1 \input texinfo @c -*- texinfo -*-
3 @setfilename qemu-doc.info
4 @settitle QEMU Emulator User Documentation
12 @center @titlefont{QEMU Emulator}
14 @center @titlefont{User Documentation}
26 * QEMU PC System emulator::
27 * QEMU System emulator for non PC targets::
28 * QEMU User space emulator::
29 * compilation:: Compilation from the sources
40 * intro_features:: Features
46 QEMU is a FAST! processor emulator using dynamic translation to
47 achieve good emulation speed.
49 QEMU has two operating modes:
54 Full system emulation. In this mode, QEMU emulates a full system (for
55 example a PC), including one or several processors and various
56 peripherals. It can be used to launch different Operating Systems
57 without rebooting the PC or to debug system code.
60 User mode emulation. In this mode, QEMU can launch
61 processes compiled for one CPU on another CPU. It can be used to
62 launch the Wine Windows API emulator (@url{http://www.winehq.org}) or
63 to ease cross-compilation and cross-debugging.
67 QEMU can run without an host kernel driver and yet gives acceptable
70 For system emulation, the following hardware targets are supported:
72 @item PC (x86 or x86_64 processor)
73 @item ISA PC (old style PC without PCI bus)
74 @item PREP (PowerPC processor)
75 @item G3 BW PowerMac (PowerPC processor)
76 @item Mac99 PowerMac (PowerPC processor, in progress)
77 @item Sun4m/Sun4c/Sun4d (32-bit Sparc processor)
78 @item Sun4u/Sun4v (64-bit Sparc processor, in progress)
79 @item Malta board (32-bit and 64-bit MIPS processors)
80 @item MIPS Magnum (64-bit MIPS processor)
81 @item ARM Integrator/CP (ARM)
82 @item ARM Versatile baseboard (ARM)
83 @item ARM RealView Emulation baseboard (ARM)
84 @item Spitz, Akita, Borzoi and Terrier PDAs (PXA270 processor)
85 @item Luminary Micro LM3S811EVB (ARM Cortex-M3)
86 @item Luminary Micro LM3S6965EVB (ARM Cortex-M3)
87 @item Freescale MCF5208EVB (ColdFire V2).
88 @item Arnewsh MCF5206 evaluation board (ColdFire V2).
89 @item Palm Tungsten|E PDA (OMAP310 processor)
90 @item N800 and N810 tablets (OMAP2420 processor)
91 @item MusicPal (MV88W8618 ARM processor)
94 For user emulation, x86, PowerPC, ARM, 32-bit MIPS, Sparc32/64 and ColdFire(m68k) CPUs are supported.
99 If you want to compile QEMU yourself, see @ref{compilation}.
102 * install_linux:: Linux
103 * install_windows:: Windows
104 * install_mac:: Macintosh
110 If a precompiled package is available for your distribution - you just
111 have to install it. Otherwise, see @ref{compilation}.
113 @node install_windows
116 Download the experimental binary installer at
117 @url{http://www.free.oszoo.org/@/download.html}.
122 Download the experimental binary installer at
123 @url{http://www.free.oszoo.org/@/download.html}.
125 @node QEMU PC System emulator
126 @chapter QEMU PC System emulator
129 * pcsys_introduction:: Introduction
130 * pcsys_quickstart:: Quick Start
131 * sec_invocation:: Invocation
133 * pcsys_monitor:: QEMU Monitor
134 * disk_images:: Disk Images
135 * pcsys_network:: Network emulation
136 * direct_linux_boot:: Direct Linux Boot
137 * pcsys_usb:: USB emulation
138 * vnc_security:: VNC security
139 * gdb_usage:: GDB usage
140 * pcsys_os_specific:: Target OS specific information
143 @node pcsys_introduction
144 @section Introduction
146 @c man begin DESCRIPTION
148 The QEMU PC System emulator simulates the
149 following peripherals:
153 i440FX host PCI bridge and PIIX3 PCI to ISA bridge
155 Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
156 extensions (hardware level, including all non standard modes).
158 PS/2 mouse and keyboard
160 2 PCI IDE interfaces with hard disk and CD-ROM support
164 PCI/ISA PCI network adapters
168 Creative SoundBlaster 16 sound card
170 ENSONIQ AudioPCI ES1370 sound card
172 Intel 82801AA AC97 Audio compatible sound card
174 Adlib(OPL2) - Yamaha YM3812 compatible chip
176 Gravis Ultrasound GF1 sound card
178 CS4231A compatible sound card
180 PCI UHCI USB controller and a virtual USB hub.
183 SMP is supported with up to 255 CPUs.
185 Note that adlib, ac97, gus and cs4231a are only available when QEMU
186 was configured with --audio-card-list option containing the name(s) of
189 QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
192 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
194 QEMU uses GUS emulation(GUSEMU32 @url{http://www.deinmeister.de/gusemu/})
195 by Tibor "TS" Schütz.
197 CS4231A is the chip used in Windows Sound System and GUSMAX products
201 @node pcsys_quickstart
204 Download and uncompress the linux image (@file{linux.img}) and type:
210 Linux should boot and give you a prompt.
216 @c man begin SYNOPSIS
217 usage: qemu [options] [@var{disk_image}]
222 @var{disk_image} is a raw hard disk image for IDE hard disk 0.
226 @item -M @var{machine}
227 Select the emulated @var{machine} (@code{-M ?} for list)
229 @item -fda @var{file}
230 @item -fdb @var{file}
231 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
232 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
234 @item -hda @var{file}
235 @item -hdb @var{file}
236 @item -hdc @var{file}
237 @item -hdd @var{file}
238 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
240 @item -cdrom @var{file}
241 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
242 @option{-cdrom} at the same time). You can use the host CD-ROM by
243 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
245 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
247 Define a new drive. Valid options are:
250 @item file=@var{file}
251 This option defines which disk image (@pxref{disk_images}) to use with
252 this drive. If the filename contains comma, you must double it
253 (for instance, "file=my,,file" to use file "my,file").
254 @item if=@var{interface}
255 This option defines on which type on interface the drive is connected.
256 Available types are: ide, scsi, sd, mtd, floppy, pflash.
257 @item bus=@var{bus},unit=@var{unit}
258 These options define where is connected the drive by defining the bus number and
260 @item index=@var{index}
261 This option defines where is connected the drive by using an index in the list
262 of available connectors of a given interface type.
263 @item media=@var{media}
264 This option defines the type of the media: disk or cdrom.
265 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
266 These options have the same definition as they have in @option{-hdachs}.
267 @item snapshot=@var{snapshot}
268 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
269 @item cache=@var{cache}
270 @var{cache} is "none", "writeback", or "writethrough" and controls how the host cache is used to access block data.
271 @item format=@var{format}
272 Specify which disk @var{format} will be used rather than detecting
273 the format. Can be used to specifiy format=raw to avoid interpreting
274 an untrusted format header.
275 @item boot=@var{boot}
276 @var{boot} if "on" enables extboot for a given drive so it can be used as a boot drive.
279 By default, writethrough caching is used for all block device. This means that
280 the host page cache will be used to read and write data but write notification
281 will be sent to the guest only when the data has been reported as written by
282 the storage subsystem.
284 Writeback caching will report data writes as completed as soon as the data is
285 present in the host page cache. This is safe as long as you trust your host.
286 If your host crashes or loses power, then the guest may experience data
287 corruption. When using the @option{-snapshot} option, writeback caching is
290 The host page can be avoided entirely with @option{cache=none}. This will
291 attempt to do disk IO directly to the guests memory. QEMU may still perform
292 an internal copy of the data.
294 Instead of @option{-cdrom} you can use:
296 qemu -drive file=file,index=2,media=cdrom
299 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
302 qemu -drive file=file,index=0,media=disk
303 qemu -drive file=file,index=1,media=disk
304 qemu -drive file=file,index=2,media=disk
305 qemu -drive file=file,index=3,media=disk
308 You can connect a CDROM to the slave of ide0:
310 qemu -drive file=file,if=ide,index=1,media=cdrom
313 If you don't specify the "file=" argument, you define an empty drive:
315 qemu -drive if=ide,index=1,media=cdrom
318 You can connect a SCSI disk with unit ID 6 on the bus #0:
320 qemu -drive file=file,if=scsi,bus=0,unit=6
323 To boot from a SCSI disk, one would use:
326 qemu -drive file=file,if=scsi,boot=on
329 Instead of @option{-fda}, @option{-fdb}, you can use:
331 qemu -drive file=file,index=0,if=floppy
332 qemu -drive file=file,index=1,if=floppy
335 By default, @var{interface} is "ide" and @var{index} is automatically
338 qemu -drive file=a -drive file=b"
345 @item -boot [a|c|d|n]
346 Boot on floppy (a), hard disk (c), CD-ROM (d), or Etherboot (n). Hard disk boot
350 Write to temporary files instead of disk image files. In this case,
351 the raw disk image you use is not written back. You can however force
352 the write back by pressing @key{C-a s} (@pxref{disk_images}).
355 Disable boot signature checking for floppy disks in Bochs BIOS. It may
356 be needed to boot from old floppy disks.
359 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
360 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
361 gigabytes respectively.
363 @item -cpu @var{model}
364 Select CPU model (-cpu ? for list and additional feature selection)
367 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
368 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
373 Will show the audio subsystem help: list of drivers, tunable
376 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
378 Enable audio and selected sound hardware. Use ? to print all
379 available sound hardware.
382 qemu -soundhw sb16,adlib hda
383 qemu -soundhw es1370 hda
384 qemu -soundhw ac97 hda
385 qemu -soundhw all hda
389 Note that Linux's i810_audio OSS kernel (for AC97) module might
390 require manually specifying clocking.
393 modprobe i810_audio clocking=48000
397 Set the real time clock to local time (the default is to UTC
398 time). This option is needed to have correct date in MS-DOS or
401 @item -startdate @var{date}
402 Set the initial date of the real time clock. Valid formats for
403 @var{date} are: @code{now} or @code{2006-06-17T16:01:21} or
404 @code{2006-06-17}. The default value is @code{now}.
406 @item -pidfile @var{file}
407 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
411 Daemonize the QEMU process after initialization. QEMU will not detach from
412 standard IO until it is ready to receive connections on any of its devices.
413 This option is a useful way for external programs to launch QEMU without having
414 to cope with initialization race conditions.
417 Use it when installing Windows 2000 to avoid a disk full bug. After
418 Windows 2000 is installed, you no longer need this option (this option
419 slows down the IDE transfers).
421 @item -option-rom @var{file}
422 Load the contents of @var{file} as an option ROM.
423 This option is useful to load things like EtherBoot.
425 @item -name @var{name}
426 Sets the @var{name} of the guest.
427 This name will be displayed in the SDL window caption.
428 The @var{name} will also be used for the VNC server.
437 Normally, QEMU uses SDL to display the VGA output. With this option,
438 you can totally disable graphical output so that QEMU is a simple
439 command line application. The emulated serial port is redirected on
440 the console. Therefore, you can still use QEMU to debug a Linux kernel
441 with a serial console.
445 Normally, QEMU uses SDL to display the VGA output. With this option,
446 QEMU can display the VGA output when in text mode using a
447 curses/ncurses interface. Nothing is displayed in graphical mode.
451 Do not use decorations for SDL windows and start them using the whole
452 available screen space. This makes the using QEMU in a dedicated desktop
453 workspace more convenient.
457 Disable SDL window close capability.
460 Start in full screen.
462 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
464 Normally, QEMU uses SDL to display the VGA output. With this option,
465 you can have QEMU listen on VNC display @var{display} and redirect the VGA
466 display over the VNC session. It is very useful to enable the usb
467 tablet device when using this option (option @option{-usbdevice
468 tablet}). When using the VNC display, you must use the @option{-k}
469 parameter to set the keyboard layout if you are not using en-us. Valid
470 syntax for the @var{display} is
474 @item @var{host}:@var{d}
476 TCP connections will only be allowed from @var{host} on display @var{d}.
477 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
478 be omitted in which case the server will accept connections from any host.
480 @item @code{unix}:@var{path}
482 Connections will be allowed over UNIX domain sockets where @var{path} is the
483 location of a unix socket to listen for connections on.
487 VNC is initialized but not started. The monitor @code{change} command
488 can be used to later start the VNC server.
492 Following the @var{display} value there may be one or more @var{option} flags
493 separated by commas. Valid options are
499 Connect to a listening VNC client via a ``reverse'' connection. The
500 client is specified by the @var{display}. For reverse network
501 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
502 is a TCP port number, not a display number.
506 Require that password based authentication is used for client connections.
507 The password must be set separately using the @code{change} command in the
512 Require that client use TLS when communicating with the VNC server. This
513 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
514 attack. It is recommended that this option be combined with either the
515 @var{x509} or @var{x509verify} options.
517 @item x509=@var{/path/to/certificate/dir}
519 Valid if @option{tls} is specified. Require that x509 credentials are used
520 for negotiating the TLS session. The server will send its x509 certificate
521 to the client. It is recommended that a password be set on the VNC server
522 to provide authentication of the client when this is used. The path following
523 this option specifies where the x509 certificates are to be loaded from.
524 See the @ref{vnc_security} section for details on generating certificates.
526 @item x509verify=@var{/path/to/certificate/dir}
528 Valid if @option{tls} is specified. Require that x509 credentials are used
529 for negotiating the TLS session. The server will send its x509 certificate
530 to the client, and request that the client send its own x509 certificate.
531 The server will validate the client's certificate against the CA certificate,
532 and reject clients when validation fails. If the certificate authority is
533 trusted, this is a sufficient authentication mechanism. You may still wish
534 to set a password on the VNC server as a second authentication layer. The
535 path following this option specifies where the x509 certificates are to
536 be loaded from. See the @ref{vnc_security} section for details on generating
541 @item -k @var{language}
543 Use keyboard layout @var{language} (for example @code{fr} for
544 French). This option is only needed where it is not easy to get raw PC
545 keycodes (e.g. on Macs, with some X11 servers or with a VNC
546 display). You don't normally need to use it on PC/Linux or PC/Windows
549 The available layouts are:
551 ar de-ch es fo fr-ca hu ja mk no pt-br sv
552 da en-gb et fr fr-ch is lt nl pl ru th
553 de en-us fi fr-be hr it lv nl-be pt sl tr
556 The default is @code{en-us}.
564 Enable the USB driver (will be the default soon)
566 @item -usbdevice @var{devname}
567 Add the USB device @var{devname}. @xref{usb_devices}.
572 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
575 Pointer device that uses absolute coordinates (like a touchscreen). This
576 means qemu is able to report the mouse position without having to grab the
577 mouse. Also overrides the PS/2 mouse emulation when activated.
579 @item disk:[format=@var{format}]:file
580 Mass storage device based on file. The optional @var{format} argument
581 will be used rather than detecting the format. Can be used to specifiy
582 format=raw to avoid interpreting an untrusted format header.
585 Pass through the host device identified by bus.addr (Linux only).
587 @item host:vendor_id:product_id
588 Pass through the host device identified by vendor_id:product_id (Linux only).
590 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
591 Serial converter to host character device @var{dev}, see @code{-serial} for the
595 Braille device. This will use BrlAPI to display the braille output on a real
599 Network adapter that supports CDC ethernet and RNDIS protocols.
609 @item -net nic[,vlan=@var{n}][,macaddr=@var{addr}][,model=@var{type}]
610 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
611 = 0 is the default). The NIC is an rtl8139 by default on the PC
612 target. Optionally, the MAC address can be changed. If no
613 @option{-net} option is specified, a single NIC is created.
614 Qemu can emulate several different models of network card.
615 Valid values for @var{type} are
616 @code{i82551}, @code{i82557b}, @code{i82559er},
617 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
618 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
619 Not all devices are supported on all targets. Use -net nic,model=?
620 for a list of available devices for your target.
622 @item -net user[,vlan=@var{n}][,hostname=@var{name}]
623 Use the user mode network stack which requires no administrator
624 privilege to run. @option{hostname=name} can be used to specify the client
625 hostname reported by the builtin DHCP server.
627 @item -net tap[,vlan=@var{n}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}]
628 Connect the host TAP network interface @var{name} to VLAN @var{n}, use
629 the network script @var{file} to configure it and the network script
630 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
631 automatically provides one. @option{fd}=@var{h} can be used to specify
632 the handle of an already opened host TAP interface. The default network
633 configure script is @file{/etc/qemu-ifup} and the default network
634 deconfigure script is @file{/etc/qemu-ifdown}. Use @option{script=no}
635 or @option{downscript=no} to disable script execution. Example:
638 qemu linux.img -net nic -net tap
641 More complicated example (two NICs, each one connected to a TAP device)
643 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
644 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
648 @item -net socket[,vlan=@var{n}][,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
650 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
651 machine using a TCP socket connection. If @option{listen} is
652 specified, QEMU waits for incoming connections on @var{port}
653 (@var{host} is optional). @option{connect} is used to connect to
654 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
655 specifies an already opened TCP socket.
659 # launch a first QEMU instance
660 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
661 -net socket,listen=:1234
662 # connect the VLAN 0 of this instance to the VLAN 0
663 # of the first instance
664 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
665 -net socket,connect=127.0.0.1:1234
668 @item -net socket[,vlan=@var{n}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}]
670 Create a VLAN @var{n} shared with another QEMU virtual
671 machines using a UDP multicast socket, effectively making a bus for
672 every QEMU with same multicast address @var{maddr} and @var{port}.
676 Several QEMU can be running on different hosts and share same bus (assuming
677 correct multicast setup for these hosts).
679 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
680 @url{http://user-mode-linux.sf.net}.
682 Use @option{fd=h} to specify an already opened UDP multicast socket.
687 # launch one QEMU instance
688 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
689 -net socket,mcast=230.0.0.1:1234
690 # launch another QEMU instance on same "bus"
691 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
692 -net socket,mcast=230.0.0.1:1234
693 # launch yet another QEMU instance on same "bus"
694 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
695 -net socket,mcast=230.0.0.1:1234
698 Example (User Mode Linux compat.):
700 # launch QEMU instance (note mcast address selected
702 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
703 -net socket,mcast=239.192.168.1:1102
705 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
708 @item -net vde[,vlan=@var{n}][,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
709 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
710 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
711 and MODE @var{octalmode} to change default ownership and permissions for
712 communication port. This option is available only if QEMU has been compiled
713 with vde support enabled.
718 vde_switch -F -sock /tmp/myswitch
719 # launch QEMU instance
720 qemu linux.img -net nic -net vde,sock=/tmp/myswitch
724 Indicate that no network devices should be configured. It is used to
725 override the default configuration (@option{-net nic -net user}) which
726 is activated if no @option{-net} options are provided.
728 @item -tftp @var{dir}
729 When using the user mode network stack, activate a built-in TFTP
730 server. The files in @var{dir} will be exposed as the root of a TFTP server.
731 The TFTP client on the guest must be configured in binary mode (use the command
732 @code{bin} of the Unix TFTP client). The host IP address on the guest is as
735 @item -bootp @var{file}
736 When using the user mode network stack, broadcast @var{file} as the BOOTP
737 filename. In conjunction with @option{-tftp}, this can be used to network boot
738 a guest from a local directory.
740 Example (using pxelinux):
742 qemu -hda linux.img -boot n -tftp /path/to/tftp/files -bootp /pxelinux.0
746 When using the user mode network stack, activate a built-in SMB
747 server so that Windows OSes can access to the host files in @file{@var{dir}}
750 In the guest Windows OS, the line:
754 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
755 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
757 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
759 Note that a SAMBA server must be installed on the host OS in
760 @file{/usr/sbin/smbd}. QEMU was tested successfully with smbd version
761 2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core 3.
763 @item -redir [tcp|udp]:@var{host-port}:[@var{guest-host}]:@var{guest-port}
765 When using the user mode network stack, redirect incoming TCP or UDP
766 connections to the host port @var{host-port} to the guest
767 @var{guest-host} on guest port @var{guest-port}. If @var{guest-host}
768 is not specified, its value is 10.0.2.15 (default address given by the
769 built-in DHCP server).
771 For example, to redirect host X11 connection from screen 1 to guest
772 screen 0, use the following:
776 qemu -redir tcp:6001::6000 [...]
777 # this host xterm should open in the guest X11 server
781 To redirect telnet connections from host port 5555 to telnet port on
782 the guest, use the following:
786 qemu -redir tcp:5555::23 [...]
787 telnet localhost 5555
790 Then when you use on the host @code{telnet localhost 5555}, you
791 connect to the guest telnet server.
795 Bluetooth(R) options:
799 Defines the function of the corresponding Bluetooth HCI. -bt options
800 are matched with the HCIs present in the chosen machine type. For
801 example when emulating a machine with only one HCI built into it, only
802 the first @code{-bt hci[...]} option is valid and defines the HCI's
803 logic. The Transport Layer is decided by the machine type. Currently
804 the machines @code{n800} and @code{n810} have one HCI and all other
808 The following three types are recognized:
812 (default) The corresponding Bluetooth HCI assumes no internal logic
813 and will not respond to any HCI commands or emit events.
815 @item -bt hci,host[:@var{id}]
816 (@code{bluez} only) The corresponding HCI passes commands / events
817 to / from the physical HCI identified by the name @var{id} (default:
818 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
819 capable systems like Linux.
821 @item -bt hci[,vlan=@var{n}]
822 Add a virtual, standard HCI that will participate in the Bluetooth
823 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
824 VLANs, devices inside a bluetooth network @var{n} can only communicate
825 with other devices in the same network (scatternet).
828 @item -bt vhci[,vlan=@var{n}]
829 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
830 to the host bluetooth stack instead of to the emulated target. This
831 allows the host and target machines to participate in a common scatternet
832 and communicate. Requires the Linux @code{vhci} driver installed. Can
833 be used as following:
836 qemu [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
839 @item -bt device:@var{dev}[,vlan=@var{n}]
840 Emulate a bluetooth device @var{dev} and place it in network @var{n}
841 (default @code{0}). QEMU can only emulate one type of bluetooth devices
846 Virtual wireless keyboard implementing the HIDP bluetooth profile.
851 Linux boot specific: When using these options, you can use a given
852 Linux kernel without installing it in the disk image. It can be useful
853 for easier testing of various kernels.
857 @item -kernel @var{bzImage}
858 Use @var{bzImage} as kernel image.
860 @item -append @var{cmdline}
861 Use @var{cmdline} as kernel command line
863 @item -initrd @var{file}
864 Use @var{file} as initial ram disk.
868 Debug/Expert options:
871 @item -serial @var{dev}
872 Redirect the virtual serial port to host character device
873 @var{dev}. The default device is @code{vc} in graphical mode and
874 @code{stdio} in non graphical mode.
876 This option can be used several times to simulate up to 4 serials
879 Use @code{-serial none} to disable all serial ports.
881 Available character devices are:
884 Virtual console. Optionally, a width and height can be given in pixel with
888 It is also possible to specify width or height in characters:
893 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
895 No device is allocated.
899 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
900 parameters are set according to the emulated ones.
901 @item /dev/parport@var{N}
902 [Linux only, parallel port only] Use host parallel port
903 @var{N}. Currently SPP and EPP parallel port features can be used.
904 @item file:@var{filename}
905 Write output to @var{filename}. No character can be read.
907 [Unix only] standard input/output
908 @item pipe:@var{filename}
909 name pipe @var{filename}
911 [Windows only] Use host serial port @var{n}
912 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
913 This implements UDP Net Console.
914 When @var{remote_host} or @var{src_ip} are not specified
915 they default to @code{0.0.0.0}.
916 When not using a specified @var{src_port} a random port is automatically chosen.
918 If you just want a simple readonly console you can use @code{netcat} or
919 @code{nc}, by starting qemu with: @code{-serial udp::4555} and nc as:
920 @code{nc -u -l -p 4555}. Any time qemu writes something to that port it
921 will appear in the netconsole session.
923 If you plan to send characters back via netconsole or you want to stop
924 and start qemu a lot of times, you should have qemu use the same
925 source port each time by using something like @code{-serial
926 udp::4555@@:4556} to qemu. Another approach is to use a patched
927 version of netcat which can listen to a TCP port and send and receive
928 characters via udp. If you have a patched version of netcat which
929 activates telnet remote echo and single char transfer, then you can
930 use the following options to step up a netcat redirector to allow
931 telnet on port 5555 to access the qemu port.
934 -serial udp::4555@@:4556
935 @item netcat options:
936 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
937 @item telnet options:
942 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
943 The TCP Net Console has two modes of operation. It can send the serial
944 I/O to a location or wait for a connection from a location. By default
945 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
946 the @var{server} option QEMU will wait for a client socket application
947 to connect to the port before continuing, unless the @code{nowait}
948 option was specified. The @code{nodelay} option disables the Nagle buffering
949 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
950 one TCP connection at a time is accepted. You can use @code{telnet} to
951 connect to the corresponding character device.
953 @item Example to send tcp console to 192.168.0.2 port 4444
954 -serial tcp:192.168.0.2:4444
955 @item Example to listen and wait on port 4444 for connection
956 -serial tcp::4444,server
957 @item Example to not wait and listen on ip 192.168.0.100 port 4444
958 -serial tcp:192.168.0.100:4444,server,nowait
961 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
962 The telnet protocol is used instead of raw tcp sockets. The options
963 work the same as if you had specified @code{-serial tcp}. The
964 difference is that the port acts like a telnet server or client using
965 telnet option negotiation. This will also allow you to send the
966 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
967 sequence. Typically in unix telnet you do it with Control-] and then
968 type "send break" followed by pressing the enter key.
970 @item unix:@var{path}[,server][,nowait]
971 A unix domain socket is used instead of a tcp socket. The option works the
972 same as if you had specified @code{-serial tcp} except the unix domain socket
973 @var{path} is used for connections.
975 @item mon:@var{dev_string}
976 This is a special option to allow the monitor to be multiplexed onto
977 another serial port. The monitor is accessed with key sequence of
978 @key{Control-a} and then pressing @key{c}. See monitor access
979 @ref{pcsys_keys} in the -nographic section for more keys.
980 @var{dev_string} should be any one of the serial devices specified
981 above. An example to multiplex the monitor onto a telnet server
982 listening on port 4444 would be:
984 @item -serial mon:telnet::4444,server,nowait
988 Braille device. This will use BrlAPI to display the braille output on a real
993 @item -parallel @var{dev}
994 Redirect the virtual parallel port to host device @var{dev} (same
995 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
996 be used to use hardware devices connected on the corresponding host
999 This option can be used several times to simulate up to 3 parallel
1002 Use @code{-parallel none} to disable all parallel ports.
1004 @item -monitor @var{dev}
1005 Redirect the monitor to host device @var{dev} (same devices as the
1007 The default device is @code{vc} in graphical mode and @code{stdio} in
1010 @item -echr numeric_ascii_value
1011 Change the escape character used for switching to the monitor when using
1012 monitor and serial sharing. The default is @code{0x01} when using the
1013 @code{-nographic} option. @code{0x01} is equal to pressing
1014 @code{Control-a}. You can select a different character from the ascii
1015 control keys where 1 through 26 map to Control-a through Control-z. For
1016 instance you could use the either of the following to change the escape
1017 character to Control-t.
1024 Wait gdb connection to port 1234 (@pxref{gdb_usage}).
1026 Change gdb connection port. @var{port} can be either a decimal number
1027 to specify a TCP port, or a host device (same devices as the serial port).
1029 Do not start CPU at startup (you must type 'c' in the monitor).
1031 Output log in /tmp/qemu.log
1032 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
1033 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
1034 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
1035 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
1036 all those parameters. This option is useful for old MS-DOS disk
1040 Set the directory for the BIOS, VGA BIOS and keymaps.
1042 @item -vga @var{type}
1043 Select type of VGA card to emulate. Valid values for @var{type} are
1046 Cirrus Logic GD5446 Video card. All Windows versions starting from
1047 Windows 95 should recognize and use this graphic card. For optimal
1048 performances, use 16 bit color depth in the guest and the host OS.
1049 (This one is the default)
1051 Standard VGA card with Bochs VBE extensions. If your guest OS
1052 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1053 to use high resolution modes (>= 1280x1024x16) then you should use
1056 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1057 recent XFree86/XOrg server or Windows guest with a driver for this
1062 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1063 it if your guest OS complains about ACPI problems (PC target machine
1067 Exit instead of rebooting.
1070 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
1071 This allows for instance switching to monitor to commit changes to the
1075 Start right away with a saved state (@code{loadvm} in monitor)
1078 Enable semihosting syscall emulation (ARM and M68K target machines only).
1080 On ARM this implements the "Angel" interface.
1081 On M68K this implements the "ColdFire GDB" interface used by libgloss.
1083 Note that this allows guest direct access to the host filesystem,
1084 so should only be used with trusted guest OS.
1086 @item -icount [N|auto]
1087 Enable virtual instruction counter. The virtual cpu will execute one
1088 instruction every 2^N ns of virtual time. If @code{auto} is specified
1089 then the virtual cpu speed will be automatically adjusted to keep virtual
1090 time within a few seconds of real time.
1092 Note that while this option can give deterministic behavior, it does not
1093 provide cycle accurate emulation. Modern CPUs contain superscalar out of
1094 order cores with complex cache hierarchies. The number of instructions
1095 executed often has little or no correlation with actual performance.
1103 @c man begin OPTIONS
1105 During the graphical emulation, you can use the following keys:
1111 Switch to virtual console 'n'. Standard console mappings are:
1114 Target system display
1122 Toggle mouse and keyboard grab.
1125 In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
1126 @key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
1128 During emulation, if you are using the @option{-nographic} option, use
1129 @key{Ctrl-a h} to get terminal commands:
1137 Save disk data back to file (if -snapshot)
1139 toggle console timestamps
1141 Send break (magic sysrq in Linux)
1143 Switch between console and monitor
1151 @c man begin SEEALSO
1152 The HTML documentation of QEMU for more precise information and Linux
1153 user mode emulator invocation.
1163 @section QEMU Monitor
1165 The QEMU monitor is used to give complex commands to the QEMU
1166 emulator. You can use it to:
1171 Remove or insert removable media images
1172 (such as CD-ROM or floppies).
1175 Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
1178 @item Inspect the VM state without an external debugger.
1182 @subsection Commands
1184 The following commands are available:
1188 @item help or ? [@var{cmd}]
1189 Show the help for all commands or just for command @var{cmd}.
1192 Commit changes to the disk images (if -snapshot is used).
1194 @item info @var{subcommand}
1195 Show various information about the system state.
1199 show the various VLANs and the associated devices
1201 show the block devices
1202 @item info registers
1203 show the cpu registers
1205 show the command line history
1207 show emulated PCI device
1209 show USB devices plugged on the virtual USB hub
1211 show all USB host devices
1213 show information about active capturing
1214 @item info snapshots
1215 show list of VM snapshots
1217 show which guest mouse is receiving events
1223 @item eject [-f] @var{device}
1224 Eject a removable medium (use -f to force it).
1226 @item change @var{device} @var{setting}
1228 Change the configuration of a device.
1231 @item change @var{diskdevice} @var{filename}
1232 Change the medium for a removable disk device to point to @var{filename}. eg
1235 (qemu) change ide1-cd0 /path/to/some.iso
1238 @item change vnc @var{display},@var{options}
1239 Change the configuration of the VNC server. The valid syntax for @var{display}
1240 and @var{options} are described at @ref{sec_invocation}. eg
1243 (qemu) change vnc localhost:1
1246 @item change vnc password
1248 Change the password associated with the VNC server. The monitor will prompt for
1249 the new password to be entered. VNC passwords are only significant upto 8 letters.
1253 (qemu) change vnc password
1259 @item screendump @var{filename}
1260 Save screen into PPM image @var{filename}.
1262 @item mouse_move @var{dx} @var{dy} [@var{dz}]
1263 Move the active mouse to the specified coordinates @var{dx} @var{dy}
1264 with optional scroll axis @var{dz}.
1266 @item mouse_button @var{val}
1267 Change the active mouse button state @var{val} (1=L, 2=M, 4=R).
1269 @item mouse_set @var{index}
1270 Set which mouse device receives events at given @var{index}, index
1271 can be obtained with
1276 @item wavcapture @var{filename} [@var{frequency} [@var{bits} [@var{channels}]]]
1277 Capture audio into @var{filename}. Using sample rate @var{frequency}
1278 bits per sample @var{bits} and number of channels @var{channels}.
1282 @item Sample rate = 44100 Hz - CD quality
1284 @item Number of channels = 2 - Stereo
1287 @item stopcapture @var{index}
1288 Stop capture with a given @var{index}, index can be obtained with
1293 @item log @var{item1}[,...]
1294 Activate logging of the specified items to @file{/tmp/qemu.log}.
1296 @item savevm [@var{tag}|@var{id}]
1297 Create a snapshot of the whole virtual machine. If @var{tag} is
1298 provided, it is used as human readable identifier. If there is already
1299 a snapshot with the same tag or ID, it is replaced. More info at
1302 @item loadvm @var{tag}|@var{id}
1303 Set the whole virtual machine to the snapshot identified by the tag
1304 @var{tag} or the unique snapshot ID @var{id}.
1306 @item delvm @var{tag}|@var{id}
1307 Delete the snapshot identified by @var{tag} or @var{id}.
1315 @item gdbserver [@var{port}]
1316 Start gdbserver session (default @var{port}=1234)
1318 @item x/fmt @var{addr}
1319 Virtual memory dump starting at @var{addr}.
1321 @item xp /@var{fmt} @var{addr}
1322 Physical memory dump starting at @var{addr}.
1324 @var{fmt} is a format which tells the command how to format the
1325 data. Its syntax is: @option{/@{count@}@{format@}@{size@}}
1329 is the number of items to be dumped.
1332 can be x (hex), d (signed decimal), u (unsigned decimal), o (octal),
1333 c (char) or i (asm instruction).
1336 can be b (8 bits), h (16 bits), w (32 bits) or g (64 bits). On x86,
1337 @code{h} or @code{w} can be specified with the @code{i} format to
1338 respectively select 16 or 32 bit code instruction size.
1345 Dump 10 instructions at the current instruction pointer:
1350 0x90107065: lea 0x0(%esi,1),%esi
1351 0x90107069: lea 0x0(%edi,1),%edi
1353 0x90107071: jmp 0x90107080
1361 Dump 80 16 bit values at the start of the video memory.
1363 (qemu) xp/80hx 0xb8000
1364 0x000b8000: 0x0b50 0x0b6c 0x0b65 0x0b78 0x0b38 0x0b36 0x0b2f 0x0b42
1365 0x000b8010: 0x0b6f 0x0b63 0x0b68 0x0b73 0x0b20 0x0b56 0x0b47 0x0b41
1366 0x000b8020: 0x0b42 0x0b69 0x0b6f 0x0b73 0x0b20 0x0b63 0x0b75 0x0b72
1367 0x000b8030: 0x0b72 0x0b65 0x0b6e 0x0b74 0x0b2d 0x0b63 0x0b76 0x0b73
1368 0x000b8040: 0x0b20 0x0b30 0x0b35 0x0b20 0x0b4e 0x0b6f 0x0b76 0x0b20
1369 0x000b8050: 0x0b32 0x0b30 0x0b30 0x0b33 0x0720 0x0720 0x0720 0x0720
1370 0x000b8060: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1371 0x000b8070: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1372 0x000b8080: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1373 0x000b8090: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1377 @item p or print/@var{fmt} @var{expr}
1379 Print expression value. Only the @var{format} part of @var{fmt} is
1382 @item sendkey @var{keys}
1384 Send @var{keys} to the emulator. @var{keys} could be the name of the
1385 key or @code{#} followed by the raw value in either decimal or hexadecimal
1386 format. Use @code{-} to press several keys simultaneously. Example:
1391 This command is useful to send keys that your graphical user interface
1392 intercepts at low level, such as @code{ctrl-alt-f1} in X Window.
1398 @item boot_set @var{bootdevicelist}
1400 Define new values for the boot device list. Those values will override
1401 the values specified on the command line through the @code{-boot} option.
1403 The values that can be specified here depend on the machine type, but are
1404 the same that can be specified in the @code{-boot} command line option.
1406 @item usb_add @var{devname}
1408 Add the USB device @var{devname}. For details of available devices see
1411 @item usb_del @var{devname}
1413 Remove the USB device @var{devname} from the QEMU virtual USB
1414 hub. @var{devname} has the syntax @code{bus.addr}. Use the monitor
1415 command @code{info usb} to see the devices you can remove.
1419 @subsection Integer expressions
1421 The monitor understands integers expressions for every integer
1422 argument. You can use register names to get the value of specifics
1423 CPU registers by prefixing them with @emph{$}.
1426 @section Disk Images
1428 Since version 0.6.1, QEMU supports many disk image formats, including
1429 growable disk images (their size increase as non empty sectors are
1430 written), compressed and encrypted disk images. Version 0.8.3 added
1431 the new qcow2 disk image format which is essential to support VM
1435 * disk_images_quickstart:: Quick start for disk image creation
1436 * disk_images_snapshot_mode:: Snapshot mode
1437 * vm_snapshots:: VM snapshots
1438 * qemu_img_invocation:: qemu-img Invocation
1439 * qemu_nbd_invocation:: qemu-nbd Invocation
1440 * host_drives:: Using host drives
1441 * disk_images_fat_images:: Virtual FAT disk images
1442 * disk_images_nbd:: NBD access
1445 @node disk_images_quickstart
1446 @subsection Quick start for disk image creation
1448 You can create a disk image with the command:
1450 qemu-img create myimage.img mysize
1452 where @var{myimage.img} is the disk image filename and @var{mysize} is its
1453 size in kilobytes. You can add an @code{M} suffix to give the size in
1454 megabytes and a @code{G} suffix for gigabytes.
1456 See @ref{qemu_img_invocation} for more information.
1458 @node disk_images_snapshot_mode
1459 @subsection Snapshot mode
1461 If you use the option @option{-snapshot}, all disk images are
1462 considered as read only. When sectors in written, they are written in
1463 a temporary file created in @file{/tmp}. You can however force the
1464 write back to the raw disk images by using the @code{commit} monitor
1465 command (or @key{C-a s} in the serial console).
1468 @subsection VM snapshots
1470 VM snapshots are snapshots of the complete virtual machine including
1471 CPU state, RAM, device state and the content of all the writable
1472 disks. In order to use VM snapshots, you must have at least one non
1473 removable and writable block device using the @code{qcow2} disk image
1474 format. Normally this device is the first virtual hard drive.
1476 Use the monitor command @code{savevm} to create a new VM snapshot or
1477 replace an existing one. A human readable name can be assigned to each
1478 snapshot in addition to its numerical ID.
1480 Use @code{loadvm} to restore a VM snapshot and @code{delvm} to remove
1481 a VM snapshot. @code{info snapshots} lists the available snapshots
1482 with their associated information:
1485 (qemu) info snapshots
1486 Snapshot devices: hda
1487 Snapshot list (from hda):
1488 ID TAG VM SIZE DATE VM CLOCK
1489 1 start 41M 2006-08-06 12:38:02 00:00:14.954
1490 2 40M 2006-08-06 12:43:29 00:00:18.633
1491 3 msys 40M 2006-08-06 12:44:04 00:00:23.514
1494 A VM snapshot is made of a VM state info (its size is shown in
1495 @code{info snapshots}) and a snapshot of every writable disk image.
1496 The VM state info is stored in the first @code{qcow2} non removable
1497 and writable block device. The disk image snapshots are stored in
1498 every disk image. The size of a snapshot in a disk image is difficult
1499 to evaluate and is not shown by @code{info snapshots} because the
1500 associated disk sectors are shared among all the snapshots to save
1501 disk space (otherwise each snapshot would need a full copy of all the
1504 When using the (unrelated) @code{-snapshot} option
1505 (@ref{disk_images_snapshot_mode}), you can always make VM snapshots,
1506 but they are deleted as soon as you exit QEMU.
1508 VM snapshots currently have the following known limitations:
1511 They cannot cope with removable devices if they are removed or
1512 inserted after a snapshot is done.
1514 A few device drivers still have incomplete snapshot support so their
1515 state is not saved or restored properly (in particular USB).
1518 @node qemu_img_invocation
1519 @subsection @code{qemu-img} Invocation
1521 @include qemu-img.texi
1523 @node qemu_nbd_invocation
1524 @subsection @code{qemu-nbd} Invocation
1526 @include qemu-nbd.texi
1529 @subsection Using host drives
1531 In addition to disk image files, QEMU can directly access host
1532 devices. We describe here the usage for QEMU version >= 0.8.3.
1534 @subsubsection Linux
1536 On Linux, you can directly use the host device filename instead of a
1537 disk image filename provided you have enough privileges to access
1538 it. For example, use @file{/dev/cdrom} to access to the CDROM or
1539 @file{/dev/fd0} for the floppy.
1543 You can specify a CDROM device even if no CDROM is loaded. QEMU has
1544 specific code to detect CDROM insertion or removal. CDROM ejection by
1545 the guest OS is supported. Currently only data CDs are supported.
1547 You can specify a floppy device even if no floppy is loaded. Floppy
1548 removal is currently not detected accurately (if you change floppy
1549 without doing floppy access while the floppy is not loaded, the guest
1550 OS will think that the same floppy is loaded).
1552 Hard disks can be used. Normally you must specify the whole disk
1553 (@file{/dev/hdb} instead of @file{/dev/hdb1}) so that the guest OS can
1554 see it as a partitioned disk. WARNING: unless you know what you do, it
1555 is better to only make READ-ONLY accesses to the hard disk otherwise
1556 you may corrupt your host data (use the @option{-snapshot} command
1557 line option or modify the device permissions accordingly).
1560 @subsubsection Windows
1564 The preferred syntax is the drive letter (e.g. @file{d:}). The
1565 alternate syntax @file{\\.\d:} is supported. @file{/dev/cdrom} is
1566 supported as an alias to the first CDROM drive.
1568 Currently there is no specific code to handle removable media, so it
1569 is better to use the @code{change} or @code{eject} monitor commands to
1570 change or eject media.
1572 Hard disks can be used with the syntax: @file{\\.\PhysicalDrive@var{N}}
1573 where @var{N} is the drive number (0 is the first hard disk).
1575 WARNING: unless you know what you do, it is better to only make
1576 READ-ONLY accesses to the hard disk otherwise you may corrupt your
1577 host data (use the @option{-snapshot} command line so that the
1578 modifications are written in a temporary file).
1582 @subsubsection Mac OS X
1584 @file{/dev/cdrom} is an alias to the first CDROM.
1586 Currently there is no specific code to handle removable media, so it
1587 is better to use the @code{change} or @code{eject} monitor commands to
1588 change or eject media.
1590 @node disk_images_fat_images
1591 @subsection Virtual FAT disk images
1593 QEMU can automatically create a virtual FAT disk image from a
1594 directory tree. In order to use it, just type:
1597 qemu linux.img -hdb fat:/my_directory
1600 Then you access access to all the files in the @file{/my_directory}
1601 directory without having to copy them in a disk image or to export
1602 them via SAMBA or NFS. The default access is @emph{read-only}.
1604 Floppies can be emulated with the @code{:floppy:} option:
1607 qemu linux.img -fda fat:floppy:/my_directory
1610 A read/write support is available for testing (beta stage) with the
1614 qemu linux.img -fda fat:floppy:rw:/my_directory
1617 What you should @emph{never} do:
1619 @item use non-ASCII filenames ;
1620 @item use "-snapshot" together with ":rw:" ;
1621 @item expect it to work when loadvm'ing ;
1622 @item write to the FAT directory on the host system while accessing it with the guest system.
1625 @node disk_images_nbd
1626 @subsection NBD access
1628 QEMU can access directly to block device exported using the Network Block Device
1632 qemu linux.img -hdb nbd:my_nbd_server.mydomain.org:1024
1635 If the NBD server is located on the same host, you can use an unix socket instead
1639 qemu linux.img -hdb nbd:unix:/tmp/my_socket
1642 In this case, the block device must be exported using qemu-nbd:
1645 qemu-nbd --socket=/tmp/my_socket my_disk.qcow2
1648 The use of qemu-nbd allows to share a disk between several guests:
1650 qemu-nbd --socket=/tmp/my_socket --share=2 my_disk.qcow2
1653 and then you can use it with two guests:
1655 qemu linux1.img -hdb nbd:unix:/tmp/my_socket
1656 qemu linux2.img -hdb nbd:unix:/tmp/my_socket
1660 @section Network emulation
1662 QEMU can simulate several network cards (PCI or ISA cards on the PC
1663 target) and can connect them to an arbitrary number of Virtual Local
1664 Area Networks (VLANs). Host TAP devices can be connected to any QEMU
1665 VLAN. VLAN can be connected between separate instances of QEMU to
1666 simulate large networks. For simpler usage, a non privileged user mode
1667 network stack can replace the TAP device to have a basic network
1672 QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
1673 connection between several network devices. These devices can be for
1674 example QEMU virtual Ethernet cards or virtual Host ethernet devices
1677 @subsection Using TAP network interfaces
1679 This is the standard way to connect QEMU to a real network. QEMU adds
1680 a virtual network device on your host (called @code{tapN}), and you
1681 can then configure it as if it was a real ethernet card.
1683 @subsubsection Linux host
1685 As an example, you can download the @file{linux-test-xxx.tar.gz}
1686 archive and copy the script @file{qemu-ifup} in @file{/etc} and
1687 configure properly @code{sudo} so that the command @code{ifconfig}
1688 contained in @file{qemu-ifup} can be executed as root. You must verify
1689 that your host kernel supports the TAP network interfaces: the
1690 device @file{/dev/net/tun} must be present.
1692 See @ref{sec_invocation} to have examples of command lines using the
1693 TAP network interfaces.
1695 @subsubsection Windows host
1697 There is a virtual ethernet driver for Windows 2000/XP systems, called
1698 TAP-Win32. But it is not included in standard QEMU for Windows,
1699 so you will need to get it separately. It is part of OpenVPN package,
1700 so download OpenVPN from : @url{http://openvpn.net/}.
1702 @subsection Using the user mode network stack
1704 By using the option @option{-net user} (default configuration if no
1705 @option{-net} option is specified), QEMU uses a completely user mode
1706 network stack (you don't need root privilege to use the virtual
1707 network). The virtual network configuration is the following:
1711 QEMU VLAN <------> Firewall/DHCP server <-----> Internet
1714 ----> DNS server (10.0.2.3)
1716 ----> SMB server (10.0.2.4)
1719 The QEMU VM behaves as if it was behind a firewall which blocks all
1720 incoming connections. You can use a DHCP client to automatically
1721 configure the network in the QEMU VM. The DHCP server assign addresses
1722 to the hosts starting from 10.0.2.15.
1724 In order to check that the user mode network is working, you can ping
1725 the address 10.0.2.2 and verify that you got an address in the range
1726 10.0.2.x from the QEMU virtual DHCP server.
1728 Note that @code{ping} is not supported reliably to the internet as it
1729 would require root privileges. It means you can only ping the local
1732 When using the built-in TFTP server, the router is also the TFTP
1735 When using the @option{-redir} option, TCP or UDP connections can be
1736 redirected from the host to the guest. It allows for example to
1737 redirect X11, telnet or SSH connections.
1739 @subsection Connecting VLANs between QEMU instances
1741 Using the @option{-net socket} option, it is possible to make VLANs
1742 that span several QEMU instances. See @ref{sec_invocation} to have a
1745 @node direct_linux_boot
1746 @section Direct Linux Boot
1748 This section explains how to launch a Linux kernel inside QEMU without
1749 having to make a full bootable image. It is very useful for fast Linux
1754 qemu -kernel arch/i386/boot/bzImage -hda root-2.4.20.img -append "root=/dev/hda"
1757 Use @option{-kernel} to provide the Linux kernel image and
1758 @option{-append} to give the kernel command line arguments. The
1759 @option{-initrd} option can be used to provide an INITRD image.
1761 When using the direct Linux boot, a disk image for the first hard disk
1762 @file{hda} is required because its boot sector is used to launch the
1765 If you do not need graphical output, you can disable it and redirect
1766 the virtual serial port and the QEMU monitor to the console with the
1767 @option{-nographic} option. The typical command line is:
1769 qemu -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1770 -append "root=/dev/hda console=ttyS0" -nographic
1773 Use @key{Ctrl-a c} to switch between the serial console and the
1774 monitor (@pxref{pcsys_keys}).
1777 @section USB emulation
1779 QEMU emulates a PCI UHCI USB controller. You can virtually plug
1780 virtual USB devices or real host USB devices (experimental, works only
1781 on Linux hosts). Qemu will automatically create and connect virtual USB hubs
1782 as necessary to connect multiple USB devices.
1786 * host_usb_devices::
1789 @subsection Connecting USB devices
1791 USB devices can be connected with the @option{-usbdevice} commandline option
1792 or the @code{usb_add} monitor command. Available devices are:
1796 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1798 Pointer device that uses absolute coordinates (like a touchscreen).
1799 This means qemu is able to report the mouse position without having
1800 to grab the mouse. Also overrides the PS/2 mouse emulation when activated.
1801 @item disk:@var{file}
1802 Mass storage device based on @var{file} (@pxref{disk_images})
1803 @item host:@var{bus.addr}
1804 Pass through the host device identified by @var{bus.addr}
1806 @item host:@var{vendor_id:product_id}
1807 Pass through the host device identified by @var{vendor_id:product_id}
1810 Virtual Wacom PenPartner tablet. This device is similar to the @code{tablet}
1811 above but it can be used with the tslib library because in addition to touch
1812 coordinates it reports touch pressure.
1814 Standard USB keyboard. Will override the PS/2 keyboard (if present).
1815 @item serial:[vendorid=@var{vendor_id}][,product_id=@var{product_id}]:@var{dev}
1816 Serial converter. This emulates an FTDI FT232BM chip connected to host character
1817 device @var{dev}. The available character devices are the same as for the
1818 @code{-serial} option. The @code{vendorid} and @code{productid} options can be
1819 used to override the default 0403:6001. For instance,
1821 usb_add serial:productid=FA00:tcp:192.168.0.2:4444
1823 will connect to tcp port 4444 of ip 192.168.0.2, and plug that to the virtual
1824 serial converter, faking a Matrix Orbital LCD Display (USB ID 0403:FA00).
1826 Braille device. This will use BrlAPI to display the braille output on a real
1828 @item net:@var{options}
1829 Network adapter that supports CDC ethernet and RNDIS protocols. @var{options}
1830 specifies NIC options as with @code{-net nic,}@var{options} (see description).
1831 For instance, user-mode networking can be used with
1833 qemu [...OPTIONS...] -net user,vlan=0 -usbdevice net:vlan=0
1835 Currently this cannot be used in machines that support PCI NICs.
1836 @item bt[:@var{hci-type}]
1837 Bluetooth dongle whose type is specified in the same format as with
1838 the @option{-bt hci} option, @pxref{bt-hcis,,allowed HCI types}. If
1839 no type is given, the HCI logic corresponds to @code{-bt hci,vlan=0}.
1840 This USB device implements the USB Transport Layer of HCI. Example
1843 qemu [...OPTIONS...] -usbdevice bt:hci,vlan=3 -bt device:keyboard,vlan=3
1847 @node host_usb_devices
1848 @subsection Using host USB devices on a Linux host
1850 WARNING: this is an experimental feature. QEMU will slow down when
1851 using it. USB devices requiring real time streaming (i.e. USB Video
1852 Cameras) are not supported yet.
1855 @item If you use an early Linux 2.4 kernel, verify that no Linux driver
1856 is actually using the USB device. A simple way to do that is simply to
1857 disable the corresponding kernel module by renaming it from @file{mydriver.o}
1858 to @file{mydriver.o.disabled}.
1860 @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
1866 @item Since only root can access to the USB devices directly, you can either launch QEMU as root or change the permissions of the USB devices you want to use. For testing, the following suffices:
1868 chown -R myuid /proc/bus/usb
1871 @item Launch QEMU and do in the monitor:
1874 Device 1.2, speed 480 Mb/s
1875 Class 00: USB device 1234:5678, USB DISK
1877 You should see the list of the devices you can use (Never try to use
1878 hubs, it won't work).
1880 @item Add the device in QEMU by using:
1882 usb_add host:1234:5678
1885 Normally the guest OS should report that a new USB device is
1886 plugged. You can use the option @option{-usbdevice} to do the same.
1888 @item Now you can try to use the host USB device in QEMU.
1892 When relaunching QEMU, you may have to unplug and plug again the USB
1893 device to make it work again (this is a bug).
1896 @section VNC security
1898 The VNC server capability provides access to the graphical console
1899 of the guest VM across the network. This has a number of security
1900 considerations depending on the deployment scenarios.
1904 * vnc_sec_password::
1905 * vnc_sec_certificate::
1906 * vnc_sec_certificate_verify::
1907 * vnc_sec_certificate_pw::
1908 * vnc_generate_cert::
1911 @subsection Without passwords
1913 The simplest VNC server setup does not include any form of authentication.
1914 For this setup it is recommended to restrict it to listen on a UNIX domain
1915 socket only. For example
1918 qemu [...OPTIONS...] -vnc unix:/home/joebloggs/.qemu-myvm-vnc
1921 This ensures that only users on local box with read/write access to that
1922 path can access the VNC server. To securely access the VNC server from a
1923 remote machine, a combination of netcat+ssh can be used to provide a secure
1926 @node vnc_sec_password
1927 @subsection With passwords
1929 The VNC protocol has limited support for password based authentication. Since
1930 the protocol limits passwords to 8 characters it should not be considered
1931 to provide high security. The password can be fairly easily brute-forced by
1932 a client making repeat connections. For this reason, a VNC server using password
1933 authentication should be restricted to only listen on the loopback interface
1934 or UNIX domain sockets. Password authentication is requested with the @code{password}
1935 option, and then once QEMU is running the password is set with the monitor. Until
1936 the monitor is used to set the password all clients will be rejected.
1939 qemu [...OPTIONS...] -vnc :1,password -monitor stdio
1940 (qemu) change vnc password
1945 @node vnc_sec_certificate
1946 @subsection With x509 certificates
1948 The QEMU VNC server also implements the VeNCrypt extension allowing use of
1949 TLS for encryption of the session, and x509 certificates for authentication.
1950 The use of x509 certificates is strongly recommended, because TLS on its
1951 own is susceptible to man-in-the-middle attacks. Basic x509 certificate
1952 support provides a secure session, but no authentication. This allows any
1953 client to connect, and provides an encrypted session.
1956 qemu [...OPTIONS...] -vnc :1,tls,x509=/etc/pki/qemu -monitor stdio
1959 In the above example @code{/etc/pki/qemu} should contain at least three files,
1960 @code{ca-cert.pem}, @code{server-cert.pem} and @code{server-key.pem}. Unprivileged
1961 users will want to use a private directory, for example @code{$HOME/.pki/qemu}.
1962 NB the @code{server-key.pem} file should be protected with file mode 0600 to
1963 only be readable by the user owning it.
1965 @node vnc_sec_certificate_verify
1966 @subsection With x509 certificates and client verification
1968 Certificates can also provide a means to authenticate the client connecting.
1969 The server will request that the client provide a certificate, which it will
1970 then validate against the CA certificate. This is a good choice if deploying
1971 in an environment with a private internal certificate authority.
1974 qemu [...OPTIONS...] -vnc :1,tls,x509verify=/etc/pki/qemu -monitor stdio
1978 @node vnc_sec_certificate_pw
1979 @subsection With x509 certificates, client verification and passwords
1981 Finally, the previous method can be combined with VNC password authentication
1982 to provide two layers of authentication for clients.
1985 qemu [...OPTIONS...] -vnc :1,password,tls,x509verify=/etc/pki/qemu -monitor stdio
1986 (qemu) change vnc password
1991 @node vnc_generate_cert
1992 @subsection Generating certificates for VNC
1994 The GNU TLS packages provides a command called @code{certtool} which can
1995 be used to generate certificates and keys in PEM format. At a minimum it
1996 is neccessary to setup a certificate authority, and issue certificates to
1997 each server. If using certificates for authentication, then each client
1998 will also need to be issued a certificate. The recommendation is for the
1999 server to keep its certificates in either @code{/etc/pki/qemu} or for
2000 unprivileged users in @code{$HOME/.pki/qemu}.
2004 * vnc_generate_server::
2005 * vnc_generate_client::
2007 @node vnc_generate_ca
2008 @subsubsection Setup the Certificate Authority
2010 This step only needs to be performed once per organization / organizational
2011 unit. First the CA needs a private key. This key must be kept VERY secret
2012 and secure. If this key is compromised the entire trust chain of the certificates
2013 issued with it is lost.
2016 # certtool --generate-privkey > ca-key.pem
2019 A CA needs to have a public certificate. For simplicity it can be a self-signed
2020 certificate, or one issue by a commercial certificate issuing authority. To
2021 generate a self-signed certificate requires one core piece of information, the
2022 name of the organization.
2025 # cat > ca.info <<EOF
2026 cn = Name of your organization
2030 # certtool --generate-self-signed \
2031 --load-privkey ca-key.pem
2032 --template ca.info \
2033 --outfile ca-cert.pem
2036 The @code{ca-cert.pem} file should be copied to all servers and clients wishing to utilize
2037 TLS support in the VNC server. The @code{ca-key.pem} must not be disclosed/copied at all.
2039 @node vnc_generate_server
2040 @subsubsection Issuing server certificates
2042 Each server (or host) needs to be issued with a key and certificate. When connecting
2043 the certificate is sent to the client which validates it against the CA certificate.
2044 The core piece of information for a server certificate is the hostname. This should
2045 be the fully qualified hostname that the client will connect with, since the client
2046 will typically also verify the hostname in the certificate. On the host holding the
2047 secure CA private key:
2050 # cat > server.info <<EOF
2051 organization = Name of your organization
2052 cn = server.foo.example.com
2057 # certtool --generate-privkey > server-key.pem
2058 # certtool --generate-certificate \
2059 --load-ca-certificate ca-cert.pem \
2060 --load-ca-privkey ca-key.pem \
2061 --load-privkey server server-key.pem \
2062 --template server.info \
2063 --outfile server-cert.pem
2066 The @code{server-key.pem} and @code{server-cert.pem} files should now be securely copied
2067 to the server for which they were generated. The @code{server-key.pem} is security
2068 sensitive and should be kept protected with file mode 0600 to prevent disclosure.
2070 @node vnc_generate_client
2071 @subsubsection Issuing client certificates
2073 If the QEMU VNC server is to use the @code{x509verify} option to validate client
2074 certificates as its authentication mechanism, each client also needs to be issued
2075 a certificate. The client certificate contains enough metadata to uniquely identify
2076 the client, typically organization, state, city, building, etc. On the host holding
2077 the secure CA private key:
2080 # cat > client.info <<EOF
2084 organiazation = Name of your organization
2085 cn = client.foo.example.com
2090 # certtool --generate-privkey > client-key.pem
2091 # certtool --generate-certificate \
2092 --load-ca-certificate ca-cert.pem \
2093 --load-ca-privkey ca-key.pem \
2094 --load-privkey client-key.pem \
2095 --template client.info \
2096 --outfile client-cert.pem
2099 The @code{client-key.pem} and @code{client-cert.pem} files should now be securely
2100 copied to the client for which they were generated.
2105 QEMU has a primitive support to work with gdb, so that you can do
2106 'Ctrl-C' while the virtual machine is running and inspect its state.
2108 In order to use gdb, launch qemu with the '-s' option. It will wait for a
2111 > qemu -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
2112 -append "root=/dev/hda"
2113 Connected to host network interface: tun0
2114 Waiting gdb connection on port 1234
2117 Then launch gdb on the 'vmlinux' executable:
2122 In gdb, connect to QEMU:
2124 (gdb) target remote localhost:1234
2127 Then you can use gdb normally. For example, type 'c' to launch the kernel:
2132 Here are some useful tips in order to use gdb on system code:
2136 Use @code{info reg} to display all the CPU registers.
2138 Use @code{x/10i $eip} to display the code at the PC position.
2140 Use @code{set architecture i8086} to dump 16 bit code. Then use
2141 @code{x/10i $cs*16+$eip} to dump the code at the PC position.
2144 Advanced debugging options:
2146 The default single stepping behavior is step with the IRQs and timer service routines off. It is set this way because when gdb executes a single step it expects to advance beyond the current instruction. With the IRQs and and timer service routines on, a single step might jump into the one of the interrupt or exception vectors instead of executing the current instruction. This means you may hit the same breakpoint a number of times before executing the instruction gdb wants to have executed. Because there are rare circumstances where you want to single step into an interrupt vector the behavior can be controlled from GDB. There are three commands you can query and set the single step behavior:
2148 @item maintenance packet qqemu.sstepbits
2150 This will display the MASK bits used to control the single stepping IE:
2152 (gdb) maintenance packet qqemu.sstepbits
2153 sending: "qqemu.sstepbits"
2154 received: "ENABLE=1,NOIRQ=2,NOTIMER=4"
2156 @item maintenance packet qqemu.sstep
2158 This will display the current value of the mask used when single stepping IE:
2160 (gdb) maintenance packet qqemu.sstep
2161 sending: "qqemu.sstep"
2164 @item maintenance packet Qqemu.sstep=HEX_VALUE
2166 This will change the single step mask, so if wanted to enable IRQs on the single step, but not timers, you would use:
2168 (gdb) maintenance packet Qqemu.sstep=0x5
2169 sending: "qemu.sstep=0x5"
2174 @node pcsys_os_specific
2175 @section Target OS specific information
2179 To have access to SVGA graphic modes under X11, use the @code{vesa} or
2180 the @code{cirrus} X11 driver. For optimal performances, use 16 bit
2181 color depth in the guest and the host OS.
2183 When using a 2.6 guest Linux kernel, you should add the option
2184 @code{clock=pit} on the kernel command line because the 2.6 Linux
2185 kernels make very strict real time clock checks by default that QEMU
2186 cannot simulate exactly.
2188 When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
2189 not activated because QEMU is slower with this patch. The QEMU
2190 Accelerator Module is also much slower in this case. Earlier Fedora
2191 Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporate this
2192 patch by default. Newer kernels don't have it.
2196 If you have a slow host, using Windows 95 is better as it gives the
2197 best speed. Windows 2000 is also a good choice.
2199 @subsubsection SVGA graphic modes support
2201 QEMU emulates a Cirrus Logic GD5446 Video
2202 card. All Windows versions starting from Windows 95 should recognize
2203 and use this graphic card. For optimal performances, use 16 bit color
2204 depth in the guest and the host OS.
2206 If you are using Windows XP as guest OS and if you want to use high
2207 resolution modes which the Cirrus Logic BIOS does not support (i.e. >=
2208 1280x1024x16), then you should use the VESA VBE virtual graphic card
2209 (option @option{-std-vga}).
2211 @subsubsection CPU usage reduction
2213 Windows 9x does not correctly use the CPU HLT
2214 instruction. The result is that it takes host CPU cycles even when
2215 idle. You can install the utility from
2216 @url{http://www.user.cityline.ru/~maxamn/amnhltm.zip} to solve this
2217 problem. Note that no such tool is needed for NT, 2000 or XP.
2219 @subsubsection Windows 2000 disk full problem
2221 Windows 2000 has a bug which gives a disk full problem during its
2222 installation. When installing it, use the @option{-win2k-hack} QEMU
2223 option to enable a specific workaround. After Windows 2000 is
2224 installed, you no longer need this option (this option slows down the
2227 @subsubsection Windows 2000 shutdown
2229 Windows 2000 cannot automatically shutdown in QEMU although Windows 98
2230 can. It comes from the fact that Windows 2000 does not automatically
2231 use the APM driver provided by the BIOS.
2233 In order to correct that, do the following (thanks to Struan
2234 Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
2235 Add/Troubleshoot a device => Add a new device & Next => No, select the
2236 hardware from a list & Next => NT Apm/Legacy Support & Next => Next
2237 (again) a few times. Now the driver is installed and Windows 2000 now
2238 correctly instructs QEMU to shutdown at the appropriate moment.
2240 @subsubsection Share a directory between Unix and Windows
2242 See @ref{sec_invocation} about the help of the option @option{-smb}.
2244 @subsubsection Windows XP security problem
2246 Some releases of Windows XP install correctly but give a security
2249 A problem is preventing Windows from accurately checking the
2250 license for this computer. Error code: 0x800703e6.
2253 The workaround is to install a service pack for XP after a boot in safe
2254 mode. Then reboot, and the problem should go away. Since there is no
2255 network while in safe mode, its recommended to download the full
2256 installation of SP1 or SP2 and transfer that via an ISO or using the
2257 vvfat block device ("-hdb fat:directory_which_holds_the_SP").
2259 @subsection MS-DOS and FreeDOS
2261 @subsubsection CPU usage reduction
2263 DOS does not correctly use the CPU HLT instruction. The result is that
2264 it takes host CPU cycles even when idle. You can install the utility
2265 from @url{http://www.vmware.com/software/dosidle210.zip} to solve this
2268 @node QEMU System emulator for non PC targets
2269 @chapter QEMU System emulator for non PC targets
2271 QEMU is a generic emulator and it emulates many non PC
2272 machines. Most of the options are similar to the PC emulator. The
2273 differences are mentioned in the following sections.
2276 * QEMU PowerPC System emulator::
2277 * Sparc32 System emulator::
2278 * Sparc64 System emulator::
2279 * MIPS System emulator::
2280 * ARM System emulator::
2281 * ColdFire System emulator::
2284 @node QEMU PowerPC System emulator
2285 @section QEMU PowerPC System emulator
2287 Use the executable @file{qemu-system-ppc} to simulate a complete PREP
2288 or PowerMac PowerPC system.
2290 QEMU emulates the following PowerMac peripherals:
2296 PCI VGA compatible card with VESA Bochs Extensions
2298 2 PMAC IDE interfaces with hard disk and CD-ROM support
2304 VIA-CUDA with ADB keyboard and mouse.
2307 QEMU emulates the following PREP peripherals:
2313 PCI VGA compatible card with VESA Bochs Extensions
2315 2 IDE interfaces with hard disk and CD-ROM support
2319 NE2000 network adapters
2323 PREP Non Volatile RAM
2325 PC compatible keyboard and mouse.
2328 QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS available at
2329 @url{http://perso.magic.fr/l_indien/OpenHackWare/index.htm}.
2331 @c man begin OPTIONS
2333 The following options are specific to the PowerPC emulation:
2337 @item -g WxH[xDEPTH]
2339 Set the initial VGA graphic mode. The default is 800x600x15.
2346 More information is available at
2347 @url{http://perso.magic.fr/l_indien/qemu-ppc/}.
2349 @node Sparc32 System emulator
2350 @section Sparc32 System emulator
2352 Use the executable @file{qemu-system-sparc} to simulate the following
2353 Sun4m architecture machines:
2368 SPARCstation Voyager
2375 The emulation is somewhat complete. SMP up to 16 CPUs is supported,
2376 but Linux limits the number of usable CPUs to 4.
2378 It's also possible to simulate a SPARCstation 2 (sun4c architecture),
2379 SPARCserver 1000, or SPARCcenter 2000 (sun4d architecture), but these
2380 emulators are not usable yet.
2382 QEMU emulates the following sun4m/sun4c/sun4d peripherals:
2390 Lance (Am7990) Ethernet
2392 Non Volatile RAM M48T02/M48T08
2394 Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
2395 and power/reset logic
2397 ESP SCSI controller with hard disk and CD-ROM support
2399 Floppy drive (not on SS-600MP)
2401 CS4231 sound device (only on SS-5, not working yet)
2404 The number of peripherals is fixed in the architecture. Maximum
2405 memory size depends on the machine type, for SS-5 it is 256MB and for
2408 Since version 0.8.2, QEMU uses OpenBIOS
2409 @url{http://www.openbios.org/}. OpenBIOS is a free (GPL v2) portable
2410 firmware implementation. The goal is to implement a 100% IEEE
2411 1275-1994 (referred to as Open Firmware) compliant firmware.
2413 A sample Linux 2.6 series kernel and ram disk image are available on
2414 the QEMU web site. There are still issues with NetBSD and OpenBSD, but
2415 some kernel versions work. Please note that currently Solaris kernels
2416 don't work probably due to interface issues between OpenBIOS and
2419 @c man begin OPTIONS
2421 The following options are specific to the Sparc32 emulation:
2425 @item -g WxHx[xDEPTH]
2427 Set the initial TCX graphic mode. The default is 1024x768x8, currently
2428 the only other possible mode is 1024x768x24.
2430 @item -prom-env string
2432 Set OpenBIOS variables in NVRAM, for example:
2435 qemu-system-sparc -prom-env 'auto-boot?=false' \
2436 -prom-env 'boot-device=sd(0,2,0):d' -prom-env 'boot-args=linux single'
2439 @item -M [SS-4|SS-5|SS-10|SS-20|SS-600MP|LX|Voyager|SPARCClassic|SPARCbook|SS-2|SS-1000|SS-2000]
2441 Set the emulated machine type. Default is SS-5.
2447 @node Sparc64 System emulator
2448 @section Sparc64 System emulator
2450 Use the executable @file{qemu-system-sparc64} to simulate a Sun4u
2451 (UltraSPARC PC-like machine), Sun4v (T1 PC-like machine), or generic
2452 Niagara (T1) machine. The emulator is not usable for anything yet, but
2453 it can launch some kernels.
2455 QEMU emulates the following peripherals:
2459 UltraSparc IIi APB PCI Bridge
2461 PCI VGA compatible card with VESA Bochs Extensions
2463 PS/2 mouse and keyboard
2465 Non Volatile RAM M48T59
2467 PC-compatible serial ports
2469 2 PCI IDE interfaces with hard disk and CD-ROM support
2474 @c man begin OPTIONS
2476 The following options are specific to the Sparc64 emulation:
2480 @item -prom-env string
2482 Set OpenBIOS variables in NVRAM, for example:
2485 qemu-system-sparc64 -prom-env 'auto-boot?=false'
2488 @item -M [sun4u|sun4v|Niagara]
2490 Set the emulated machine type. The default is sun4u.
2496 @node MIPS System emulator
2497 @section MIPS System emulator
2499 Four executables cover simulation of 32 and 64-bit MIPS systems in
2500 both endian options, @file{qemu-system-mips}, @file{qemu-system-mipsel}
2501 @file{qemu-system-mips64} and @file{qemu-system-mips64el}.
2502 Five different machine types are emulated:
2506 A generic ISA PC-like machine "mips"
2508 The MIPS Malta prototype board "malta"
2510 An ACER Pica "pica61". This machine needs the 64-bit emulator.
2512 MIPS emulator pseudo board "mipssim"
2514 A MIPS Magnum R4000 machine "magnum". This machine needs the 64-bit emulator.
2517 The generic emulation is supported by Debian 'Etch' and is able to
2518 install Debian into a virtual disk image. The following devices are
2523 A range of MIPS CPUs, default is the 24Kf
2525 PC style serial port
2532 The Malta emulation supports the following devices:
2536 Core board with MIPS 24Kf CPU and Galileo system controller
2538 PIIX4 PCI/USB/SMbus controller
2540 The Multi-I/O chip's serial device
2542 PCnet32 PCI network card
2544 Malta FPGA serial device
2546 Cirrus VGA graphics card
2549 The ACER Pica emulation supports:
2555 PC-style IRQ and DMA controllers
2562 The mipssim pseudo board emulation provides an environment similiar
2563 to what the proprietary MIPS emulator uses for running Linux.
2568 A range of MIPS CPUs, default is the 24Kf
2570 PC style serial port
2572 MIPSnet network emulation
2575 The MIPS Magnum R4000 emulation supports:
2581 PC-style IRQ controller
2591 @node ARM System emulator
2592 @section ARM System emulator
2594 Use the executable @file{qemu-system-arm} to simulate a ARM
2595 machine. The ARM Integrator/CP board is emulated with the following
2600 ARM926E, ARM1026E, ARM946E, ARM1136 or Cortex-A8 CPU
2604 SMC 91c111 Ethernet adapter
2606 PL110 LCD controller
2608 PL050 KMI with PS/2 keyboard and mouse.
2610 PL181 MultiMedia Card Interface with SD card.
2613 The ARM Versatile baseboard is emulated with the following devices:
2617 ARM926E, ARM1136 or Cortex-A8 CPU
2619 PL190 Vectored Interrupt Controller
2623 SMC 91c111 Ethernet adapter
2625 PL110 LCD controller
2627 PL050 KMI with PS/2 keyboard and mouse.
2629 PCI host bridge. Note the emulated PCI bridge only provides access to
2630 PCI memory space. It does not provide access to PCI IO space.
2631 This means some devices (eg. ne2k_pci NIC) are not usable, and others
2632 (eg. rtl8139 NIC) are only usable when the guest drivers use the memory
2633 mapped control registers.
2635 PCI OHCI USB controller.
2637 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices.
2639 PL181 MultiMedia Card Interface with SD card.
2642 The ARM RealView Emulation baseboard is emulated with the following devices:
2646 ARM926E, ARM1136, ARM11MPCORE(x4) or Cortex-A8 CPU
2648 ARM AMBA Generic/Distributed Interrupt Controller
2652 SMC 91c111 Ethernet adapter
2654 PL110 LCD controller
2656 PL050 KMI with PS/2 keyboard and mouse
2660 PCI OHCI USB controller
2662 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices
2664 PL181 MultiMedia Card Interface with SD card.
2667 The XScale-based clamshell PDA models ("Spitz", "Akita", "Borzoi"
2668 and "Terrier") emulation includes the following peripherals:
2672 Intel PXA270 System-on-chip (ARM V5TE core)
2676 IBM/Hitachi DSCM microdrive in a PXA PCMCIA slot - not in "Akita"
2678 On-chip OHCI USB controller
2680 On-chip LCD controller
2682 On-chip Real Time Clock
2684 TI ADS7846 touchscreen controller on SSP bus
2686 Maxim MAX1111 analog-digital converter on I@math{^2}C bus
2688 GPIO-connected keyboard controller and LEDs
2690 Secure Digital card connected to PXA MMC/SD host
2694 WM8750 audio CODEC on I@math{^2}C and I@math{^2}S busses
2697 The Palm Tungsten|E PDA (codename "Cheetah") emulation includes the
2702 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
2704 ROM and RAM memories (ROM firmware image can be loaded with -option-rom)
2706 On-chip LCD controller
2708 On-chip Real Time Clock
2710 TI TSC2102i touchscreen controller / analog-digital converter / Audio
2711 CODEC, connected through MicroWire and I@math{^2}S busses
2713 GPIO-connected matrix keypad
2715 Secure Digital card connected to OMAP MMC/SD host
2720 Nokia N800 and N810 internet tablets (known also as RX-34 and RX-44 / 48)
2721 emulation supports the following elements:
2725 Texas Instruments OMAP2420 System-on-chip (ARM 1136 core)
2727 RAM and non-volatile OneNAND Flash memories
2729 Display connected to EPSON remote framebuffer chip and OMAP on-chip
2730 display controller and a LS041y3 MIPI DBI-C controller
2732 TI TSC2301 (in N800) and TI TSC2005 (in N810) touchscreen controllers
2733 driven through SPI bus
2735 National Semiconductor LM8323-controlled qwerty keyboard driven
2736 through I@math{^2}C bus
2738 Secure Digital card connected to OMAP MMC/SD host
2740 Three OMAP on-chip UARTs and on-chip STI debugging console
2742 A Bluetooth(R) transciever and HCI connected to an UART
2744 Mentor Graphics "Inventra" dual-role USB controller embedded in a TI
2745 TUSB6010 chip - only USB host mode is supported
2747 TI TMP105 temperature sensor driven through I@math{^2}C bus
2749 TI TWL92230C power management companion with an RTC on I@math{^2}C bus
2751 Nokia RETU and TAHVO multi-purpose chips with an RTC, connected
2755 The Luminary Micro Stellaris LM3S811EVB emulation includes the following
2762 64k Flash and 8k SRAM.
2764 Timers, UARTs, ADC and I@math{^2}C interface.
2766 OSRAM Pictiva 96x16 OLED with SSD0303 controller on I@math{^2}C bus.
2769 The Luminary Micro Stellaris LM3S6965EVB emulation includes the following
2776 256k Flash and 64k SRAM.
2778 Timers, UARTs, ADC, I@math{^2}C and SSI interfaces.
2780 OSRAM Pictiva 128x64 OLED with SSD0323 controller connected via SSI.
2783 The Freecom MusicPal internet radio emulation includes the following
2788 Marvell MV88W8618 ARM core.
2790 32 MB RAM, 256 KB SRAM, 8 MB flash.
2794 MV88W8xx8 Ethernet controller
2796 MV88W8618 audio controller, WM8750 CODEC and mixer
2798 128×64 display with brightness control
2800 2 buttons, 2 navigation wheels with button function
2803 A Linux 2.6 test image is available on the QEMU web site. More
2804 information is available in the QEMU mailing-list archive.
2806 @node ColdFire System emulator
2807 @section ColdFire System emulator
2809 Use the executable @file{qemu-system-m68k} to simulate a ColdFire machine.
2810 The emulator is able to boot a uClinux kernel.
2812 The M5208EVB emulation includes the following devices:
2816 MCF5208 ColdFire V2 Microprocessor (ISA A+ with EMAC).
2818 Three Two on-chip UARTs.
2820 Fast Ethernet Controller (FEC)
2823 The AN5206 emulation includes the following devices:
2827 MCF5206 ColdFire V2 Microprocessor.
2832 @node QEMU User space emulator
2833 @chapter QEMU User space emulator
2836 * Supported Operating Systems ::
2837 * Linux User space emulator::
2838 * Mac OS X/Darwin User space emulator ::
2839 * BSD User space emulator ::
2842 @node Supported Operating Systems
2843 @section Supported Operating Systems
2845 The following OS are supported in user space emulation:
2849 Linux (referred as qemu-linux-user)
2851 Mac OS X/Darwin (referred as qemu-darwin-user)
2853 BSD (referred as qemu-bsd-user)
2856 @node Linux User space emulator
2857 @section Linux User space emulator
2862 * Command line options::
2867 @subsection Quick Start
2869 In order to launch a Linux process, QEMU needs the process executable
2870 itself and all the target (x86) dynamic libraries used by it.
2874 @item On x86, you can just try to launch any process by using the native
2878 qemu-i386 -L / /bin/ls
2881 @code{-L /} tells that the x86 dynamic linker must be searched with a
2884 @item Since QEMU is also a linux process, you can launch qemu with
2885 qemu (NOTE: you can only do that if you compiled QEMU from the sources):
2888 qemu-i386 -L / qemu-i386 -L / /bin/ls
2891 @item On non x86 CPUs, you need first to download at least an x86 glibc
2892 (@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
2893 @code{LD_LIBRARY_PATH} is not set:
2896 unset LD_LIBRARY_PATH
2899 Then you can launch the precompiled @file{ls} x86 executable:
2902 qemu-i386 tests/i386/ls
2904 You can look at @file{qemu-binfmt-conf.sh} so that
2905 QEMU is automatically launched by the Linux kernel when you try to
2906 launch x86 executables. It requires the @code{binfmt_misc} module in the
2909 @item The x86 version of QEMU is also included. You can try weird things such as:
2911 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 \
2912 /usr/local/qemu-i386/bin/ls-i386
2918 @subsection Wine launch
2922 @item Ensure that you have a working QEMU with the x86 glibc
2923 distribution (see previous section). In order to verify it, you must be
2927 qemu-i386 /usr/local/qemu-i386/bin/ls-i386
2930 @item Download the binary x86 Wine install
2931 (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
2933 @item Configure Wine on your account. Look at the provided script
2934 @file{/usr/local/qemu-i386/@/bin/wine-conf.sh}. Your previous
2935 @code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
2937 @item Then you can try the example @file{putty.exe}:
2940 qemu-i386 /usr/local/qemu-i386/wine/bin/wine \
2941 /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
2946 @node Command line options
2947 @subsection Command line options
2950 usage: qemu-i386 [-h] [-d] [-L path] [-s size] [-cpu model] [-g port] program [arguments...]
2957 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
2959 Set the x86 stack size in bytes (default=524288)
2961 Select CPU model (-cpu ? for list and additional feature selection)
2968 Activate log (logfile=/tmp/qemu.log)
2970 Act as if the host page size was 'pagesize' bytes
2972 Wait gdb connection to port
2975 Environment variables:
2979 Print system calls and arguments similar to the 'strace' program
2980 (NOTE: the actual 'strace' program will not work because the user
2981 space emulator hasn't implemented ptrace). At the moment this is
2982 incomplete. All system calls that don't have a specific argument
2983 format are printed with information for six arguments. Many
2984 flag-style arguments don't have decoders and will show up as numbers.
2987 @node Other binaries
2988 @subsection Other binaries
2990 @command{qemu-arm} is also capable of running ARM "Angel" semihosted ELF
2991 binaries (as implemented by the arm-elf and arm-eabi Newlib/GDB
2992 configurations), and arm-uclinux bFLT format binaries.
2994 @command{qemu-m68k} is capable of running semihosted binaries using the BDM
2995 (m5xxx-ram-hosted.ld) or m68k-sim (sim.ld) syscall interfaces, and
2996 coldfire uClinux bFLT format binaries.
2998 The binary format is detected automatically.
3000 @command{qemu-sparc} can execute Sparc32 binaries (Sparc32 CPU, 32 bit ABI).
3002 @command{qemu-sparc32plus} can execute Sparc32 and SPARC32PLUS binaries
3003 (Sparc64 CPU, 32 bit ABI).
3005 @command{qemu-sparc64} can execute some Sparc64 (Sparc64 CPU, 64 bit ABI) and
3006 SPARC32PLUS binaries (Sparc64 CPU, 32 bit ABI).
3008 @node Mac OS X/Darwin User space emulator
3009 @section Mac OS X/Darwin User space emulator
3012 * Mac OS X/Darwin Status::
3013 * Mac OS X/Darwin Quick Start::
3014 * Mac OS X/Darwin Command line options::
3017 @node Mac OS X/Darwin Status
3018 @subsection Mac OS X/Darwin Status
3022 target x86 on x86: Most apps (Cocoa and Carbon too) works. [1]
3024 target PowerPC on x86: Not working as the ppc commpage can't be mapped (yet!)
3026 target PowerPC on PowerPC: Most apps (Cocoa and Carbon too) works. [1]
3028 target x86 on PowerPC: most utilities work. Cocoa and Carbon apps are not yet supported.
3031 [1] If you're host commpage can be executed by qemu.
3033 @node Mac OS X/Darwin Quick Start
3034 @subsection Quick Start
3036 In order to launch a Mac OS X/Darwin process, QEMU needs the process executable
3037 itself and all the target dynamic libraries used by it. If you don't have the FAT
3038 libraries (you're running Mac OS X/ppc) you'll need to obtain it from a Mac OS X
3039 CD or compile them by hand.
3043 @item On x86, you can just try to launch any process by using the native
3050 or to run the ppc version of the executable:
3056 @item On ppc, you'll have to tell qemu where your x86 libraries (and dynamic linker)
3060 qemu-i386 -L /opt/x86_root/ /bin/ls
3063 @code{-L /opt/x86_root/} tells that the dynamic linker (dyld) path is in
3064 @file{/opt/x86_root/usr/bin/dyld}.
3068 @node Mac OS X/Darwin Command line options
3069 @subsection Command line options
3072 usage: qemu-i386 [-h] [-d] [-L path] [-s size] program [arguments...]
3079 Set the library root path (default=/)
3081 Set the stack size in bytes (default=524288)
3088 Activate log (logfile=/tmp/qemu.log)
3090 Act as if the host page size was 'pagesize' bytes
3093 @node BSD User space emulator
3094 @section BSD User space emulator
3099 * BSD Command line options::
3103 @subsection BSD Status
3107 target Sparc64 on Sparc64: Some trivial programs work.
3110 @node BSD Quick Start
3111 @subsection Quick Start
3113 In order to launch a BSD process, QEMU needs the process executable
3114 itself and all the target dynamic libraries used by it.
3118 @item On Sparc64, you can just try to launch any process by using the native
3122 qemu-sparc64 /bin/ls
3127 @node BSD Command line options
3128 @subsection Command line options
3131 usage: qemu-sparc64 [-h] [-d] [-L path] [-s size] [-bsd type] program [arguments...]
3138 Set the library root path (default=/)
3140 Set the stack size in bytes (default=524288)
3142 Set the type of the emulated BSD Operating system. Valid values are
3143 FreeBSD, NetBSD and OpenBSD (default).
3150 Activate log (logfile=/tmp/qemu.log)
3152 Act as if the host page size was 'pagesize' bytes
3156 @chapter Compilation from the sources
3161 * Cross compilation for Windows with Linux::
3168 @subsection Compilation
3170 First you must decompress the sources:
3173 tar zxvf qemu-x.y.z.tar.gz
3177 Then you configure QEMU and build it (usually no options are needed):
3183 Then type as root user:
3187 to install QEMU in @file{/usr/local}.
3189 @subsection GCC version
3191 In order to compile QEMU successfully, it is very important that you
3192 have the right tools. The most important one is gcc. On most hosts and
3193 in particular on x86 ones, @emph{gcc 4.x is not supported}. If your
3194 Linux distribution includes a gcc 4.x compiler, you can usually
3195 install an older version (it is invoked by @code{gcc32} or
3196 @code{gcc34}). The QEMU configure script automatically probes for
3197 these older versions so that usually you don't have to do anything.
3203 @item Install the current versions of MSYS and MinGW from
3204 @url{http://www.mingw.org/}. You can find detailed installation
3205 instructions in the download section and the FAQ.
3208 the MinGW development library of SDL 1.2.x
3209 (@file{SDL-devel-1.2.x-@/mingw32.tar.gz}) from
3210 @url{http://www.libsdl.org}. Unpack it in a temporary place, and
3211 unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
3212 directory. Edit the @file{sdl-config} script so that it gives the
3213 correct SDL directory when invoked.
3215 @item Extract the current version of QEMU.
3217 @item Start the MSYS shell (file @file{msys.bat}).
3219 @item Change to the QEMU directory. Launch @file{./configure} and
3220 @file{make}. If you have problems using SDL, verify that
3221 @file{sdl-config} can be launched from the MSYS command line.
3223 @item You can install QEMU in @file{Program Files/Qemu} by typing
3224 @file{make install}. Don't forget to copy @file{SDL.dll} in
3225 @file{Program Files/Qemu}.
3229 @node Cross compilation for Windows with Linux
3230 @section Cross compilation for Windows with Linux
3234 Install the MinGW cross compilation tools available at
3235 @url{http://www.mingw.org/}.
3238 Install the Win32 version of SDL (@url{http://www.libsdl.org}) by
3239 unpacking @file{i386-mingw32msvc.tar.gz}. Set up the PATH environment
3240 variable so that @file{i386-mingw32msvc-sdl-config} can be launched by
3241 the QEMU configuration script.
3244 Configure QEMU for Windows cross compilation:
3246 ./configure --enable-mingw32
3248 If necessary, you can change the cross-prefix according to the prefix
3249 chosen for the MinGW tools with --cross-prefix. You can also use
3250 --prefix to set the Win32 install path.
3252 @item You can install QEMU in the installation directory by typing
3253 @file{make install}. Don't forget to copy @file{SDL.dll} in the
3254 installation directory.
3258 Note: Currently, Wine does not seem able to launch
3264 The Mac OS X patches are not fully merged in QEMU, so you should look
3265 at the QEMU mailing list archive to have all the necessary