\input texinfo @c -*- texinfo -*-
@iftex
-@settitle QEMU CPU Emulator Reference Documentation
+@settitle QEMU CPU Emulator User Documentation
@titlepage
@sp 7
-@center @titlefont{QEMU CPU Emulator Reference Documentation}
+@center @titlefont{QEMU CPU Emulator User Documentation}
@sp 3
@end titlepage
@end iftex
@section Features
-QEMU is a FAST! processor emulator. By using dynamic translation it
-achieves a reasonnable speed while being easy to port on new host
-CPUs.
+QEMU is a FAST! processor emulator using dynamic translation to
+achieve good emulation speed.
QEMU has two operating modes:
@itemize @minus
@item
-User mode emulation. In this mode, QEMU can launch Linux processes
-compiled for one CPU on another CPU. Linux system calls are converted
-because of endianness and 32/64 bit mismatches. The Wine Windows API
-emulator (@url{http://www.winehq.org}) and the DOSEMU DOS emulator
-(@url{www.dosemu.org}) are the main targets for QEMU.
+Full system emulation. In this mode, QEMU emulates a full system (for
+example a PC), including a processor and various peripherals. It can
+be used to launch different Operating Systems without rebooting the
+PC or to debug system code.
@item
-Full system emulation. In this mode, QEMU emulates a full
-system, including a processor and various peripherials. Currently, it
-is only used to launch an x86 Linux kernel on an x86 Linux system. It
-enables easier testing and debugging of system code. It can also be
-used to provide virtual hosting of several virtual PCs on a single
-server.
+User mode emulation (Linux host only). In this mode, QEMU can launch
+Linux processes compiled for one CPU on another CPU. It can be used to
+launch the Wine Windows API emulator (@url{http://www.winehq.org}) or
+to ease cross-compilation and cross-debugging.
@end itemize
-As QEMU requires no host kernel patches to run, it is very safe and
-easy to use.
+QEMU can run without an host kernel driver and yet gives acceptable
+performance.
-QEMU generic features:
+For system emulation, the following hardware targets are supported:
+@itemize
+@item PC (x86 or x86_64 processor)
+@item PREP (PowerPC processor)
+@item G3 BW PowerMac (PowerPC processor)
+@item Mac99 PowerMac (PowerPC processor, in progress)
+@item Sun4m (32-bit Sparc processor)
+@item Sun4u (64-bit Sparc processor, in progress)
+@item Malta board (32-bit MIPS processor, in progress)
+@end itemize
-@itemize
+For user emulation, x86, PowerPC, ARM, and Sparc32/64 CPUs are supported.
-@item User space only or full system emulation.
+@chapter Installation
-@item Using dynamic translation to native code for reasonnable speed.
+If you want to compile QEMU yourself, see @ref{compilation}.
-@item Working on x86 and PowerPC hosts. Being tested on ARM, Sparc32, Alpha and S390.
+@section Linux
-@item Self-modifying code support.
+If a precompiled package is available for your distribution - you just
+have to install it. Otherwise, see @ref{compilation}.
-@item Precise exceptions support.
+@section Windows
-@item The virtual CPU is a library (@code{libqemu}) which can be used
-in other projects.
+Download the experimental binary installer at
+@url{http://www.freeoszoo.org/download.php}.
-@end itemize
+@section Mac OS X
-QEMU user mode emulation features:
-@itemize
-@item Generic Linux system call converter, including most ioctls.
+Download the experimental binary installer at
+@url{http://www.freeoszoo.org/download.php}.
-@item clone() emulation using native CPU clone() to use Linux scheduler for threads.
+@chapter QEMU PC System emulator invocation
-@item Accurate signal handling by remapping host signals to target signals.
-@end itemize
-@end itemize
+@section Introduction
+
+@c man begin DESCRIPTION
+
+The QEMU System emulator simulates the
+following PC peripherals:
-QEMU full system emulation features:
-@itemize
-@item QEMU can either use a full software MMU for maximum portability or use the host system call mmap() to simulate the target MMU.
+@itemize @minus
+@item
+i440FX host PCI bridge and PIIX3 PCI to ISA bridge
+@item
+Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
+extensions (hardware level, including all non standard modes).
+@item
+PS/2 mouse and keyboard
+@item
+2 PCI IDE interfaces with hard disk and CD-ROM support
+@item
+Floppy disk
+@item
+NE2000 PCI network adapters
+@item
+Serial ports
+@item
+Creative SoundBlaster 16 sound card
+@item
+ENSONIQ AudioPCI ES1370 sound card
+@item
+Adlib(OPL2) - Yamaha YM3812 compatible chip
+@item
+PCI UHCI USB controller and a virtual USB hub.
@end itemize
-@section x86 emulation
+Note that adlib is only available when QEMU was configured with
+-enable-adlib
-QEMU x86 target features:
+QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
+VGA BIOS.
-@itemize
+QEMU uses YM3812 emulation by Tatsuyuki Satoh.
-@item The virtual x86 CPU supports 16 bit and 32 bit addressing with segmentation.
-LDT/GDT and IDT are emulated. VM86 mode is also supported to run DOSEMU.
+@c man end
-@item Support of host page sizes bigger than 4KB in user mode emulation.
+@section Quick Start
-@item QEMU can emulate itself on x86.
+Download and uncompress the linux image (@file{linux.img}) and type:
-@item An extensive Linux x86 CPU test program is included @file{tests/test-i386}.
-It can be used to test other x86 virtual CPUs.
+@example
+qemu linux.img
+@end example
-@end itemize
+Linux should boot and give you a prompt.
-Current QEMU limitations:
+@node sec_invocation
+@section Invocation
-@itemize
+@example
+@c man begin SYNOPSIS
+usage: qemu [options] [disk_image]
+@c man end
+@end example
-@item No SSE/MMX support (yet).
+@c man begin OPTIONS
+@var{disk_image} is a raw hard disk image for IDE hard disk 0.
-@item No x86-64 support.
+General options:
+@table @option
+@item -M machine
+Select the emulated machine (@code{-M ?} for list)
-@item IPC syscalls are missing.
+@item -fda file
+@item -fdb file
+Use @var{file} as floppy disk 0/1 image (@xref{disk_images}). You can
+use the host floppy by using @file{/dev/fd0} as filename.
-@item The x86 segment limits and access rights are not tested at every
-memory access.
+@item -hda file
+@item -hdb file
+@item -hdc file
+@item -hdd file
+Use @var{file} as hard disk 0, 1, 2 or 3 image (@xref{disk_images}).
-@item On non x86 host CPUs, @code{double}s are used instead of the non standard
-10 byte @code{long double}s of x86 for floating point emulation to get
-maximum performances.
+@item -cdrom file
+Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and and
+@option{-cdrom} at the same time). You can use the host CD-ROM by
+using @file{/dev/cdrom} as filename.
-@item Some priviledged instructions or behaviors are missing, especially for segment protection testing (yet).
+@item -boot [a|c|d]
+Boot on floppy (a), hard disk (c) or CD-ROM (d). Hard disk boot is
+the default.
-@end itemize
+@item -snapshot
+Write to temporary files instead of disk image files. In this case,
+the raw disk image you use is not written back. You can however force
+the write back by pressing @key{C-a s} (@xref{disk_images}).
-@section ARM emulation
+@item -m megs
+Set virtual RAM size to @var{megs} megabytes. Default is 128 MB.
-@itemize
+@item -nographic
-@item ARM emulation can currently launch small programs while using the
-generic dynamic code generation architecture of QEMU.
+Normally, QEMU uses SDL to display the VGA output. With this option,
+you can totally disable graphical output so that QEMU is a simple
+command line application. The emulated serial port is redirected on
+the console. Therefore, you can still use QEMU to debug a Linux kernel
+with a serial console.
-@item No FPU support (yet).
+@item -k language
-@item No automatic regression testing (yet).
+Use keyboard layout @var{language} (for example @code{fr} for
+French). This option is only needed where it is not easy to get raw PC
+keycodes (e.g. on Macs or with some X11 servers). You don't need to
+use it on PC/Linux or PC/Windows hosts.
-@end itemize
+The available layouts are:
+@example
+ar de-ch es fo fr-ca hu ja mk no pt-br sv
+da en-gb et fr fr-ch is lt nl pl ru th
+de en-us fi fr-be hr it lv nl-be pt sl tr
+@end example
-@section SPARC emulation
+The default is @code{en-us}.
-The SPARC emulation is currently in development.
+@item -enable-audio
-@chapter Installation
+Will enable audio and all the sound hardware QEMU was built with.
+
+@item -audio-help
+
+Will show the audio subsystem help: list of drivers, tunable
+parameters.
-If you want to compile QEMU, please read the @file{README} which gives
-the related information. Otherwise just download the binary
-distribution (@file{qemu-XXX-i386.tar.gz}) and untar it as root in
-@file{/}:
+@item -soundhw card1,card2,...
+
+Enable audio and selected sound hardware. Use ? to print all
+available sound hardware.
@example
-su
-cd /
-tar zxvf /tmp/qemu-XXX-i386.tar.gz
+qemu -soundhw sb16,adlib hda
+qemu -soundhw es1370 hda
+qemu -soundhw ?
@end example
-@chapter QEMU User space emulator invocation
+@item -localtime
+Set the real time clock to local time (the default is to UTC
+time). This option is needed to have correct date in MS-DOS or
+Windows.
-@section Quick Start
+@item -full-screen
+Start in full screen.
-In order to launch a Linux process, QEMU needs the process executable
-itself and all the target (x86) dynamic libraries used by it.
+@item -pidfile file
+Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
+from a script.
-@itemize
+@item -win2k-hack
+Use it when installing Windows 2000 to avoid a disk full bug. After
+Windows 2000 is installed, you no longer need this option (this option
+slows down the IDE transfers).
-@item On x86, you can just try to launch any process by using the native
-libraries:
+@end table
-@example
-qemu-i386 -L / /bin/ls
-@end example
+USB options:
+@table @option
-@code{-L /} tells that the x86 dynamic linker must be searched with a
-@file{/} prefix.
+@item -usb
+Enable the USB driver (will be the default soon)
-@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):
+@item -usbdevice devname
+Add the USB device @var{devname}. See the monitor command
+@code{usb_add} to have more information.
+@end table
-@example
-qemu-i386 -L / qemu-i386 -L / /bin/ls
-@end example
+Network options:
-@item On non x86 CPUs, you need first to download at least an x86 glibc
-(@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
-@code{LD_LIBRARY_PATH} is not set:
+@table @option
-@example
-unset LD_LIBRARY_PATH
-@end example
+@item -net nic[,vlan=n][,macaddr=addr]
+Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
+= 0 is the default). The NIC is currently an NE2000 on the PC
+target. Optionally, the MAC address can be changed. If no
+@option{-net} option is specified, a single NIC is created.
-Then you can launch the precompiled @file{ls} x86 executable:
+@item -net user[,vlan=n]
+Use the user mode network stack which requires no administrator
+priviledge to run. This is the default if no @option{-net} option is
+specified.
+
+@item -net tap[,vlan=n][,fd=h][,ifname=name][,script=file]
+Connect the host TAP network interface @var{name} to VLAN @var{n} and
+use the network script @var{file} to configure it. The default
+network script is @file{/etc/qemu-ifup}. If @var{name} is not
+provided, the OS automatically provides one. @option{fd=h} can be
+used to specify the handle of an already opened host TAP interface. Example:
@example
-qemu-i386 tests/i386/ls
+qemu linux.img -net nic -net tap
@end example
-You can look at @file{qemu-binfmt-conf.sh} so that
-QEMU is automatically launched by the Linux kernel when you try to
-launch x86 executables. It requires the @code{binfmt_misc} module in the
-Linux kernel.
-@item The x86 version of QEMU is also included. You can try weird things such as:
+More complicated example (two NICs, each one connected to a TAP device)
@example
-qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 /usr/local/qemu-i386/bin/ls-i386
+qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
+ -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
@end example
-@end itemize
-@section Wine launch
+@item -net socket[,vlan=n][,fd=h][,listen=[host]:port][,connect=host:port]
-@itemize
+Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
+machine using a TCP socket connection. If @option{listen} is
+specified, QEMU waits for incoming connections on @var{port}
+(@var{host} is optional). @option{connect} is used to connect to
+another QEMU instance using the @option{listen} option. @option{fd=h}
+specifies an already opened socket.
-@item Ensure that you have a working QEMU with the x86 glibc
-distribution (see previous section). In order to verify it, you must be
-able to do:
+Example:
+@example
+# launch a first QEMU instance
+qemu linux.img -net nic,macaddr=52:54:00:12:34:56 -net socket,listen=:1234
+# connect the VLAN 0 of this instance to the VLAN 0 of the first instance
+qemu linux.img -net nic,macaddr=52:54:00:12:34:57 -net socket,connect=127.0.0.1:1234
+@end example
+@item -net none
+Indicate that no network devices should be configured. It is used to
+override the default configuration which is activated if no
+@option{-net} options are provided.
+
+@item -tftp prefix
+When using the user mode network stack, activate a built-in TFTP
+server. All filenames beginning with @var{prefix} can be downloaded
+from the host to the guest using a TFTP client. The TFTP client on the
+guest must be configured in binary mode (use the command @code{bin} of
+the Unix TFTP client). The host IP address on the guest is as usual
+10.0.2.2.
+
+@item -smb dir
+When using the user mode network stack, activate a built-in SMB
+server so that Windows OSes can access to the host files in @file{dir}
+transparently.
+
+In the guest Windows OS, the line:
@example
-qemu-i386 /usr/local/qemu-i386/bin/ls-i386
+10.0.2.4 smbserver
@end example
+must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
+or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
-@item Download the binary x86 Wine install
-(@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
+Then @file{dir} can be accessed in @file{\\smbserver\qemu}.
-@item Configure Wine on your account. Look at the provided script
-@file{/usr/local/qemu-i386/bin/wine-conf.sh}. Your previous
-@code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
+Note that a SAMBA server must be installed on the host OS in
+@file{/usr/sbin/smbd}. QEMU was tested succesfully with smbd version
+2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core 3.
-@item Then you can try the example @file{putty.exe}:
+@item -redir [tcp|udp]:host-port:[guest-host]:guest-port
+
+When using the user mode network stack, redirect incoming TCP or UDP
+connections to the host port @var{host-port} to the guest
+@var{guest-host} on guest port @var{guest-port}. If @var{guest-host}
+is not specified, its value is 10.0.2.15 (default address given by the
+built-in DHCP server).
+
+For example, to redirect host X11 connection from screen 1 to guest
+screen 0, use the following:
@example
-qemu-i386 /usr/local/qemu-i386/wine/bin/wine /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
+# on the host
+qemu -redir tcp:6001::6000 [...]
+# this host xterm should open in the guest X11 server
+xterm -display :1
@end example
-@end itemize
-
-@section Command line options
+To redirect telnet connections from host port 5555 to telnet port on
+the guest, use the following:
@example
-usage: qemu-i386 [-h] [-d] [-L path] [-s size] program [arguments...]
+# on the host
+qemu -redir tcp:5555::23 [...]
+telnet localhost 5555
@end example
-@table @option
-@item -h
-Print the help
-@item -L path
-Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
-@item -s size
-Set the x86 stack size in bytes (default=524288)
+Then when you use on the host @code{telnet localhost 5555}, you
+connect to the guest telnet server.
+
@end table
-Debug options:
+Linux boot specific: When using these options, you can use a given
+Linux kernel without installing it in the disk image. It can be useful
+for easier testing of various kernels.
@table @option
-@item -d
-Activate log (logfile=/tmp/qemu.log)
-@item -p pagesize
-Act as if the host page size was 'pagesize' bytes
+
+@item -kernel bzImage
+Use @var{bzImage} as kernel image.
+
+@item -append cmdline
+Use @var{cmdline} as kernel command line
+
+@item -initrd file
+Use @var{file} as initial ram disk.
+
@end table
-@chapter QEMU System emulator invocation
+Debug/Expert options:
+@table @option
-@section Introduction
+@item -serial dev
+Redirect the virtual serial port to host device @var{dev}. Available
+devices are:
+@table @code
+@item vc
+Virtual console
+@item pty
+[Linux only] Pseudo TTY (a new PTY is automatically allocated)
+@item null
+void device
+@item /dev/XXX
+[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
+parameters are set according to the emulated ones.
+@item /dev/parportN
+[Linux only, parallel port only] Use host parallel port
+@var{N}. Currently only SPP parallel port features can be used.
+@item file:filename
+Write output to filename. No character can be read.
+@item stdio
+[Unix only] standard input/output
+@item pipe:filename
+[Unix only] name pipe @var{filename}
+@end table
+The default device is @code{vc} in graphical mode and @code{stdio} in
+non graphical mode.
-@c man begin DESCRIPTION
+This option can be used several times to simulate up to 4 serials
+ports.
-The QEMU System emulator simulates a complete PC. It can either boot
-directly a Linux kernel (without any BIOS or boot loader) or boot like a
-real PC with the included BIOS.
+@item -parallel dev
+Redirect the virtual parallel port to host device @var{dev} (same
+devices as the serial port). On Linux hosts, @file{/dev/parportN} can
+be used to use hardware devices connected on the corresponding host
+parallel port.
-In order to meet specific user needs, two versions of QEMU are
-available:
+This option can be used several times to simulate up to 3 parallel
+ports.
-@enumerate
+@item -monitor dev
+Redirect the monitor to host device @var{dev} (same devices as the
+serial port).
+The default device is @code{vc} in graphical mode and @code{stdio} in
+non graphical mode.
-@item
-@code{qemu-fast} uses the host Memory Management Unit (MMU) to simulate
-the x86 MMU. It is @emph{fast} but has limitations because the whole 4 GB
-address space cannot be used and some memory mapped peripherials
-cannot be emulated accurately yet. Therefore, a specific Linux kernel
-must be used (@xref{linux_compile}).
+@item -s
+Wait gdb connection to port 1234 (@xref{gdb_usage}).
+@item -p port
+Change gdb connection port.
+@item -S
+Do not start CPU at startup (you must type 'c' in the monitor).
+@item -d
+Output log in /tmp/qemu.log
+@item -hdachs c,h,s,[,t]
+Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
+@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
+translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
+all thoses parameters. This option is useful for old MS-DOS disk
+images.
+
+@item -std-vga
+Simulate a standard VGA card with Bochs VBE extensions (default is
+Cirrus Logic GD5446 PCI VGA)
+@item -loadvm file
+Start right away with a saved state (@code{loadvm} in monitor)
+@end table
-@item
-@code{qemu} uses a software MMU. It is about @emph{two times
-slower} but gives a more accurate emulation.
+@c man end
-@end enumerate
+@section Keys
+
+@c man begin OPTIONS
+
+During the graphical emulation, you can use the following keys:
+@table @key
+@item Ctrl-Alt-f
+Toggle full screen
+
+@item Ctrl-Alt-n
+Switch to virtual console 'n'. Standard console mappings are:
+@table @emph
+@item 1
+Target system display
+@item 2
+Monitor
+@item 3
+Serial port
+@end table
-QEMU emulates the following PC peripherials:
+@item Ctrl-Alt
+Toggle mouse and keyboard grab.
+@end table
+
+In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
+@key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
+
+During emulation, if you are using the @option{-nographic} option, use
+@key{Ctrl-a h} to get terminal commands:
+
+@table @key
+@item Ctrl-a h
+Print this help
+@item Ctrl-a x
+Exit emulatior
+@item Ctrl-a s
+Save disk data back to file (if -snapshot)
+@item Ctrl-a b
+Send break (magic sysrq in Linux)
+@item Ctrl-a c
+Switch between console and monitor
+@item Ctrl-a Ctrl-a
+Send Ctrl-a
+@end table
+@c man end
+
+@ignore
+
+@setfilename qemu
+@settitle QEMU System Emulator
+
+@c man begin SEEALSO
+The HTML documentation of QEMU for more precise information and Linux
+user mode emulator invocation.
+@c man end
+
+@c man begin AUTHOR
+Fabrice Bellard
+@c man end
+
+@end ignore
+
+@end ignore
+
+@section QEMU Monitor
+
+The QEMU monitor is used to give complex commands to the QEMU
+emulator. You can use it to:
@itemize @minus
+
@item
-VGA (hardware level, including all non standard modes)
-@item
-PS/2 mouse and keyboard
-@item
-IDE disk interface (port=0x1f0, irq=14)
+Remove or insert removable medias images
+(such as CD-ROM or floppies)
+
@item
-NE2000 network adapter (port=0x300, irq=9)
-@item
-Serial port (port=0x3f8, irq=4)
+Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
+from a disk file.
+
+@item Inspect the VM state without an external debugger.
+
+@end itemize
+
+@subsection Commands
+
+The following commands are available:
+
+@table @option
+
+@item help or ? [cmd]
+Show the help for all commands or just for command @var{cmd}.
+
+@item commit
+Commit changes to the disk images (if -snapshot is used)
+
+@item info subcommand
+show various information about the system state
+
+@table @option
+@item info network
+show the various VLANs and the associated devices
+@item info block
+show the block devices
+@item info registers
+show the cpu registers
+@item info history
+show the command line history
+@item info pci
+show emulated PCI device
+@item info usb
+show USB devices plugged on the virtual USB hub
+@item info usbhost
+show all USB host devices
+@end table
+
+@item q or quit
+Quit the emulator.
+
+@item eject [-f] device
+Eject a removable media (use -f to force it).
+
+@item change device filename
+Change a removable media.
+
+@item screendump filename
+Save screen into PPM image @var{filename}.
+
+@item log item1[,...]
+Activate logging of the specified items to @file{/tmp/qemu.log}.
+
+@item savevm filename
+Save the whole virtual machine state to @var{filename}.
+
+@item loadvm filename
+Restore the whole virtual machine state from @var{filename}.
+
+@item stop
+Stop emulation.
+
+@item c or cont
+Resume emulation.
+
+@item gdbserver [port]
+Start gdbserver session (default port=1234)
+
+@item x/fmt addr
+Virtual memory dump starting at @var{addr}.
+
+@item xp /fmt addr
+Physical memory dump starting at @var{addr}.
+
+@var{fmt} is a format which tells the command how to format the
+data. Its syntax is: @option{/@{count@}@{format@}@{size@}}
+
+@table @var
+@item count
+is the number of items to be dumped.
+
+@item format
+can be x (hexa), d (signed decimal), u (unsigned decimal), o (octal),
+c (char) or i (asm instruction).
+
+@item size
+can be b (8 bits), h (16 bits), w (32 bits) or g (64 bits). On x86,
+@code{h} or @code{w} can be specified with the @code{i} format to
+respectively select 16 or 32 bit code instruction size.
+
+@end table
+
+Examples:
+@itemize
@item
-PIC (interrupt controler)
+Dump 10 instructions at the current instruction pointer:
+@example
+(qemu) x/10i $eip
+0x90107063: ret
+0x90107064: sti
+0x90107065: lea 0x0(%esi,1),%esi
+0x90107069: lea 0x0(%edi,1),%edi
+0x90107070: ret
+0x90107071: jmp 0x90107080
+0x90107073: nop
+0x90107074: nop
+0x90107075: nop
+0x90107076: nop
+@end example
+
@item
-PIT (timers)
-@item
-CMOS memory
+Dump 80 16 bit values at the start of the video memory.
+@example
+(qemu) xp/80hx 0xb8000
+0x000b8000: 0x0b50 0x0b6c 0x0b65 0x0b78 0x0b38 0x0b36 0x0b2f 0x0b42
+0x000b8010: 0x0b6f 0x0b63 0x0b68 0x0b73 0x0b20 0x0b56 0x0b47 0x0b41
+0x000b8020: 0x0b42 0x0b69 0x0b6f 0x0b73 0x0b20 0x0b63 0x0b75 0x0b72
+0x000b8030: 0x0b72 0x0b65 0x0b6e 0x0b74 0x0b2d 0x0b63 0x0b76 0x0b73
+0x000b8040: 0x0b20 0x0b30 0x0b35 0x0b20 0x0b4e 0x0b6f 0x0b76 0x0b20
+0x000b8050: 0x0b32 0x0b30 0x0b30 0x0b33 0x0720 0x0720 0x0720 0x0720
+0x000b8060: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
+0x000b8070: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
+0x000b8080: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
+0x000b8090: 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720 0x0720
+@end example
@end itemize
-@c man end
+@item p or print/fmt expr
-@section Quick Start
+Print expression value. Only the @var{format} part of @var{fmt} is
+used.
-Download and uncompress the linux image (@file{linux.img}) and type:
+@item sendkey keys
+Send @var{keys} to the emulator. Use @code{-} to press several keys
+simultaneously. Example:
@example
-qemu linux.img
+sendkey ctrl-alt-f1
@end example
-Linux should boot and give you a prompt.
+This command is useful to send keys that your graphical user interface
+intercepts at low level, such as @code{ctrl-alt-f1} in X Window.
+
+@item system_reset
+
+Reset the system.
+
+@item usb_add devname
+
+Plug the USB device devname to the QEMU virtual USB hub. @var{devname}
+is either a virtual device name (for example @code{mouse}) or a host
+USB device identifier. Host USB device identifiers have the following
+syntax: @code{host:bus.addr} or @code{host:vendor_id:product_id}.
+
+@item usb_del devname
+
+Remove the USB device @var{devname} from the QEMU virtual USB
+hub. @var{devname} has the syntax @code{bus.addr}. Use the monitor
+command @code{info usb} to see the devices you can remove.
+
+@end table
+
+@subsection Integer expressions
+
+The monitor understands integers expressions for every integer
+argument. You can use register names to get the value of specifics
+CPU registers by prefixing them with @emph{$}.
+
+@node disk_images
+@section Disk Images
+
+Since version 0.6.1, QEMU supports many disk image formats, including
+growable disk images (their size increase as non empty sectors are
+written), compressed and encrypted disk images.
+
+@subsection Quick start for disk image creation
+
+You can create a disk image with the command:
+@example
+qemu-img create myimage.img mysize
+@end example
+where @var{myimage.img} is the disk image filename and @var{mysize} is its
+size in kilobytes. You can add an @code{M} suffix to give the size in
+megabytes and a @code{G} suffix for gigabytes.
+
+@xref{qemu_img_invocation} for more information.
+
+@subsection Snapshot mode
+
+If you use the option @option{-snapshot}, all disk images are
+considered as read only. When sectors in written, they are written in
+a temporary file created in @file{/tmp}. You can however force the
+write back to the raw disk images by using the @code{commit} monitor
+command (or @key{C-a s} in the serial console).
+
+@node qemu_img_invocation
+@subsection @code{qemu-img} Invocation
+
+@include qemu-img.texi
+
+@section Network emulation
-@section Direct Linux Boot and Network emulation
+QEMU can simulate several networks cards (NE2000 boards on the PC
+target) and can connect them to an arbitrary number of Virtual Local
+Area Networks (VLANs). Host TAP devices can be connected to any QEMU
+VLAN. VLAN can be connected between separate instances of QEMU to
+simulate large networks. For simpler usage, a non priviledged user mode
+network stack can replace the TAP device to have a basic network
+connection.
+
+@subsection VLANs
+
+QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
+connection between several network devices. These devices can be for
+example QEMU virtual Ethernet cards or virtual Host ethernet devices
+(TAP devices).
+
+@subsection Using TAP network interfaces
+
+This is the standard way to connect QEMU to a real network. QEMU adds
+a virtual network device on your host (called @code{tapN}), and you
+can then configure it as if it was a real ethernet card.
+
+As an example, you can download the @file{linux-test-xxx.tar.gz}
+archive and copy the script @file{qemu-ifup} in @file{/etc} and
+configure properly @code{sudo} so that the command @code{ifconfig}
+contained in @file{qemu-ifup} can be executed as root. You must verify
+that your host kernel supports the TAP network interfaces: the
+device @file{/dev/net/tun} must be present.
+
+See @ref{direct_linux_boot} to have an example of network use with a
+Linux distribution and @ref{sec_invocation} to have examples of
+command lines using the TAP network interfaces.
+
+@subsection Using the user mode network stack
+
+By using the option @option{-net user} (default configuration if no
+@option{-net} option is specified), QEMU uses a completely user mode
+network stack (you don't need root priviledge to use the virtual
+network). The virtual network configuration is the following:
+
+@example
+
+ QEMU VLAN <------> Firewall/DHCP server <-----> Internet
+ | (10.0.2.2)
+ |
+ ----> DNS server (10.0.2.3)
+ |
+ ----> SMB server (10.0.2.4)
+@end example
+
+The QEMU VM behaves as if it was behind a firewall which blocks all
+incoming connections. You can use a DHCP client to automatically
+configure the network in the QEMU VM. The DHCP server assign addresses
+to the hosts starting from 10.0.2.15.
+
+In order to check that the user mode network is working, you can ping
+the address 10.0.2.2 and verify that you got an address in the range
+10.0.2.x from the QEMU virtual DHCP server.
+
+Note that @code{ping} is not supported reliably to the internet as it
+would require root priviledges. It means you can only ping the local
+router (10.0.2.2).
+
+When using the built-in TFTP server, the router is also the TFTP
+server.
+
+When using the @option{-redir} option, TCP or UDP connections can be
+redirected from the host to the guest. It allows for example to
+redirect X11, telnet or SSH connections.
+
+@subsection Connecting VLANs between QEMU instances
+
+Using the @option{-net socket} option, it is possible to make VLANs
+that span several QEMU instances. See @ref{sec_invocation} to have a
+basic example.
+
+@node direct_linux_boot
+@section Direct Linux Boot
This section explains how to launch a Linux kernel inside QEMU without
having to make a full bootable image. It is very useful for fast Linux
@example
> ./qemu.sh
-connected to host network interface: tun0
-Uncompressing Linux... Ok, booting the kernel.
-Linux version 2.4.20 (fabrice@localhost.localdomain) (gcc version 2.96 20000731 (Red Hat Linux 7.3 2.96-110)) #22 lun jui 7 13:37:41 CEST 2003
+Connected to host network interface: tun0
+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
BIOS-provided physical RAM map:
BIOS-e801: 0000000000000000 - 000000000009f000 (usable)
BIOS-e801: 0000000000100000 - 0000000002000000 (usable)
zone(0): 4096 pages.
zone(1): 4096 pages.
zone(2): 0 pages.
-Kernel command line: root=/dev/hda ide1=noprobe ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe
-ide_setup: ide1=noprobe
+Kernel command line: root=/dev/hda sb=0x220,5,1,5 ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe console=ttyS0
ide_setup: ide2=noprobe
ide_setup: ide3=noprobe
ide_setup: ide4=noprobe
ide_setup: ide5=noprobe
Initializing CPU#0
-Detected 501.285 MHz processor.
-Calibrating delay loop... 989.59 BogoMIPS
-Memory: 29268k/32768k available (907k kernel code, 3112k reserved, 212k data, 52k init, 0k highmem)
+Detected 2399.621 MHz processor.
+Console: colour EGA 80x25
+Calibrating delay loop... 4744.80 BogoMIPS
+Memory: 28872k/32768k available (1210k kernel code, 3508k reserved, 266k data, 64k init, 0k highmem)
Dentry cache hash table entries: 4096 (order: 3, 32768 bytes)
Inode cache hash table entries: 2048 (order: 2, 16384 bytes)
-Mount-cache hash table entries: 512 (order: 0, 4096 bytes)
+Mount cache hash table entries: 512 (order: 0, 4096 bytes)
Buffer-cache hash table entries: 1024 (order: 0, 4096 bytes)
Page-cache hash table entries: 8192 (order: 3, 32768 bytes)
CPU: Intel Pentium Pro stepping 03
apm: BIOS not found.
Starting kswapd
Journalled Block Device driver loaded
+Detected PS/2 Mouse Port.
pty: 256 Unix98 ptys configured
Serial driver version 5.05c (2001-07-08) with no serial options enabled
ttyS00 at 0x03f8 (irq = 4) is a 16450
-Uniform Multi-Platform E-IDE driver Revision: 6.31
-ide: Assuming 50MHz system bus speed for PIO modes; override with idebus=xx
-hda: QEMU HARDDISK, ATA DISK drive
-ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
-hda: 12288 sectors (6 MB) w/256KiB Cache, CHS=12/16/63
-Partition check:
- hda: unknown partition table
ne.c:v1.10 9/23/94 Donald Becker (becker@scyld.com)
Last modified Nov 1, 2000 by Paul Gortmaker
NE*000 ethercard probe at 0x300: 52 54 00 12 34 56
eth0: NE2000 found at 0x300, using IRQ 9.
RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
+Uniform Multi-Platform E-IDE driver Revision: 7.00beta4-2.4
+ide: Assuming 50MHz system bus speed for PIO modes; override with idebus=xx
+hda: QEMU HARDDISK, ATA DISK drive
+ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
+hda: attached ide-disk driver.
+hda: 20480 sectors (10 MB) w/256KiB Cache, CHS=20/16/63
+Partition check:
+ hda:
+Soundblaster audio driver Copyright (C) by Hannu Savolainen 1993-1996
NET4: Linux TCP/IP 1.0 for NET4.0
IP Protocols: ICMP, UDP, TCP, IGMP
IP: routing cache hash table of 512 buckets, 4Kbytes
NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
EXT2-fs warning: mounting unchecked fs, running e2fsck is recommended
VFS: Mounted root (ext2 filesystem).
-Freeing unused kernel memory: 52k freed
-sh: can't access tty; job control turned off
-#
+Freeing unused kernel memory: 64k freed
+
+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
+
+QEMU Linux test distribution (based on Redhat 9)
+
+Type 'exit' to halt the system
+
+sh-2.05b#
@end example
@item
Then you can play with the kernel inside the virtual serial console. You
can launch @code{ls} for example. Type @key{Ctrl-a h} to have an help
about the keys you can type inside the virtual serial console. In
-particular, use @key{Ctrl-a x} to exit QEMU and use @key{Ctrl-a b} as
-the Magic SysRq key.
-
-@item
-If the network is enabled, launch the script @file{/etc/linuxrc} in the
-emulator (don't forget the leading dot):
-@example
-. /etc/linuxrc
-@end example
-
-Then enable X11 connections on your PC from the emulated Linux:
-@example
-xhost +172.20.0.2
-@end example
-
-You can now launch @file{xterm} or @file{xlogo} and verify that you have
-a real Virtual Linux system !
-
-@end enumerate
-
-NOTES:
-@enumerate
-@item
-A 2.5.74 kernel is also included in the archive. Just
-replace the bzImage in qemu.sh to try it.
-
-@item
-vl creates a temporary file in @var{$QEMU_TMPDIR} (@file{/tmp} is the
-default) containing all the simulated PC memory. If possible, try to use
-a temporary directory using the tmpfs filesystem to avoid too many
-unnecessary disk accesses.
-
-@item
-In order to exit cleanly for vl, you can do a @emph{shutdown} inside
-vl. vl will automatically exit when the Linux shutdown is done.
-
-@item
-You can boot slightly faster by disabling the probe of non present IDE
-interfaces. To do so, add the following options on the kernel command
-line:
-@example
-ide1=noprobe ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe
-@end example
-
-@item
-The example disk image is a modified version of the one made by Kevin
-Lawton for the plex86 Project (@url{www.plex86.org}).
-
-@end enumerate
-
-@section Invocation
-
-@example
-@c man begin SYNOPSIS
-usage: qemu [options] [disk_image]
-@c man end
-@end example
-
-@c man begin OPTIONS
-@var{disk_image} is a raw hard image image for IDE hard disk 0.
-
-General options:
-@table @option
-@item -hda file
-@item -hdb file
-Use @var{file} as hard disk 0 or 1 image (@xref{disk_images}).
-
-@item -snapshot
-
-Write to temporary files instead of disk image files. In this case,
-the raw disk image you use is not written back. You can however force
-the write back by pressing @key{C-a s} (@xref{disk_images}).
-
-@item -m megs
-Set virtual RAM size to @var{megs} megabytes.
-
-@item -n script
-Set network init script [default=/etc/vl-ifup]. This script is
-launched to configure the host network interface (usually tun0)
-corresponding to the virtual NE2000 card.
-
-@item -initrd file
-Use @var{file} as initial ram disk.
-
-@item -tun-fd fd
-Assumes @var{fd} talks to tap/tun and use it. Read
-@url{http://bellard.org/qemu/tetrinet.html} to have an example of its
-use.
-
-@item -nographic
-
-Normally, QEMU uses SDL to display the VGA output. With this option,
-you can totally disable graphical output so that QEMU is a simple
-command line application. The emulated serial port is redirected on
-the console. Therefore, you can still use QEMU to debug a Linux kernel
-with a serial console.
-
-@end table
-
-Linux boot specific (does not require a full PC boot with a BIOS):
-@table @option
-
-@item -kernel bzImage
-Use @var{bzImage} as kernel image.
-
-@item -append cmdline
-Use @var{cmdline} as kernel command line
-
-@item -initrd file
-Use @var{file} as initial ram disk.
-
-@end table
-
-Debug options:
-@table @option
-@item -s
-Wait gdb connection to port 1234 (@xref{gdb_usage}).
-@item -p port
-Change gdb connection port.
-@item -d
-Output log in /tmp/vl.log
-@end table
-
-During emulation, use @key{C-a h} to get terminal commands:
-
-@table @key
-@item C-a h
-Print this help
-@item C-a x
-Exit emulatior
-@item C-a s
-Save disk data back to file (if -snapshot)
-@item C-a b
-Send break (magic sysrq)
-@item C-a C-a
-Send C-a
-@end table
-@c man end
-
-@ignore
-
-@setfilename qemu
-@settitle QEMU System Emulator
-
-@c man begin SEEALSO
-The HTML documentation of QEMU for more precise information and Linux
-user mode emulator invocation.
-@c man end
-
-@c man begin AUTHOR
-Fabrice Bellard
-@c man end
-
-@end ignore
-
-@end ignore
-@node disk_images
-@section Disk Images
-
-@subsection Raw disk images
+particular, use @key{Ctrl-a x} to exit QEMU and use @key{Ctrl-a b} as
+the Magic SysRq key.
-The disk images can simply be raw images of the hard disk. You can
-create them with the command:
+@item
+If the network is enabled, launch the script @file{/etc/linuxrc} in the
+emulator (don't forget the leading dot):
@example
-dd if=/dev/zero of=myimage bs=1024 count=mysize
+. /etc/linuxrc
@end example
-where @var{myimage} is the image filename and @var{mysize} is its size
-in kilobytes.
-
-@subsection Snapshot mode
-If you use the option @option{-snapshot}, all disk images are
-considered as read only. When sectors in written, they are written in
-a temporary file created in @file{/tmp}. You can however force the
-write back to the raw disk images by pressing @key{C-a s}.
+Then enable X11 connections on your PC from the emulated Linux:
+@example
+xhost +172.20.0.2
+@end example
-NOTE: The snapshot mode only works with raw disk images.
+You can now launch @file{xterm} or @file{xlogo} and verify that you have
+a real Virtual Linux system !
-@subsection Copy On Write disk images
+@end enumerate
-QEMU also supports user mode Linux
-(@url{http://user-mode-linux.sourceforge.net/}) Copy On Write (COW)
-disk images. The COW disk images are much smaller than normal images
-as they store only modified sectors. They also permit the use of the
-same disk image template for many users.
+NOTES:
+@enumerate
+@item
+A 2.5.74 kernel is also included in the archive. Just
+replace the bzImage in qemu.sh to try it.
-To create a COW disk images, use the command:
+@item
+In order to exit cleanly from qemu, you can do a @emph{shutdown} inside
+qemu. qemu will automatically exit when the Linux shutdown is done.
+@item
+You can boot slightly faster by disabling the probe of non present IDE
+interfaces. To do so, add the following options on the kernel command
+line:
@example
-qemu-mkcow -f myrawimage.bin mycowimage.cow
+ide1=noprobe ide2=noprobe ide3=noprobe ide4=noprobe ide5=noprobe
@end example
-@file{myrawimage.bin} is a raw image you want to use as original disk
-image. It will never be written to.
+@item
+The example disk image is a modified version of the one made by Kevin
+Lawton for the plex86 Project (@url{www.plex86.org}).
+
+@end enumerate
+
+@section USB emulation
+
+QEMU emulates a PCI UHCI USB controller and a 8 port USB hub connected
+to it. You can virtually plug to the hub virtual USB devices or real
+host USB devices (experimental, works only on Linux hosts).
-@file{mycowimage.cow} is the COW disk image which is created by
-@code{qemu-mkcow}. You can use it directly with the @option{-hdx}
-options. You must not modify the original raw disk image if you use
-COW images, as COW images only store the modified sectors from the raw
-disk image. QEMU stores the original raw disk image name and its
-modified time in the COW disk image so that chances of mistakes are
-reduced.
+@subsection Using virtual USB devices
-If the raw disk image is not read-only, by pressing @key{C-a s} you
-can flush the COW disk image back into the raw disk image, as in
-snapshot mode.
+A virtual USB mouse device is available for testing in QEMU.
-COW disk images can also be created without a corresponding raw disk
-image. It is useful to have a big initial virtual disk image without
-using much disk space. Use:
+You can try it with the following monitor commands:
@example
-qemu-mkcow mycowimage.cow 1024
-@end example
+# add the mouse device
+(qemu) usb_add mouse
-to create a 1 gigabyte empty COW disk image.
+# show the virtual USB devices plugged on the QEMU Virtual USB hub
+(qemu) info usb
+ Device 0.3, speed 12 Mb/s
-NOTES:
-@enumerate
-@item
-COW disk images must be created on file systems supporting
-@emph{holes} such as ext2 or ext3.
-@item
-Since holes are used, the displayed size of the COW disk image is not
-the real one. To know it, use the @code{ls -ls} command.
-@end enumerate
+# after some time you can try to remove the mouse
+(qemu) usb_del 0.3
+@end example
-@node linux_compile
-@section Linux Kernel Compilation
+The option @option{-usbdevice} is similar to the monitor command
+@code{usb_add}.
-You can use any linux kernel with QEMU. However, if you want to use
-@code{qemu-fast} to get maximum performances, you should make the
-following changes to the Linux kernel (only 2.4.x and 2.5.x were
-tested):
+@subsection Using host USB devices on a Linux host
+
+WARNING: this is an experimental feature. QEMU will slow down when
+using it. USB devices requiring real time streaming (i.e. USB Video
+Cameras) are not supported yet.
@enumerate
-@item
-The kernel must be mapped at 0x90000000 (the default is
-0xc0000000). You must modify only two lines in the kernel source:
+@item If you use an early Linux 2.4 kernel, verify that no Linux driver
+is actually using the USB device. A simple way to do that is simply to
+disable the corresponding kernel module by renaming it from @file{mydriver.o}
+to @file{mydriver.o.disabled}.
-In @file{include/asm/page.h}, replace
+@item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
@example
-#define __PAGE_OFFSET (0xc0000000)
-@end example
-by
-@example
-#define __PAGE_OFFSET (0x90000000)
+ls /proc/bus/usb
+001 devices drivers
@end example
-And in @file{arch/i386/vmlinux.lds}, replace
-@example
- . = 0xc0000000 + 0x100000;
-@end example
-by
+@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:
@example
- . = 0x90000000 + 0x100000;
+chown -R myuid /proc/bus/usb
@end example
-@item
-If you want to enable SMP (Symmetric Multi-Processing) support, you
-must make the following change in @file{include/asm/fixmap.h}. Replace
-@example
-#define FIXADDR_TOP (0xffffX000UL)
-@end example
-by
-@example
-#define FIXADDR_TOP (0xa7ffX000UL)
+@item Launch QEMU and do in the monitor:
+@example
+info usbhost
+ Device 1.2, speed 480 Mb/s
+ Class 00: USB device 1234:5678, USB DISK
@end example
-(X is 'e' or 'f' depending on the kernel version). Although you can
-use an SMP kernel with QEMU, it only supports one CPU.
-
-@item
-If you are not using a 2.5 kernel as host kernel but if you use a target
-2.5 kernel, you must also ensure that the 'HZ' define is set to 100
-(1000 is the default) as QEMU cannot currently emulate timers at
-frequencies greater than 100 Hz on host Linux systems < 2.5. In
-@file{include/asm/param.h}, replace:
+You should see the list of the devices you can use (Never try to use
+hubs, it won't work).
-@example
-# define HZ 1000 /* Internal kernel timer frequency */
-@end example
-by
-@example
-# define HZ 100 /* Internal kernel timer frequency */
+@item Add the device in QEMU by using:
+@example
+usb_add host:1234:5678
@end example
-@end enumerate
+Normally the guest OS should report that a new USB device is
+plugged. You can use the option @option{-usbdevice} to do the same.
-The file config-2.x.x gives the configuration of the example kernels.
+@item Now you can try to use the host USB device in QEMU.
-Just type
-@example
-make bzImage
-@end example
+@end enumerate
-As you would do to make a real kernel. Then you can use with QEMU
-exactly the same kernel as you would boot on your PC (in
-@file{arch/i386/boot/bzImage}).
+When relaunching QEMU, you may have to unplug and plug again the USB
+device to make it work again (this is a bug).
@node gdb_usage
@section GDB usage
QEMU has a primitive support to work with gdb, so that you can do
'Ctrl-C' while the virtual machine is running and inspect its state.
-In order to use gdb, launch vl with the '-s' option. It will wait for a
+In order to use gdb, launch qemu with the '-s' option. It will wait for a
gdb connection:
@example
-> vl -s arch/i386/boot/bzImage -hda root-2.4.20.img root=/dev/hda
+> qemu -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img -append "root=/dev/hda"
Connected to host network interface: tun0
Waiting gdb connection on port 1234
@end example
In gdb, connect to QEMU:
@example
-(gdb) target remote locahost:1234
+(gdb) target remote localhost:1234
@end example
Then you can use gdb normally. For example, type 'c' to launch the kernel:
@code{x/10i $cs*16+*eip} to dump the code at the PC position.
@end enumerate
-@chapter QEMU Internals
-
-@section QEMU compared to other emulators
-
-Like bochs [3], QEMU emulates an x86 CPU. But QEMU is much faster than
-bochs as it uses dynamic compilation and because it uses the host MMU to
-simulate the x86 MMU. The downside is that currently the emulation is
-not as accurate as bochs (for example, you cannot currently run Windows
-inside QEMU).
-
-Like Valgrind [2], QEMU does user space emulation and dynamic
-translation. Valgrind is mainly a memory debugger while QEMU has no
-support for it (QEMU could be used to detect out of bound memory
-accesses as Valgrind, but it has no support to track uninitialised data
-as Valgrind does). The Valgrind dynamic translator generates better code
-than QEMU (in particular it does register allocation) but it is closely
-tied to an x86 host and target and has no support for precise exceptions
-and system emulation.
-
-EM86 [4] is the closest project to user space QEMU (and QEMU still uses
-some of its code, in particular the ELF file loader). EM86 was limited
-to an alpha host and used a proprietary and slow interpreter (the
-interpreter part of the FX!32 Digital Win32 code translator [5]).
-
-TWIN [6] is a Windows API emulator like Wine. It is less accurate than
-Wine but includes a protected mode x86 interpreter to launch x86 Windows
-executables. Such an approach as greater potential because most of the
-Windows API is executed natively but it is far more difficult to develop
-because all the data structures and function parameters exchanged
-between the API and the x86 code must be converted.
-
-User mode Linux [7] was the only solution before QEMU to launch a Linux
-kernel as a process while not needing any host kernel patches. However,
-user mode Linux requires heavy kernel patches while QEMU accepts
-unpatched Linux kernels. It would be interesting to compare the
-performance of the two approaches.
-
-The new Plex86 [8] PC virtualizer is done in the same spirit as the QEMU
-system emulator. It requires a patched Linux kernel to work (you cannot
-launch the same kernel on your PC), but the patches are really small. As
-it is a PC virtualizer (no emulation is done except for some priveledged
-instructions), it has the potential of being faster than QEMU. The
-downside is that a complicated (and potentially unsafe) host kernel
-patch is needed.
-
-@section Portable dynamic translation
-
-QEMU is a dynamic translator. When it first encounters a piece of code,
-it converts it to the host instruction set. Usually dynamic translators
-are very complicated and highly CPU dependent. QEMU uses some tricks
-which make it relatively easily portable and simple while achieving good
-performances.
-
-The basic idea is to split every x86 instruction into fewer simpler
-instructions. Each simple instruction is implemented by a piece of C
-code (see @file{op-i386.c}). Then a compile time tool (@file{dyngen})
-takes the corresponding object file (@file{op-i386.o}) to generate a
-dynamic code generator which concatenates the simple instructions to
-build a function (see @file{op-i386.h:dyngen_code()}).
-
-In essence, the process is similar to [1], but more work is done at
-compile time.
-
-A key idea to get optimal performances is that constant parameters can
-be passed to the simple operations. For that purpose, dummy ELF
-relocations are generated with gcc for each constant parameter. Then,
-the tool (@file{dyngen}) can locate the relocations and generate the
-appriopriate C code to resolve them when building the dynamic code.
-
-That way, QEMU is no more difficult to port than a dynamic linker.
-
-To go even faster, GCC static register variables are used to keep the
-state of the virtual CPU.
-
-@section Register allocation
-
-Since QEMU uses fixed simple instructions, no efficient register
-allocation can be done. However, because RISC CPUs have a lot of
-register, most of the virtual CPU state can be put in registers without
-doing complicated register allocation.
-
-@section Condition code optimisations
-
-Good CPU condition codes emulation (@code{EFLAGS} register on x86) is a
-critical point to get good performances. QEMU uses lazy condition code
-evaluation: instead of computing the condition codes after each x86
-instruction, it just stores one operand (called @code{CC_SRC}), the
-result (called @code{CC_DST}) and the type of operation (called
-@code{CC_OP}).
-
-@code{CC_OP} is almost never explicitely set in the generated code
-because it is known at translation time.
-
-In order to increase performances, a backward pass is performed on the
-generated simple instructions (see
-@code{translate-i386.c:optimize_flags()}). When it can be proved that
-the condition codes are not needed by the next instructions, no
-condition codes are computed at all.
-
-@section CPU state optimisations
-
-The x86 CPU has many internal states which change the way it evaluates
-instructions. In order to achieve a good speed, the translation phase
-considers that some state information of the virtual x86 CPU cannot
-change in it. For example, if the SS, DS and ES segments have a zero
-base, then the translator does not even generate an addition for the
-segment base.
-
-[The FPU stack pointer register is not handled that way yet].
-
-@section Translation cache
-
-A 2MByte cache holds the most recently used translations. For
-simplicity, it is completely flushed when it is full. A translation unit
-contains just a single basic block (a block of x86 instructions
-terminated by a jump or by a virtual CPU state change which the
-translator cannot deduce statically).
-
-@section Direct block chaining
-
-After each translated basic block is executed, QEMU uses the simulated
-Program Counter (PC) and other cpu state informations (such as the CS
-segment base value) to find the next basic block.
-
-In order to accelerate the most common cases where the new simulated PC
-is known, QEMU can patch a basic block so that it jumps directly to the
-next one.
-
-The most portable code uses an indirect jump. An indirect jump makes it
-easier to make the jump target modification atomic. On some
-architectures (such as PowerPC), the @code{JUMP} opcode is directly
-patched so that the block chaining has no overhead.
-
-@section Self-modifying code and translated code invalidation
+@section Target OS specific information
+
+@subsection Linux
+
+To have access to SVGA graphic modes under X11, use the @code{vesa} or
+the @code{cirrus} X11 driver. For optimal performances, use 16 bit
+color depth in the guest and the host OS.
+
+When using a 2.6 guest Linux kernel, you should add the option
+@code{clock=pit} on the kernel command line because the 2.6 Linux
+kernels make very strict real time clock checks by default that QEMU
+cannot simulate exactly.
+
+When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
+not activated because QEMU is slower with this patch. The QEMU
+Accelerator Module is also much slower in this case. Earlier Fedora
+Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporte this
+patch by default. Newer kernels don't have it.
+
+@subsection Windows
+
+If you have a slow host, using Windows 95 is better as it gives the
+best speed. Windows 2000 is also a good choice.
+
+@subsubsection SVGA graphic modes support
+
+QEMU emulates a Cirrus Logic GD5446 Video
+card. All Windows versions starting from Windows 95 should recognize
+and use this graphic card. For optimal performances, use 16 bit color
+depth in the guest and the host OS.
+
+@subsubsection CPU usage reduction
+
+Windows 9x does not correctly use the CPU HLT
+instruction. The result is that it takes host CPU cycles even when
+idle. You can install the utility from
+@url{http://www.user.cityline.ru/~maxamn/amnhltm.zip} to solve this
+problem. Note that no such tool is needed for NT, 2000 or XP.
+
+@subsubsection Windows 2000 disk full problem
+
+Windows 2000 has a bug which gives a disk full problem during its
+installation. When installing it, use the @option{-win2k-hack} QEMU
+option to enable a specific workaround. After Windows 2000 is
+installed, you no longer need this option (this option slows down the
+IDE transfers).
+
+@subsubsection Windows 2000 shutdown
+
+Windows 2000 cannot automatically shutdown in QEMU although Windows 98
+can. It comes from the fact that Windows 2000 does not automatically
+use the APM driver provided by the BIOS.
+
+In order to correct that, do the following (thanks to Struan
+Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
+Add/Troubleshoot a device => Add a new device & Next => No, select the
+hardware from a list & Next => NT Apm/Legacy Support & Next => Next
+(again) a few times. Now the driver is installed and Windows 2000 now
+correctly instructs QEMU to shutdown at the appropriate moment.
+
+@subsubsection Share a directory between Unix and Windows
+
+See @ref{sec_invocation} about the help of the option @option{-smb}.
+
+@subsubsection Windows XP security problems
+
+Some releases of Windows XP install correctly but give a security
+error when booting:
+@example
+A problem is preventing Windows from accurately checking the
+license for this computer. Error code: 0x800703e6.
+@end example
+The only known workaround is to boot in Safe mode
+without networking support.
+
+Future QEMU releases are likely to correct this bug.
+
+@subsection MS-DOS and FreeDOS
+
+@subsubsection CPU usage reduction
+
+DOS does not correctly use the CPU HLT instruction. The result is that
+it takes host CPU cycles even when idle. You can install the utility
+from @url{http://www.vmware.com/software/dosidle210.zip} to solve this
+problem.
+
+@chapter QEMU PowerPC System emulator invocation
+
+Use the executable @file{qemu-system-ppc} to simulate a complete PREP
+or PowerMac PowerPC system.
+
+QEMU emulates the following PowerMac peripherals:
+
+@itemize @minus
+@item
+UniNorth PCI Bridge
+@item
+PCI VGA compatible card with VESA Bochs Extensions
+@item
+2 PMAC IDE interfaces with hard disk and CD-ROM support
+@item
+NE2000 PCI adapters
+@item
+Non Volatile RAM
+@item
+VIA-CUDA with ADB keyboard and mouse.
+@end itemize
+
+QEMU emulates the following PREP peripherals:
+
+@itemize @minus
+@item
+PCI Bridge
+@item
+PCI VGA compatible card with VESA Bochs Extensions
+@item
+2 IDE interfaces with hard disk and CD-ROM support
+@item
+Floppy disk
+@item
+NE2000 network adapters
+@item
+Serial port
+@item
+PREP Non Volatile RAM
+@item
+PC compatible keyboard and mouse.
+@end itemize
+
+QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS available at
+@url{http://site.voila.fr/jmayer/OpenHackWare/index.htm}.
+
+You can read the qemu PC system emulation chapter to have more
+informations about QEMU usage.
+
+@c man begin OPTIONS
+
+The following options are specific to the PowerPC emulation:
+
+@table @option
+
+@item -g WxH[xDEPTH]
+
+Set the initial VGA graphic mode. The default is 800x600x15.
+
+@end table
+
+@c man end
+
+
+More information is available at
+@url{http://jocelyn.mayer.free.fr/qemu-ppc/}.
+
+@chapter Sparc32 System emulator invocation
+
+Use the executable @file{qemu-system-sparc} to simulate a JavaStation
+(sun4m architecture). The emulation is somewhat complete.
-Self-modifying code is a special challenge in x86 emulation because no
-instruction cache invalidation is signaled by the application when code
-is modified.
+QEMU emulates the following sun4m peripherals:
-When translated code is generated for a basic block, the corresponding
-host page is write protected if it is not already read-only (with the
-system call @code{mprotect()}). Then, if a write access is done to the
-page, Linux raises a SEGV signal. QEMU then invalidates all the
-translated code in the page and enables write accesses to the page.
+@itemize @minus
+@item
+IOMMU
+@item
+TCX Frame buffer
+@item
+Lance (Am7990) Ethernet
+@item
+Non Volatile RAM M48T08
+@item
+Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
+and power/reset logic
+@item
+ESP SCSI controller with hard disk and CD-ROM support
+@item
+Floppy drive
+@end itemize
+
+The number of peripherals is fixed in the architecture.
+
+QEMU uses the Proll, a PROM replacement available at
+@url{http://people.redhat.com/zaitcev/linux/}. The required
+QEMU-specific patches are included with the sources.
+
+A sample Linux 2.6 series kernel and ram disk image are available on
+the QEMU web site. Please note that currently neither Linux 2.4
+series, NetBSD, nor OpenBSD kernels work.
+
+@c man begin OPTIONS
+
+The following options are specific to the Sparc emulation:
+
+@table @option
+
+@item -g WxH
+
+Set the initial TCX graphic mode. The default is 1024x768.
+
+@end table
+
+@c man end
-Correct translated code invalidation is done efficiently by maintaining
-a linked list of every translated block contained in a given page. Other
-linked lists are also maintained to undo direct block chaining.
+@chapter Sparc64 System emulator invocation
-Although the overhead of doing @code{mprotect()} calls is important,
-most MSDOS programs can be emulated at reasonnable speed with QEMU and
-DOSEMU.
+Use the executable @file{qemu-system-sparc64} to simulate a Sun4u machine.
+The emulator is not usable for anything yet.
-Note that QEMU also invalidates pages of translated code when it detects
-that memory mappings are modified with @code{mmap()} or @code{munmap()}.
+QEMU emulates the following sun4u peripherals:
-@section Exception support
+@itemize @minus
+@item
+UltraSparc IIi APB PCI Bridge
+@item
+PCI VGA compatible card with VESA Bochs Extensions
+@item
+Non Volatile RAM M48T59
+@item
+PC-compatible serial ports
+@end itemize
-longjmp() is used when an exception such as division by zero is
-encountered.
+@chapter MIPS System emulator invocation
-The host SIGSEGV and SIGBUS signal handlers are used to get invalid
-memory accesses. The exact CPU state can be retrieved because all the
-x86 registers are stored in fixed host registers. The simulated program
-counter is found by retranslating the corresponding basic block and by
-looking where the host program counter was at the exception point.
+Use the executable @file{qemu-system-mips} to simulate a MIPS machine.
+The emulator begins to launch a Linux kernel.
-The virtual CPU cannot retrieve the exact @code{EFLAGS} register because
-in some cases it is not computed because of condition code
-optimisations. It is not a big concern because the emulated code can
-still be restarted in any cases.
+@chapter QEMU User space emulator invocation
-@section Linux system call translation
+@section Quick Start
-QEMU includes a generic system call translator for Linux. It means that
-the parameters of the system calls can be converted to fix the
-endianness and 32/64 bit issues. The IOCTLs are converted with a generic
-type description system (see @file{ioctls.h} and @file{thunk.c}).
+In order to launch a Linux process, QEMU needs the process executable
+itself and all the target (x86) dynamic libraries used by it.
-QEMU supports host CPUs which have pages bigger than 4KB. It records all
-the mappings the process does and try to emulated the @code{mmap()}
-system calls in cases where the host @code{mmap()} call would fail
-because of bad page alignment.
+@itemize
-@section Linux signals
+@item On x86, you can just try to launch any process by using the native
+libraries:
-Normal and real-time signals are queued along with their information
-(@code{siginfo_t}) as it is done in the Linux kernel. Then an interrupt
-request is done to the virtual CPU. When it is interrupted, one queued
-signal is handled by generating a stack frame in the virtual CPU as the
-Linux kernel does. The @code{sigreturn()} system call is emulated to return
-from the virtual signal handler.
+@example
+qemu-i386 -L / /bin/ls
+@end example
-Some signals (such as SIGALRM) directly come from the host. Other
-signals are synthetized from the virtual CPU exceptions such as SIGFPE
-when a division by zero is done (see @code{main.c:cpu_loop()}).
+@code{-L /} tells that the x86 dynamic linker must be searched with a
+@file{/} prefix.
-The blocked signal mask is still handled by the host Linux kernel so
-that most signal system calls can be redirected directly to the host
-Linux kernel. Only the @code{sigaction()} and @code{sigreturn()} system
-calls need to be fully emulated (see @file{signal.c}).
+@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):
-@section clone() system call and threads
+@example
+qemu-i386 -L / qemu-i386 -L / /bin/ls
+@end example
-The Linux clone() system call is usually used to create a thread. QEMU
-uses the host clone() system call so that real host threads are created
-for each emulated thread. One virtual CPU instance is created for each
-thread.
+@item On non x86 CPUs, you need first to download at least an x86 glibc
+(@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
+@code{LD_LIBRARY_PATH} is not set:
-The virtual x86 CPU atomic operations are emulated with a global lock so
-that their semantic is preserved.
+@example
+unset LD_LIBRARY_PATH
+@end example
-Note that currently there are still some locking issues in QEMU. In
-particular, the translated cache flush is not protected yet against
-reentrancy.
+Then you can launch the precompiled @file{ls} x86 executable:
-@section Self-virtualization
+@example
+qemu-i386 tests/i386/ls
+@end example
+You can look at @file{qemu-binfmt-conf.sh} so that
+QEMU is automatically launched by the Linux kernel when you try to
+launch x86 executables. It requires the @code{binfmt_misc} module in the
+Linux kernel.
-QEMU was conceived so that ultimately it can emulate itself. Although
-it is not very useful, it is an important test to show the power of the
-emulator.
+@item The x86 version of QEMU is also included. You can try weird things such as:
+@example
+qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 /usr/local/qemu-i386/bin/ls-i386
+@end example
-Achieving self-virtualization is not easy because there may be address
-space conflicts. QEMU solves this problem by being an executable ELF
-shared object as the ld-linux.so ELF interpreter. That way, it can be
-relocated at load time.
+@end itemize
-@section MMU emulation
+@section Wine launch
-For system emulation, QEMU uses the mmap() system call to emulate the
-target CPU MMU. It works as long the emulated OS does not use an area
-reserved by the host OS (such as the area above 0xc0000000 on x86
-Linux).
+@itemize
-It is planned to add a slower but more precise MMU emulation
-with a software MMU.
+@item Ensure that you have a working QEMU with the x86 glibc
+distribution (see previous section). In order to verify it, you must be
+able to do:
-@section Bibliography
+@example
+qemu-i386 /usr/local/qemu-i386/bin/ls-i386
+@end example
-@table @asis
+@item Download the binary x86 Wine install
+(@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
-@item [1]
-@url{http://citeseer.nj.nec.com/piumarta98optimizing.html}, Optimizing
-direct threaded code by selective inlining (1998) by Ian Piumarta, Fabio
-Riccardi.
+@item Configure Wine on your account. Look at the provided script
+@file{/usr/local/qemu-i386/bin/wine-conf.sh}. Your previous
+@code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
-@item [2]
-@url{http://developer.kde.org/~sewardj/}, Valgrind, an open-source
-memory debugger for x86-GNU/Linux, by Julian Seward.
+@item Then you can try the example @file{putty.exe}:
-@item [3]
-@url{http://bochs.sourceforge.net/}, the Bochs IA-32 Emulator Project,
-by Kevin Lawton et al.
+@example
+qemu-i386 /usr/local/qemu-i386/wine/bin/wine /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
+@end example
-@item [4]
-@url{http://www.cs.rose-hulman.edu/~donaldlf/em86/index.html}, the EM86
-x86 emulator on Alpha-Linux.
+@end itemize
-@item [5]
-@url{http://www.usenix.org/publications/library/proceedings/usenix-nt97/full_papers/chernoff/chernoff.pdf},
-DIGITAL FX!32: Running 32-Bit x86 Applications on Alpha NT, by Anton
-Chernoff and Ray Hookway.
+@section Command line options
-@item [6]
-@url{http://www.willows.com/}, Windows API library emulation from
-Willows Software.
+@example
+usage: qemu-i386 [-h] [-d] [-L path] [-s size] program [arguments...]
+@end example
-@item [7]
-@url{http://user-mode-linux.sourceforge.net/},
-The User-mode Linux Kernel.
+@table @option
+@item -h
+Print the help
+@item -L path
+Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
+@item -s size
+Set the x86 stack size in bytes (default=524288)
+@end table
-@item [8]
-@url{http://www.plex86.org/},
-The new Plex86 project.
+Debug options:
+@table @option
+@item -d
+Activate log (logfile=/tmp/qemu.log)
+@item -p pagesize
+Act as if the host page size was 'pagesize' bytes
@end table
-@chapter Regression Tests
+@node compilation
+@chapter Compilation from the sources
+
+@section Linux/Unix
+
+@subsection Compilation
+
+First you must decompress the sources:
+@example
+cd /tmp
+tar zxvf qemu-x.y.z.tar.gz
+cd qemu-x.y.z
+@end example
+
+Then you configure QEMU and build it (usually no options are needed):
+@example
+./configure
+make
+@end example
+
+Then type as root user:
+@example
+make install
+@end example
+to install QEMU in @file{/usr/local}.
+
+@subsection Tested tool versions
+
+In order to compile QEMU succesfully, it is very important that you
+have the right tools. The most important one is gcc. I cannot guaranty
+that QEMU works if you do not use a tested gcc version. Look at
+'configure' and 'Makefile' if you want to make a different gcc
+version work.
-In the directory @file{tests/}, various interesting testing programs
-are available. There are used for regression testing.
+@example
+host gcc binutils glibc linux distribution
+----------------------------------------------------------------------
+x86 3.2 2.13.2 2.1.3 2.4.18
+ 2.96 2.11.93.0.2 2.2.5 2.4.18 Red Hat 7.3
+ 3.2.2 2.13.90.0.18 2.3.2 2.4.20 Red Hat 9
+
+PowerPC 3.3 [4] 2.13.90.0.18 2.3.1 2.4.20briq
+ 3.2
+
+Alpha 3.3 [1] 2.14.90.0.4 2.2.5 2.2.20 [2] Debian 3.0
+
+Sparc32 2.95.4 2.12.90.0.1 2.2.5 2.4.18 Debian 3.0
-@section @file{test-i386}
+ARM 2.95.4 2.12.90.0.1 2.2.5 2.4.9 [3] Debian 3.0
-This program executes most of the 16 bit and 32 bit x86 instructions and
-generates a text output. It can be compared with the output obtained with
-a real CPU or another emulator. The target @code{make test} runs this
-program and a @code{diff} on the generated output.
+[1] On Alpha, QEMU needs the gcc 'visibility' attribute only available
+ for gcc version >= 3.3.
+[2] Linux >= 2.4.20 is necessary for precise exception support
+ (untested).
+[3] 2.4.9-ac10-rmk2-np1-cerf2
-The Linux system call @code{modify_ldt()} is used to create x86 selectors
-to test some 16 bit addressing and 32 bit with segmentation cases.
+[4] gcc 2.95.x generates invalid code when using too many register
+variables. You must use gcc 3.x on PowerPC.
+@end example
+
+@section Windows
+
+@itemize
+@item Install the current versions of MSYS and MinGW from
+@url{http://www.mingw.org/}. You can find detailed installation
+instructions in the download section and the FAQ.
+
+@item Download
+the MinGW development library of SDL 1.2.x
+(@file{SDL-devel-1.2.x-mingw32.tar.gz}) from
+@url{http://www.libsdl.org}. Unpack it in a temporary place, and
+unpack the archive @file{i386-mingw32msvc.tar.gz} in the MinGW tool
+directory. Edit the @file{sdl-config} script so that it gives the
+correct SDL directory when invoked.
+
+@item Extract the current version of QEMU.
+
+@item Start the MSYS shell (file @file{msys.bat}).
+
+@item Change to the QEMU directory. Launch @file{./configure} and
+@file{make}. If you have problems using SDL, verify that
+@file{sdl-config} can be launched from the MSYS command line.
+
+@item You can install QEMU in @file{Program Files/Qemu} by typing
+@file{make install}. Don't forget to copy @file{SDL.dll} in
+@file{Program Files/Qemu}.
-The Linux system call @code{vm86()} is used to test vm86 emulation.
+@end itemize
-Various exceptions are raised to test most of the x86 user space
-exception reporting.
+@section Cross compilation for Windows with Linux
-@section @file{linux-test}
+@itemize
+@item
+Install the MinGW cross compilation tools available at
+@url{http://www.mingw.org/}.
-This program tests various Linux system calls. It is used to verify
-that the system call parameters are correctly converted between target
-and host CPUs.
+@item
+Install the Win32 version of SDL (@url{http://www.libsdl.org}) by
+unpacking @file{i386-mingw32msvc.tar.gz}. Set up the PATH environment
+variable so that @file{i386-mingw32msvc-sdl-config} can be launched by
+the QEMU configuration script.
-@section @file{hello-i386}
+@item
+Configure QEMU for Windows cross compilation:
+@example
+./configure --enable-mingw32
+@end example
+If necessary, you can change the cross-prefix according to the prefix
+choosen for the MinGW tools with --cross-prefix. You can also use
+--prefix to set the Win32 install path.
-Very simple statically linked x86 program, just to test QEMU during a
-port to a new host CPU.
+@item You can install QEMU in the installation directory by typing
+@file{make install}. Don't forget to copy @file{SDL.dll} in the
+installation directory.
-@section @file{hello-arm}
+@end itemize
-Very simple statically linked ARM program, just to test QEMU during a
-port to a new host CPU.
+Note: Currently, Wine does not seem able to launch
+QEMU for Win32.
-@section @file{sha1}
+@section Mac OS X
-It is a simple benchmark. Care must be taken to interpret the results
-because it mostly tests the ability of the virtual CPU to optimize the
-@code{rol} x86 instruction and the condition code computations.
+The Mac OS X patches are not fully merged in QEMU, so you should look
+at the QEMU mailing list archive to have all the necessary
+information.
projects / qemu / blobdiff