_blob.bin. 3025 3026ETEXI 3027 3028DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 3029 "-serial dev redirect the serial port to char device 'dev'\n", 3030 QEMU_ARCH_ALL) 3031STEXI 3032@item -serial @var{dev} 3033@findex -serial 3034Redirect the virtual serial port to host character device 3035@var{dev}. The default device is @code{vc} in graphical mode and 3036@code{stdio} in non graphical mode. 3037 3038This option can be used several times to simulate up to 4 serial 3039ports. 3040 3041Use @code{-serial none} to disable all serial ports. 3042 3043Available character devices are: 3044@table @option 3045@item vc[:@var{W}x@var{H}] 3046Virtual console. Optionally, a width and height can be given in pixel with 3047@example 3048vc:800x600 3049@end example 3050It is also possible to specify width or height in characters: 3051@example 3052vc:80Cx24C 3053@end example 3054@item pty 3055[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3056@item none 3057No device is allocated. 3058@item null 3059void device 3060@item chardev:@var{id} 3061Use a named character device defined with the @code{-chardev} option. 3062@item /dev/XXX 3063[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3064parameters are set according to the emulated ones. 3065@item /dev/parport@var{N} 3066[Linux only, parallel port only] Use host parallel port 3067@var{N}. Currently SPP and EPP parallel port features can be used. 3068@item file:@var{filename} 3069Write output to @var{filename}. No character can be read. 3070@item stdio 3071[Unix only] standard input/output 3072@item pipe:@var{filename} 3073name pipe @var{filename} 3074@item COM@var{n} 3075[Windows only] Use host serial port @var{n} 3076@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3077This implements UDP Net Console. 3078When @var{remote_host} or @var{src_ip} are not specified 3079they default to @code{0.0.0.0}. 3080When not using a specified @var{src_port} a random port is automatically chosen. 3081 3082If you just want a simple readonly console you can use @code{netcat} or 3083@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3084@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3085will appear in the netconsole session. 3086 3087If you plan to send characters back via netconsole or you want to stop 3088and start QEMU a lot of times, you should have QEMU use the same 3089source port each time by using something like @code{-serial 3090udp::4555@@:4556} to QEMU. Another approach is to use a patched 3091version of netcat which can listen to a TCP port and send and receive 3092characters via udp. If you have a patched version of netcat which 3093activates telnet remote echo and single char transfer, then you can 3094use the following options to set up a netcat redirector to allow 3095telnet on port 5555 to access the QEMU port. 3096@table @code 3097@item QEMU Options: 3098-serial udp::4555@@:4556 3099@item netcat options: 3100-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3101@item telnet options: 3102localhost 5555 3103@end table 3104 3105@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3106The TCP Net Console has two modes of operation. It can send the serial 3107I/O to a location or wait for a connection from a location. By default 3108the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3109the @var{server} option QEMU will wait for a client socket application 3110to connect to the port before continuing, unless the @code{nowait} 3111option was specified. The @code{nodelay} option disables the Nagle buffering 3112algorithm. The @code{reconnect} option only applies if @var{noserver} is 3113set, if the connection goes down it will attempt to reconnect at the 3114given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3115one TCP connection at a time is accepted. You can use @code{telnet} to 3116connect to the corresponding character device. 3117@table @code 3118@item Example to send tcp console to 192.168.0.2 port 4444 3119-serial tcp:192.168.0.2:4444 3120@item Example to listen and wait on port 4444 for connection 3121-serial tcp::4444,server 3122@item Example to not wait and listen on ip 192.168.0.100 port 4444 3123-serial tcp:192.168.0.100:4444,server,nowait 3124@end table 3125 3126@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3127The telnet protocol is used instead of raw tcp sockets. The options 3128work the same as if you had specified @code{-serial tcp}. The 3129difference is that the port acts like a telnet server or client using 3130telnet option negotiation. This will also allow you to send the 3131MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3132sequence. Typically in unix telnet you do it with Control-] and then 3133type "send break" followed by pressing the enter key. 3134 3135@item websocket:@var{host}:@var{port},server[,nowait][,nodelay] 3136The WebSocket protocol is used instead of raw tcp socket. The port acts as 3137a WebSocket server. Client mode is not supported. 3138 3139@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3140A unix domain socket is used instead of a tcp socket. The option works the 3141same as if you had specified @code{-serial tcp} except the unix domain socket 3142@var{path} is used for connections. 3143 3144@item mon:@var{dev_string} 3145This is a special option to allow the monitor to be multiplexed onto 3146another serial port. The monitor is accessed with key sequence of 3147@key{Control-a} and then pressing @key{c}. 3148@var{dev_string} should be any one of the serial devices specified 3149above. An example to multiplex the monitor onto a telnet server 3150listening on port 4444 would be: 3151@table @code 3152@item -serial mon:telnet::4444,server,nowait 3153@end table 3154When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3155QEMU any more but will be passed to the guest instead. 3156 3157@item braille 3158Braille device. This will use BrlAPI to display the braille output on a real 3159or fake device. 3160 3161@item msmouse 3162Three button serial mouse. Configure the guest to use Microsoft protocol. 3163@end table 3164ETEXI 3165 3166DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3167 "-parallel dev redirect the parallel port to char device 'dev'\n", 3168 QEMU_ARCH_ALL) 3169STEXI 3170@item -parallel @var{dev} 3171@findex -parallel 3172Redirect the virtual parallel port to host device @var{dev} (same 3173devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3174be used to use hardware devices connected on the corresponding host 3175parallel port. 3176 3177This option can be used several times to simulate up to 3 parallel 3178ports. 3179 3180Use @code{-parallel none} to disable all parallel ports. 3181ETEXI 3182 3183DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3184 "-monitor dev redirect the monitor to char device 'dev'\n", 3185 QEMU_ARCH_ALL) 3186STEXI 3187@item -monitor @var{dev} 3188@findex -monitor 3189Redirect the monitor to host device @var{dev} (same devices as the 3190serial port). 3191The default device is @code{vc} in graphical mode and @code{stdio} in 3192non graphical mode. 3193Use @code{-monitor none} to disable the default monitor. 3194ETEXI 3195DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3196 "-qmp dev like -monitor but opens in 'control' mode\n", 3197 QEMU_ARCH_ALL) 3198STEXI 3199@item -qmp @var{dev} 3200@findex -qmp 3201Like -monitor but opens in 'control' mode. 3202ETEXI 3203DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3204 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3205 QEMU_ARCH_ALL) 3206STEXI 3207@item -qmp-pretty @var{dev} 3208@findex -qmp-pretty 3209Like -qmp but uses pretty JSON formatting. 3210ETEXI 3211 3212DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3213 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL) 3214STEXI 3215@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]] 3216@findex -mon 3217Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing 3218easing human reading and debugging. 3219ETEXI 3220 3221DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3222 "-debugcon dev redirect the debug console to char device 'dev'\n", 3223 QEMU_ARCH_ALL) 3224STEXI 3225@item -debugcon @var{dev} 3226@findex -debugcon 3227Redirect the debug console to host device @var{dev} (same devices as the 3228serial port). The debug console is an I/O port which is typically port 32290xe9; writing to that I/O port sends output to this device. 3230The default device is @code{vc} in graphical mode and @code{stdio} in 3231non graphical mode. 3232ETEXI 3233 3234DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3235 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3236STEXI 3237@item -pidfile @var{file} 3238@findex -pidfile 3239Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3240from a script. 3241ETEXI 3242 3243DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3244 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3245STEXI 3246@item -singlestep 3247@findex -singlestep 3248Run the emulation in single step mode. 3249ETEXI 3250 3251DEF("preconfig", 0, QEMU_OPTION_preconfig, \ 3252 "--preconfig pause QEMU before machine is initialized (experimental)\n", 3253 QEMU_ARCH_ALL) 3254STEXI 3255@item --preconfig 3256@findex --preconfig 3257Pause QEMU for interactive configuration before the machine is created, 3258which allows querying and configuring properties that will affect 3259machine initialization. Use QMP command 'x-exit-preconfig' to exit 3260the preconfig state and move to the next state (i.e. run guest if -S 3261isn't used or pause the second time if -S is used). This option is 3262experimental. 3263ETEXI 3264 3265DEF("S", 0, QEMU_OPTION_S, \ 3266 "-S freeze CPU at startup (use 'c' to start execution)\n", 3267 QEMU_ARCH_ALL) 3268STEXI 3269@item -S 3270@findex -S 3271Do not start CPU at startup (you must type 'c' in the monitor). 3272ETEXI 3273 3274DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3275 "-realtime [mlock=on|off]\n" 3276 " run qemu with realtime features\n" 3277 " mlock=on|off controls mlock support (default: on)\n", 3278 QEMU_ARCH_ALL) 3279STEXI 3280@item -realtime mlock=on|off 3281@findex -realtime 3282Run qemu with realtime features. 3283mlocking qemu and guest memory can be enabled via @option{mlock=on} 3284(enabled by default). 3285ETEXI 3286 3287DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, 3288 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" 3289 " run qemu with overcommit hints\n" 3290 " mem-lock=on|off controls memory lock support (default: off)\n" 3291 " cpu-pm=on|off controls cpu power management (default: off)\n", 3292 QEMU_ARCH_ALL) 3293STEXI 3294@item -overcommit mem-lock=on|off 3295@item -overcommit cpu-pm=on|off 3296@findex -overcommit 3297Run qemu with hints about host resource overcommit. The default is 3298to assume that host overcommits all resources. 3299 3300Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled 3301by default). This works when host memory is not overcommitted and reduces the 3302worst-case latency for guest. This is equivalent to @option{realtime}. 3303 3304Guest ability to manage power state of host cpus (increasing latency for other 3305processes on the same host cpu, but decreasing latency for guest) can be 3306enabled via @option{cpu-pm=on} (disabled by default). This works best when 3307host CPU is not overcommitted. When used, host estimates of CPU cycle and power 3308utilization will be incorrect, not taking into account guest idle time. 3309ETEXI 3310 3311DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3312 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3313STEXI 3314@item -gdb @var{dev} 3315@findex -gdb 3316Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3317connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3318stdio are reasonable use case. The latter is allowing to start QEMU from 3319within gdb and establish the connection via a pipe: 3320@example 3321(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3322@end example 3323ETEXI 3324 3325DEF("s", 0, QEMU_OPTION_s, \ 3326 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3327 QEMU_ARCH_ALL) 3328STEXI 3329@item -s 3330@findex -s 3331Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3332(@pxref{gdb_usage}). 3333ETEXI 3334 3335DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3336 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3337 QEMU_ARCH_ALL) 3338STEXI 3339@item -d @var{item1}[,...] 3340@findex -d 3341Enable logging of specified items. Use '-d help' for a list of log items. 3342ETEXI 3343 3344DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3345 "-D logfile output log to logfile (default stderr)\n", 3346 QEMU_ARCH_ALL) 3347STEXI 3348@item -D @var{logfile} 3349@findex -D 3350Output log in @var{logfile} instead of to stderr 3351ETEXI 3352 3353DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3354 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3355 QEMU_ARCH_ALL) 3356STEXI 3357@item -dfilter @var{range1}[,...] 3358@findex -dfilter 3359Filter debug output to that relevant to a range of target addresses. The filter 3360spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3361@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3362addresses and sizes required. For example: 3363@example 3364 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3365@end example 3366Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3367the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3368block starting at 0xffffffc00005f000. 3369ETEXI 3370 3371DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3372 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3373 QEMU_ARCH_ALL) 3374STEXI 3375@item -L @var{path} 3376@findex -L 3377Set the directory for the BIOS, VGA BIOS and keymaps. 3378 3379To list all the data directories, use @code{-L help}. 3380ETEXI 3381 3382DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3383 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3384STEXI 3385@item -bios @var{file} 3386@findex -bios 3387Set the filename for the BIOS. 3388ETEXI 3389 3390DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3391 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3392STEXI 3393@item -enable-kvm 3394@findex -enable-kvm 3395Enable KVM full virtualization support. This option is only available 3396if KVM support is enabled when compiling. 3397ETEXI 3398 3399DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3400 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3401DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3402 "-xen-attach attach to existing xen domain\n" 3403 " libxl will use this when starting QEMU\n", 3404 QEMU_ARCH_ALL) 3405DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict, 3406 "-xen-domid-restrict restrict set of available xen operations\n" 3407 " to specified domain id. (Does not affect\n" 3408 " xenpv machine type).\n", 3409 QEMU_ARCH_ALL) 3410STEXI 3411@item -xen-domid @var{id} 3412@findex -xen-domid 3413Specify xen guest domain @var{id} (XEN only). 3414@item -xen-attach 3415@findex -xen-attach 3416Attach to existing xen domain. 3417libxl will use this when starting QEMU (XEN only). 3418@findex -xen-domid-restrict 3419Restrict set of available xen operations to specified domain id (XEN only). 3420ETEXI 3421 3422DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3423 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3424STEXI 3425@item -no-reboot 3426@findex -no-reboot 3427Exit instead of rebooting. 3428ETEXI 3429 3430DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3431 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3432STEXI 3433@item -no-shutdown 3434@findex -no-shutdown 3435Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3436This allows for instance switching to monitor to commit changes to the 3437disk image. 3438ETEXI 3439 3440DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3441 "-loadvm [tag|id]\n" \ 3442 " start right away with a saved state (loadvm in monitor)\n", 3443 QEMU_ARCH_ALL) 3444STEXI 3445@item -loadvm @var{file} 3446@findex -loadvm 3447Start right away with a saved state (@code{loadvm} in monitor) 3448ETEXI 3449 3450#ifndef _WIN32 3451DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3452 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3453#endif 3454STEXI 3455@item -daemonize 3456@findex -daemonize 3457Daemonize the QEMU process after initialization. QEMU will not detach from 3458standard IO until it is ready to receive connections on any of its devices. 3459This option is a useful way for external programs to launch QEMU without having 3460to cope with initialization race conditions. 3461ETEXI 3462 3463DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3464 "-option-rom rom load a file, rom, into the option ROM space\n", 3465 QEMU_ARCH_ALL) 3466STEXI 3467@item -option-rom @var{file} 3468@findex -option-rom 3469Load the contents of @var{file} as an option ROM. 3470This option is useful to load things like EtherBoot. 3471ETEXI 3472 3473DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3474 "-rtc [base=utc|localtime|<datetime>][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3475 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3476 QEMU_ARCH_ALL) 3477 3478STEXI 3479 3480@item -rtc [base=utc|localtime|@var{datetime}][,clock=host|rt|vm][,driftfix=none|slew] 3481@findex -rtc 3482Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3483UTC or local time, respectively. @code{localtime} is required for correct date in 3484MS-DOS or Windows. To start at a specific point in time, provide @var{datetime} in the 3485format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3486 3487By default the RTC is driven by the host system time. This allows using of the 3488RTC as accurate reference clock inside the guest, specifically if the host 3489time is smoothly following an accurate external reference clock, e.g. via NTP. 3490If you want to isolate the guest time from the host, you can set @option{clock} 3491to @code{rt} instead, which provides a host monotonic clock if host support it. 3492To even prevent the RTC from progressing during suspension, you can set @option{clock} 3493to @code{vm} (virtual clock). @samp{clock=vm} is recommended especially in 3494icount mode in order to preserve determinism; however, note that in icount mode 3495the speed of the virtual clock is variable and can in general differ from the 3496host clock. 3497 3498Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3499specifically with Windows' ACPI HAL. This option will try to figure out how 3500many timer interrupts were not processed by the Windows guest and will 3501re-inject them. 3502ETEXI 3503 3504DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3505 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3506 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3507 " instruction, enable aligning the host and virtual clocks\n" \ 3508 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3509STEXI 3510@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3511@findex -icount 3512Enable virtual instruction counter. The virtual cpu will execute one 3513instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3514then the virtual cpu speed will be automatically adjusted to keep virtual 3515time within a few seconds of real time. 3516 3517When the virtual cpu is sleeping, the virtual time will advance at default 3518speed unless @option{sleep=on|off} is specified. 3519With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3520instantly whenever the virtual cpu goes to sleep mode and will not advance 3521if no timer is enabled. This behavior give deterministic execution times from 3522the guest point of view. 3523 3524Note that while this option can give deterministic behavior, it does not 3525provide cycle accurate emulation. Modern CPUs contain superscalar out of 3526order cores with complex cache hierarchies. The number of instructions 3527executed often has little or no correlation with actual performance. 3528 3529@option{align=on} will activate the delay algorithm which will try 3530to synchronise the host clock and the virtual clock. The goal is to 3531have a guest running at the real frequency imposed by the shift option. 3532Whenever the guest clock is behind the host clock and if 3533@option{align=on} is specified then we print a message to the user 3534to inform about the delay. 3535Currently this option does not work when @option{shift} is @code{auto}. 3536Note: The sync algorithm will work for those shift values for which 3537the guest clock runs ahead of the host clock. Typically this happens 3538when the shift value is high (how high depends on the host machine). 3539 3540When @option{rr} option is specified deterministic record/replay is enabled. 3541Replay log is written into @var{filename} file in record mode and 3542read from this file in replay mode. 3543 3544Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3545at the start of execution recording. In replay mode this option is used 3546to load the initial VM state. 3547ETEXI 3548 3549DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3550 "-watchdog model\n" \ 3551 " enable virtual hardware watchdog [default=none]\n", 3552 QEMU_ARCH_ALL) 3553STEXI 3554@item -watchdog @var{model} 3555@findex -watchdog 3556Create a virtual hardware watchdog device. Once enabled (by a guest 3557action), the watchdog must be periodically polled by an agent inside 3558the guest or else the guest will be restarted. Choose a model for 3559which your guest has drivers. 3560 3561The @var{model} is the model of hardware watchdog to emulate. Use 3562@code{-watchdog help} to list available hardware models. Only one 3563watchdog can be enabled for a guest. 3564 3565The following models may be available: 3566@table @option 3567@item ib700 3568iBASE 700 is a very simple ISA watchdog with a single timer. 3569@item i6300esb 3570Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3571dual-timer watchdog. 3572@item diag288 3573A virtual watchdog for s390x backed by the diagnose 288 hypercall 3574(currently KVM only). 3575@end table 3576ETEXI 3577 3578DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3579 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \ 3580 " action when watchdog fires [default=reset]\n", 3581 QEMU_ARCH_ALL) 3582STEXI 3583@item -watchdog-action @var{action} 3584@findex -watchdog-action 3585 3586The @var{action} controls what QEMU will do when the watchdog timer 3587expires. 3588The default is 3589@code{reset} (forcefully reset the guest). 3590Other possible actions are: 3591@code{shutdown} (attempt to gracefully shutdown the guest), 3592@code{poweroff} (forcefully poweroff the guest), 3593@code{inject-nmi} (inject a NMI into the guest), 3594@code{pause} (pause the guest), 3595@code{debug} (print a debug message and continue), or 3596@code{none} (do nothing). 3597 3598Note that the @code{shutdown} action requires that the guest responds 3599to ACPI signals, which it may not be able to do in the sort of 3600situations where the watchdog would have expired, and thus 3601@code{-watchdog-action shutdown} is not recommended for production use. 3602 3603Examples: 3604 3605@table @code 3606@item -watchdog i6300esb -watchdog-action pause 3607@itemx -watchdog ib700 3608@end table 3609ETEXI 3610 3611DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3612 "-echr chr set terminal escape character instead of ctrl-a\n", 3613 QEMU_ARCH_ALL) 3614STEXI 3615 3616@item -echr @var{numeric_ascii_value} 3617@findex -echr 3618Change the escape character used for switching to the monitor when using 3619monitor and serial sharing. The default is @code{0x01} when using the 3620@code{-nographic} option. @code{0x01} is equal to pressing 3621@code{Control-a}. You can select a different character from the ascii 3622control keys where 1 through 26 map to Control-a through Control-z. For 3623instance you could use the either of the following to change the escape 3624character to Control-t. 3625@table @code 3626@item -echr 0x14 3627@itemx -echr 20 3628@end table 3629ETEXI 3630 3631DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3632 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3633STEXI 3634@item -show-cursor 3635@findex -show-cursor 3636Show cursor. 3637ETEXI 3638 3639DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3640 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3641STEXI 3642@item -tb-size @var{n} 3643@findex -tb-size 3644Set TB size. 3645ETEXI 3646 3647DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3648 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3649 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3650 "-incoming unix:socketpath\n" \ 3651 " prepare for incoming migration, listen on\n" \ 3652 " specified protocol and socket address\n" \ 3653 "-incoming fd:fd\n" \ 3654 "-incoming exec:cmdline\n" \ 3655 " accept incoming migration on given file descriptor\n" \ 3656 " or from given external command\n" \ 3657 "-incoming defer\n" \ 3658 " wait for the URI to be specified via migrate_incoming\n", 3659 QEMU_ARCH_ALL) 3660STEXI 3661@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3662@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3663@findex -incoming 3664Prepare for incoming migration, listen on a given tcp port. 3665 3666@item -incoming unix:@var{socketpath} 3667Prepare for incoming migration, listen on a given unix socket. 3668 3669@item -incoming fd:@var{fd} 3670Accept incoming migration from a given filedescriptor. 3671 3672@item -incoming exec:@var{cmdline} 3673Accept incoming migration as an output from specified external command. 3674 3675@item -incoming defer 3676Wait for the URI to be specified via migrate_incoming. The monitor can 3677be used to change settings (such as migration parameters) prior to issuing 3678the migrate_incoming to allow the migration to begin. 3679ETEXI 3680 3681DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3682 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3683STEXI 3684@item -only-migratable 3685@findex -only-migratable 3686Only allow migratable devices. Devices will not be allowed to enter an 3687unmigratable state. 3688ETEXI 3689 3690DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3691 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3692STEXI 3693@item -nodefaults 3694@findex -nodefaults 3695Don't create default devices. Normally, QEMU sets the default devices like serial 3696port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3697CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3698default devices. 3699ETEXI 3700 3701#ifndef _WIN32 3702DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3703 "-chroot dir chroot to dir just before starting the VM\n", 3704 QEMU_ARCH_ALL) 3705#endif 3706STEXI 3707@item -chroot @var{dir} 3708@findex -chroot 3709Immediately before starting guest execution, chroot to the specified 3710directory. Especially useful in combination with -runas. 3711ETEXI 3712 3713#ifndef _WIN32 3714DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3715 "-runas user change to user id user just before starting the VM\n" \ 3716 " user can be numeric uid:gid instead\n", 3717 QEMU_ARCH_ALL) 3718#endif 3719STEXI 3720@item -runas @var{user} 3721@findex -runas 3722Immediately before starting guest execution, drop root privileges, switching 3723to the specified user. 3724ETEXI 3725 3726DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3727 "-prom-env variable=value\n" 3728 " set OpenBIOS nvram variables\n", 3729 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3730STEXI 3731@item -prom-env @var{variable}=@var{value} 3732@findex -prom-env 3733Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3734ETEXI 3735DEF("semihosting", 0, QEMU_OPTION_semihosting, 3736 "-semihosting semihosting mode\n", 3737 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3738 QEMU_ARCH_MIPS) 3739STEXI 3740@item -semihosting 3741@findex -semihosting 3742Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3743ETEXI 3744DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3745 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3746 " semihosting configuration\n", 3747QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3748QEMU_ARCH_MIPS) 3749STEXI 3750@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3751@findex -semihosting-config 3752Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3753@table @option 3754@item target=@code{native|gdb|auto} 3755Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3756or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3757during debug sessions and @code{native} otherwise. 3758@item arg=@var{str1},arg=@var{str2},... 3759Allows the user to pass input arguments, and can be used multiple times to build 3760up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3761command line is still supported for backward compatibility. If both the 3762@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3763specified, the former is passed to semihosting as it always takes precedence. 3764@end table 3765ETEXI 3766DEF("old-param", 0, QEMU_OPTION_old_param, 3767 "-old-param old param mode\n", QEMU_ARCH_ARM) 3768STEXI 3769@item -old-param 3770@findex -old-param (ARM) 3771Old param mode (ARM only). 3772ETEXI 3773 3774DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3775 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \ 3776 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \ 3777 " Enable seccomp mode 2 system call filter (default 'off').\n" \ 3778 " use 'obsolete' to allow obsolete system calls that are provided\n" \ 3779 " by the kernel, but typically no longer used by modern\n" \ 3780 " C library implementations.\n" \ 3781 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \ 3782 " its privileges by blacklisting all set*uid|gid system calls.\n" \ 3783 " The value 'children' will deny set*uid|gid system calls for\n" \ 3784 " main QEMU process but will allow forks and execves to run unprivileged\n" \ 3785 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \ 3786 " blacklisting *fork and execve\n" \ 3787 " use 'resourcecontrol' to disable process affinity and schedular priority\n", 3788 QEMU_ARCH_ALL) 3789STEXI 3790@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}] 3791@findex -sandbox 3792Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3793disable it. The default is 'off'. 3794@table @option 3795@item obsolete=@var{string} 3796Enable Obsolete system calls 3797@item elevateprivileges=@var{string} 3798Disable set*uid|gid system calls 3799@item spawn=@var{string} 3800Disable *fork and execve 3801@item resourcecontrol=@var{string} 3802Disable process affinity and schedular priority 3803@end table 3804ETEXI 3805 3806DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3807 "-readconfig <file>\n", QEMU_ARCH_ALL) 3808STEXI 3809@item -readconfig @var{file} 3810@findex -readconfig 3811Read device configuration from @var{file}. This approach is useful when you want to spawn 3812QEMU process with many command line options but you don't want to exceed the command line 3813character limit. 3814ETEXI 3815DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3816 "-writeconfig <file>\n" 3817 " read/write config file\n", QEMU_ARCH_ALL) 3818STEXI 3819@item -writeconfig @var{file} 3820@findex -writeconfig 3821Write device configuration to @var{file}. The @var{file} can be either filename to save 3822command line and device configuration into file or dash @code{-}) character to print the 3823output to stdout. This can be later used as input file for @code{-readconfig} option. 3824ETEXI 3825 3826DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3827 "-no-user-config\n" 3828 " do not load default user-provided config files at startup\n", 3829 QEMU_ARCH_ALL) 3830STEXI 3831@item -no-user-config 3832@findex -no-user-config 3833The @code{-no-user-config} option makes QEMU not load any of the user-provided 3834config files on @var{sysconfdir}. 3835ETEXI 3836 3837DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3838 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3839 " specify tracing options\n", 3840 QEMU_ARCH_ALL) 3841STEXI 3842HXCOMM This line is not accurate, as some sub-options are backend-specific but 3843HXCOMM HX does not support conditional compilation of text. 3844@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 3845@findex -trace 3846@include qemu-option-trace.texi 3847ETEXI 3848 3849HXCOMM Internal use 3850DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3851DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3852 3853#ifdef __linux__ 3854DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3855 "-enable-fips enable FIPS 140-2 compliance\n", 3856 QEMU_ARCH_ALL) 3857#endif 3858STEXI 3859@item -enable-fips 3860@findex -enable-fips 3861Enable FIPS 140-2 compliance mode. 3862ETEXI 3863 3864HXCOMM Deprecated by -machine accel=tcg property 3865DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3866 3867DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3868 "-msg timestamp[=on|off]\n" 3869 " change the format of messages\n" 3870 " on|off controls leading timestamps (default:on)\n", 3871 QEMU_ARCH_ALL) 3872STEXI 3873@item -msg timestamp[=on|off] 3874@findex -msg 3875prepend a timestamp to each log message.(default:on) 3876ETEXI 3877 3878DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3879 "-dump-vmstate <file>\n" 3880 " Output vmstate information in JSON format to file.\n" 3881 " Use the scripts/vmstate-static-checker.py file to\n" 3882 " check for possible regressions in migration code\n" 3883 " by comparing two such vmstate dumps.\n", 3884 QEMU_ARCH_ALL) 3885STEXI 3886@item -dump-vmstate @var{file} 3887@findex -dump-vmstate 3888Dump json-encoded vmstate information for current machine type to file 3889in @var{file} 3890ETEXI 3891 3892DEF("enable-sync-profile", 0, QEMU_OPTION_enable_sync_profile, 3893 "-enable-sync-profile\n" 3894 " enable synchronization profiling\n", 3895 QEMU_ARCH_ALL) 3896STEXI 3897@item -enable-sync-profile 3898@findex -enable-sync-profile 3899Enable synchronization profiling. 3900ETEXI 3901 3902STEXI 3903@end table 3904ETEXI 3905DEFHEADING() 3906 3907DEFHEADING(Generic object creation:) 3908STEXI 3909@table @option 3910ETEXI 3911 3912DEF("object", HAS_ARG, QEMU_OPTION_object, 3913 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3914 " create a new object of type TYPENAME setting properties\n" 3915 " in the order they are specified. Note that the 'id'\n" 3916 " property must be set. These objects are placed in the\n" 3917 " '/objects' path.\n", 3918 QEMU_ARCH_ALL) 3919STEXI 3920@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3921@findex -object 3922Create a new object of type @var{typename} setting properties 3923in the order they are specified. Note that the 'id' 3924property must be set. These objects are placed in the 3925'/objects' path. 3926 3927@table @option 3928 3929@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} 3930 3931Creates a memory file backend object, which can be used to back 3932the guest RAM with huge pages. 3933 3934The @option{id} parameter is a unique ID that will be used to reference this 3935memory region when configuring the @option{-numa} argument. 3936 3937The @option{size} option provides the size of the memory region, and accepts 3938common suffixes, eg @option{500M}. 3939 3940The @option{mem-path} provides the path to either a shared memory or huge page 3941filesystem mount. 3942 3943The @option{share} boolean option determines whether the memory 3944region is marked as private to QEMU, or shared. The latter allows 3945a co-operating external process to access the QEMU memory region. 3946 3947The @option{share} is also required for pvrdma devices due to 3948limitations in the RDMA API provided by Linux. 3949 3950Setting share=on might affect the ability to configure NUMA 3951bindings for the memory backend under some circumstances, see 3952Documentation/vm/numa_memory_policy.txt on the Linux kernel 3953source tree for additional details. 3954 3955Setting the @option{discard-data} boolean option to @var{on} 3956indicates that file contents can be destroyed when QEMU exits, 3957to avoid unnecessarily flushing data to the backing file. Note 3958that @option{discard-data} is only an optimization, and QEMU 3959might not discard file contents if it aborts unexpectedly or is 3960terminated using SIGKILL. 3961 3962The @option{merge} boolean option enables memory merge, also known as 3963MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for 3964memory deduplication. 3965 3966Setting the @option{dump} boolean option to @var{off} excludes the memory from 3967core dumps. This feature is also known as MADV_DONTDUMP. 3968 3969The @option{prealloc} boolean option enables memory preallocation. 3970 3971The @option{host-nodes} option binds the memory range to a list of NUMA host 3972nodes. 3973 3974The @option{policy} option sets the NUMA policy to one of the following values: 3975 3976@table @option 3977@item @var{default} 3978default host policy 3979 3980@item @var{preferred} 3981prefer the given host node list for allocation 3982 3983@item @var{bind} 3984restrict memory allocation to the given host node list 3985 3986@item @var{interleave} 3987interleave memory allocations across the given host node list 3988@end table 3989 3990The @option{align} option specifies the base address alignment when 3991QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg 3992@option{2M}. Some backend store specified by @option{mem-path} 3993requires an alignment different than the default one used by QEMU, eg 3994the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In 3995such cases, users can specify the required alignment via this option. 3996 3997The @option{pmem} option specifies whether the backing file specified 3998by @option{mem-path} is in host persistent memory that can be accessed 3999using the SNIA NVM programming model (e.g. Intel NVDIMM). 4000If @option{pmem} is set to 'on', QEMU will take necessary operations to 4001guarantee the persistence of its own writes to @option{mem-path} 4002(e.g. in vNVDIMM label emulation and live migration). 4003 4004@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} 4005 4006Creates a memory backend object, which can be used to back the guest RAM. 4007Memory backend objects offer more control than the @option{-m} option that is 4008traditionally used to define guest RAM. Please refer to 4009@option{memory-backend-file} for a description of the options. 4010 4011@item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},share=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size} 4012 4013Creates an anonymous memory file backend object, which allows QEMU to 4014share the memory with an external process (e.g. when using 4015vhost-user). The memory is allocated with memfd and optional 4016sealing. (Linux only) 4017 4018The @option{seal} option creates a sealed-file, that will block 4019further resizing the memory ('on' by default). 4020 4021The @option{hugetlb} option specify the file to be created resides in 4022the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with 4023the @option{hugetlb} option, the @option{hugetlbsize} option specify 4024the hugetlb page size on systems that support multiple hugetlb page 4025sizes (it must be a power of 2 value supported by the system). 4026 4027In some versions of Linux, the @option{hugetlb} option is incompatible 4028with the @option{seal} option (requires at least Linux 4.16). 4029 4030Please refer to @option{memory-backend-file} for a description of the 4031other options. 4032 4033The @option{share} boolean option is @var{on} by default with memfd. 4034 4035@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4036 4037Creates a random number generator backend which obtains entropy from 4038a device on the host. The @option{id} parameter is a unique ID that 4039will be used to reference this entropy backend from the @option{virtio-rng} 4040device. The @option{filename} parameter specifies which file to obtain 4041entropy from and if omitted defaults to @option{/dev/random}. 4042 4043@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4044 4045Creates a random number generator backend which obtains entropy from 4046an external daemon running on the host. The @option{id} parameter is 4047a unique ID that will be used to reference this entropy backend from 4048the @option{virtio-rng} device. The @option{chardev} parameter is 4049the unique ID of a character device backend that provides the connection 4050to the RNG daemon. 4051 4052@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4053 4054Creates a TLS anonymous credentials object, which can be used to provide 4055TLS support on network backends. The @option{id} parameter is a unique 4056ID which network backends will use to access the credentials. The 4057@option{endpoint} is either @option{server} or @option{client} depending 4058on whether the QEMU network backend that uses the credentials will be 4059acting as a client or as a server. If @option{verify-peer} is enabled 4060(the default) then once the handshake is completed, the peer credentials 4061will be verified, though this is a no-op for anonymous credentials. 4062 4063The @var{dir} parameter tells QEMU where to find the credential 4064files. For server endpoints, this directory may contain a file 4065@var{dh-params.pem} providing diffie-hellman parameters to use 4066for the TLS server. If the file is missing, QEMU will generate 4067a set of DH parameters at startup. This is a computationally 4068expensive operation that consumes random pool entropy, so it is 4069recommended that a persistent set of parameters be generated 4070upfront and saved. 4071 4072@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] 4073 4074Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide 4075TLS support on network backends. The @option{id} parameter is a unique 4076ID which network backends will use to access the credentials. The 4077@option{endpoint} is either @option{server} or @option{client} depending 4078on whether the QEMU network backend that uses the credentials will be 4079acting as a client or as a server. For clients only, @option{username} 4080is the username which will be sent to the server. If omitted 4081it defaults to ``qemu''. 4082 4083The @var{dir} parameter tells QEMU where to find the keys file. 4084It is called ``@var{dir}/keys.psk'' and contains ``username:key'' 4085pairs. This file can most easily be created using the GnuTLS 4086@code{psktool} program. 4087 4088For server endpoints, @var{dir} may also contain a file 4089@var{dh-params.pem} providing diffie-hellman parameters to use 4090for the TLS server. If the file is missing, QEMU will generate 4091a set of DH parameters at startup. This is a computationally 4092expensive operation that consumes random pool entropy, so it is 4093recommended that a persistent set of parameters be generated 4094up front and saved. 4095 4096@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} 4097 4098Creates a TLS anonymous credentials object, which can be used to provide 4099TLS support on network backends. The @option{id} parameter is a unique 4100ID which network backends will use to access the credentials. The 4101@option{endpoint} is either @option{server} or @option{client} depending 4102on whether the QEMU network backend that uses the credentials will be 4103acting as a client or as a server. If @option{verify-peer} is enabled 4104(the default) then once the handshake is completed, the peer credentials 4105will be verified. With x509 certificates, this implies that the clients 4106must be provided with valid client certificates too. 4107 4108The @var{dir} parameter tells QEMU where to find the credential 4109files. For server endpoints, this directory may contain a file 4110@var{dh-params.pem} providing diffie-hellman parameters to use 4111for the TLS server. If the file is missing, QEMU will generate 4112a set of DH parameters at startup. This is a computationally 4113expensive operation that consumes random pool entropy, so it is 4114recommended that a persistent set of parameters be generated 4115upfront and saved. 4116 4117For x509 certificate credentials the directory will contain further files 4118providing the x509 certificates. The certificates must be stored 4119in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4120@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4121@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4122 4123For the @var{server-key.pem} and @var{client-key.pem} files which 4124contain sensitive private keys, it is possible to use an encrypted 4125version by providing the @var{passwordid} parameter. This provides 4126the ID of a previously created @code{secret} object containing the 4127password for decryption. 4128 4129The @var{priority} parameter allows to override the global default 4130priority used by gnutls. This can be useful if the system administrator 4131needs to use a weaker set of crypto priorities for QEMU without 4132potentially forcing the weakness onto all applications. Or conversely 4133if one wants wants a stronger default for QEMU than for all other 4134applications, they can do this through this parameter. Its format is 4135a gnutls priority string as described at 4136@url{https://gnutls.org/manual/html_node/Priority-Strings.html}. 4137 4138@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4139 4140Interval @var{t} can't be 0, this filter batches the packet delivery: all 4141packets arriving in a given interval on netdev @var{netdevid} are delayed 4142until the end of the interval. Interval is in microseconds. 4143@option{status} is optional that indicate whether the netfilter is 4144on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4145 4146queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4147 4148@option{all}: the filter is attached both to the receive and the transmit 4149 queue of the netdev (default). 4150 4151@option{rx}: the filter is attached to the receive queue of the netdev, 4152 where it will receive packets sent to the netdev. 4153 4154@option{tx}: the filter is attached to the transmit queue of the netdev, 4155 where it will receive packets sent by the netdev. 4156 4157@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4158 4159filter-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. 4160 4161@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4162 4163filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4164@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag, 4165filter-redirector will redirect packet with vnet_hdr_len. 4166Create a filter-redirector we need to differ outdev id from indev id, id can not 4167be the same. we can just use indev or outdev, but at least one of indev or outdev 4168need to be specified. 4169 4170@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support] 4171 4172Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4173secondary from primary to keep secondary tcp connection,and rewrite 4174tcp packet to primary from secondary make tcp packet can be handled by 4175client.if it has the vnet_hdr_support flag, we can parse packet with vnet header. 4176 4177usage: 4178colo secondary: 4179-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4180-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4181-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4182 4183@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4184 4185Dump the network traffic on netdev @var{dev} to the file specified by 4186@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4187The file format is libpcap, so it can be analyzed with tools such as tcpdump 4188or Wireshark. 4189 4190@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support] 4191 4192Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4193secondary packet. If the packets are same, we will output primary 4194packet to outdev@var{chardevid}, else we will notify colo-frame 4195do checkpoint and send primary packet to outdev@var{chardevid}. 4196if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len. 4197 4198we must use it with the help of filter-mirror and filter-redirector. 4199 4200@example 4201 4202primary: 4203-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4204-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4205-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4206-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4207-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4208-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4209-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4210-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4211-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4212-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4213-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4214-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4215 4216secondary: 4217-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4218-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4219-chardev socket,id=red0,host=3.3.3.3,port=9003 4220-chardev socket,id=red1,host=3.3.3.3,port=9004 4221-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4222-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4223 4224@end example 4225 4226If you want to know the detail of above command line, you can read 4227the colo-compare git log. 4228 4229@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4230 4231Creates a cryptodev backend which executes crypto opreation from 4232the QEMU cipher APIS. The @var{id} parameter is 4233a unique ID that will be used to reference this cryptodev backend from 4234the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4235which specify the queue number of cryptodev backend, the default of 4236@var{queues} is 1. 4237 4238@example 4239 4240 # qemu-system-x86_64 \ 4241 [...] \ 4242 -object cryptodev-backend-builtin,id=cryptodev0 \ 4243 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4244 [...] 4245@end example 4246 4247@item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}] 4248 4249Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}. 4250The @var{id} parameter is a unique ID that will be used to reference this 4251cryptodev backend from the @option{virtio-crypto} device. 4252The chardev should be a unix domain socket backed one. The vhost-user uses 4253a specifically defined protocol to pass vhost ioctl replacement messages 4254to an application on the other end of the socket. 4255The @var{queues} parameter is optional, which specify the queue number 4256of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1. 4257 4258@example 4259 4260 # qemu-system-x86_64 \ 4261 [...] \ 4262 -chardev socket,id=chardev0,path=/path/to/socket \ 4263 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \ 4264 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4265 [...] 4266@end example 4267 4268@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4269@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4270 4271Defines a secret to store a password, encryption key, or some other sensitive 4272data. The sensitive data can either be passed directly via the @var{data} 4273parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4274parameter is insecure unless the sensitive data is encrypted. 4275 4276The sensitive data can be provided in raw format (the default), or base64. 4277When encoded as JSON, the raw format only supports valid UTF-8 characters, 4278so base64 is recommended for sending binary data. QEMU will convert from 4279which ever format is provided to the format it needs internally. eg, an 4280RBD password can be provided in raw format, even though it will be base64 4281encoded when passed onto the RBD sever. 4282 4283For added protection, it is possible to encrypt the data associated with 4284a secret using the AES-256-CBC cipher. Use of encryption is indicated 4285by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4286parameter provides the ID of a previously defined secret that contains 4287the AES-256 decryption key. This key should be 32-bytes long and be 4288base64 encoded. The @var{iv} parameter provides the random initialization 4289vector used for encryption of this particular secret and should be a 4290base64 encrypted string of the 16-byte IV. 4291 4292The simplest (insecure) usage is to provide the secret inline 4293 4294@example 4295 4296 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4297 4298@end example 4299 4300The simplest secure usage is to provide the secret via a file 4301 4302 # printf "letmein" > mypasswd.txt 4303 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4304 4305For greater security, AES-256-CBC should be used. To illustrate usage, 4306consider the openssl command line tool which can encrypt the data. Note 4307that when encrypting, the plaintext must be padded to the cipher block 4308size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4309 4310First a master key needs to be created in base64 encoding: 4311 4312@example 4313 # openssl rand -base64 32 > key.b64 4314 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4315@end example 4316 4317Each secret to be encrypted needs to have a random initialization vector 4318generated. These do not need to be kept secret 4319 4320@example 4321 # openssl rand -base64 16 > iv.b64 4322 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4323@end example 4324 4325The secret to be defined can now be encrypted, in this case we're 4326telling openssl to base64 encode the result, but it could be left 4327as raw bytes if desired. 4328 4329@example 4330 # SECRET=$(printf "letmein" | 4331 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4332@end example 4333 4334When launching QEMU, create a master secret pointing to @code{key.b64} 4335and specify that to be used to decrypt the user password. Pass the 4336contents of @code{iv.b64} to the second secret 4337 4338@example 4339 # $QEMU \ 4340 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4341 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4342 data=$SECRET,iv=$(<iv.b64) 4343@end example 4344 4345@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}] 4346 4347Create a Secure Encrypted Virtualization (SEV) guest object, which can be used 4348to provide the guest memory encryption support on AMD processors. 4349 4350When memory encryption is enabled, one of the physical address bit (aka the 4351C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos} 4352is used to provide the C-bit position. The C-bit position is Host family dependent 4353hence user must provide this value. On EPYC, the value should be 47. 4354 4355When memory encryption is enabled, we loose certain bits in physical address space. 4356The @option{reduced-phys-bits} is used to provide the number of bits we loose in 4357physical address space. Similar to C-bit, the value is Host family dependent. 4358On EPYC, the value should be 5. 4359 4360The @option{sev-device} provides the device file to use for communicating with 4361the SEV firmware running inside AMD Secure Processor. The default device is 4362'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are 4363created by CCP driver. 4364 4365The @option{policy} provides the guest policy to be enforced by the SEV firmware 4366and restrict what configuration and operational commands can be performed on this 4367guest by the hypervisor. The policy should be provided by the guest owner and is 4368bound to the guest and cannot be changed throughout the lifetime of the guest. 4369The default is 0. 4370 4371If guest @option{policy} allows sharing the key with another SEV guest then 4372@option{handle} can be use to provide handle of the guest from which to share 4373the key. 4374 4375The @option{dh-cert-file} and @option{session-file} provides the guest owner's 4376Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters 4377are used for establishing a cryptographic session with the guest owner to 4378negotiate keys used for attestation. The file must be encoded in base64. 4379 4380e.g to launch a SEV guest 4381@example 4382 # $QEMU \ 4383 ...... 4384 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ 4385 -machine ...,memory-encryption=sev0 4386 ..... 4387 4388@end example 4389 4390 4391@item -object authz-simple,id=@var{id},identity=@var{string} 4392 4393Create an authorization object that will control access to network services. 4394 4395The @option{identity} parameter is identifies the user and its format 4396depends on the network service that authorization object is associated 4397with. For authorizing based on TLS x509 certificates, the identity must 4398be the x509 distinguished name. Note that care must be taken to escape 4399any commas in the distinguished name. 4400 4401An example authorization object to validate a x509 distinguished name 4402would look like: 4403@example 4404 # $QEMU \ 4405 ... 4406 -object 'authz-simple,id=auth0,identity=CN=laptop.example.com,,O=Example Org,,L=London,,ST=London,,C=GB' \ 4407 ... 4408@end example 4409 4410Note the use of quotes due to the x509 distinguished name containing 4411whitespace, and escaping of ','. 4412 4413@item -object authz-listfile,id=@var{id},filename=@var{path},refresh=@var{yes|no} 4414 4415Create an authorization object that will control access to network services. 4416 4417The @option{filename} parameter is the fully qualified path to a file 4418containing the access control list rules in JSON format. 4419 4420An example set of rules that match against SASL usernames might look 4421like: 4422 4423@example 4424 @{ 4425 "rules": [ 4426 @{ "match": "fred", "policy": "allow", "format": "exact" @}, 4427 @{ "match": "bob", "policy": "allow", "format": "exact" @}, 4428 @{ "match": "danb", "policy": "deny", "format": "glob" @}, 4429 @{ "match": "dan*", "policy": "allow", "format": "exact" @}, 4430 ], 4431 "policy": "deny" 4432 @} 4433@end example 4434 4435When checking access the object will iterate over all the rules and 4436the first rule to match will have its @option{policy} value returned 4437as the result. If no rules match, then the default @option{policy} 4438value is returned. 4439 4440The rules can either be an exact string match, or they can use the 4441simple UNIX glob pattern matching to allow wildcards to be used. 4442 4443If @option{refresh} is set to true the file will be monitored 4444and automatically reloaded whenever its content changes. 4445 4446As with the @code{authz-simple} object, the format of the identity 4447strings being matched depends on the network service, but is usually 4448a TLS x509 distinguished name, or a SASL username. 4449 4450An example authorization object to validate a SASL username 4451would look like: 4452@example 4453 # $QEMU \ 4454 ... 4455 -object authz-simple,id=auth0,filename=/etc/qemu/vnc-sasl.acl,refresh=yes 4456 ... 4457@end example 4458 4459@item -object authz-pam,id=@var{id},service=@var{string} 4460 4461Create an authorization object that will control access to network services. 4462 4463The @option{service} parameter provides the name of a PAM service to use 4464for authorization. It requires that a file @code{/etc/pam.d/@var{service}} 4465exist to provide the configuration for the @code{account} subsystem. 4466 4467An example authorization object to validate a TLS x509 distinguished 4468name would look like: 4469 4470@example 4471 # $QEMU \ 4472 ... 4473 -object authz-pam,id=auth0,service=qemu-vnc 4474 ... 4475@end example 4476 4477There would then be a corresponding config file for PAM at 4478@code{/etc/pam.d/qemu-vnc} that contains: 4479 4480@example 4481account requisite pam_listfile.so item=user sense=allow \ 4482 file=/etc/qemu/vnc.allow 4483@end example 4484 4485Finally the @code{/etc/qemu/vnc.allow} file would contain 4486the list of x509 distingished names that are permitted 4487access 4488 4489@example 4490CN=laptop.example.com,O=Example Home,L=London,ST=London,C=GB 4491@end example 4492 4493 4494@end table 4495 4496ETEXI 4497 4498 4499HXCOMM This is the last statement. Insert new options before this line! 4500STEXI 4501@end table 4502ETEXI 4503
