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r!man qemu

QEMU(1)                                                                QEMU(1)



NAME
       qemu-doc - QEMU Emulator User Documentation

SYNOPSIS
       usage: qemu [options] [disk_image]

DESCRIPTION
       The QEMU PC System emulator simulates the following peripherals:

       -   i440FX host PCI bridge and PIIX3 PCI to ISA bridge

       -   Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
           extensions (hardware level, including all non standard modes).

       -   PS/2 mouse and keyboard

       -   2 PCI IDE interfaces with hard disk and CD-ROM support

       -   Floppy disk

       -   PCI/ISA PCI network adapters

       -   Serial ports

       -   Creative SoundBlaster 16 sound card

       -   ENSONIQ AudioPCI ES1370 sound card

       -   Adlib(OPL2) - Yamaha YM3812 compatible chip

       -   PCI UHCI USB controller and a virtual USB hub.

       SMP is supported with up to 255 CPUs.

       Note that adlib is only available when QEMU was configured with
       -enable-adlib

       QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
       VGA BIOS.

       QEMU uses YM3812 emulation by Tatsuyuki Satoh.

OPTIONS
       disk_image is a raw hard disk image for IDE hard disk 0.

       General options:

       -M machine
           Select the emulated machine ("-M ?" for list)

       -fda file
       -fdb file
           Use file as floppy disk 0/1 image. You can use the host floppy by
           using /dev/fd0 as filename.

       -hda file
       -hdb file
       -hdc file
       -hdd file
           Use file as hard disk 0, 1, 2 or 3 image.

       -cdrom file
           Use file as CD-ROM image (you cannot use -hdc and -cdrom at the
           same time). You can use the host CD-ROM by using /dev/cdrom as
           filename.

       -drive option[,option[,option[,...]]]
           Define a new drive. Valid options are:

           "file=file"
               This option defines which disk image to use with this drive.

           "if=interface"
               This option defines on which type on interface the drive is
               connected.  Available types are: ide, scsi, sd, mtd, floppy,
               pflash.

           "bus=bus,unit=unit"
               These options define where is connected the drive by defining
               the bus number and the unit id.

           "index=index"
               This option defines where is connected the drive by using an
               index in the list of available connectors of a given interface
               type.

           "media=media"
               This option defines the type of the media: disk or cdrom.

           "cyls=c,heads=h,secs=s[,trans=t]"
               These options have the same definition as they have in -hdachs.

           "snapshot=snapshot"
               snapshot is "on" or "off" and allows to enable snapshot for
               given drive (see -snapshot).

           "cache=cache"
               cache is "on" or "off" and allows to disable host cache to
               access data.

           "format=format"
               Specify which disk format will be used rather than detecting
               the format.  Can be used to specifiy format=raw to avoid inter‐
               preting an untrusted format header.

           Instead of -cdrom you can use:

                   qemu -drive file=file,index=2,media=cdrom

           Instead of -hda, -hdb, -hdc, -hdd, you can use:

                   qemu -drive file=file,index=0,media=disk
                   qemu -drive file=file,index=1,media=disk
                   qemu -drive file=file,index=2,media=disk
                   qemu -drive file=file,index=3,media=disk

           You can connect a CDROM to the slave of ide0:

                   qemu -drive file=file,if=ide,index=1,media=cdrom

           If you don’t specify the "file=" argument, you define an empty
           drive:

                   qemu -drive if=ide,index=1,media=cdrom

           You can connect a SCSI disk with unit ID 6 on the bus #0:

                   qemu -drive file=file,if=scsi,bus=0,unit=6

           Instead of -fda, -fdb, you can use:

                   qemu -drive file=file,index=0,if=floppy
                   qemu -drive file=file,index=1,if=floppy

           By default, interface is "ide" and index is automatically incre‐
           mented:

                   qemu -drive file=a -drive file=b"

           is interpreted like:

                   qemu -hda a -hdb b

       -boot [a|c|d|n]
           Boot on floppy (a), hard disk (c), CD-ROM (d), or Etherboot (n).
           Hard disk boot is the default.

       -snapshot
           Write to temporary files instead of disk image files. In this case,
           the raw disk image you use is not written back. You can however
           force the write back by pressing C-a s.

       -no-fd-bootchk
           Disable boot signature checking for floppy disks in Bochs BIOS. It
           may be needed to boot from old floppy disks.

       -m megs
           Set virtual RAM size to megs megabytes. Default is 128 MiB.

       -smp n
           Simulate an SMP system with n CPUs. On the PC target, up to 255
           CPUs are supported. On Sparc32 target, Linux limits the number of
           usable CPUs to 4.

       -audio-help
           Will show the audio subsystem help: list of drivers, tunable param‐
           eters.

       -soundhw card1[,card2,...] or -soundhw all
           Enable audio and selected sound hardware. Use ? to print all avail‐
           able sound hardware.

                   qemu -soundhw sb16,adlib hda
                   qemu -soundhw es1370 hda
                   qemu -soundhw all hda
                   qemu -soundhw ?

       -localtime
           Set the real time clock to local time (the default is to UTC time).
           This option is needed to have correct date in MS-DOS or Windows.

       -startdate date
           Set the initial date of the real time clock. Valid format for date
           are: "now" or "2006-06-17T16:01:21" or "2006-06-17". The default
           value is "now".

       -pidfile file
           Store the QEMU process PID in file. It is useful if you launch QEMU
           from a script.

       -daemonize
           Daemonize the QEMU process after initialization.  QEMU will not
           detach from standard IO until it is ready to receive connections on
           any of its devices.  This option is a useful way for external pro‐
           grams to launch QEMU without having to cope with initialization
           race conditions.

       -win2k-hack
           Use it when installing Windows 2000 to avoid a disk full bug. After
           Windows 2000 is installed, you no longer need this option (this
           option slows down the IDE transfers).

       -option-rom file
           Load the contents of file as an option ROM.  This option is useful
           to load things like EtherBoot.

       -name name
           Sets the name of the guest.  This name will be display in the SDL
           window caption.  The name will also be used for the VNC server.

       Display options:

       -nographic
           Normally, QEMU uses SDL to display the VGA output. With this
           option, you can totally disable graphical output so that QEMU is a
           simple command line application. The emulated serial port is redi‐
           rected on the console. Therefore, you can still use QEMU to debug a
           Linux kernel with a serial console.

       -curses
           Normally, QEMU uses SDL to display the VGA output.  With this
           option, QEMU can display the VGA output when in text mode using a
           curses/ncurses interface.  Nothing is displayed in graphical mode.

       -no-frame
           Do not use decorations for SDL windows and start them using the
           whole available screen space. This makes the using QEMU in a dedi‐
           cated desktop workspace more convenient.

       -full-screen
           Start in full screen.

       -vnc display[,option[,option[,...]]]
           Normally, QEMU uses SDL to display the VGA output.  With this
           option, you can have QEMU listen on VNC display display and redi‐
           rect the VGA display over the VNC session.  It is very useful to
           enable the usb tablet device when using this option (option -usbdeâ€â€
           vice tablet). When using the VNC display, you must use the -k
           parameter to set the keyboard layout if you are not using en-us.
           Valid syntax for the display is

           "interface:d"
               TCP connections will only be allowed from interface on display
               d.  By convention the TCP port is 5900+d. Optionally, interface
               can be omitted in which case the server will bind to all inter‐
               faces.

           "unix:path"
               Connections will be allowed over UNIX domain sockets where path
               is the location of a unix socket to listen for connections on.

           "none"
               VNC is initialized by not started. The monitor "change" command
               can be used to later start the VNC server.

           Following the display value there may be one or more option flags
           separated by commas. Valid options are

           "password"
               Require that password based authentication is used for client
               connections.  The password must be set separately using the
               "change" command in the @ref{pcsys_monitor}

           "tls"
               Require that client use TLS when communicating with the VNC
               server. This uses anonymous TLS credentials so is susceptible
               to a man-in-the-middle attack. It is recommended that this
               option be combined with either the x509 or x509verify options.

           "x509=/path/to/certificate/dir"
               Valid if tls is specified. Require that x509 credentials are
               used for negotiating the TLS session. The server will send its
               x509 certificate to the client. It is recommended that a pass‐
               word be set on the VNC server to provide authentication of the
               client when this is used. The path following this option speci‐
               fies where the x509 certificates are to be loaded from.  See
               the @ref{vnc_security} section for details on generating cer‐
               tificates.

           "x509verify=/path/to/certificate/dir"
               Valid if tls is specified. Require that x509 credentials are
               used for negotiating the TLS session. The server will send its
               x509 certificate to the client, and request that the client
               send its own x509 certificate.  The server will validate the
               client’s certificate against the CA certificate, and reject
               clients when validation fails. If the certificate authority is
               trusted, this is a sufficient authentication mechanism. You may
               still wish to set a password on the VNC server as a second
               authentication layer. The path following this option specifies
               where the x509 certificates are to be loaded from. See the
               @ref{vnc_security} section for details on generating certifi‐
               cates.

       -k language
           Use keyboard layout language (for example "fr" for French). This
           option is only needed where it is not easy to get raw PC keycodes
           (e.g. on Macs, with some X11 servers or with a VNC display). You
           don’t normally need to use it on PC/Linux or PC/Windows hosts.

           The available layouts are:

                   ar  de-ch  es  fo     fr-ca  hu  ja  mk     no  pt-br  sv
                   da  en-gb  et  fr     fr-ch  is  lt  nl     pl  ru     th
                   de  en-us  fi  fr-be  hr     it  lv  nl-be  pt  sl     tr

           The default is "en-us".

       USB options:

       -usb
           Enable the USB driver (will be the default soon)

       -usbdevice devname
           Add the USB device devname.

           "mouse"
               Virtual Mouse. This will override the PS/2 mouse emulation when
               activated.

           "tablet"
               Pointer device that uses absolute coordinates (like a touch‐
               screen). This means qemu is able to report the mouse position
               without having to grab the mouse. Also overrides the PS/2 mouse
               emulation when activated.

           "disk:file"
               Mass storage device based on file

           "host:bus.addr"
               Pass through the host device identified by bus.addr (Linux
               only).

           "host:vendor_id:product_id"
               Pass through the host device identified by vendor_id:product_id
               (Linux only).

           "serial:[vendorid=vendor_id][,productid=product_id]:dev"
               Serial converter to host character device dev, see "-serial"
               for the available devices.

           "braille"
               Braille device.  This will use BrlAPI to display the braille
               output on a real or fake device.

       Network options:

       -net nic[,vlan=n][,macaddr=addr][,model=type]
           Create a new Network Interface Card and connect it to VLAN n (n = 0
           is the default). The NIC is an ne2k_pci by default on the PC tar‐
           get. Optionally, the MAC address can be changed. If no -net option
           is specified, a single NIC is created.  Qemu can emulate several
           different models of network card.  Valid values for type are
           "i82551", "i82557b", "i82559er", "ne2k_pci", "ne2k_isa", "pcnet",
           "rtl8139", "smc91c111", "lance" and "mcf_fec".  Not all devices are
           supported on all targets.  Use -net nic,model=?  for a list of
           available devices for your target.

       -net user[,vlan=n][,hostname=name]
           Use the user mode network stack which requires no administrator
           privilege to run.  hostname=name can be used to specify the client
           hostname reported by the builtin DHCP server.

       -net tap[,vlan=n][,fd=h][,ifname=name][,script=file]
           Connect the host TAP network interface name to VLAN n and use the
           network script file to configure it. The default network script is
           /etc/qemu-ifup. Use script=no to disable script execution. If name
           is not provided, the OS automatically provides one. fd=h can be
           used to specify the handle of an already opened host TAP interface.
           Example:

                   qemu linux.img -net nic -net tap

           More complicated example (two NICs, each one connected to a TAP
           device)

                   qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
                                  -net nic,vlan=1 -net tap,vlan=1,ifname=tap1

       -net socket[,vlan=n][,fd=h][,listen=[host]:port][,connect=host:port]
           Connect the VLAN n to a remote VLAN in another QEMU virtual machine
           using a TCP socket connection. If listen is specified, QEMU waits
           for incoming connections on port (host is optional). connect is
           used to connect to another QEMU instance using the listen option.
           fd=h specifies an already opened TCP socket.

           Example:

                   # launch a first QEMU instance
                   qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
                                  -net socket,listen=:1234
                   # connect the VLAN 0 of this instance to the VLAN 0
                   # of the first instance
                   qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
                                  -net socket,connect=127.0.0.1:1234

       -net socket[,vlan=n][,fd=h][,mcast=maddr:port]
           Create a VLAN n shared with another QEMU virtual machines using a
           UDP multicast socket, effectively making a bus for every QEMU with
           same multicast address maddr and port.  NOTES:

           1.  Several QEMU can be running on different hosts and share same
               bus (assuming correct multicast setup for these hosts).

           2.  mcast support is compatible with User Mode Linux (argument
               ethN=mcast), see <http://user-mode-linux.sf.net>.

           3.  Use fd=h to specify an already opened UDP multicast socket.

           Example:

                   # launch one QEMU instance
                   qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
                                  -net socket,mcast=230.0.0.1:1234
                   # launch another QEMU instance on same "bus"
                   qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
                                  -net socket,mcast=230.0.0.1:1234
                   # launch yet another QEMU instance on same "bus"
                   qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
                                  -net socket,mcast=230.0.0.1:1234

           Example (User Mode Linux compat.):

                   # launch QEMU instance (note mcast address selected
                   # is UML's default)
                   qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
                                  -net socket,mcast=239.192.168.1:1102
                   # launch UML
                   /path/to/linux ubd0=/path/to/root_fs eth0=mcast

       -net none
           Indicate that no network devices should be configured. It is used
           to override the default configuration (-net nic -net user) which is
           activated if no -net options are provided.

       -tftp dir
           When using the user mode network stack, activate a built-in TFTP
           server. The files in dir will be exposed as the root of a TFTP
           server.  The TFTP client on the guest must be configured in binary
           mode (use the command "bin" of the Unix TFTP client). The host IP
           address on the guest is as usual 10.0.2.2.

       -bootp file
           When using the user mode network stack, broadcast file as the BOOTP
           filename.  In conjunction with -tftp, this can be used to network
           boot a guest from a local directory.

           Example (using pxelinux):

                   qemu -hda linux.img -boot n -tftp /path/to/tftp/files -bootp /pxelinux.0

       -smb dir
           When using the user mode network stack, activate a built-in SMB
           server so that Windows OSes can access to the host files in dir
           transparently.

           In the guest Windows OS, the line:

                   10.0.2.4 smbserver

           must be added in the file C:\WINDOWS\LMHOSTS (for windows 9x/Me) or
           C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS (Windows NT/2000).

           Then dir can be accessed in \\smbserver\qemu.

           Note that a SAMBA server must be installed on the host OS in
           /usr/sbin/smbd. QEMU was tested successfully with smbd version
           2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core
           3.

       -redir [tcp|udp]:host-port:[guest-host]:guest-port
           When using the user mode network stack, redirect incoming TCP or
           UDP connections to the host port host-port to the guest guest-host
           on guest port guest-port. If guest-host is not specified, its value
           is 10.0.2.15 (default address given by the built-in DHCP server).

           For example, to redirect host X11 connection from screen 1 to guest
           screen 0, use the following:

                   # on the host
                   qemu -redir tcp:6001::6000 [...]
                   # this host xterm should open in the guest X11 server
                   xterm -display :1

           To redirect telnet connections from host port 5555 to telnet port
           on the guest, use the following:

                   # on the host
                   qemu -redir tcp:5555::23 [...]
                   telnet localhost 5555

           Then when you use on the host "telnet localhost 5555", you connect
           to the guest telnet server.

       Linux boot specific: When using these options, you can use a given
       Linux kernel without installing it in the disk image. It can be useful
       for easier testing of various kernels.

       -kernel bzImage
           Use bzImage as kernel image.

       -append cmdline
           Use cmdline as kernel command line

       -initrd file
           Use file as initial ram disk.

       Debug/Expert options:

       -serial dev
           Redirect the virtual serial port to host character device dev. The
           default device is "vc" in graphical mode and "stdio" in non graphi‐
           cal mode.

           This option can be used several times to simulate up to 4 serials
           ports.

           Use "-serial none" to disable all serial ports.

           Available character devices are:

           "vc[:WxH]"
               Virtual console. Optionally, a width and height can be given in
               pixel with

                       vc:800x600

               It is also possible to specify width or height in characters:

                       vc:80Cx24C

           "pty"
               [Linux only] Pseudo TTY (a new PTY is automatically allocated)

           "none"
               No device is allocated.

           "null"
               void device

           "/dev/XXX"
               [Linux only] Use host tty, e.g. /dev/ttyS0. The host serial
               port parameters are set according to the emulated ones.

           "/dev/parportN"
               [Linux only, parallel port only] Use host parallel port N. Cur‐
               rently SPP and EPP parallel port features can be used.

           "file:filename"
               Write output to filename. No character can be read.

           "stdio"
               [Unix only] standard input/output

           "pipe:filename"
               name pipe filename

           "COMn"
               [Windows only] Use host serial port n

           "udp:[remote_host]:remote_port[@[src_ip]:src_port]"
               This implements UDP Net Console.  When remote_host or src_ip
               are not specified they default to 0.0.0.0.  When not using a
               specified src_port a random port is automatically chosen.

               If you just want a simple readonly console you can use "netcat"
               or "nc", by starting qemu with: "-serial udp::4555" and nc as:
               "nc -u -l -p 4555". Any time qemu writes something to that port
               it will appear in the netconsole session.

               If you plan to send characters back via netconsole or you want
               to stop and start qemu a lot of times, you should have qemu use
               the same source port each time by using something like "-serial
               udp::4555@4556" to qemu. Another approach is to use a patched
               version of netcat which can listen to a TCP port and send and
               receive characters via udp.  If you have a patched version of
               netcat which activates telnet remote echo and single char
               transfer, then you can use the following options to step up a
               netcat redirector to allow telnet on port 5555 to access the
               qemu port.

               "Qemu Options:"
                   -serial udp::4555@4556

               "netcat options:"
                   -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T

               "telnet options:"
                   localhost 5555

           "tcp:[host]:port[,server][,nowait][,nodelay]"
               The TCP Net Console has two modes of operation.  It can send
               the serial I/O to a location or wait for a connection from a
               location.  By default the TCP Net Console is sent to host at
               the port.  If you use the server option QEMU will wait for a
               client socket application to connect to the port before contin‐
               uing, unless the "nowait" option was specified.  The "nodelay"
               option disables the Nagle buffering algorithm.  If host is
               omitted, 0.0.0.0 is assumed. Only one TCP connection at a time
               is accepted. You can use "telnet" to connect to the correspond‐
               ing character device.

               "Example to send tcp console to 192.168.0.2 port 4444"
                   -serial tcp:192.168.0.2:4444

               "Example to listen and wait on port 4444 for connection"
                   -serial tcp::4444,server

               "Example to not wait and listen on ip 192.168.0.100 port 4444"
                   -serial tcp:192.168.0.100:4444,server,nowait

           "telnet:host:port[,server][,nowait][,nodelay]"
               The telnet protocol is used instead of raw tcp sockets.  The
               options work the same as if you had specified "-serial tcp".
               The difference is that the port acts like a telnet server or
               client using telnet option negotiation.  This will also allow
               you to send the MAGIC_SYSRQ sequence if you use a telnet that
               supports sending the break sequence.  Typically in unix telnet
               you do it with Control-] and then type "send break" followed by
               pressing the enter key.

           "unix:path[,server][,nowait]"
               A unix domain socket is used instead of a tcp socket.  The
               option works the same as if you had specified "-serial tcp"
               except the unix domain socket path is used for connections.

           "mon:dev_string"
               This is a special option to allow the monitor to be multiplexed
               onto another serial port.  The monitor is accessed with key
               sequence of Control-a and then pressing c. See monitor access
               @ref{pcsys_keys} in the -nographic section for more keys.
               dev_string should be any one of the serial devices specified
               above.  An example to multiplex the monitor onto a telnet
               server listening on port 4444 would be:

               "-serial mon:telnet::4444,server,nowait"
           "braille"
               Braille device.  This will use BrlAPI to display the braille
               output on a real or fake device.

       -parallel dev
           Redirect the virtual parallel port to host device dev (same devices
           as the serial port). On Linux hosts, /dev/parportN can be used to
           use hardware devices connected on the corresponding host parallel
           port.

           This option can be used several times to simulate up to 3 parallel
           ports.

           Use "-parallel none" to disable all parallel ports.

       -monitor dev
           Redirect the monitor to host device dev (same devices as the serial
           port).  The default device is "vc" in graphical mode and "stdio" in
           non graphical mode.

       -echr numeric_ascii_value
           Change the escape character used for switching to the monitor when
           using monitor and serial sharing.  The default is 0x01 when using
           the "-nographic" option.  0x01 is equal to pressing "Control-a".
           You can select a different character from the ascii control keys
           where 1 through 26 map to Control-a through Control-z.  For
           instance you could use the either of the following to change the
           escape character to Control-t.

           "-echr 0x14"
           "-echr 20"
       -s  Wait gdb connection to port 1234.

       -p port
           Change gdb connection port.  port can be either a decimal number to
           specify a TCP port, or a host device (same devices as the serial
           port).

       -S  Do not start CPU at startup (you must type ’c’ in the monitor).

       -d  Output log in /tmp/qemu.log

       -hdachs c,h,s,[,t]
           Force hard disk 0 physical geometry (1 <= c <= 16383, 1 <= h <= 16,
           1 <= s <= 63) and optionally force the BIOS translation mode
           (t=none, lba or auto). Usually QEMU can guess all those parameters.
           This option is useful for old MS-DOS disk images.

       -L path
           Set the directory for the BIOS, VGA BIOS and keymaps.

       -std-vga
           Simulate a standard VGA card with Bochs VBE extensions (default is
           Cirrus Logic GD5446 PCI VGA). If your guest OS supports the VESA
           2.0 VBE extensions (e.g. Windows XP) and if you want to use high
           resolution modes (>= 1280x1024x16) then you should use this option.

       -no-acpi
           Disable ACPI (Advanced Configuration and Power Interface) support.
           Use it if your guest OS complains about ACPI problems (PC target
           machine only).

       -no-reboot
           Exit instead of rebooting.

       -loadvm file
           Start right away with a saved state ("loadvm" in monitor)

       -semihosting
           Enable semihosting syscall emulation (ARM and M68K target machines
           only).

           On ARM this implements the "Angel" interface.  On M68K this imple‐
           ments the "ColdFire GDB" interface used by libgloss.

           Note that this allows guest direct access to the host filesystem,
           so should only be used with trusted guest OS.

       During the graphical emulation, you can use the following keys:

       Ctrl-Alt-f
           Toggle full screen

       Ctrl-Alt-n
           Switch to virtual console ’n’. Standard console mappings are:

           1   Target system display

           2   Monitor

           3   Serial port

       Ctrl-Alt
           Toggle mouse and keyboard grab.

       In the virtual consoles, you can use Ctrl-Up, Ctrl-Down, Ctrl-PageUp
       and Ctrl-PageDown to move in the back log.

       During emulation, if you are using the -nographic option, use Ctrl-a h
       to get terminal commands:

       Ctrl-a h
           Print this help

       Ctrl-a x
           Exit emulator

       Ctrl-a s
           Save disk data back to file (if -snapshot)

       Ctrl-a t
           toggle console timestamps

       Ctrl-a b
           Send break (magic sysrq in Linux)

       Ctrl-a c
           Switch between console and monitor

       Ctrl-a Ctrl-a
           Send Ctrl-a

       The following options are specific to the PowerPC emulation:

       -g WxH[xDEPTH]
           Set the initial VGA graphic mode. The default is 800x600x15.

       The following options are specific to the Sparc32 emulation:

       -g WxHx[xDEPTH]
           Set the initial TCX graphic mode. The default is 1024x768x8, cur‐
           rently the only other possible mode is 1024x768x24.

       -prom-env string
           Set OpenBIOS variables in NVRAM, for example:

                   qemu-system-sparc -prom-env 'auto-boot?=false' \
                    -prom-env 'boot-device=sd(0,2,0):d' -prom-env 'boot-args=linux single'

       -M [SS-5|SS-10|SS-20|SS-600MP|SS-2|SS-1000|SS-2000]
           Set the emulated machine type. Default is SS-5.

SEE ALSO
       The HTML documentation of QEMU for more precise information and Linux
       user mode emulator invocation.

AUTHOR
       Fabrice Bellard



                                  2008-04-28                           QEMU(1)
Источник — «http://xgu.ru:81/wiki/man:orig:qemu»