1 \input texinfo @c -*- texinfo -*-
3 @setfilename qemu-doc.info
6 @documentencoding UTF-8
8 @settitle QEMU Emulator User Documentation
15 * QEMU: (qemu-doc). The QEMU Emulator User Documentation.
22 @center @titlefont{QEMU Emulator}
24 @center @titlefont{User Documentation}
36 * QEMU PC System emulator::
37 * QEMU System emulator for non PC targets::
38 * QEMU User space emulator::
39 * compilation:: Compilation from the sources
51 * intro_features:: Features
57 QEMU is a FAST! processor emulator using dynamic translation to
58 achieve good emulation speed.
60 QEMU has two operating modes:
63 @cindex operating modes
66 @cindex system emulation
67 Full system emulation. In this mode, QEMU emulates a full system (for
68 example a PC), including one or several processors and various
69 peripherals. It can be used to launch different Operating Systems
70 without rebooting the PC or to debug system code.
73 @cindex user mode emulation
74 User mode emulation. In this mode, QEMU can launch
75 processes compiled for one CPU on another CPU. It can be used to
76 launch the Wine Windows API emulator (@url{http://www.winehq.org}) or
77 to ease cross-compilation and cross-debugging.
81 QEMU can run without a host kernel driver and yet gives acceptable
84 For system emulation, the following hardware targets are supported:
86 @cindex emulated target systems
87 @cindex supported target systems
88 @item PC (x86 or x86_64 processor)
89 @item ISA PC (old style PC without PCI bus)
90 @item PREP (PowerPC processor)
91 @item G3 Beige PowerMac (PowerPC processor)
92 @item Mac99 PowerMac (PowerPC processor, in progress)
93 @item Sun4m/Sun4c/Sun4d (32-bit Sparc processor)
94 @item Sun4u/Sun4v (64-bit Sparc processor, in progress)
95 @item Malta board (32-bit and 64-bit MIPS processors)
96 @item MIPS Magnum (64-bit MIPS processor)
97 @item ARM Integrator/CP (ARM)
98 @item ARM Versatile baseboard (ARM)
99 @item ARM RealView Emulation/Platform baseboard (ARM)
100 @item Spitz, Akita, Borzoi, Terrier and Tosa PDAs (PXA270 processor)
101 @item Luminary Micro LM3S811EVB (ARM Cortex-M3)
102 @item Luminary Micro LM3S6965EVB (ARM Cortex-M3)
103 @item Freescale MCF5208EVB (ColdFire V2).
104 @item Arnewsh MCF5206 evaluation board (ColdFire V2).
105 @item Palm Tungsten|E PDA (OMAP310 processor)
106 @item N800 and N810 tablets (OMAP2420 processor)
107 @item MusicPal (MV88W8618 ARM processor)
108 @item Gumstix "Connex" and "Verdex" motherboards (PXA255/270).
109 @item Siemens SX1 smartphone (OMAP310 processor)
110 @item AXIS-Devboard88 (CRISv32 ETRAX-FS).
111 @item Petalogix Spartan 3aDSP1800 MMU ref design (MicroBlaze).
112 @item Avnet LX60/LX110/LX200 boards (Xtensa)
115 @cindex supported user mode targets
116 For user emulation, x86 (32 and 64 bit), PowerPC (32 and 64 bit),
117 ARM, MIPS (32 bit only), Sparc (32 and 64 bit),
118 Alpha, ColdFire(m68k), CRISv32 and MicroBlaze CPUs are supported.
121 @chapter Installation
123 If you want to compile QEMU yourself, see @ref{compilation}.
126 * install_linux:: Linux
127 * install_windows:: Windows
128 * install_mac:: Macintosh
133 @cindex installation (Linux)
135 If a precompiled package is available for your distribution - you just
136 have to install it. Otherwise, see @ref{compilation}.
138 @node install_windows
140 @cindex installation (Windows)
142 Download the experimental binary installer at
143 @url{http://www.free.oszoo.org/@/download.html}.
144 TODO (no longer available)
149 Download the experimental binary installer at
150 @url{http://www.free.oszoo.org/@/download.html}.
151 TODO (no longer available)
153 @node QEMU PC System emulator
154 @chapter QEMU PC System emulator
155 @cindex system emulation (PC)
158 * pcsys_introduction:: Introduction
159 * pcsys_quickstart:: Quick Start
160 * sec_invocation:: Invocation
162 * pcsys_monitor:: QEMU Monitor
163 * disk_images:: Disk Images
164 * pcsys_network:: Network emulation
165 * pcsys_other_devs:: Other Devices
166 * direct_linux_boot:: Direct Linux Boot
167 * pcsys_usb:: USB emulation
168 * vnc_security:: VNC security
169 * gdb_usage:: GDB usage
170 * pcsys_os_specific:: Target OS specific information
173 @node pcsys_introduction
174 @section Introduction
176 @c man begin DESCRIPTION
178 The QEMU PC System emulator simulates the
179 following peripherals:
183 i440FX host PCI bridge and PIIX3 PCI to ISA bridge
185 Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
186 extensions (hardware level, including all non standard modes).
188 PS/2 mouse and keyboard
190 2 PCI IDE interfaces with hard disk and CD-ROM support
194 PCI and ISA network adapters
198 Creative SoundBlaster 16 sound card
200 ENSONIQ AudioPCI ES1370 sound card
202 Intel 82801AA AC97 Audio compatible sound card
204 Intel HD Audio Controller and HDA codec
206 Adlib (OPL2) - Yamaha YM3812 compatible chip
208 Gravis Ultrasound GF1 sound card
210 CS4231A compatible sound card
212 PCI UHCI USB controller and a virtual USB hub.
215 SMP is supported with up to 255 CPUs.
217 Note that adlib, gus and cs4231a are only available when QEMU was
218 configured with --audio-card-list option containing the name(s) of
221 QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
224 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
226 QEMU uses GUS emulation (GUSEMU32 @url{http://www.deinmeister.de/gusemu/})
227 by Tibor "TS" Schütz.
229 Note that, by default, GUS shares IRQ(7) with parallel ports and so
230 QEMU must be told to not have parallel ports to have working GUS.
233 qemu-system-i386 dos.img -soundhw gus -parallel none
238 qemu-system-i386 dos.img -device gus,irq=5
241 Or some other unclaimed IRQ.
243 CS4231A is the chip used in Windows Sound System and GUSMAX products
247 @node pcsys_quickstart
251 Download and uncompress the linux image (@file{linux.img}) and type:
254 qemu-system-i386 linux.img
257 Linux should boot and give you a prompt.
263 @c man begin SYNOPSIS
264 usage: qemu-system-i386 [options] [@var{disk_image}]
269 @var{disk_image} is a raw hard disk image for IDE hard disk 0. Some
270 targets do not need a disk image.
272 @include qemu-options.texi
281 During the graphical emulation, you can use special key combinations to change
282 modes. The default key mappings are shown below, but if you use @code{-alt-grab}
283 then the modifier is Ctrl-Alt-Shift (instead of Ctrl-Alt) and if you use
284 @code{-ctrl-grab} then the modifier is the right Ctrl key (instead of Ctrl-Alt):
301 Restore the screen's un-scaled dimensions
305 Switch to virtual console 'n'. Standard console mappings are:
308 Target system display
317 Toggle mouse and keyboard grab.
323 @kindex Ctrl-PageDown
324 In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
325 @key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
328 During emulation, if you are using the @option{-nographic} option, use
329 @key{Ctrl-a h} to get terminal commands:
342 Save disk data back to file (if -snapshot)
345 Toggle console timestamps
348 Send break (magic sysrq in Linux)
351 Switch between console and monitor
361 The HTML documentation of QEMU for more precise information and Linux
362 user mode emulator invocation.
372 @section QEMU Monitor
375 The QEMU monitor is used to give complex commands to the QEMU
376 emulator. You can use it to:
381 Remove or insert removable media images
382 (such as CD-ROM or floppies).
385 Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
388 @item Inspect the VM state without an external debugger.
394 The following commands are available:
396 @include qemu-monitor.texi
398 @subsection Integer expressions
400 The monitor understands integers expressions for every integer
401 argument. You can use register names to get the value of specifics
402 CPU registers by prefixing them with @emph{$}.
407 Since version 0.6.1, QEMU supports many disk image formats, including
408 growable disk images (their size increase as non empty sectors are
409 written), compressed and encrypted disk images. Version 0.8.3 added
410 the new qcow2 disk image format which is essential to support VM
414 * disk_images_quickstart:: Quick start for disk image creation
415 * disk_images_snapshot_mode:: Snapshot mode
416 * vm_snapshots:: VM snapshots
417 * qemu_img_invocation:: qemu-img Invocation
418 * qemu_nbd_invocation:: qemu-nbd Invocation
419 * disk_images_formats:: Disk image file formats
420 * host_drives:: Using host drives
421 * disk_images_fat_images:: Virtual FAT disk images
422 * disk_images_nbd:: NBD access
423 * disk_images_sheepdog:: Sheepdog disk images
424 * disk_images_iscsi:: iSCSI LUNs
425 * disk_images_gluster:: GlusterFS disk images
426 * disk_images_ssh:: Secure Shell (ssh) disk images
429 @node disk_images_quickstart
430 @subsection Quick start for disk image creation
432 You can create a disk image with the command:
434 qemu-img create myimage.img mysize
436 where @var{myimage.img} is the disk image filename and @var{mysize} is its
437 size in kilobytes. You can add an @code{M} suffix to give the size in
438 megabytes and a @code{G} suffix for gigabytes.
440 See @ref{qemu_img_invocation} for more information.
442 @node disk_images_snapshot_mode
443 @subsection Snapshot mode
445 If you use the option @option{-snapshot}, all disk images are
446 considered as read only. When sectors in written, they are written in
447 a temporary file created in @file{/tmp}. You can however force the
448 write back to the raw disk images by using the @code{commit} monitor
449 command (or @key{C-a s} in the serial console).
452 @subsection VM snapshots
454 VM snapshots are snapshots of the complete virtual machine including
455 CPU state, RAM, device state and the content of all the writable
456 disks. In order to use VM snapshots, you must have at least one non
457 removable and writable block device using the @code{qcow2} disk image
458 format. Normally this device is the first virtual hard drive.
460 Use the monitor command @code{savevm} to create a new VM snapshot or
461 replace an existing one. A human readable name can be assigned to each
462 snapshot in addition to its numerical ID.
464 Use @code{loadvm} to restore a VM snapshot and @code{delvm} to remove
465 a VM snapshot. @code{info snapshots} lists the available snapshots
466 with their associated information:
469 (qemu) info snapshots
470 Snapshot devices: hda
471 Snapshot list (from hda):
472 ID TAG VM SIZE DATE VM CLOCK
473 1 start 41M 2006-08-06 12:38:02 00:00:14.954
474 2 40M 2006-08-06 12:43:29 00:00:18.633
475 3 msys 40M 2006-08-06 12:44:04 00:00:23.514
478 A VM snapshot is made of a VM state info (its size is shown in
479 @code{info snapshots}) and a snapshot of every writable disk image.
480 The VM state info is stored in the first @code{qcow2} non removable
481 and writable block device. The disk image snapshots are stored in
482 every disk image. The size of a snapshot in a disk image is difficult
483 to evaluate and is not shown by @code{info snapshots} because the
484 associated disk sectors are shared among all the snapshots to save
485 disk space (otherwise each snapshot would need a full copy of all the
488 When using the (unrelated) @code{-snapshot} option
489 (@ref{disk_images_snapshot_mode}), you can always make VM snapshots,
490 but they are deleted as soon as you exit QEMU.
492 VM snapshots currently have the following known limitations:
495 They cannot cope with removable devices if they are removed or
496 inserted after a snapshot is done.
498 A few device drivers still have incomplete snapshot support so their
499 state is not saved or restored properly (in particular USB).
502 @node qemu_img_invocation
503 @subsection @code{qemu-img} Invocation
505 @include qemu-img.texi
507 @node qemu_nbd_invocation
508 @subsection @code{qemu-nbd} Invocation
510 @include qemu-nbd.texi
512 @node disk_images_formats
513 @subsection Disk image file formats
515 QEMU supports many image file formats that can be used with VMs as well as with
516 any of the tools (like @code{qemu-img}). This includes the preferred formats
517 raw and qcow2 as well as formats that are supported for compatibility with
518 older QEMU versions or other hypervisors.
520 Depending on the image format, different options can be passed to
521 @code{qemu-img create} and @code{qemu-img convert} using the @code{-o} option.
522 This section describes each format and the options that are supported for it.
527 Raw disk image format. This format has the advantage of
528 being simple and easily exportable to all other emulators. If your
529 file system supports @emph{holes} (for example in ext2 or ext3 on
530 Linux or NTFS on Windows), then only the written sectors will reserve
531 space. Use @code{qemu-img info} to know the real size used by the
532 image or @code{ls -ls} on Unix/Linux.
535 QEMU image format, the most versatile format. Use it to have smaller
536 images (useful if your filesystem does not supports holes, for example
537 on Windows), optional AES encryption, zlib based compression and
538 support of multiple VM snapshots.
543 Determines the qcow2 version to use. @code{compat=0.10} uses the traditional
544 image format that can be read by any QEMU since 0.10 (this is the default).
545 @code{compat=1.1} enables image format extensions that only QEMU 1.1 and
546 newer understand. Amongst others, this includes zero clusters, which allow
547 efficient copy-on-read for sparse images.
550 File name of a base image (see @option{create} subcommand)
552 Image format of the base image
554 If this option is set to @code{on}, the image is encrypted.
556 Encryption uses the AES format which is very secure (128 bit keys). Use
557 a long password (16 characters) to get maximum protection.
560 Changes the qcow2 cluster size (must be between 512 and 2M). Smaller cluster
561 sizes can improve the image file size whereas larger cluster sizes generally
562 provide better performance.
565 Preallocation mode (allowed values: off, metadata). An image with preallocated
566 metadata is initially larger but can improve performance when the image needs
570 If this option is set to @code{on}, reference count updates are postponed with
571 the goal of avoiding metadata I/O and improving performance. This is
572 particularly interesting with @option{cache=writethrough} which doesn't batch
573 metadata updates. The tradeoff is that after a host crash, the reference count
574 tables must be rebuilt, i.e. on the next open an (automatic) @code{qemu-img
575 check -r all} is required, which may take some time.
577 This option can only be enabled if @code{compat=1.1} is specified.
582 Old QEMU image format with support for backing files and compact image files
583 (when your filesystem or transport medium does not support holes).
585 When converting QED images to qcow2, you might want to consider using the
586 @code{lazy_refcounts=on} option to get a more QED-like behaviour.
591 File name of a base image (see @option{create} subcommand).
593 Image file format of backing file (optional). Useful if the format cannot be
594 autodetected because it has no header, like some vhd/vpc files.
596 Changes the cluster size (must be power-of-2 between 4K and 64K). Smaller
597 cluster sizes can improve the image file size whereas larger cluster sizes
598 generally provide better performance.
600 Changes the number of clusters per L1/L2 table (must be power-of-2 between 1
601 and 16). There is normally no need to change this value but this option can be
602 used for performance benchmarking.
606 Old QEMU image format with support for backing files, compact image files,
607 encryption and compression.
612 File name of a base image (see @option{create} subcommand)
614 If this option is set to @code{on}, the image is encrypted.
618 User Mode Linux Copy On Write image format. It is supported only for
619 compatibility with previous versions.
623 File name of a base image (see @option{create} subcommand)
627 VirtualBox 1.1 compatible image format.
631 If this option is set to @code{on}, the image is created with metadata
636 VMware 3 and 4 compatible image format.
641 File name of a base image (see @option{create} subcommand).
643 Create a VMDK version 6 image (instead of version 4)
645 Specifies which VMDK subformat to use. Valid options are
646 @code{monolithicSparse} (default),
647 @code{monolithicFlat},
648 @code{twoGbMaxExtentSparse},
649 @code{twoGbMaxExtentFlat} and
650 @code{streamOptimized}.
654 VirtualPC compatible image format (VHD).
658 Specifies which VHD subformat to use. Valid options are
659 @code{dynamic} (default) and @code{fixed}.
663 @subsubsection Read-only formats
664 More disk image file formats are supported in a read-only mode.
667 Bochs images of @code{growing} type.
669 Linux Compressed Loop image, useful only to reuse directly compressed
670 CD-ROM images present for example in the Knoppix CD-ROMs.
674 Parallels disk image format.
679 @subsection Using host drives
681 In addition to disk image files, QEMU can directly access host
682 devices. We describe here the usage for QEMU version >= 0.8.3.
686 On Linux, you can directly use the host device filename instead of a
687 disk image filename provided you have enough privileges to access
688 it. For example, use @file{/dev/cdrom} to access to the CDROM or
689 @file{/dev/fd0} for the floppy.
693 You can specify a CDROM device even if no CDROM is loaded. QEMU has
694 specific code to detect CDROM insertion or removal. CDROM ejection by
695 the guest OS is supported. Currently only data CDs are supported.
697 You can specify a floppy device even if no floppy is loaded. Floppy
698 removal is currently not detected accurately (if you change floppy
699 without doing floppy access while the floppy is not loaded, the guest
700 OS will think that the same floppy is loaded).
702 Hard disks can be used. Normally you must specify the whole disk
703 (@file{/dev/hdb} instead of @file{/dev/hdb1}) so that the guest OS can
704 see it as a partitioned disk. WARNING: unless you know what you do, it
705 is better to only make READ-ONLY accesses to the hard disk otherwise
706 you may corrupt your host data (use the @option{-snapshot} command
707 line option or modify the device permissions accordingly).
710 @subsubsection Windows
714 The preferred syntax is the drive letter (e.g. @file{d:}). The
715 alternate syntax @file{\\.\d:} is supported. @file{/dev/cdrom} is
716 supported as an alias to the first CDROM drive.
718 Currently there is no specific code to handle removable media, so it
719 is better to use the @code{change} or @code{eject} monitor commands to
720 change or eject media.
722 Hard disks can be used with the syntax: @file{\\.\PhysicalDrive@var{N}}
723 where @var{N} is the drive number (0 is the first hard disk).
725 WARNING: unless you know what you do, it is better to only make
726 READ-ONLY accesses to the hard disk otherwise you may corrupt your
727 host data (use the @option{-snapshot} command line so that the
728 modifications are written in a temporary file).
732 @subsubsection Mac OS X
734 @file{/dev/cdrom} is an alias to the first CDROM.
736 Currently there is no specific code to handle removable media, so it
737 is better to use the @code{change} or @code{eject} monitor commands to
738 change or eject media.
740 @node disk_images_fat_images
741 @subsection Virtual FAT disk images
743 QEMU can automatically create a virtual FAT disk image from a
744 directory tree. In order to use it, just type:
747 qemu-system-i386 linux.img -hdb fat:/my_directory
750 Then you access access to all the files in the @file{/my_directory}
751 directory without having to copy them in a disk image or to export
752 them via SAMBA or NFS. The default access is @emph{read-only}.
754 Floppies can be emulated with the @code{:floppy:} option:
757 qemu-system-i386 linux.img -fda fat:floppy:/my_directory
760 A read/write support is available for testing (beta stage) with the
764 qemu-system-i386 linux.img -fda fat:floppy:rw:/my_directory
767 What you should @emph{never} do:
769 @item use non-ASCII filenames ;
770 @item use "-snapshot" together with ":rw:" ;
771 @item expect it to work when loadvm'ing ;
772 @item write to the FAT directory on the host system while accessing it with the guest system.
775 @node disk_images_nbd
776 @subsection NBD access
778 QEMU can access directly to block device exported using the Network Block Device
782 qemu-system-i386 linux.img -hdb nbd://my_nbd_server.mydomain.org:1024/
785 If the NBD server is located on the same host, you can use an unix socket instead
789 qemu-system-i386 linux.img -hdb nbd+unix://?socket=/tmp/my_socket
792 In this case, the block device must be exported using qemu-nbd:
795 qemu-nbd --socket=/tmp/my_socket my_disk.qcow2
798 The use of qemu-nbd allows to share a disk between several guests:
800 qemu-nbd --socket=/tmp/my_socket --share=2 my_disk.qcow2
804 and then you can use it with two guests:
806 qemu-system-i386 linux1.img -hdb nbd+unix://?socket=/tmp/my_socket
807 qemu-system-i386 linux2.img -hdb nbd+unix://?socket=/tmp/my_socket
810 If the nbd-server uses named exports (supported since NBD 2.9.18, or with QEMU's
811 own embedded NBD server), you must specify an export name in the URI:
813 qemu-system-i386 -cdrom nbd://localhost/debian-500-ppc-netinst
814 qemu-system-i386 -cdrom nbd://localhost/openSUSE-11.1-ppc-netinst
817 The URI syntax for NBD is supported since QEMU 1.3. An alternative syntax is
818 also available. Here are some example of the older syntax:
820 qemu-system-i386 linux.img -hdb nbd:my_nbd_server.mydomain.org:1024
821 qemu-system-i386 linux2.img -hdb nbd:unix:/tmp/my_socket
822 qemu-system-i386 -cdrom nbd:localhost:10809:exportname=debian-500-ppc-netinst
825 @node disk_images_sheepdog
826 @subsection Sheepdog disk images
828 Sheepdog is a distributed storage system for QEMU. It provides highly
829 available block level storage volumes that can be attached to
830 QEMU-based virtual machines.
832 You can create a Sheepdog disk image with the command:
834 qemu-img create sheepdog:///@var{image} @var{size}
836 where @var{image} is the Sheepdog image name and @var{size} is its
839 To import the existing @var{filename} to Sheepdog, you can use a
842 qemu-img convert @var{filename} sheepdog:///@var{image}
845 You can boot from the Sheepdog disk image with the command:
847 qemu-system-i386 sheepdog:///@var{image}
850 You can also create a snapshot of the Sheepdog image like qcow2.
852 qemu-img snapshot -c @var{tag} sheepdog:///@var{image}
854 where @var{tag} is a tag name of the newly created snapshot.
856 To boot from the Sheepdog snapshot, specify the tag name of the
859 qemu-system-i386 sheepdog:///@var{image}#@var{tag}
862 You can create a cloned image from the existing snapshot.
864 qemu-img create -b sheepdog:///@var{base}#@var{tag} sheepdog:///@var{image}
866 where @var{base} is a image name of the source snapshot and @var{tag}
869 You can use an unix socket instead of an inet socket:
872 qemu-system-i386 sheepdog+unix:///@var{image}?socket=@var{path}
875 If the Sheepdog daemon doesn't run on the local host, you need to
876 specify one of the Sheepdog servers to connect to.
878 qemu-img create sheepdog://@var{hostname}:@var{port}/@var{image} @var{size}
879 qemu-system-i386 sheepdog://@var{hostname}:@var{port}/@var{image}
882 @node disk_images_iscsi
883 @subsection iSCSI LUNs
885 iSCSI is a popular protocol used to access SCSI devices across a computer
888 There are two different ways iSCSI devices can be used by QEMU.
890 The first method is to mount the iSCSI LUN on the host, and make it appear as
891 any other ordinary SCSI device on the host and then to access this device as a
892 /dev/sd device from QEMU. How to do this differs between host OSes.
894 The second method involves using the iSCSI initiator that is built into
895 QEMU. This provides a mechanism that works the same way regardless of which
896 host OS you are running QEMU on. This section will describe this second method
897 of using iSCSI together with QEMU.
899 In QEMU, iSCSI devices are described using special iSCSI URLs
903 iscsi://[<username>[%<password>]@@]<host>[:<port>]/<target-iqn-name>/<lun>
906 Username and password are optional and only used if your target is set up
907 using CHAP authentication for access control.
908 Alternatively the username and password can also be set via environment
909 variables to have these not show up in the process list
912 export LIBISCSI_CHAP_USERNAME=<username>
913 export LIBISCSI_CHAP_PASSWORD=<password>
914 iscsi://<host>/<target-iqn-name>/<lun>
917 Various session related parameters can be set via special options, either
918 in a configuration file provided via '-readconfig' or directly on the
921 If the initiator-name is not specified qemu will use a default name
922 of 'iqn.2008-11.org.linux-kvm[:<name>'] where <name> is the name of the
927 Setting a specific initiator name to use when logging in to the target
928 -iscsi initiator-name=iqn.qemu.test:my-initiator
932 Controlling which type of header digest to negotiate with the target
933 -iscsi header-digest=CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
936 These can also be set via a configuration file
939 user = "CHAP username"
940 password = "CHAP password"
941 initiator-name = "iqn.qemu.test:my-initiator"
942 # header digest is one of CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
943 header-digest = "CRC32C"
947 Setting the target name allows different options for different targets
949 [iscsi "iqn.target.name"]
950 user = "CHAP username"
951 password = "CHAP password"
952 initiator-name = "iqn.qemu.test:my-initiator"
953 # header digest is one of CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
954 header-digest = "CRC32C"
958 Howto use a configuration file to set iSCSI configuration options:
960 cat >iscsi.conf <<EOF
963 password = "my password"
964 initiator-name = "iqn.qemu.test:my-initiator"
965 header-digest = "CRC32C"
968 qemu-system-i386 -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
969 -readconfig iscsi.conf
973 Howto set up a simple iSCSI target on loopback and accessing it via QEMU:
975 This example shows how to set up an iSCSI target with one CDROM and one DISK
976 using the Linux STGT software target. This target is available on Red Hat based
977 systems as the package 'scsi-target-utils'.
979 tgtd --iscsi portal=127.0.0.1:3260
980 tgtadm --lld iscsi --op new --mode target --tid 1 -T iqn.qemu.test
981 tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 1 \
982 -b /IMAGES/disk.img --device-type=disk
983 tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 2 \
984 -b /IMAGES/cd.iso --device-type=cd
985 tgtadm --lld iscsi --op bind --mode target --tid 1 -I ALL
987 qemu-system-i386 -iscsi initiator-name=iqn.qemu.test:my-initiator \
988 -boot d -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
989 -cdrom iscsi://127.0.0.1/iqn.qemu.test/2
992 @node disk_images_gluster
993 @subsection GlusterFS disk images
995 GlusterFS is an user space distributed file system.
997 You can boot from the GlusterFS disk image with the command:
999 qemu-system-x86_64 -drive file=gluster[+@var{transport}]://[@var{server}[:@var{port}]]/@var{volname}/@var{image}[?socket=...]
1002 @var{gluster} is the protocol.
1004 @var{transport} specifies the transport type used to connect to gluster
1005 management daemon (glusterd). Valid transport types are
1006 tcp, unix and rdma. If a transport type isn't specified, then tcp
1009 @var{server} specifies the server where the volume file specification for
1010 the given volume resides. This can be either hostname, ipv4 address
1011 or ipv6 address. ipv6 address needs to be within square brackets [ ].
1012 If transport type is unix, then @var{server} field should not be specifed.
1013 Instead @var{socket} field needs to be populated with the path to unix domain
1016 @var{port} is the port number on which glusterd is listening. This is optional
1017 and if not specified, QEMU will send 0 which will make gluster to use the
1018 default port. If the transport type is unix, then @var{port} should not be
1021 @var{volname} is the name of the gluster volume which contains the disk image.
1023 @var{image} is the path to the actual disk image that resides on gluster volume.
1025 You can create a GlusterFS disk image with the command:
1027 qemu-img create gluster://@var{server}/@var{volname}/@var{image} @var{size}
1032 qemu-system-x86_64 -drive file=gluster://1.2.3.4/testvol/a.img
1033 qemu-system-x86_64 -drive file=gluster+tcp://1.2.3.4/testvol/a.img
1034 qemu-system-x86_64 -drive file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img
1035 qemu-system-x86_64 -drive file=gluster+tcp://[1:2:3:4:5:6:7:8]/testvol/dir/a.img
1036 qemu-system-x86_64 -drive file=gluster+tcp://[1:2:3:4:5:6:7:8]:24007/testvol/dir/a.img
1037 qemu-system-x86_64 -drive file=gluster+tcp://server.domain.com:24007/testvol/dir/a.img
1038 qemu-system-x86_64 -drive file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket
1039 qemu-system-x86_64 -drive file=gluster+rdma://1.2.3.4:24007/testvol/a.img
1042 @node disk_images_ssh
1043 @subsection Secure Shell (ssh) disk images
1045 You can access disk images located on a remote ssh server
1046 by using the ssh protocol:
1049 qemu-system-x86_64 -drive file=ssh://[@var{user}@@]@var{server}[:@var{port}]/@var{path}[?host_key_check=@var{host_key_check}]
1052 Alternative syntax using properties:
1055 qemu-system-x86_64 -drive file.driver=ssh[,file.user=@var{user}],file.host=@var{server}[,file.port=@var{port}],file.path=@var{path}[,file.host_key_check=@var{host_key_check}]
1058 @var{ssh} is the protocol.
1060 @var{user} is the remote user. If not specified, then the local
1063 @var{server} specifies the remote ssh server. Any ssh server can be
1064 used, but it must implement the sftp-server protocol. Most Unix/Linux
1065 systems should work without requiring any extra configuration.
1067 @var{port} is the port number on which sshd is listening. By default
1068 the standard ssh port (22) is used.
1070 @var{path} is the path to the disk image.
1072 The optional @var{host_key_check} parameter controls how the remote
1073 host's key is checked. The default is @code{yes} which means to use
1074 the local @file{.ssh/known_hosts} file. Setting this to @code{no}
1075 turns off known-hosts checking. Or you can check that the host key
1076 matches a specific fingerprint:
1077 @code{host_key_check=md5:78:45:8e:14:57:4f:d5:45:83:0a:0e:f3:49:82:c9:c8}
1078 (@code{sha1:} can also be used as a prefix, but note that OpenSSH
1079 tools only use MD5 to print fingerprints).
1081 Currently authentication must be done using ssh-agent. Other
1082 authentication methods may be supported in future.
1084 Note: The ssh driver does not obey disk flush requests (ie. to commit
1085 data to the backing disk when the guest requests it). This is because
1086 the underlying protocol (SFTP) does not support this. Thus there is a
1087 risk of guest disk corruption if the remote server or network goes
1091 @section Network emulation
1093 QEMU can simulate several network cards (PCI or ISA cards on the PC
1094 target) and can connect them to an arbitrary number of Virtual Local
1095 Area Networks (VLANs). Host TAP devices can be connected to any QEMU
1096 VLAN. VLAN can be connected between separate instances of QEMU to
1097 simulate large networks. For simpler usage, a non privileged user mode
1098 network stack can replace the TAP device to have a basic network
1103 QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
1104 connection between several network devices. These devices can be for
1105 example QEMU virtual Ethernet cards or virtual Host ethernet devices
1108 @subsection Using TAP network interfaces
1110 This is the standard way to connect QEMU to a real network. QEMU adds
1111 a virtual network device on your host (called @code{tapN}), and you
1112 can then configure it as if it was a real ethernet card.
1114 @subsubsection Linux host
1116 As an example, you can download the @file{linux-test-xxx.tar.gz}
1117 archive and copy the script @file{qemu-ifup} in @file{/etc} and
1118 configure properly @code{sudo} so that the command @code{ifconfig}
1119 contained in @file{qemu-ifup} can be executed as root. You must verify
1120 that your host kernel supports the TAP network interfaces: the
1121 device @file{/dev/net/tun} must be present.
1123 See @ref{sec_invocation} to have examples of command lines using the
1124 TAP network interfaces.
1126 @subsubsection Windows host
1128 There is a virtual ethernet driver for Windows 2000/XP systems, called
1129 TAP-Win32. But it is not included in standard QEMU for Windows,
1130 so you will need to get it separately. It is part of OpenVPN package,
1131 so download OpenVPN from : @url{http://openvpn.net/}.
1133 @subsection Using the user mode network stack
1135 By using the option @option{-net user} (default configuration if no
1136 @option{-net} option is specified), QEMU uses a completely user mode
1137 network stack (you don't need root privilege to use the virtual
1138 network). The virtual network configuration is the following:
1142 QEMU VLAN <------> Firewall/DHCP server <-----> Internet
1145 ----> DNS server (10.0.2.3)
1147 ----> SMB server (10.0.2.4)
1150 The QEMU VM behaves as if it was behind a firewall which blocks all
1151 incoming connections. You can use a DHCP client to automatically
1152 configure the network in the QEMU VM. The DHCP server assign addresses
1153 to the hosts starting from 10.0.2.15.
1155 In order to check that the user mode network is working, you can ping
1156 the address 10.0.2.2 and verify that you got an address in the range
1157 10.0.2.x from the QEMU virtual DHCP server.
1159 Note that @code{ping} is not supported reliably to the internet as it
1160 would require root privileges. It means you can only ping the local
1163 When using the built-in TFTP server, the router is also the TFTP
1166 When using the @option{-redir} option, TCP or UDP connections can be
1167 redirected from the host to the guest. It allows for example to
1168 redirect X11, telnet or SSH connections.
1170 @subsection Connecting VLANs between QEMU instances
1172 Using the @option{-net socket} option, it is possible to make VLANs
1173 that span several QEMU instances. See @ref{sec_invocation} to have a
1176 @node pcsys_other_devs
1177 @section Other Devices
1179 @subsection Inter-VM Shared Memory device
1181 With KVM enabled on a Linux host, a shared memory device is available. Guests
1182 map a POSIX shared memory region into the guest as a PCI device that enables
1183 zero-copy communication to the application level of the guests. The basic
1187 qemu-system-i386 -device ivshmem,size=<size in format accepted by -m>[,shm=<shm name>]
1190 If desired, interrupts can be sent between guest VMs accessing the same shared
1191 memory region. Interrupt support requires using a shared memory server and
1192 using a chardev socket to connect to it. The code for the shared memory server
1193 is qemu.git/contrib/ivshmem-server. An example syntax when using the shared
1197 qemu-system-i386 -device ivshmem,size=<size in format accepted by -m>[,chardev=<id>]
1198 [,msi=on][,ioeventfd=on][,vectors=n][,role=peer|master]
1199 qemu-system-i386 -chardev socket,path=<path>,id=<id>
1202 When using the server, the guest will be assigned a VM ID (>=0) that allows guests
1203 using the same server to communicate via interrupts. Guests can read their
1204 VM ID from a device register (see example code). Since receiving the shared
1205 memory region from the server is asynchronous, there is a (small) chance the
1206 guest may boot before the shared memory is attached. To allow an application
1207 to ensure shared memory is attached, the VM ID register will return -1 (an
1208 invalid VM ID) until the memory is attached. Once the shared memory is
1209 attached, the VM ID will return the guest's valid VM ID. With these semantics,
1210 the guest application can check to ensure the shared memory is attached to the
1211 guest before proceeding.
1213 The @option{role} argument can be set to either master or peer and will affect
1214 how the shared memory is migrated. With @option{role=master}, the guest will
1215 copy the shared memory on migration to the destination host. With
1216 @option{role=peer}, the guest will not be able to migrate with the device attached.
1217 With the @option{peer} case, the device should be detached and then reattached
1218 after migration using the PCI hotplug support.
1220 @node direct_linux_boot
1221 @section Direct Linux Boot
1223 This section explains how to launch a Linux kernel inside QEMU without
1224 having to make a full bootable image. It is very useful for fast Linux
1229 qemu-system-i386 -kernel arch/i386/boot/bzImage -hda root-2.4.20.img -append "root=/dev/hda"
1232 Use @option{-kernel} to provide the Linux kernel image and
1233 @option{-append} to give the kernel command line arguments. The
1234 @option{-initrd} option can be used to provide an INITRD image.
1236 When using the direct Linux boot, a disk image for the first hard disk
1237 @file{hda} is required because its boot sector is used to launch the
1240 If you do not need graphical output, you can disable it and redirect
1241 the virtual serial port and the QEMU monitor to the console with the
1242 @option{-nographic} option. The typical command line is:
1244 qemu-system-i386 -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1245 -append "root=/dev/hda console=ttyS0" -nographic
1248 Use @key{Ctrl-a c} to switch between the serial console and the
1249 monitor (@pxref{pcsys_keys}).
1252 @section USB emulation
1254 QEMU emulates a PCI UHCI USB controller. You can virtually plug
1255 virtual USB devices or real host USB devices (experimental, works only
1256 on Linux hosts). QEMU will automatically create and connect virtual USB hubs
1257 as necessary to connect multiple USB devices.
1261 * host_usb_devices::
1264 @subsection Connecting USB devices
1266 USB devices can be connected with the @option{-usbdevice} commandline option
1267 or the @code{usb_add} monitor command. Available devices are:
1271 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1273 Pointer device that uses absolute coordinates (like a touchscreen).
1274 This means QEMU is able to report the mouse position without having
1275 to grab the mouse. Also overrides the PS/2 mouse emulation when activated.
1276 @item disk:@var{file}
1277 Mass storage device based on @var{file} (@pxref{disk_images})
1278 @item host:@var{bus.addr}
1279 Pass through the host device identified by @var{bus.addr}
1281 @item host:@var{vendor_id:product_id}
1282 Pass through the host device identified by @var{vendor_id:product_id}
1285 Virtual Wacom PenPartner tablet. This device is similar to the @code{tablet}
1286 above but it can be used with the tslib library because in addition to touch
1287 coordinates it reports touch pressure.
1289 Standard USB keyboard. Will override the PS/2 keyboard (if present).
1290 @item serial:[vendorid=@var{vendor_id}][,product_id=@var{product_id}]:@var{dev}
1291 Serial converter. This emulates an FTDI FT232BM chip connected to host character
1292 device @var{dev}. The available character devices are the same as for the
1293 @code{-serial} option. The @code{vendorid} and @code{productid} options can be
1294 used to override the default 0403:6001. For instance,
1296 usb_add serial:productid=FA00:tcp:192.168.0.2:4444
1298 will connect to tcp port 4444 of ip 192.168.0.2, and plug that to the virtual
1299 serial converter, faking a Matrix Orbital LCD Display (USB ID 0403:FA00).
1301 Braille device. This will use BrlAPI to display the braille output on a real
1303 @item net:@var{options}
1304 Network adapter that supports CDC ethernet and RNDIS protocols. @var{options}
1305 specifies NIC options as with @code{-net nic,}@var{options} (see description).
1306 For instance, user-mode networking can be used with
1308 qemu-system-i386 [...OPTIONS...] -net user,vlan=0 -usbdevice net:vlan=0
1310 Currently this cannot be used in machines that support PCI NICs.
1311 @item bt[:@var{hci-type}]
1312 Bluetooth dongle whose type is specified in the same format as with
1313 the @option{-bt hci} option, @pxref{bt-hcis,,allowed HCI types}. If
1314 no type is given, the HCI logic corresponds to @code{-bt hci,vlan=0}.
1315 This USB device implements the USB Transport Layer of HCI. Example
1318 qemu-system-i386 [...OPTIONS...] -usbdevice bt:hci,vlan=3 -bt device:keyboard,vlan=3
1322 @node host_usb_devices
1323 @subsection Using host USB devices on a Linux host
1325 WARNING: this is an experimental feature. QEMU will slow down when
1326 using it. USB devices requiring real time streaming (i.e. USB Video
1327 Cameras) are not supported yet.
1330 @item If you use an early Linux 2.4 kernel, verify that no Linux driver
1331 is actually using the USB device. A simple way to do that is simply to
1332 disable the corresponding kernel module by renaming it from @file{mydriver.o}
1333 to @file{mydriver.o.disabled}.
1335 @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
1341 @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:
1343 chown -R myuid /proc/bus/usb
1346 @item Launch QEMU and do in the monitor:
1349 Device 1.2, speed 480 Mb/s
1350 Class 00: USB device 1234:5678, USB DISK
1352 You should see the list of the devices you can use (Never try to use
1353 hubs, it won't work).
1355 @item Add the device in QEMU by using:
1357 usb_add host:1234:5678
1360 Normally the guest OS should report that a new USB device is
1361 plugged. You can use the option @option{-usbdevice} to do the same.
1363 @item Now you can try to use the host USB device in QEMU.
1367 When relaunching QEMU, you may have to unplug and plug again the USB
1368 device to make it work again (this is a bug).
1371 @section VNC security
1373 The VNC server capability provides access to the graphical console
1374 of the guest VM across the network. This has a number of security
1375 considerations depending on the deployment scenarios.
1379 * vnc_sec_password::
1380 * vnc_sec_certificate::
1381 * vnc_sec_certificate_verify::
1382 * vnc_sec_certificate_pw::
1384 * vnc_sec_certificate_sasl::
1385 * vnc_generate_cert::
1389 @subsection Without passwords
1391 The simplest VNC server setup does not include any form of authentication.
1392 For this setup it is recommended to restrict it to listen on a UNIX domain
1393 socket only. For example
1396 qemu-system-i386 [...OPTIONS...] -vnc unix:/home/joebloggs/.qemu-myvm-vnc
1399 This ensures that only users on local box with read/write access to that
1400 path can access the VNC server. To securely access the VNC server from a
1401 remote machine, a combination of netcat+ssh can be used to provide a secure
1404 @node vnc_sec_password
1405 @subsection With passwords
1407 The VNC protocol has limited support for password based authentication. Since
1408 the protocol limits passwords to 8 characters it should not be considered
1409 to provide high security. The password can be fairly easily brute-forced by
1410 a client making repeat connections. For this reason, a VNC server using password
1411 authentication should be restricted to only listen on the loopback interface
1412 or UNIX domain sockets. Password authentication is not supported when operating
1413 in FIPS 140-2 compliance mode as it requires the use of the DES cipher. Password
1414 authentication is requested with the @code{password} option, and then once QEMU
1415 is running the password is set with the monitor. Until the monitor is used to
1416 set the password all clients will be rejected.
1419 qemu-system-i386 [...OPTIONS...] -vnc :1,password -monitor stdio
1420 (qemu) change vnc password
1425 @node vnc_sec_certificate
1426 @subsection With x509 certificates
1428 The QEMU VNC server also implements the VeNCrypt extension allowing use of
1429 TLS for encryption of the session, and x509 certificates for authentication.
1430 The use of x509 certificates is strongly recommended, because TLS on its
1431 own is susceptible to man-in-the-middle attacks. Basic x509 certificate
1432 support provides a secure session, but no authentication. This allows any
1433 client to connect, and provides an encrypted session.
1436 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509=/etc/pki/qemu -monitor stdio
1439 In the above example @code{/etc/pki/qemu} should contain at least three files,
1440 @code{ca-cert.pem}, @code{server-cert.pem} and @code{server-key.pem}. Unprivileged
1441 users will want to use a private directory, for example @code{$HOME/.pki/qemu}.
1442 NB the @code{server-key.pem} file should be protected with file mode 0600 to
1443 only be readable by the user owning it.
1445 @node vnc_sec_certificate_verify
1446 @subsection With x509 certificates and client verification
1448 Certificates can also provide a means to authenticate the client connecting.
1449 The server will request that the client provide a certificate, which it will
1450 then validate against the CA certificate. This is a good choice if deploying
1451 in an environment with a private internal certificate authority.
1454 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509verify=/etc/pki/qemu -monitor stdio
1458 @node vnc_sec_certificate_pw
1459 @subsection With x509 certificates, client verification and passwords
1461 Finally, the previous method can be combined with VNC password authentication
1462 to provide two layers of authentication for clients.
1465 qemu-system-i386 [...OPTIONS...] -vnc :1,password,tls,x509verify=/etc/pki/qemu -monitor stdio
1466 (qemu) change vnc password
1473 @subsection With SASL authentication
1475 The SASL authentication method is a VNC extension, that provides an
1476 easily extendable, pluggable authentication method. This allows for
1477 integration with a wide range of authentication mechanisms, such as
1478 PAM, GSSAPI/Kerberos, LDAP, SQL databases, one-time keys and more.
1479 The strength of the authentication depends on the exact mechanism
1480 configured. If the chosen mechanism also provides a SSF layer, then
1481 it will encrypt the datastream as well.
1483 Refer to the later docs on how to choose the exact SASL mechanism
1484 used for authentication, but assuming use of one supporting SSF,
1485 then QEMU can be launched with:
1488 qemu-system-i386 [...OPTIONS...] -vnc :1,sasl -monitor stdio
1491 @node vnc_sec_certificate_sasl
1492 @subsection With x509 certificates and SASL authentication
1494 If the desired SASL authentication mechanism does not supported
1495 SSF layers, then it is strongly advised to run it in combination
1496 with TLS and x509 certificates. This provides securely encrypted
1497 data stream, avoiding risk of compromising of the security
1498 credentials. This can be enabled, by combining the 'sasl' option
1499 with the aforementioned TLS + x509 options:
1502 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509,sasl -monitor stdio
1506 @node vnc_generate_cert
1507 @subsection Generating certificates for VNC
1509 The GNU TLS packages provides a command called @code{certtool} which can
1510 be used to generate certificates and keys in PEM format. At a minimum it
1511 is necessary to setup a certificate authority, and issue certificates to
1512 each server. If using certificates for authentication, then each client
1513 will also need to be issued a certificate. The recommendation is for the
1514 server to keep its certificates in either @code{/etc/pki/qemu} or for
1515 unprivileged users in @code{$HOME/.pki/qemu}.
1519 * vnc_generate_server::
1520 * vnc_generate_client::
1522 @node vnc_generate_ca
1523 @subsubsection Setup the Certificate Authority
1525 This step only needs to be performed once per organization / organizational
1526 unit. First the CA needs a private key. This key must be kept VERY secret
1527 and secure. If this key is compromised the entire trust chain of the certificates
1528 issued with it is lost.
1531 # certtool --generate-privkey > ca-key.pem
1534 A CA needs to have a public certificate. For simplicity it can be a self-signed
1535 certificate, or one issue by a commercial certificate issuing authority. To
1536 generate a self-signed certificate requires one core piece of information, the
1537 name of the organization.
1540 # cat > ca.info <<EOF
1541 cn = Name of your organization
1545 # certtool --generate-self-signed \
1546 --load-privkey ca-key.pem
1547 --template ca.info \
1548 --outfile ca-cert.pem
1551 The @code{ca-cert.pem} file should be copied to all servers and clients wishing to utilize
1552 TLS support in the VNC server. The @code{ca-key.pem} must not be disclosed/copied at all.
1554 @node vnc_generate_server
1555 @subsubsection Issuing server certificates
1557 Each server (or host) needs to be issued with a key and certificate. When connecting
1558 the certificate is sent to the client which validates it against the CA certificate.
1559 The core piece of information for a server certificate is the hostname. This should
1560 be the fully qualified hostname that the client will connect with, since the client
1561 will typically also verify the hostname in the certificate. On the host holding the
1562 secure CA private key:
1565 # cat > server.info <<EOF
1566 organization = Name of your organization
1567 cn = server.foo.example.com
1572 # certtool --generate-privkey > server-key.pem
1573 # certtool --generate-certificate \
1574 --load-ca-certificate ca-cert.pem \
1575 --load-ca-privkey ca-key.pem \
1576 --load-privkey server server-key.pem \
1577 --template server.info \
1578 --outfile server-cert.pem
1581 The @code{server-key.pem} and @code{server-cert.pem} files should now be securely copied
1582 to the server for which they were generated. The @code{server-key.pem} is security
1583 sensitive and should be kept protected with file mode 0600 to prevent disclosure.
1585 @node vnc_generate_client
1586 @subsubsection Issuing client certificates
1588 If the QEMU VNC server is to use the @code{x509verify} option to validate client
1589 certificates as its authentication mechanism, each client also needs to be issued
1590 a certificate. The client certificate contains enough metadata to uniquely identify
1591 the client, typically organization, state, city, building, etc. On the host holding
1592 the secure CA private key:
1595 # cat > client.info <<EOF
1599 organiazation = Name of your organization
1600 cn = client.foo.example.com
1605 # certtool --generate-privkey > client-key.pem
1606 # certtool --generate-certificate \
1607 --load-ca-certificate ca-cert.pem \
1608 --load-ca-privkey ca-key.pem \
1609 --load-privkey client-key.pem \
1610 --template client.info \
1611 --outfile client-cert.pem
1614 The @code{client-key.pem} and @code{client-cert.pem} files should now be securely
1615 copied to the client for which they were generated.
1618 @node vnc_setup_sasl
1620 @subsection Configuring SASL mechanisms
1622 The following documentation assumes use of the Cyrus SASL implementation on a
1623 Linux host, but the principals should apply to any other SASL impl. When SASL
1624 is enabled, the mechanism configuration will be loaded from system default
1625 SASL service config /etc/sasl2/qemu.conf. If running QEMU as an
1626 unprivileged user, an environment variable SASL_CONF_PATH can be used
1627 to make it search alternate locations for the service config.
1629 The default configuration might contain
1632 mech_list: digest-md5
1633 sasldb_path: /etc/qemu/passwd.db
1636 This says to use the 'Digest MD5' mechanism, which is similar to the HTTP
1637 Digest-MD5 mechanism. The list of valid usernames & passwords is maintained
1638 in the /etc/qemu/passwd.db file, and can be updated using the saslpasswd2
1639 command. While this mechanism is easy to configure and use, it is not
1640 considered secure by modern standards, so only suitable for developers /
1643 A more serious deployment might use Kerberos, which is done with the 'gssapi'
1648 keytab: /etc/qemu/krb5.tab
1651 For this to work the administrator of your KDC must generate a Kerberos
1652 principal for the server, with a name of 'qemu/somehost.example.com@@EXAMPLE.COM'
1653 replacing 'somehost.example.com' with the fully qualified host name of the
1654 machine running QEMU, and 'EXAMPLE.COM' with the Kerberos Realm.
1656 Other configurations will be left as an exercise for the reader. It should
1657 be noted that only Digest-MD5 and GSSAPI provides a SSF layer for data
1658 encryption. For all other mechanisms, VNC should always be configured to
1659 use TLS and x509 certificates to protect security credentials from snooping.
1664 QEMU has a primitive support to work with gdb, so that you can do
1665 'Ctrl-C' while the virtual machine is running and inspect its state.
1667 In order to use gdb, launch QEMU with the '-s' option. It will wait for a
1670 qemu-system-i386 -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1671 -append "root=/dev/hda"
1672 Connected to host network interface: tun0
1673 Waiting gdb connection on port 1234
1676 Then launch gdb on the 'vmlinux' executable:
1681 In gdb, connect to QEMU:
1683 (gdb) target remote localhost:1234
1686 Then you can use gdb normally. For example, type 'c' to launch the kernel:
1691 Here are some useful tips in order to use gdb on system code:
1695 Use @code{info reg} to display all the CPU registers.
1697 Use @code{x/10i $eip} to display the code at the PC position.
1699 Use @code{set architecture i8086} to dump 16 bit code. Then use
1700 @code{x/10i $cs*16+$eip} to dump the code at the PC position.
1703 Advanced debugging options:
1705 The default single stepping behavior is step with the IRQs and timer service routines off. It is set this way because when gdb executes a single step it expects to advance beyond the current instruction. With the IRQs and and timer service routines on, a single step might jump into the one of the interrupt or exception vectors instead of executing the current instruction. This means you may hit the same breakpoint a number of times before executing the instruction gdb wants to have executed. Because there are rare circumstances where you want to single step into an interrupt vector the behavior can be controlled from GDB. There are three commands you can query and set the single step behavior:
1707 @item maintenance packet qqemu.sstepbits
1709 This will display the MASK bits used to control the single stepping IE:
1711 (gdb) maintenance packet qqemu.sstepbits
1712 sending: "qqemu.sstepbits"
1713 received: "ENABLE=1,NOIRQ=2,NOTIMER=4"
1715 @item maintenance packet qqemu.sstep
1717 This will display the current value of the mask used when single stepping IE:
1719 (gdb) maintenance packet qqemu.sstep
1720 sending: "qqemu.sstep"
1723 @item maintenance packet Qqemu.sstep=HEX_VALUE
1725 This will change the single step mask, so if wanted to enable IRQs on the single step, but not timers, you would use:
1727 (gdb) maintenance packet Qqemu.sstep=0x5
1728 sending: "qemu.sstep=0x5"
1733 @node pcsys_os_specific
1734 @section Target OS specific information
1738 To have access to SVGA graphic modes under X11, use the @code{vesa} or
1739 the @code{cirrus} X11 driver. For optimal performances, use 16 bit
1740 color depth in the guest and the host OS.
1742 When using a 2.6 guest Linux kernel, you should add the option
1743 @code{clock=pit} on the kernel command line because the 2.6 Linux
1744 kernels make very strict real time clock checks by default that QEMU
1745 cannot simulate exactly.
1747 When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
1748 not activated because QEMU is slower with this patch. The QEMU
1749 Accelerator Module is also much slower in this case. Earlier Fedora
1750 Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporate this
1751 patch by default. Newer kernels don't have it.
1755 If you have a slow host, using Windows 95 is better as it gives the
1756 best speed. Windows 2000 is also a good choice.
1758 @subsubsection SVGA graphic modes support
1760 QEMU emulates a Cirrus Logic GD5446 Video
1761 card. All Windows versions starting from Windows 95 should recognize
1762 and use this graphic card. For optimal performances, use 16 bit color
1763 depth in the guest and the host OS.
1765 If you are using Windows XP as guest OS and if you want to use high
1766 resolution modes which the Cirrus Logic BIOS does not support (i.e. >=
1767 1280x1024x16), then you should use the VESA VBE virtual graphic card
1768 (option @option{-std-vga}).
1770 @subsubsection CPU usage reduction
1772 Windows 9x does not correctly use the CPU HLT
1773 instruction. The result is that it takes host CPU cycles even when
1774 idle. You can install the utility from
1775 @url{http://www.user.cityline.ru/~maxamn/amnhltm.zip} to solve this
1776 problem. Note that no such tool is needed for NT, 2000 or XP.
1778 @subsubsection Windows 2000 disk full problem
1780 Windows 2000 has a bug which gives a disk full problem during its
1781 installation. When installing it, use the @option{-win2k-hack} QEMU
1782 option to enable a specific workaround. After Windows 2000 is
1783 installed, you no longer need this option (this option slows down the
1786 @subsubsection Windows 2000 shutdown
1788 Windows 2000 cannot automatically shutdown in QEMU although Windows 98
1789 can. It comes from the fact that Windows 2000 does not automatically
1790 use the APM driver provided by the BIOS.
1792 In order to correct that, do the following (thanks to Struan
1793 Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
1794 Add/Troubleshoot a device => Add a new device & Next => No, select the
1795 hardware from a list & Next => NT Apm/Legacy Support & Next => Next
1796 (again) a few times. Now the driver is installed and Windows 2000 now
1797 correctly instructs QEMU to shutdown at the appropriate moment.
1799 @subsubsection Share a directory between Unix and Windows
1801 See @ref{sec_invocation} about the help of the option @option{-smb}.
1803 @subsubsection Windows XP security problem
1805 Some releases of Windows XP install correctly but give a security
1808 A problem is preventing Windows from accurately checking the
1809 license for this computer. Error code: 0x800703e6.
1812 The workaround is to install a service pack for XP after a boot in safe
1813 mode. Then reboot, and the problem should go away. Since there is no
1814 network while in safe mode, its recommended to download the full
1815 installation of SP1 or SP2 and transfer that via an ISO or using the
1816 vvfat block device ("-hdb fat:directory_which_holds_the_SP").
1818 @subsection MS-DOS and FreeDOS
1820 @subsubsection CPU usage reduction
1822 DOS does not correctly use the CPU HLT instruction. The result is that
1823 it takes host CPU cycles even when idle. You can install the utility
1824 from @url{http://www.vmware.com/software/dosidle210.zip} to solve this
1827 @node QEMU System emulator for non PC targets
1828 @chapter QEMU System emulator for non PC targets
1830 QEMU is a generic emulator and it emulates many non PC
1831 machines. Most of the options are similar to the PC emulator. The
1832 differences are mentioned in the following sections.
1835 * PowerPC System emulator::
1836 * Sparc32 System emulator::
1837 * Sparc64 System emulator::
1838 * MIPS System emulator::
1839 * ARM System emulator::
1840 * ColdFire System emulator::
1841 * Cris System emulator::
1842 * Microblaze System emulator::
1843 * SH4 System emulator::
1844 * Xtensa System emulator::
1847 @node PowerPC System emulator
1848 @section PowerPC System emulator
1849 @cindex system emulation (PowerPC)
1851 Use the executable @file{qemu-system-ppc} to simulate a complete PREP
1852 or PowerMac PowerPC system.
1854 QEMU emulates the following PowerMac peripherals:
1858 UniNorth or Grackle PCI Bridge
1860 PCI VGA compatible card with VESA Bochs Extensions
1862 2 PMAC IDE interfaces with hard disk and CD-ROM support
1868 VIA-CUDA with ADB keyboard and mouse.
1871 QEMU emulates the following PREP peripherals:
1877 PCI VGA compatible card with VESA Bochs Extensions
1879 2 IDE interfaces with hard disk and CD-ROM support
1883 NE2000 network adapters
1887 PREP Non Volatile RAM
1889 PC compatible keyboard and mouse.
1892 QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS available at
1893 @url{http://perso.magic.fr/l_indien/OpenHackWare/index.htm}.
1895 Since version 0.9.1, QEMU uses OpenBIOS @url{http://www.openbios.org/}
1896 for the g3beige and mac99 PowerMac machines. OpenBIOS is a free (GPL
1897 v2) portable firmware implementation. The goal is to implement a 100%
1898 IEEE 1275-1994 (referred to as Open Firmware) compliant firmware.
1900 @c man begin OPTIONS
1902 The following options are specific to the PowerPC emulation:
1906 @item -g @var{W}x@var{H}[x@var{DEPTH}]
1908 Set the initial VGA graphic mode. The default is 800x600x15.
1910 @item -prom-env @var{string}
1912 Set OpenBIOS variables in NVRAM, for example:
1915 qemu-system-ppc -prom-env 'auto-boot?=false' \
1916 -prom-env 'boot-device=hd:2,\yaboot' \
1917 -prom-env 'boot-args=conf=hd:2,\yaboot.conf'
1920 These variables are not used by Open Hack'Ware.
1927 More information is available at
1928 @url{http://perso.magic.fr/l_indien/qemu-ppc/}.
1930 @node Sparc32 System emulator
1931 @section Sparc32 System emulator
1932 @cindex system emulation (Sparc32)
1934 Use the executable @file{qemu-system-sparc} to simulate the following
1935 Sun4m architecture machines:
1950 SPARCstation Voyager
1957 The emulation is somewhat complete. SMP up to 16 CPUs is supported,
1958 but Linux limits the number of usable CPUs to 4.
1960 It's also possible to simulate a SPARCstation 2 (sun4c architecture),
1961 SPARCserver 1000, or SPARCcenter 2000 (sun4d architecture), but these
1962 emulators are not usable yet.
1964 QEMU emulates the following sun4m/sun4c/sun4d peripherals:
1972 Lance (Am7990) Ethernet
1974 Non Volatile RAM M48T02/M48T08
1976 Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
1977 and power/reset logic
1979 ESP SCSI controller with hard disk and CD-ROM support
1981 Floppy drive (not on SS-600MP)
1983 CS4231 sound device (only on SS-5, not working yet)
1986 The number of peripherals is fixed in the architecture. Maximum
1987 memory size depends on the machine type, for SS-5 it is 256MB and for
1990 Since version 0.8.2, QEMU uses OpenBIOS
1991 @url{http://www.openbios.org/}. OpenBIOS is a free (GPL v2) portable
1992 firmware implementation. The goal is to implement a 100% IEEE
1993 1275-1994 (referred to as Open Firmware) compliant firmware.
1995 A sample Linux 2.6 series kernel and ram disk image are available on
1996 the QEMU web site. There are still issues with NetBSD and OpenBSD, but
1997 some kernel versions work. Please note that currently Solaris kernels
1998 don't work probably due to interface issues between OpenBIOS and
2001 @c man begin OPTIONS
2003 The following options are specific to the Sparc32 emulation:
2007 @item -g @var{W}x@var{H}x[x@var{DEPTH}]
2009 Set the initial TCX graphic mode. The default is 1024x768x8, currently
2010 the only other possible mode is 1024x768x24.
2012 @item -prom-env @var{string}
2014 Set OpenBIOS variables in NVRAM, for example:
2017 qemu-system-sparc -prom-env 'auto-boot?=false' \
2018 -prom-env 'boot-device=sd(0,2,0):d' -prom-env 'boot-args=linux single'
2021 @item -M [SS-4|SS-5|SS-10|SS-20|SS-600MP|LX|Voyager|SPARCClassic] [|SPARCbook|SS-2|SS-1000|SS-2000]
2023 Set the emulated machine type. Default is SS-5.
2029 @node Sparc64 System emulator
2030 @section Sparc64 System emulator
2031 @cindex system emulation (Sparc64)
2033 Use the executable @file{qemu-system-sparc64} to simulate a Sun4u
2034 (UltraSPARC PC-like machine), Sun4v (T1 PC-like machine), or generic
2035 Niagara (T1) machine. The emulator is not usable for anything yet, but
2036 it can launch some kernels.
2038 QEMU emulates the following peripherals:
2042 UltraSparc IIi APB PCI Bridge
2044 PCI VGA compatible card with VESA Bochs Extensions
2046 PS/2 mouse and keyboard
2048 Non Volatile RAM M48T59
2050 PC-compatible serial ports
2052 2 PCI IDE interfaces with hard disk and CD-ROM support
2057 @c man begin OPTIONS
2059 The following options are specific to the Sparc64 emulation:
2063 @item -prom-env @var{string}
2065 Set OpenBIOS variables in NVRAM, for example:
2068 qemu-system-sparc64 -prom-env 'auto-boot?=false'
2071 @item -M [sun4u|sun4v|Niagara]
2073 Set the emulated machine type. The default is sun4u.
2079 @node MIPS System emulator
2080 @section MIPS System emulator
2081 @cindex system emulation (MIPS)
2083 Four executables cover simulation of 32 and 64-bit MIPS systems in
2084 both endian options, @file{qemu-system-mips}, @file{qemu-system-mipsel}
2085 @file{qemu-system-mips64} and @file{qemu-system-mips64el}.
2086 Five different machine types are emulated:
2090 A generic ISA PC-like machine "mips"
2092 The MIPS Malta prototype board "malta"
2094 An ACER Pica "pica61". This machine needs the 64-bit emulator.
2096 MIPS emulator pseudo board "mipssim"
2098 A MIPS Magnum R4000 machine "magnum". This machine needs the 64-bit emulator.
2101 The generic emulation is supported by Debian 'Etch' and is able to
2102 install Debian into a virtual disk image. The following devices are
2107 A range of MIPS CPUs, default is the 24Kf
2109 PC style serial port
2116 The Malta emulation supports the following devices:
2120 Core board with MIPS 24Kf CPU and Galileo system controller
2122 PIIX4 PCI/USB/SMbus controller
2124 The Multi-I/O chip's serial device
2126 PCI network cards (PCnet32 and others)
2128 Malta FPGA serial device
2130 Cirrus (default) or any other PCI VGA graphics card
2133 The ACER Pica emulation supports:
2139 PC-style IRQ and DMA controllers
2146 The mipssim pseudo board emulation provides an environment similar
2147 to what the proprietary MIPS emulator uses for running Linux.
2152 A range of MIPS CPUs, default is the 24Kf
2154 PC style serial port
2156 MIPSnet network emulation
2159 The MIPS Magnum R4000 emulation supports:
2165 PC-style IRQ controller
2175 @node ARM System emulator
2176 @section ARM System emulator
2177 @cindex system emulation (ARM)
2179 Use the executable @file{qemu-system-arm} to simulate a ARM
2180 machine. The ARM Integrator/CP board is emulated with the following
2185 ARM926E, ARM1026E, ARM946E, ARM1136 or Cortex-A8 CPU
2189 SMC 91c111 Ethernet adapter
2191 PL110 LCD controller
2193 PL050 KMI with PS/2 keyboard and mouse.
2195 PL181 MultiMedia Card Interface with SD card.
2198 The ARM Versatile baseboard is emulated with the following devices:
2202 ARM926E, ARM1136 or Cortex-A8 CPU
2204 PL190 Vectored Interrupt Controller
2208 SMC 91c111 Ethernet adapter
2210 PL110 LCD controller
2212 PL050 KMI with PS/2 keyboard and mouse.
2214 PCI host bridge. Note the emulated PCI bridge only provides access to
2215 PCI memory space. It does not provide access to PCI IO space.
2216 This means some devices (eg. ne2k_pci NIC) are not usable, and others
2217 (eg. rtl8139 NIC) are only usable when the guest drivers use the memory
2218 mapped control registers.
2220 PCI OHCI USB controller.
2222 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices.
2224 PL181 MultiMedia Card Interface with SD card.
2227 Several variants of the ARM RealView baseboard are emulated,
2228 including the EB, PB-A8 and PBX-A9. Due to interactions with the
2229 bootloader, only certain Linux kernel configurations work out
2230 of the box on these boards.
2232 Kernels for the PB-A8 board should have CONFIG_REALVIEW_HIGH_PHYS_OFFSET
2233 enabled in the kernel, and expect 512M RAM. Kernels for The PBX-A9 board
2234 should have CONFIG_SPARSEMEM enabled, CONFIG_REALVIEW_HIGH_PHYS_OFFSET
2235 disabled and expect 1024M RAM.
2237 The following devices are emulated:
2241 ARM926E, ARM1136, ARM11MPCore, Cortex-A8 or Cortex-A9 MPCore CPU
2243 ARM AMBA Generic/Distributed Interrupt Controller
2247 SMC 91c111 or SMSC LAN9118 Ethernet adapter
2249 PL110 LCD controller
2251 PL050 KMI with PS/2 keyboard and mouse
2255 PCI OHCI USB controller
2257 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices
2259 PL181 MultiMedia Card Interface with SD card.
2262 The XScale-based clamshell PDA models ("Spitz", "Akita", "Borzoi"
2263 and "Terrier") emulation includes the following peripherals:
2267 Intel PXA270 System-on-chip (ARM V5TE core)
2271 IBM/Hitachi DSCM microdrive in a PXA PCMCIA slot - not in "Akita"
2273 On-chip OHCI USB controller
2275 On-chip LCD controller
2277 On-chip Real Time Clock
2279 TI ADS7846 touchscreen controller on SSP bus
2281 Maxim MAX1111 analog-digital converter on I@math{^2}C bus
2283 GPIO-connected keyboard controller and LEDs
2285 Secure Digital card connected to PXA MMC/SD host
2289 WM8750 audio CODEC on I@math{^2}C and I@math{^2}S busses
2292 The Palm Tungsten|E PDA (codename "Cheetah") emulation includes the
2297 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
2299 ROM and RAM memories (ROM firmware image can be loaded with -option-rom)
2301 On-chip LCD controller
2303 On-chip Real Time Clock
2305 TI TSC2102i touchscreen controller / analog-digital converter / Audio
2306 CODEC, connected through MicroWire and I@math{^2}S busses
2308 GPIO-connected matrix keypad
2310 Secure Digital card connected to OMAP MMC/SD host
2315 Nokia N800 and N810 internet tablets (known also as RX-34 and RX-44 / 48)
2316 emulation supports the following elements:
2320 Texas Instruments OMAP2420 System-on-chip (ARM 1136 core)
2322 RAM and non-volatile OneNAND Flash memories
2324 Display connected to EPSON remote framebuffer chip and OMAP on-chip
2325 display controller and a LS041y3 MIPI DBI-C controller
2327 TI TSC2301 (in N800) and TI TSC2005 (in N810) touchscreen controllers
2328 driven through SPI bus
2330 National Semiconductor LM8323-controlled qwerty keyboard driven
2331 through I@math{^2}C bus
2333 Secure Digital card connected to OMAP MMC/SD host
2335 Three OMAP on-chip UARTs and on-chip STI debugging console
2337 A Bluetooth(R) transceiver and HCI connected to an UART
2339 Mentor Graphics "Inventra" dual-role USB controller embedded in a TI
2340 TUSB6010 chip - only USB host mode is supported
2342 TI TMP105 temperature sensor driven through I@math{^2}C bus
2344 TI TWL92230C power management companion with an RTC on I@math{^2}C bus
2346 Nokia RETU and TAHVO multi-purpose chips with an RTC, connected
2350 The Luminary Micro Stellaris LM3S811EVB emulation includes the following
2357 64k Flash and 8k SRAM.
2359 Timers, UARTs, ADC and I@math{^2}C interface.
2361 OSRAM Pictiva 96x16 OLED with SSD0303 controller on I@math{^2}C bus.
2364 The Luminary Micro Stellaris LM3S6965EVB emulation includes the following
2371 256k Flash and 64k SRAM.
2373 Timers, UARTs, ADC, I@math{^2}C and SSI interfaces.
2375 OSRAM Pictiva 128x64 OLED with SSD0323 controller connected via SSI.
2378 The Freecom MusicPal internet radio emulation includes the following
2383 Marvell MV88W8618 ARM core.
2385 32 MB RAM, 256 KB SRAM, 8 MB flash.
2389 MV88W8xx8 Ethernet controller
2391 MV88W8618 audio controller, WM8750 CODEC and mixer
2393 128×64 display with brightness control
2395 2 buttons, 2 navigation wheels with button function
2398 The Siemens SX1 models v1 and v2 (default) basic emulation.
2399 The emulation includes the following elements:
2403 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
2405 ROM and RAM memories (ROM firmware image can be loaded with -pflash)
2407 1 Flash of 16MB and 1 Flash of 8MB
2411 On-chip LCD controller
2413 On-chip Real Time Clock
2415 Secure Digital card connected to OMAP MMC/SD host
2420 A Linux 2.6 test image is available on the QEMU web site. More
2421 information is available in the QEMU mailing-list archive.
2423 @c man begin OPTIONS
2425 The following options are specific to the ARM emulation:
2430 Enable semihosting syscall emulation.
2432 On ARM this implements the "Angel" interface.
2434 Note that this allows guest direct access to the host filesystem,
2435 so should only be used with trusted guest OS.
2439 @node ColdFire System emulator
2440 @section ColdFire System emulator
2441 @cindex system emulation (ColdFire)
2442 @cindex system emulation (M68K)
2444 Use the executable @file{qemu-system-m68k} to simulate a ColdFire machine.
2445 The emulator is able to boot a uClinux kernel.
2447 The M5208EVB emulation includes the following devices:
2451 MCF5208 ColdFire V2 Microprocessor (ISA A+ with EMAC).
2453 Three Two on-chip UARTs.
2455 Fast Ethernet Controller (FEC)
2458 The AN5206 emulation includes the following devices:
2462 MCF5206 ColdFire V2 Microprocessor.
2467 @c man begin OPTIONS
2469 The following options are specific to the ColdFire emulation:
2474 Enable semihosting syscall emulation.
2476 On M68K this implements the "ColdFire GDB" interface used by libgloss.
2478 Note that this allows guest direct access to the host filesystem,
2479 so should only be used with trusted guest OS.
2483 @node Cris System emulator
2484 @section Cris System emulator
2485 @cindex system emulation (Cris)
2489 @node Microblaze System emulator
2490 @section Microblaze System emulator
2491 @cindex system emulation (Microblaze)
2495 @node SH4 System emulator
2496 @section SH4 System emulator
2497 @cindex system emulation (SH4)
2501 @node Xtensa System emulator
2502 @section Xtensa System emulator
2503 @cindex system emulation (Xtensa)
2505 Two executables cover simulation of both Xtensa endian options,
2506 @file{qemu-system-xtensa} and @file{qemu-system-xtensaeb}.
2507 Two different machine types are emulated:
2511 Xtensa emulator pseudo board "sim"
2513 Avnet LX60/LX110/LX200 board
2516 The sim pseudo board emulation provides an environment similar
2517 to one provided by the proprietary Tensilica ISS.
2522 A range of Xtensa CPUs, default is the DC232B
2524 Console and filesystem access via semihosting calls
2527 The Avnet LX60/LX110/LX200 emulation supports:
2531 A range of Xtensa CPUs, default is the DC232B
2535 OpenCores 10/100 Mbps Ethernet MAC
2538 @c man begin OPTIONS
2540 The following options are specific to the Xtensa emulation:
2545 Enable semihosting syscall emulation.
2547 Xtensa semihosting provides basic file IO calls, such as open/read/write/seek/select.
2548 Tensilica baremetal libc for ISS and linux platform "sim" use this interface.
2550 Note that this allows guest direct access to the host filesystem,
2551 so should only be used with trusted guest OS.
2554 @node QEMU User space emulator
2555 @chapter QEMU User space emulator
2558 * Supported Operating Systems ::
2559 * Linux User space emulator::
2560 * BSD User space emulator ::
2563 @node Supported Operating Systems
2564 @section Supported Operating Systems
2566 The following OS are supported in user space emulation:
2570 Linux (referred as qemu-linux-user)
2572 BSD (referred as qemu-bsd-user)
2575 @node Linux User space emulator
2576 @section Linux User space emulator
2581 * Command line options::
2586 @subsection Quick Start
2588 In order to launch a Linux process, QEMU needs the process executable
2589 itself and all the target (x86) dynamic libraries used by it.
2593 @item On x86, you can just try to launch any process by using the native
2597 qemu-i386 -L / /bin/ls
2600 @code{-L /} tells that the x86 dynamic linker must be searched with a
2603 @item Since QEMU is also a linux process, you can launch QEMU with
2604 QEMU (NOTE: you can only do that if you compiled QEMU from the sources):
2607 qemu-i386 -L / qemu-i386 -L / /bin/ls
2610 @item On non x86 CPUs, you need first to download at least an x86 glibc
2611 (@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
2612 @code{LD_LIBRARY_PATH} is not set:
2615 unset LD_LIBRARY_PATH
2618 Then you can launch the precompiled @file{ls} x86 executable:
2621 qemu-i386 tests/i386/ls
2623 You can look at @file{scripts/qemu-binfmt-conf.sh} so that
2624 QEMU is automatically launched by the Linux kernel when you try to
2625 launch x86 executables. It requires the @code{binfmt_misc} module in the
2628 @item The x86 version of QEMU is also included. You can try weird things such as:
2630 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 \
2631 /usr/local/qemu-i386/bin/ls-i386
2637 @subsection Wine launch
2641 @item Ensure that you have a working QEMU with the x86 glibc
2642 distribution (see previous section). In order to verify it, you must be
2646 qemu-i386 /usr/local/qemu-i386/bin/ls-i386
2649 @item Download the binary x86 Wine install
2650 (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
2652 @item Configure Wine on your account. Look at the provided script
2653 @file{/usr/local/qemu-i386/@/bin/wine-conf.sh}. Your previous
2654 @code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
2656 @item Then you can try the example @file{putty.exe}:
2659 qemu-i386 /usr/local/qemu-i386/wine/bin/wine \
2660 /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
2665 @node Command line options
2666 @subsection Command line options
2669 usage: qemu-i386 [-h] [-d] [-L path] [-s size] [-cpu model] [-g port] [-B offset] [-R size] program [arguments...]
2676 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
2678 Set the x86 stack size in bytes (default=524288)
2680 Select CPU model (-cpu help for list and additional feature selection)
2681 @item -ignore-environment
2682 Start with an empty environment. Without this option,
2683 the initial environment is a copy of the caller's environment.
2684 @item -E @var{var}=@var{value}
2685 Set environment @var{var} to @var{value}.
2687 Remove @var{var} from the environment.
2689 Offset guest address by the specified number of bytes. This is useful when
2690 the address region required by guest applications is reserved on the host.
2691 This option is currently only supported on some hosts.
2693 Pre-allocate a guest virtual address space of the given size (in bytes).
2694 "G", "M", and "k" suffixes may be used when specifying the size.
2701 Activate logging of the specified items (use '-d help' for a list of log items)
2703 Act as if the host page size was 'pagesize' bytes
2705 Wait gdb connection to port
2707 Run the emulation in single step mode.
2710 Environment variables:
2714 Print system calls and arguments similar to the 'strace' program
2715 (NOTE: the actual 'strace' program will not work because the user
2716 space emulator hasn't implemented ptrace). At the moment this is
2717 incomplete. All system calls that don't have a specific argument
2718 format are printed with information for six arguments. Many
2719 flag-style arguments don't have decoders and will show up as numbers.
2722 @node Other binaries
2723 @subsection Other binaries
2725 @cindex user mode (Alpha)
2726 @command{qemu-alpha} TODO.
2728 @cindex user mode (ARM)
2729 @command{qemu-armeb} TODO.
2731 @cindex user mode (ARM)
2732 @command{qemu-arm} is also capable of running ARM "Angel" semihosted ELF
2733 binaries (as implemented by the arm-elf and arm-eabi Newlib/GDB
2734 configurations), and arm-uclinux bFLT format binaries.
2736 @cindex user mode (ColdFire)
2737 @cindex user mode (M68K)
2738 @command{qemu-m68k} is capable of running semihosted binaries using the BDM
2739 (m5xxx-ram-hosted.ld) or m68k-sim (sim.ld) syscall interfaces, and
2740 coldfire uClinux bFLT format binaries.
2742 The binary format is detected automatically.
2744 @cindex user mode (Cris)
2745 @command{qemu-cris} TODO.
2747 @cindex user mode (i386)
2748 @command{qemu-i386} TODO.
2749 @command{qemu-x86_64} TODO.
2751 @cindex user mode (Microblaze)
2752 @command{qemu-microblaze} TODO.
2754 @cindex user mode (MIPS)
2755 @command{qemu-mips} TODO.
2756 @command{qemu-mipsel} TODO.
2758 @cindex user mode (PowerPC)
2759 @command{qemu-ppc64abi32} TODO.
2760 @command{qemu-ppc64} TODO.
2761 @command{qemu-ppc} TODO.
2763 @cindex user mode (SH4)
2764 @command{qemu-sh4eb} TODO.
2765 @command{qemu-sh4} TODO.
2767 @cindex user mode (SPARC)
2768 @command{qemu-sparc} can execute Sparc32 binaries (Sparc32 CPU, 32 bit ABI).
2770 @command{qemu-sparc32plus} can execute Sparc32 and SPARC32PLUS binaries
2771 (Sparc64 CPU, 32 bit ABI).
2773 @command{qemu-sparc64} can execute some Sparc64 (Sparc64 CPU, 64 bit ABI) and
2774 SPARC32PLUS binaries (Sparc64 CPU, 32 bit ABI).
2776 @node BSD User space emulator
2777 @section BSD User space emulator
2782 * BSD Command line options::
2786 @subsection BSD Status
2790 target Sparc64 on Sparc64: Some trivial programs work.
2793 @node BSD Quick Start
2794 @subsection Quick Start
2796 In order to launch a BSD process, QEMU needs the process executable
2797 itself and all the target dynamic libraries used by it.
2801 @item On Sparc64, you can just try to launch any process by using the native
2805 qemu-sparc64 /bin/ls
2810 @node BSD Command line options
2811 @subsection Command line options
2814 usage: qemu-sparc64 [-h] [-d] [-L path] [-s size] [-bsd type] program [arguments...]
2821 Set the library root path (default=/)
2823 Set the stack size in bytes (default=524288)
2824 @item -ignore-environment
2825 Start with an empty environment. Without this option,
2826 the initial environment is a copy of the caller's environment.
2827 @item -E @var{var}=@var{value}
2828 Set environment @var{var} to @var{value}.
2830 Remove @var{var} from the environment.
2832 Set the type of the emulated BSD Operating system. Valid values are
2833 FreeBSD, NetBSD and OpenBSD (default).
2840 Activate logging of the specified items (use '-d help' for a list of log items)
2842 Act as if the host page size was 'pagesize' bytes
2844 Run the emulation in single step mode.
2848 @chapter Compilation from the sources
2853 * Cross compilation for Windows with Linux::
2861 @subsection Compilation
2863 First you must decompress the sources:
2866 tar zxvf qemu-x.y.z.tar.gz
2870 Then you configure QEMU and build it (usually no options are needed):
2876 Then type as root user:
2880 to install QEMU in @file{/usr/local}.
2886 @item Install the current versions of MSYS and MinGW from
2887 @url{http://www.mingw.org/}. You can find detailed installation
2888 instructions in the download section and the FAQ.
2891 the MinGW development library of SDL 1.2.x
2892 (@file{SDL-devel-1.2.x-@/mingw32.tar.gz}) from
2893 @url{http://www.libsdl.org}. Unpack it in a temporary place and
2894 edit the @file{sdl-config} script so that it gives the
2895 correct SDL directory when invoked.
2897 @item Install the MinGW version of zlib and make sure
2898 @file{zlib.h} and @file{libz.dll.a} are in
2899 MinGW's default header and linker search paths.
2901 @item Extract the current version of QEMU.
2903 @item Start the MSYS shell (file @file{msys.bat}).
2905 @item Change to the QEMU directory. Launch @file{./configure} and
2906 @file{make}. If you have problems using SDL, verify that
2907 @file{sdl-config} can be launched from the MSYS command line.
2909 @item You can install QEMU in @file{Program Files/QEMU} by typing
2910 @file{make install}. Don't forget to copy @file{SDL.dll} in
2911 @file{Program Files/QEMU}.
2915 @node Cross compilation for Windows with Linux
2916 @section Cross compilation for Windows with Linux
2920 Install the MinGW cross compilation tools available at
2921 @url{http://www.mingw.org/}.
2924 the MinGW development library of SDL 1.2.x
2925 (@file{SDL-devel-1.2.x-@/mingw32.tar.gz}) from
2926 @url{http://www.libsdl.org}. Unpack it in a temporary place and
2927 edit the @file{sdl-config} script so that it gives the
2928 correct SDL directory when invoked. Set up the @code{PATH} environment
2929 variable so that @file{sdl-config} can be launched by
2930 the QEMU configuration script.
2932 @item Install the MinGW version of zlib and make sure
2933 @file{zlib.h} and @file{libz.dll.a} are in
2934 MinGW's default header and linker search paths.
2937 Configure QEMU for Windows cross compilation:
2939 PATH=/usr/i686-pc-mingw32/sys-root/mingw/bin:$PATH ./configure --cross-prefix='i686-pc-mingw32-'
2941 The example assumes @file{sdl-config} is installed under @file{/usr/i686-pc-mingw32/sys-root/mingw/bin} and
2942 MinGW cross compilation tools have names like @file{i686-pc-mingw32-gcc} and @file{i686-pc-mingw32-strip}.
2943 We set the @code{PATH} environment variable to ensure the MinGW version of @file{sdl-config} is used and
2944 use --cross-prefix to specify the name of the cross compiler.
2945 You can also use --prefix to set the Win32 install path which defaults to @file{c:/Program Files/QEMU}.
2947 Under Fedora Linux, you can run:
2949 yum -y install mingw32-gcc mingw32-SDL mingw32-zlib
2951 to get a suitable cross compilation environment.
2953 @item You can install QEMU in the installation directory by typing
2954 @code{make install}. Don't forget to copy @file{SDL.dll} and @file{zlib1.dll} into the
2955 installation directory.
2959 Wine can be used to launch the resulting qemu-system-i386.exe
2960 and all other qemu-system-@var{target}.exe compiled for Win32.
2965 The Mac OS X patches are not fully merged in QEMU, so you should look
2966 at the QEMU mailing list archive to have all the necessary
2970 @section Make targets
2976 Make everything which is typically needed.
2985 Remove most files which were built during make.
2987 @item make distclean
2988 Remove everything which was built during make.
2994 Create documentation in dvi, html, info or pdf format.
2999 @item make defconfig
3000 (Re-)create some build configuration files.
3001 User made changes will be overwritten.
3012 QEMU is a trademark of Fabrice Bellard.
3014 QEMU is released under the GNU General Public License (TODO: add link).
3015 Parts of QEMU have specific licenses, see file LICENSE.
3017 TODO (refer to file LICENSE, include it, include the GPL?)
3031 @section Concept Index
3032 This is the main index. Should we combine all keywords in one index? TODO
3035 @node Function Index
3036 @section Function Index
3037 This index could be used for command line options and monitor functions.
3040 @node Keystroke Index
3041 @section Keystroke Index
3043 This is a list of all keystrokes which have a special function
3044 in system emulation.
3049 @section Program Index
3052 @node Data Type Index
3053 @section Data Type Index
3055 This index could be used for qdev device names and options.
3059 @node Variable Index
3060 @section Variable Index