1HXCOMM Use DEFHEADING() to define headings in both help text and texi 2HXCOMM Text between STEXI and ETEXI are copied to texi version and 3HXCOMM discarded from C version 4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to 5HXCOMM construct option structures, enums and help message for specified 6HXCOMM architectures. 7HXCOMM HXCOMM can be used for comments, discarded from both texi and C 8 9DEFHEADING(Standard options:) 10STEXI 11@table @option 12ETEXI 13 14DEF("help", 0, QEMU_OPTION_h, 15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL) 16STEXI 17@item -h 18@findex -h 19Display help and exit 20ETEXI 21 22DEF("version", 0, QEMU_OPTION_version, 23 "-version display version information and exit\n", QEMU_ARCH_ALL) 24STEXI 25@item -version 26@findex -version 27Display version information and exit 28ETEXI 29 30DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ 31 "-machine [type=]name[,prop[=value][,...]]\n" 32 " selects emulated machine ('-machine help' for list)\n" 33 " property accel=accel1[:accel2[:...]] selects accelerator\n" 34 " supported accelerators are kvm, xen, hax, hvf, whpx or tcg (default: tcg)\n" 35 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n" 36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n" 37 " kvm_shadow_mem=size of KVM shadow MMU in bytes\n" 38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 39 " mem-merge=on|off controls memory merge support (default: on)\n" 40 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n" 41 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" 42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" 43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" 44 " nvdimm=on|off controls NVDIMM support (default=off)\n" 45 " enforce-config-section=on|off enforce configuration section migration (default=off)\n" 46 " memory-encryption=@var{} memory encryption object to use (default=none)\n", 47 QEMU_ARCH_ALL) 48STEXI 49@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 50@findex -machine 51Select the emulated machine by @var{name}. Use @code{-machine help} to list 52available machines. 53 54For architectures which aim to support live migration compatibility 55across releases, each release will introduce a new versioned machine 56type. For example, the 2.8.0 release introduced machine types 57``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures. 58 59To allow live migration of guests from QEMU version 2.8.0, to QEMU 60version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8'' 61and ``pc-q35-2.8'' machines too. To allow users live migrating VMs 62to skip multiple intermediate releases when upgrading, new releases 63of QEMU will support machine types from many previous versions. 64 65Supported machine properties are: 66@table @option 67@item accel=@var{accels1}[:@var{accels2}[:...]] 68This is used to enable an accelerator. Depending on the target architecture, 69kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 70more than one accelerator specified, the next one is used if the previous one 71fails to initialize. 72@item kernel_irqchip=on|off 73Controls in-kernel irqchip support for the chosen accelerator when available. 74@item gfx_passthru=on|off 75Enables IGD GFX passthrough support for the chosen machine when available. 76@item vmport=on|off|auto 77Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 78value based on accel. For accel=xen the default is off otherwise the default 79is on. 80@item kvm_shadow_mem=size 81Defines the size of the KVM shadow MMU. 82@item dump-guest-core=on|off 83Include guest memory in a core dump. The default is on. 84@item mem-merge=on|off 85Enables or disables memory merge support. This feature, when supported by 86the host, de-duplicates identical memory pages among VMs instances 87(enabled by default). 88@item aes-key-wrap=on|off 89Enables or disables AES key wrapping support on s390-ccw hosts. This feature 90controls whether AES wrapping keys will be created to allow 91execution of AES cryptographic functions. The default is on. 92@item dea-key-wrap=on|off 93Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 94controls whether DEA wrapping keys will be created to allow 95execution of DEA cryptographic functions. The default is on. 96@item nvdimm=on|off 97Enables or disables NVDIMM support. The default is off. 98@item enforce-config-section=on|off 99If @option{enforce-config-section} is set to @var{on}, force migration 100code to send configuration section even if the machine-type sets the 101@option{migration.send-configuration} property to @var{off}. 102NOTE: this parameter is deprecated. Please use @option{-global} 103@option{migration.send-configuration}=@var{on|off} instead. 104@item memory-encryption=@var{} 105Memory encryption object to use. The default is none. 106@end table 107ETEXI 108 109HXCOMM Deprecated by -machine 110DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 111 112DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 113 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 114STEXI 115@item -cpu @var{model} 116@findex -cpu 117Select CPU model (@code{-cpu help} for list and additional feature selection) 118ETEXI 119 120DEF("accel", HAS_ARG, QEMU_OPTION_accel, 121 "-accel [accel=]accelerator[,thread=single|multi]\n" 122 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n" 123 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL) 124STEXI 125@item -accel @var{name}[,prop=@var{value}[,...]] 126@findex -accel 127This is used to enable an accelerator. Depending on the target architecture, 128kvm, xen, hax, hvf, whpx or tcg can be available. By default, tcg is used. If there is 129more than one accelerator specified, the next one is used if the previous one 130fails to initialize. 131@table @option 132@item thread=single|multi 133Controls number of TCG threads. When the TCG is multi-threaded there will be one 134thread per vCPU therefor taking advantage of additional host cores. The default 135is to enable multi-threading where both the back-end and front-ends support it and 136no incompatible TCG features have been enabled (e.g. icount/replay). 137@end table 138ETEXI 139 140DEF("smp", HAS_ARG, QEMU_OPTION_smp, 141 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 142 " set the number of CPUs to 'n' [default=1]\n" 143 " maxcpus= maximum number of total cpus, including\n" 144 " offline CPUs for hotplug, etc\n" 145 " cores= number of CPU cores on one socket\n" 146 " threads= number of threads on one CPU core\n" 147 " sockets= number of discrete sockets in the system\n", 148 QEMU_ARCH_ALL) 149STEXI 150@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 151@findex -smp 152Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 153CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 154to 4. 155For the PC target, the number of @var{cores} per socket, the number 156of @var{threads} per cores and the total number of @var{sockets} can be 157specified. Missing values will be computed. If any on the three values is 158given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 159specifies the maximum number of hotpluggable CPUs. 160ETEXI 161 162DEF("numa", HAS_ARG, QEMU_OPTION_numa, 163 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 164 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 165 "-numa dist,src=source,dst=destination,val=distance\n" 166 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n", 167 QEMU_ARCH_ALL) 168STEXI 169@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 170@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 171@itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance} 172@itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}] 173@findex -numa 174Define a NUMA node and assign RAM and VCPUs to it. 175Set the NUMA distance from a source node to a destination node. 176 177Legacy VCPU assignment uses @samp{cpus} option where 178@var{firstcpu} and @var{lastcpu} are CPU indexes. Each 179@samp{cpus} option represent a contiguous range of CPU indexes 180(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous 181set of VCPUs can be represented by providing multiple @samp{cpus} 182options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically 183split between them. 184 185For example, the following option assigns VCPUs 0, 1, 2 and 5 to 186a NUMA node: 187@example 188-numa node,cpus=0-2,cpus=5 189@end example 190 191@samp{cpu} option is a new alternative to @samp{cpus} option 192which uses @samp{socket-id|core-id|thread-id} properties to assign 193CPU objects to a @var{node} using topology layout properties of CPU. 194The set of properties is machine specific, and depends on used 195machine type/@samp{smp} options. It could be queried with 196@samp{hotpluggable-cpus} monitor command. 197@samp{node-id} property specifies @var{node} to which CPU object 198will be assigned, it's required for @var{node} to be declared 199with @samp{node} option before it's used with @samp{cpu} option. 200 201For example: 202@example 203-M pc \ 204-smp 1,sockets=2,maxcpus=2 \ 205-numa node,nodeid=0 -numa node,nodeid=1 \ 206-numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1 207@end example 208 209@samp{mem} assigns a given RAM amount to a node. @samp{memdev} 210assigns RAM from a given memory backend device to a node. If 211@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is 212split equally between them. 213 214@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, 215if one node uses @samp{memdev}, all of them have to use it. 216 217@var{source} and @var{destination} are NUMA node IDs. 218@var{distance} is the NUMA distance from @var{source} to @var{destination}. 219The distance from a node to itself is always 10. If any pair of nodes is 220given a distance, then all pairs must be given distances. Although, when 221distances are only given in one direction for each pair of nodes, then 222the distances in the opposite directions are assumed to be the same. If, 223however, an asymmetrical pair of distances is given for even one node 224pair, then all node pairs must be provided distance values for both 225directions, even when they are symmetrical. When a node is unreachable 226from another node, set the pair's distance to 255. 227 228Note that the -@option{numa} option doesn't allocate any of the 229specified resources, it just assigns existing resources to NUMA 230nodes. This means that one still has to use the @option{-m}, 231@option{-smp} options to allocate RAM and VCPUs respectively. 232 233ETEXI 234 235DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 236 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 237 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 238STEXI 239@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 240@findex -add-fd 241 242Add a file descriptor to an fd set. Valid options are: 243 244@table @option 245@item fd=@var{fd} 246This option defines the file descriptor of which a duplicate is added to fd set. 247The file descriptor cannot be stdin, stdout, or stderr. 248@item set=@var{set} 249This option defines the ID of the fd set to add the file descriptor to. 250@item opaque=@var{opaque} 251This option defines a free-form string that can be used to describe @var{fd}. 252@end table 253 254You can open an image using pre-opened file descriptors from an fd set: 255@example 256qemu-system-i386 257-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 258-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 259-drive file=/dev/fdset/2,index=0,media=disk 260@end example 261ETEXI 262 263DEF("set", HAS_ARG, QEMU_OPTION_set, 264 "-set group.id.arg=value\n" 265 " set <arg> parameter for item <id> of type <group>\n" 266 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 267STEXI 268@item -set @var{group}.@var{id}.@var{arg}=@var{value} 269@findex -set 270Set parameter @var{arg} for item @var{id} of type @var{group} 271ETEXI 272 273DEF("global", HAS_ARG, QEMU_OPTION_global, 274 "-global driver.property=value\n" 275 "-global driver=driver,property=property,value=value\n" 276 " set a global default for a driver property\n", 277 QEMU_ARCH_ALL) 278STEXI 279@item -global @var{driver}.@var{prop}=@var{value} 280@itemx -global driver=@var{driver},property=@var{property},value=@var{value} 281@findex -global 282Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 283 284@example 285qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img 286@end example 287 288In particular, you can use this to set driver properties for devices which are 289created automatically by the machine model. To create a device which is not 290created automatically and set properties on it, use -@option{device}. 291 292-global @var{driver}.@var{prop}=@var{value} is shorthand for -global 293driver=@var{driver},property=@var{prop},value=@var{value}. The 294longhand syntax works even when @var{driver} contains a dot. 295ETEXI 296 297DEF("boot", HAS_ARG, QEMU_OPTION_boot, 298 "-boot [order=drives][,once=drives][,menu=on|off]\n" 299 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 300 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 301 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 302 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 303 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 304 QEMU_ARCH_ALL) 305STEXI 306@item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}][,reboot-timeout=@var{rb_timeout}][,strict=on|off] 307@findex -boot 308Specify boot order @var{drives} as a string of drive letters. Valid 309drive letters depend on the target architecture. The x86 PC uses: a, b 310(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 311from network adapter 1-4), hard disk boot is the default. To apply a 312particular boot order only on the first startup, specify it via 313@option{once}. Note that the @option{order} or @option{once} parameter 314should not be used together with the @option{bootindex} property of 315devices, since the firmware implementations normally do not support both 316at the same time. 317 318Interactive boot menus/prompts can be enabled via @option{menu=on} as far 319as firmware/BIOS supports them. The default is non-interactive boot. 320 321A splash picture could be passed to bios, enabling user to show it as logo, 322when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 323supports them. Currently Seabios for X86 system support it. 324limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 325format(true color). The resolution should be supported by the SVGA mode, so 326the recommended is 320x240, 640x480, 800x640. 327 328A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 329when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 330reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 331system support it. 332 333Do strict boot via @option{strict=on} as far as firmware/BIOS 334supports it. This only effects when boot priority is changed by 335bootindex options. The default is non-strict boot. 336 337@example 338# try to boot from network first, then from hard disk 339qemu-system-i386 -boot order=nc 340# boot from CD-ROM first, switch back to default order after reboot 341qemu-system-i386 -boot once=d 342# boot with a splash picture for 5 seconds. 343qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 344@end example 345 346Note: The legacy format '-boot @var{drives}' is still supported but its 347use is discouraged as it may be removed from future versions. 348ETEXI 349 350DEF("m", HAS_ARG, QEMU_OPTION_m, 351 "-m [size=]megs[,slots=n,maxmem=size]\n" 352 " configure guest RAM\n" 353 " size: initial amount of guest memory\n" 354 " slots: number of hotplug slots (default: none)\n" 355 " maxmem: maximum amount of guest memory (default: none)\n" 356 "NOTE: Some architectures might enforce a specific granularity\n", 357 QEMU_ARCH_ALL) 358STEXI 359@item -m [size=]@var{megs}[,slots=n,maxmem=size] 360@findex -m 361Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 362Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 363megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 364could be used to set amount of hotpluggable memory slots and maximum amount of 365memory. Note that @var{maxmem} must be aligned to the page size. 366 367For example, the following command-line sets the guest startup RAM size to 3681GB, creates 3 slots to hotplug additional memory and sets the maximum 369memory the guest can reach to 4GB: 370 371@example 372qemu-system-x86_64 -m 1G,slots=3,maxmem=4G 373@end example 374 375If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 376be enabled and the guest startup RAM will never increase. 377ETEXI 378 379DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 380 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 381STEXI 382@item -mem-path @var{path} 383@findex -mem-path 384Allocate guest RAM from a temporarily created file in @var{path}. 385ETEXI 386 387DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 388 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 389 QEMU_ARCH_ALL) 390STEXI 391@item -mem-prealloc 392@findex -mem-prealloc 393Preallocate memory when using -mem-path. 394ETEXI 395 396DEF("k", HAS_ARG, QEMU_OPTION_k, 397 "-k language use keyboard layout (for example 'fr' for French)\n", 398 QEMU_ARCH_ALL) 399STEXI 400@item -k @var{language} 401@findex -k 402Use keyboard layout @var{language} (for example @code{fr} for 403French). This option is only needed where it is not easy to get raw PC 404keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses 405display). You don't normally need to use it on PC/Linux or PC/Windows 406hosts. 407 408The available layouts are: 409@example 410ar de-ch es fo fr-ca hu ja mk no pt-br sv 411da en-gb et fr fr-ch is lt nl pl ru th 412de en-us fi fr-be hr it lv nl-be pt sl tr 413@end example 414 415The default is @code{en-us}. 416ETEXI 417 418 419DEF("audio-help", 0, QEMU_OPTION_audio_help, 420 "-audio-help print list of audio drivers and their options\n", 421 QEMU_ARCH_ALL) 422STEXI 423@item -audio-help 424@findex -audio-help 425Will show the audio subsystem help: list of drivers, tunable 426parameters. 427ETEXI 428 429DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 430 "-soundhw c1,... enable audio support\n" 431 " and only specified sound cards (comma separated list)\n" 432 " use '-soundhw help' to get the list of supported cards\n" 433 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 434STEXI 435@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 436@findex -soundhw 437Enable audio and selected sound hardware. Use 'help' to print all 438available sound hardware. 439 440@example 441qemu-system-i386 -soundhw sb16,adlib disk.img 442qemu-system-i386 -soundhw es1370 disk.img 443qemu-system-i386 -soundhw ac97 disk.img 444qemu-system-i386 -soundhw hda disk.img 445qemu-system-i386 -soundhw all disk.img 446qemu-system-i386 -soundhw help 447@end example 448 449Note that Linux's i810_audio OSS kernel (for AC97) module might 450require manually specifying clocking. 451 452@example 453modprobe i810_audio clocking=48000 454@end example 455ETEXI 456 457DEF("device", HAS_ARG, QEMU_OPTION_device, 458 "-device driver[,prop[=value][,...]]\n" 459 " add device (based on driver)\n" 460 " prop=value,... sets driver properties\n" 461 " use '-device help' to print all possible drivers\n" 462 " use '-device driver,help' to print all possible properties\n", 463 QEMU_ARCH_ALL) 464STEXI 465@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 466@findex -device 467Add device @var{driver}. @var{prop}=@var{value} sets driver 468properties. Valid properties depend on the driver. To get help on 469possible drivers and properties, use @code{-device help} and 470@code{-device @var{driver},help}. 471 472Some drivers are: 473@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}] 474 475Add an IPMI BMC. This is a simulation of a hardware management 476interface processor that normally sits on a system. It provides 477a watchdog and the ability to reset and power control the system. 478You need to connect this to an IPMI interface to make it useful 479 480The IPMI slave address to use for the BMC. The default is 0x20. 481This address is the BMC's address on the I2C network of management 482controllers. If you don't know what this means, it is safe to ignore 483it. 484 485@table @option 486@item bmc=@var{id} 487The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 488@item slave_addr=@var{val} 489Define slave address to use for the BMC. The default is 0x20. 490@item sdrfile=@var{file} 491file containing raw Sensor Data Records (SDR) data. The default is none. 492@item fruareasize=@var{val} 493size of a Field Replaceable Unit (FRU) area. The default is 1024. 494@item frudatafile=@var{file} 495file containing raw Field Replaceable Unit (FRU) inventory data. The default is none. 496@end table 497 498@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 499 500Add a connection to an external IPMI BMC simulator. Instead of 501locally emulating the BMC like the above item, instead connect 502to an external entity that provides the IPMI services. 503 504A connection is made to an external BMC simulator. If you do this, it 505is strongly recommended that you use the "reconnect=" chardev option 506to reconnect to the simulator if the connection is lost. Note that if 507this is not used carefully, it can be a security issue, as the 508interface has the ability to send resets, NMIs, and power off the VM. 509It's best if QEMU makes a connection to an external simulator running 510on a secure port on localhost, so neither the simulator nor QEMU is 511exposed to any outside network. 512 513See the "lanserv/README.vm" file in the OpenIPMI library for more 514details on the external interface. 515 516@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 517 518Add a KCS IPMI interafce on the ISA bus. This also adds a 519corresponding ACPI and SMBIOS entries, if appropriate. 520 521@table @option 522@item bmc=@var{id} 523The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 524@item ioport=@var{val} 525Define the I/O address of the interface. The default is 0xca0 for KCS. 526@item irq=@var{val} 527Define the interrupt to use. The default is 5. To disable interrupts, 528set this to 0. 529@end table 530 531@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 532 533Like the KCS interface, but defines a BT interface. The default port is 5340xe4 and the default interrupt is 5. 535 536ETEXI 537 538DEF("name", HAS_ARG, QEMU_OPTION_name, 539 "-name string1[,process=string2][,debug-threads=on|off]\n" 540 " set the name of the guest\n" 541 " string1 sets the window title and string2 the process name (on Linux)\n" 542 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 543 " NOTE: The thread names are for debugging and not a stable API.\n", 544 QEMU_ARCH_ALL) 545STEXI 546@item -name @var{name} 547@findex -name 548Sets the @var{name} of the guest. 549This name will be displayed in the SDL window caption. 550The @var{name} will also be used for the VNC server. 551Also optionally set the top visible process name in Linux. 552Naming of individual threads can also be enabled on Linux to aid debugging. 553ETEXI 554 555DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 556 "-uuid %08x-%04x-%04x-%04x-%012x\n" 557 " specify machine UUID\n", QEMU_ARCH_ALL) 558STEXI 559@item -uuid @var{uuid} 560@findex -uuid 561Set system UUID. 562ETEXI 563 564STEXI 565@end table 566ETEXI 567DEFHEADING() 568 569DEFHEADING(Block device options:) 570STEXI 571@table @option 572ETEXI 573 574DEF("fda", HAS_ARG, QEMU_OPTION_fda, 575 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 576DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 577STEXI 578@item -fda @var{file} 579@itemx -fdb @var{file} 580@findex -fda 581@findex -fdb 582Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 583ETEXI 584 585DEF("hda", HAS_ARG, QEMU_OPTION_hda, 586 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 587DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 588DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 589 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 590DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 591STEXI 592@item -hda @var{file} 593@itemx -hdb @var{file} 594@itemx -hdc @var{file} 595@itemx -hdd @var{file} 596@findex -hda 597@findex -hdb 598@findex -hdc 599@findex -hdd 600Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 601ETEXI 602 603DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 604 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 605 QEMU_ARCH_ALL) 606STEXI 607@item -cdrom @var{file} 608@findex -cdrom 609Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 610@option{-cdrom} at the same time). You can use the host CD-ROM by 611using @file{/dev/cdrom} as filename (@pxref{host_drives}). 612ETEXI 613 614DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev, 615 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n" 616 " [,cache.direct=on|off][,cache.no-flush=on|off]\n" 617 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n" 618 " [,driver specific parameters...]\n" 619 " configure a block backend\n", QEMU_ARCH_ALL) 620STEXI 621@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]] 622@findex -blockdev 623 624Define a new block driver node. Some of the options apply to all block drivers, 625other options are only accepted for a specific block driver. See below for a 626list of generic options and options for the most common block drivers. 627 628Options that expect a reference to another node (e.g. @code{file}) can be 629given in two ways. Either you specify the node name of an already existing node 630(file=@var{node-name}), or you define a new node inline, adding options 631for the referenced node after a dot (file.filename=@var{path},file.aio=native). 632 633A block driver node created with @option{-blockdev} can be used for a guest 634device by specifying its node name for the @code{drive} property in a 635@option{-device} argument that defines a block device. 636 637@table @option 638@item Valid options for any block driver node: 639 640@table @code 641@item driver 642Specifies the block driver to use for the given node. 643@item node-name 644This defines the name of the block driver node by which it will be referenced 645later. The name must be unique, i.e. it must not match the name of a different 646block driver node, or (if you use @option{-drive} as well) the ID of a drive. 647 648If no node name is specified, it is automatically generated. The generated node 649name is not intended to be predictable and changes between QEMU invocations. 650For the top level, an explicit node name must be specified. 651@item read-only 652Open the node read-only. Guest write attempts will fail. 653@item cache.direct 654The host page cache can be avoided with @option{cache.direct=on}. This will 655attempt to do disk IO directly to the guest's memory. QEMU may still perform an 656internal copy of the data. 657@item cache.no-flush 658In case you don't care about data integrity over host failures, you can use 659@option{cache.no-flush=on}. This option tells QEMU that it never needs to write 660any data to the disk but can instead keep things in cache. If anything goes 661wrong, like your host losing power, the disk storage getting disconnected 662accidentally, etc. your image will most probably be rendered unusable. 663@item discard=@var{discard} 664@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls 665whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are 666ignored or passed to the filesystem. Some machine types may not support 667discard requests. 668@item detect-zeroes=@var{detect-zeroes} 669@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 670conversion of plain zero writes by the OS to driver specific optimized 671zero write commands. You may even choose "unmap" if @var{discard} is set 672to "unmap" to allow a zero write to be converted to an @code{unmap} operation. 673@end table 674 675@item Driver-specific options for @code{file} 676 677This is the protocol-level block driver for accessing regular files. 678 679@table @code 680@item filename 681The path to the image file in the local filesystem 682@item aio 683Specifies the AIO backend (threads/native, default: threads) 684@item locking 685Specifies whether the image file is protected with Linux OFD / POSIX locks. The 686default is to use the Linux Open File Descriptor API if available, otherwise no 687lock is applied. (auto/on/off, default: auto) 688@end table 689Example: 690@example 691-blockdev driver=file,node-name=disk,filename=disk.img 692@end example 693 694@item Driver-specific options for @code{raw} 695 696This is the image format block driver for raw images. It is usually 697stacked on top of a protocol level block driver such as @code{file}. 698 699@table @code 700@item file 701Reference to or definition of the data source block driver node 702(e.g. a @code{file} driver node) 703@end table 704Example 1: 705@example 706-blockdev driver=file,node-name=disk_file,filename=disk.img 707-blockdev driver=raw,node-name=disk,file=disk_file 708@end example 709Example 2: 710@example 711-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img 712@end example 713 714@item Driver-specific options for @code{qcow2} 715 716This is the image format block driver for qcow2 images. It is usually 717stacked on top of a protocol level block driver such as @code{file}. 718 719@table @code 720@item file 721Reference to or definition of the data source block driver node 722(e.g. a @code{file} driver node) 723 724@item backing 725Reference to or definition of the backing file block device (default is taken 726from the image file). It is allowed to pass @code{null} here in order to disable 727the default backing file. 728 729@item lazy-refcounts 730Whether to enable the lazy refcounts feature (on/off; default is taken from the 731image file) 732 733@item cache-size 734The maximum total size of the L2 table and refcount block caches in bytes 735(default: the sum of l2-cache-size and refcount-cache-size) 736 737@item l2-cache-size 738The maximum size of the L2 table cache in bytes 739(default: if cache-size is not specified - 32M on Linux platforms, and 8M on 740non-Linux platforms; otherwise, as large as possible within the cache-size, 741while permitting the requested or the minimal refcount cache size) 742 743@item refcount-cache-size 744The maximum size of the refcount block cache in bytes 745(default: 4 times the cluster size; or if cache-size is specified, the part of 746it which is not used for the L2 cache) 747 748@item cache-clean-interval 749Clean unused entries in the L2 and refcount caches. The interval is in seconds. 750The default value is 600 on supporting platforms, and 0 on other platforms. 751Setting it to 0 disables this feature. 752 753@item pass-discard-request 754Whether discard requests to the qcow2 device should be forwarded to the data 755source (on/off; default: on if discard=unmap is specified, off otherwise) 756 757@item pass-discard-snapshot 758Whether discard requests for the data source should be issued when a snapshot 759operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off; 760default: on) 761 762@item pass-discard-other 763Whether discard requests for the data source should be issued on other 764occasions where a cluster gets freed (on/off; default: off) 765 766@item overlap-check 767Which overlap checks to perform for writes to the image 768(none/constant/cached/all; default: cached). For details or finer 769granularity control refer to the QAPI documentation of @code{blockdev-add}. 770@end table 771 772Example 1: 773@example 774-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2 775-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216 776@end example 777Example 2: 778@example 779-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2 780@end example 781 782@item Driver-specific options for other drivers 783Please refer to the QAPI documentation of the @code{blockdev-add} QMP command. 784 785@end table 786 787ETEXI 788 789DEF("drive", HAS_ARG, QEMU_OPTION_drive, 790 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 791 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 792 " [,snapshot=on|off][,rerror=ignore|stop|report]\n" 793 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 794 " [,readonly=on|off][,copy-on-read=on|off]\n" 795 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 796 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 797 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 798 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 799 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 800 " [[,iops_size=is]]\n" 801 " [[,group=g]]\n" 802 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 803STEXI 804@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 805@findex -drive 806 807Define a new drive. This includes creating a block driver node (the backend) as 808well as a guest device, and is mostly a shortcut for defining the corresponding 809@option{-blockdev} and @option{-device} options. 810 811@option{-drive} accepts all options that are accepted by @option{-blockdev}. In 812addition, it knows the following options: 813 814@table @option 815@item file=@var{file} 816This option defines which disk image (@pxref{disk_images}) to use with 817this drive. If the filename contains comma, you must double it 818(for instance, "file=my,,file" to use file "my,file"). 819 820Special files such as iSCSI devices can be specified using protocol 821specific URLs. See the section for "Device URL Syntax" for more information. 822@item if=@var{interface} 823This option defines on which type on interface the drive is connected. 824Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none. 825@item bus=@var{bus},unit=@var{unit} 826These options define where is connected the drive by defining the bus number and 827the unit id. 828@item index=@var{index} 829This option defines where is connected the drive by using an index in the list 830of available connectors of a given interface type. 831@item media=@var{media} 832This option defines the type of the media: disk or cdrom. 833@item snapshot=@var{snapshot} 834@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 835(see @option{-snapshot}). 836@item cache=@var{cache} 837@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" 838and controls how the host cache is used to access block data. This is a 839shortcut that sets the @option{cache.direct} and @option{cache.no-flush} 840options (as in @option{-blockdev}), and additionally @option{cache.writeback}, 841which provides a default for the @option{write-cache} option of block guest 842devices (as in @option{-device}). The modes correspond to the following 843settings: 844 845@c Our texi2pod.pl script doesn't support @multitable, so fall back to using 846@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage 847@c and the HTML output. 848@example 849@ │ cache.writeback cache.direct cache.no-flush 850─────────────┼───────────────────────────────────────────────── 851writeback │ on off off 852none │ on on off 853writethrough │ off off off 854directsync │ off on off 855unsafe │ on off on 856@end example 857 858The default mode is @option{cache=writeback}. 859 860@item aio=@var{aio} 861@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 862@item format=@var{format} 863Specify which disk @var{format} will be used rather than detecting 864the format. Can be used to specify format=raw to avoid interpreting 865an untrusted format header. 866@item werror=@var{action},rerror=@var{action} 867Specify which @var{action} to take on write and read errors. Valid actions are: 868"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 869"report" (report the error to the guest), "enospc" (pause QEMU only if the 870host disk is full; report the error to the guest otherwise). 871The default setting is @option{werror=enospc} and @option{rerror=report}. 872@item copy-on-read=@var{copy-on-read} 873@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 874file sectors into the image file. 875@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w} 876Specify bandwidth throttling limits in bytes per second, either for all request 877types or for reads or writes only. Small values can lead to timeouts or hangs 878inside the guest. A safe minimum for disks is 2 MB/s. 879@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm} 880Specify bursts in bytes per second, either for all request types or for reads 881or writes only. Bursts allow the guest I/O to spike above the limit 882temporarily. 883@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w} 884Specify request rate limits in requests per second, either for all request 885types or for reads or writes only. 886@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm} 887Specify bursts in requests per second, either for all request types or for reads 888or writes only. Bursts allow the guest I/O to spike above the limit 889temporarily. 890@item iops_size=@var{is} 891Let every @var{is} bytes of a request count as a new request for iops 892throttling purposes. Use this option to prevent guests from circumventing iops 893limits by sending fewer but larger requests. 894@item group=@var{g} 895Join a throttling quota group with given name @var{g}. All drives that are 896members of the same group are accounted for together. Use this option to 897prevent guests from circumventing throttling limits by using many small disks 898instead of a single larger disk. 899@end table 900 901By default, the @option{cache.writeback=on} mode is used. It will report data 902writes as completed as soon as the data is present in the host page cache. 903This is safe as long as your guest OS makes sure to correctly flush disk caches 904where needed. If your guest OS does not handle volatile disk write caches 905correctly and your host crashes or loses power, then the guest may experience 906data corruption. 907 908For such guests, you should consider using @option{cache.writeback=off}. This 909means that the host page cache will be used to read and write data, but write 910notification will be sent to the guest only after QEMU has made sure to flush 911each write to the disk. Be aware that this has a major impact on performance. 912 913When using the @option{-snapshot} option, unsafe caching is always used. 914 915Copy-on-read avoids accessing the same backing file sectors repeatedly and is 916useful when the backing file is over a slow network. By default copy-on-read 917is off. 918 919Instead of @option{-cdrom} you can use: 920@example 921qemu-system-i386 -drive file=file,index=2,media=cdrom 922@end example 923 924Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 925use: 926@example 927qemu-system-i386 -drive file=file,index=0,media=disk 928qemu-system-i386 -drive file=file,index=1,media=disk 929qemu-system-i386 -drive file=file,index=2,media=disk 930qemu-system-i386 -drive file=file,index=3,media=disk 931@end example 932 933You can open an image using pre-opened file descriptors from an fd set: 934@example 935qemu-system-i386 936-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 937-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 938-drive file=/dev/fdset/2,index=0,media=disk 939@end example 940 941You can connect a CDROM to the slave of ide0: 942@example 943qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 944@end example 945 946If you don't specify the "file=" argument, you define an empty drive: 947@example 948qemu-system-i386 -drive if=ide,index=1,media=cdrom 949@end example 950 951Instead of @option{-fda}, @option{-fdb}, you can use: 952@example 953qemu-system-i386 -drive file=file,index=0,if=floppy 954qemu-system-i386 -drive file=file,index=1,if=floppy 955@end example 956 957By default, @var{interface} is "ide" and @var{index} is automatically 958incremented: 959@example 960qemu-system-i386 -drive file=a -drive file=b" 961@end example 962is interpreted like: 963@example 964qemu-system-i386 -hda a -hdb b 965@end example 966ETEXI 967 968DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 969 "-mtdblock file use 'file' as on-board Flash memory image\n", 970 QEMU_ARCH_ALL) 971STEXI 972@item -mtdblock @var{file} 973@findex -mtdblock 974Use @var{file} as on-board Flash memory image. 975ETEXI 976 977DEF("sd", HAS_ARG, QEMU_OPTION_sd, 978 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 979STEXI 980@item -sd @var{file} 981@findex -sd 982Use @var{file} as SecureDigital card image. 983ETEXI 984 985DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 986 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 987STEXI 988@item -pflash @var{file} 989@findex -pflash 990Use @var{file} as a parallel flash image. 991ETEXI 992 993DEF("snapshot", 0, QEMU_OPTION_snapshot, 994 "-snapshot write to temporary files instead of disk image files\n", 995 QEMU_ARCH_ALL) 996STEXI 997@item -snapshot 998@findex -snapshot 999Write to temporary files instead of disk image files. In this case, 1000the raw disk image you use is not written back. You can however force 1001the write back by pressing @key{C-a s} (@pxref{disk_images}). 1002ETEXI 1003 1004DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 1005 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 1006 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n" 1007 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n" 1008 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n" 1009 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n" 1010 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n" 1011 " [[,throttling.iops-size=is]]\n", 1012 QEMU_ARCH_ALL) 1013 1014STEXI 1015 1016@item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}] 1017@findex -fsdev 1018Define a new file system device. Valid options are: 1019@table @option 1020@item @var{fsdriver} 1021This option specifies the fs driver backend to use. 1022Currently "local" 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 sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 1215 " [,window_close=on|off][,gl=on|core|es|off]\n" 1216 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 1217 "-display vnc=<display>[,<optargs>]\n" 1218 "-display curses\n" 1219 "-display none\n" 1220 "-display egl-headless[,rendernode=<file>]" 1221 " select display type\n" 1222 "The default display is equivalent to\n" 1223#if defined(CONFIG_GTK) 1224 "\t\"-display gtk\"\n" 1225#elif defined(CONFIG_SDL) 1226 "\t\"-display sdl\"\n" 1227#elif defined(CONFIG_COCOA) 1228 "\t\"-display cocoa\"\n" 1229#elif defined(CONFIG_VNC) 1230 "\t\"-vnc localhost:0,to=99,id=default\"\n" 1231#else 1232 "\t\"-display none\"\n" 1233#endif 1234 , QEMU_ARCH_ALL) 1235STEXI 1236@item -display @var{type} 1237@findex -display 1238Select type of display to use. This option is a replacement for the 1239old style -sdl/-curses/... options. Valid values for @var{type} are 1240@table @option 1241@item sdl 1242Display video output via SDL (usually in a separate graphics 1243window; see the SDL documentation for other possibilities). 1244@item curses 1245Display video output via curses. For graphics device models which 1246support a text mode, QEMU can display this output using a 1247curses/ncurses interface. Nothing is displayed when the graphics 1248device is in graphical mode or if the graphics device does not support 1249a text mode. Generally only the VGA device models support text mode. 1250@item none 1251Do not display video output. The guest will still see an emulated 1252graphics card, but its output will not be displayed to the QEMU 1253user. This option differs from the -nographic option in that it 1254only affects what is done with video output; -nographic also changes 1255the destination of the serial and parallel port data. 1256@item gtk 1257Display video output in a GTK window. This interface provides drop-down 1258menus and other UI elements to configure and control the VM during 1259runtime. 1260@item vnc 1261Start a VNC server on display <arg> 1262@item egl-headless 1263Offload all OpenGL operations to a local DRI device. For any graphical display, 1264this display needs to be paired with either VNC or SPICE displays. 1265@end table 1266ETEXI 1267 1268DEF("nographic", 0, QEMU_OPTION_nographic, 1269 "-nographic disable graphical output and redirect serial I/Os to console\n", 1270 QEMU_ARCH_ALL) 1271STEXI 1272@item -nographic 1273@findex -nographic 1274Normally, if QEMU is compiled with graphical window support, it displays 1275output such as guest graphics, guest console, and the QEMU monitor in a 1276window. With this option, you can totally disable graphical output so 1277that QEMU is a simple command line application. The emulated serial port 1278is redirected on the console and muxed with the monitor (unless 1279redirected elsewhere explicitly). Therefore, you can still use QEMU to 1280debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1281switching between the console and monitor. 1282ETEXI 1283 1284DEF("curses", 0, QEMU_OPTION_curses, 1285 "-curses shorthand for -display curses\n", 1286 QEMU_ARCH_ALL) 1287STEXI 1288@item -curses 1289@findex -curses 1290Normally, if QEMU is compiled with graphical window support, it displays 1291output such as guest graphics, guest console, and the QEMU monitor in a 1292window. With this option, QEMU can display the VGA output when in text 1293mode using a curses/ncurses interface. Nothing is displayed in graphical 1294mode. 1295ETEXI 1296 1297DEF("no-frame", 0, QEMU_OPTION_no_frame, 1298 "-no-frame open SDL window without a frame and window decorations\n", 1299 QEMU_ARCH_ALL) 1300STEXI 1301@item -no-frame 1302@findex -no-frame 1303Do not use decorations for SDL windows and start them using the whole 1304available screen space. This makes the using QEMU in a dedicated desktop 1305workspace more convenient. 1306ETEXI 1307 1308DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1309 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1310 QEMU_ARCH_ALL) 1311STEXI 1312@item -alt-grab 1313@findex -alt-grab 1314Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1315affects the special keys (for fullscreen, monitor-mode switching, etc). 1316ETEXI 1317 1318DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1319 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1320 QEMU_ARCH_ALL) 1321STEXI 1322@item -ctrl-grab 1323@findex -ctrl-grab 1324Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1325affects the special keys (for fullscreen, monitor-mode switching, etc). 1326ETEXI 1327 1328DEF("no-quit", 0, QEMU_OPTION_no_quit, 1329 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1330STEXI 1331@item -no-quit 1332@findex -no-quit 1333Disable SDL window close capability. 1334ETEXI 1335 1336DEF("sdl", 0, QEMU_OPTION_sdl, 1337 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1338STEXI 1339@item -sdl 1340@findex -sdl 1341Enable SDL. 1342ETEXI 1343 1344DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1345 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1346 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1347 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1348 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1349 " [,tls-ciphers=<list>]\n" 1350 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1351 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1352 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1353 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1354 " [,jpeg-wan-compression=[auto|never|always]]\n" 1355 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1356 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1357 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1358 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1359 " [,gl=[on|off]][,rendernode=<file>]\n" 1360 " enable spice\n" 1361 " at least one of {port, tls-port} is mandatory\n", 1362 QEMU_ARCH_ALL) 1363STEXI 1364@item -spice @var{option}[,@var{option}[,...]] 1365@findex -spice 1366Enable the spice remote desktop protocol. Valid options are 1367 1368@table @option 1369 1370@item port=<nr> 1371Set the TCP port spice is listening on for plaintext channels. 1372 1373@item addr=<addr> 1374Set the IP address spice is listening on. Default is any address. 1375 1376@item ipv4 1377@itemx ipv6 1378@itemx unix 1379Force using the specified IP version. 1380 1381@item password=<secret> 1382Set the password you need to authenticate. 1383 1384@item sasl 1385Require that the client use SASL to authenticate with the spice. 1386The exact choice of authentication method used is controlled from the 1387system / user's SASL configuration file for the 'qemu' service. This 1388is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1389unprivileged user, an environment variable SASL_CONF_PATH can be used 1390to make it search alternate locations for the service config. 1391While some SASL auth methods can also provide data encryption (eg GSSAPI), 1392it is recommended that SASL always be combined with the 'tls' and 1393'x509' settings to enable use of SSL and server certificates. This 1394ensures a data encryption preventing compromise of authentication 1395credentials. 1396 1397@item disable-ticketing 1398Allow client connects without authentication. 1399 1400@item disable-copy-paste 1401Disable copy paste between the client and the guest. 1402 1403@item disable-agent-file-xfer 1404Disable spice-vdagent based file-xfer between the client and the guest. 1405 1406@item tls-port=<nr> 1407Set the TCP port spice is listening on for encrypted channels. 1408 1409@item x509-dir=<dir> 1410Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1411 1412@item x509-key-file=<file> 1413@itemx x509-key-password=<file> 1414@itemx x509-cert-file=<file> 1415@itemx x509-cacert-file=<file> 1416@itemx x509-dh-key-file=<file> 1417The x509 file names can also be configured individually. 1418 1419@item tls-ciphers=<list> 1420Specify which ciphers to use. 1421 1422@item tls-channel=[main|display|cursor|inputs|record|playback] 1423@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1424Force specific channel to be used with or without TLS encryption. The 1425options can be specified multiple times to configure multiple 1426channels. The special name "default" can be used to set the default 1427mode. For channels which are not explicitly forced into one mode the 1428spice client is allowed to pick tls/plaintext as he pleases. 1429 1430@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1431Configure image compression (lossless). 1432Default is auto_glz. 1433 1434@item jpeg-wan-compression=[auto|never|always] 1435@itemx zlib-glz-wan-compression=[auto|never|always] 1436Configure wan image compression (lossy for slow links). 1437Default is auto. 1438 1439@item streaming-video=[off|all|filter] 1440Configure video stream detection. Default is off. 1441 1442@item agent-mouse=[on|off] 1443Enable/disable passing mouse events via vdagent. Default is on. 1444 1445@item playback-compression=[on|off] 1446Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1447 1448@item seamless-migration=[on|off] 1449Enable/disable spice seamless migration. Default is off. 1450 1451@item gl=[on|off] 1452Enable/disable OpenGL context. Default is off. 1453 1454@item rendernode=<file> 1455DRM render node for OpenGL rendering. If not specified, it will pick 1456the first available. (Since 2.9) 1457 1458@end table 1459ETEXI 1460 1461DEF("portrait", 0, QEMU_OPTION_portrait, 1462 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1463 QEMU_ARCH_ALL) 1464STEXI 1465@item -portrait 1466@findex -portrait 1467Rotate graphical output 90 deg left (only PXA LCD). 1468ETEXI 1469 1470DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1471 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1472 QEMU_ARCH_ALL) 1473STEXI 1474@item -rotate @var{deg} 1475@findex -rotate 1476Rotate graphical output some deg left (only PXA LCD). 1477ETEXI 1478 1479DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1480 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1481 " select video card type\n", QEMU_ARCH_ALL) 1482STEXI 1483@item -vga @var{type} 1484@findex -vga 1485Select type of VGA card to emulate. Valid values for @var{type} are 1486@table @option 1487@item cirrus 1488Cirrus Logic GD5446 Video card. All Windows versions starting from 1489Windows 95 should recognize and use this graphic card. For optimal 1490performances, use 16 bit color depth in the guest and the host OS. 1491(This card was the default before QEMU 2.2) 1492@item std 1493Standard VGA card with Bochs VBE extensions. If your guest OS 1494supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1495to use high resolution modes (>= 1280x1024x16) then you should use 1496this option. (This card is the default since QEMU 2.2) 1497@item vmware 1498VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1499recent XFree86/XOrg server or Windows guest with a driver for this 1500card. 1501@item qxl 1502QXL paravirtual graphic card. It is VGA compatible (including VESA 15032.0 VBE support). Works best with qxl guest drivers installed though. 1504Recommended choice when using the spice protocol. 1505@item tcx 1506(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1507sun4m machines and offers both 8-bit and 24-bit colour depths at a 1508fixed resolution of 1024x768. 1509@item cg3 1510(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1511for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1512resolutions aimed at people wishing to run older Solaris versions. 1513@item virtio 1514Virtio VGA card. 1515@item none 1516Disable VGA card. 1517@end table 1518ETEXI 1519 1520DEF("full-screen", 0, QEMU_OPTION_full_screen, 1521 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1522STEXI 1523@item -full-screen 1524@findex -full-screen 1525Start in full screen. 1526ETEXI 1527 1528DEF("g", 1, QEMU_OPTION_g , 1529 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1530 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1531STEXI 1532@item -g @var{width}x@var{height}[x@var{depth}] 1533@findex -g 1534Set the initial graphical resolution and depth (PPC, SPARC only). 1535ETEXI 1536 1537DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1538 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1539STEXI 1540@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1541@findex -vnc 1542Normally, if QEMU is compiled with graphical window support, it displays 1543output such as guest graphics, guest console, and the QEMU monitor in a 1544window. With this option, you can have QEMU listen on VNC display 1545@var{display} and redirect the VGA display over the VNC session. It is 1546very useful to enable the usb tablet device when using this option 1547(option @option{-device usb-tablet}). When using the VNC display, you 1548must use the @option{-k} parameter to set the keyboard layout if you are 1549not using en-us. Valid syntax for the @var{display} is 1550 1551@table @option 1552 1553@item to=@var{L} 1554 1555With this option, QEMU will try next available VNC @var{display}s, until the 1556number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1557available, e.g. port 5900+@var{display} is already used by another 1558application. By default, to=0. 1559 1560@item @var{host}:@var{d} 1561 1562TCP connections will only be allowed from @var{host} on display @var{d}. 1563By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1564be omitted in which case the server will accept connections from any host. 1565 1566@item unix:@var{path} 1567 1568Connections will be allowed over UNIX domain sockets where @var{path} is the 1569location of a unix socket to listen for connections on. 1570 1571@item none 1572 1573VNC is initialized but not started. The monitor @code{change} command 1574can be used to later start the VNC server. 1575 1576@end table 1577 1578Following the @var{display} value there may be one or more @var{option} flags 1579separated by commas. Valid options are 1580 1581@table @option 1582 1583@item reverse 1584 1585Connect to a listening VNC client via a ``reverse'' connection. The 1586client is specified by the @var{display}. For reverse network 1587connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1588is a TCP port number, not a display number. 1589 1590@item websocket 1591 1592Opens an additional TCP listening port dedicated to VNC Websocket connections. 1593If a bare @var{websocket} option is given, the Websocket port is 15945700+@var{display}. An alternative port can be specified with the 1595syntax @code{websocket}=@var{port}. 1596 1597If @var{host} is specified connections will only be allowed from this host. 1598It is possible to control the websocket listen address independently, using 1599the syntax @code{websocket}=@var{host}:@var{port}. 1600 1601If no TLS credentials are provided, the websocket connection runs in 1602unencrypted mode. If TLS credentials are provided, the websocket connection 1603requires encrypted client connections. 1604 1605@item password 1606 1607Require that password based authentication is used for client connections. 1608 1609The password must be set separately using the @code{set_password} command in 1610the @ref{pcsys_monitor}. The syntax to change your password is: 1611@code{set_password <protocol> <password>} where <protocol> could be either 1612"vnc" or "spice". 1613 1614If you would like to change <protocol> password expiration, you should use 1615@code{expire_password <protocol> <expiration-time>} where expiration time could 1616be one of the following options: now, never, +seconds or UNIX time of 1617expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1618to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1619date and time). 1620 1621You can also use keywords "now" or "never" for the expiration time to 1622allow <protocol> password to expire immediately or never expire. 1623 1624@item tls-creds=@var{ID} 1625 1626Provides the ID of a set of TLS credentials to use to secure the 1627VNC server. They will apply to both the normal VNC server socket 1628and the websocket socket (if enabled). Setting TLS credentials 1629will cause the VNC server socket to enable the VeNCrypt auth 1630mechanism. The credentials should have been previously created 1631using the @option{-object tls-creds} argument. 1632 1633@item sasl 1634 1635Require that the client use SASL to authenticate with the VNC server. 1636The exact choice of authentication method used is controlled from the 1637system / user's SASL configuration file for the 'qemu' service. This 1638is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1639unprivileged user, an environment variable SASL_CONF_PATH can be used 1640to make it search alternate locations for the service config. 1641While some SASL auth methods can also provide data encryption (eg GSSAPI), 1642it is recommended that SASL always be combined with the 'tls' and 1643'x509' settings to enable use of SSL and server certificates. This 1644ensures a data encryption preventing compromise of authentication 1645credentials. See the @ref{vnc_security} section for details on using 1646SASL authentication. 1647 1648@item acl 1649 1650Turn on access control lists for checking of the x509 client certificate 1651and SASL party. For x509 certs, the ACL check is made against the 1652certificate's distinguished name. This is something that looks like 1653@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1654made against the username, which depending on the SASL plugin, may 1655include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1656When the @option{acl} flag is set, the initial access list will be 1657empty, with a @code{deny} policy. Thus no one will be allowed to 1658use the VNC server until the ACLs have been loaded. This can be 1659achieved using the @code{acl} monitor command. 1660 1661@item lossy 1662 1663Enable lossy compression methods (gradient, JPEG, ...). If this 1664option is set, VNC client may receive lossy framebuffer updates 1665depending on its encoding settings. Enabling this option can save 1666a lot of bandwidth at the expense of quality. 1667 1668@item non-adaptive 1669 1670Disable adaptive encodings. Adaptive encodings are enabled by default. 1671An adaptive encoding will try to detect frequently updated screen regions, 1672and send updates in these regions using a lossy encoding (like JPEG). 1673This can be really helpful to save bandwidth when playing videos. Disabling 1674adaptive encodings restores the original static behavior of encodings 1675like Tight. 1676 1677@item share=[allow-exclusive|force-shared|ignore] 1678 1679Set display sharing policy. 'allow-exclusive' allows clients to ask 1680for exclusive access. As suggested by the rfb spec this is 1681implemented by dropping other connections. Connecting multiple 1682clients in parallel requires all clients asking for a shared session 1683(vncviewer: -shared switch). This is the default. 'force-shared' 1684disables exclusive client access. Useful for shared desktop sessions, 1685where you don't want someone forgetting specify -shared disconnect 1686everybody else. 'ignore' completely ignores the shared flag and 1687allows everybody connect unconditionally. Doesn't conform to the rfb 1688spec but is traditional QEMU behavior. 1689 1690@item key-delay-ms 1691 1692Set keyboard delay, for key down and key up events, in milliseconds. 1693Default is 10. Keyboards are low-bandwidth devices, so this slowdown 1694can help the device and guest to keep up and not lose events in case 1695events are arriving in bulk. Possible causes for the latter are flaky 1696network connections, or scripts for automated testing. 1697 1698@end table 1699ETEXI 1700 1701STEXI 1702@end table 1703ETEXI 1704ARCHHEADING(, QEMU_ARCH_I386) 1705 1706ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1707STEXI 1708@table @option 1709ETEXI 1710 1711DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1712 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1713 QEMU_ARCH_I386) 1714STEXI 1715@item -win2k-hack 1716@findex -win2k-hack 1717Use it when installing Windows 2000 to avoid a disk full bug. After 1718Windows 2000 is installed, you no longer need this option (this option 1719slows down the IDE transfers). 1720ETEXI 1721 1722DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1723 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1724 QEMU_ARCH_I386) 1725STEXI 1726@item -no-fd-bootchk 1727@findex -no-fd-bootchk 1728Disable boot signature checking for floppy disks in BIOS. May 1729be needed to boot from old floppy disks. 1730ETEXI 1731 1732DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1733 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1734STEXI 1735@item -no-acpi 1736@findex -no-acpi 1737Disable ACPI (Advanced Configuration and Power Interface) support. Use 1738it if your guest OS complains about ACPI problems (PC target machine 1739only). 1740ETEXI 1741 1742DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1743 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1744STEXI 1745@item -no-hpet 1746@findex -no-hpet 1747Disable HPET support. 1748ETEXI 1749 1750DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1751 "-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" 1752 " ACPI table description\n", QEMU_ARCH_I386) 1753STEXI 1754@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}]...] 1755@findex -acpitable 1756Add ACPI table with specified header fields and context from specified files. 1757For file=, take whole ACPI table from the specified files, including all 1758ACPI headers (possible overridden by other options). 1759For data=, only data 1760portion of the table is used, all header information is specified in the 1761command line. 1762If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1763fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1764to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1765spec. 1766ETEXI 1767 1768DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1769 "-smbios file=binary\n" 1770 " load SMBIOS entry from binary file\n" 1771 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1772 " [,uefi=on|off]\n" 1773 " specify SMBIOS type 0 fields\n" 1774 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1775 " [,uuid=uuid][,sku=str][,family=str]\n" 1776 " specify SMBIOS type 1 fields\n" 1777 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1778 " [,asset=str][,location=str]\n" 1779 " specify SMBIOS type 2 fields\n" 1780 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1781 " [,sku=str]\n" 1782 " specify SMBIOS type 3 fields\n" 1783 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1784 " [,asset=str][,part=str]\n" 1785 " specify SMBIOS type 4 fields\n" 1786 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1787 " [,asset=str][,part=str][,speed=%d]\n" 1788 " specify SMBIOS type 17 fields\n", 1789 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1790STEXI 1791@item -smbios file=@var{binary} 1792@findex -smbios 1793Load SMBIOS entry from binary file. 1794 1795@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1796Specify SMBIOS type 0 fields 1797 1798@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}] 1799Specify SMBIOS type 1 fields 1800 1801@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}] 1802Specify SMBIOS type 2 fields 1803 1804@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1805Specify SMBIOS type 3 fields 1806 1807@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1808Specify SMBIOS type 4 fields 1809 1810@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}] 1811Specify SMBIOS type 17 fields 1812ETEXI 1813 1814STEXI 1815@end table 1816ETEXI 1817DEFHEADING() 1818 1819DEFHEADING(Network options:) 1820STEXI 1821@table @option 1822ETEXI 1823 1824DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1825#ifdef CONFIG_SLIRP 1826 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 1827 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 1828 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1829 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n" 1830 " [,tftp=dir][,tftp-server-name=name][,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1831#ifndef _WIN32 1832 "[,smb=dir[,smbserver=addr]]\n" 1833#endif 1834 " configure a user mode network backend with ID 'str',\n" 1835 " its DHCP server and optional services\n" 1836#endif 1837#ifdef _WIN32 1838 "-netdev tap,id=str,ifname=name\n" 1839 " configure a host TAP network backend with ID 'str'\n" 1840#else 1841 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1842 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1843 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1844 " [,poll-us=n]\n" 1845 " configure a host TAP network backend with ID 'str'\n" 1846 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1847 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1848 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1849 " to deconfigure it\n" 1850 " use '[down]script=no' to disable script execution\n" 1851 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1852 " configure it\n" 1853 " use 'fd=h' to connect to an already opened TAP interface\n" 1854 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1855 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1856 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1857 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1858 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1859 " use vhost=on to enable experimental in kernel accelerator\n" 1860 " (only has effect for virtio guests which use MSIX)\n" 1861 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1862 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1863 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1864 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1865 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 1866 " spent on busy polling for vhost net\n" 1867 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1868 " configure a host TAP network backend with ID 'str' that is\n" 1869 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1870 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1871#endif 1872#ifdef __linux__ 1873 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1874 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1875 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1876 " [,rxcookie=rxcookie][,offset=offset]\n" 1877 " configure a network backend with ID 'str' connected to\n" 1878 " an Ethernet over L2TPv3 pseudowire.\n" 1879 " Linux kernel 3.3+ as well as most routers can talk\n" 1880 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1881 " VM to a router and even VM to Host. It is a nearly-universal\n" 1882 " standard (RFC3391). Note - this implementation uses static\n" 1883 " pre-configured tunnels (same as the Linux kernel).\n" 1884 " use 'src=' to specify source address\n" 1885 " use 'dst=' to specify destination address\n" 1886 " use 'udp=on' to specify udp encapsulation\n" 1887 " use 'srcport=' to specify source udp port\n" 1888 " use 'dstport=' to specify destination udp port\n" 1889 " use 'ipv6=on' to force v6\n" 1890 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1891 " well as a weak security measure\n" 1892 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1893 " use 'txcookie=0x012345678' to specify a txcookie\n" 1894 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1895 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1896 " use 'pincounter=on' to work around broken counter handling in peer\n" 1897 " use 'offset=X' to add an extra offset between header and data\n" 1898#endif 1899 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1900 " configure a network backend to connect to another network\n" 1901 " using a socket connection\n" 1902 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1903 " configure a network backend to connect to a multicast maddr and port\n" 1904 " use 'localaddr=addr' to specify the host address to send packets from\n" 1905 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1906 " configure a network backend to connect to another network\n" 1907 " using an UDP tunnel\n" 1908#ifdef CONFIG_VDE 1909 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1910 " configure a network backend to connect to port 'n' of a vde switch\n" 1911 " running on host and listening for incoming connections on 'socketpath'.\n" 1912 " Use group 'groupname' and mode 'octalmode' to change default\n" 1913 " ownership and permissions for communication port.\n" 1914#endif 1915#ifdef CONFIG_NETMAP 1916 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1917 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1918 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1919 " netmap device, defaults to '/dev/netmap')\n" 1920#endif 1921#ifdef CONFIG_POSIX 1922 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 1923 " configure a vhost-user network, backed by a chardev 'dev'\n" 1924#endif 1925 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n" 1926 " configure a hub port on the hub with ID 'n'\n", QEMU_ARCH_ALL) 1927DEF("nic", HAS_ARG, QEMU_OPTION_nic, 1928 "-nic [tap|bridge|" 1929#ifdef CONFIG_SLIRP 1930 "user|" 1931#endif 1932#ifdef __linux__ 1933 "l2tpv3|" 1934#endif 1935#ifdef CONFIG_VDE 1936 "vde|" 1937#endif 1938#ifdef CONFIG_NETMAP 1939 "netmap|" 1940#endif 1941#ifdef CONFIG_POSIX 1942 "vhost-user|" 1943#endif 1944 "socket][,option][,...][mac=macaddr]\n" 1945 " initialize an on-board / default host NIC (using MAC address\n" 1946 " macaddr) and connect it to the given host network backend\n" 1947 "-nic none use it alone to have zero network devices (the default is to\n" 1948 " provided a 'user' network connection)\n", 1949 QEMU_ARCH_ALL) 1950DEF("net", HAS_ARG, QEMU_OPTION_net, 1951 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1952 " configure or create an on-board (or machine default) NIC and\n" 1953 " connect it to hub 0 (please use -nic unless you need a hub)\n" 1954 "-net [" 1955#ifdef CONFIG_SLIRP 1956 "user|" 1957#endif 1958 "tap|" 1959 "bridge|" 1960#ifdef CONFIG_VDE 1961 "vde|" 1962#endif 1963#ifdef CONFIG_NETMAP 1964 "netmap|" 1965#endif 1966 "socket][,option][,option][,...]\n" 1967 " old way to initialize a host network interface\n" 1968 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 1969STEXI 1970@item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn] 1971@findex -nic 1972This option is a shortcut for configuring both the on-board (default) guest 1973NIC hardware and the host network backend in one go. The host backend options 1974are the same as with the corresponding @option{-netdev} options below. 1975The guest NIC model can be set with @option{model=@var{modelname}}. 1976Use @option{model=help} to list the available device types. 1977The hardware MAC address can be set with @option{mac=@var{macaddr}}. 1978 1979The following two example do exactly the same, to show how @option{-nic} can 1980be used to shorten the command line length (note that the e1000 is the default 1981on i386, so the @option{model=e1000} parameter could even be omitted here, too): 1982@example 1983qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32 1984qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32 1985@end example 1986 1987@item -nic none 1988Indicate that no network devices should be configured. It is used to override 1989the default configuration (default NIC with ``user'' host network backend) 1990which is activated if no other networking options are provided. 1991 1992@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1993@findex -netdev 1994Configure user mode host network backend which requires no administrator 1995privilege to run. Valid options are: 1996 1997@table @option 1998@item id=@var{id} 1999Assign symbolic name for use in monitor commands. 2000 2001@item ipv4=on|off and ipv6=on|off 2002Specify that either IPv4 or IPv6 must be enabled. If neither is specified 2003both protocols are enabled. 2004 2005@item net=@var{addr}[/@var{mask}] 2006Set IP network address the guest will see. Optionally specify the netmask, 2007either in the form a.b.c.d or as number of valid top-most bits. Default is 200810.0.2.0/24. 2009 2010@item host=@var{addr} 2011Specify the guest-visible address of the host. Default is the 2nd IP in the 2012guest network, i.e. x.x.x.2. 2013 2014@item ipv6-net=@var{addr}[/@var{int}] 2015Set IPv6 network address the guest will see (default is fec0::/64). The 2016network prefix is given in the usual hexadecimal IPv6 address 2017notation. The prefix size is optional, and is given as the number of 2018valid top-most bits (default is 64). 2019 2020@item ipv6-host=@var{addr} 2021Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 2022the guest network, i.e. xxxx::2. 2023 2024@item restrict=on|off 2025If this option is enabled, the guest will be isolated, i.e. it will not be 2026able to contact the host and no guest IP packets will be routed over the host 2027to the outside. This option does not affect any explicitly set forwarding rules. 2028 2029@item hostname=@var{name} 2030Specifies the client hostname reported by the built-in DHCP server. 2031 2032@item dhcpstart=@var{addr} 2033Specify the first of the 16 IPs the built-in DHCP server can assign. Default 2034is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 2035 2036@item dns=@var{addr} 2037Specify the guest-visible address of the virtual nameserver. The address must 2038be different from the host address. Default is the 3rd IP in the guest network, 2039i.e. x.x.x.3. 2040 2041@item ipv6-dns=@var{addr} 2042Specify the guest-visible address of the IPv6 virtual nameserver. The address 2043must be different from the host address. Default is the 3rd IP in the guest 2044network, i.e. xxxx::3. 2045 2046@item dnssearch=@var{domain} 2047Provides an entry for the domain-search list sent by the built-in 2048DHCP server. More than one domain suffix can be transmitted by specifying 2049this option multiple times. If supported, this will cause the guest to 2050automatically try to append the given domain suffix(es) in case a domain name 2051can not be resolved. 2052 2053Example: 2054@example 2055qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org 2056@end example 2057 2058@item domainname=@var{domain} 2059Specifies the client domain name reported by the built-in DHCP server. 2060 2061@item tftp=@var{dir} 2062When using the user mode network stack, activate a built-in TFTP 2063server. The files in @var{dir} will be exposed as the root of a TFTP server. 2064The TFTP client on the guest must be configured in binary mode (use the command 2065@code{bin} of the Unix TFTP client). 2066 2067@item tftp-server-name=@var{name} 2068In BOOTP reply, broadcast @var{name} as the "TFTP server name" (RFC2132 option 206966). This can be used to advise the guest to load boot files or configurations 2070from a different server than the host address. 2071 2072@item bootfile=@var{file} 2073When using the user mode network stack, broadcast @var{file} as the BOOTP 2074filename. In conjunction with @option{tftp}, this can be used to network boot 2075a guest from a local directory. 2076 2077Example (using pxelinux): 2078@example 2079qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \ 2080 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2081@end example 2082 2083@item smb=@var{dir}[,smbserver=@var{addr}] 2084When using the user mode network stack, activate a built-in SMB 2085server so that Windows OSes can access to the host files in @file{@var{dir}} 2086transparently. The IP address of the SMB server can be set to @var{addr}. By 2087default the 4th IP in the guest network is used, i.e. x.x.x.4. 2088 2089In the guest Windows OS, the line: 2090@example 209110.0.2.4 smbserver 2092@end example 2093must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2094or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2095 2096Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2097 2098Note that a SAMBA server must be installed on the host OS. 2099 2100@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2101Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2102the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2103@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2104given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2105be bound to a specific host interface. If no connection type is set, TCP is 2106used. This option can be given multiple times. 2107 2108For example, to redirect host X11 connection from screen 1 to guest 2109screen 0, use the following: 2110 2111@example 2112# on the host 2113qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000 2114# this host xterm should open in the guest X11 server 2115xterm -display :1 2116@end example 2117 2118To redirect telnet connections from host port 5555 to telnet port on 2119the guest, use the following: 2120 2121@example 2122# on the host 2123qemu-system-i386 -nic user,hostfwd=tcp::5555-:23 2124telnet localhost 5555 2125@end example 2126 2127Then when you use on the host @code{telnet localhost 5555}, you 2128connect to the guest telnet server. 2129 2130@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2131@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2132Forward guest TCP connections to the IP address @var{server} on port @var{port} 2133to the character device @var{dev} or to a program executed by @var{cmd:command} 2134which gets spawned for each connection. This option can be given multiple times. 2135 2136You can either use a chardev directly and have that one used throughout QEMU's 2137lifetime, like in the following example: 2138 2139@example 2140# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2141# the guest accesses it 2142qemu-system-i386 -nic user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 2143@end example 2144 2145Or you can execute a command on every TCP connection established by the guest, 2146so that QEMU behaves similar to an inetd process for that virtual server: 2147 2148@example 2149# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2150# and connect the TCP stream to its stdin/stdout 2151qemu-system-i386 -nic 'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2152@end example 2153 2154@end table 2155 2156@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2157Configure a host TAP network backend with ID @var{id}. 2158 2159Use the network script @var{file} to configure it and the network script 2160@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2161automatically provides one. The default network configure script is 2162@file{/etc/qemu-ifup} and the default network deconfigure script is 2163@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2164to disable script execution. 2165 2166If running QEMU as an unprivileged user, use the network helper 2167@var{helper} to configure the TAP interface and attach it to the bridge. 2168The default network helper executable is @file{/path/to/qemu-bridge-helper} 2169and the default bridge device is @file{br0}. 2170 2171@option{fd}=@var{h} can be used to specify the handle of an already 2172opened host TAP interface. 2173 2174Examples: 2175 2176@example 2177#launch a QEMU instance with the default network script 2178qemu-system-i386 linux.img -nic tap 2179@end example 2180 2181@example 2182#launch a QEMU instance with two NICs, each one connected 2183#to a TAP device 2184qemu-system-i386 linux.img \ 2185 -netdev tap,id=nd0,ifname=tap0 -device e1000,netdev=nd0 \ 2186 -netdev tap,id=nd1,ifname=tap1 -device rtl8139,netdev=nd1 2187@end example 2188 2189@example 2190#launch a QEMU instance with the default network helper to 2191#connect a TAP device to bridge br0 2192qemu-system-i386 linux.img -device virtio-net-pci,netdev=n1 \ 2193 -netdev tap,id=n1,"helper=/path/to/qemu-bridge-helper" 2194@end example 2195 2196@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2197Connect a host TAP network interface to a host bridge device. 2198 2199Use the network helper @var{helper} to configure the TAP interface and 2200attach it to the bridge. The default network helper executable is 2201@file{/path/to/qemu-bridge-helper} and the default bridge 2202device is @file{br0}. 2203 2204Examples: 2205 2206@example 2207#launch a QEMU instance with the default network helper to 2208#connect a TAP device to bridge br0 2209qemu-system-i386 linux.img -netdev bridge,id=n1 -device virtio-net,netdev=n1 2210@end example 2211 2212@example 2213#launch a QEMU instance with the default network helper to 2214#connect a TAP device to bridge qemubr0 2215qemu-system-i386 linux.img -netdev bridge,br=qemubr0,id=n1 -device virtio-net,netdev=n1 2216@end example 2217 2218@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2219 2220This host network backend can be used to connect the guest's network to 2221another QEMU virtual machine using a TCP socket connection. If @option{listen} 2222is specified, QEMU waits for incoming connections on @var{port} 2223(@var{host} is optional). @option{connect} is used to connect to 2224another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2225specifies an already opened TCP socket. 2226 2227Example: 2228@example 2229# launch a first QEMU instance 2230qemu-system-i386 linux.img \ 2231 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2232 -netdev socket,id=n1,listen=:1234 2233# connect the network of this instance to the network of the first instance 2234qemu-system-i386 linux.img \ 2235 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2236 -netdev socket,id=n2,connect=127.0.0.1:1234 2237@end example 2238 2239@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2240 2241Configure a socket host network backend to share the guest's network traffic 2242with another QEMU virtual machines using a UDP multicast socket, effectively 2243making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. 2244NOTES: 2245@enumerate 2246@item 2247Several QEMU can be running on different hosts and share same bus (assuming 2248correct multicast setup for these hosts). 2249@item 2250mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2251@url{http://user-mode-linux.sf.net}. 2252@item 2253Use @option{fd=h} to specify an already opened UDP multicast socket. 2254@end enumerate 2255 2256Example: 2257@example 2258# launch one QEMU instance 2259qemu-system-i386 linux.img \ 2260 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2261 -netdev socket,id=n1,mcast=230.0.0.1:1234 2262# launch another QEMU instance on same "bus" 2263qemu-system-i386 linux.img \ 2264 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \ 2265 -netdev socket,id=n2,mcast=230.0.0.1:1234 2266# launch yet another QEMU instance on same "bus" 2267qemu-system-i386 linux.img \ 2268 -device e1000,netdev=n3,mac=52:54:00:12:34:58 \ 2269 -netdev socket,id=n3,mcast=230.0.0.1:1234 2270@end example 2271 2272Example (User Mode Linux compat.): 2273@example 2274# launch QEMU instance (note mcast address selected is UML's default) 2275qemu-system-i386 linux.img \ 2276 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \ 2277 -netdev socket,id=n1,mcast=239.192.168.1:1102 2278# launch UML 2279/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2280@end example 2281 2282Example (send packets from host's 1.2.3.4): 2283@example 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,localaddr=1.2.3.4 2287@end example 2288 2289@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}] 2290Configure a L2TPv3 pseudowire host network backend. L2TPv3 (RFC3391) is a 2291popular protocol to transport Ethernet (and other Layer 2) data frames between 2292two systems. It is present in routers, firewalls and the Linux kernel 2293(from version 3.3 onwards). 2294 2295This transport allows a VM to communicate to another VM, router or firewall directly. 2296 2297@table @option 2298@item src=@var{srcaddr} 2299 source address (mandatory) 2300@item dst=@var{dstaddr} 2301 destination address (mandatory) 2302@item udp 2303 select udp encapsulation (default is ip). 2304@item srcport=@var{srcport} 2305 source udp port. 2306@item dstport=@var{dstport} 2307 destination udp port. 2308@item ipv6 2309 force v6, otherwise defaults to v4. 2310@item rxcookie=@var{rxcookie} 2311@itemx txcookie=@var{txcookie} 2312 Cookies are a weak form of security in the l2tpv3 specification. 2313Their function is mostly to prevent misconfiguration. By default they are 32 2314bit. 2315@item cookie64 2316 Set cookie size to 64 bit instead of the default 32 2317@item counter=off 2318 Force a 'cut-down' L2TPv3 with no counter as in 2319draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2320@item pincounter=on 2321 Work around broken counter handling in peer. This may also help on 2322networks which have packet reorder. 2323@item offset=@var{offset} 2324 Add an extra offset between header and data 2325@end table 2326 2327For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2328on the remote Linux host 1.2.3.4: 2329@example 2330# Setup tunnel on linux host using raw ip as encapsulation 2331# on 1.2.3.4 2332ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2333 encap udp udp_sport 16384 udp_dport 16384 2334ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2335 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2336ifconfig vmtunnel0 mtu 1500 2337ifconfig vmtunnel0 up 2338brctl addif br-lan vmtunnel0 2339 2340 2341# on 4.3.2.1 2342# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2343 2344qemu-system-i386 linux.img -device e1000,netdev=n1 \ 2345 -netdev l2tpv3,id=n1,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2346 2347@end example 2348 2349@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2350Configure VDE backend to connect to PORT @var{n} of a vde switch running on host and 2351listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2352and MODE @var{octalmode} to change default ownership and permissions for 2353communication port. This option is only available if QEMU has been compiled 2354with vde support enabled. 2355 2356Example: 2357@example 2358# launch vde switch 2359vde_switch -F -sock /tmp/myswitch 2360# launch QEMU instance 2361qemu-system-i386 linux.img -nic vde,sock=/tmp/myswitch 2362@end example 2363 2364@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2365 2366Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2367be a unix domain socket backed one. The vhost-user uses a specifically defined 2368protocol to pass vhost ioctl replacement messages to an application on the other 2369end of the socket. On non-MSIX guests, the feature can be forced with 2370@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2371be created for multiqueue vhost-user. 2372 2373Example: 2374@example 2375qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2376 -numa node,memdev=mem \ 2377 -chardev socket,id=chr0,path=/path/to/socket \ 2378 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2379 -device virtio-net-pci,netdev=net0 2380@end example 2381 2382@item -netdev hubport,id=@var{id},hubid=@var{hubid}[,netdev=@var{nd}] 2383 2384Create a hub port on the emulated hub with ID @var{hubid}. 2385 2386The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a 2387single netdev. Alternatively, you can also connect the hubport to another 2388netdev with ID @var{nd} by using the @option{netdev=@var{nd}} option. 2389 2390@item -net nic[,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2391@findex -net 2392Legacy option to configure or create an on-board (or machine default) Network 2393Interface Card(NIC) and connect it either to the emulated hub with ID 0 (i.e. 2394the default hub), or to the netdev @var{nd}. 2395The NIC is an e1000 by default on the PC target. Optionally, the MAC address 2396can be changed to @var{mac}, the device address set to @var{addr} (PCI cards 2397only), and a @var{name} can be assigned for use in monitor commands. 2398Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2399that the card should have; this option currently only affects virtio cards; set 2400@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2401NIC is created. QEMU can emulate several different models of network card. 2402Use @code{-net nic,model=help} for a list of available devices for your target. 2403 2404@item -net user|tap|bridge|socket|l2tpv3|vde[,...][,name=@var{name}] 2405Configure a host network backend (with the options corresponding to the same 2406@option{-netdev} option) and connect it to the emulated hub 0 (the default 2407hub). Use @var{name} to specify the name of the hub port. 2408ETEXI 2409 2410STEXI 2411@end table 2412ETEXI 2413DEFHEADING() 2414 2415DEFHEADING(Character device options:) 2416 2417DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2418 "-chardev help\n" 2419 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2420 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2421 " [,server][,nowait][,telnet][,websocket][,reconnect=seconds][,mux=on|off]\n" 2422 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2423 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,websocket][,reconnect=seconds]\n" 2424 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2425 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2426 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2427 " [,logfile=PATH][,logappend=on|off]\n" 2428 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2429 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2430 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2431 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2432 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2433 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2434#ifdef _WIN32 2435 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2436 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2437#else 2438 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2439 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2440#endif 2441#ifdef CONFIG_BRLAPI 2442 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2443#endif 2444#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2445 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2446 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2447 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2448#endif 2449#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2450 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2451 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2452#endif 2453#if defined(CONFIG_SPICE) 2454 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2455 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2456#endif 2457 , QEMU_ARCH_ALL 2458) 2459 2460STEXI 2461 2462The general form of a character device option is: 2463@table @option 2464@item -chardev @var{backend},id=@var{id}[,mux=on|off][,@var{options}] 2465@findex -chardev 2466Backend is one of: 2467@option{null}, 2468@option{socket}, 2469@option{udp}, 2470@option{msmouse}, 2471@option{vc}, 2472@option{ringbuf}, 2473@option{file}, 2474@option{pipe}, 2475@option{console}, 2476@option{serial}, 2477@option{pty}, 2478@option{stdio}, 2479@option{braille}, 2480@option{tty}, 2481@option{parallel}, 2482@option{parport}, 2483@option{spicevmc}, 2484@option{spiceport}. 2485The specific backend will determine the applicable options. 2486 2487Use @code{-chardev help} to print all available chardev backend types. 2488 2489All devices must have an id, which can be any string up to 127 characters long. 2490It is used to uniquely identify this device in other command line directives. 2491 2492A character device may be used in multiplexing mode by multiple front-ends. 2493Specify @option{mux=on} to enable this mode. 2494A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2495backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2496If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2497create a multiplexer with your specified ID, and you can then configure multiple 2498front ends to use that chardev ID for their input/output. Up to four different 2499front ends can be connected to a single multiplexed chardev. (Without 2500multiplexing enabled, a chardev can only be used by a single front end.) 2501For instance you could use this to allow a single stdio chardev to be used by 2502two serial ports and the QEMU monitor: 2503 2504@example 2505-chardev stdio,mux=on,id=char0 \ 2506-mon chardev=char0,mode=readline \ 2507-serial chardev:char0 \ 2508-serial chardev:char0 2509@end example 2510 2511You can have more than one multiplexer in a system configuration; for instance 2512you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2513multiplexed between the QEMU monitor and a parallel port: 2514 2515@example 2516-chardev stdio,mux=on,id=char0 \ 2517-mon chardev=char0,mode=readline \ 2518-parallel chardev:char0 \ 2519-chardev tcp,...,mux=on,id=char1 \ 2520-serial chardev:char1 \ 2521-serial chardev:char1 2522@end example 2523 2524When you're using a multiplexed character device, some escape sequences are 2525interpreted in the input. @xref{mux_keys, Keys in the character backend 2526multiplexer}. 2527 2528Note that some other command line options may implicitly create multiplexed 2529character backends; for instance @option{-serial mon:stdio} creates a 2530multiplexed stdio backend connected to the serial port and the QEMU monitor, 2531and @option{-nographic} also multiplexes the console and the monitor to 2532stdio. 2533 2534There is currently no support for multiplexing in the other direction 2535(where a single QEMU front end takes input and output from multiple chardevs). 2536 2537Every backend supports the @option{logfile} option, which supplies the path 2538to a file to record all data transmitted via the backend. The @option{logappend} 2539option controls whether the log file will be truncated or appended to when 2540opened. 2541 2542@end table 2543 2544The available backends are: 2545 2546@table @option 2547@item -chardev null,id=@var{id} 2548A void device. This device will not emit any data, and will drop any data it 2549receives. The null backend does not take any options. 2550 2551@item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,websocket][,reconnect=@var{seconds}][,tls-creds=@var{id}] 2552 2553Create a two-way stream socket, which can be either a TCP or a unix socket. A 2554unix socket will be created if @option{path} is specified. Behaviour is 2555undefined if TCP options are specified for a unix socket. 2556 2557@option{server} specifies that the socket shall be a listening socket. 2558 2559@option{nowait} specifies that QEMU should not block waiting for a client to 2560connect to a listening socket. 2561 2562@option{telnet} specifies that traffic on the socket should interpret telnet 2563escape sequences. 2564 2565@option{websocket} specifies that the socket uses WebSocket protocol for 2566communication. 2567 2568@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2569the remote end goes away. qemu will delay this many seconds and then attempt 2570to reconnect. Zero disables reconnecting, and is the default. 2571 2572@option{tls-creds} requests enablement of the TLS protocol for encryption, 2573and specifies the id of the TLS credentials to use for the handshake. The 2574credentials must be previously created with the @option{-object tls-creds} 2575argument. 2576 2577TCP and unix socket options are given below: 2578 2579@table @option 2580 2581@item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay] 2582 2583@option{host} for a listening socket specifies the local address to be bound. 2584For a connecting socket species the remote host to connect to. @option{host} is 2585optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2586 2587@option{port} for a listening socket specifies the local port to be bound. For a 2588connecting socket specifies the port on the remote host to connect to. 2589@option{port} can be given as either a port number or a service name. 2590@option{port} is required. 2591 2592@option{to} is only relevant to listening sockets. If it is specified, and 2593@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2594to and including @option{to} until it succeeds. @option{to} must be specified 2595as a port number. 2596 2597@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2598If neither is specified the socket may use either protocol. 2599 2600@option{nodelay} disables the Nagle algorithm. 2601 2602@item unix options: path=@var{path} 2603 2604@option{path} specifies the local path of the unix socket. @option{path} is 2605required. 2606 2607@end table 2608 2609@item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6] 2610 2611Sends all traffic from the guest to a remote host over UDP. 2612 2613@option{host} specifies the remote host to connect to. If not specified it 2614defaults to @code{localhost}. 2615 2616@option{port} specifies the port on the remote host to connect to. @option{port} 2617is required. 2618 2619@option{localaddr} specifies the local address to bind to. If not specified it 2620defaults to @code{0.0.0.0}. 2621 2622@option{localport} specifies the local port to bind to. If not specified any 2623available local port will be used. 2624 2625@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2626If neither is specified the device may use either protocol. 2627 2628@item -chardev msmouse,id=@var{id} 2629 2630Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2631take any options. 2632 2633@item -chardev vc,id=@var{id}[[,width=@var{width}][,height=@var{height}]][[,cols=@var{cols}][,rows=@var{rows}]] 2634 2635Connect to a QEMU text console. @option{vc} may optionally be given a specific 2636size. 2637 2638@option{width} and @option{height} specify the width and height respectively of 2639the console, in pixels. 2640 2641@option{cols} and @option{rows} specify that the console be sized to fit a text 2642console with the given dimensions. 2643 2644@item -chardev ringbuf,id=@var{id}[,size=@var{size}] 2645 2646Create a ring buffer with fixed size @option{size}. 2647@var{size} must be a power of two and defaults to @code{64K}. 2648 2649@item -chardev file,id=@var{id},path=@var{path} 2650 2651Log all traffic received from the guest to a file. 2652 2653@option{path} specifies the path of the file to be opened. This file will be 2654created if it does not already exist, and overwritten if it does. @option{path} 2655is required. 2656 2657@item -chardev pipe,id=@var{id},path=@var{path} 2658 2659Create a two-way connection to the guest. The behaviour differs slightly between 2660Windows hosts and other hosts: 2661 2662On Windows, a single duplex pipe will be created at 2663@file{\\.pipe\@option{path}}. 2664 2665On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2666@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2667received by the guest. Data written by the guest can be read from 2668@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2669be present. 2670 2671@option{path} forms part of the pipe path as described above. @option{path} is 2672required. 2673 2674@item -chardev console,id=@var{id} 2675 2676Send traffic from the guest to QEMU's standard output. @option{console} does not 2677take any options. 2678 2679@option{console} is only available on Windows hosts. 2680 2681@item -chardev serial,id=@var{id},path=@option{path} 2682 2683Send traffic from the guest to a serial device on the host. 2684 2685On Unix hosts serial will actually accept any tty device, 2686not only serial lines. 2687 2688@option{path} specifies the name of the serial device to open. 2689 2690@item -chardev pty,id=@var{id} 2691 2692Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2693not take any options. 2694 2695@option{pty} is not available on Windows hosts. 2696 2697@item -chardev stdio,id=@var{id}[,signal=on|off] 2698Connect to standard input and standard output of the QEMU process. 2699 2700@option{signal} controls if signals are enabled on the terminal, that includes 2701exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2702default, use @option{signal=off} to disable it. 2703 2704@item -chardev braille,id=@var{id} 2705 2706Connect to a local BrlAPI server. @option{braille} does not take any options. 2707 2708@item -chardev tty,id=@var{id},path=@var{path} 2709 2710@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2711DragonFlyBSD hosts. It is an alias for @option{serial}. 2712 2713@option{path} specifies the path to the tty. @option{path} is required. 2714 2715@item -chardev parallel,id=@var{id},path=@var{path} 2716@itemx -chardev parport,id=@var{id},path=@var{path} 2717 2718@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2719 2720Connect to a local parallel port. 2721 2722@option{path} specifies the path to the parallel port device. @option{path} is 2723required. 2724 2725@item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name} 2726 2727@option{spicevmc} is only available when spice support is built in. 2728 2729@option{debug} debug level for spicevmc 2730 2731@option{name} name of spice channel to connect to 2732 2733Connect to a spice virtual machine channel, such as vdiport. 2734 2735@item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name} 2736 2737@option{spiceport} is only available when spice support is built in. 2738 2739@option{debug} debug level for spicevmc 2740 2741@option{name} name of spice port to connect to 2742 2743Connect to a spice port, allowing a Spice client to handle the traffic 2744identified by a name (preferably a fqdn). 2745ETEXI 2746 2747STEXI 2748@end table 2749ETEXI 2750DEFHEADING() 2751 2752DEFHEADING(Bluetooth(R) options:) 2753STEXI 2754@table @option 2755ETEXI 2756 2757DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2758 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2759 "-bt hci,host[:id]\n" \ 2760 " use host's HCI with the given name\n" \ 2761 "-bt hci[,vlan=n]\n" \ 2762 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2763 "-bt vhci[,vlan=n]\n" \ 2764 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2765 "-bt device:dev[,vlan=n]\n" \ 2766 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2767 QEMU_ARCH_ALL) 2768STEXI 2769@item -bt hci[...] 2770@findex -bt 2771Defines the function of the corresponding Bluetooth HCI. -bt options 2772are matched with the HCIs present in the chosen machine type. For 2773example when emulating a machine with only one HCI built into it, only 2774the first @code{-bt hci[...]} option is valid and defines the HCI's 2775logic. The Transport Layer is decided by the machine type. Currently 2776the machines @code{n800} and @code{n810} have one HCI and all other 2777machines have none. 2778 2779Note: This option and the whole bluetooth subsystem is considered as deprecated. 2780If you still use it, please send a mail to @email{qemu-devel@@nongnu.org} where 2781you describe your usecase. 2782 2783@anchor{bt-hcis} 2784The following three types are recognized: 2785 2786@table @option 2787@item -bt hci,null 2788(default) The corresponding Bluetooth HCI assumes no internal logic 2789and will not respond to any HCI commands or emit events. 2790 2791@item -bt hci,host[:@var{id}] 2792(@code{bluez} only) The corresponding HCI passes commands / events 2793to / from the physical HCI identified by the name @var{id} (default: 2794@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2795capable systems like Linux. 2796 2797@item -bt hci[,vlan=@var{n}] 2798Add a virtual, standard HCI that will participate in the Bluetooth 2799scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2800VLANs, devices inside a bluetooth network @var{n} can only communicate 2801with other devices in the same network (scatternet). 2802@end table 2803 2804@item -bt vhci[,vlan=@var{n}] 2805(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2806to the host bluetooth stack instead of to the emulated target. This 2807allows the host and target machines to participate in a common scatternet 2808and communicate. Requires the Linux @code{vhci} driver installed. Can 2809be used as following: 2810 2811@example 2812qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2813@end example 2814 2815@item -bt device:@var{dev}[,vlan=@var{n}] 2816Emulate a bluetooth device @var{dev} and place it in network @var{n} 2817(default @code{0}). QEMU can only emulate one type of bluetooth devices 2818currently: 2819 2820@table @option 2821@item keyboard 2822Virtual wireless keyboard implementing the HIDP bluetooth profile. 2823@end table 2824ETEXI 2825 2826STEXI 2827@end table 2828ETEXI 2829DEFHEADING() 2830 2831#ifdef CONFIG_TPM 2832DEFHEADING(TPM device options:) 2833 2834DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2835 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2836 " use path to provide path to a character device; default is /dev/tpm0\n" 2837 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2838 " not provided it will be searched for in /sys/class/misc/tpm?/device\n" 2839 "-tpmdev emulator,id=id,chardev=dev\n" 2840 " configure the TPM device using chardev backend\n", 2841 QEMU_ARCH_ALL) 2842STEXI 2843 2844The general form of a TPM device option is: 2845@table @option 2846 2847@item -tpmdev @var{backend},id=@var{id}[,@var{options}] 2848@findex -tpmdev 2849 2850The specific backend type will determine the applicable options. 2851The @code{-tpmdev} option creates the TPM backend and requires a 2852@code{-device} option that specifies the TPM frontend interface model. 2853 2854Use @code{-tpmdev help} to print all available TPM backend types. 2855 2856@end table 2857 2858The available backends are: 2859 2860@table @option 2861 2862@item -tpmdev passthrough,id=@var{id},path=@var{path},cancel-path=@var{cancel-path} 2863 2864(Linux-host only) Enable access to the host's TPM using the passthrough 2865driver. 2866 2867@option{path} specifies the path to the host's TPM device, i.e., on 2868a Linux host this would be @code{/dev/tpm0}. 2869@option{path} is optional and by default @code{/dev/tpm0} is used. 2870 2871@option{cancel-path} specifies the path to the host TPM device's sysfs 2872entry allowing for cancellation of an ongoing TPM command. 2873@option{cancel-path} is optional and by default QEMU will search for the 2874sysfs entry to use. 2875 2876Some notes about using the host's TPM with the passthrough driver: 2877 2878The TPM device accessed by the passthrough driver must not be 2879used by any other application on the host. 2880 2881Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2882the VM's firmware (BIOS/UEFI) will not be able to initialize the 2883TPM again and may therefore not show a TPM-specific menu that would 2884otherwise allow the user to configure the TPM, e.g., allow the user to 2885enable/disable or activate/deactivate the TPM. 2886Further, if TPM ownership is released from within a VM then the host's TPM 2887will get disabled and deactivated. To enable and activate the 2888TPM again afterwards, the host has to be rebooted and the user is 2889required to enter the firmware's menu to enable and activate the TPM. 2890If the TPM is left disabled and/or deactivated most TPM commands will fail. 2891 2892To create a passthrough TPM use the following two options: 2893@example 2894-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2895@end example 2896Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2897@code{tpmdev=tpm0} in the device option. 2898 2899@item -tpmdev emulator,id=@var{id},chardev=@var{dev} 2900 2901(Linux-host only) Enable access to a TPM emulator using Unix domain socket based 2902chardev backend. 2903 2904@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server. 2905 2906To create a TPM emulator backend device with chardev socket backend: 2907@example 2908 2909-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0 2910 2911@end example 2912 2913ETEXI 2914 2915STEXI 2916@end table 2917ETEXI 2918DEFHEADING() 2919 2920#endif 2921 2922DEFHEADING(Linux/Multiboot boot specific:) 2923STEXI 2924 2925When using these options, you can use a given Linux or Multiboot 2926kernel without installing it in the disk image. It can be useful 2927for easier testing of various kernels. 2928 2929@table @option 2930ETEXI 2931 2932DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2933 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2934STEXI 2935@item -kernel @var{bzImage} 2936@findex -kernel 2937Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2938or in multiboot format. 2939ETEXI 2940 2941DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2942 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2943STEXI 2944@item -append @var{cmdline} 2945@findex -append 2946Use @var{cmdline} as kernel command line 2947ETEXI 2948 2949DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2950 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2951STEXI 2952@item -initrd @var{file} 2953@findex -initrd 2954Use @var{file} as initial ram disk. 2955 2956@item -initrd "@var{file1} arg=foo,@var{file2}" 2957 2958This syntax is only available with multiboot. 2959 2960Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2961first module. 2962ETEXI 2963 2964DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2965 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2966STEXI 2967@item -dtb @var{file} 2968@findex -dtb 2969Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2970on boot. 2971ETEXI 2972 2973STEXI 2974@end table 2975ETEXI 2976DEFHEADING() 2977 2978DEFHEADING(Debug/Expert options:) 2979STEXI 2980@table @option 2981ETEXI 2982 2983DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 2984 "-fw_cfg [name=]<name>,file=<file>\n" 2985 " add named fw_cfg entry with contents from file\n" 2986 "-fw_cfg [name=]<name>,string=<str>\n" 2987 " add named fw_cfg entry with contents from string\n", 2988 QEMU_ARCH_ALL) 2989STEXI 2990 2991@item -fw_cfg [name=]@var{name},file=@var{file} 2992@findex -fw_cfg 2993Add named fw_cfg entry with contents from file @var{file}. 2994 2995@item -fw_cfg [name=]@var{name},string=@var{str} 2996Add named fw_cfg entry with contents from string @var{str}. 2997 2998The terminating NUL character of the contents of @var{str} will not be 2999included as part of the fw_cfg item data. To insert contents with 3000embedded NUL characters, you have to use the @var{file} parameter. 3001 3002The fw_cfg entries are passed by QEMU through to the guest. 3003 3004Example: 3005@example 3006 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 3007@end example 3008creates an fw_cfg entry named opt/com.mycompany/blob with contents 3009from ./my_blob.bin. 3010 3011ETEXI 3012 3013DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 3014 "-serial dev redirect the serial port to char device 'dev'\n", 3015 QEMU_ARCH_ALL) 3016STEXI 3017@item -serial @var{dev} 3018@findex -serial 3019Redirect the virtual serial port to host character device 3020@var{dev}. The default device is @code{vc} in graphical mode and 3021@code{stdio} in non graphical mode. 3022 3023This option can be used several times to simulate up to 4 serial 3024ports. 3025 3026Use @code{-serial none} to disable all serial ports. 3027 3028Available character devices are: 3029@table @option 3030@item vc[:@var{W}x@var{H}] 3031Virtual console. Optionally, a width and height can be given in pixel with 3032@example 3033vc:800x600 3034@end example 3035It is also possible to specify width or height in characters: 3036@example 3037vc:80Cx24C 3038@end example 3039@item pty 3040[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3041@item none 3042No device is allocated. 3043@item null 3044void device 3045@item chardev:@var{id} 3046Use a named character device defined with the @code{-chardev} option. 3047@item /dev/XXX 3048[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3049parameters are set according to the emulated ones. 3050@item /dev/parport@var{N} 3051[Linux only, parallel port only] Use host parallel port 3052@var{N}. Currently SPP and EPP parallel port features can be used. 3053@item file:@var{filename} 3054Write output to @var{filename}. No character can be read. 3055@item stdio 3056[Unix only] standard input/output 3057@item pipe:@var{filename} 3058name pipe @var{filename} 3059@item COM@var{n} 3060[Windows only] Use host serial port @var{n} 3061@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3062This implements UDP Net Console. 3063When @var{remote_host} or @var{src_ip} are not specified 3064they default to @code{0.0.0.0}. 3065When not using a specified @var{src_port} a random port is automatically chosen. 3066 3067If you just want a simple readonly console you can use @code{netcat} or 3068@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3069@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3070will appear in the netconsole session. 3071 3072If you plan to send characters back via netconsole or you want to stop 3073and start QEMU a lot of times, you should have QEMU use the same 3074source port each time by using something like @code{-serial 3075udp::4555@@:4556} to QEMU. Another approach is to use a patched 3076version of netcat which can listen to a TCP port and send and receive 3077characters via udp. If you have a patched version of netcat which 3078activates telnet remote echo and single char transfer, then you can 3079use the following options to set up a netcat redirector to allow 3080telnet on port 5555 to access the QEMU port. 3081@table @code 3082@item QEMU Options: 3083-serial udp::4555@@:4556 3084@item netcat options: 3085-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3086@item telnet options: 3087localhost 5555 3088@end table 3089 3090@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3091The TCP Net Console has two modes of operation. It can send the serial 3092I/O to a location or wait for a connection from a location. By default 3093the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3094the @var{server} option QEMU will wait for a client socket application 3095to connect to the port before continuing, unless the @code{nowait} 3096option was specified. The @code{nodelay} option disables the Nagle buffering 3097algorithm. The @code{reconnect} option only applies if @var{noserver} is 3098set, if the connection goes down it will attempt to reconnect at the 3099given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3100one TCP connection at a time is accepted. You can use @code{telnet} to 3101connect to the corresponding character device. 3102@table @code 3103@item Example to send tcp console to 192.168.0.2 port 4444 3104-serial tcp:192.168.0.2:4444 3105@item Example to listen and wait on port 4444 for connection 3106-serial tcp::4444,server 3107@item Example to not wait and listen on ip 192.168.0.100 port 4444 3108-serial tcp:192.168.0.100:4444,server,nowait 3109@end table 3110 3111@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3112The telnet protocol is used instead of raw tcp sockets. The options 3113work the same as if you had specified @code{-serial tcp}. The 3114difference is that the port acts like a telnet server or client using 3115telnet option negotiation. This will also allow you to send the 3116MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3117sequence. Typically in unix telnet you do it with Control-] and then 3118type "send break" followed by pressing the enter key. 3119 3120@item websocket:@var{host}:@var{port},server[,nowait][,nodelay] 3121The WebSocket protocol is used instead of raw tcp socket. The port acts as 3122a WebSocket server. Client mode is not supported. 3123 3124@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3125A unix domain socket is used instead of a tcp socket. The option works the 3126same as if you had specified @code{-serial tcp} except the unix domain socket 3127@var{path} is used for connections. 3128 3129@item mon:@var{dev_string} 3130This is a special option to allow the monitor to be multiplexed onto 3131another serial port. The monitor is accessed with key sequence of 3132@key{Control-a} and then pressing @key{c}. 3133@var{dev_string} should be any one of the serial devices specified 3134above. An example to multiplex the monitor onto a telnet server 3135listening on port 4444 would be: 3136@table @code 3137@item -serial mon:telnet::4444,server,nowait 3138@end table 3139When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3140QEMU any more but will be passed to the guest instead. 3141 3142@item braille 3143Braille device. This will use BrlAPI to display the braille output on a real 3144or fake device. 3145 3146@item msmouse 3147Three button serial mouse. Configure the guest to use Microsoft protocol. 3148@end table 3149ETEXI 3150 3151DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3152 "-parallel dev redirect the parallel port to char device 'dev'\n", 3153 QEMU_ARCH_ALL) 3154STEXI 3155@item -parallel @var{dev} 3156@findex -parallel 3157Redirect the virtual parallel port to host device @var{dev} (same 3158devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3159be used to use hardware devices connected on the corresponding host 3160parallel port. 3161 3162This option can be used several times to simulate up to 3 parallel 3163ports. 3164 3165Use @code{-parallel none} to disable all parallel ports. 3166ETEXI 3167 3168DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3169 "-monitor dev redirect the monitor to char device 'dev'\n", 3170 QEMU_ARCH_ALL) 3171STEXI 3172@item -monitor @var{dev} 3173@findex -monitor 3174Redirect the monitor to host device @var{dev} (same devices as the 3175serial port). 3176The default device is @code{vc} in graphical mode and @code{stdio} in 3177non graphical mode. 3178Use @code{-monitor none} to disable the default monitor. 3179ETEXI 3180DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3181 "-qmp dev like -monitor but opens in 'control' mode\n", 3182 QEMU_ARCH_ALL) 3183STEXI 3184@item -qmp @var{dev} 3185@findex -qmp 3186Like -monitor but opens in 'control' mode. 3187ETEXI 3188DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3189 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3190 QEMU_ARCH_ALL) 3191STEXI 3192@item -qmp-pretty @var{dev} 3193@findex -qmp-pretty 3194Like -qmp but uses pretty JSON formatting. 3195ETEXI 3196 3197DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3198 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL) 3199STEXI 3200@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]] 3201@findex -mon 3202Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing 3203easing human reading and debugging. 3204ETEXI 3205 3206DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3207 "-debugcon dev redirect the debug console to char device 'dev'\n", 3208 QEMU_ARCH_ALL) 3209STEXI 3210@item -debugcon @var{dev} 3211@findex -debugcon 3212Redirect the debug console to host device @var{dev} (same devices as the 3213serial port). The debug console is an I/O port which is typically port 32140xe9; writing to that I/O port sends output to this device. 3215The default device is @code{vc} in graphical mode and @code{stdio} in 3216non graphical mode. 3217ETEXI 3218 3219DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3220 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3221STEXI 3222@item -pidfile @var{file} 3223@findex -pidfile 3224Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3225from a script. 3226ETEXI 3227 3228DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3229 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3230STEXI 3231@item -singlestep 3232@findex -singlestep 3233Run the emulation in single step mode. 3234ETEXI 3235 3236DEF("preconfig", 0, QEMU_OPTION_preconfig, \ 3237 "--preconfig pause QEMU before machine is initialized (experimental)\n", 3238 QEMU_ARCH_ALL) 3239STEXI 3240@item --preconfig 3241@findex --preconfig 3242Pause QEMU for interactive configuration before the machine is created, 3243which allows querying and configuring properties that will affect 3244machine initialization. Use QMP command 'x-exit-preconfig' to exit 3245the preconfig state and move to the next state (i.e. run guest if -S 3246isn't used or pause the second time if -S is used). This option is 3247experimental. 3248ETEXI 3249 3250DEF("S", 0, QEMU_OPTION_S, \ 3251 "-S freeze CPU at startup (use 'c' to start execution)\n", 3252 QEMU_ARCH_ALL) 3253STEXI 3254@item -S 3255@findex -S 3256Do not start CPU at startup (you must type 'c' in the monitor). 3257ETEXI 3258 3259DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3260 "-realtime [mlock=on|off]\n" 3261 " run qemu with realtime features\n" 3262 " mlock=on|off controls mlock support (default: on)\n", 3263 QEMU_ARCH_ALL) 3264STEXI 3265@item -realtime mlock=on|off 3266@findex -realtime 3267Run qemu with realtime features. 3268mlocking qemu and guest memory can be enabled via @option{mlock=on} 3269(enabled by default). 3270ETEXI 3271 3272DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit, 3273 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n" 3274 " run qemu with overcommit hints\n" 3275 " mem-lock=on|off controls memory lock support (default: off)\n" 3276 " cpu-pm=on|off controls cpu power management (default: off)\n", 3277 QEMU_ARCH_ALL) 3278STEXI 3279@item -overcommit mem-lock=on|off 3280@item -overcommit cpu-pm=on|off 3281@findex -overcommit 3282Run qemu with hints about host resource overcommit. The default is 3283to assume that host overcommits all resources. 3284 3285Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled 3286by default). This works when host memory is not overcommitted and reduces the 3287worst-case latency for guest. This is equivalent to @option{realtime}. 3288 3289Guest ability to manage power state of host cpus (increasing latency for other 3290processes on the same host cpu, but decreasing latency for guest) can be 3291enabled via @option{cpu-pm=on} (disabled by default). This works best when 3292host CPU is not overcommitted. When used, host estimates of CPU cycle and power 3293utilization will be incorrect, not taking into account guest idle time. 3294ETEXI 3295 3296DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3297 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3298STEXI 3299@item -gdb @var{dev} 3300@findex -gdb 3301Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3302connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3303stdio are reasonable use case. The latter is allowing to start QEMU from 3304within gdb and establish the connection via a pipe: 3305@example 3306(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3307@end example 3308ETEXI 3309 3310DEF("s", 0, QEMU_OPTION_s, \ 3311 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3312 QEMU_ARCH_ALL) 3313STEXI 3314@item -s 3315@findex -s 3316Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3317(@pxref{gdb_usage}). 3318ETEXI 3319 3320DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3321 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3322 QEMU_ARCH_ALL) 3323STEXI 3324@item -d @var{item1}[,...] 3325@findex -d 3326Enable logging of specified items. Use '-d help' for a list of log items. 3327ETEXI 3328 3329DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3330 "-D logfile output log to logfile (default stderr)\n", 3331 QEMU_ARCH_ALL) 3332STEXI 3333@item -D @var{logfile} 3334@findex -D 3335Output log in @var{logfile} instead of to stderr 3336ETEXI 3337 3338DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3339 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3340 QEMU_ARCH_ALL) 3341STEXI 3342@item -dfilter @var{range1}[,...] 3343@findex -dfilter 3344Filter debug output to that relevant to a range of target addresses. The filter 3345spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3346@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3347addresses and sizes required. For example: 3348@example 3349 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3350@end example 3351Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3352the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3353block starting at 0xffffffc00005f000. 3354ETEXI 3355 3356DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3357 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3358 QEMU_ARCH_ALL) 3359STEXI 3360@item -L @var{path} 3361@findex -L 3362Set the directory for the BIOS, VGA BIOS and keymaps. 3363 3364To list all the data directories, use @code{-L help}. 3365ETEXI 3366 3367DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3368 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3369STEXI 3370@item -bios @var{file} 3371@findex -bios 3372Set the filename for the BIOS. 3373ETEXI 3374 3375DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3376 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3377STEXI 3378@item -enable-kvm 3379@findex -enable-kvm 3380Enable KVM full virtualization support. This option is only available 3381if KVM support is enabled when compiling. 3382ETEXI 3383 3384DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \ 3385 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386) 3386STEXI 3387@item -enable-hax 3388@findex -enable-hax 3389Enable HAX (Hardware-based Acceleration eXecution) support. This option 3390is only available if HAX support is enabled when compiling. HAX is only 3391applicable to MAC and Windows platform, and thus does not conflict with 3392KVM. This option is deprecated, use @option{-accel hax} instead. 3393ETEXI 3394 3395DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3396 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3397DEF("xen-create", 0, QEMU_OPTION_xen_create, 3398 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3399 " warning: should not be used when xend is in use\n", 3400 QEMU_ARCH_ALL) 3401DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3402 "-xen-attach attach to existing xen domain\n" 3403 " xend 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-create 3415@findex -xen-create 3416Create domain using xen hypercalls, bypassing xend. 3417Warning: should not be used when xend is in use (XEN only). 3418@item -xen-attach 3419@findex -xen-attach 3420Attach to existing xen domain. 3421xend will use this when starting QEMU (XEN only). 3422@findex -xen-domid-restrict 3423Restrict set of available xen operations to specified domain id (XEN only). 3424ETEXI 3425 3426DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3427 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3428STEXI 3429@item -no-reboot 3430@findex -no-reboot 3431Exit instead of rebooting. 3432ETEXI 3433 3434DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3435 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3436STEXI 3437@item -no-shutdown 3438@findex -no-shutdown 3439Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3440This allows for instance switching to monitor to commit changes to the 3441disk image. 3442ETEXI 3443 3444DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3445 "-loadvm [tag|id]\n" \ 3446 " start right away with a saved state (loadvm in monitor)\n", 3447 QEMU_ARCH_ALL) 3448STEXI 3449@item -loadvm @var{file} 3450@findex -loadvm 3451Start right away with a saved state (@code{loadvm} in monitor) 3452ETEXI 3453 3454#ifndef _WIN32 3455DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3456 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3457#endif 3458STEXI 3459@item -daemonize 3460@findex -daemonize 3461Daemonize the QEMU process after initialization. QEMU will not detach from 3462standard IO until it is ready to receive connections on any of its devices. 3463This option is a useful way for external programs to launch QEMU without having 3464to cope with initialization race conditions. 3465ETEXI 3466 3467DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3468 "-option-rom rom load a file, rom, into the option ROM space\n", 3469 QEMU_ARCH_ALL) 3470STEXI 3471@item -option-rom @var{file} 3472@findex -option-rom 3473Load the contents of @var{file} as an option ROM. 3474This option is useful to load things like EtherBoot. 3475ETEXI 3476 3477HXCOMM Silently ignored for compatibility 3478DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3479 3480DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3481 "-rtc [base=utc|localtime|<datetime>][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3482 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3483 QEMU_ARCH_ALL) 3484 3485STEXI 3486 3487@item -rtc [base=utc|localtime|@var{datetime}][,clock=host|rt|vm][,driftfix=none|slew] 3488@findex -rtc 3489Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3490UTC or local time, respectively. @code{localtime} is required for correct date in 3491MS-DOS or Windows. To start at a specific point in time, provide @var{datetime} in the 3492format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3493 3494By default the RTC is driven by the host system time. This allows using of the 3495RTC as accurate reference clock inside the guest, specifically if the host 3496time is smoothly following an accurate external reference clock, e.g. via NTP. 3497If you want to isolate the guest time from the host, you can set @option{clock} 3498to @code{rt} instead, which provides a host monotonic clock if host support it. 3499To even prevent the RTC from progressing during suspension, you can set @option{clock} 3500to @code{vm} (virtual clock). @samp{clock=vm} is recommended especially in 3501icount mode in order to preserve determinism; however, note that in icount mode 3502the speed of the virtual clock is variable and can in general differ from the 3503host clock. 3504 3505Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3506specifically with Windows' ACPI HAL. This option will try to figure out how 3507many timer interrupts were not processed by the Windows guest and will 3508re-inject them. 3509ETEXI 3510 3511DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3512 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3513 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3514 " instruction, enable aligning the host and virtual clocks\n" \ 3515 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3516STEXI 3517@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3518@findex -icount 3519Enable virtual instruction counter. The virtual cpu will execute one 3520instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3521then the virtual cpu speed will be automatically adjusted to keep virtual 3522time within a few seconds of real time. 3523 3524When the virtual cpu is sleeping, the virtual time will advance at default 3525speed unless @option{sleep=on|off} is specified. 3526With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3527instantly whenever the virtual cpu goes to sleep mode and will not advance 3528if no timer is enabled. This behavior give deterministic execution times from 3529the guest point of view. 3530 3531Note that while this option can give deterministic behavior, it does not 3532provide cycle accurate emulation. Modern CPUs contain superscalar out of 3533order cores with complex cache hierarchies. The number of instructions 3534executed often has little or no correlation with actual performance. 3535 3536@option{align=on} will activate the delay algorithm which will try 3537to synchronise the host clock and the virtual clock. The goal is to 3538have a guest running at the real frequency imposed by the shift option. 3539Whenever the guest clock is behind the host clock and if 3540@option{align=on} is specified then we print a message to the user 3541to inform about the delay. 3542Currently this option does not work when @option{shift} is @code{auto}. 3543Note: The sync algorithm will work for those shift values for which 3544the guest clock runs ahead of the host clock. Typically this happens 3545when the shift value is high (how high depends on the host machine). 3546 3547When @option{rr} option is specified deterministic record/replay is enabled. 3548Replay log is written into @var{filename} file in record mode and 3549read from this file in replay mode. 3550 3551Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3552at the start of execution recording. In replay mode this option is used 3553to load the initial VM state. 3554ETEXI 3555 3556DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3557 "-watchdog model\n" \ 3558 " enable virtual hardware watchdog [default=none]\n", 3559 QEMU_ARCH_ALL) 3560STEXI 3561@item -watchdog @var{model} 3562@findex -watchdog 3563Create a virtual hardware watchdog device. Once enabled (by a guest 3564action), the watchdog must be periodically polled by an agent inside 3565the guest or else the guest will be restarted. Choose a model for 3566which your guest has drivers. 3567 3568The @var{model} is the model of hardware watchdog to emulate. Use 3569@code{-watchdog help} to list available hardware models. Only one 3570watchdog can be enabled for a guest. 3571 3572The following models may be available: 3573@table @option 3574@item ib700 3575iBASE 700 is a very simple ISA watchdog with a single timer. 3576@item i6300esb 3577Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3578dual-timer watchdog. 3579@item diag288 3580A virtual watchdog for s390x backed by the diagnose 288 hypercall 3581(currently KVM only). 3582@end table 3583ETEXI 3584 3585DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3586 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \ 3587 " action when watchdog fires [default=reset]\n", 3588 QEMU_ARCH_ALL) 3589STEXI 3590@item -watchdog-action @var{action} 3591@findex -watchdog-action 3592 3593The @var{action} controls what QEMU will do when the watchdog timer 3594expires. 3595The default is 3596@code{reset} (forcefully reset the guest). 3597Other possible actions are: 3598@code{shutdown} (attempt to gracefully shutdown the guest), 3599@code{poweroff} (forcefully poweroff the guest), 3600@code{inject-nmi} (inject a NMI into the guest), 3601@code{pause} (pause the guest), 3602@code{debug} (print a debug message and continue), or 3603@code{none} (do nothing). 3604 3605Note that the @code{shutdown} action requires that the guest responds 3606to ACPI signals, which it may not be able to do in the sort of 3607situations where the watchdog would have expired, and thus 3608@code{-watchdog-action shutdown} is not recommended for production use. 3609 3610Examples: 3611 3612@table @code 3613@item -watchdog i6300esb -watchdog-action pause 3614@itemx -watchdog ib700 3615@end table 3616ETEXI 3617 3618DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3619 "-echr chr set terminal escape character instead of ctrl-a\n", 3620 QEMU_ARCH_ALL) 3621STEXI 3622 3623@item -echr @var{numeric_ascii_value} 3624@findex -echr 3625Change the escape character used for switching to the monitor when using 3626monitor and serial sharing. The default is @code{0x01} when using the 3627@code{-nographic} option. @code{0x01} is equal to pressing 3628@code{Control-a}. You can select a different character from the ascii 3629control keys where 1 through 26 map to Control-a through Control-z. For 3630instance you could use the either of the following to change the escape 3631character to Control-t. 3632@table @code 3633@item -echr 0x14 3634@itemx -echr 20 3635@end table 3636ETEXI 3637 3638DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3639 "-virtioconsole c\n" \ 3640 " set virtio console\n", QEMU_ARCH_ALL) 3641STEXI 3642@item -virtioconsole @var{c} 3643@findex -virtioconsole 3644Set virtio console. 3645This option is deprecated, please use @option{-device virtconsole} instead. 3646ETEXI 3647 3648DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3649 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3650STEXI 3651@item -show-cursor 3652@findex -show-cursor 3653Show cursor. 3654ETEXI 3655 3656DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3657 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3658STEXI 3659@item -tb-size @var{n} 3660@findex -tb-size 3661Set TB size. 3662ETEXI 3663 3664DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3665 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3666 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3667 "-incoming unix:socketpath\n" \ 3668 " prepare for incoming migration, listen on\n" \ 3669 " specified protocol and socket address\n" \ 3670 "-incoming fd:fd\n" \ 3671 "-incoming exec:cmdline\n" \ 3672 " accept incoming migration on given file descriptor\n" \ 3673 " or from given external command\n" \ 3674 "-incoming defer\n" \ 3675 " wait for the URI to be specified via migrate_incoming\n", 3676 QEMU_ARCH_ALL) 3677STEXI 3678@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3679@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3680@findex -incoming 3681Prepare for incoming migration, listen on a given tcp port. 3682 3683@item -incoming unix:@var{socketpath} 3684Prepare for incoming migration, listen on a given unix socket. 3685 3686@item -incoming fd:@var{fd} 3687Accept incoming migration from a given filedescriptor. 3688 3689@item -incoming exec:@var{cmdline} 3690Accept incoming migration as an output from specified external command. 3691 3692@item -incoming defer 3693Wait for the URI to be specified via migrate_incoming. The monitor can 3694be used to change settings (such as migration parameters) prior to issuing 3695the migrate_incoming to allow the migration to begin. 3696ETEXI 3697 3698DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3699 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3700STEXI 3701@item -only-migratable 3702@findex -only-migratable 3703Only allow migratable devices. Devices will not be allowed to enter an 3704unmigratable state. 3705ETEXI 3706 3707DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3708 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3709STEXI 3710@item -nodefaults 3711@findex -nodefaults 3712Don't create default devices. Normally, QEMU sets the default devices like serial 3713port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3714CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3715default devices. 3716ETEXI 3717 3718#ifndef _WIN32 3719DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3720 "-chroot dir chroot to dir just before starting the VM\n", 3721 QEMU_ARCH_ALL) 3722#endif 3723STEXI 3724@item -chroot @var{dir} 3725@findex -chroot 3726Immediately before starting guest execution, chroot to the specified 3727directory. Especially useful in combination with -runas. 3728ETEXI 3729 3730#ifndef _WIN32 3731DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3732 "-runas user change to user id user just before starting the VM\n" \ 3733 " user can be numeric uid:gid instead\n", 3734 QEMU_ARCH_ALL) 3735#endif 3736STEXI 3737@item -runas @var{user} 3738@findex -runas 3739Immediately before starting guest execution, drop root privileges, switching 3740to the specified user. 3741ETEXI 3742 3743DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3744 "-prom-env variable=value\n" 3745 " set OpenBIOS nvram variables\n", 3746 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3747STEXI 3748@item -prom-env @var{variable}=@var{value} 3749@findex -prom-env 3750Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3751ETEXI 3752DEF("semihosting", 0, QEMU_OPTION_semihosting, 3753 "-semihosting semihosting mode\n", 3754 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3755 QEMU_ARCH_MIPS) 3756STEXI 3757@item -semihosting 3758@findex -semihosting 3759Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3760ETEXI 3761DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3762 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3763 " semihosting configuration\n", 3764QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3765QEMU_ARCH_MIPS) 3766STEXI 3767@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3768@findex -semihosting-config 3769Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3770@table @option 3771@item target=@code{native|gdb|auto} 3772Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3773or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3774during debug sessions and @code{native} otherwise. 3775@item arg=@var{str1},arg=@var{str2},... 3776Allows the user to pass input arguments, and can be used multiple times to build 3777up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3778command line is still supported for backward compatibility. If both the 3779@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3780specified, the former is passed to semihosting as it always takes precedence. 3781@end table 3782ETEXI 3783DEF("old-param", 0, QEMU_OPTION_old_param, 3784 "-old-param old param mode\n", QEMU_ARCH_ARM) 3785STEXI 3786@item -old-param 3787@findex -old-param (ARM) 3788Old param mode (ARM only). 3789ETEXI 3790 3791DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3792 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \ 3793 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \ 3794 " Enable seccomp mode 2 system call filter (default 'off').\n" \ 3795 " use 'obsolete' to allow obsolete system calls that are provided\n" \ 3796 " by the kernel, but typically no longer used by modern\n" \ 3797 " C library implementations.\n" \ 3798 " use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \ 3799 " its privileges by blacklisting all set*uid|gid system calls.\n" \ 3800 " The value 'children' will deny set*uid|gid system calls for\n" \ 3801 " main QEMU process but will allow forks and execves to run unprivileged\n" \ 3802 " use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \ 3803 " blacklisting *fork and execve\n" \ 3804 " use 'resourcecontrol' to disable process affinity and schedular priority\n", 3805 QEMU_ARCH_ALL) 3806STEXI 3807@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}] 3808@findex -sandbox 3809Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3810disable it. The default is 'off'. 3811@table @option 3812@item obsolete=@var{string} 3813Enable Obsolete system calls 3814@item elevateprivileges=@var{string} 3815Disable set*uid|gid system calls 3816@item spawn=@var{string} 3817Disable *fork and execve 3818@item resourcecontrol=@var{string} 3819Disable process affinity and schedular priority 3820@end table 3821ETEXI 3822 3823DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3824 "-readconfig <file>\n", QEMU_ARCH_ALL) 3825STEXI 3826@item -readconfig @var{file} 3827@findex -readconfig 3828Read device configuration from @var{file}. This approach is useful when you want to spawn 3829QEMU process with many command line options but you don't want to exceed the command line 3830character limit. 3831ETEXI 3832DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3833 "-writeconfig <file>\n" 3834 " read/write config file\n", QEMU_ARCH_ALL) 3835STEXI 3836@item -writeconfig @var{file} 3837@findex -writeconfig 3838Write device configuration to @var{file}. The @var{file} can be either filename to save 3839command line and device configuration into file or dash @code{-}) character to print the 3840output to stdout. This can be later used as input file for @code{-readconfig} option. 3841ETEXI 3842 3843DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3844 "-no-user-config\n" 3845 " do not load default user-provided config files at startup\n", 3846 QEMU_ARCH_ALL) 3847STEXI 3848@item -no-user-config 3849@findex -no-user-config 3850The @code{-no-user-config} option makes QEMU not load any of the user-provided 3851config files on @var{sysconfdir}. 3852ETEXI 3853 3854DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3855 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3856 " specify tracing options\n", 3857 QEMU_ARCH_ALL) 3858STEXI 3859HXCOMM This line is not accurate, as some sub-options are backend-specific but 3860HXCOMM HX does not support conditional compilation of text. 3861@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 3862@findex -trace 3863@include qemu-option-trace.texi 3864ETEXI 3865 3866HXCOMM Internal use 3867DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3868DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3869 3870#ifdef __linux__ 3871DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3872 "-enable-fips enable FIPS 140-2 compliance\n", 3873 QEMU_ARCH_ALL) 3874#endif 3875STEXI 3876@item -enable-fips 3877@findex -enable-fips 3878Enable FIPS 140-2 compliance mode. 3879ETEXI 3880 3881HXCOMM Deprecated by -machine accel=tcg property 3882DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3883 3884DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3885 "-msg timestamp[=on|off]\n" 3886 " change the format of messages\n" 3887 " on|off controls leading timestamps (default:on)\n", 3888 QEMU_ARCH_ALL) 3889STEXI 3890@item -msg timestamp[=on|off] 3891@findex -msg 3892prepend a timestamp to each log message.(default:on) 3893ETEXI 3894 3895DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3896 "-dump-vmstate <file>\n" 3897 " Output vmstate information in JSON format to file.\n" 3898 " Use the scripts/vmstate-static-checker.py file to\n" 3899 " check for possible regressions in migration code\n" 3900 " by comparing two such vmstate dumps.\n", 3901 QEMU_ARCH_ALL) 3902STEXI 3903@item -dump-vmstate @var{file} 3904@findex -dump-vmstate 3905Dump json-encoded vmstate information for current machine type to file 3906in @var{file} 3907ETEXI 3908 3909DEF("enable-sync-profile", 0, QEMU_OPTION_enable_sync_profile, 3910 "-enable-sync-profile\n" 3911 " enable synchronization profiling\n", 3912 QEMU_ARCH_ALL) 3913STEXI 3914@item -enable-sync-profile 3915@findex -enable-sync-profile 3916Enable synchronization profiling. 3917ETEXI 3918 3919STEXI 3920@end table 3921ETEXI 3922DEFHEADING() 3923 3924DEFHEADING(Generic object creation:) 3925STEXI 3926@table @option 3927ETEXI 3928 3929DEF("object", HAS_ARG, QEMU_OPTION_object, 3930 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3931 " create a new object of type TYPENAME setting properties\n" 3932 " in the order they are specified. Note that the 'id'\n" 3933 " property must be set. These objects are placed in the\n" 3934 " '/objects' path.\n", 3935 QEMU_ARCH_ALL) 3936STEXI 3937@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3938@findex -object 3939Create a new object of type @var{typename} setting properties 3940in the order they are specified. Note that the 'id' 3941property must be set. These objects are placed in the 3942'/objects' path. 3943 3944@table @option 3945 3946@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} 3947 3948Creates a memory file backend object, which can be used to back 3949the guest RAM with huge pages. 3950 3951The @option{id} parameter is a unique ID that will be used to reference this 3952memory region when configuring the @option{-numa} argument. 3953 3954The @option{size} option provides the size of the memory region, and accepts 3955common suffixes, eg @option{500M}. 3956 3957The @option{mem-path} provides the path to either a shared memory or huge page 3958filesystem mount. 3959 3960The @option{share} boolean option determines whether the memory 3961region is marked as private to QEMU, or shared. The latter allows 3962a co-operating external process to access the QEMU memory region. 3963 3964The @option{share} is also required for pvrdma devices due to 3965limitations in the RDMA API provided by Linux. 3966 3967Setting share=on might affect the ability to configure NUMA 3968bindings for the memory backend under some circumstances, see 3969Documentation/vm/numa_memory_policy.txt on the Linux kernel 3970source tree for additional details. 3971 3972Setting the @option{discard-data} boolean option to @var{on} 3973indicates that file contents can be destroyed when QEMU exits, 3974to avoid unnecessarily flushing data to the backing file. Note 3975that @option{discard-data} is only an optimization, and QEMU 3976might not discard file contents if it aborts unexpectedly or is 3977terminated using SIGKILL. 3978 3979The @option{merge} boolean option enables memory merge, also known as 3980MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for 3981memory deduplication. 3982 3983Setting the @option{dump} boolean option to @var{off} excludes the memory from 3984core dumps. This feature is also known as MADV_DONTDUMP. 3985 3986The @option{prealloc} boolean option enables memory preallocation. 3987 3988The @option{host-nodes} option binds the memory range to a list of NUMA host 3989nodes. 3990 3991The @option{policy} option sets the NUMA policy to one of the following values: 3992 3993@table @option 3994@item @var{default} 3995default host policy 3996 3997@item @var{preferred} 3998prefer the given host node list for allocation 3999 4000@item @var{bind} 4001restrict memory allocation to the given host node list 4002 4003@item @var{interleave} 4004interleave memory allocations across the given host node list 4005@end table 4006 4007The @option{align} option specifies the base address alignment when 4008QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg 4009@option{2M}. Some backend store specified by @option{mem-path} 4010requires an alignment different than the default one used by QEMU, eg 4011the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In 4012such cases, users can specify the required alignment via this option. 4013 4014The @option{pmem} option specifies whether the backing file specified 4015by @option{mem-path} is in host persistent memory that can be accessed 4016using the SNIA NVM programming model (e.g. Intel NVDIMM). 4017If @option{pmem} is set to 'on', QEMU will take necessary operations to 4018guarantee the persistence of its own writes to @option{mem-path} 4019(e.g. in vNVDIMM label emulation and live migration). 4020 4021@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} 4022 4023Creates a memory backend object, which can be used to back the guest RAM. 4024Memory backend objects offer more control than the @option{-m} option that is 4025traditionally used to define guest RAM. Please refer to 4026@option{memory-backend-file} for a description of the options. 4027 4028@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} 4029 4030Creates an anonymous memory file backend object, which allows QEMU to 4031share the memory with an external process (e.g. when using 4032vhost-user). The memory is allocated with memfd and optional 4033sealing. (Linux only) 4034 4035The @option{seal} option creates a sealed-file, that will block 4036further resizing the memory ('on' by default). 4037 4038The @option{hugetlb} option specify the file to be created resides in 4039the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with 4040the @option{hugetlb} option, the @option{hugetlbsize} option specify 4041the hugetlb page size on systems that support multiple hugetlb page 4042sizes (it must be a power of 2 value supported by the system). 4043 4044In some versions of Linux, the @option{hugetlb} option is incompatible 4045with the @option{seal} option (requires at least Linux 4.16). 4046 4047Please refer to @option{memory-backend-file} for a description of the 4048other options. 4049 4050The @option{share} boolean option is @var{on} by default with memfd. 4051 4052@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4053 4054Creates a random number generator backend which obtains entropy from 4055a device on the host. The @option{id} parameter is a unique ID that 4056will be used to reference this entropy backend from the @option{virtio-rng} 4057device. The @option{filename} parameter specifies which file to obtain 4058entropy from and if omitted defaults to @option{/dev/random}. 4059 4060@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4061 4062Creates a random number generator backend which obtains entropy from 4063an external daemon running on the host. The @option{id} parameter is 4064a unique ID that will be used to reference this entropy backend from 4065the @option{virtio-rng} device. The @option{chardev} parameter is 4066the unique ID of a character device backend that provides the connection 4067to the RNG daemon. 4068 4069@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4070 4071Creates a TLS anonymous credentials object, which can be used to provide 4072TLS support on network backends. The @option{id} parameter is a unique 4073ID which network backends will use to access the credentials. The 4074@option{endpoint} is either @option{server} or @option{client} depending 4075on whether the QEMU network backend that uses the credentials will be 4076acting as a client or as a server. If @option{verify-peer} is enabled 4077(the default) then once the handshake is completed, the peer credentials 4078will be verified, though this is a no-op for anonymous credentials. 4079 4080The @var{dir} parameter tells QEMU where to find the credential 4081files. For server endpoints, this directory may contain a file 4082@var{dh-params.pem} providing diffie-hellman parameters to use 4083for the TLS server. If the file is missing, QEMU will generate 4084a set of DH parameters at startup. This is a computationally 4085expensive operation that consumes random pool entropy, so it is 4086recommended that a persistent set of parameters be generated 4087upfront and saved. 4088 4089@item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}] 4090 4091Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide 4092TLS support on network backends. The @option{id} parameter is a unique 4093ID which network backends will use to access the credentials. The 4094@option{endpoint} is either @option{server} or @option{client} depending 4095on whether the QEMU network backend that uses the credentials will be 4096acting as a client or as a server. For clients only, @option{username} 4097is the username which will be sent to the server. If omitted 4098it defaults to ``qemu''. 4099 4100The @var{dir} parameter tells QEMU where to find the keys file. 4101It is called ``@var{dir}/keys.psk'' and contains ``username:key'' 4102pairs. This file can most easily be created using the GnuTLS 4103@code{psktool} program. 4104 4105For server endpoints, @var{dir} may also contain a file 4106@var{dh-params.pem} providing diffie-hellman parameters to use 4107for the TLS server. If the file is missing, QEMU will generate 4108a set of DH parameters at startup. This is a computationally 4109expensive operation that consumes random pool entropy, so it is 4110recommended that a persistent set of parameters be generated 4111up front and saved. 4112 4113@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} 4114 4115Creates a TLS anonymous credentials object, which can be used to provide 4116TLS support on network backends. The @option{id} parameter is a unique 4117ID which network backends will use to access the credentials. The 4118@option{endpoint} is either @option{server} or @option{client} depending 4119on whether the QEMU network backend that uses the credentials will be 4120acting as a client or as a server. If @option{verify-peer} is enabled 4121(the default) then once the handshake is completed, the peer credentials 4122will be verified. With x509 certificates, this implies that the clients 4123must be provided with valid client certificates too. 4124 4125The @var{dir} parameter tells QEMU where to find the credential 4126files. For server endpoints, this directory may contain a file 4127@var{dh-params.pem} providing diffie-hellman parameters to use 4128for the TLS server. If the file is missing, QEMU will generate 4129a set of DH parameters at startup. This is a computationally 4130expensive operation that consumes random pool entropy, so it is 4131recommended that a persistent set of parameters be generated 4132upfront and saved. 4133 4134For x509 certificate credentials the directory will contain further files 4135providing the x509 certificates. The certificates must be stored 4136in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4137@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4138@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4139 4140For the @var{server-key.pem} and @var{client-key.pem} files which 4141contain sensitive private keys, it is possible to use an encrypted 4142version by providing the @var{passwordid} parameter. This provides 4143the ID of a previously created @code{secret} object containing the 4144password for decryption. 4145 4146The @var{priority} parameter allows to override the global default 4147priority used by gnutls. This can be useful if the system administrator 4148needs to use a weaker set of crypto priorities for QEMU without 4149potentially forcing the weakness onto all applications. Or conversely 4150if one wants wants a stronger default for QEMU than for all other 4151applications, they can do this through this parameter. Its format is 4152a gnutls priority string as described at 4153@url{https://gnutls.org/manual/html_node/Priority-Strings.html}. 4154 4155@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4156 4157Interval @var{t} can't be 0, this filter batches the packet delivery: all 4158packets arriving in a given interval on netdev @var{netdevid} are delayed 4159until the end of the interval. Interval is in microseconds. 4160@option{status} is optional that indicate whether the netfilter is 4161on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4162 4163queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4164 4165@option{all}: the filter is attached both to the receive and the transmit 4166 queue of the netdev (default). 4167 4168@option{rx}: the filter is attached to the receive queue of the netdev, 4169 where it will receive packets sent to the netdev. 4170 4171@option{tx}: the filter is attached to the transmit queue of the netdev, 4172 where it will receive packets sent by the netdev. 4173 4174@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4175 4176filter-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. 4177 4178@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support] 4179 4180filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4181@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag, 4182filter-redirector will redirect packet with vnet_hdr_len. 4183Create a filter-redirector we need to differ outdev id from indev id, id can not 4184be the same. we can just use indev or outdev, but at least one of indev or outdev 4185need to be specified. 4186 4187@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support] 4188 4189Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4190secondary from primary to keep secondary tcp connection,and rewrite 4191tcp packet to primary from secondary make tcp packet can be handled by 4192client.if it has the vnet_hdr_support flag, we can parse packet with vnet header. 4193 4194usage: 4195colo secondary: 4196-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4197-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4198-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4199 4200@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4201 4202Dump the network traffic on netdev @var{dev} to the file specified by 4203@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4204The file format is libpcap, so it can be analyzed with tools such as tcpdump 4205or Wireshark. 4206 4207@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support] 4208 4209Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4210secondary packet. If the packets are same, we will output primary 4211packet to outdev@var{chardevid}, else we will notify colo-frame 4212do checkpoint and send primary packet to outdev@var{chardevid}. 4213if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len. 4214 4215we must use it with the help of filter-mirror and filter-redirector. 4216 4217@example 4218 4219primary: 4220-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4221-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4222-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4223-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4224-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4225-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4226-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4227-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4228-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4229-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4230-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4231-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4232 4233secondary: 4234-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4235-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4236-chardev socket,id=red0,host=3.3.3.3,port=9003 4237-chardev socket,id=red1,host=3.3.3.3,port=9004 4238-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4239-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4240 4241@end example 4242 4243If you want to know the detail of above command line, you can read 4244the colo-compare git log. 4245 4246@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4247 4248Creates a cryptodev backend which executes crypto opreation from 4249the QEMU cipher APIS. The @var{id} parameter is 4250a unique ID that will be used to reference this cryptodev backend from 4251the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4252which specify the queue number of cryptodev backend, the default of 4253@var{queues} is 1. 4254 4255@example 4256 4257 # qemu-system-x86_64 \ 4258 [...] \ 4259 -object cryptodev-backend-builtin,id=cryptodev0 \ 4260 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4261 [...] 4262@end example 4263 4264@item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}] 4265 4266Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}. 4267The @var{id} parameter is a unique ID that will be used to reference this 4268cryptodev backend from the @option{virtio-crypto} device. 4269The chardev should be a unix domain socket backed one. The vhost-user uses 4270a specifically defined protocol to pass vhost ioctl replacement messages 4271to an application on the other end of the socket. 4272The @var{queues} parameter is optional, which specify the queue number 4273of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1. 4274 4275@example 4276 4277 # qemu-system-x86_64 \ 4278 [...] \ 4279 -chardev socket,id=chardev0,path=/path/to/socket \ 4280 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \ 4281 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4282 [...] 4283@end example 4284 4285@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4286@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4287 4288Defines a secret to store a password, encryption key, or some other sensitive 4289data. The sensitive data can either be passed directly via the @var{data} 4290parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4291parameter is insecure unless the sensitive data is encrypted. 4292 4293The sensitive data can be provided in raw format (the default), or base64. 4294When encoded as JSON, the raw format only supports valid UTF-8 characters, 4295so base64 is recommended for sending binary data. QEMU will convert from 4296which ever format is provided to the format it needs internally. eg, an 4297RBD password can be provided in raw format, even though it will be base64 4298encoded when passed onto the RBD sever. 4299 4300For added protection, it is possible to encrypt the data associated with 4301a secret using the AES-256-CBC cipher. Use of encryption is indicated 4302by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4303parameter provides the ID of a previously defined secret that contains 4304the AES-256 decryption key. This key should be 32-bytes long and be 4305base64 encoded. The @var{iv} parameter provides the random initialization 4306vector used for encryption of this particular secret and should be a 4307base64 encrypted string of the 16-byte IV. 4308 4309The simplest (insecure) usage is to provide the secret inline 4310 4311@example 4312 4313 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4314 4315@end example 4316 4317The simplest secure usage is to provide the secret via a file 4318 4319 # printf "letmein" > mypasswd.txt 4320 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4321 4322For greater security, AES-256-CBC should be used. To illustrate usage, 4323consider the openssl command line tool which can encrypt the data. Note 4324that when encrypting, the plaintext must be padded to the cipher block 4325size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4326 4327First a master key needs to be created in base64 encoding: 4328 4329@example 4330 # openssl rand -base64 32 > key.b64 4331 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4332@end example 4333 4334Each secret to be encrypted needs to have a random initialization vector 4335generated. These do not need to be kept secret 4336 4337@example 4338 # openssl rand -base64 16 > iv.b64 4339 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4340@end example 4341 4342The secret to be defined can now be encrypted, in this case we're 4343telling openssl to base64 encode the result, but it could be left 4344as raw bytes if desired. 4345 4346@example 4347 # SECRET=$(printf "letmein" | 4348 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4349@end example 4350 4351When launching QEMU, create a master secret pointing to @code{key.b64} 4352and specify that to be used to decrypt the user password. Pass the 4353contents of @code{iv.b64} to the second secret 4354 4355@example 4356 # $QEMU \ 4357 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4358 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4359 data=$SECRET,iv=$(<iv.b64) 4360@end example 4361 4362@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}] 4363 4364Create a Secure Encrypted Virtualization (SEV) guest object, which can be used 4365to provide the guest memory encryption support on AMD processors. 4366 4367When memory encryption is enabled, one of the physical address bit (aka the 4368C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos} 4369is used to provide the C-bit position. The C-bit position is Host family dependent 4370hence user must provide this value. On EPYC, the value should be 47. 4371 4372When memory encryption is enabled, we loose certain bits in physical address space. 4373The @option{reduced-phys-bits} is used to provide the number of bits we loose in 4374physical address space. Similar to C-bit, the value is Host family dependent. 4375On EPYC, the value should be 5. 4376 4377The @option{sev-device} provides the device file to use for communicating with 4378the SEV firmware running inside AMD Secure Processor. The default device is 4379'/dev/sev'. If hardware supports memory encryption then /dev/sev devices are 4380created by CCP driver. 4381 4382The @option{policy} provides the guest policy to be enforced by the SEV firmware 4383and restrict what configuration and operational commands can be performed on this 4384guest by the hypervisor. The policy should be provided by the guest owner and is 4385bound to the guest and cannot be changed throughout the lifetime of the guest. 4386The default is 0. 4387 4388If guest @option{policy} allows sharing the key with another SEV guest then 4389@option{handle} can be use to provide handle of the guest from which to share 4390the key. 4391 4392The @option{dh-cert-file} and @option{session-file} provides the guest owner's 4393Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters 4394are used for establishing a cryptographic session with the guest owner to 4395negotiate keys used for attestation. The file must be encoded in base64. 4396 4397e.g to launch a SEV guest 4398@example 4399 # $QEMU \ 4400 ...... 4401 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \ 4402 -machine ...,memory-encryption=sev0 4403 ..... 4404 4405@end example 4406@end table 4407 4408ETEXI 4409 4410 4411HXCOMM This is the last statement. Insert new options before this line! 4412STEXI 4413@end table 4414ETEXI 4415
