1 \input texinfo @c -*- texinfo -*-
3 @setfilename qemu-doc.info
4 @settitle QEMU CPU Emulator User Documentation
12 @center @titlefont{QEMU CPU Emulator}
14 @center @titlefont{User Documentation}
26 * QEMU PC System emulator::
27 * QEMU System emulator for non PC targets::
28 * QEMU Linux 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 (Linux host only). In this mode, QEMU can launch
61 Linux processes compiled for one CPU on another CPU. It can be used to
62 launch the Wine Windows API emulator (@url{http://www.winehq.org}) or
63 to ease cross-compilation and cross-debugging.
67 QEMU can run without an host kernel driver and yet gives acceptable
70 For system emulation, the following hardware targets are supported:
72 @item PC (x86 or x86_64 processor)
73 @item ISA PC (old style PC without PCI bus)
74 @item PREP (PowerPC processor)
75 @item G3 BW PowerMac (PowerPC processor)
76 @item Mac99 PowerMac (PowerPC processor, in progress)
77 @item Sun4m (32-bit Sparc processor)
78 @item Sun4u (64-bit Sparc processor, in progress)
79 @item Malta board (32-bit MIPS processor)
80 @item ARM Integrator/CP (ARM926E or 1026E processor)
81 @item ARM Versatile baseboard (ARM926E)
84 For user emulation, x86, PowerPC, ARM, MIPS, and Sparc32/64 CPUs are supported.
89 If you want to compile QEMU yourself, see @ref{compilation}.
92 * install_linux:: Linux
93 * install_windows:: Windows
94 * install_mac:: Macintosh
100 If a precompiled package is available for your distribution - you just
101 have to install it. Otherwise, see @ref{compilation}.
103 @node install_windows
106 Download the experimental binary installer at
107 @url{http://www.free.oszoo.org/@/download.html}.
112 Download the experimental binary installer at
113 @url{http://www.free.oszoo.org/@/download.html}.
115 @node QEMU PC System emulator
116 @chapter QEMU PC System emulator
119 * pcsys_introduction:: Introduction
120 * pcsys_quickstart:: Quick Start
121 * sec_invocation:: Invocation
123 * pcsys_monitor:: QEMU Monitor
124 * disk_images:: Disk Images
125 * pcsys_network:: Network emulation
126 * direct_linux_boot:: Direct Linux Boot
127 * pcsys_usb:: USB emulation
128 * gdb_usage:: GDB usage
129 * pcsys_os_specific:: Target OS specific information
132 @node pcsys_introduction
133 @section Introduction
135 @c man begin DESCRIPTION
137 The QEMU PC System emulator simulates the
138 following peripherals:
142 i440FX host PCI bridge and PIIX3 PCI to ISA bridge
144 Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
145 extensions (hardware level, including all non standard modes).
147 PS/2 mouse and keyboard
149 2 PCI IDE interfaces with hard disk and CD-ROM support
153 NE2000 PCI network adapters
157 Creative SoundBlaster 16 sound card
159 ENSONIQ AudioPCI ES1370 sound card
161 Adlib(OPL2) - Yamaha YM3812 compatible chip
163 PCI UHCI USB controller and a virtual USB hub.
166 SMP is supported with up to 255 CPUs.
168 Note that adlib is only available when QEMU was configured with
171 QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
174 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
178 @node pcsys_quickstart
181 Download and uncompress the linux image (@file{linux.img}) and type:
187 Linux should boot and give you a prompt.
193 @c man begin SYNOPSIS
194 usage: qemu [options] [disk_image]
199 @var{disk_image} is a raw hard disk image for IDE hard disk 0.
204 Select the emulated machine (@code{-M ?} for list)
208 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
209 use the host floppy by using @file{/dev/fd0} as filename.
215 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
218 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and and
219 @option{-cdrom} at the same time). You can use the host CD-ROM by
220 using @file{/dev/cdrom} as filename.
223 Boot on floppy (a), hard disk (c) or CD-ROM (d). Hard disk boot is
227 Write to temporary files instead of disk image files. In this case,
228 the raw disk image you use is not written back. You can however force
229 the write back by pressing @key{C-a s} (@pxref{disk_images}).
232 Set virtual RAM size to @var{megs} megabytes. Default is 128 MB.
235 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
240 Normally, QEMU uses SDL to display the VGA output. With this option,
241 you can totally disable graphical output so that QEMU is a simple
242 command line application. The emulated serial port is redirected on
243 the console. Therefore, you can still use QEMU to debug a Linux kernel
244 with a serial console.
248 Normally, QEMU uses SDL to display the VGA output. With this option,
249 you can have QEMU listen on VNC display d and redirect the VGA display
250 over the VNC session. It is very useful to enable the usb tablet device
251 when using this option (option @option{-usbdevice tablet}).
255 Use keyboard layout @var{language} (for example @code{fr} for
256 French). This option is only needed where it is not easy to get raw PC
257 keycodes (e.g. on Macs or with some X11 servers). You don't need to
258 use it on PC/Linux or PC/Windows hosts.
260 The available layouts are:
262 ar de-ch es fo fr-ca hu ja mk no pt-br sv
263 da en-gb et fr fr-ch is lt nl pl ru th
264 de en-us fi fr-be hr it lv nl-be pt sl tr
267 The default is @code{en-us}.
271 Will show the audio subsystem help: list of drivers, tunable
274 @item -soundhw card1,card2,... or -soundhw all
276 Enable audio and selected sound hardware. Use ? to print all
277 available sound hardware.
280 qemu -soundhw sb16,adlib hda
281 qemu -soundhw es1370 hda
282 qemu -soundhw all hda
287 Set the real time clock to local time (the default is to UTC
288 time). This option is needed to have correct date in MS-DOS or
292 Start in full screen.
295 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
299 Use it when installing Windows 2000 to avoid a disk full bug. After
300 Windows 2000 is installed, you no longer need this option (this option
301 slows down the IDE transfers).
309 Enable the USB driver (will be the default soon)
311 @item -usbdevice devname
312 Add the USB device @var{devname}. See the monitor command
313 @code{usb_add} to have more information.
320 @item -net nic[,vlan=n][,macaddr=addr][,model=type]
321 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
322 = 0 is the default). The NIC is currently an NE2000 on the PC
323 target. Optionally, the MAC address can be changed. If no
324 @option{-net} option is specified, a single NIC is created.
325 Qemu can emulate several different models of network card. Valid values for
326 @var{type} are @code{ne2k_pci}, @code{ne2k_isa}, @code{rtl8139},
327 @code{smc91c111} and @code{lance}. Not all devices are supported on all
330 @item -net user[,vlan=n][,hostname=name]
331 Use the user mode network stack which requires no administrator
332 priviledge to run. @option{hostname=name} can be used to specify the client
333 hostname reported by the builtin DHCP server.
335 @item -net tap[,vlan=n][,fd=h][,ifname=name][,script=file]
336 Connect the host TAP network interface @var{name} to VLAN @var{n} and
337 use the network script @var{file} to configure it. The default
338 network script is @file{/etc/qemu-ifup}. If @var{name} is not
339 provided, the OS automatically provides one. @option{fd=h} can be
340 used to specify the handle of an already opened host TAP interface. Example:
343 qemu linux.img -net nic -net tap
346 More complicated example (two NICs, each one connected to a TAP device)
348 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
349 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
353 @item -net socket[,vlan=n][,fd=h][,listen=[host]:port][,connect=host:port]
355 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
356 machine using a TCP socket connection. If @option{listen} is
357 specified, QEMU waits for incoming connections on @var{port}
358 (@var{host} is optional). @option{connect} is used to connect to
359 another QEMU instance using the @option{listen} option. @option{fd=h}
360 specifies an already opened TCP socket.
364 # launch a first QEMU instance
365 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
366 -net socket,listen=:1234
367 # connect the VLAN 0 of this instance to the VLAN 0
368 # of the first instance
369 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
370 -net socket,connect=127.0.0.1:1234
373 @item -net socket[,vlan=n][,fd=h][,mcast=maddr:port]
375 Create a VLAN @var{n} shared with another QEMU virtual
376 machines using a UDP multicast socket, effectively making a bus for
377 every QEMU with same multicast address @var{maddr} and @var{port}.
381 Several QEMU can be running on different hosts and share same bus (assuming
382 correct multicast setup for these hosts).
384 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
385 @url{http://user-mode-linux.sf.net}.
386 @item Use @option{fd=h} to specify an already opened UDP multicast socket.
391 # launch one QEMU instance
392 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
393 -net socket,mcast=230.0.0.1:1234
394 # launch another QEMU instance on same "bus"
395 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
396 -net socket,mcast=230.0.0.1:1234
397 # launch yet another QEMU instance on same "bus"
398 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
399 -net socket,mcast=230.0.0.1:1234
402 Example (User Mode Linux compat.):
404 # launch QEMU instance (note mcast address selected
406 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
407 -net socket,mcast=239.192.168.1:1102
409 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
413 Indicate that no network devices should be configured. It is used to
414 override the default configuration (@option{-net nic -net user}) which
415 is activated if no @option{-net} options are provided.
418 When using the user mode network stack, activate a built-in TFTP
419 server. All filenames beginning with @var{prefix} can be downloaded
420 from the host to the guest using a TFTP client. The TFTP client on the
421 guest must be configured in binary mode (use the command @code{bin} of
422 the Unix TFTP client). The host IP address on the guest is as usual
426 When using the user mode network stack, activate a built-in SMB
427 server so that Windows OSes can access to the host files in @file{dir}
430 In the guest Windows OS, the line:
434 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
435 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
437 Then @file{dir} can be accessed in @file{\\smbserver\qemu}.
439 Note that a SAMBA server must be installed on the host OS in
440 @file{/usr/sbin/smbd}. QEMU was tested succesfully with smbd version
441 2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core 3.
443 @item -redir [tcp|udp]:host-port:[guest-host]:guest-port
445 When using the user mode network stack, redirect incoming TCP or UDP
446 connections to the host port @var{host-port} to the guest
447 @var{guest-host} on guest port @var{guest-port}. If @var{guest-host}
448 is not specified, its value is 10.0.2.15 (default address given by the
449 built-in DHCP server).
451 For example, to redirect host X11 connection from screen 1 to guest
452 screen 0, use the following:
456 qemu -redir tcp:6001::6000 [...]
457 # this host xterm should open in the guest X11 server
461 To redirect telnet connections from host port 5555 to telnet port on
462 the guest, use the following:
466 qemu -redir tcp:5555::23 [...]
467 telnet localhost 5555
470 Then when you use on the host @code{telnet localhost 5555}, you
471 connect to the guest telnet server.
475 Linux boot specific: When using these options, you can use a given
476 Linux kernel without installing it in the disk image. It can be useful
477 for easier testing of various kernels.
481 @item -kernel bzImage
482 Use @var{bzImage} as kernel image.
484 @item -append cmdline
485 Use @var{cmdline} as kernel command line
488 Use @var{file} as initial ram disk.
492 Debug/Expert options:
496 Redirect the virtual serial port to host device @var{dev}. Available
502 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
506 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
507 parameters are set according to the emulated ones.
509 [Linux only, parallel port only] Use host parallel port
510 @var{N}. Currently only SPP parallel port features can be used.
512 Write output to filename. No character can be read.
514 [Unix only] standard input/output
516 [Unix only] name pipe @var{filename}
518 The default device is @code{vc} in graphical mode and @code{stdio} in
521 This option can be used several times to simulate up to 4 serials
525 Redirect the virtual parallel port to host device @var{dev} (same
526 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
527 be used to use hardware devices connected on the corresponding host
530 This option can be used several times to simulate up to 3 parallel
534 Redirect the monitor to host device @var{dev} (same devices as the
536 The default device is @code{vc} in graphical mode and @code{stdio} in
540 Wait gdb connection to port 1234 (@pxref{gdb_usage}).
542 Change gdb connection port.
544 Do not start CPU at startup (you must type 'c' in the monitor).
546 Output log in /tmp/qemu.log
547 @item -hdachs c,h,s,[,t]
548 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
549 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
550 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
551 all thoses parameters. This option is useful for old MS-DOS disk
555 Simulate a standard VGA card with Bochs VBE extensions (default is
556 Cirrus Logic GD5446 PCI VGA)
558 Start right away with a saved state (@code{loadvm} in monitor)
568 During the graphical emulation, you can use the following keys:
574 Switch to virtual console 'n'. Standard console mappings are:
577 Target system display
585 Toggle mouse and keyboard grab.
588 In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
589 @key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
591 During emulation, if you are using the @option{-nographic} option, use
592 @key{Ctrl-a h} to get terminal commands:
600 Save disk data back to file (if -snapshot)
602 Send break (magic sysrq in Linux)
604 Switch between console and monitor
613 The HTML documentation of QEMU for more precise information and Linux
614 user mode emulator invocation.
624 @section QEMU Monitor
626 The QEMU monitor is used to give complex commands to the QEMU
627 emulator. You can use it to:
632 Remove or insert removable medias images
633 (such as CD-ROM or floppies)
636 Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
639 @item Inspect the VM state without an external debugger.
645 The following commands are available:
649 @item help or ? [cmd]
650 Show the help for all commands or just for command @var{cmd}.
653 Commit changes to the disk images (if -snapshot is used)
655 @item info subcommand
656 show various information about the system state
660 show the various VLANs and the associated devices
662 show the block devices
664 show the cpu registers
666 show the command line history
668 show emulated PCI device
670 show USB devices plugged on the virtual USB hub
672 show all USB host devices
678 @item eject [-f] device
679 Eject a removable media (use -f to force it).
681 @item change device filename
682 Change a removable media.
684 @item screendump filename
685 Save screen into PPM image @var{filename}.
687 @item log item1[,...]
688 Activate logging of the specified items to @file{/tmp/qemu.log}.
690 @item savevm filename
691 Save the whole virtual machine state to @var{filename}.
693 @item loadvm filename
694 Restore the whole virtual machine state from @var{filename}.
702 @item gdbserver [port]
703 Start gdbserver session (default port=1234)
706 Virtual memory dump starting at @var{addr}.
709 Physical memory dump starting at @var{addr}.
711 @var{fmt} is a format which tells the command how to format the
712 data. Its syntax is: @option{/@{count@}@{format@}@{size@}}
716 is the number of items to be dumped.
719 can be x (hexa), d (signed decimal), u (unsigned decimal), o (octal),
720 c (char) or i (asm instruction).
723 can be b (8 bits), h (16 bits), w (32 bits) or g (64 bits). On x86,
724 @code{h} or @code{w} can be specified with the @code{i} format to
725 respectively select 16 or 32 bit code instruction size.
732 Dump 10 instructions at the current instruction pointer:
737 0x90107065: lea 0x0(%esi,1),%esi
738 0x90107069: lea 0x0(%edi,1),%edi
740 0x90107071: jmp 0x90107080
748 Dump 80 16 bit values at the start of the video memory.
750 (qemu) xp/80hx 0xb8000
751 0x000b8000: 0x0b50 0x0b6c 0x0b65 0x0b78 0x0b38 0x0b36 0x0b2f 0x0b42
752 0x000b8010: 0x0b6f 0x0b63 0x0b68 0x0b73 0x0b20 0x0b56 0x0b47 0x0b41
753 0x000b8020: 0x0b42 0x0b69 0x0b6f 0x0b73 0x0b20 0x0b63 0x0b75 0x0b72
754 0x000b8030: 0x0b72 0x0b65 0x0b6e 0x0b74 0x0b2d 0x0b63 0x0b76 0x0b73
755 0x000b8040: 0x0b20 0x0b30 0x0b35 0x0b20 0x0b4e 0x0b6f 0x0b76 0x0b20
756 0x000b8050: 0x0b32 0x0b30 0x0b30 0x0b33 0x0720 0x0720 0x0720 0x0720
757 0x000b8060: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
758 0x000b8070: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
759 0x000b8080: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
760 0x000b8090: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
764 @item p or print/fmt expr
766 Print expression value. Only the @var{format} part of @var{fmt} is
771 Send @var{keys} to the emulator. Use @code{-} to press several keys
772 simultaneously. Example:
777 This command is useful to send keys that your graphical user interface
778 intercepts at low level, such as @code{ctrl-alt-f1} in X Window.
784 @item usb_add devname
786 Plug the USB device devname to the QEMU virtual USB hub. @var{devname}
787 is either a virtual device name (for example @code{mouse}) or a host
788 USB device identifier. Host USB device identifiers have the following
789 syntax: @code{host:bus.addr} or @code{host:vendor_id:product_id}.
791 @item usb_del devname
793 Remove the USB device @var{devname} from the QEMU virtual USB
794 hub. @var{devname} has the syntax @code{bus.addr}. Use the monitor
795 command @code{info usb} to see the devices you can remove.
799 @subsection Integer expressions
801 The monitor understands integers expressions for every integer
802 argument. You can use register names to get the value of specifics
803 CPU registers by prefixing them with @emph{$}.
808 Since version 0.6.1, QEMU supports many disk image formats, including
809 growable disk images (their size increase as non empty sectors are
810 written), compressed and encrypted disk images.
813 * disk_images_quickstart:: Quick start for disk image creation
814 * disk_images_snapshot_mode:: Snapshot mode
815 * qemu_img_invocation:: qemu-img Invocation
816 * disk_images_fat_images:: Virtual FAT disk images
819 @node disk_images_quickstart
820 @subsection Quick start for disk image creation
822 You can create a disk image with the command:
824 qemu-img create myimage.img mysize
826 where @var{myimage.img} is the disk image filename and @var{mysize} is its
827 size in kilobytes. You can add an @code{M} suffix to give the size in
828 megabytes and a @code{G} suffix for gigabytes.
830 See @ref{qemu_img_invocation} for more information.
832 @node disk_images_snapshot_mode
833 @subsection Snapshot mode
835 If you use the option @option{-snapshot}, all disk images are
836 considered as read only. When sectors in written, they are written in
837 a temporary file created in @file{/tmp}. You can however force the
838 write back to the raw disk images by using the @code{commit} monitor
839 command (or @key{C-a s} in the serial console).
841 @node qemu_img_invocation
842 @subsection @code{qemu-img} Invocation
844 @include qemu-img.texi
846 @node disk_images_fat_images
847 @subsection Virtual FAT disk images
849 QEMU can automatically create a virtual FAT disk image from a
850 directory tree. In order to use it, just type:
853 qemu linux.img -hdb fat:/my_directory
856 Then you access access to all the files in the @file{/my_directory}
857 directory without having to copy them in a disk image or to export
858 them via SAMBA or NFS. The default access is @emph{read-only}.
860 Floppies can be emulated with the @code{:floppy:} option:
863 qemu linux.img -fda fat:floppy:/my_directory
866 A read/write support is available for testing (beta stage) with the
870 qemu linux.img -fda fat:floppy:rw:/my_directory
873 What you should @emph{never} do:
875 @item use non-ASCII filenames ;
876 @item use "-snapshot" together with ":rw:" ;
877 @item expect it to work when loadvm'ing ;
878 @item write to the FAT directory on the host system while accessing it with the guest system.
882 @section Network emulation
884 QEMU can simulate several networks cards (NE2000 boards on the PC
885 target) and can connect them to an arbitrary number of Virtual Local
886 Area Networks (VLANs). Host TAP devices can be connected to any QEMU
887 VLAN. VLAN can be connected between separate instances of QEMU to
888 simulate large networks. For simpler usage, a non priviledged user mode
889 network stack can replace the TAP device to have a basic network
894 QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
895 connection between several network devices. These devices can be for
896 example QEMU virtual Ethernet cards or virtual Host ethernet devices
899 @subsection Using TAP network interfaces
901 This is the standard way to connect QEMU to a real network. QEMU adds
902 a virtual network device on your host (called @code{tapN}), and you
903 can then configure it as if it was a real ethernet card.
905 As an example, you can download the @file{linux-test-xxx.tar.gz}
906 archive and copy the script @file{qemu-ifup} in @file{/etc} and
907 configure properly @code{sudo} so that the command @code{ifconfig}
908 contained in @file{qemu-ifup} can be executed as root. You must verify
909 that your host kernel supports the TAP network interfaces: the
910 device @file{/dev/net/tun} must be present.
912 See @ref{direct_linux_boot} to have an example of network use with a
913 Linux distribution and @ref{sec_invocation} to have examples of
914 command lines using the TAP network interfaces.
916 @subsection Using the user mode network stack
918 By using the option @option{-net user} (default configuration if no
919 @option{-net} option is specified), QEMU uses a completely user mode
920 network stack (you don't need root priviledge to use the virtual
921 network). The virtual network configuration is the following:
925 QEMU VLAN <------> Firewall/DHCP server <-----> Internet
928 ----> DNS server (10.0.2.3)
930 ----> SMB server (10.0.2.4)
933 The QEMU VM behaves as if it was behind a firewall which blocks all
934 incoming connections. You can use a DHCP client to automatically
935 configure the network in the QEMU VM. The DHCP server assign addresses
936 to the hosts starting from 10.0.2.15.
938 In order to check that the user mode network is working, you can ping
939 the address 10.0.2.2 and verify that you got an address in the range
940 10.0.2.x from the QEMU virtual DHCP server.
942 Note that @code{ping} is not supported reliably to the internet as it
943 would require root priviledges. It means you can only ping the local
946 When using the built-in TFTP server, the router is also the TFTP
949 When using the @option{-redir} option, TCP or UDP connections can be
950 redirected from the host to the guest. It allows for example to
951 redirect X11, telnet or SSH connections.
953 @subsection Connecting VLANs between QEMU instances
955 Using the @option{-net socket} option, it is possible to make VLANs
956 that span several QEMU instances. See @ref{sec_invocation} to have a
959 @node direct_linux_boot
960 @section Direct Linux Boot
962 This section explains how to launch a Linux kernel inside QEMU without
963 having to make a full bootable image. It is very useful for fast Linux
964 kernel testing. The QEMU network configuration is also explained.
968 Download the archive @file{linux-test-xxx.tar.gz} containing a Linux
969 kernel and a disk image.
971 @item Optional: If you want network support (for example to launch X11 examples), you
972 must copy the script @file{qemu-ifup} in @file{/etc} and configure
973 properly @code{sudo} so that the command @code{ifconfig} contained in
974 @file{qemu-ifup} can be executed as root. You must verify that your host
975 kernel supports the TUN/TAP network interfaces: the device
976 @file{/dev/net/tun} must be present.
978 When network is enabled, there is a virtual network connection between
979 the host kernel and the emulated kernel. The emulated kernel is seen
980 from the host kernel at IP address 172.20.0.2 and the host kernel is
981 seen from the emulated kernel at IP address 172.20.0.1.
983 @item Launch @code{qemu.sh}. You should have the following output:
987 Connected to host network interface: tun0
988 Linux version 2.4.21 (bellard@@voyager.localdomain) (gcc version 3.2.2 20030222 @/(Red Hat @/Linux 3.2.2-5)) #5 Tue Nov 11 18:18:53 CET 2003
989 BIOS-provided physical RAM map:
990 BIOS-e801: 0000000000000000 - 000000000009f000 (usable)
991 BIOS-e801: 0000000000100000 - 0000000002000000 (usable)
992 32MB LOWMEM available.
993 On node 0 totalpages: 8192
997 Kernel command line: root=/dev/hda sb=0x220,5,1,5 ide2=noprobe ide3=noprobe ide4=noprobe @/ide5=noprobe console=ttyS0
998 ide_setup: ide2=noprobe
999 ide_setup: ide3=noprobe
1000 ide_setup: ide4=noprobe
1001 ide_setup: ide5=noprobe
1003 Detected 2399.621 MHz processor.
1004 Console: colour EGA 80x25
1005 Calibrating delay loop... 4744.80 BogoMIPS
1006 Memory: 28872k/32768k available (1210k kernel code, 3508k reserved, 266k data, 64k init, @/0k highmem)
1007 Dentry cache hash table entries: 4096 (order: 3, 32768 bytes)
1008 Inode cache hash table entries: 2048 (order: 2, 16384 bytes)
1009 Mount cache hash table entries: 512 (order: 0, 4096 bytes)
1010 Buffer-cache hash table entries: 1024 (order: 0, 4096 bytes)
1011 Page-cache hash table entries: 8192 (order: 3, 32768 bytes)
1012 CPU: Intel Pentium Pro stepping 03
1013 Checking 'hlt' instruction... OK.
1014 POSIX conformance testing by UNIFIX
1015 Linux NET4.0 for Linux 2.4
1016 Based upon Swansea University Computer Society NET3.039
1017 Initializing RT netlink socket
1018 apm: BIOS not found.
1020 Journalled Block Device driver loaded
1021 Detected PS/2 Mouse Port.
1022 pty: 256 Unix98 ptys configured
1023 Serial driver version 5.05c (2001-07-08) with no serial options enabled
1024 ttyS00 at 0x03f8 (irq = 4) is a 16450
1025 ne.c:v1.10 9/23/94 Donald Becker (becker@@scyld.com)
1026 Last modified Nov 1, 2000 by Paul Gortmaker
1027 NE*000 ethercard probe at 0x300: 52 54 00 12 34 56
1028 eth0: NE2000 found at 0x300, using IRQ 9.
1029 RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
1030 Uniform Multi-Platform E-IDE driver Revision: 7.00beta4-2.4
1031 ide: Assuming 50MHz system bus speed for PIO modes; override with idebus=xx
1032 hda: QEMU HARDDISK, ATA DISK drive
1033 ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
1034 hda: attached ide-disk driver.
1035 hda: 20480 sectors (10 MB) w/256KiB Cache, CHS=20/16/63
1038 Soundblaster audio driver Copyright (C) by Hannu Savolainen 1993-1996
1039 NET4: Linux TCP/IP 1.0 for NET4.0
1040 IP Protocols: ICMP, UDP, TCP, IGMP
1041 IP: routing cache hash table of 512 buckets, 4Kbytes
1042 TCP: Hash tables configured (established 2048 bind 4096)
1043 NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
1044 EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended
1045 VFS: Mounted root (ext2 filesystem).
1046 Freeing unused kernel memory: 64k freed
1048 Linux version 2.4.21 (bellard@@voyager.localdomain) (gcc version 3.2.2 20030222 @/(Red Hat @/Linux 3.2.2-5)) #5 Tue Nov 11 18:18:53 CET 2003
1050 QEMU Linux test distribution (based on Redhat 9)
1052 Type 'exit' to halt the system
1058 Then you can play with the kernel inside the virtual serial console. You
1059 can launch @code{ls} for example. Type @key{Ctrl-a h} to have an help
1060 about the keys you can type inside the virtual serial console. In
1061 particular, use @key{Ctrl-a x} to exit QEMU and use @key{Ctrl-a b} as
1062 the Magic SysRq key.
1065 If the network is enabled, launch the script @file{/etc/linuxrc} in the
1066 emulator (don't forget the leading dot):
1071 Then enable X11 connections on your PC from the emulated Linux:
1076 You can now launch @file{xterm} or @file{xlogo} and verify that you have
1077 a real Virtual Linux system !
1084 A 2.5.74 kernel is also included in the archive. Just
1085 replace the bzImage in qemu.sh to try it.
1088 In order to exit cleanly from qemu, you can do a @emph{shutdown} inside
1089 qemu. qemu will automatically exit when the Linux shutdown is done.
1092 You can boot slightly faster by disabling the probe of non present IDE
1093 interfaces. To do so, add the following options on the kernel command
1096 ide1=noprobe ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe
1100 The example disk image is a modified version of the one made by Kevin
1101 Lawton for the plex86 Project (@url{www.plex86.org}).
1106 @section USB emulation
1108 QEMU emulates a PCI UHCI USB controller and a 8 port USB hub connected
1109 to it. You can virtually plug to the hub virtual USB devices or real
1110 host USB devices (experimental, works only on Linux hosts).
1112 @subsection Using virtual USB devices
1114 A virtual USB mouse device is available for testing in QEMU.
1116 You can try it with the following monitor commands:
1119 # add the mouse device
1120 (qemu) usb_add mouse
1122 # show the virtual USB devices plugged on the QEMU Virtual USB hub
1124 Device 0.3, speed 12 Mb/s
1126 # after some time you can try to remove the mouse
1130 The option @option{-usbdevice} is similar to the monitor command
1133 @subsection Using host USB devices on a Linux host
1135 WARNING: this is an experimental feature. QEMU will slow down when
1136 using it. USB devices requiring real time streaming (i.e. USB Video
1137 Cameras) are not supported yet.
1140 @item If you use an early Linux 2.4 kernel, verify that no Linux driver
1141 is actually using the USB device. A simple way to do that is simply to
1142 disable the corresponding kernel module by renaming it from @file{mydriver.o}
1143 to @file{mydriver.o.disabled}.
1145 @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
1151 @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:
1153 chown -R myuid /proc/bus/usb
1156 @item Launch QEMU and do in the monitor:
1159 Device 1.2, speed 480 Mb/s
1160 Class 00: USB device 1234:5678, USB DISK
1162 You should see the list of the devices you can use (Never try to use
1163 hubs, it won't work).
1165 @item Add the device in QEMU by using:
1167 usb_add host:1234:5678
1170 Normally the guest OS should report that a new USB device is
1171 plugged. You can use the option @option{-usbdevice} to do the same.
1173 @item Now you can try to use the host USB device in QEMU.
1177 When relaunching QEMU, you may have to unplug and plug again the USB
1178 device to make it work again (this is a bug).
1183 QEMU has a primitive support to work with gdb, so that you can do
1184 'Ctrl-C' while the virtual machine is running and inspect its state.
1186 In order to use gdb, launch qemu with the '-s' option. It will wait for a
1189 > qemu -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1190 -append "root=/dev/hda"
1191 Connected to host network interface: tun0
1192 Waiting gdb connection on port 1234
1195 Then launch gdb on the 'vmlinux' executable:
1200 In gdb, connect to QEMU:
1202 (gdb) target remote localhost:1234
1205 Then you can use gdb normally. For example, type 'c' to launch the kernel:
1210 Here are some useful tips in order to use gdb on system code:
1214 Use @code{info reg} to display all the CPU registers.
1216 Use @code{x/10i $eip} to display the code at the PC position.
1218 Use @code{set architecture i8086} to dump 16 bit code. Then use
1219 @code{x/10i $cs*16+$eip} to dump the code at the PC position.
1222 @node pcsys_os_specific
1223 @section Target OS specific information
1227 To have access to SVGA graphic modes under X11, use the @code{vesa} or
1228 the @code{cirrus} X11 driver. For optimal performances, use 16 bit
1229 color depth in the guest and the host OS.
1231 When using a 2.6 guest Linux kernel, you should add the option
1232 @code{clock=pit} on the kernel command line because the 2.6 Linux
1233 kernels make very strict real time clock checks by default that QEMU
1234 cannot simulate exactly.
1236 When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
1237 not activated because QEMU is slower with this patch. The QEMU
1238 Accelerator Module is also much slower in this case. Earlier Fedora
1239 Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporte this
1240 patch by default. Newer kernels don't have it.
1244 If you have a slow host, using Windows 95 is better as it gives the
1245 best speed. Windows 2000 is also a good choice.
1247 @subsubsection SVGA graphic modes support
1249 QEMU emulates a Cirrus Logic GD5446 Video
1250 card. All Windows versions starting from Windows 95 should recognize
1251 and use this graphic card. For optimal performances, use 16 bit color
1252 depth in the guest and the host OS.
1254 @subsubsection CPU usage reduction
1256 Windows 9x does not correctly use the CPU HLT
1257 instruction. The result is that it takes host CPU cycles even when
1258 idle. You can install the utility from
1259 @url{http://www.user.cityline.ru/~maxamn/amnhltm.zip} to solve this
1260 problem. Note that no such tool is needed for NT, 2000 or XP.
1262 @subsubsection Windows 2000 disk full problem
1264 Windows 2000 has a bug which gives a disk full problem during its
1265 installation. When installing it, use the @option{-win2k-hack} QEMU
1266 option to enable a specific workaround. After Windows 2000 is
1267 installed, you no longer need this option (this option slows down the
1270 @subsubsection Windows 2000 shutdown
1272 Windows 2000 cannot automatically shutdown in QEMU although Windows 98
1273 can. It comes from the fact that Windows 2000 does not automatically
1274 use the APM driver provided by the BIOS.
1276 In order to correct that, do the following (thanks to Struan
1277 Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
1278 Add/Troubleshoot a device => Add a new device & Next => No, select the
1279 hardware from a list & Next => NT Apm/Legacy Support & Next => Next
1280 (again) a few times. Now the driver is installed and Windows 2000 now
1281 correctly instructs QEMU to shutdown at the appropriate moment.
1283 @subsubsection Share a directory between Unix and Windows
1285 See @ref{sec_invocation} about the help of the option @option{-smb}.
1287 @subsubsection Windows XP security problems
1289 Some releases of Windows XP install correctly but give a security
1292 A problem is preventing Windows from accurately checking the
1293 license for this computer. Error code: 0x800703e6.
1295 The only known workaround is to boot in Safe mode
1296 without networking support.
1298 Future QEMU releases are likely to correct this bug.
1300 @subsection MS-DOS and FreeDOS
1302 @subsubsection CPU usage reduction
1304 DOS does not correctly use the CPU HLT instruction. The result is that
1305 it takes host CPU cycles even when idle. You can install the utility
1306 from @url{http://www.vmware.com/software/dosidle210.zip} to solve this
1309 @node QEMU System emulator for non PC targets
1310 @chapter QEMU System emulator for non PC targets
1312 QEMU is a generic emulator and it emulates many non PC
1313 machines. Most of the options are similar to the PC emulator. The
1314 differences are mentionned in the following sections.
1317 * QEMU PowerPC System emulator::
1318 * Sparc32 System emulator invocation::
1319 * Sparc64 System emulator invocation::
1320 * MIPS System emulator invocation::
1321 * ARM System emulator invocation::
1324 @node QEMU PowerPC System emulator
1325 @section QEMU PowerPC System emulator
1327 Use the executable @file{qemu-system-ppc} to simulate a complete PREP
1328 or PowerMac PowerPC system.
1330 QEMU emulates the following PowerMac peripherals:
1336 PCI VGA compatible card with VESA Bochs Extensions
1338 2 PMAC IDE interfaces with hard disk and CD-ROM support
1344 VIA-CUDA with ADB keyboard and mouse.
1347 QEMU emulates the following PREP peripherals:
1353 PCI VGA compatible card with VESA Bochs Extensions
1355 2 IDE interfaces with hard disk and CD-ROM support
1359 NE2000 network adapters
1363 PREP Non Volatile RAM
1365 PC compatible keyboard and mouse.
1368 QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS available at
1369 @url{http://perso.magic.fr/l_indien/OpenHackWare/index.htm}.
1371 @c man begin OPTIONS
1373 The following options are specific to the PowerPC emulation:
1377 @item -g WxH[xDEPTH]
1379 Set the initial VGA graphic mode. The default is 800x600x15.
1386 More information is available at
1387 @url{http://perso.magic.fr/l_indien/qemu-ppc/}.
1389 @node Sparc32 System emulator invocation
1390 @section Sparc32 System emulator invocation
1392 Use the executable @file{qemu-system-sparc} to simulate a JavaStation
1393 (sun4m architecture). The emulation is somewhat complete.
1395 QEMU emulates the following sun4m peripherals:
1403 Lance (Am7990) Ethernet
1405 Non Volatile RAM M48T08
1407 Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
1408 and power/reset logic
1410 ESP SCSI controller with hard disk and CD-ROM support
1415 The number of peripherals is fixed in the architecture.
1417 QEMU uses the Proll, a PROM replacement available at
1418 @url{http://people.redhat.com/@/zaitcev/linux/}. The required
1419 QEMU-specific patches are included with the sources.
1421 A sample Linux 2.6 series kernel and ram disk image are available on
1422 the QEMU web site. Please note that currently neither Linux 2.4
1423 series, NetBSD, nor OpenBSD kernels work.
1425 @c man begin OPTIONS
1427 The following options are specific to the Sparc emulation:
1433 Set the initial TCX graphic mode. The default is 1024x768.
1439 @node Sparc64 System emulator invocation
1440 @section Sparc64 System emulator invocation
1442 Use the executable @file{qemu-system-sparc64} to simulate a Sun4u machine.
1443 The emulator is not usable for anything yet.
1445 QEMU emulates the following sun4u peripherals:
1449 UltraSparc IIi APB PCI Bridge
1451 PCI VGA compatible card with VESA Bochs Extensions
1453 Non Volatile RAM M48T59
1455 PC-compatible serial ports
1458 @node MIPS System emulator invocation
1459 @section MIPS System emulator invocation
1461 Use the executable @file{qemu-system-mips} to simulate a MIPS machine.
1462 The emulator is able to boot a Linux kernel and to run a Linux Debian
1463 installation from NFS. The following devices are emulated:
1469 PC style serial port
1474 More information is available in the QEMU mailing-list archive.
1476 @node ARM System emulator invocation
1477 @section ARM System emulator invocation
1479 Use the executable @file{qemu-system-arm} to simulate a ARM
1480 machine. The ARM Integrator/CP board is emulated with the following
1485 ARM926E or ARM1026E CPU
1489 SMC 91c111 Ethernet adapter
1491 PL110 LCD controller
1493 PL050 KMI with PS/2 keyboard and mouse.
1496 The ARM Versatile baseboard is emulated with the following devices:
1502 PL190 Vectored Interrupt Controller
1506 SMC 91c111 Ethernet adapter
1508 PL110 LCD controller
1510 PL050 KMI with PS/2 keyboard and mouse.
1512 PCI host bridge. Note the emulated PCI bridge only provides access to
1513 PCI memory space. It does not provide access to PCI IO space.
1514 This means some devices (eg. ne2k_pci NIC) are not useable, and others
1515 (eg. rtl8139 NIC) are only useable when the guest drivers use the memory
1516 mapped control registers.
1519 A Linux 2.6 test image is available on the QEMU web site. More
1520 information is available in the QEMU mailing-list archive.
1522 @node QEMU Linux User space emulator
1523 @chapter QEMU Linux User space emulator
1528 * Command line options::
1532 @section Quick Start
1534 In order to launch a Linux process, QEMU needs the process executable
1535 itself and all the target (x86) dynamic libraries used by it.
1539 @item On x86, you can just try to launch any process by using the native
1543 qemu-i386 -L / /bin/ls
1546 @code{-L /} tells that the x86 dynamic linker must be searched with a
1549 @item Since QEMU is also a linux process, you can launch qemu with qemu (NOTE: you can only do that if you compiled QEMU from the sources):
1552 qemu-i386 -L / qemu-i386 -L / /bin/ls
1555 @item On non x86 CPUs, you need first to download at least an x86 glibc
1556 (@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
1557 @code{LD_LIBRARY_PATH} is not set:
1560 unset LD_LIBRARY_PATH
1563 Then you can launch the precompiled @file{ls} x86 executable:
1566 qemu-i386 tests/i386/ls
1568 You can look at @file{qemu-binfmt-conf.sh} so that
1569 QEMU is automatically launched by the Linux kernel when you try to
1570 launch x86 executables. It requires the @code{binfmt_misc} module in the
1573 @item The x86 version of QEMU is also included. You can try weird things such as:
1575 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 \
1576 /usr/local/qemu-i386/bin/ls-i386
1582 @section Wine launch
1586 @item Ensure that you have a working QEMU with the x86 glibc
1587 distribution (see previous section). In order to verify it, you must be
1591 qemu-i386 /usr/local/qemu-i386/bin/ls-i386
1594 @item Download the binary x86 Wine install
1595 (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
1597 @item Configure Wine on your account. Look at the provided script
1598 @file{/usr/local/qemu-i386/@/bin/wine-conf.sh}. Your previous
1599 @code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
1601 @item Then you can try the example @file{putty.exe}:
1604 qemu-i386 /usr/local/qemu-i386/wine/bin/wine \
1605 /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
1610 @node Command line options
1611 @section Command line options
1614 usage: qemu-i386 [-h] [-d] [-L path] [-s size] program [arguments...]
1621 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
1623 Set the x86 stack size in bytes (default=524288)
1630 Activate log (logfile=/tmp/qemu.log)
1632 Act as if the host page size was 'pagesize' bytes
1636 @chapter Compilation from the sources
1641 * Cross compilation for Windows with Linux::
1648 @subsection Compilation
1650 First you must decompress the sources:
1653 tar zxvf qemu-x.y.z.tar.gz
1657 Then you configure QEMU and build it (usually no options are needed):
1663 Then type as root user:
1667 to install QEMU in @file{/usr/local}.
1669 @subsection Tested tool versions
1671 In order to compile QEMU succesfully, it is very important that you
1672 have the right tools. The most important one is gcc. I cannot guaranty
1673 that QEMU works if you do not use a tested gcc version. Look at
1674 'configure' and 'Makefile' if you want to make a different gcc
1678 host gcc binutils glibc linux distribution
1679 ----------------------------------------------------------------------
1680 x86 3.2 2.13.2 2.1.3 2.4.18
1681 2.96 2.11.93.0.2 2.2.5 2.4.18 Red Hat 7.3
1682 3.2.2 2.13.90.0.18 2.3.2 2.4.20 Red Hat 9
1684 PowerPC 3.3 [4] 2.13.90.0.18 2.3.1 2.4.20briq
1687 Alpha 3.3 [1] 2.14.90.0.4 2.2.5 2.2.20 [2] Debian 3.0
1689 Sparc32 2.95.4 2.12.90.0.1 2.2.5 2.4.18 Debian 3.0
1691 ARM 2.95.4 2.12.90.0.1 2.2.5 2.4.9 [3] Debian 3.0
1693 [1] On Alpha, QEMU needs the gcc 'visibility' attribute only available
1694 for gcc version >= 3.3.
1695 [2] Linux >= 2.4.20 is necessary for precise exception support
1697 [3] 2.4.9-ac10-rmk2-np1-cerf2
1699 [4] gcc 2.95.x generates invalid code when using too many register
1700 variables. You must use gcc 3.x on PowerPC.
1707 @item Install the current versions of MSYS and MinGW from
1708 @url{http://www.mingw.org/}. You can find detailed installation
1709 instructions in the download section and the FAQ.
1712 the MinGW development library of SDL 1.2.x
1713 (@file{SDL-devel-1.2.x-@/mingw32.tar.gz}) from
1714 @url{http://www.libsdl.org}. Unpack it in a temporary place, and
1715 unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
1716 directory. Edit the @file{sdl-config} script so that it gives the
1717 correct SDL directory when invoked.
1719 @item Extract the current version of QEMU.
1721 @item Start the MSYS shell (file @file{msys.bat}).
1723 @item Change to the QEMU directory. Launch @file{./configure} and
1724 @file{make}. If you have problems using SDL, verify that
1725 @file{sdl-config} can be launched from the MSYS command line.
1727 @item You can install QEMU in @file{Program Files/Qemu} by typing
1728 @file{make install}. Don't forget to copy @file{SDL.dll} in
1729 @file{Program Files/Qemu}.
1733 @node Cross compilation for Windows with Linux
1734 @section Cross compilation for Windows with Linux
1738 Install the MinGW cross compilation tools available at
1739 @url{http://www.mingw.org/}.
1742 Install the Win32 version of SDL (@url{http://www.libsdl.org}) by
1743 unpacking @file{i386-mingw32msvc.tar.gz}. Set up the PATH environment
1744 variable so that @file{i386-mingw32msvc-sdl-config} can be launched by
1745 the QEMU configuration script.
1748 Configure QEMU for Windows cross compilation:
1750 ./configure --enable-mingw32
1752 If necessary, you can change the cross-prefix according to the prefix
1753 choosen for the MinGW tools with --cross-prefix. You can also use
1754 --prefix to set the Win32 install path.
1756 @item You can install QEMU in the installation directory by typing
1757 @file{make install}. Don't forget to copy @file{SDL.dll} in the
1758 installation directory.
1762 Note: Currently, Wine does not seem able to launch
1768 The Mac OS X patches are not fully merged in QEMU, so you should look
1769 at the QEMU mailing list archive to have all the necessary