\input texinfo @c -*- texinfo -*- @iftex @settitle QEMU CPU Emulator User Documentation @titlepage @sp 7 @center @titlefont{QEMU CPU Emulator User Documentation} @sp 3 @end titlepage @end iftex @chapter Introduction @section Features QEMU is a FAST! processor emulator using dynamic translation to achieve good emulation speed. QEMU has two operating modes: @itemize @minus @item Full system emulation. In this mode, QEMU emulates a full system (for example a PC), including one or several processors and various peripherals. It can be used to launch different Operating Systems without rebooting the PC or to debug system code. @item 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 QEMU can run without an host kernel driver and yet gives acceptable performance. For system emulation, the following hardware targets are supported: @itemize @item PC (x86 or x86_64 processor) @item ISA PC (old style PC without PCI bus) @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) @item ARM Integrator/CP (ARM926E or 1026E processor) @end itemize For user emulation, x86, PowerPC, ARM, MIPS, and Sparc32/64 CPUs are supported. @chapter Installation If you want to compile QEMU yourself, see @ref{compilation}. @section Linux If a precompiled package is available for your distribution - you just have to install it. Otherwise, see @ref{compilation}. @section Windows Download the experimental binary installer at @url{http://www.free.oszoo.org/download.html}. @section Mac OS X Download the experimental binary installer at @url{http://www.free.oszoo.org/download.html}. @chapter QEMU PC System emulator @section Introduction @c man begin DESCRIPTION The QEMU PC System emulator simulates the following peripherals: @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 SMP is supported with up to 255 CPUs. Note that adlib is only available when QEMU was configured with -enable-adlib QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL VGA BIOS. QEMU uses YM3812 emulation by Tatsuyuki Satoh. @c man end @section Quick Start Download and uncompress the linux image (@file{linux.img}) and type: @example qemu linux.img @end example Linux should boot and give you a prompt. @node sec_invocation @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 disk image for IDE hard disk 0. General options: @table @option @item -M machine Select the emulated machine (@code{-M ?} for list) @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 -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 -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 -boot [a|c|d] Boot on floppy (a), hard disk (c) or CD-ROM (d). Hard disk boot is the default. @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. Default is 128 MB. @item -smp n Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 CPUs are supported. @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. @item -k language 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. 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 The default is @code{en-us}. @item -audio-help Will show the audio subsystem help: list of drivers, tunable parameters. @item -soundhw card1,card2,... or -soundhw all Enable audio and selected sound hardware. Use ? to print all available sound hardware. @example qemu -soundhw sb16,adlib hda qemu -soundhw es1370 hda qemu -soundhw all hda qemu -soundhw ? @end example @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. @item -full-screen Start in full screen. @item -pidfile file Store the QEMU process PID in @var{file}. It is useful if you launch QEMU from a script. @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). @end table USB options: @table @option @item -usb Enable the USB driver (will be the default soon) @item -usbdevice devname Add the USB device @var{devname}. See the monitor command @code{usb_add} to have more information. @end table Network options: @table @option @item -net nic[,vlan=n][,macaddr=addr][,model=type] 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. Qemu can emulate several different models of network card. Valid values for @var{type} are @code{ne2k_pci}, @code{ne2k_isa}, @code{rtl8139}, @code{smc91c111} and @code{lance}. Not all devices are supported on all targets. @item -net user[,vlan=n][,hostname=name] Use the user mode network stack which requires no administrator priviledge to run. @option{hostname=name} can be used to specify the client hostname reported by the builtin DHCP server. @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 linux.img -net nic -net tap @end example More complicated example (two NICs, each one connected to a TAP device) @example 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 @item -net socket[,vlan=n][,fd=h][,listen=[host]:port][,connect=host:port] 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 TCP socket. 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 socket[,vlan=n][,fd=h][,mcast=maddr:port] Create a VLAN @var{n} shared with another QEMU virtual machines using a UDP multicast socket, effectively making a bus for every QEMU with same multicast address @var{maddr} and @var{port}. NOTES: @enumerate @item Several QEMU can be running on different hosts and share same bus (assuming correct multicast setup for these hosts). @item mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see @url{http://user-mode-linux.sf.net}. @item Use @option{fd=h} to specify an already opened UDP multicast socket. @end enumerate Example: @example # launch one QEMU instance qemu linux.img -net nic,macaddr=52:54:00:12:34:56 -net socket,mcast=230.0.0.1:1234 # launch another QEMU instance on same "bus" qemu linux.img -net nic,macaddr=52:54:00:12:34:57 -net socket,mcast=230.0.0.1:1234 # launch yet another QEMU instance on same "bus" qemu linux.img -net nic,macaddr=52:54:00:12:34:58 -net socket,mcast=230.0.0.1:1234 @end example Example (User Mode Linux compat.): @example # launch QEMU instance (note mcast address selected is UML's default) qemu linux.img -net nic,macaddr=52:54:00:12:34:56 -net socket,mcast=239.192.168.1:1102 # launch UML /path/to/linux ubd0=/path/to/root_fs eth0=mcast @end example @item -net none Indicate that no network devices should be configured. It is used to override the default configuration (@option{-net nic -net user}) 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 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). Then @file{dir} can be accessed in @file{\\smbserver\qemu}. 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 -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 # on the host qemu -redir tcp:6001::6000 [...] # this host xterm should open in the guest X11 server xterm -display :1 @end example To redirect telnet connections from host port 5555 to telnet port on the guest, use the following: @example # on the host qemu -redir tcp:5555::23 [...] telnet localhost 5555 @end example Then when you use on the host @code{telnet localhost 5555}, you connect to the guest telnet server. @end table 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 -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/Expert options: @table @option @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. This option can be used several times to simulate up to 4 serials ports. @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. This option can be used several times to simulate up to 3 parallel ports. @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 -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 @c man end @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 @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 Remove or insert removable medias images (such as CD-ROM or floppies) @item 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 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 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 @item p or print/fmt expr Print expression value. Only the @var{format} part of @var{fmt} is used. @item sendkey keys Send @var{keys} to the emulator. Use @code{-} to press several keys simultaneously. Example: @example sendkey ctrl-alt-f1 @end example 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 @subsection Virtual FAT disk images QEMU can automatically create a virtual FAT disk image from a directory tree. In order to use it, just type: @example qemu linux.img -hdb fat:/my_directory @end example Then you access access to all the files in the @file{/my_directory} directory without having to copy them in a disk image or to export them via SAMBA or NFS. The default access is @emph{read-only}. Floppies can be emulated with the @code{:floppy:} option: @example qemu linux.img -fda fat:floppy:/my_directory @end example A read/write support is available for testing (beta stage) with the @code{:rw:} option: @example qemu linux.img -fda fat:floppy:rw:/my_directory @end example What you should @emph{never} do: @itemize @item use non-ASCII filenames ; @item use "-snapshot" together with ":rw:" ; @item expect it to work when loadvm'ing ; @item write to the FAT directory on the host system while accessing it with the guest system. @end itemize @section 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 kernel testing. The QEMU network configuration is also explained. @enumerate @item Download the archive @file{linux-test-xxx.tar.gz} containing a Linux kernel and a disk image. @item Optional: If you want network support (for example to launch X11 examples), you must 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 TUN/TAP network interfaces: the device @file{/dev/net/tun} must be present. When network is enabled, there is a virtual network connection between the host kernel and the emulated kernel. The emulated kernel is seen from the host kernel at IP address 172.20.0.2 and the host kernel is seen from the emulated kernel at IP address 172.20.0.1. @item Launch @code{qemu.sh}. You should have the following output: @example > ./qemu.sh 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) 32MB LOWMEM available. On node 0 totalpages: 8192 zone(0): 4096 pages. zone(1): 4096 pages. zone(2): 0 pages. 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 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) 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 Checking 'hlt' instruction... OK. POSIX conformance testing by UNIFIX Linux NET4.0 for Linux 2.4 Based upon Swansea University Computer Society NET3.039 Initializing RT netlink socket 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 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 TCP: Hash tables configured (established 2048 bind 4096) 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: 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 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 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 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). @subsection Using virtual USB devices A virtual USB mouse device is available for testing in QEMU. You can try it with the following monitor commands: @example # add the mouse device (qemu) usb_add mouse # show the virtual USB devices plugged on the QEMU Virtual USB hub (qemu) info usb Device 0.3, speed 12 Mb/s # after some time you can try to remove the mouse (qemu) usb_del 0.3 @end example The option @option{-usbdevice} is similar to the monitor command @code{usb_add}. @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 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}. @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that: @example ls /proc/bus/usb 001 devices drivers @end example @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 chown -R myuid /proc/bus/usb @end example @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 You should see the list of the devices you can use (Never try to use hubs, it won't work). @item Add the device in QEMU by using: @example usb_add host:1234:5678 @end example Normally the guest OS should report that a new USB device is plugged. You can use the option @option{-usbdevice} to do the same. @item Now you can try to use the host USB device in QEMU. @end enumerate 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 qemu with the '-s' option. It will wait for a gdb connection: @example > 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 Then launch gdb on the 'vmlinux' executable: @example > gdb vmlinux @end example In gdb, connect to QEMU: @example (gdb) target remote localhost:1234 @end example Then you can use gdb normally. For example, type 'c' to launch the kernel: @example (gdb) c @end example Here are some useful tips in order to use gdb on system code: @enumerate @item Use @code{info reg} to display all the CPU registers. @item Use @code{x/10i $eip} to display the code at the PC position. @item Use @code{set architecture i8086} to dump 16 bit code. Then use @code{x/10i $cs*16+*eip} to dump the code at the PC position. @end enumerate @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 System emulator for non PC targets QEMU is a generic emulator and it emulates many non PC machines. Most of the options are similar to the PC emulator. The differences are mentionned in the following sections. @section QEMU PowerPC System emulator 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://perso.magic.fr/l_indien/OpenHackWare/index.htm}. @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://perso.magic.fr/l_indien/qemu-ppc/}. @section Sparc32 System emulator invocation Use the executable @file{qemu-system-sparc} to simulate a JavaStation (sun4m architecture). The emulation is somewhat complete. QEMU emulates the following sun4m peripherals: @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 @section Sparc64 System emulator invocation Use the executable @file{qemu-system-sparc64} to simulate a Sun4u machine. The emulator is not usable for anything yet. QEMU emulates the following sun4u peripherals: @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 @section MIPS System emulator invocation Use the executable @file{qemu-system-mips} to simulate a MIPS machine. The emulator is able to boot a Linux kernel and to run a Linux Debian installation from NFS. The following devices are emulated: @itemize @minus @item MIPS R4K CPU @item PC style serial port @item NE2000 network card @end itemize More information is available in the QEMU mailing-list archive. @section ARM System emulator invocation Use the executable @file{qemu-system-arm} to simulate a ARM machine. The ARM Integrator/CP board is emulated with the following devices: @itemize @minus @item ARM926E or ARM1026E CPU @item Two PL011 UARTs @item SMC 91c111 Ethernet adapter @end itemize A Linux 2.6 test image is available on the QEMU web site. More information is available in the QEMU mailing-list archive. @chapter QEMU Linux User space emulator @section Quick Start In order to launch a Linux process, QEMU needs the process executable itself and all the target (x86) dynamic libraries used by it. @itemize @item On x86, you can just try to launch any process by using the native libraries: @example qemu-i386 -L / /bin/ls @end example @code{-L /} tells that the x86 dynamic linker must be searched with a @file{/} prefix. @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): @example qemu-i386 -L / qemu-i386 -L / /bin/ls @end example @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: @example unset LD_LIBRARY_PATH @end example Then you can launch the precompiled @file{ls} x86 executable: @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. @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 @end itemize @section Wine launch @itemize @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 qemu-i386 /usr/local/qemu-i386/bin/ls-i386 @end example @item Download the binary x86 Wine install (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page). @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 Then you can try the example @file{putty.exe}: @example qemu-i386 /usr/local/qemu-i386/wine/bin/wine /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe @end example @end itemize @section Command line options @example usage: qemu-i386 [-h] [-d] [-L path] [-s size] program [arguments...] @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) @end table 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 @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. @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 ARM 2.95.4 2.12.90.0.1 2.2.5 2.4.9 [3] Debian 3.0 [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 [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}. @end itemize @section Cross compilation for Windows with Linux @itemize @item Install the MinGW cross compilation tools available at @url{http://www.mingw.org/}. @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. @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. @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. @end itemize Note: Currently, Wine does not seem able to launch QEMU for Win32. @section Mac OS X 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.