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 Beige 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, Terrier and Tosa 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)
92 @item Gumstix "Connex" and "Verdex" motherboards (PXA255/270).
93 @item Siemens SX1 smartphone (OMAP310 processor)
96 For user emulation, x86, PowerPC, ARM, 32-bit MIPS, Sparc32/64 and ColdFire(m68k) CPUs are supported.
101 If you want to compile QEMU yourself, see @ref{compilation}.
104 * install_linux:: Linux
105 * install_windows:: Windows
106 * install_mac:: Macintosh
112 If a precompiled package is available for your distribution - you just
113 have to install it. Otherwise, see @ref{compilation}.
115 @node install_windows
118 Download the experimental binary installer at
119 @url{http://www.free.oszoo.org/@/download.html}.
124 Download the experimental binary installer at
125 @url{http://www.free.oszoo.org/@/download.html}.
127 @node QEMU PC System emulator
128 @chapter QEMU PC System emulator
131 * pcsys_introduction:: Introduction
132 * pcsys_quickstart:: Quick Start
133 * sec_invocation:: Invocation
135 * pcsys_monitor:: QEMU Monitor
136 * disk_images:: Disk Images
137 * pcsys_network:: Network emulation
138 * direct_linux_boot:: Direct Linux Boot
139 * pcsys_usb:: USB emulation
140 * vnc_security:: VNC security
141 * gdb_usage:: GDB usage
142 * pcsys_os_specific:: Target OS specific information
145 @node pcsys_introduction
146 @section Introduction
148 @c man begin DESCRIPTION
150 The QEMU PC System emulator simulates the
151 following peripherals:
155 i440FX host PCI bridge and PIIX3 PCI to ISA bridge
157 Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
158 extensions (hardware level, including all non standard modes).
160 PS/2 mouse and keyboard
162 2 PCI IDE interfaces with hard disk and CD-ROM support
166 PCI/ISA PCI network adapters
170 Creative SoundBlaster 16 sound card
172 ENSONIQ AudioPCI ES1370 sound card
174 Intel 82801AA AC97 Audio compatible sound card
176 Adlib(OPL2) - Yamaha YM3812 compatible chip
178 Gravis Ultrasound GF1 sound card
180 CS4231A compatible sound card
182 PCI UHCI USB controller and a virtual USB hub.
185 SMP is supported with up to 255 CPUs.
187 Note that adlib, gus and cs4231a are only available when QEMU was
188 configured with --audio-card-list option containing the name(s) of
191 QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
194 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
196 QEMU uses GUS emulation(GUSEMU32 @url{http://www.deinmeister.de/gusemu/})
197 by Tibor "TS" Schütz.
199 CS4231A is the chip used in Windows Sound System and GUSMAX products
203 @node pcsys_quickstart
206 Download and uncompress the linux image (@file{linux.img}) and type:
212 Linux should boot and give you a prompt.
218 @c man begin SYNOPSIS
219 usage: qemu [options] [@var{disk_image}]
224 @var{disk_image} is a raw hard disk image for IDE hard disk 0.
228 @item -M @var{machine}
229 Select the emulated @var{machine} (@code{-M ?} for list)
231 @item -fda @var{file}
232 @item -fdb @var{file}
233 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
234 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
236 @item -hda @var{file}
237 @item -hdb @var{file}
238 @item -hdc @var{file}
239 @item -hdd @var{file}
240 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
242 @item -cdrom @var{file}
243 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
244 @option{-cdrom} at the same time). You can use the host CD-ROM by
245 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
247 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
249 Define a new drive. Valid options are:
252 @item file=@var{file}
253 This option defines which disk image (@pxref{disk_images}) to use with
254 this drive. If the filename contains comma, you must double it
255 (for instance, "file=my,,file" to use file "my,file").
256 @item if=@var{interface}
257 This option defines on which type on interface the drive is connected.
258 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
259 @item bus=@var{bus},unit=@var{unit}
260 These options define where is connected the drive by defining the bus number and
262 @item index=@var{index}
263 This option defines where is connected the drive by using an index in the list
264 of available connectors of a given interface type.
265 @item media=@var{media}
266 This option defines the type of the media: disk or cdrom.
267 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
268 These options have the same definition as they have in @option{-hdachs}.
269 @item snapshot=@var{snapshot}
270 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
271 @item cache=@var{cache}
272 @var{cache} is "none", "writeback", or "writethrough" and controls how the host cache is used to access block data.
273 @item format=@var{format}
274 Specify which disk @var{format} will be used rather than detecting
275 the format. Can be used to specifiy format=raw to avoid interpreting
276 an untrusted format header.
277 @item serial=@var{serial}
278 This option specifies the serial number to assign to the device.
279 @item boot=@var{boot}
280 @var{boot} if "on" enables extboot for a given drive so it can be used as a boot drive.
283 By default, writethrough caching is used for all block device. This means that
284 the host page cache will be used to read and write data but write notification
285 will be sent to the guest only when the data has been reported as written by
286 the storage subsystem.
288 Writeback caching will report data writes as completed as soon as the data is
289 present in the host page cache. This is safe as long as you trust your host.
290 If your host crashes or loses power, then the guest may experience data
291 corruption. When using the @option{-snapshot} option, writeback caching is
294 The host page can be avoided entirely with @option{cache=none}. This will
295 attempt to do disk IO directly to the guests memory. QEMU may still perform
296 an internal copy of the data.
298 Some block drivers perform badly with @option{cache=writethrough}, most notably,
299 qcow2. If performance is more important than correctness,
300 @option{cache=writeback} should be used with qcow2. By default, if no explicit
301 caching is specified for a qcow2 disk image, @option{cache=writeback} will be
302 used. For all other disk types, @option{cache=writethrough} is the default.
304 Instead of @option{-cdrom} you can use:
306 qemu -drive file=file,index=2,media=cdrom
309 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
312 qemu -drive file=file,index=0,media=disk
313 qemu -drive file=file,index=1,media=disk
314 qemu -drive file=file,index=2,media=disk
315 qemu -drive file=file,index=3,media=disk
318 You can connect a CDROM to the slave of ide0:
320 qemu -drive file=file,if=ide,index=1,media=cdrom
323 If you don't specify the "file=" argument, you define an empty drive:
325 qemu -drive if=ide,index=1,media=cdrom
328 You can connect a SCSI disk with unit ID 6 on the bus #0:
330 qemu -drive file=file,if=scsi,bus=0,unit=6
333 To boot from a SCSI disk, one would use:
336 qemu -drive file=file,if=scsi,boot=on
339 Instead of @option{-fda}, @option{-fdb}, you can use:
341 qemu -drive file=file,index=0,if=floppy
342 qemu -drive file=file,index=1,if=floppy
345 By default, @var{interface} is "ide" and @var{index} is automatically
348 qemu -drive file=a -drive file=b"
355 @item -boot [a|c|d|n]
356 Boot on floppy (a), hard disk (c), CD-ROM (d), or Etherboot (n). Hard disk boot
360 Write to temporary files instead of disk image files. In this case,
361 the raw disk image you use is not written back. You can however force
362 the write back by pressing @key{C-a s} (@pxref{disk_images}).
365 Disable boot signature checking for floppy disks in Bochs BIOS. It may
366 be needed to boot from old floppy disks.
369 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
370 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
371 gigabytes respectively.
373 @item -cpu @var{model}
374 Select CPU model (-cpu ? for list and additional feature selection)
377 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
378 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
383 Will show the audio subsystem help: list of drivers, tunable
386 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
388 Enable audio and selected sound hardware. Use ? to print all
389 available sound hardware.
392 qemu -soundhw sb16,adlib disk.img
393 qemu -soundhw es1370 disk.img
394 qemu -soundhw ac97 disk.img
395 qemu -soundhw all disk.img
399 Note that Linux's i810_audio OSS kernel (for AC97) module might
400 require manually specifying clocking.
403 modprobe i810_audio clocking=48000
407 Set the real time clock to local time (the default is to UTC
408 time). This option is needed to have correct date in MS-DOS or
411 @item -startdate @var{date}
412 Set the initial date of the real time clock. Valid formats for
413 @var{date} are: @code{now} or @code{2006-06-17T16:01:21} or
414 @code{2006-06-17}. The default value is @code{now}.
416 @item -pidfile @var{file}
417 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
421 Daemonize the QEMU process after initialization. QEMU will not detach from
422 standard IO until it is ready to receive connections on any of its devices.
423 This option is a useful way for external programs to launch QEMU without having
424 to cope with initialization race conditions.
427 Use it when installing Windows 2000 to avoid a disk full bug. After
428 Windows 2000 is installed, you no longer need this option (this option
429 slows down the IDE transfers).
431 @item -option-rom @var{file}
432 Load the contents of @var{file} as an option ROM.
433 This option is useful to load things like EtherBoot.
435 @item -name @var{name}
436 Sets the @var{name} of the guest.
437 This name will be displayed in the SDL window caption.
438 The @var{name} will also be used for the VNC server.
447 Normally, QEMU uses SDL to display the VGA output. With this option,
448 you can totally disable graphical output so that QEMU is a simple
449 command line application. The emulated serial port is redirected on
450 the console. Therefore, you can still use QEMU to debug a Linux kernel
451 with a serial console.
455 Normally, QEMU uses SDL to display the VGA output. With this option,
456 QEMU can display the VGA output when in text mode using a
457 curses/ncurses interface. Nothing is displayed in graphical mode.
461 Do not use decorations for SDL windows and start them using the whole
462 available screen space. This makes the using QEMU in a dedicated desktop
463 workspace more convenient.
467 Disable SDL window close capability.
470 Start in full screen.
472 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
474 Normally, QEMU uses SDL to display the VGA output. With this option,
475 you can have QEMU listen on VNC display @var{display} and redirect the VGA
476 display over the VNC session. It is very useful to enable the usb
477 tablet device when using this option (option @option{-usbdevice
478 tablet}). When using the VNC display, you must use the @option{-k}
479 parameter to set the keyboard layout if you are not using en-us. Valid
480 syntax for the @var{display} is
484 @item @var{host}:@var{d}
486 TCP connections will only be allowed from @var{host} on display @var{d}.
487 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
488 be omitted in which case the server will accept connections from any host.
490 @item @code{unix}:@var{path}
492 Connections will be allowed over UNIX domain sockets where @var{path} is the
493 location of a unix socket to listen for connections on.
497 VNC is initialized but not started. The monitor @code{change} command
498 can be used to later start the VNC server.
502 Following the @var{display} value there may be one or more @var{option} flags
503 separated by commas. Valid options are
509 Connect to a listening VNC client via a ``reverse'' connection. The
510 client is specified by the @var{display}. For reverse network
511 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
512 is a TCP port number, not a display number.
516 Require that password based authentication is used for client connections.
517 The password must be set separately using the @code{change} command in the
522 Require that client use TLS when communicating with the VNC server. This
523 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
524 attack. It is recommended that this option be combined with either the
525 @var{x509} or @var{x509verify} options.
527 @item x509=@var{/path/to/certificate/dir}
529 Valid if @option{tls} is specified. Require that x509 credentials are used
530 for negotiating the TLS session. The server will send its x509 certificate
531 to the client. It is recommended that a password be set on the VNC server
532 to provide authentication of the client when this is used. The path following
533 this option specifies where the x509 certificates are to be loaded from.
534 See the @ref{vnc_security} section for details on generating certificates.
536 @item x509verify=@var{/path/to/certificate/dir}
538 Valid if @option{tls} is specified. Require that x509 credentials are used
539 for negotiating the TLS session. The server will send its x509 certificate
540 to the client, and request that the client send its own x509 certificate.
541 The server will validate the client's certificate against the CA certificate,
542 and reject clients when validation fails. If the certificate authority is
543 trusted, this is a sufficient authentication mechanism. You may still wish
544 to set a password on the VNC server as a second authentication layer. The
545 path following this option specifies where the x509 certificates are to
546 be loaded from. See the @ref{vnc_security} section for details on generating
551 @item -k @var{language}
553 Use keyboard layout @var{language} (for example @code{fr} for
554 French). This option is only needed where it is not easy to get raw PC
555 keycodes (e.g. on Macs, with some X11 servers or with a VNC
556 display). You don't normally need to use it on PC/Linux or PC/Windows
559 The available layouts are:
561 ar de-ch es fo fr-ca hu ja mk no pt-br sv
562 da en-gb et fr fr-ch is lt nl pl ru th
563 de en-us fi fr-be hr it lv nl-be pt sl tr
566 The default is @code{en-us}.
574 Enable the USB driver (will be the default soon)
576 @item -usbdevice @var{devname}
577 Add the USB device @var{devname}. @xref{usb_devices}.
582 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
585 Pointer device that uses absolute coordinates (like a touchscreen). This
586 means qemu is able to report the mouse position without having to grab the
587 mouse. Also overrides the PS/2 mouse emulation when activated.
589 @item disk:[format=@var{format}]:file
590 Mass storage device based on file. The optional @var{format} argument
591 will be used rather than detecting the format. Can be used to specifiy
592 format=raw to avoid interpreting an untrusted format header.
595 Pass through the host device identified by bus.addr (Linux only).
597 @item host:vendor_id:product_id
598 Pass through the host device identified by vendor_id:product_id (Linux only).
600 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
601 Serial converter to host character device @var{dev}, see @code{-serial} for the
605 Braille device. This will use BrlAPI to display the braille output on a real
609 Network adapter that supports CDC ethernet and RNDIS protocols.
619 @item -net nic[,vlan=@var{n}][,macaddr=@var{addr}][,model=@var{type}][,name=@var{name}]
620 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
621 = 0 is the default). The NIC is an rtl8139 by default on the PC
622 target. Optionally, the MAC address can be changed to @var{addr}
623 and a @var{name} can be assigned for use in monitor commands. If no
624 @option{-net} option is specified, a single NIC is created.
625 Qemu can emulate several different models of network card.
626 Valid values for @var{type} are
627 @code{i82551}, @code{i82557b}, @code{i82559er},
628 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
629 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
630 Not all devices are supported on all targets. Use -net nic,model=?
631 for a list of available devices for your target.
633 @item -net user[,vlan=@var{n}][,hostname=@var{name}][,name=@var{name}]
634 Use the user mode network stack which requires no administrator
635 privilege to run. @option{hostname=name} can be used to specify the client
636 hostname reported by the builtin DHCP server.
638 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}]
639 Connect the host TAP network interface @var{name} to VLAN @var{n}, use
640 the network script @var{file} to configure it and the network script
641 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
642 automatically provides one. @option{fd}=@var{h} can be used to specify
643 the handle of an already opened host TAP interface. The default network
644 configure script is @file{/etc/qemu-ifup} and the default network
645 deconfigure script is @file{/etc/qemu-ifdown}. Use @option{script=no}
646 or @option{downscript=no} to disable script execution. Example:
649 qemu linux.img -net nic -net tap
652 More complicated example (two NICs, each one connected to a TAP device)
654 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
655 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
659 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
661 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
662 machine using a TCP socket connection. If @option{listen} is
663 specified, QEMU waits for incoming connections on @var{port}
664 (@var{host} is optional). @option{connect} is used to connect to
665 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
666 specifies an already opened TCP socket.
670 # launch a first QEMU instance
671 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
672 -net socket,listen=:1234
673 # connect the VLAN 0 of this instance to the VLAN 0
674 # of the first instance
675 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
676 -net socket,connect=127.0.0.1:1234
679 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}]
681 Create a VLAN @var{n} shared with another QEMU virtual
682 machines using a UDP multicast socket, effectively making a bus for
683 every QEMU with same multicast address @var{maddr} and @var{port}.
687 Several QEMU can be running on different hosts and share same bus (assuming
688 correct multicast setup for these hosts).
690 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
691 @url{http://user-mode-linux.sf.net}.
693 Use @option{fd=h} to specify an already opened UDP multicast socket.
698 # launch one QEMU instance
699 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
700 -net socket,mcast=230.0.0.1:1234
701 # launch another QEMU instance on same "bus"
702 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
703 -net socket,mcast=230.0.0.1:1234
704 # launch yet another QEMU instance on same "bus"
705 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
706 -net socket,mcast=230.0.0.1:1234
709 Example (User Mode Linux compat.):
711 # launch QEMU instance (note mcast address selected
713 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
714 -net socket,mcast=239.192.168.1:1102
716 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
719 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
720 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
721 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
722 and MODE @var{octalmode} to change default ownership and permissions for
723 communication port. This option is available only if QEMU has been compiled
724 with vde support enabled.
729 vde_switch -F -sock /tmp/myswitch
730 # launch QEMU instance
731 qemu linux.img -net nic -net vde,sock=/tmp/myswitch
735 Indicate that no network devices should be configured. It is used to
736 override the default configuration (@option{-net nic -net user}) which
737 is activated if no @option{-net} options are provided.
739 @item -tftp @var{dir}
740 When using the user mode network stack, activate a built-in TFTP
741 server. The files in @var{dir} will be exposed as the root of a TFTP server.
742 The TFTP client on the guest must be configured in binary mode (use the command
743 @code{bin} of the Unix TFTP client). The host IP address on the guest is as
746 @item -bootp @var{file}
747 When using the user mode network stack, broadcast @var{file} as the BOOTP
748 filename. In conjunction with @option{-tftp}, this can be used to network boot
749 a guest from a local directory.
751 Example (using pxelinux):
753 qemu -hda linux.img -boot n -tftp /path/to/tftp/files -bootp /pxelinux.0
757 When using the user mode network stack, activate a built-in SMB
758 server so that Windows OSes can access to the host files in @file{@var{dir}}
761 In the guest Windows OS, the line:
765 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
766 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
768 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
770 Note that a SAMBA server must be installed on the host OS in
771 @file{/usr/sbin/smbd}. QEMU was tested successfully with smbd version
772 2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core 3.
774 @item -redir [tcp|udp]:@var{host-port}:[@var{guest-host}]:@var{guest-port}
776 When using the user mode network stack, redirect incoming TCP or UDP
777 connections to the host port @var{host-port} to the guest
778 @var{guest-host} on guest port @var{guest-port}. If @var{guest-host}
779 is not specified, its value is 10.0.2.15 (default address given by the
780 built-in DHCP server).
782 For example, to redirect host X11 connection from screen 1 to guest
783 screen 0, use the following:
787 qemu -redir tcp:6001::6000 [...]
788 # this host xterm should open in the guest X11 server
792 To redirect telnet connections from host port 5555 to telnet port on
793 the guest, use the following:
797 qemu -redir tcp:5555::23 [...]
798 telnet localhost 5555
801 Then when you use on the host @code{telnet localhost 5555}, you
802 connect to the guest telnet server.
806 Bluetooth(R) options:
810 Defines the function of the corresponding Bluetooth HCI. -bt options
811 are matched with the HCIs present in the chosen machine type. For
812 example when emulating a machine with only one HCI built into it, only
813 the first @code{-bt hci[...]} option is valid and defines the HCI's
814 logic. The Transport Layer is decided by the machine type. Currently
815 the machines @code{n800} and @code{n810} have one HCI and all other
819 The following three types are recognized:
823 (default) The corresponding Bluetooth HCI assumes no internal logic
824 and will not respond to any HCI commands or emit events.
826 @item -bt hci,host[:@var{id}]
827 (@code{bluez} only) The corresponding HCI passes commands / events
828 to / from the physical HCI identified by the name @var{id} (default:
829 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
830 capable systems like Linux.
832 @item -bt hci[,vlan=@var{n}]
833 Add a virtual, standard HCI that will participate in the Bluetooth
834 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
835 VLANs, devices inside a bluetooth network @var{n} can only communicate
836 with other devices in the same network (scatternet).
839 @item -bt vhci[,vlan=@var{n}]
840 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
841 to the host bluetooth stack instead of to the emulated target. This
842 allows the host and target machines to participate in a common scatternet
843 and communicate. Requires the Linux @code{vhci} driver installed. Can
844 be used as following:
847 qemu [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
850 @item -bt device:@var{dev}[,vlan=@var{n}]
851 Emulate a bluetooth device @var{dev} and place it in network @var{n}
852 (default @code{0}). QEMU can only emulate one type of bluetooth devices
857 Virtual wireless keyboard implementing the HIDP bluetooth profile.
862 Linux boot specific: When using these options, you can use a given
863 Linux kernel without installing it in the disk image. It can be useful
864 for easier testing of various kernels.
868 @item -kernel @var{bzImage}
869 Use @var{bzImage} as kernel image.
871 @item -append @var{cmdline}
872 Use @var{cmdline} as kernel command line
874 @item -initrd @var{file}
875 Use @var{file} as initial ram disk.
879 Debug/Expert options:
882 @item -serial @var{dev}
883 Redirect the virtual serial port to host character device
884 @var{dev}. The default device is @code{vc} in graphical mode and
885 @code{stdio} in non graphical mode.
887 This option can be used several times to simulate up to 4 serials
890 Use @code{-serial none} to disable all serial ports.
892 Available character devices are:
895 Virtual console. Optionally, a width and height can be given in pixel with
899 It is also possible to specify width or height in characters:
904 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
906 No device is allocated.
910 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
911 parameters are set according to the emulated ones.
912 @item /dev/parport@var{N}
913 [Linux only, parallel port only] Use host parallel port
914 @var{N}. Currently SPP and EPP parallel port features can be used.
915 @item file:@var{filename}
916 Write output to @var{filename}. No character can be read.
918 [Unix only] standard input/output
919 @item pipe:@var{filename}
920 name pipe @var{filename}
922 [Windows only] Use host serial port @var{n}
923 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
924 This implements UDP Net Console.
925 When @var{remote_host} or @var{src_ip} are not specified
926 they default to @code{0.0.0.0}.
927 When not using a specified @var{src_port} a random port is automatically chosen.
929 If you just want a simple readonly console you can use @code{netcat} or
930 @code{nc}, by starting qemu with: @code{-serial udp::4555} and nc as:
931 @code{nc -u -l -p 4555}. Any time qemu writes something to that port it
932 will appear in the netconsole session.
934 If you plan to send characters back via netconsole or you want to stop
935 and start qemu a lot of times, you should have qemu use the same
936 source port each time by using something like @code{-serial
937 udp::4555@@:4556} to qemu. Another approach is to use a patched
938 version of netcat which can listen to a TCP port and send and receive
939 characters via udp. If you have a patched version of netcat which
940 activates telnet remote echo and single char transfer, then you can
941 use the following options to step up a netcat redirector to allow
942 telnet on port 5555 to access the qemu port.
945 -serial udp::4555@@:4556
946 @item netcat options:
947 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
948 @item telnet options:
953 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
954 The TCP Net Console has two modes of operation. It can send the serial
955 I/O to a location or wait for a connection from a location. By default
956 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
957 the @var{server} option QEMU will wait for a client socket application
958 to connect to the port before continuing, unless the @code{nowait}
959 option was specified. The @code{nodelay} option disables the Nagle buffering
960 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
961 one TCP connection at a time is accepted. You can use @code{telnet} to
962 connect to the corresponding character device.
964 @item Example to send tcp console to 192.168.0.2 port 4444
965 -serial tcp:192.168.0.2:4444
966 @item Example to listen and wait on port 4444 for connection
967 -serial tcp::4444,server
968 @item Example to not wait and listen on ip 192.168.0.100 port 4444
969 -serial tcp:192.168.0.100:4444,server,nowait
972 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
973 The telnet protocol is used instead of raw tcp sockets. The options
974 work the same as if you had specified @code{-serial tcp}. The
975 difference is that the port acts like a telnet server or client using
976 telnet option negotiation. This will also allow you to send the
977 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
978 sequence. Typically in unix telnet you do it with Control-] and then
979 type "send break" followed by pressing the enter key.
981 @item unix:@var{path}[,server][,nowait]
982 A unix domain socket is used instead of a tcp socket. The option works the
983 same as if you had specified @code{-serial tcp} except the unix domain socket
984 @var{path} is used for connections.
986 @item mon:@var{dev_string}
987 This is a special option to allow the monitor to be multiplexed onto
988 another serial port. The monitor is accessed with key sequence of
989 @key{Control-a} and then pressing @key{c}. See monitor access
990 @ref{pcsys_keys} in the -nographic section for more keys.
991 @var{dev_string} should be any one of the serial devices specified
992 above. An example to multiplex the monitor onto a telnet server
993 listening on port 4444 would be:
995 @item -serial mon:telnet::4444,server,nowait
999 Braille device. This will use BrlAPI to display the braille output on a real
1004 @item -parallel @var{dev}
1005 Redirect the virtual parallel port to host device @var{dev} (same
1006 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
1007 be used to use hardware devices connected on the corresponding host
1010 This option can be used several times to simulate up to 3 parallel
1013 Use @code{-parallel none} to disable all parallel ports.
1015 @item -monitor @var{dev}
1016 Redirect the monitor to host device @var{dev} (same devices as the
1018 The default device is @code{vc} in graphical mode and @code{stdio} in
1021 @item -echr numeric_ascii_value
1022 Change the escape character used for switching to the monitor when using
1023 monitor and serial sharing. The default is @code{0x01} when using the
1024 @code{-nographic} option. @code{0x01} is equal to pressing
1025 @code{Control-a}. You can select a different character from the ascii
1026 control keys where 1 through 26 map to Control-a through Control-z. For
1027 instance you could use the either of the following to change the escape
1028 character to Control-t.
1035 Wait gdb connection to port 1234 (@pxref{gdb_usage}).
1037 Change gdb connection port. @var{port} can be either a decimal number
1038 to specify a TCP port, or a host device (same devices as the serial port).
1040 Do not start CPU at startup (you must type 'c' in the monitor).
1042 Output log in /tmp/qemu.log
1043 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
1044 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
1045 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
1046 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
1047 all those parameters. This option is useful for old MS-DOS disk
1051 Set the directory for the BIOS, VGA BIOS and keymaps.
1053 @item -vga @var{type}
1054 Select type of VGA card to emulate. Valid values for @var{type} are
1057 Cirrus Logic GD5446 Video card. All Windows versions starting from
1058 Windows 95 should recognize and use this graphic card. For optimal
1059 performances, use 16 bit color depth in the guest and the host OS.
1060 (This one is the default)
1062 Standard VGA card with Bochs VBE extensions. If your guest OS
1063 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1064 to use high resolution modes (>= 1280x1024x16) then you should use
1067 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1068 recent XFree86/XOrg server or Windows guest with a driver for this
1073 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1074 it if your guest OS complains about ACPI problems (PC target machine
1078 Exit instead of rebooting.
1081 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
1082 This allows for instance switching to monitor to commit changes to the
1086 Start right away with a saved state (@code{loadvm} in monitor)
1089 Enable semihosting syscall emulation (ARM and M68K target machines only).
1091 On ARM this implements the "Angel" interface.
1092 On M68K this implements the "ColdFire GDB" interface used by libgloss.
1094 Note that this allows guest direct access to the host filesystem,
1095 so should only be used with trusted guest OS.
1097 @item -icount [N|auto]
1098 Enable virtual instruction counter. The virtual cpu will execute one
1099 instruction every 2^N ns of virtual time. If @code{auto} is specified
1100 then the virtual cpu speed will be automatically adjusted to keep virtual
1101 time within a few seconds of real time.
1103 Note that while this option can give deterministic behavior, it does not
1104 provide cycle accurate emulation. Modern CPUs contain superscalar out of
1105 order cores with complex cache hierarchies. The number of instructions
1106 executed often has little or no correlation with actual performance.
1114 @c man begin OPTIONS
1116 During the graphical emulation, you can use the following keys:
1122 Switch to virtual console 'n'. Standard console mappings are:
1125 Target system display
1133 Toggle mouse and keyboard grab.
1136 In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
1137 @key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
1139 During emulation, if you are using the @option{-nographic} option, use
1140 @key{Ctrl-a h} to get terminal commands:
1148 Save disk data back to file (if -snapshot)
1150 toggle console timestamps
1152 Send break (magic sysrq in Linux)
1154 Switch between console and monitor
1162 @c man begin SEEALSO
1163 The HTML documentation of QEMU for more precise information and Linux
1164 user mode emulator invocation.
1174 @section QEMU Monitor
1176 The QEMU monitor is used to give complex commands to the QEMU
1177 emulator. You can use it to:
1182 Remove or insert removable media images
1183 (such as CD-ROM or floppies).
1186 Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
1189 @item Inspect the VM state without an external debugger.
1193 @subsection Commands
1195 The following commands are available:
1199 @item help or ? [@var{cmd}]
1200 Show the help for all commands or just for command @var{cmd}.
1203 Commit changes to the disk images (if -snapshot is used).
1205 @item info @var{subcommand}
1206 Show various information about the system state.
1210 show the various VLANs and the associated devices
1212 show the block devices
1213 @item info registers
1214 show the cpu registers
1216 show the command line history
1218 show emulated PCI device
1220 show USB devices plugged on the virtual USB hub
1222 show all USB host devices
1224 show information about active capturing
1225 @item info snapshots
1226 show list of VM snapshots
1228 show which guest mouse is receiving events
1234 @item eject [-f] @var{device}
1235 Eject a removable medium (use -f to force it).
1237 @item change @var{device} @var{setting}
1239 Change the configuration of a device.
1242 @item change @var{diskdevice} @var{filename}
1243 Change the medium for a removable disk device to point to @var{filename}. eg
1246 (qemu) change ide1-cd0 /path/to/some.iso
1249 @item change vnc @var{display},@var{options}
1250 Change the configuration of the VNC server. The valid syntax for @var{display}
1251 and @var{options} are described at @ref{sec_invocation}. eg
1254 (qemu) change vnc localhost:1
1257 @item change vnc password [@var{password}]
1259 Change the password associated with the VNC server. If the new password is not
1260 supplied, the monitor will prompt for it to be entered. VNC passwords are only
1261 significant up to 8 letters. eg
1264 (qemu) change vnc password
1270 @item screendump @var{filename}
1271 Save screen into PPM image @var{filename}.
1273 @item mouse_move @var{dx} @var{dy} [@var{dz}]
1274 Move the active mouse to the specified coordinates @var{dx} @var{dy}
1275 with optional scroll axis @var{dz}.
1277 @item mouse_button @var{val}
1278 Change the active mouse button state @var{val} (1=L, 2=M, 4=R).
1280 @item mouse_set @var{index}
1281 Set which mouse device receives events at given @var{index}, index
1282 can be obtained with
1287 @item wavcapture @var{filename} [@var{frequency} [@var{bits} [@var{channels}]]]
1288 Capture audio into @var{filename}. Using sample rate @var{frequency}
1289 bits per sample @var{bits} and number of channels @var{channels}.
1293 @item Sample rate = 44100 Hz - CD quality
1295 @item Number of channels = 2 - Stereo
1298 @item stopcapture @var{index}
1299 Stop capture with a given @var{index}, index can be obtained with
1304 @item log @var{item1}[,...]
1305 Activate logging of the specified items to @file{/tmp/qemu.log}.
1307 @item savevm [@var{tag}|@var{id}]
1308 Create a snapshot of the whole virtual machine. If @var{tag} is
1309 provided, it is used as human readable identifier. If there is already
1310 a snapshot with the same tag or ID, it is replaced. More info at
1313 @item loadvm @var{tag}|@var{id}
1314 Set the whole virtual machine to the snapshot identified by the tag
1315 @var{tag} or the unique snapshot ID @var{id}.
1317 @item delvm @var{tag}|@var{id}
1318 Delete the snapshot identified by @var{tag} or @var{id}.
1326 @item gdbserver [@var{port}]
1327 Start gdbserver session (default @var{port}=1234)
1329 @item x/fmt @var{addr}
1330 Virtual memory dump starting at @var{addr}.
1332 @item xp /@var{fmt} @var{addr}
1333 Physical memory dump starting at @var{addr}.
1335 @var{fmt} is a format which tells the command how to format the
1336 data. Its syntax is: @option{/@{count@}@{format@}@{size@}}
1340 is the number of items to be dumped.
1343 can be x (hex), d (signed decimal), u (unsigned decimal), o (octal),
1344 c (char) or i (asm instruction).
1347 can be b (8 bits), h (16 bits), w (32 bits) or g (64 bits). On x86,
1348 @code{h} or @code{w} can be specified with the @code{i} format to
1349 respectively select 16 or 32 bit code instruction size.
1356 Dump 10 instructions at the current instruction pointer:
1361 0x90107065: lea 0x0(%esi,1),%esi
1362 0x90107069: lea 0x0(%edi,1),%edi
1364 0x90107071: jmp 0x90107080
1372 Dump 80 16 bit values at the start of the video memory.
1374 (qemu) xp/80hx 0xb8000
1375 0x000b8000: 0x0b50 0x0b6c 0x0b65 0x0b78 0x0b38 0x0b36 0x0b2f 0x0b42
1376 0x000b8010: 0x0b6f 0x0b63 0x0b68 0x0b73 0x0b20 0x0b56 0x0b47 0x0b41
1377 0x000b8020: 0x0b42 0x0b69 0x0b6f 0x0b73 0x0b20 0x0b63 0x0b75 0x0b72
1378 0x000b8030: 0x0b72 0x0b65 0x0b6e 0x0b74 0x0b2d 0x0b63 0x0b76 0x0b73
1379 0x000b8040: 0x0b20 0x0b30 0x0b35 0x0b20 0x0b4e 0x0b6f 0x0b76 0x0b20
1380 0x000b8050: 0x0b32 0x0b30 0x0b30 0x0b33 0x0720 0x0720 0x0720 0x0720
1381 0x000b8060: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1382 0x000b8070: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1383 0x000b8080: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1384 0x000b8090: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
1388 @item p or print/@var{fmt} @var{expr}
1390 Print expression value. Only the @var{format} part of @var{fmt} is
1393 @item sendkey @var{keys}
1395 Send @var{keys} to the emulator. @var{keys} could be the name of the
1396 key or @code{#} followed by the raw value in either decimal or hexadecimal
1397 format. Use @code{-} to press several keys simultaneously. Example:
1402 This command is useful to send keys that your graphical user interface
1403 intercepts at low level, such as @code{ctrl-alt-f1} in X Window.
1409 @item boot_set @var{bootdevicelist}
1411 Define new values for the boot device list. Those values will override
1412 the values specified on the command line through the @code{-boot} option.
1414 The values that can be specified here depend on the machine type, but are
1415 the same that can be specified in the @code{-boot} command line option.
1417 @item usb_add @var{devname}
1419 Add the USB device @var{devname}. For details of available devices see
1422 @item usb_del @var{devname}
1424 Remove the USB device @var{devname} from the QEMU virtual USB
1425 hub. @var{devname} has the syntax @code{bus.addr}. Use the monitor
1426 command @code{info usb} to see the devices you can remove.
1430 @subsection Integer expressions
1432 The monitor understands integers expressions for every integer
1433 argument. You can use register names to get the value of specifics
1434 CPU registers by prefixing them with @emph{$}.
1437 @section Disk Images
1439 Since version 0.6.1, QEMU supports many disk image formats, including
1440 growable disk images (their size increase as non empty sectors are
1441 written), compressed and encrypted disk images. Version 0.8.3 added
1442 the new qcow2 disk image format which is essential to support VM
1446 * disk_images_quickstart:: Quick start for disk image creation
1447 * disk_images_snapshot_mode:: Snapshot mode
1448 * vm_snapshots:: VM snapshots
1449 * qemu_img_invocation:: qemu-img Invocation
1450 * qemu_nbd_invocation:: qemu-nbd Invocation
1451 * host_drives:: Using host drives
1452 * disk_images_fat_images:: Virtual FAT disk images
1453 * disk_images_nbd:: NBD access
1456 @node disk_images_quickstart
1457 @subsection Quick start for disk image creation
1459 You can create a disk image with the command:
1461 qemu-img create myimage.img mysize
1463 where @var{myimage.img} is the disk image filename and @var{mysize} is its
1464 size in kilobytes. You can add an @code{M} suffix to give the size in
1465 megabytes and a @code{G} suffix for gigabytes.
1467 See @ref{qemu_img_invocation} for more information.
1469 @node disk_images_snapshot_mode
1470 @subsection Snapshot mode
1472 If you use the option @option{-snapshot}, all disk images are
1473 considered as read only. When sectors in written, they are written in
1474 a temporary file created in @file{/tmp}. You can however force the
1475 write back to the raw disk images by using the @code{commit} monitor
1476 command (or @key{C-a s} in the serial console).
1479 @subsection VM snapshots
1481 VM snapshots are snapshots of the complete virtual machine including
1482 CPU state, RAM, device state and the content of all the writable
1483 disks. In order to use VM snapshots, you must have at least one non
1484 removable and writable block device using the @code{qcow2} disk image
1485 format. Normally this device is the first virtual hard drive.
1487 Use the monitor command @code{savevm} to create a new VM snapshot or
1488 replace an existing one. A human readable name can be assigned to each
1489 snapshot in addition to its numerical ID.
1491 Use @code{loadvm} to restore a VM snapshot and @code{delvm} to remove
1492 a VM snapshot. @code{info snapshots} lists the available snapshots
1493 with their associated information:
1496 (qemu) info snapshots
1497 Snapshot devices: hda
1498 Snapshot list (from hda):
1499 ID TAG VM SIZE DATE VM CLOCK
1500 1 start 41M 2006-08-06 12:38:02 00:00:14.954
1501 2 40M 2006-08-06 12:43:29 00:00:18.633
1502 3 msys 40M 2006-08-06 12:44:04 00:00:23.514
1505 A VM snapshot is made of a VM state info (its size is shown in
1506 @code{info snapshots}) and a snapshot of every writable disk image.
1507 The VM state info is stored in the first @code{qcow2} non removable
1508 and writable block device. The disk image snapshots are stored in
1509 every disk image. The size of a snapshot in a disk image is difficult
1510 to evaluate and is not shown by @code{info snapshots} because the
1511 associated disk sectors are shared among all the snapshots to save
1512 disk space (otherwise each snapshot would need a full copy of all the
1515 When using the (unrelated) @code{-snapshot} option
1516 (@ref{disk_images_snapshot_mode}), you can always make VM snapshots,
1517 but they are deleted as soon as you exit QEMU.
1519 VM snapshots currently have the following known limitations:
1522 They cannot cope with removable devices if they are removed or
1523 inserted after a snapshot is done.
1525 A few device drivers still have incomplete snapshot support so their
1526 state is not saved or restored properly (in particular USB).
1529 @node qemu_img_invocation
1530 @subsection @code{qemu-img} Invocation
1532 @include qemu-img.texi
1534 @node qemu_nbd_invocation
1535 @subsection @code{qemu-nbd} Invocation
1537 @include qemu-nbd.texi
1540 @subsection Using host drives
1542 In addition to disk image files, QEMU can directly access host
1543 devices. We describe here the usage for QEMU version >= 0.8.3.
1545 @subsubsection Linux
1547 On Linux, you can directly use the host device filename instead of a
1548 disk image filename provided you have enough privileges to access
1549 it. For example, use @file{/dev/cdrom} to access to the CDROM or
1550 @file{/dev/fd0} for the floppy.
1554 You can specify a CDROM device even if no CDROM is loaded. QEMU has
1555 specific code to detect CDROM insertion or removal. CDROM ejection by
1556 the guest OS is supported. Currently only data CDs are supported.
1558 You can specify a floppy device even if no floppy is loaded. Floppy
1559 removal is currently not detected accurately (if you change floppy
1560 without doing floppy access while the floppy is not loaded, the guest
1561 OS will think that the same floppy is loaded).
1563 Hard disks can be used. Normally you must specify the whole disk
1564 (@file{/dev/hdb} instead of @file{/dev/hdb1}) so that the guest OS can
1565 see it as a partitioned disk. WARNING: unless you know what you do, it
1566 is better to only make READ-ONLY accesses to the hard disk otherwise
1567 you may corrupt your host data (use the @option{-snapshot} command
1568 line option or modify the device permissions accordingly).
1571 @subsubsection Windows
1575 The preferred syntax is the drive letter (e.g. @file{d:}). The
1576 alternate syntax @file{\\.\d:} is supported. @file{/dev/cdrom} is
1577 supported as an alias to the first CDROM drive.
1579 Currently there is no specific code to handle removable media, so it
1580 is better to use the @code{change} or @code{eject} monitor commands to
1581 change or eject media.
1583 Hard disks can be used with the syntax: @file{\\.\PhysicalDrive@var{N}}
1584 where @var{N} is the drive number (0 is the first hard disk).
1586 WARNING: unless you know what you do, it is better to only make
1587 READ-ONLY accesses to the hard disk otherwise you may corrupt your
1588 host data (use the @option{-snapshot} command line so that the
1589 modifications are written in a temporary file).
1593 @subsubsection Mac OS X
1595 @file{/dev/cdrom} is an alias to the first CDROM.
1597 Currently there is no specific code to handle removable media, so it
1598 is better to use the @code{change} or @code{eject} monitor commands to
1599 change or eject media.
1601 @node disk_images_fat_images
1602 @subsection Virtual FAT disk images
1604 QEMU can automatically create a virtual FAT disk image from a
1605 directory tree. In order to use it, just type:
1608 qemu linux.img -hdb fat:/my_directory
1611 Then you access access to all the files in the @file{/my_directory}
1612 directory without having to copy them in a disk image or to export
1613 them via SAMBA or NFS. The default access is @emph{read-only}.
1615 Floppies can be emulated with the @code{:floppy:} option:
1618 qemu linux.img -fda fat:floppy:/my_directory
1621 A read/write support is available for testing (beta stage) with the
1625 qemu linux.img -fda fat:floppy:rw:/my_directory
1628 What you should @emph{never} do:
1630 @item use non-ASCII filenames ;
1631 @item use "-snapshot" together with ":rw:" ;
1632 @item expect it to work when loadvm'ing ;
1633 @item write to the FAT directory on the host system while accessing it with the guest system.
1636 @node disk_images_nbd
1637 @subsection NBD access
1639 QEMU can access directly to block device exported using the Network Block Device
1643 qemu linux.img -hdb nbd:my_nbd_server.mydomain.org:1024
1646 If the NBD server is located on the same host, you can use an unix socket instead
1650 qemu linux.img -hdb nbd:unix:/tmp/my_socket
1653 In this case, the block device must be exported using qemu-nbd:
1656 qemu-nbd --socket=/tmp/my_socket my_disk.qcow2
1659 The use of qemu-nbd allows to share a disk between several guests:
1661 qemu-nbd --socket=/tmp/my_socket --share=2 my_disk.qcow2
1664 and then you can use it with two guests:
1666 qemu linux1.img -hdb nbd:unix:/tmp/my_socket
1667 qemu linux2.img -hdb nbd:unix:/tmp/my_socket
1671 @section Network emulation
1673 QEMU can simulate several network cards (PCI or ISA cards on the PC
1674 target) and can connect them to an arbitrary number of Virtual Local
1675 Area Networks (VLANs). Host TAP devices can be connected to any QEMU
1676 VLAN. VLAN can be connected between separate instances of QEMU to
1677 simulate large networks. For simpler usage, a non privileged user mode
1678 network stack can replace the TAP device to have a basic network
1683 QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
1684 connection between several network devices. These devices can be for
1685 example QEMU virtual Ethernet cards or virtual Host ethernet devices
1688 @subsection Using TAP network interfaces
1690 This is the standard way to connect QEMU to a real network. QEMU adds
1691 a virtual network device on your host (called @code{tapN}), and you
1692 can then configure it as if it was a real ethernet card.
1694 @subsubsection Linux host
1696 As an example, you can download the @file{linux-test-xxx.tar.gz}
1697 archive and copy the script @file{qemu-ifup} in @file{/etc} and
1698 configure properly @code{sudo} so that the command @code{ifconfig}
1699 contained in @file{qemu-ifup} can be executed as root. You must verify
1700 that your host kernel supports the TAP network interfaces: the
1701 device @file{/dev/net/tun} must be present.
1703 See @ref{sec_invocation} to have examples of command lines using the
1704 TAP network interfaces.
1706 @subsubsection Windows host
1708 There is a virtual ethernet driver for Windows 2000/XP systems, called
1709 TAP-Win32. But it is not included in standard QEMU for Windows,
1710 so you will need to get it separately. It is part of OpenVPN package,
1711 so download OpenVPN from : @url{http://openvpn.net/}.
1713 @subsection Using the user mode network stack
1715 By using the option @option{-net user} (default configuration if no
1716 @option{-net} option is specified), QEMU uses a completely user mode
1717 network stack (you don't need root privilege to use the virtual
1718 network). The virtual network configuration is the following:
1722 QEMU VLAN <------> Firewall/DHCP server <-----> Internet
1725 ----> DNS server (10.0.2.3)
1727 ----> SMB server (10.0.2.4)
1730 The QEMU VM behaves as if it was behind a firewall which blocks all
1731 incoming connections. You can use a DHCP client to automatically
1732 configure the network in the QEMU VM. The DHCP server assign addresses
1733 to the hosts starting from 10.0.2.15.
1735 In order to check that the user mode network is working, you can ping
1736 the address 10.0.2.2 and verify that you got an address in the range
1737 10.0.2.x from the QEMU virtual DHCP server.
1739 Note that @code{ping} is not supported reliably to the internet as it
1740 would require root privileges. It means you can only ping the local
1743 When using the built-in TFTP server, the router is also the TFTP
1746 When using the @option{-redir} option, TCP or UDP connections can be
1747 redirected from the host to the guest. It allows for example to
1748 redirect X11, telnet or SSH connections.
1750 @subsection Connecting VLANs between QEMU instances
1752 Using the @option{-net socket} option, it is possible to make VLANs
1753 that span several QEMU instances. See @ref{sec_invocation} to have a
1756 @node direct_linux_boot
1757 @section Direct Linux Boot
1759 This section explains how to launch a Linux kernel inside QEMU without
1760 having to make a full bootable image. It is very useful for fast Linux
1765 qemu -kernel arch/i386/boot/bzImage -hda root-2.4.20.img -append "root=/dev/hda"
1768 Use @option{-kernel} to provide the Linux kernel image and
1769 @option{-append} to give the kernel command line arguments. The
1770 @option{-initrd} option can be used to provide an INITRD image.
1772 When using the direct Linux boot, a disk image for the first hard disk
1773 @file{hda} is required because its boot sector is used to launch the
1776 If you do not need graphical output, you can disable it and redirect
1777 the virtual serial port and the QEMU monitor to the console with the
1778 @option{-nographic} option. The typical command line is:
1780 qemu -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1781 -append "root=/dev/hda console=ttyS0" -nographic
1784 Use @key{Ctrl-a c} to switch between the serial console and the
1785 monitor (@pxref{pcsys_keys}).
1788 @section USB emulation
1790 QEMU emulates a PCI UHCI USB controller. You can virtually plug
1791 virtual USB devices or real host USB devices (experimental, works only
1792 on Linux hosts). Qemu will automatically create and connect virtual USB hubs
1793 as necessary to connect multiple USB devices.
1797 * host_usb_devices::
1800 @subsection Connecting USB devices
1802 USB devices can be connected with the @option{-usbdevice} commandline option
1803 or the @code{usb_add} monitor command. Available devices are:
1807 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1809 Pointer device that uses absolute coordinates (like a touchscreen).
1810 This means qemu is able to report the mouse position without having
1811 to grab the mouse. Also overrides the PS/2 mouse emulation when activated.
1812 @item disk:@var{file}
1813 Mass storage device based on @var{file} (@pxref{disk_images})
1814 @item host:@var{bus.addr}
1815 Pass through the host device identified by @var{bus.addr}
1817 @item host:@var{vendor_id:product_id}
1818 Pass through the host device identified by @var{vendor_id:product_id}
1821 Virtual Wacom PenPartner tablet. This device is similar to the @code{tablet}
1822 above but it can be used with the tslib library because in addition to touch
1823 coordinates it reports touch pressure.
1825 Standard USB keyboard. Will override the PS/2 keyboard (if present).
1826 @item serial:[vendorid=@var{vendor_id}][,product_id=@var{product_id}]:@var{dev}
1827 Serial converter. This emulates an FTDI FT232BM chip connected to host character
1828 device @var{dev}. The available character devices are the same as for the
1829 @code{-serial} option. The @code{vendorid} and @code{productid} options can be
1830 used to override the default 0403:6001. For instance,
1832 usb_add serial:productid=FA00:tcp:192.168.0.2:4444
1834 will connect to tcp port 4444 of ip 192.168.0.2, and plug that to the virtual
1835 serial converter, faking a Matrix Orbital LCD Display (USB ID 0403:FA00).
1837 Braille device. This will use BrlAPI to display the braille output on a real
1839 @item net:@var{options}
1840 Network adapter that supports CDC ethernet and RNDIS protocols. @var{options}
1841 specifies NIC options as with @code{-net nic,}@var{options} (see description).
1842 For instance, user-mode networking can be used with
1844 qemu [...OPTIONS...] -net user,vlan=0 -usbdevice net:vlan=0
1846 Currently this cannot be used in machines that support PCI NICs.
1847 @item bt[:@var{hci-type}]
1848 Bluetooth dongle whose type is specified in the same format as with
1849 the @option{-bt hci} option, @pxref{bt-hcis,,allowed HCI types}. If
1850 no type is given, the HCI logic corresponds to @code{-bt hci,vlan=0}.
1851 This USB device implements the USB Transport Layer of HCI. Example
1854 qemu [...OPTIONS...] -usbdevice bt:hci,vlan=3 -bt device:keyboard,vlan=3
1858 @node host_usb_devices
1859 @subsection Using host USB devices on a Linux host
1861 WARNING: this is an experimental feature. QEMU will slow down when
1862 using it. USB devices requiring real time streaming (i.e. USB Video
1863 Cameras) are not supported yet.
1866 @item If you use an early Linux 2.4 kernel, verify that no Linux driver
1867 is actually using the USB device. A simple way to do that is simply to
1868 disable the corresponding kernel module by renaming it from @file{mydriver.o}
1869 to @file{mydriver.o.disabled}.
1871 @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
1877 @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:
1879 chown -R myuid /proc/bus/usb
1882 @item Launch QEMU and do in the monitor:
1885 Device 1.2, speed 480 Mb/s
1886 Class 00: USB device 1234:5678, USB DISK
1888 You should see the list of the devices you can use (Never try to use
1889 hubs, it won't work).
1891 @item Add the device in QEMU by using:
1893 usb_add host:1234:5678
1896 Normally the guest OS should report that a new USB device is
1897 plugged. You can use the option @option{-usbdevice} to do the same.
1899 @item Now you can try to use the host USB device in QEMU.
1903 When relaunching QEMU, you may have to unplug and plug again the USB
1904 device to make it work again (this is a bug).
1907 @section VNC security
1909 The VNC server capability provides access to the graphical console
1910 of the guest VM across the network. This has a number of security
1911 considerations depending on the deployment scenarios.
1915 * vnc_sec_password::
1916 * vnc_sec_certificate::
1917 * vnc_sec_certificate_verify::
1918 * vnc_sec_certificate_pw::
1919 * vnc_generate_cert::
1922 @subsection Without passwords
1924 The simplest VNC server setup does not include any form of authentication.
1925 For this setup it is recommended to restrict it to listen on a UNIX domain
1926 socket only. For example
1929 qemu [...OPTIONS...] -vnc unix:/home/joebloggs/.qemu-myvm-vnc
1932 This ensures that only users on local box with read/write access to that
1933 path can access the VNC server. To securely access the VNC server from a
1934 remote machine, a combination of netcat+ssh can be used to provide a secure
1937 @node vnc_sec_password
1938 @subsection With passwords
1940 The VNC protocol has limited support for password based authentication. Since
1941 the protocol limits passwords to 8 characters it should not be considered
1942 to provide high security. The password can be fairly easily brute-forced by
1943 a client making repeat connections. For this reason, a VNC server using password
1944 authentication should be restricted to only listen on the loopback interface
1945 or UNIX domain sockets. Password authentication is requested with the @code{password}
1946 option, and then once QEMU is running the password is set with the monitor. Until
1947 the monitor is used to set the password all clients will be rejected.
1950 qemu [...OPTIONS...] -vnc :1,password -monitor stdio
1951 (qemu) change vnc password
1956 @node vnc_sec_certificate
1957 @subsection With x509 certificates
1959 The QEMU VNC server also implements the VeNCrypt extension allowing use of
1960 TLS for encryption of the session, and x509 certificates for authentication.
1961 The use of x509 certificates is strongly recommended, because TLS on its
1962 own is susceptible to man-in-the-middle attacks. Basic x509 certificate
1963 support provides a secure session, but no authentication. This allows any
1964 client to connect, and provides an encrypted session.
1967 qemu [...OPTIONS...] -vnc :1,tls,x509=/etc/pki/qemu -monitor stdio
1970 In the above example @code{/etc/pki/qemu} should contain at least three files,
1971 @code{ca-cert.pem}, @code{server-cert.pem} and @code{server-key.pem}. Unprivileged
1972 users will want to use a private directory, for example @code{$HOME/.pki/qemu}.
1973 NB the @code{server-key.pem} file should be protected with file mode 0600 to
1974 only be readable by the user owning it.
1976 @node vnc_sec_certificate_verify
1977 @subsection With x509 certificates and client verification
1979 Certificates can also provide a means to authenticate the client connecting.
1980 The server will request that the client provide a certificate, which it will
1981 then validate against the CA certificate. This is a good choice if deploying
1982 in an environment with a private internal certificate authority.
1985 qemu [...OPTIONS...] -vnc :1,tls,x509verify=/etc/pki/qemu -monitor stdio
1989 @node vnc_sec_certificate_pw
1990 @subsection With x509 certificates, client verification and passwords
1992 Finally, the previous method can be combined with VNC password authentication
1993 to provide two layers of authentication for clients.
1996 qemu [...OPTIONS...] -vnc :1,password,tls,x509verify=/etc/pki/qemu -monitor stdio
1997 (qemu) change vnc password
2002 @node vnc_generate_cert
2003 @subsection Generating certificates for VNC
2005 The GNU TLS packages provides a command called @code{certtool} which can
2006 be used to generate certificates and keys in PEM format. At a minimum it
2007 is neccessary to setup a certificate authority, and issue certificates to
2008 each server. If using certificates for authentication, then each client
2009 will also need to be issued a certificate. The recommendation is for the
2010 server to keep its certificates in either @code{/etc/pki/qemu} or for
2011 unprivileged users in @code{$HOME/.pki/qemu}.
2015 * vnc_generate_server::
2016 * vnc_generate_client::
2018 @node vnc_generate_ca
2019 @subsubsection Setup the Certificate Authority
2021 This step only needs to be performed once per organization / organizational
2022 unit. First the CA needs a private key. This key must be kept VERY secret
2023 and secure. If this key is compromised the entire trust chain of the certificates
2024 issued with it is lost.
2027 # certtool --generate-privkey > ca-key.pem
2030 A CA needs to have a public certificate. For simplicity it can be a self-signed
2031 certificate, or one issue by a commercial certificate issuing authority. To
2032 generate a self-signed certificate requires one core piece of information, the
2033 name of the organization.
2036 # cat > ca.info <<EOF
2037 cn = Name of your organization
2041 # certtool --generate-self-signed \
2042 --load-privkey ca-key.pem
2043 --template ca.info \
2044 --outfile ca-cert.pem
2047 The @code{ca-cert.pem} file should be copied to all servers and clients wishing to utilize
2048 TLS support in the VNC server. The @code{ca-key.pem} must not be disclosed/copied at all.
2050 @node vnc_generate_server
2051 @subsubsection Issuing server certificates
2053 Each server (or host) needs to be issued with a key and certificate. When connecting
2054 the certificate is sent to the client which validates it against the CA certificate.
2055 The core piece of information for a server certificate is the hostname. This should
2056 be the fully qualified hostname that the client will connect with, since the client
2057 will typically also verify the hostname in the certificate. On the host holding the
2058 secure CA private key:
2061 # cat > server.info <<EOF
2062 organization = Name of your organization
2063 cn = server.foo.example.com
2068 # certtool --generate-privkey > server-key.pem
2069 # certtool --generate-certificate \
2070 --load-ca-certificate ca-cert.pem \
2071 --load-ca-privkey ca-key.pem \
2072 --load-privkey server server-key.pem \
2073 --template server.info \
2074 --outfile server-cert.pem
2077 The @code{server-key.pem} and @code{server-cert.pem} files should now be securely copied
2078 to the server for which they were generated. The @code{server-key.pem} is security
2079 sensitive and should be kept protected with file mode 0600 to prevent disclosure.
2081 @node vnc_generate_client
2082 @subsubsection Issuing client certificates
2084 If the QEMU VNC server is to use the @code{x509verify} option to validate client
2085 certificates as its authentication mechanism, each client also needs to be issued
2086 a certificate. The client certificate contains enough metadata to uniquely identify
2087 the client, typically organization, state, city, building, etc. On the host holding
2088 the secure CA private key:
2091 # cat > client.info <<EOF
2095 organiazation = Name of your organization
2096 cn = client.foo.example.com
2101 # certtool --generate-privkey > client-key.pem
2102 # certtool --generate-certificate \
2103 --load-ca-certificate ca-cert.pem \
2104 --load-ca-privkey ca-key.pem \
2105 --load-privkey client-key.pem \
2106 --template client.info \
2107 --outfile client-cert.pem
2110 The @code{client-key.pem} and @code{client-cert.pem} files should now be securely
2111 copied to the client for which they were generated.
2116 QEMU has a primitive support to work with gdb, so that you can do
2117 'Ctrl-C' while the virtual machine is running and inspect its state.
2119 In order to use gdb, launch qemu with the '-s' option. It will wait for a
2122 > qemu -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
2123 -append "root=/dev/hda"
2124 Connected to host network interface: tun0
2125 Waiting gdb connection on port 1234
2128 Then launch gdb on the 'vmlinux' executable:
2133 In gdb, connect to QEMU:
2135 (gdb) target remote localhost:1234
2138 Then you can use gdb normally. For example, type 'c' to launch the kernel:
2143 Here are some useful tips in order to use gdb on system code:
2147 Use @code{info reg} to display all the CPU registers.
2149 Use @code{x/10i $eip} to display the code at the PC position.
2151 Use @code{set architecture i8086} to dump 16 bit code. Then use
2152 @code{x/10i $cs*16+$eip} to dump the code at the PC position.
2155 Advanced debugging options:
2157 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:
2159 @item maintenance packet qqemu.sstepbits
2161 This will display the MASK bits used to control the single stepping IE:
2163 (gdb) maintenance packet qqemu.sstepbits
2164 sending: "qqemu.sstepbits"
2165 received: "ENABLE=1,NOIRQ=2,NOTIMER=4"
2167 @item maintenance packet qqemu.sstep
2169 This will display the current value of the mask used when single stepping IE:
2171 (gdb) maintenance packet qqemu.sstep
2172 sending: "qqemu.sstep"
2175 @item maintenance packet Qqemu.sstep=HEX_VALUE
2177 This will change the single step mask, so if wanted to enable IRQs on the single step, but not timers, you would use:
2179 (gdb) maintenance packet Qqemu.sstep=0x5
2180 sending: "qemu.sstep=0x5"
2185 @node pcsys_os_specific
2186 @section Target OS specific information
2190 To have access to SVGA graphic modes under X11, use the @code{vesa} or
2191 the @code{cirrus} X11 driver. For optimal performances, use 16 bit
2192 color depth in the guest and the host OS.
2194 When using a 2.6 guest Linux kernel, you should add the option
2195 @code{clock=pit} on the kernel command line because the 2.6 Linux
2196 kernels make very strict real time clock checks by default that QEMU
2197 cannot simulate exactly.
2199 When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
2200 not activated because QEMU is slower with this patch. The QEMU
2201 Accelerator Module is also much slower in this case. Earlier Fedora
2202 Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporate this
2203 patch by default. Newer kernels don't have it.
2207 If you have a slow host, using Windows 95 is better as it gives the
2208 best speed. Windows 2000 is also a good choice.
2210 @subsubsection SVGA graphic modes support
2212 QEMU emulates a Cirrus Logic GD5446 Video
2213 card. All Windows versions starting from Windows 95 should recognize
2214 and use this graphic card. For optimal performances, use 16 bit color
2215 depth in the guest and the host OS.
2217 If you are using Windows XP as guest OS and if you want to use high
2218 resolution modes which the Cirrus Logic BIOS does not support (i.e. >=
2219 1280x1024x16), then you should use the VESA VBE virtual graphic card
2220 (option @option{-std-vga}).
2222 @subsubsection CPU usage reduction
2224 Windows 9x does not correctly use the CPU HLT
2225 instruction. The result is that it takes host CPU cycles even when
2226 idle. You can install the utility from
2227 @url{http://www.user.cityline.ru/~maxamn/amnhltm.zip} to solve this
2228 problem. Note that no such tool is needed for NT, 2000 or XP.
2230 @subsubsection Windows 2000 disk full problem
2232 Windows 2000 has a bug which gives a disk full problem during its
2233 installation. When installing it, use the @option{-win2k-hack} QEMU
2234 option to enable a specific workaround. After Windows 2000 is
2235 installed, you no longer need this option (this option slows down the
2238 @subsubsection Windows 2000 shutdown
2240 Windows 2000 cannot automatically shutdown in QEMU although Windows 98
2241 can. It comes from the fact that Windows 2000 does not automatically
2242 use the APM driver provided by the BIOS.
2244 In order to correct that, do the following (thanks to Struan
2245 Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
2246 Add/Troubleshoot a device => Add a new device & Next => No, select the
2247 hardware from a list & Next => NT Apm/Legacy Support & Next => Next
2248 (again) a few times. Now the driver is installed and Windows 2000 now
2249 correctly instructs QEMU to shutdown at the appropriate moment.
2251 @subsubsection Share a directory between Unix and Windows
2253 See @ref{sec_invocation} about the help of the option @option{-smb}.
2255 @subsubsection Windows XP security problem
2257 Some releases of Windows XP install correctly but give a security
2260 A problem is preventing Windows from accurately checking the
2261 license for this computer. Error code: 0x800703e6.
2264 The workaround is to install a service pack for XP after a boot in safe
2265 mode. Then reboot, and the problem should go away. Since there is no
2266 network while in safe mode, its recommended to download the full
2267 installation of SP1 or SP2 and transfer that via an ISO or using the
2268 vvfat block device ("-hdb fat:directory_which_holds_the_SP").
2270 @subsection MS-DOS and FreeDOS
2272 @subsubsection CPU usage reduction
2274 DOS does not correctly use the CPU HLT instruction. The result is that
2275 it takes host CPU cycles even when idle. You can install the utility
2276 from @url{http://www.vmware.com/software/dosidle210.zip} to solve this
2279 @node QEMU System emulator for non PC targets
2280 @chapter QEMU System emulator for non PC targets
2282 QEMU is a generic emulator and it emulates many non PC
2283 machines. Most of the options are similar to the PC emulator. The
2284 differences are mentioned in the following sections.
2287 * QEMU PowerPC System emulator::
2288 * Sparc32 System emulator::
2289 * Sparc64 System emulator::
2290 * MIPS System emulator::
2291 * ARM System emulator::
2292 * ColdFire System emulator::
2295 @node QEMU PowerPC System emulator
2296 @section QEMU PowerPC System emulator
2298 Use the executable @file{qemu-system-ppc} to simulate a complete PREP
2299 or PowerMac PowerPC system.
2301 QEMU emulates the following PowerMac peripherals:
2307 PCI VGA compatible card with VESA Bochs Extensions
2309 2 PMAC IDE interfaces with hard disk and CD-ROM support
2315 VIA-CUDA with ADB keyboard and mouse.
2318 QEMU emulates the following PREP peripherals:
2324 PCI VGA compatible card with VESA Bochs Extensions
2326 2 IDE interfaces with hard disk and CD-ROM support
2330 NE2000 network adapters
2334 PREP Non Volatile RAM
2336 PC compatible keyboard and mouse.
2339 QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS available at
2340 @url{http://perso.magic.fr/l_indien/OpenHackWare/index.htm}.
2342 Since version 0.9.1, QEMU uses OpenBIOS @url{http://www.openbios.org/}
2343 for the g3beige PowerMac machine. OpenBIOS is a free (GPL v2) portable
2344 firmware implementation. The goal is to implement a 100% IEEE
2345 1275-1994 (referred to as Open Firmware) compliant firmware.
2347 @c man begin OPTIONS
2349 The following options are specific to the PowerPC emulation:
2353 @item -g WxH[xDEPTH]
2355 Set the initial VGA graphic mode. The default is 800x600x15.
2357 @item -prom-env string
2359 Set OpenBIOS variables in NVRAM, for example:
2362 qemu-system-ppc -prom-env 'auto-boot?=false' \
2363 -prom-env 'boot-device=hd:2,\yaboot' \
2364 -prom-env 'boot-args=conf=hd:2,\yaboot.conf'
2367 These variables are not used by Open Hack'Ware.
2374 More information is available at
2375 @url{http://perso.magic.fr/l_indien/qemu-ppc/}.
2377 @node Sparc32 System emulator
2378 @section Sparc32 System emulator
2380 Use the executable @file{qemu-system-sparc} to simulate the following
2381 Sun4m architecture machines:
2396 SPARCstation Voyager
2403 The emulation is somewhat complete. SMP up to 16 CPUs is supported,
2404 but Linux limits the number of usable CPUs to 4.
2406 It's also possible to simulate a SPARCstation 2 (sun4c architecture),
2407 SPARCserver 1000, or SPARCcenter 2000 (sun4d architecture), but these
2408 emulators are not usable yet.
2410 QEMU emulates the following sun4m/sun4c/sun4d peripherals:
2418 Lance (Am7990) Ethernet
2420 Non Volatile RAM M48T02/M48T08
2422 Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
2423 and power/reset logic
2425 ESP SCSI controller with hard disk and CD-ROM support
2427 Floppy drive (not on SS-600MP)
2429 CS4231 sound device (only on SS-5, not working yet)
2432 The number of peripherals is fixed in the architecture. Maximum
2433 memory size depends on the machine type, for SS-5 it is 256MB and for
2436 Since version 0.8.2, QEMU uses OpenBIOS
2437 @url{http://www.openbios.org/}. OpenBIOS is a free (GPL v2) portable
2438 firmware implementation. The goal is to implement a 100% IEEE
2439 1275-1994 (referred to as Open Firmware) compliant firmware.
2441 A sample Linux 2.6 series kernel and ram disk image are available on
2442 the QEMU web site. There are still issues with NetBSD and OpenBSD, but
2443 some kernel versions work. Please note that currently Solaris kernels
2444 don't work probably due to interface issues between OpenBIOS and
2447 @c man begin OPTIONS
2449 The following options are specific to the Sparc32 emulation:
2453 @item -g WxHx[xDEPTH]
2455 Set the initial TCX graphic mode. The default is 1024x768x8, currently
2456 the only other possible mode is 1024x768x24.
2458 @item -prom-env string
2460 Set OpenBIOS variables in NVRAM, for example:
2463 qemu-system-sparc -prom-env 'auto-boot?=false' \
2464 -prom-env 'boot-device=sd(0,2,0):d' -prom-env 'boot-args=linux single'
2467 @item -M [SS-4|SS-5|SS-10|SS-20|SS-600MP|LX|Voyager|SPARCClassic|SPARCbook|SS-2|SS-1000|SS-2000]
2469 Set the emulated machine type. Default is SS-5.
2475 @node Sparc64 System emulator
2476 @section Sparc64 System emulator
2478 Use the executable @file{qemu-system-sparc64} to simulate a Sun4u
2479 (UltraSPARC PC-like machine), Sun4v (T1 PC-like machine), or generic
2480 Niagara (T1) machine. The emulator is not usable for anything yet, but
2481 it can launch some kernels.
2483 QEMU emulates the following peripherals:
2487 UltraSparc IIi APB PCI Bridge
2489 PCI VGA compatible card with VESA Bochs Extensions
2491 PS/2 mouse and keyboard
2493 Non Volatile RAM M48T59
2495 PC-compatible serial ports
2497 2 PCI IDE interfaces with hard disk and CD-ROM support
2502 @c man begin OPTIONS
2504 The following options are specific to the Sparc64 emulation:
2508 @item -prom-env string
2510 Set OpenBIOS variables in NVRAM, for example:
2513 qemu-system-sparc64 -prom-env 'auto-boot?=false'
2516 @item -M [sun4u|sun4v|Niagara]
2518 Set the emulated machine type. The default is sun4u.
2524 @node MIPS System emulator
2525 @section MIPS System emulator
2527 Four executables cover simulation of 32 and 64-bit MIPS systems in
2528 both endian options, @file{qemu-system-mips}, @file{qemu-system-mipsel}
2529 @file{qemu-system-mips64} and @file{qemu-system-mips64el}.
2530 Five different machine types are emulated:
2534 A generic ISA PC-like machine "mips"
2536 The MIPS Malta prototype board "malta"
2538 An ACER Pica "pica61". This machine needs the 64-bit emulator.
2540 MIPS emulator pseudo board "mipssim"
2542 A MIPS Magnum R4000 machine "magnum". This machine needs the 64-bit emulator.
2545 The generic emulation is supported by Debian 'Etch' and is able to
2546 install Debian into a virtual disk image. The following devices are
2551 A range of MIPS CPUs, default is the 24Kf
2553 PC style serial port
2560 The Malta emulation supports the following devices:
2564 Core board with MIPS 24Kf CPU and Galileo system controller
2566 PIIX4 PCI/USB/SMbus controller
2568 The Multi-I/O chip's serial device
2570 PCnet32 PCI network card
2572 Malta FPGA serial device
2574 Cirrus VGA graphics card
2577 The ACER Pica emulation supports:
2583 PC-style IRQ and DMA controllers
2590 The mipssim pseudo board emulation provides an environment similiar
2591 to what the proprietary MIPS emulator uses for running Linux.
2596 A range of MIPS CPUs, default is the 24Kf
2598 PC style serial port
2600 MIPSnet network emulation
2603 The MIPS Magnum R4000 emulation supports:
2609 PC-style IRQ controller
2619 @node ARM System emulator
2620 @section ARM System emulator
2622 Use the executable @file{qemu-system-arm} to simulate a ARM
2623 machine. The ARM Integrator/CP board is emulated with the following
2628 ARM926E, ARM1026E, ARM946E, ARM1136 or Cortex-A8 CPU
2632 SMC 91c111 Ethernet adapter
2634 PL110 LCD controller
2636 PL050 KMI with PS/2 keyboard and mouse.
2638 PL181 MultiMedia Card Interface with SD card.
2641 The ARM Versatile baseboard is emulated with the following devices:
2645 ARM926E, ARM1136 or Cortex-A8 CPU
2647 PL190 Vectored Interrupt Controller
2651 SMC 91c111 Ethernet adapter
2653 PL110 LCD controller
2655 PL050 KMI with PS/2 keyboard and mouse.
2657 PCI host bridge. Note the emulated PCI bridge only provides access to
2658 PCI memory space. It does not provide access to PCI IO space.
2659 This means some devices (eg. ne2k_pci NIC) are not usable, and others
2660 (eg. rtl8139 NIC) are only usable when the guest drivers use the memory
2661 mapped control registers.
2663 PCI OHCI USB controller.
2665 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices.
2667 PL181 MultiMedia Card Interface with SD card.
2670 The ARM RealView Emulation baseboard is emulated with the following devices:
2674 ARM926E, ARM1136, ARM11MPCORE(x4) or Cortex-A8 CPU
2676 ARM AMBA Generic/Distributed Interrupt Controller
2680 SMC 91c111 Ethernet adapter
2682 PL110 LCD controller
2684 PL050 KMI with PS/2 keyboard and mouse
2688 PCI OHCI USB controller
2690 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices
2692 PL181 MultiMedia Card Interface with SD card.
2695 The XScale-based clamshell PDA models ("Spitz", "Akita", "Borzoi"
2696 and "Terrier") emulation includes the following peripherals:
2700 Intel PXA270 System-on-chip (ARM V5TE core)
2704 IBM/Hitachi DSCM microdrive in a PXA PCMCIA slot - not in "Akita"
2706 On-chip OHCI USB controller
2708 On-chip LCD controller
2710 On-chip Real Time Clock
2712 TI ADS7846 touchscreen controller on SSP bus
2714 Maxim MAX1111 analog-digital converter on I@math{^2}C bus
2716 GPIO-connected keyboard controller and LEDs
2718 Secure Digital card connected to PXA MMC/SD host
2722 WM8750 audio CODEC on I@math{^2}C and I@math{^2}S busses
2725 The Palm Tungsten|E PDA (codename "Cheetah") emulation includes the
2730 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
2732 ROM and RAM memories (ROM firmware image can be loaded with -option-rom)
2734 On-chip LCD controller
2736 On-chip Real Time Clock
2738 TI TSC2102i touchscreen controller / analog-digital converter / Audio
2739 CODEC, connected through MicroWire and I@math{^2}S busses
2741 GPIO-connected matrix keypad
2743 Secure Digital card connected to OMAP MMC/SD host
2748 Nokia N800 and N810 internet tablets (known also as RX-34 and RX-44 / 48)
2749 emulation supports the following elements:
2753 Texas Instruments OMAP2420 System-on-chip (ARM 1136 core)
2755 RAM and non-volatile OneNAND Flash memories
2757 Display connected to EPSON remote framebuffer chip and OMAP on-chip
2758 display controller and a LS041y3 MIPI DBI-C controller
2760 TI TSC2301 (in N800) and TI TSC2005 (in N810) touchscreen controllers
2761 driven through SPI bus
2763 National Semiconductor LM8323-controlled qwerty keyboard driven
2764 through I@math{^2}C bus
2766 Secure Digital card connected to OMAP MMC/SD host
2768 Three OMAP on-chip UARTs and on-chip STI debugging console
2770 A Bluetooth(R) transciever and HCI connected to an UART
2772 Mentor Graphics "Inventra" dual-role USB controller embedded in a TI
2773 TUSB6010 chip - only USB host mode is supported
2775 TI TMP105 temperature sensor driven through I@math{^2}C bus
2777 TI TWL92230C power management companion with an RTC on I@math{^2}C bus
2779 Nokia RETU and TAHVO multi-purpose chips with an RTC, connected
2783 The Luminary Micro Stellaris LM3S811EVB emulation includes the following
2790 64k Flash and 8k SRAM.
2792 Timers, UARTs, ADC and I@math{^2}C interface.
2794 OSRAM Pictiva 96x16 OLED with SSD0303 controller on I@math{^2}C bus.
2797 The Luminary Micro Stellaris LM3S6965EVB emulation includes the following
2804 256k Flash and 64k SRAM.
2806 Timers, UARTs, ADC, I@math{^2}C and SSI interfaces.
2808 OSRAM Pictiva 128x64 OLED with SSD0323 controller connected via SSI.
2811 The Freecom MusicPal internet radio emulation includes the following
2816 Marvell MV88W8618 ARM core.
2818 32 MB RAM, 256 KB SRAM, 8 MB flash.
2822 MV88W8xx8 Ethernet controller
2824 MV88W8618 audio controller, WM8750 CODEC and mixer
2826 128×64 display with brightness control
2828 2 buttons, 2 navigation wheels with button function
2831 The Siemens SX1 models v1 and v2 (default) basic emulation.
2832 The emulaton includes the following elements:
2836 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
2838 ROM and RAM memories (ROM firmware image can be loaded with -pflash)
2840 1 Flash of 16MB and 1 Flash of 8MB
2844 On-chip LCD controller
2846 On-chip Real Time Clock
2848 Secure Digital card connected to OMAP MMC/SD host
2853 A Linux 2.6 test image is available on the QEMU web site. More
2854 information is available in the QEMU mailing-list archive.
2856 @node ColdFire System emulator
2857 @section ColdFire System emulator
2859 Use the executable @file{qemu-system-m68k} to simulate a ColdFire machine.
2860 The emulator is able to boot a uClinux kernel.
2862 The M5208EVB emulation includes the following devices:
2866 MCF5208 ColdFire V2 Microprocessor (ISA A+ with EMAC).
2868 Three Two on-chip UARTs.
2870 Fast Ethernet Controller (FEC)
2873 The AN5206 emulation includes the following devices:
2877 MCF5206 ColdFire V2 Microprocessor.
2882 @node QEMU User space emulator
2883 @chapter QEMU User space emulator
2886 * Supported Operating Systems ::
2887 * Linux User space emulator::
2888 * Mac OS X/Darwin User space emulator ::
2889 * BSD User space emulator ::
2892 @node Supported Operating Systems
2893 @section Supported Operating Systems
2895 The following OS are supported in user space emulation:
2899 Linux (referred as qemu-linux-user)
2901 Mac OS X/Darwin (referred as qemu-darwin-user)
2903 BSD (referred as qemu-bsd-user)
2906 @node Linux User space emulator
2907 @section Linux User space emulator
2912 * Command line options::
2917 @subsection Quick Start
2919 In order to launch a Linux process, QEMU needs the process executable
2920 itself and all the target (x86) dynamic libraries used by it.
2924 @item On x86, you can just try to launch any process by using the native
2928 qemu-i386 -L / /bin/ls
2931 @code{-L /} tells that the x86 dynamic linker must be searched with a
2934 @item Since QEMU is also a linux process, you can launch qemu with
2935 qemu (NOTE: you can only do that if you compiled QEMU from the sources):
2938 qemu-i386 -L / qemu-i386 -L / /bin/ls
2941 @item On non x86 CPUs, you need first to download at least an x86 glibc
2942 (@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
2943 @code{LD_LIBRARY_PATH} is not set:
2946 unset LD_LIBRARY_PATH
2949 Then you can launch the precompiled @file{ls} x86 executable:
2952 qemu-i386 tests/i386/ls
2954 You can look at @file{qemu-binfmt-conf.sh} so that
2955 QEMU is automatically launched by the Linux kernel when you try to
2956 launch x86 executables. It requires the @code{binfmt_misc} module in the
2959 @item The x86 version of QEMU is also included. You can try weird things such as:
2961 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 \
2962 /usr/local/qemu-i386/bin/ls-i386
2968 @subsection Wine launch
2972 @item Ensure that you have a working QEMU with the x86 glibc
2973 distribution (see previous section). In order to verify it, you must be
2977 qemu-i386 /usr/local/qemu-i386/bin/ls-i386
2980 @item Download the binary x86 Wine install
2981 (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
2983 @item Configure Wine on your account. Look at the provided script
2984 @file{/usr/local/qemu-i386/@/bin/wine-conf.sh}. Your previous
2985 @code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
2987 @item Then you can try the example @file{putty.exe}:
2990 qemu-i386 /usr/local/qemu-i386/wine/bin/wine \
2991 /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
2996 @node Command line options
2997 @subsection Command line options
3000 usage: qemu-i386 [-h] [-d] [-L path] [-s size] [-cpu model] [-g port] program [arguments...]
3007 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
3009 Set the x86 stack size in bytes (default=524288)
3011 Select CPU model (-cpu ? for list and additional feature selection)
3018 Activate log (logfile=/tmp/qemu.log)
3020 Act as if the host page size was 'pagesize' bytes
3022 Wait gdb connection to port
3025 Environment variables:
3029 Print system calls and arguments similar to the 'strace' program
3030 (NOTE: the actual 'strace' program will not work because the user
3031 space emulator hasn't implemented ptrace). At the moment this is
3032 incomplete. All system calls that don't have a specific argument
3033 format are printed with information for six arguments. Many
3034 flag-style arguments don't have decoders and will show up as numbers.
3037 @node Other binaries
3038 @subsection Other binaries
3040 @command{qemu-arm} is also capable of running ARM "Angel" semihosted ELF
3041 binaries (as implemented by the arm-elf and arm-eabi Newlib/GDB
3042 configurations), and arm-uclinux bFLT format binaries.
3044 @command{qemu-m68k} is capable of running semihosted binaries using the BDM
3045 (m5xxx-ram-hosted.ld) or m68k-sim (sim.ld) syscall interfaces, and
3046 coldfire uClinux bFLT format binaries.
3048 The binary format is detected automatically.
3050 @command{qemu-sparc} can execute Sparc32 binaries (Sparc32 CPU, 32 bit ABI).
3052 @command{qemu-sparc32plus} can execute Sparc32 and SPARC32PLUS binaries
3053 (Sparc64 CPU, 32 bit ABI).
3055 @command{qemu-sparc64} can execute some Sparc64 (Sparc64 CPU, 64 bit ABI) and
3056 SPARC32PLUS binaries (Sparc64 CPU, 32 bit ABI).
3058 @node Mac OS X/Darwin User space emulator
3059 @section Mac OS X/Darwin User space emulator
3062 * Mac OS X/Darwin Status::
3063 * Mac OS X/Darwin Quick Start::
3064 * Mac OS X/Darwin Command line options::
3067 @node Mac OS X/Darwin Status
3068 @subsection Mac OS X/Darwin Status
3072 target x86 on x86: Most apps (Cocoa and Carbon too) works. [1]
3074 target PowerPC on x86: Not working as the ppc commpage can't be mapped (yet!)
3076 target PowerPC on PowerPC: Most apps (Cocoa and Carbon too) works. [1]
3078 target x86 on PowerPC: most utilities work. Cocoa and Carbon apps are not yet supported.
3081 [1] If you're host commpage can be executed by qemu.
3083 @node Mac OS X/Darwin Quick Start
3084 @subsection Quick Start
3086 In order to launch a Mac OS X/Darwin process, QEMU needs the process executable
3087 itself and all the target dynamic libraries used by it. If you don't have the FAT
3088 libraries (you're running Mac OS X/ppc) you'll need to obtain it from a Mac OS X
3089 CD or compile them by hand.
3093 @item On x86, you can just try to launch any process by using the native
3100 or to run the ppc version of the executable:
3106 @item On ppc, you'll have to tell qemu where your x86 libraries (and dynamic linker)
3110 qemu-i386 -L /opt/x86_root/ /bin/ls
3113 @code{-L /opt/x86_root/} tells that the dynamic linker (dyld) path is in
3114 @file{/opt/x86_root/usr/bin/dyld}.
3118 @node Mac OS X/Darwin Command line options
3119 @subsection Command line options
3122 usage: qemu-i386 [-h] [-d] [-L path] [-s size] program [arguments...]
3129 Set the library root path (default=/)
3131 Set the stack size in bytes (default=524288)
3138 Activate log (logfile=/tmp/qemu.log)
3140 Act as if the host page size was 'pagesize' bytes
3143 @node BSD User space emulator
3144 @section BSD User space emulator
3149 * BSD Command line options::
3153 @subsection BSD Status
3157 target Sparc64 on Sparc64: Some trivial programs work.
3160 @node BSD Quick Start
3161 @subsection Quick Start
3163 In order to launch a BSD process, QEMU needs the process executable
3164 itself and all the target dynamic libraries used by it.
3168 @item On Sparc64, you can just try to launch any process by using the native
3172 qemu-sparc64 /bin/ls
3177 @node BSD Command line options
3178 @subsection Command line options
3181 usage: qemu-sparc64 [-h] [-d] [-L path] [-s size] [-bsd type] program [arguments...]
3188 Set the library root path (default=/)
3190 Set the stack size in bytes (default=524288)
3192 Set the type of the emulated BSD Operating system. Valid values are
3193 FreeBSD, NetBSD and OpenBSD (default).
3200 Activate log (logfile=/tmp/qemu.log)
3202 Act as if the host page size was 'pagesize' bytes
3206 @chapter Compilation from the sources
3211 * Cross compilation for Windows with Linux::
3218 @subsection Compilation
3220 First you must decompress the sources:
3223 tar zxvf qemu-x.y.z.tar.gz
3227 Then you configure QEMU and build it (usually no options are needed):
3233 Then type as root user:
3237 to install QEMU in @file{/usr/local}.
3239 @subsection GCC version
3241 In order to compile QEMU successfully, it is very important that you
3242 have the right tools. The most important one is gcc. On most hosts and
3243 in particular on x86 ones, @emph{gcc 4.x is not supported}. If your
3244 Linux distribution includes a gcc 4.x compiler, you can usually
3245 install an older version (it is invoked by @code{gcc32} or
3246 @code{gcc34}). The QEMU configure script automatically probes for
3247 these older versions so that usually you don't have to do anything.
3253 @item Install the current versions of MSYS and MinGW from
3254 @url{http://www.mingw.org/}. You can find detailed installation
3255 instructions in the download section and the FAQ.
3258 the MinGW development library of SDL 1.2.x
3259 (@file{SDL-devel-1.2.x-@/mingw32.tar.gz}) from
3260 @url{http://www.libsdl.org}. Unpack it in a temporary place, and
3261 unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
3262 directory. Edit the @file{sdl-config} script so that it gives the
3263 correct SDL directory when invoked.
3265 @item Extract the current version of QEMU.
3267 @item Start the MSYS shell (file @file{msys.bat}).
3269 @item Change to the QEMU directory. Launch @file{./configure} and
3270 @file{make}. If you have problems using SDL, verify that
3271 @file{sdl-config} can be launched from the MSYS command line.
3273 @item You can install QEMU in @file{Program Files/Qemu} by typing
3274 @file{make install}. Don't forget to copy @file{SDL.dll} in
3275 @file{Program Files/Qemu}.
3279 @node Cross compilation for Windows with Linux
3280 @section Cross compilation for Windows with Linux
3284 Install the MinGW cross compilation tools available at
3285 @url{http://www.mingw.org/}.
3288 Install the Win32 version of SDL (@url{http://www.libsdl.org}) by
3289 unpacking @file{i386-mingw32msvc.tar.gz}. Set up the PATH environment
3290 variable so that @file{i386-mingw32msvc-sdl-config} can be launched by
3291 the QEMU configuration script.
3294 Configure QEMU for Windows cross compilation:
3296 ./configure --enable-mingw32
3298 If necessary, you can change the cross-prefix according to the prefix
3299 chosen for the MinGW tools with --cross-prefix. You can also use
3300 --prefix to set the Win32 install path.
3302 @item You can install QEMU in the installation directory by typing
3303 @file{make install}. Don't forget to copy @file{SDL.dll} in the
3304 installation directory.
3308 Note: Currently, Wine does not seem able to launch
3314 The Mac OS X patches are not fully merged in QEMU, so you should look
3315 at the QEMU mailing list archive to have all the necessary