1 \input texinfo @c -*- texinfo -*-
4 @settitle QEMU CPU Emulator User Documentation
7 @center @titlefont{QEMU CPU Emulator User Documentation}
16 QEMU is a FAST! processor emulator using dynamic translation to
17 achieve good emulation speed.
19 QEMU has two operating modes:
24 Full system emulation. In this mode, QEMU emulates a full system (for
25 example a PC), including one or several processors and various
26 peripherals. It can be used to launch different Operating Systems
27 without rebooting the PC or to debug system code.
30 User mode emulation (Linux host only). In this mode, QEMU can launch
31 Linux processes compiled for one CPU on another CPU. It can be used to
32 launch the Wine Windows API emulator (@url{http://www.winehq.org}) or
33 to ease cross-compilation and cross-debugging.
37 QEMU can run without an host kernel driver and yet gives acceptable
40 For system emulation, the following hardware targets are supported:
42 @item PC (x86 or x86_64 processor)
43 @item ISA PC (old style PC without PCI bus)
44 @item PREP (PowerPC processor)
45 @item G3 BW PowerMac (PowerPC processor)
46 @item Mac99 PowerMac (PowerPC processor, in progress)
47 @item Sun4m (32-bit Sparc processor)
48 @item Sun4u (64-bit Sparc processor, in progress)
49 @item Malta board (32-bit MIPS processor)
50 @item ARM Integrator/CP (ARM1026E processor)
53 For user emulation, x86, PowerPC, ARM, MIPS, and Sparc32/64 CPUs are supported.
57 If you want to compile QEMU yourself, see @ref{compilation}.
61 If a precompiled package is available for your distribution - you just
62 have to install it. Otherwise, see @ref{compilation}.
66 Download the experimental binary installer at
67 @url{http://www.freeoszoo.org/download.php}.
71 Download the experimental binary installer at
72 @url{http://www.freeoszoo.org/download.php}.
74 @chapter QEMU PC System emulator
78 @c man begin DESCRIPTION
80 The QEMU PC System emulator simulates the
81 following peripherals:
85 i440FX host PCI bridge and PIIX3 PCI to ISA bridge
87 Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
88 extensions (hardware level, including all non standard modes).
90 PS/2 mouse and keyboard
92 2 PCI IDE interfaces with hard disk and CD-ROM support
96 NE2000 PCI network adapters
100 Creative SoundBlaster 16 sound card
102 ENSONIQ AudioPCI ES1370 sound card
104 Adlib(OPL2) - Yamaha YM3812 compatible chip
106 PCI UHCI USB controller and a virtual USB hub.
109 SMP is supported with up to 255 CPUs.
111 Note that adlib is only available when QEMU was configured with
114 QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
117 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
123 Download and uncompress the linux image (@file{linux.img}) and type:
129 Linux should boot and give you a prompt.
135 @c man begin SYNOPSIS
136 usage: qemu [options] [disk_image]
141 @var{disk_image} is a raw hard disk image for IDE hard disk 0.
146 Select the emulated machine (@code{-M ?} for list)
150 Use @var{file} as floppy disk 0/1 image (@xref{disk_images}). You can
151 use the host floppy by using @file{/dev/fd0} as filename.
157 Use @var{file} as hard disk 0, 1, 2 or 3 image (@xref{disk_images}).
160 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and and
161 @option{-cdrom} at the same time). You can use the host CD-ROM by
162 using @file{/dev/cdrom} as filename.
165 Boot on floppy (a), hard disk (c) or CD-ROM (d). Hard disk boot is
169 Write to temporary files instead of disk image files. In this case,
170 the raw disk image you use is not written back. You can however force
171 the write back by pressing @key{C-a s} (@xref{disk_images}).
174 Set virtual RAM size to @var{megs} megabytes. Default is 128 MB.
177 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
182 Normally, QEMU uses SDL to display the VGA output. With this option,
183 you can totally disable graphical output so that QEMU is a simple
184 command line application. The emulated serial port is redirected on
185 the console. Therefore, you can still use QEMU to debug a Linux kernel
186 with a serial console.
190 Use keyboard layout @var{language} (for example @code{fr} for
191 French). This option is only needed where it is not easy to get raw PC
192 keycodes (e.g. on Macs or with some X11 servers). You don't need to
193 use it on PC/Linux or PC/Windows hosts.
195 The available layouts are:
197 ar de-ch es fo fr-ca hu ja mk no pt-br sv
198 da en-gb et fr fr-ch is lt nl pl ru th
199 de en-us fi fr-be hr it lv nl-be pt sl tr
202 The default is @code{en-us}.
206 Will enable audio and all the sound hardware QEMU was built with.
210 Will show the audio subsystem help: list of drivers, tunable
213 @item -soundhw card1,card2,...
215 Enable audio and selected sound hardware. Use ? to print all
216 available sound hardware.
219 qemu -soundhw sb16,adlib hda
220 qemu -soundhw es1370 hda
225 Set the real time clock to local time (the default is to UTC
226 time). This option is needed to have correct date in MS-DOS or
230 Start in full screen.
233 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
237 Use it when installing Windows 2000 to avoid a disk full bug. After
238 Windows 2000 is installed, you no longer need this option (this option
239 slows down the IDE transfers).
247 Enable the USB driver (will be the default soon)
249 @item -usbdevice devname
250 Add the USB device @var{devname}. See the monitor command
251 @code{usb_add} to have more information.
258 @item -net nic[,vlan=n][,macaddr=addr]
259 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
260 = 0 is the default). The NIC is currently an NE2000 on the PC
261 target. Optionally, the MAC address can be changed. If no
262 @option{-net} option is specified, a single NIC is created.
264 @item -net user[,vlan=n]
265 Use the user mode network stack which requires no administrator
266 priviledge to run. This is the default if no @option{-net} option is
269 @item -net tap[,vlan=n][,fd=h][,ifname=name][,script=file]
270 Connect the host TAP network interface @var{name} to VLAN @var{n} and
271 use the network script @var{file} to configure it. The default
272 network script is @file{/etc/qemu-ifup}. If @var{name} is not
273 provided, the OS automatically provides one. @option{fd=h} can be
274 used to specify the handle of an already opened host TAP interface. Example:
277 qemu linux.img -net nic -net tap
280 More complicated example (two NICs, each one connected to a TAP device)
282 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
283 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
287 @item -net socket[,vlan=n][,fd=h][,listen=[host]:port][,connect=host:port]
289 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
290 machine using a TCP socket connection. If @option{listen} is
291 specified, QEMU waits for incoming connections on @var{port}
292 (@var{host} is optional). @option{connect} is used to connect to
293 another QEMU instance using the @option{listen} option. @option{fd=h}
294 specifies an already opened TCP socket.
298 # launch a first QEMU instance
299 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 -net socket,listen=:1234
300 # connect the VLAN 0 of this instance to the VLAN 0 of the first instance
301 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 -net socket,connect=127.0.0.1:1234
304 @item -net socket[,vlan=n][,fd=h][,mcast=maddr:port]
306 Create a VLAN @var{n} shared with another QEMU virtual
307 machines using a UDP multicast socket, effectively making a bus for
308 every QEMU with same multicast address @var{maddr} and @var{port}.
312 Several QEMU can be running on different hosts and share same bus (assuming
313 correct multicast setup for these hosts).
315 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
316 @url{http://user-mode-linux.sf.net}.
317 @item Use @option{fd=h} to specify an already opened UDP multicast socket.
322 # launch one QEMU instance
323 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 -net socket,mcast=230.0.0.1:1234
324 # launch another QEMU instance on same "bus"
325 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 -net socket,mcast=230.0.0.1:1234
326 # launch yet another QEMU instance on same "bus"
327 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 -net socket,mcast=230.0.0.1:1234
330 Example (User Mode Linux compat.):
332 # launch QEMU instance (note mcast address selected is UML's default)
333 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 -net socket,mcast=239.192.168.1:1102
335 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
339 Indicate that no network devices should be configured. It is used to
340 override the default configuration which is activated if no
341 @option{-net} options are provided.
344 When using the user mode network stack, activate a built-in TFTP
345 server. All filenames beginning with @var{prefix} can be downloaded
346 from the host to the guest using a TFTP client. The TFTP client on the
347 guest must be configured in binary mode (use the command @code{bin} of
348 the Unix TFTP client). The host IP address on the guest is as usual
352 When using the user mode network stack, activate a built-in SMB
353 server so that Windows OSes can access to the host files in @file{dir}
356 In the guest Windows OS, the line:
360 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
361 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
363 Then @file{dir} can be accessed in @file{\\smbserver\qemu}.
365 Note that a SAMBA server must be installed on the host OS in
366 @file{/usr/sbin/smbd}. QEMU was tested succesfully with smbd version
367 2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core 3.
369 @item -redir [tcp|udp]:host-port:[guest-host]:guest-port
371 When using the user mode network stack, redirect incoming TCP or UDP
372 connections to the host port @var{host-port} to the guest
373 @var{guest-host} on guest port @var{guest-port}. If @var{guest-host}
374 is not specified, its value is 10.0.2.15 (default address given by the
375 built-in DHCP server).
377 For example, to redirect host X11 connection from screen 1 to guest
378 screen 0, use the following:
382 qemu -redir tcp:6001::6000 [...]
383 # this host xterm should open in the guest X11 server
387 To redirect telnet connections from host port 5555 to telnet port on
388 the guest, use the following:
392 qemu -redir tcp:5555::23 [...]
393 telnet localhost 5555
396 Then when you use on the host @code{telnet localhost 5555}, you
397 connect to the guest telnet server.
401 Linux boot specific: When using these options, you can use a given
402 Linux kernel without installing it in the disk image. It can be useful
403 for easier testing of various kernels.
407 @item -kernel bzImage
408 Use @var{bzImage} as kernel image.
410 @item -append cmdline
411 Use @var{cmdline} as kernel command line
414 Use @var{file} as initial ram disk.
418 Debug/Expert options:
422 Redirect the virtual serial port to host device @var{dev}. Available
428 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
432 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
433 parameters are set according to the emulated ones.
435 [Linux only, parallel port only] Use host parallel port
436 @var{N}. Currently only SPP parallel port features can be used.
438 Write output to filename. No character can be read.
440 [Unix only] standard input/output
442 [Unix only] name pipe @var{filename}
444 The default device is @code{vc} in graphical mode and @code{stdio} in
447 This option can be used several times to simulate up to 4 serials
451 Redirect the virtual parallel port to host device @var{dev} (same
452 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
453 be used to use hardware devices connected on the corresponding host
456 This option can be used several times to simulate up to 3 parallel
460 Redirect the monitor to host device @var{dev} (same devices as the
462 The default device is @code{vc} in graphical mode and @code{stdio} in
466 Wait gdb connection to port 1234 (@xref{gdb_usage}).
468 Change gdb connection port.
470 Do not start CPU at startup (you must type 'c' in the monitor).
472 Output log in /tmp/qemu.log
473 @item -hdachs c,h,s,[,t]
474 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
475 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
476 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
477 all thoses parameters. This option is useful for old MS-DOS disk
481 Simulate a standard VGA card with Bochs VBE extensions (default is
482 Cirrus Logic GD5446 PCI VGA)
484 Start right away with a saved state (@code{loadvm} in monitor)
493 During the graphical emulation, you can use the following keys:
499 Switch to virtual console 'n'. Standard console mappings are:
502 Target system display
510 Toggle mouse and keyboard grab.
513 In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
514 @key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
516 During emulation, if you are using the @option{-nographic} option, use
517 @key{Ctrl-a h} to get terminal commands:
525 Save disk data back to file (if -snapshot)
527 Send break (magic sysrq in Linux)
529 Switch between console and monitor
538 @settitle QEMU System Emulator
541 The HTML documentation of QEMU for more precise information and Linux
542 user mode emulator invocation.
553 @section QEMU Monitor
555 The QEMU monitor is used to give complex commands to the QEMU
556 emulator. You can use it to:
561 Remove or insert removable medias images
562 (such as CD-ROM or floppies)
565 Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
568 @item Inspect the VM state without an external debugger.
574 The following commands are available:
578 @item help or ? [cmd]
579 Show the help for all commands or just for command @var{cmd}.
582 Commit changes to the disk images (if -snapshot is used)
584 @item info subcommand
585 show various information about the system state
589 show the various VLANs and the associated devices
591 show the block devices
593 show the cpu registers
595 show the command line history
597 show emulated PCI device
599 show USB devices plugged on the virtual USB hub
601 show all USB host devices
607 @item eject [-f] device
608 Eject a removable media (use -f to force it).
610 @item change device filename
611 Change a removable media.
613 @item screendump filename
614 Save screen into PPM image @var{filename}.
616 @item log item1[,...]
617 Activate logging of the specified items to @file{/tmp/qemu.log}.
619 @item savevm filename
620 Save the whole virtual machine state to @var{filename}.
622 @item loadvm filename
623 Restore the whole virtual machine state from @var{filename}.
631 @item gdbserver [port]
632 Start gdbserver session (default port=1234)
635 Virtual memory dump starting at @var{addr}.
638 Physical memory dump starting at @var{addr}.
640 @var{fmt} is a format which tells the command how to format the
641 data. Its syntax is: @option{/@{count@}@{format@}@{size@}}
645 is the number of items to be dumped.
648 can be x (hexa), d (signed decimal), u (unsigned decimal), o (octal),
649 c (char) or i (asm instruction).
652 can be b (8 bits), h (16 bits), w (32 bits) or g (64 bits). On x86,
653 @code{h} or @code{w} can be specified with the @code{i} format to
654 respectively select 16 or 32 bit code instruction size.
661 Dump 10 instructions at the current instruction pointer:
666 0x90107065: lea 0x0(%esi,1),%esi
667 0x90107069: lea 0x0(%edi,1),%edi
669 0x90107071: jmp 0x90107080
677 Dump 80 16 bit values at the start of the video memory.
679 (qemu) xp/80hx 0xb8000
680 0x000b8000: 0x0b50 0x0b6c 0x0b65 0x0b78 0x0b38 0x0b36 0x0b2f 0x0b42
681 0x000b8010: 0x0b6f 0x0b63 0x0b68 0x0b73 0x0b20 0x0b56 0x0b47 0x0b41
682 0x000b8020: 0x0b42 0x0b69 0x0b6f 0x0b73 0x0b20 0x0b63 0x0b75 0x0b72
683 0x000b8030: 0x0b72 0x0b65 0x0b6e 0x0b74 0x0b2d 0x0b63 0x0b76 0x0b73
684 0x000b8040: 0x0b20 0x0b30 0x0b35 0x0b20 0x0b4e 0x0b6f 0x0b76 0x0b20
685 0x000b8050: 0x0b32 0x0b30 0x0b30 0x0b33 0x0720 0x0720 0x0720 0x0720
686 0x000b8060: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
687 0x000b8070: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
688 0x000b8080: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
689 0x000b8090: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
693 @item p or print/fmt expr
695 Print expression value. Only the @var{format} part of @var{fmt} is
700 Send @var{keys} to the emulator. Use @code{-} to press several keys
701 simultaneously. Example:
706 This command is useful to send keys that your graphical user interface
707 intercepts at low level, such as @code{ctrl-alt-f1} in X Window.
713 @item usb_add devname
715 Plug the USB device devname to the QEMU virtual USB hub. @var{devname}
716 is either a virtual device name (for example @code{mouse}) or a host
717 USB device identifier. Host USB device identifiers have the following
718 syntax: @code{host:bus.addr} or @code{host:vendor_id:product_id}.
720 @item usb_del devname
722 Remove the USB device @var{devname} from the QEMU virtual USB
723 hub. @var{devname} has the syntax @code{bus.addr}. Use the monitor
724 command @code{info usb} to see the devices you can remove.
728 @subsection Integer expressions
730 The monitor understands integers expressions for every integer
731 argument. You can use register names to get the value of specifics
732 CPU registers by prefixing them with @emph{$}.
737 Since version 0.6.1, QEMU supports many disk image formats, including
738 growable disk images (their size increase as non empty sectors are
739 written), compressed and encrypted disk images.
741 @subsection Quick start for disk image creation
743 You can create a disk image with the command:
745 qemu-img create myimage.img mysize
747 where @var{myimage.img} is the disk image filename and @var{mysize} is its
748 size in kilobytes. You can add an @code{M} suffix to give the size in
749 megabytes and a @code{G} suffix for gigabytes.
751 @xref{qemu_img_invocation} for more information.
753 @subsection Snapshot mode
755 If you use the option @option{-snapshot}, all disk images are
756 considered as read only. When sectors in written, they are written in
757 a temporary file created in @file{/tmp}. You can however force the
758 write back to the raw disk images by using the @code{commit} monitor
759 command (or @key{C-a s} in the serial console).
761 @node qemu_img_invocation
762 @subsection @code{qemu-img} Invocation
764 @include qemu-img.texi
766 @subsection Virtual FAT disk images
768 QEMU can automatically create a virtual FAT disk image from a
769 directory tree. In order to use it, just type:
772 qemu linux.img -hdb fat:/my_directory
775 Then you access access to all the files in the @file{/my_directory}
776 directory without having to copy them in a disk image or to export
777 them via SAMBA or NFS. The default access is @emph{read-only}.
779 Floppies can be emulated with the @code{:floppy:} option:
782 qemu linux.img -fda fat:floppy:/my_directory
785 A read/write support is available for testing (beta stage) with the
789 qemu linux.img -fda fat:floppy:rw:/my_directory
792 What you should @emph{never} do:
794 @item use non-ASCII filenames ;
795 @item use "-snapshot" together with ":rw:" ;
796 @item expect it to work when loadvm'ing.
799 @section Network emulation
801 QEMU can simulate several networks cards (NE2000 boards on the PC
802 target) and can connect them to an arbitrary number of Virtual Local
803 Area Networks (VLANs). Host TAP devices can be connected to any QEMU
804 VLAN. VLAN can be connected between separate instances of QEMU to
805 simulate large networks. For simpler usage, a non priviledged user mode
806 network stack can replace the TAP device to have a basic network
811 QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
812 connection between several network devices. These devices can be for
813 example QEMU virtual Ethernet cards or virtual Host ethernet devices
816 @subsection Using TAP network interfaces
818 This is the standard way to connect QEMU to a real network. QEMU adds
819 a virtual network device on your host (called @code{tapN}), and you
820 can then configure it as if it was a real ethernet card.
822 As an example, you can download the @file{linux-test-xxx.tar.gz}
823 archive and copy the script @file{qemu-ifup} in @file{/etc} and
824 configure properly @code{sudo} so that the command @code{ifconfig}
825 contained in @file{qemu-ifup} can be executed as root. You must verify
826 that your host kernel supports the TAP network interfaces: the
827 device @file{/dev/net/tun} must be present.
829 See @ref{direct_linux_boot} to have an example of network use with a
830 Linux distribution and @ref{sec_invocation} to have examples of
831 command lines using the TAP network interfaces.
833 @subsection Using the user mode network stack
835 By using the option @option{-net user} (default configuration if no
836 @option{-net} option is specified), QEMU uses a completely user mode
837 network stack (you don't need root priviledge to use the virtual
838 network). The virtual network configuration is the following:
842 QEMU VLAN <------> Firewall/DHCP server <-----> Internet
845 ----> DNS server (10.0.2.3)
847 ----> SMB server (10.0.2.4)
850 The QEMU VM behaves as if it was behind a firewall which blocks all
851 incoming connections. You can use a DHCP client to automatically
852 configure the network in the QEMU VM. The DHCP server assign addresses
853 to the hosts starting from 10.0.2.15.
855 In order to check that the user mode network is working, you can ping
856 the address 10.0.2.2 and verify that you got an address in the range
857 10.0.2.x from the QEMU virtual DHCP server.
859 Note that @code{ping} is not supported reliably to the internet as it
860 would require root priviledges. It means you can only ping the local
863 When using the built-in TFTP server, the router is also the TFTP
866 When using the @option{-redir} option, TCP or UDP connections can be
867 redirected from the host to the guest. It allows for example to
868 redirect X11, telnet or SSH connections.
870 @subsection Connecting VLANs between QEMU instances
872 Using the @option{-net socket} option, it is possible to make VLANs
873 that span several QEMU instances. See @ref{sec_invocation} to have a
876 @node direct_linux_boot
877 @section Direct Linux Boot
879 This section explains how to launch a Linux kernel inside QEMU without
880 having to make a full bootable image. It is very useful for fast Linux
881 kernel testing. The QEMU network configuration is also explained.
885 Download the archive @file{linux-test-xxx.tar.gz} containing a Linux
886 kernel and a disk image.
888 @item Optional: If you want network support (for example to launch X11 examples), you
889 must copy the script @file{qemu-ifup} in @file{/etc} and configure
890 properly @code{sudo} so that the command @code{ifconfig} contained in
891 @file{qemu-ifup} can be executed as root. You must verify that your host
892 kernel supports the TUN/TAP network interfaces: the device
893 @file{/dev/net/tun} must be present.
895 When network is enabled, there is a virtual network connection between
896 the host kernel and the emulated kernel. The emulated kernel is seen
897 from the host kernel at IP address 172.20.0.2 and the host kernel is
898 seen from the emulated kernel at IP address 172.20.0.1.
900 @item Launch @code{qemu.sh}. You should have the following output:
904 Connected to host network interface: tun0
905 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
906 BIOS-provided physical RAM map:
907 BIOS-e801: 0000000000000000 - 000000000009f000 (usable)
908 BIOS-e801: 0000000000100000 - 0000000002000000 (usable)
909 32MB LOWMEM available.
910 On node 0 totalpages: 8192
914 Kernel command line: root=/dev/hda sb=0x220,5,1,5 ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe console=ttyS0
915 ide_setup: ide2=noprobe
916 ide_setup: ide3=noprobe
917 ide_setup: ide4=noprobe
918 ide_setup: ide5=noprobe
920 Detected 2399.621 MHz processor.
921 Console: colour EGA 80x25
922 Calibrating delay loop... 4744.80 BogoMIPS
923 Memory: 28872k/32768k available (1210k kernel code, 3508k reserved, 266k data, 64k init, 0k highmem)
924 Dentry cache hash table entries: 4096 (order: 3, 32768 bytes)
925 Inode cache hash table entries: 2048 (order: 2, 16384 bytes)
926 Mount cache hash table entries: 512 (order: 0, 4096 bytes)
927 Buffer-cache hash table entries: 1024 (order: 0, 4096 bytes)
928 Page-cache hash table entries: 8192 (order: 3, 32768 bytes)
929 CPU: Intel Pentium Pro stepping 03
930 Checking 'hlt' instruction... OK.
931 POSIX conformance testing by UNIFIX
932 Linux NET4.0 for Linux 2.4
933 Based upon Swansea University Computer Society NET3.039
934 Initializing RT netlink socket
937 Journalled Block Device driver loaded
938 Detected PS/2 Mouse Port.
939 pty: 256 Unix98 ptys configured
940 Serial driver version 5.05c (2001-07-08) with no serial options enabled
941 ttyS00 at 0x03f8 (irq = 4) is a 16450
942 ne.c:v1.10 9/23/94 Donald Becker (becker@scyld.com)
943 Last modified Nov 1, 2000 by Paul Gortmaker
944 NE*000 ethercard probe at 0x300: 52 54 00 12 34 56
945 eth0: NE2000 found at 0x300, using IRQ 9.
946 RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
947 Uniform Multi-Platform E-IDE driver Revision: 7.00beta4-2.4
948 ide: Assuming 50MHz system bus speed for PIO modes; override with idebus=xx
949 hda: QEMU HARDDISK, ATA DISK drive
950 ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
951 hda: attached ide-disk driver.
952 hda: 20480 sectors (10 MB) w/256KiB Cache, CHS=20/16/63
955 Soundblaster audio driver Copyright (C) by Hannu Savolainen 1993-1996
956 NET4: Linux TCP/IP 1.0 for NET4.0
957 IP Protocols: ICMP, UDP, TCP, IGMP
958 IP: routing cache hash table of 512 buckets, 4Kbytes
959 TCP: Hash tables configured (established 2048 bind 4096)
960 NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
961 EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended
962 VFS: Mounted root (ext2 filesystem).
963 Freeing unused kernel memory: 64k freed
965 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
967 QEMU Linux test distribution (based on Redhat 9)
969 Type 'exit' to halt the system
975 Then you can play with the kernel inside the virtual serial console. You
976 can launch @code{ls} for example. Type @key{Ctrl-a h} to have an help
977 about the keys you can type inside the virtual serial console. In
978 particular, use @key{Ctrl-a x} to exit QEMU and use @key{Ctrl-a b} as
982 If the network is enabled, launch the script @file{/etc/linuxrc} in the
983 emulator (don't forget the leading dot):
988 Then enable X11 connections on your PC from the emulated Linux:
993 You can now launch @file{xterm} or @file{xlogo} and verify that you have
994 a real Virtual Linux system !
1001 A 2.5.74 kernel is also included in the archive. Just
1002 replace the bzImage in qemu.sh to try it.
1005 In order to exit cleanly from qemu, you can do a @emph{shutdown} inside
1006 qemu. qemu will automatically exit when the Linux shutdown is done.
1009 You can boot slightly faster by disabling the probe of non present IDE
1010 interfaces. To do so, add the following options on the kernel command
1013 ide1=noprobe ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe
1017 The example disk image is a modified version of the one made by Kevin
1018 Lawton for the plex86 Project (@url{www.plex86.org}).
1022 @section USB emulation
1024 QEMU emulates a PCI UHCI USB controller and a 8 port USB hub connected
1025 to it. You can virtually plug to the hub virtual USB devices or real
1026 host USB devices (experimental, works only on Linux hosts).
1028 @subsection Using virtual USB devices
1030 A virtual USB mouse device is available for testing in QEMU.
1032 You can try it with the following monitor commands:
1035 # add the mouse device
1036 (qemu) usb_add mouse
1038 # show the virtual USB devices plugged on the QEMU Virtual USB hub
1040 Device 0.3, speed 12 Mb/s
1042 # after some time you can try to remove the mouse
1046 The option @option{-usbdevice} is similar to the monitor command
1049 @subsection Using host USB devices on a Linux host
1051 WARNING: this is an experimental feature. QEMU will slow down when
1052 using it. USB devices requiring real time streaming (i.e. USB Video
1053 Cameras) are not supported yet.
1056 @item If you use an early Linux 2.4 kernel, verify that no Linux driver
1057 is actually using the USB device. A simple way to do that is simply to
1058 disable the corresponding kernel module by renaming it from @file{mydriver.o}
1059 to @file{mydriver.o.disabled}.
1061 @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
1067 @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:
1069 chown -R myuid /proc/bus/usb
1072 @item Launch QEMU and do in the monitor:
1075 Device 1.2, speed 480 Mb/s
1076 Class 00: USB device 1234:5678, USB DISK
1078 You should see the list of the devices you can use (Never try to use
1079 hubs, it won't work).
1081 @item Add the device in QEMU by using:
1083 usb_add host:1234:5678
1086 Normally the guest OS should report that a new USB device is
1087 plugged. You can use the option @option{-usbdevice} to do the same.
1089 @item Now you can try to use the host USB device in QEMU.
1093 When relaunching QEMU, you may have to unplug and plug again the USB
1094 device to make it work again (this is a bug).
1099 QEMU has a primitive support to work with gdb, so that you can do
1100 'Ctrl-C' while the virtual machine is running and inspect its state.
1102 In order to use gdb, launch qemu with the '-s' option. It will wait for a
1105 > qemu -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img -append "root=/dev/hda"
1106 Connected to host network interface: tun0
1107 Waiting gdb connection on port 1234
1110 Then launch gdb on the 'vmlinux' executable:
1115 In gdb, connect to QEMU:
1117 (gdb) target remote localhost:1234
1120 Then you can use gdb normally. For example, type 'c' to launch the kernel:
1125 Here are some useful tips in order to use gdb on system code:
1129 Use @code{info reg} to display all the CPU registers.
1131 Use @code{x/10i $eip} to display the code at the PC position.
1133 Use @code{set architecture i8086} to dump 16 bit code. Then use
1134 @code{x/10i $cs*16+*eip} to dump the code at the PC position.
1137 @section Target OS specific information
1141 To have access to SVGA graphic modes under X11, use the @code{vesa} or
1142 the @code{cirrus} X11 driver. For optimal performances, use 16 bit
1143 color depth in the guest and the host OS.
1145 When using a 2.6 guest Linux kernel, you should add the option
1146 @code{clock=pit} on the kernel command line because the 2.6 Linux
1147 kernels make very strict real time clock checks by default that QEMU
1148 cannot simulate exactly.
1150 When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
1151 not activated because QEMU is slower with this patch. The QEMU
1152 Accelerator Module is also much slower in this case. Earlier Fedora
1153 Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporte this
1154 patch by default. Newer kernels don't have it.
1158 If you have a slow host, using Windows 95 is better as it gives the
1159 best speed. Windows 2000 is also a good choice.
1161 @subsubsection SVGA graphic modes support
1163 QEMU emulates a Cirrus Logic GD5446 Video
1164 card. All Windows versions starting from Windows 95 should recognize
1165 and use this graphic card. For optimal performances, use 16 bit color
1166 depth in the guest and the host OS.
1168 @subsubsection CPU usage reduction
1170 Windows 9x does not correctly use the CPU HLT
1171 instruction. The result is that it takes host CPU cycles even when
1172 idle. You can install the utility from
1173 @url{http://www.user.cityline.ru/~maxamn/amnhltm.zip} to solve this
1174 problem. Note that no such tool is needed for NT, 2000 or XP.
1176 @subsubsection Windows 2000 disk full problem
1178 Windows 2000 has a bug which gives a disk full problem during its
1179 installation. When installing it, use the @option{-win2k-hack} QEMU
1180 option to enable a specific workaround. After Windows 2000 is
1181 installed, you no longer need this option (this option slows down the
1184 @subsubsection Windows 2000 shutdown
1186 Windows 2000 cannot automatically shutdown in QEMU although Windows 98
1187 can. It comes from the fact that Windows 2000 does not automatically
1188 use the APM driver provided by the BIOS.
1190 In order to correct that, do the following (thanks to Struan
1191 Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
1192 Add/Troubleshoot a device => Add a new device & Next => No, select the
1193 hardware from a list & Next => NT Apm/Legacy Support & Next => Next
1194 (again) a few times. Now the driver is installed and Windows 2000 now
1195 correctly instructs QEMU to shutdown at the appropriate moment.
1197 @subsubsection Share a directory between Unix and Windows
1199 See @ref{sec_invocation} about the help of the option @option{-smb}.
1201 @subsubsection Windows XP security problems
1203 Some releases of Windows XP install correctly but give a security
1206 A problem is preventing Windows from accurately checking the
1207 license for this computer. Error code: 0x800703e6.
1209 The only known workaround is to boot in Safe mode
1210 without networking support.
1212 Future QEMU releases are likely to correct this bug.
1214 @subsection MS-DOS and FreeDOS
1216 @subsubsection CPU usage reduction
1218 DOS does not correctly use the CPU HLT instruction. The result is that
1219 it takes host CPU cycles even when idle. You can install the utility
1220 from @url{http://www.vmware.com/software/dosidle210.zip} to solve this
1223 @chapter QEMU System emulator for non PC targets
1225 QEMU is a generic emulator and it emulates many non PC
1226 machines. Most of the options are similar to the PC emulator. The
1227 differences are mentionned in the following sections.
1229 @section QEMU PowerPC System emulator
1231 Use the executable @file{qemu-system-ppc} to simulate a complete PREP
1232 or PowerMac PowerPC system.
1234 QEMU emulates the following PowerMac peripherals:
1240 PCI VGA compatible card with VESA Bochs Extensions
1242 2 PMAC IDE interfaces with hard disk and CD-ROM support
1248 VIA-CUDA with ADB keyboard and mouse.
1251 QEMU emulates the following PREP peripherals:
1257 PCI VGA compatible card with VESA Bochs Extensions
1259 2 IDE interfaces with hard disk and CD-ROM support
1263 NE2000 network adapters
1267 PREP Non Volatile RAM
1269 PC compatible keyboard and mouse.
1272 QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS available at
1273 @url{http://perso.magic.fr/l_indien/OpenHackWare/index.htm}.
1275 @c man begin OPTIONS
1277 The following options are specific to the PowerPC emulation:
1281 @item -g WxH[xDEPTH]
1283 Set the initial VGA graphic mode. The default is 800x600x15.
1290 More information is available at
1291 @url{http://perso.magic.fr/l_indien/qemu-ppc/}.
1293 @section Sparc32 System emulator invocation
1295 Use the executable @file{qemu-system-sparc} to simulate a JavaStation
1296 (sun4m architecture). The emulation is somewhat complete.
1298 QEMU emulates the following sun4m peripherals:
1306 Lance (Am7990) Ethernet
1308 Non Volatile RAM M48T08
1310 Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
1311 and power/reset logic
1313 ESP SCSI controller with hard disk and CD-ROM support
1318 The number of peripherals is fixed in the architecture.
1320 QEMU uses the Proll, a PROM replacement available at
1321 @url{http://people.redhat.com/zaitcev/linux/}. The required
1322 QEMU-specific patches are included with the sources.
1324 A sample Linux 2.6 series kernel and ram disk image are available on
1325 the QEMU web site. Please note that currently neither Linux 2.4
1326 series, NetBSD, nor OpenBSD kernels work.
1328 @c man begin OPTIONS
1330 The following options are specific to the Sparc emulation:
1336 Set the initial TCX graphic mode. The default is 1024x768.
1342 @section Sparc64 System emulator invocation
1344 Use the executable @file{qemu-system-sparc64} to simulate a Sun4u machine.
1345 The emulator is not usable for anything yet.
1347 QEMU emulates the following sun4u peripherals:
1351 UltraSparc IIi APB PCI Bridge
1353 PCI VGA compatible card with VESA Bochs Extensions
1355 Non Volatile RAM M48T59
1357 PC-compatible serial ports
1360 @section MIPS System emulator invocation
1362 Use the executable @file{qemu-system-mips} to simulate a MIPS machine.
1363 The emulator is able to boot a Linux kernel and to run a Linux Debian
1364 installation from NFS. The following devices are emulated:
1370 PC style serial port
1375 More information is available in the QEMU mailing-list archive.
1377 @section ARM System emulator invocation
1379 Use the executable @file{qemu-system-arm} to simulate a ARM
1380 machine. The ARM Integrator/CP board is emulated with the following
1389 SMC 91c111 Ethernet adapter
1392 A Linux 2.6 test image is available on the QEMU web site. More
1393 information is available in the QEMU mailing-list archive.
1395 @chapter QEMU Linux User space emulator
1397 @section Quick Start
1399 In order to launch a Linux process, QEMU needs the process executable
1400 itself and all the target (x86) dynamic libraries used by it.
1404 @item On x86, you can just try to launch any process by using the native
1408 qemu-i386 -L / /bin/ls
1411 @code{-L /} tells that the x86 dynamic linker must be searched with a
1414 @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):
1417 qemu-i386 -L / qemu-i386 -L / /bin/ls
1420 @item On non x86 CPUs, you need first to download at least an x86 glibc
1421 (@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
1422 @code{LD_LIBRARY_PATH} is not set:
1425 unset LD_LIBRARY_PATH
1428 Then you can launch the precompiled @file{ls} x86 executable:
1431 qemu-i386 tests/i386/ls
1433 You can look at @file{qemu-binfmt-conf.sh} so that
1434 QEMU is automatically launched by the Linux kernel when you try to
1435 launch x86 executables. It requires the @code{binfmt_misc} module in the
1438 @item The x86 version of QEMU is also included. You can try weird things such as:
1440 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 /usr/local/qemu-i386/bin/ls-i386
1445 @section Wine launch
1449 @item Ensure that you have a working QEMU with the x86 glibc
1450 distribution (see previous section). In order to verify it, you must be
1454 qemu-i386 /usr/local/qemu-i386/bin/ls-i386
1457 @item Download the binary x86 Wine install
1458 (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
1460 @item Configure Wine on your account. Look at the provided script
1461 @file{/usr/local/qemu-i386/bin/wine-conf.sh}. Your previous
1462 @code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
1464 @item Then you can try the example @file{putty.exe}:
1467 qemu-i386 /usr/local/qemu-i386/wine/bin/wine /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
1472 @section Command line options
1475 usage: qemu-i386 [-h] [-d] [-L path] [-s size] program [arguments...]
1482 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
1484 Set the x86 stack size in bytes (default=524288)
1491 Activate log (logfile=/tmp/qemu.log)
1493 Act as if the host page size was 'pagesize' bytes
1497 @chapter Compilation from the sources
1501 @subsection Compilation
1503 First you must decompress the sources:
1506 tar zxvf qemu-x.y.z.tar.gz
1510 Then you configure QEMU and build it (usually no options are needed):
1516 Then type as root user:
1520 to install QEMU in @file{/usr/local}.
1522 @subsection Tested tool versions
1524 In order to compile QEMU succesfully, it is very important that you
1525 have the right tools. The most important one is gcc. I cannot guaranty
1526 that QEMU works if you do not use a tested gcc version. Look at
1527 'configure' and 'Makefile' if you want to make a different gcc
1531 host gcc binutils glibc linux distribution
1532 ----------------------------------------------------------------------
1533 x86 3.2 2.13.2 2.1.3 2.4.18
1534 2.96 2.11.93.0.2 2.2.5 2.4.18 Red Hat 7.3
1535 3.2.2 2.13.90.0.18 2.3.2 2.4.20 Red Hat 9
1537 PowerPC 3.3 [4] 2.13.90.0.18 2.3.1 2.4.20briq
1540 Alpha 3.3 [1] 2.14.90.0.4 2.2.5 2.2.20 [2] Debian 3.0
1542 Sparc32 2.95.4 2.12.90.0.1 2.2.5 2.4.18 Debian 3.0
1544 ARM 2.95.4 2.12.90.0.1 2.2.5 2.4.9 [3] Debian 3.0
1546 [1] On Alpha, QEMU needs the gcc 'visibility' attribute only available
1547 for gcc version >= 3.3.
1548 [2] Linux >= 2.4.20 is necessary for precise exception support
1550 [3] 2.4.9-ac10-rmk2-np1-cerf2
1552 [4] gcc 2.95.x generates invalid code when using too many register
1553 variables. You must use gcc 3.x on PowerPC.
1559 @item Install the current versions of MSYS and MinGW from
1560 @url{http://www.mingw.org/}. You can find detailed installation
1561 instructions in the download section and the FAQ.
1564 the MinGW development library of SDL 1.2.x
1565 (@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
1566 @url{http://www.libsdl.org}. Unpack it in a temporary place, and
1567 unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
1568 directory. Edit the @file{sdl-config} script so that it gives the
1569 correct SDL directory when invoked.
1571 @item Extract the current version of QEMU.
1573 @item Start the MSYS shell (file @file{msys.bat}).
1575 @item Change to the QEMU directory. Launch @file{./configure} and
1576 @file{make}. If you have problems using SDL, verify that
1577 @file{sdl-config} can be launched from the MSYS command line.
1579 @item You can install QEMU in @file{Program Files/Qemu} by typing
1580 @file{make install}. Don't forget to copy @file{SDL.dll} in
1581 @file{Program Files/Qemu}.
1585 @section Cross compilation for Windows with Linux
1589 Install the MinGW cross compilation tools available at
1590 @url{http://www.mingw.org/}.
1593 Install the Win32 version of SDL (@url{http://www.libsdl.org}) by
1594 unpacking @file{i386-mingw32msvc.tar.gz}. Set up the PATH environment
1595 variable so that @file{i386-mingw32msvc-sdl-config} can be launched by
1596 the QEMU configuration script.
1599 Configure QEMU for Windows cross compilation:
1601 ./configure --enable-mingw32
1603 If necessary, you can change the cross-prefix according to the prefix
1604 choosen for the MinGW tools with --cross-prefix. You can also use
1605 --prefix to set the Win32 install path.
1607 @item You can install QEMU in the installation directory by typing
1608 @file{make install}. Don't forget to copy @file{SDL.dll} in the
1609 installation directory.
1613 Note: Currently, Wine does not seem able to launch
1618 The Mac OS X patches are not fully merged in QEMU, so you should look
1619 at the QEMU mailing list archive to have all the necessary