1 \input texinfo @c -*- texinfo -*-
3 @setfilename qemu-doc.info
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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)
148 @cindex installation (Mac OS X)
150 Download the experimental binary installer at
151 @url{http://www.free.oszoo.org/@/download.html}.
152 TODO (no longer available)
154 @node QEMU PC System emulator
155 @chapter QEMU PC System emulator
156 @cindex system emulation (PC)
159 * pcsys_introduction:: Introduction
160 * pcsys_quickstart:: Quick Start
161 * sec_invocation:: Invocation
163 * pcsys_monitor:: QEMU Monitor
164 * disk_images:: Disk Images
165 * pcsys_network:: Network emulation
166 * pcsys_other_devs:: Other Devices
167 * direct_linux_boot:: Direct Linux Boot
168 * pcsys_usb:: USB emulation
169 * vnc_security:: VNC security
170 * gdb_usage:: GDB usage
171 * pcsys_os_specific:: Target OS specific information
174 @node pcsys_introduction
175 @section Introduction
177 @c man begin DESCRIPTION
179 The QEMU PC System emulator simulates the
180 following peripherals:
184 i440FX host PCI bridge and PIIX3 PCI to ISA bridge
186 Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
187 extensions (hardware level, including all non standard modes).
189 PS/2 mouse and keyboard
191 2 PCI IDE interfaces with hard disk and CD-ROM support
195 PCI and ISA network adapters
199 Creative SoundBlaster 16 sound card
201 ENSONIQ AudioPCI ES1370 sound card
203 Intel 82801AA AC97 Audio compatible sound card
205 Intel HD Audio Controller and HDA codec
207 Adlib (OPL2) - Yamaha YM3812 compatible chip
209 Gravis Ultrasound GF1 sound card
211 CS4231A compatible sound card
213 PCI UHCI USB controller and a virtual USB hub.
216 SMP is supported with up to 255 CPUs.
218 QEMU uses the PC BIOS from the Seabios project and the Plex86/Bochs LGPL
221 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
223 QEMU uses GUS emulation (GUSEMU32 @url{http://www.deinmeister.de/gusemu/})
224 by Tibor "TS" Schütz.
226 Note that, by default, GUS shares IRQ(7) with parallel ports and so
227 QEMU must be told to not have parallel ports to have working GUS.
230 qemu-system-i386 dos.img -soundhw gus -parallel none
235 qemu-system-i386 dos.img -device gus,irq=5
238 Or some other unclaimed IRQ.
240 CS4231A is the chip used in Windows Sound System and GUSMAX products
244 @node pcsys_quickstart
248 Download and uncompress the linux image (@file{linux.img}) and type:
251 qemu-system-i386 linux.img
254 Linux should boot and give you a prompt.
260 @c man begin SYNOPSIS
261 usage: qemu-system-i386 [options] [@var{disk_image}]
266 @var{disk_image} is a raw hard disk image for IDE hard disk 0. Some
267 targets do not need a disk image.
269 @include qemu-options.texi
278 During the graphical emulation, you can use special key combinations to change
279 modes. The default key mappings are shown below, but if you use @code{-alt-grab}
280 then the modifier is Ctrl-Alt-Shift (instead of Ctrl-Alt) and if you use
281 @code{-ctrl-grab} then the modifier is the right Ctrl key (instead of Ctrl-Alt):
298 Restore the screen's un-scaled dimensions
302 Switch to virtual console 'n'. Standard console mappings are:
305 Target system display
314 Toggle mouse and keyboard grab.
320 @kindex Ctrl-PageDown
321 In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
322 @key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
325 During emulation, if you are using the @option{-nographic} option, use
326 @key{Ctrl-a h} to get terminal commands:
339 Save disk data back to file (if -snapshot)
342 Toggle console timestamps
345 Send break (magic sysrq in Linux)
348 Switch between console and monitor
358 The HTML documentation of QEMU for more precise information and Linux
359 user mode emulator invocation.
369 @section QEMU Monitor
372 The QEMU monitor is used to give complex commands to the QEMU
373 emulator. You can use it to:
378 Remove or insert removable media images
379 (such as CD-ROM or floppies).
382 Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
385 @item Inspect the VM state without an external debugger.
391 The following commands are available:
393 @include qemu-monitor.texi
395 @subsection Integer expressions
397 The monitor understands integers expressions for every integer
398 argument. You can use register names to get the value of specifics
399 CPU registers by prefixing them with @emph{$}.
404 Since version 0.6.1, QEMU supports many disk image formats, including
405 growable disk images (their size increase as non empty sectors are
406 written), compressed and encrypted disk images. Version 0.8.3 added
407 the new qcow2 disk image format which is essential to support VM
411 * disk_images_quickstart:: Quick start for disk image creation
412 * disk_images_snapshot_mode:: Snapshot mode
413 * vm_snapshots:: VM snapshots
414 * qemu_img_invocation:: qemu-img Invocation
415 * qemu_nbd_invocation:: qemu-nbd Invocation
416 * disk_images_formats:: Disk image file formats
417 * host_drives:: Using host drives
418 * disk_images_fat_images:: Virtual FAT disk images
419 * disk_images_nbd:: NBD access
420 * disk_images_sheepdog:: Sheepdog disk images
421 * disk_images_iscsi:: iSCSI LUNs
422 * disk_images_gluster:: GlusterFS disk images
423 * disk_images_ssh:: Secure Shell (ssh) disk images
426 @node disk_images_quickstart
427 @subsection Quick start for disk image creation
429 You can create a disk image with the command:
431 qemu-img create myimage.img mysize
433 where @var{myimage.img} is the disk image filename and @var{mysize} is its
434 size in kilobytes. You can add an @code{M} suffix to give the size in
435 megabytes and a @code{G} suffix for gigabytes.
437 See @ref{qemu_img_invocation} for more information.
439 @node disk_images_snapshot_mode
440 @subsection Snapshot mode
442 If you use the option @option{-snapshot}, all disk images are
443 considered as read only. When sectors in written, they are written in
444 a temporary file created in @file{/tmp}. You can however force the
445 write back to the raw disk images by using the @code{commit} monitor
446 command (or @key{C-a s} in the serial console).
449 @subsection VM snapshots
451 VM snapshots are snapshots of the complete virtual machine including
452 CPU state, RAM, device state and the content of all the writable
453 disks. In order to use VM snapshots, you must have at least one non
454 removable and writable block device using the @code{qcow2} disk image
455 format. Normally this device is the first virtual hard drive.
457 Use the monitor command @code{savevm} to create a new VM snapshot or
458 replace an existing one. A human readable name can be assigned to each
459 snapshot in addition to its numerical ID.
461 Use @code{loadvm} to restore a VM snapshot and @code{delvm} to remove
462 a VM snapshot. @code{info snapshots} lists the available snapshots
463 with their associated information:
466 (qemu) info snapshots
467 Snapshot devices: hda
468 Snapshot list (from hda):
469 ID TAG VM SIZE DATE VM CLOCK
470 1 start 41M 2006-08-06 12:38:02 00:00:14.954
471 2 40M 2006-08-06 12:43:29 00:00:18.633
472 3 msys 40M 2006-08-06 12:44:04 00:00:23.514
475 A VM snapshot is made of a VM state info (its size is shown in
476 @code{info snapshots}) and a snapshot of every writable disk image.
477 The VM state info is stored in the first @code{qcow2} non removable
478 and writable block device. The disk image snapshots are stored in
479 every disk image. The size of a snapshot in a disk image is difficult
480 to evaluate and is not shown by @code{info snapshots} because the
481 associated disk sectors are shared among all the snapshots to save
482 disk space (otherwise each snapshot would need a full copy of all the
485 When using the (unrelated) @code{-snapshot} option
486 (@ref{disk_images_snapshot_mode}), you can always make VM snapshots,
487 but they are deleted as soon as you exit QEMU.
489 VM snapshots currently have the following known limitations:
492 They cannot cope with removable devices if they are removed or
493 inserted after a snapshot is done.
495 A few device drivers still have incomplete snapshot support so their
496 state is not saved or restored properly (in particular USB).
499 @node qemu_img_invocation
500 @subsection @code{qemu-img} Invocation
502 @include qemu-img.texi
504 @node qemu_nbd_invocation
505 @subsection @code{qemu-nbd} Invocation
507 @include qemu-nbd.texi
509 @node disk_images_formats
510 @subsection Disk image file formats
512 QEMU supports many image file formats that can be used with VMs as well as with
513 any of the tools (like @code{qemu-img}). This includes the preferred formats
514 raw and qcow2 as well as formats that are supported for compatibility with
515 older QEMU versions or other hypervisors.
517 Depending on the image format, different options can be passed to
518 @code{qemu-img create} and @code{qemu-img convert} using the @code{-o} option.
519 This section describes each format and the options that are supported for it.
524 Raw disk image format. This format has the advantage of
525 being simple and easily exportable to all other emulators. If your
526 file system supports @emph{holes} (for example in ext2 or ext3 on
527 Linux or NTFS on Windows), then only the written sectors will reserve
528 space. Use @code{qemu-img info} to know the real size used by the
529 image or @code{ls -ls} on Unix/Linux.
532 QEMU image format, the most versatile format. Use it to have smaller
533 images (useful if your filesystem does not supports holes, for example
534 on Windows), optional AES encryption, zlib based compression and
535 support of multiple VM snapshots.
540 Determines the qcow2 version to use. @code{compat=0.10} uses the
541 traditional image format that can be read by any QEMU since 0.10.
542 @code{compat=1.1} enables image format extensions that only QEMU 1.1 and
543 newer understand (this is the default). Amongst others, this includes
544 zero clusters, which allow efficient copy-on-read for sparse images.
547 File name of a base image (see @option{create} subcommand)
549 Image format of the base image
551 If this option is set to @code{on}, the image is encrypted with 128-bit AES-CBC.
553 The use of encryption in qcow and qcow2 images is considered to be flawed by
554 modern cryptography standards, suffering from a number of design problems:
557 @item The AES-CBC cipher is used with predictable initialization vectors based
558 on the sector number. This makes it vulnerable to chosen plaintext attacks
559 which can reveal the existence of encrypted data.
560 @item The user passphrase is directly used as the encryption key. A poorly
561 chosen or short passphrase will compromise the security of the encryption.
562 @item In the event of the passphrase being compromised there is no way to
563 change the passphrase to protect data in any qcow images. The files must
564 be cloned, using a different encryption passphrase in the new file. The
565 original file must then be securely erased using a program like shred,
566 though even this is ineffective with many modern storage technologies.
569 Use of qcow / qcow2 encryption is thus strongly discouraged. Users are
570 recommended to use an alternative encryption technology such as the
571 Linux dm-crypt / LUKS system.
574 Changes the qcow2 cluster size (must be between 512 and 2M). Smaller cluster
575 sizes can improve the image file size whereas larger cluster sizes generally
576 provide better performance.
579 Preallocation mode (allowed values: off, metadata). An image with preallocated
580 metadata is initially larger but can improve performance when the image needs
584 If this option is set to @code{on}, reference count updates are postponed with
585 the goal of avoiding metadata I/O and improving performance. This is
586 particularly interesting with @option{cache=writethrough} which doesn't batch
587 metadata updates. The tradeoff is that after a host crash, the reference count
588 tables must be rebuilt, i.e. on the next open an (automatic) @code{qemu-img
589 check -r all} is required, which may take some time.
591 This option can only be enabled if @code{compat=1.1} is specified.
594 If this option is set to @code{on}, it will turn off COW of the file. It's only
595 valid on btrfs, no effect on other file systems.
597 Btrfs has low performance when hosting a VM image file, even more when the guest
598 on the VM also using btrfs as file system. Turning off COW is a way to mitigate
599 this bad performance. Generally there are two ways to turn off COW on btrfs:
600 a) Disable it by mounting with nodatacow, then all newly created files will be
601 NOCOW. b) For an empty file, add the NOCOW file attribute. That's what this option
604 Note: this option is only valid to new or empty files. If there is an existing
605 file which is COW and has data blocks already, it couldn't be changed to NOCOW
606 by setting @code{nocow=on}. One can issue @code{lsattr filename} to check if
607 the NOCOW flag is set or not (Capital 'C' is NOCOW flag).
612 Old QEMU image format with support for backing files and compact image files
613 (when your filesystem or transport medium does not support holes).
615 When converting QED images to qcow2, you might want to consider using the
616 @code{lazy_refcounts=on} option to get a more QED-like behaviour.
621 File name of a base image (see @option{create} subcommand).
623 Image file format of backing file (optional). Useful if the format cannot be
624 autodetected because it has no header, like some vhd/vpc files.
626 Changes the cluster size (must be power-of-2 between 4K and 64K). Smaller
627 cluster sizes can improve the image file size whereas larger cluster sizes
628 generally provide better performance.
630 Changes the number of clusters per L1/L2 table (must be power-of-2 between 1
631 and 16). There is normally no need to change this value but this option can be
632 used for performance benchmarking.
636 Old QEMU image format with support for backing files, compact image files,
637 encryption and compression.
642 File name of a base image (see @option{create} subcommand)
644 If this option is set to @code{on}, the image is encrypted.
648 User Mode Linux Copy On Write image format. It is supported only for
649 compatibility with previous versions.
653 File name of a base image (see @option{create} subcommand)
657 VirtualBox 1.1 compatible image format.
661 If this option is set to @code{on}, the image is created with metadata
666 VMware 3 and 4 compatible image format.
671 File name of a base image (see @option{create} subcommand).
673 Create a VMDK version 6 image (instead of version 4)
675 Specifies which VMDK subformat to use. Valid options are
676 @code{monolithicSparse} (default),
677 @code{monolithicFlat},
678 @code{twoGbMaxExtentSparse},
679 @code{twoGbMaxExtentFlat} and
680 @code{streamOptimized}.
684 VirtualPC compatible image format (VHD).
688 Specifies which VHD subformat to use. Valid options are
689 @code{dynamic} (default) and @code{fixed}.
693 Hyper-V compatible image format (VHDX).
697 Specifies which VHDX subformat to use. Valid options are
698 @code{dynamic} (default) and @code{fixed}.
699 @item block_state_zero
700 Force use of payload blocks of type 'ZERO'.
702 Block size; min 1 MB, max 256 MB. 0 means auto-calculate based on image size.
708 @subsubsection Read-only formats
709 More disk image file formats are supported in a read-only mode.
712 Bochs images of @code{growing} type.
714 Linux Compressed Loop image, useful only to reuse directly compressed
715 CD-ROM images present for example in the Knoppix CD-ROMs.
719 Parallels disk image format.
724 @subsection Using host drives
726 In addition to disk image files, QEMU can directly access host
727 devices. We describe here the usage for QEMU version >= 0.8.3.
731 On Linux, you can directly use the host device filename instead of a
732 disk image filename provided you have enough privileges to access
733 it. For example, use @file{/dev/cdrom} to access to the CDROM or
734 @file{/dev/fd0} for the floppy.
738 You can specify a CDROM device even if no CDROM is loaded. QEMU has
739 specific code to detect CDROM insertion or removal. CDROM ejection by
740 the guest OS is supported. Currently only data CDs are supported.
742 You can specify a floppy device even if no floppy is loaded. Floppy
743 removal is currently not detected accurately (if you change floppy
744 without doing floppy access while the floppy is not loaded, the guest
745 OS will think that the same floppy is loaded).
747 Hard disks can be used. Normally you must specify the whole disk
748 (@file{/dev/hdb} instead of @file{/dev/hdb1}) so that the guest OS can
749 see it as a partitioned disk. WARNING: unless you know what you do, it
750 is better to only make READ-ONLY accesses to the hard disk otherwise
751 you may corrupt your host data (use the @option{-snapshot} command
752 line option or modify the device permissions accordingly).
755 @subsubsection Windows
759 The preferred syntax is the drive letter (e.g. @file{d:}). The
760 alternate syntax @file{\\.\d:} is supported. @file{/dev/cdrom} is
761 supported as an alias to the first CDROM drive.
763 Currently there is no specific code to handle removable media, so it
764 is better to use the @code{change} or @code{eject} monitor commands to
765 change or eject media.
767 Hard disks can be used with the syntax: @file{\\.\PhysicalDrive@var{N}}
768 where @var{N} is the drive number (0 is the first hard disk).
769 @file{/dev/hda} is supported as an alias to
770 the first hard disk drive @file{\\.\PhysicalDrive0}.
772 WARNING: unless you know what you do, it is better to only make
773 READ-ONLY accesses to the hard disk otherwise you may corrupt your
774 host data (use the @option{-snapshot} command line so that the
775 modifications are written in a temporary file).
779 @subsubsection Mac OS X
781 @file{/dev/cdrom} is an alias to the first CDROM.
783 Currently there is no specific code to handle removable media, so it
784 is better to use the @code{change} or @code{eject} monitor commands to
785 change or eject media.
787 @node disk_images_fat_images
788 @subsection Virtual FAT disk images
790 QEMU can automatically create a virtual FAT disk image from a
791 directory tree. In order to use it, just type:
794 qemu-system-i386 linux.img -hdb fat:/my_directory
797 Then you access access to all the files in the @file{/my_directory}
798 directory without having to copy them in a disk image or to export
799 them via SAMBA or NFS. The default access is @emph{read-only}.
801 Floppies can be emulated with the @code{:floppy:} option:
804 qemu-system-i386 linux.img -fda fat:floppy:/my_directory
807 A read/write support is available for testing (beta stage) with the
811 qemu-system-i386 linux.img -fda fat:floppy:rw:/my_directory
814 What you should @emph{never} do:
816 @item use non-ASCII filenames ;
817 @item use "-snapshot" together with ":rw:" ;
818 @item expect it to work when loadvm'ing ;
819 @item write to the FAT directory on the host system while accessing it with the guest system.
822 @node disk_images_nbd
823 @subsection NBD access
825 QEMU can access directly to block device exported using the Network Block Device
829 qemu-system-i386 linux.img -hdb nbd://my_nbd_server.mydomain.org:1024/
832 If the NBD server is located on the same host, you can use an unix socket instead
836 qemu-system-i386 linux.img -hdb nbd+unix://?socket=/tmp/my_socket
839 In this case, the block device must be exported using qemu-nbd:
842 qemu-nbd --socket=/tmp/my_socket my_disk.qcow2
845 The use of qemu-nbd allows sharing of a disk between several guests:
847 qemu-nbd --socket=/tmp/my_socket --share=2 my_disk.qcow2
851 and then you can use it with two guests:
853 qemu-system-i386 linux1.img -hdb nbd+unix://?socket=/tmp/my_socket
854 qemu-system-i386 linux2.img -hdb nbd+unix://?socket=/tmp/my_socket
857 If the nbd-server uses named exports (supported since NBD 2.9.18, or with QEMU's
858 own embedded NBD server), you must specify an export name in the URI:
860 qemu-system-i386 -cdrom nbd://localhost/debian-500-ppc-netinst
861 qemu-system-i386 -cdrom nbd://localhost/openSUSE-11.1-ppc-netinst
864 The URI syntax for NBD is supported since QEMU 1.3. An alternative syntax is
865 also available. Here are some example of the older syntax:
867 qemu-system-i386 linux.img -hdb nbd:my_nbd_server.mydomain.org:1024
868 qemu-system-i386 linux2.img -hdb nbd:unix:/tmp/my_socket
869 qemu-system-i386 -cdrom nbd:localhost:10809:exportname=debian-500-ppc-netinst
872 @node disk_images_sheepdog
873 @subsection Sheepdog disk images
875 Sheepdog is a distributed storage system for QEMU. It provides highly
876 available block level storage volumes that can be attached to
877 QEMU-based virtual machines.
879 You can create a Sheepdog disk image with the command:
881 qemu-img create sheepdog:///@var{image} @var{size}
883 where @var{image} is the Sheepdog image name and @var{size} is its
886 To import the existing @var{filename} to Sheepdog, you can use a
889 qemu-img convert @var{filename} sheepdog:///@var{image}
892 You can boot from the Sheepdog disk image with the command:
894 qemu-system-i386 sheepdog:///@var{image}
897 You can also create a snapshot of the Sheepdog image like qcow2.
899 qemu-img snapshot -c @var{tag} sheepdog:///@var{image}
901 where @var{tag} is a tag name of the newly created snapshot.
903 To boot from the Sheepdog snapshot, specify the tag name of the
906 qemu-system-i386 sheepdog:///@var{image}#@var{tag}
909 You can create a cloned image from the existing snapshot.
911 qemu-img create -b sheepdog:///@var{base}#@var{tag} sheepdog:///@var{image}
913 where @var{base} is a image name of the source snapshot and @var{tag}
916 You can use an unix socket instead of an inet socket:
919 qemu-system-i386 sheepdog+unix:///@var{image}?socket=@var{path}
922 If the Sheepdog daemon doesn't run on the local host, you need to
923 specify one of the Sheepdog servers to connect to.
925 qemu-img create sheepdog://@var{hostname}:@var{port}/@var{image} @var{size}
926 qemu-system-i386 sheepdog://@var{hostname}:@var{port}/@var{image}
929 @node disk_images_iscsi
930 @subsection iSCSI LUNs
932 iSCSI is a popular protocol used to access SCSI devices across a computer
935 There are two different ways iSCSI devices can be used by QEMU.
937 The first method is to mount the iSCSI LUN on the host, and make it appear as
938 any other ordinary SCSI device on the host and then to access this device as a
939 /dev/sd device from QEMU. How to do this differs between host OSes.
941 The second method involves using the iSCSI initiator that is built into
942 QEMU. This provides a mechanism that works the same way regardless of which
943 host OS you are running QEMU on. This section will describe this second method
944 of using iSCSI together with QEMU.
946 In QEMU, iSCSI devices are described using special iSCSI URLs
950 iscsi://[<username>[%<password>]@@]<host>[:<port>]/<target-iqn-name>/<lun>
953 Username and password are optional and only used if your target is set up
954 using CHAP authentication for access control.
955 Alternatively the username and password can also be set via environment
956 variables to have these not show up in the process list
959 export LIBISCSI_CHAP_USERNAME=<username>
960 export LIBISCSI_CHAP_PASSWORD=<password>
961 iscsi://<host>/<target-iqn-name>/<lun>
964 Various session related parameters can be set via special options, either
965 in a configuration file provided via '-readconfig' or directly on the
968 If the initiator-name is not specified qemu will use a default name
969 of 'iqn.2008-11.org.linux-kvm[:<name>'] where <name> is the name of the
974 Setting a specific initiator name to use when logging in to the target
975 -iscsi initiator-name=iqn.qemu.test:my-initiator
979 Controlling which type of header digest to negotiate with the target
980 -iscsi header-digest=CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
983 These can also be set via a configuration file
986 user = "CHAP username"
987 password = "CHAP password"
988 initiator-name = "iqn.qemu.test:my-initiator"
989 # header digest is one of CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
990 header-digest = "CRC32C"
994 Setting the target name allows different options for different targets
996 [iscsi "iqn.target.name"]
997 user = "CHAP username"
998 password = "CHAP password"
999 initiator-name = "iqn.qemu.test:my-initiator"
1000 # header digest is one of CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
1001 header-digest = "CRC32C"
1005 Howto use a configuration file to set iSCSI configuration options:
1007 cat >iscsi.conf <<EOF
1010 password = "my password"
1011 initiator-name = "iqn.qemu.test:my-initiator"
1012 header-digest = "CRC32C"
1015 qemu-system-i386 -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
1016 -readconfig iscsi.conf
1020 Howto set up a simple iSCSI target on loopback and accessing it via QEMU:
1022 This example shows how to set up an iSCSI target with one CDROM and one DISK
1023 using the Linux STGT software target. This target is available on Red Hat based
1024 systems as the package 'scsi-target-utils'.
1026 tgtd --iscsi portal=127.0.0.1:3260
1027 tgtadm --lld iscsi --op new --mode target --tid 1 -T iqn.qemu.test
1028 tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 1 \
1029 -b /IMAGES/disk.img --device-type=disk
1030 tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 2 \
1031 -b /IMAGES/cd.iso --device-type=cd
1032 tgtadm --lld iscsi --op bind --mode target --tid 1 -I ALL
1034 qemu-system-i386 -iscsi initiator-name=iqn.qemu.test:my-initiator \
1035 -boot d -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
1036 -cdrom iscsi://127.0.0.1/iqn.qemu.test/2
1039 @node disk_images_gluster
1040 @subsection GlusterFS disk images
1042 GlusterFS is an user space distributed file system.
1044 You can boot from the GlusterFS disk image with the command:
1046 qemu-system-x86_64 -drive file=gluster[+@var{transport}]://[@var{server}[:@var{port}]]/@var{volname}/@var{image}[?socket=...]
1049 @var{gluster} is the protocol.
1051 @var{transport} specifies the transport type used to connect to gluster
1052 management daemon (glusterd). Valid transport types are
1053 tcp, unix and rdma. If a transport type isn't specified, then tcp
1056 @var{server} specifies the server where the volume file specification for
1057 the given volume resides. This can be either hostname, ipv4 address
1058 or ipv6 address. ipv6 address needs to be within square brackets [ ].
1059 If transport type is unix, then @var{server} field should not be specifed.
1060 Instead @var{socket} field needs to be populated with the path to unix domain
1063 @var{port} is the port number on which glusterd is listening. This is optional
1064 and if not specified, QEMU will send 0 which will make gluster to use the
1065 default port. If the transport type is unix, then @var{port} should not be
1068 @var{volname} is the name of the gluster volume which contains the disk image.
1070 @var{image} is the path to the actual disk image that resides on gluster volume.
1072 You can create a GlusterFS disk image with the command:
1074 qemu-img create gluster://@var{server}/@var{volname}/@var{image} @var{size}
1079 qemu-system-x86_64 -drive file=gluster://1.2.3.4/testvol/a.img
1080 qemu-system-x86_64 -drive file=gluster+tcp://1.2.3.4/testvol/a.img
1081 qemu-system-x86_64 -drive file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img
1082 qemu-system-x86_64 -drive file=gluster+tcp://[1:2:3:4:5:6:7:8]/testvol/dir/a.img
1083 qemu-system-x86_64 -drive file=gluster+tcp://[1:2:3:4:5:6:7:8]:24007/testvol/dir/a.img
1084 qemu-system-x86_64 -drive file=gluster+tcp://server.domain.com:24007/testvol/dir/a.img
1085 qemu-system-x86_64 -drive file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket
1086 qemu-system-x86_64 -drive file=gluster+rdma://1.2.3.4:24007/testvol/a.img
1089 @node disk_images_ssh
1090 @subsection Secure Shell (ssh) disk images
1092 You can access disk images located on a remote ssh server
1093 by using the ssh protocol:
1096 qemu-system-x86_64 -drive file=ssh://[@var{user}@@]@var{server}[:@var{port}]/@var{path}[?host_key_check=@var{host_key_check}]
1099 Alternative syntax using properties:
1102 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}]
1105 @var{ssh} is the protocol.
1107 @var{user} is the remote user. If not specified, then the local
1110 @var{server} specifies the remote ssh server. Any ssh server can be
1111 used, but it must implement the sftp-server protocol. Most Unix/Linux
1112 systems should work without requiring any extra configuration.
1114 @var{port} is the port number on which sshd is listening. By default
1115 the standard ssh port (22) is used.
1117 @var{path} is the path to the disk image.
1119 The optional @var{host_key_check} parameter controls how the remote
1120 host's key is checked. The default is @code{yes} which means to use
1121 the local @file{.ssh/known_hosts} file. Setting this to @code{no}
1122 turns off known-hosts checking. Or you can check that the host key
1123 matches a specific fingerprint:
1124 @code{host_key_check=md5:78:45:8e:14:57:4f:d5:45:83:0a:0e:f3:49:82:c9:c8}
1125 (@code{sha1:} can also be used as a prefix, but note that OpenSSH
1126 tools only use MD5 to print fingerprints).
1128 Currently authentication must be done using ssh-agent. Other
1129 authentication methods may be supported in future.
1131 Note: Many ssh servers do not support an @code{fsync}-style operation.
1132 The ssh driver cannot guarantee that disk flush requests are
1133 obeyed, and this causes a risk of disk corruption if the remote
1134 server or network goes down during writes. The driver will
1135 print a warning when @code{fsync} is not supported:
1137 warning: ssh server @code{ssh.example.com:22} does not support fsync
1139 With sufficiently new versions of libssh2 and OpenSSH, @code{fsync} is
1143 @section Network emulation
1145 QEMU can simulate several network cards (PCI or ISA cards on the PC
1146 target) and can connect them to an arbitrary number of Virtual Local
1147 Area Networks (VLANs). Host TAP devices can be connected to any QEMU
1148 VLAN. VLAN can be connected between separate instances of QEMU to
1149 simulate large networks. For simpler usage, a non privileged user mode
1150 network stack can replace the TAP device to have a basic network
1155 QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
1156 connection between several network devices. These devices can be for
1157 example QEMU virtual Ethernet cards or virtual Host ethernet devices
1160 @subsection Using TAP network interfaces
1162 This is the standard way to connect QEMU to a real network. QEMU adds
1163 a virtual network device on your host (called @code{tapN}), and you
1164 can then configure it as if it was a real ethernet card.
1166 @subsubsection Linux host
1168 As an example, you can download the @file{linux-test-xxx.tar.gz}
1169 archive and copy the script @file{qemu-ifup} in @file{/etc} and
1170 configure properly @code{sudo} so that the command @code{ifconfig}
1171 contained in @file{qemu-ifup} can be executed as root. You must verify
1172 that your host kernel supports the TAP network interfaces: the
1173 device @file{/dev/net/tun} must be present.
1175 See @ref{sec_invocation} to have examples of command lines using the
1176 TAP network interfaces.
1178 @subsubsection Windows host
1180 There is a virtual ethernet driver for Windows 2000/XP systems, called
1181 TAP-Win32. But it is not included in standard QEMU for Windows,
1182 so you will need to get it separately. It is part of OpenVPN package,
1183 so download OpenVPN from : @url{http://openvpn.net/}.
1185 @subsection Using the user mode network stack
1187 By using the option @option{-net user} (default configuration if no
1188 @option{-net} option is specified), QEMU uses a completely user mode
1189 network stack (you don't need root privilege to use the virtual
1190 network). The virtual network configuration is the following:
1194 QEMU VLAN <------> Firewall/DHCP server <-----> Internet
1197 ----> DNS server (10.0.2.3)
1199 ----> SMB server (10.0.2.4)
1202 The QEMU VM behaves as if it was behind a firewall which blocks all
1203 incoming connections. You can use a DHCP client to automatically
1204 configure the network in the QEMU VM. The DHCP server assign addresses
1205 to the hosts starting from 10.0.2.15.
1207 In order to check that the user mode network is working, you can ping
1208 the address 10.0.2.2 and verify that you got an address in the range
1209 10.0.2.x from the QEMU virtual DHCP server.
1211 Note that ICMP traffic in general does not work with user mode networking.
1212 @code{ping}, aka. ICMP echo, to the local router (10.0.2.2) shall work,
1213 however. If you're using QEMU on Linux >= 3.0, it can use unprivileged ICMP
1214 ping sockets to allow @code{ping} to the Internet. The host admin has to set
1215 the ping_group_range in order to grant access to those sockets. To allow ping
1216 for GID 100 (usually users group):
1219 echo 100 100 > /proc/sys/net/ipv4/ping_group_range
1222 When using the built-in TFTP server, the router is also the TFTP
1225 When using the @option{-redir} option, TCP or UDP connections can be
1226 redirected from the host to the guest. It allows for example to
1227 redirect X11, telnet or SSH connections.
1229 @subsection Connecting VLANs between QEMU instances
1231 Using the @option{-net socket} option, it is possible to make VLANs
1232 that span several QEMU instances. See @ref{sec_invocation} to have a
1235 @node pcsys_other_devs
1236 @section Other Devices
1238 @subsection Inter-VM Shared Memory device
1240 With KVM enabled on a Linux host, a shared memory device is available. Guests
1241 map a POSIX shared memory region into the guest as a PCI device that enables
1242 zero-copy communication to the application level of the guests. The basic
1246 qemu-system-i386 -device ivshmem,size=<size in format accepted by -m>[,shm=<shm name>]
1249 If desired, interrupts can be sent between guest VMs accessing the same shared
1250 memory region. Interrupt support requires using a shared memory server and
1251 using a chardev socket to connect to it. The code for the shared memory server
1252 is qemu.git/contrib/ivshmem-server. An example syntax when using the shared
1256 qemu-system-i386 -device ivshmem,size=<size in format accepted by -m>[,chardev=<id>]
1257 [,msi=on][,ioeventfd=on][,vectors=n][,role=peer|master]
1258 qemu-system-i386 -chardev socket,path=<path>,id=<id>
1261 When using the server, the guest will be assigned a VM ID (>=0) that allows guests
1262 using the same server to communicate via interrupts. Guests can read their
1263 VM ID from a device register (see example code). Since receiving the shared
1264 memory region from the server is asynchronous, there is a (small) chance the
1265 guest may boot before the shared memory is attached. To allow an application
1266 to ensure shared memory is attached, the VM ID register will return -1 (an
1267 invalid VM ID) until the memory is attached. Once the shared memory is
1268 attached, the VM ID will return the guest's valid VM ID. With these semantics,
1269 the guest application can check to ensure the shared memory is attached to the
1270 guest before proceeding.
1272 The @option{role} argument can be set to either master or peer and will affect
1273 how the shared memory is migrated. With @option{role=master}, the guest will
1274 copy the shared memory on migration to the destination host. With
1275 @option{role=peer}, the guest will not be able to migrate with the device attached.
1276 With the @option{peer} case, the device should be detached and then reattached
1277 after migration using the PCI hotplug support.
1279 @node direct_linux_boot
1280 @section Direct Linux Boot
1282 This section explains how to launch a Linux kernel inside QEMU without
1283 having to make a full bootable image. It is very useful for fast Linux
1288 qemu-system-i386 -kernel arch/i386/boot/bzImage -hda root-2.4.20.img -append "root=/dev/hda"
1291 Use @option{-kernel} to provide the Linux kernel image and
1292 @option{-append} to give the kernel command line arguments. The
1293 @option{-initrd} option can be used to provide an INITRD image.
1295 When using the direct Linux boot, a disk image for the first hard disk
1296 @file{hda} is required because its boot sector is used to launch the
1299 If you do not need graphical output, you can disable it and redirect
1300 the virtual serial port and the QEMU monitor to the console with the
1301 @option{-nographic} option. The typical command line is:
1303 qemu-system-i386 -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1304 -append "root=/dev/hda console=ttyS0" -nographic
1307 Use @key{Ctrl-a c} to switch between the serial console and the
1308 monitor (@pxref{pcsys_keys}).
1311 @section USB emulation
1313 QEMU emulates a PCI UHCI USB controller. You can virtually plug
1314 virtual USB devices or real host USB devices (experimental, works only
1315 on Linux hosts). QEMU will automatically create and connect virtual USB hubs
1316 as necessary to connect multiple USB devices.
1320 * host_usb_devices::
1323 @subsection Connecting USB devices
1325 USB devices can be connected with the @option{-usbdevice} commandline option
1326 or the @code{usb_add} monitor command. Available devices are:
1330 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1332 Pointer device that uses absolute coordinates (like a touchscreen).
1333 This means QEMU is able to report the mouse position without having
1334 to grab the mouse. Also overrides the PS/2 mouse emulation when activated.
1335 @item disk:@var{file}
1336 Mass storage device based on @var{file} (@pxref{disk_images})
1337 @item host:@var{bus.addr}
1338 Pass through the host device identified by @var{bus.addr}
1340 @item host:@var{vendor_id:product_id}
1341 Pass through the host device identified by @var{vendor_id:product_id}
1344 Virtual Wacom PenPartner tablet. This device is similar to the @code{tablet}
1345 above but it can be used with the tslib library because in addition to touch
1346 coordinates it reports touch pressure.
1348 Standard USB keyboard. Will override the PS/2 keyboard (if present).
1349 @item serial:[vendorid=@var{vendor_id}][,product_id=@var{product_id}]:@var{dev}
1350 Serial converter. This emulates an FTDI FT232BM chip connected to host character
1351 device @var{dev}. The available character devices are the same as for the
1352 @code{-serial} option. The @code{vendorid} and @code{productid} options can be
1353 used to override the default 0403:6001. For instance,
1355 usb_add serial:productid=FA00:tcp:192.168.0.2:4444
1357 will connect to tcp port 4444 of ip 192.168.0.2, and plug that to the virtual
1358 serial converter, faking a Matrix Orbital LCD Display (USB ID 0403:FA00).
1360 Braille device. This will use BrlAPI to display the braille output on a real
1362 @item net:@var{options}
1363 Network adapter that supports CDC ethernet and RNDIS protocols. @var{options}
1364 specifies NIC options as with @code{-net nic,}@var{options} (see description).
1365 For instance, user-mode networking can be used with
1367 qemu-system-i386 [...OPTIONS...] -net user,vlan=0 -usbdevice net:vlan=0
1369 Currently this cannot be used in machines that support PCI NICs.
1370 @item bt[:@var{hci-type}]
1371 Bluetooth dongle whose type is specified in the same format as with
1372 the @option{-bt hci} option, @pxref{bt-hcis,,allowed HCI types}. If
1373 no type is given, the HCI logic corresponds to @code{-bt hci,vlan=0}.
1374 This USB device implements the USB Transport Layer of HCI. Example
1377 qemu-system-i386 [...OPTIONS...] -usbdevice bt:hci,vlan=3 -bt device:keyboard,vlan=3
1381 @node host_usb_devices
1382 @subsection Using host USB devices on a Linux host
1384 WARNING: this is an experimental feature. QEMU will slow down when
1385 using it. USB devices requiring real time streaming (i.e. USB Video
1386 Cameras) are not supported yet.
1389 @item If you use an early Linux 2.4 kernel, verify that no Linux driver
1390 is actually using the USB device. A simple way to do that is simply to
1391 disable the corresponding kernel module by renaming it from @file{mydriver.o}
1392 to @file{mydriver.o.disabled}.
1394 @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
1400 @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:
1402 chown -R myuid /proc/bus/usb
1405 @item Launch QEMU and do in the monitor:
1408 Device 1.2, speed 480 Mb/s
1409 Class 00: USB device 1234:5678, USB DISK
1411 You should see the list of the devices you can use (Never try to use
1412 hubs, it won't work).
1414 @item Add the device in QEMU by using:
1416 usb_add host:1234:5678
1419 Normally the guest OS should report that a new USB device is
1420 plugged. You can use the option @option{-usbdevice} to do the same.
1422 @item Now you can try to use the host USB device in QEMU.
1426 When relaunching QEMU, you may have to unplug and plug again the USB
1427 device to make it work again (this is a bug).
1430 @section VNC security
1432 The VNC server capability provides access to the graphical console
1433 of the guest VM across the network. This has a number of security
1434 considerations depending on the deployment scenarios.
1438 * vnc_sec_password::
1439 * vnc_sec_certificate::
1440 * vnc_sec_certificate_verify::
1441 * vnc_sec_certificate_pw::
1443 * vnc_sec_certificate_sasl::
1444 * vnc_generate_cert::
1448 @subsection Without passwords
1450 The simplest VNC server setup does not include any form of authentication.
1451 For this setup it is recommended to restrict it to listen on a UNIX domain
1452 socket only. For example
1455 qemu-system-i386 [...OPTIONS...] -vnc unix:/home/joebloggs/.qemu-myvm-vnc
1458 This ensures that only users on local box with read/write access to that
1459 path can access the VNC server. To securely access the VNC server from a
1460 remote machine, a combination of netcat+ssh can be used to provide a secure
1463 @node vnc_sec_password
1464 @subsection With passwords
1466 The VNC protocol has limited support for password based authentication. Since
1467 the protocol limits passwords to 8 characters it should not be considered
1468 to provide high security. The password can be fairly easily brute-forced by
1469 a client making repeat connections. For this reason, a VNC server using password
1470 authentication should be restricted to only listen on the loopback interface
1471 or UNIX domain sockets. Password authentication is not supported when operating
1472 in FIPS 140-2 compliance mode as it requires the use of the DES cipher. Password
1473 authentication is requested with the @code{password} option, and then once QEMU
1474 is running the password is set with the monitor. Until the monitor is used to
1475 set the password all clients will be rejected.
1478 qemu-system-i386 [...OPTIONS...] -vnc :1,password -monitor stdio
1479 (qemu) change vnc password
1484 @node vnc_sec_certificate
1485 @subsection With x509 certificates
1487 The QEMU VNC server also implements the VeNCrypt extension allowing use of
1488 TLS for encryption of the session, and x509 certificates for authentication.
1489 The use of x509 certificates is strongly recommended, because TLS on its
1490 own is susceptible to man-in-the-middle attacks. Basic x509 certificate
1491 support provides a secure session, but no authentication. This allows any
1492 client to connect, and provides an encrypted session.
1495 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509=/etc/pki/qemu -monitor stdio
1498 In the above example @code{/etc/pki/qemu} should contain at least three files,
1499 @code{ca-cert.pem}, @code{server-cert.pem} and @code{server-key.pem}. Unprivileged
1500 users will want to use a private directory, for example @code{$HOME/.pki/qemu}.
1501 NB the @code{server-key.pem} file should be protected with file mode 0600 to
1502 only be readable by the user owning it.
1504 @node vnc_sec_certificate_verify
1505 @subsection With x509 certificates and client verification
1507 Certificates can also provide a means to authenticate the client connecting.
1508 The server will request that the client provide a certificate, which it will
1509 then validate against the CA certificate. This is a good choice if deploying
1510 in an environment with a private internal certificate authority.
1513 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509verify=/etc/pki/qemu -monitor stdio
1517 @node vnc_sec_certificate_pw
1518 @subsection With x509 certificates, client verification and passwords
1520 Finally, the previous method can be combined with VNC password authentication
1521 to provide two layers of authentication for clients.
1524 qemu-system-i386 [...OPTIONS...] -vnc :1,password,tls,x509verify=/etc/pki/qemu -monitor stdio
1525 (qemu) change vnc password
1532 @subsection With SASL authentication
1534 The SASL authentication method is a VNC extension, that provides an
1535 easily extendable, pluggable authentication method. This allows for
1536 integration with a wide range of authentication mechanisms, such as
1537 PAM, GSSAPI/Kerberos, LDAP, SQL databases, one-time keys and more.
1538 The strength of the authentication depends on the exact mechanism
1539 configured. If the chosen mechanism also provides a SSF layer, then
1540 it will encrypt the datastream as well.
1542 Refer to the later docs on how to choose the exact SASL mechanism
1543 used for authentication, but assuming use of one supporting SSF,
1544 then QEMU can be launched with:
1547 qemu-system-i386 [...OPTIONS...] -vnc :1,sasl -monitor stdio
1550 @node vnc_sec_certificate_sasl
1551 @subsection With x509 certificates and SASL authentication
1553 If the desired SASL authentication mechanism does not supported
1554 SSF layers, then it is strongly advised to run it in combination
1555 with TLS and x509 certificates. This provides securely encrypted
1556 data stream, avoiding risk of compromising of the security
1557 credentials. This can be enabled, by combining the 'sasl' option
1558 with the aforementioned TLS + x509 options:
1561 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509,sasl -monitor stdio
1565 @node vnc_generate_cert
1566 @subsection Generating certificates for VNC
1568 The GNU TLS packages provides a command called @code{certtool} which can
1569 be used to generate certificates and keys in PEM format. At a minimum it
1570 is necessary to setup a certificate authority, and issue certificates to
1571 each server. If using certificates for authentication, then each client
1572 will also need to be issued a certificate. The recommendation is for the
1573 server to keep its certificates in either @code{/etc/pki/qemu} or for
1574 unprivileged users in @code{$HOME/.pki/qemu}.
1578 * vnc_generate_server::
1579 * vnc_generate_client::
1581 @node vnc_generate_ca
1582 @subsubsection Setup the Certificate Authority
1584 This step only needs to be performed once per organization / organizational
1585 unit. First the CA needs a private key. This key must be kept VERY secret
1586 and secure. If this key is compromised the entire trust chain of the certificates
1587 issued with it is lost.
1590 # certtool --generate-privkey > ca-key.pem
1593 A CA needs to have a public certificate. For simplicity it can be a self-signed
1594 certificate, or one issue by a commercial certificate issuing authority. To
1595 generate a self-signed certificate requires one core piece of information, the
1596 name of the organization.
1599 # cat > ca.info <<EOF
1600 cn = Name of your organization
1604 # certtool --generate-self-signed \
1605 --load-privkey ca-key.pem
1606 --template ca.info \
1607 --outfile ca-cert.pem
1610 The @code{ca-cert.pem} file should be copied to all servers and clients wishing to utilize
1611 TLS support in the VNC server. The @code{ca-key.pem} must not be disclosed/copied at all.
1613 @node vnc_generate_server
1614 @subsubsection Issuing server certificates
1616 Each server (or host) needs to be issued with a key and certificate. When connecting
1617 the certificate is sent to the client which validates it against the CA certificate.
1618 The core piece of information for a server certificate is the hostname. This should
1619 be the fully qualified hostname that the client will connect with, since the client
1620 will typically also verify the hostname in the certificate. On the host holding the
1621 secure CA private key:
1624 # cat > server.info <<EOF
1625 organization = Name of your organization
1626 cn = server.foo.example.com
1631 # certtool --generate-privkey > server-key.pem
1632 # certtool --generate-certificate \
1633 --load-ca-certificate ca-cert.pem \
1634 --load-ca-privkey ca-key.pem \
1635 --load-privkey server server-key.pem \
1636 --template server.info \
1637 --outfile server-cert.pem
1640 The @code{server-key.pem} and @code{server-cert.pem} files should now be securely copied
1641 to the server for which they were generated. The @code{server-key.pem} is security
1642 sensitive and should be kept protected with file mode 0600 to prevent disclosure.
1644 @node vnc_generate_client
1645 @subsubsection Issuing client certificates
1647 If the QEMU VNC server is to use the @code{x509verify} option to validate client
1648 certificates as its authentication mechanism, each client also needs to be issued
1649 a certificate. The client certificate contains enough metadata to uniquely identify
1650 the client, typically organization, state, city, building, etc. On the host holding
1651 the secure CA private key:
1654 # cat > client.info <<EOF
1658 organiazation = Name of your organization
1659 cn = client.foo.example.com
1664 # certtool --generate-privkey > client-key.pem
1665 # certtool --generate-certificate \
1666 --load-ca-certificate ca-cert.pem \
1667 --load-ca-privkey ca-key.pem \
1668 --load-privkey client-key.pem \
1669 --template client.info \
1670 --outfile client-cert.pem
1673 The @code{client-key.pem} and @code{client-cert.pem} files should now be securely
1674 copied to the client for which they were generated.
1677 @node vnc_setup_sasl
1679 @subsection Configuring SASL mechanisms
1681 The following documentation assumes use of the Cyrus SASL implementation on a
1682 Linux host, but the principals should apply to any other SASL impl. When SASL
1683 is enabled, the mechanism configuration will be loaded from system default
1684 SASL service config /etc/sasl2/qemu.conf. If running QEMU as an
1685 unprivileged user, an environment variable SASL_CONF_PATH can be used
1686 to make it search alternate locations for the service config.
1688 The default configuration might contain
1691 mech_list: digest-md5
1692 sasldb_path: /etc/qemu/passwd.db
1695 This says to use the 'Digest MD5' mechanism, which is similar to the HTTP
1696 Digest-MD5 mechanism. The list of valid usernames & passwords is maintained
1697 in the /etc/qemu/passwd.db file, and can be updated using the saslpasswd2
1698 command. While this mechanism is easy to configure and use, it is not
1699 considered secure by modern standards, so only suitable for developers /
1702 A more serious deployment might use Kerberos, which is done with the 'gssapi'
1707 keytab: /etc/qemu/krb5.tab
1710 For this to work the administrator of your KDC must generate a Kerberos
1711 principal for the server, with a name of 'qemu/somehost.example.com@@EXAMPLE.COM'
1712 replacing 'somehost.example.com' with the fully qualified host name of the
1713 machine running QEMU, and 'EXAMPLE.COM' with the Kerberos Realm.
1715 Other configurations will be left as an exercise for the reader. It should
1716 be noted that only Digest-MD5 and GSSAPI provides a SSF layer for data
1717 encryption. For all other mechanisms, VNC should always be configured to
1718 use TLS and x509 certificates to protect security credentials from snooping.
1723 QEMU has a primitive support to work with gdb, so that you can do
1724 'Ctrl-C' while the virtual machine is running and inspect its state.
1726 In order to use gdb, launch QEMU with the '-s' option. It will wait for a
1729 qemu-system-i386 -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1730 -append "root=/dev/hda"
1731 Connected to host network interface: tun0
1732 Waiting gdb connection on port 1234
1735 Then launch gdb on the 'vmlinux' executable:
1740 In gdb, connect to QEMU:
1742 (gdb) target remote localhost:1234
1745 Then you can use gdb normally. For example, type 'c' to launch the kernel:
1750 Here are some useful tips in order to use gdb on system code:
1754 Use @code{info reg} to display all the CPU registers.
1756 Use @code{x/10i $eip} to display the code at the PC position.
1758 Use @code{set architecture i8086} to dump 16 bit code. Then use
1759 @code{x/10i $cs*16+$eip} to dump the code at the PC position.
1762 Advanced debugging options:
1764 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:
1766 @item maintenance packet qqemu.sstepbits
1768 This will display the MASK bits used to control the single stepping IE:
1770 (gdb) maintenance packet qqemu.sstepbits
1771 sending: "qqemu.sstepbits"
1772 received: "ENABLE=1,NOIRQ=2,NOTIMER=4"
1774 @item maintenance packet qqemu.sstep
1776 This will display the current value of the mask used when single stepping IE:
1778 (gdb) maintenance packet qqemu.sstep
1779 sending: "qqemu.sstep"
1782 @item maintenance packet Qqemu.sstep=HEX_VALUE
1784 This will change the single step mask, so if wanted to enable IRQs on the single step, but not timers, you would use:
1786 (gdb) maintenance packet Qqemu.sstep=0x5
1787 sending: "qemu.sstep=0x5"
1792 @node pcsys_os_specific
1793 @section Target OS specific information
1797 To have access to SVGA graphic modes under X11, use the @code{vesa} or
1798 the @code{cirrus} X11 driver. For optimal performances, use 16 bit
1799 color depth in the guest and the host OS.
1801 When using a 2.6 guest Linux kernel, you should add the option
1802 @code{clock=pit} on the kernel command line because the 2.6 Linux
1803 kernels make very strict real time clock checks by default that QEMU
1804 cannot simulate exactly.
1806 When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
1807 not activated because QEMU is slower with this patch. The QEMU
1808 Accelerator Module is also much slower in this case. Earlier Fedora
1809 Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporate this
1810 patch by default. Newer kernels don't have it.
1814 If you have a slow host, using Windows 95 is better as it gives the
1815 best speed. Windows 2000 is also a good choice.
1817 @subsubsection SVGA graphic modes support
1819 QEMU emulates a Cirrus Logic GD5446 Video
1820 card. All Windows versions starting from Windows 95 should recognize
1821 and use this graphic card. For optimal performances, use 16 bit color
1822 depth in the guest and the host OS.
1824 If you are using Windows XP as guest OS and if you want to use high
1825 resolution modes which the Cirrus Logic BIOS does not support (i.e. >=
1826 1280x1024x16), then you should use the VESA VBE virtual graphic card
1827 (option @option{-std-vga}).
1829 @subsubsection CPU usage reduction
1831 Windows 9x does not correctly use the CPU HLT
1832 instruction. The result is that it takes host CPU cycles even when
1833 idle. You can install the utility from
1834 @url{http://www.user.cityline.ru/~maxamn/amnhltm.zip} to solve this
1835 problem. Note that no such tool is needed for NT, 2000 or XP.
1837 @subsubsection Windows 2000 disk full problem
1839 Windows 2000 has a bug which gives a disk full problem during its
1840 installation. When installing it, use the @option{-win2k-hack} QEMU
1841 option to enable a specific workaround. After Windows 2000 is
1842 installed, you no longer need this option (this option slows down the
1845 @subsubsection Windows 2000 shutdown
1847 Windows 2000 cannot automatically shutdown in QEMU although Windows 98
1848 can. It comes from the fact that Windows 2000 does not automatically
1849 use the APM driver provided by the BIOS.
1851 In order to correct that, do the following (thanks to Struan
1852 Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
1853 Add/Troubleshoot a device => Add a new device & Next => No, select the
1854 hardware from a list & Next => NT Apm/Legacy Support & Next => Next
1855 (again) a few times. Now the driver is installed and Windows 2000 now
1856 correctly instructs QEMU to shutdown at the appropriate moment.
1858 @subsubsection Share a directory between Unix and Windows
1860 See @ref{sec_invocation} about the help of the option @option{-smb}.
1862 @subsubsection Windows XP security problem
1864 Some releases of Windows XP install correctly but give a security
1867 A problem is preventing Windows from accurately checking the
1868 license for this computer. Error code: 0x800703e6.
1871 The workaround is to install a service pack for XP after a boot in safe
1872 mode. Then reboot, and the problem should go away. Since there is no
1873 network while in safe mode, its recommended to download the full
1874 installation of SP1 or SP2 and transfer that via an ISO or using the
1875 vvfat block device ("-hdb fat:directory_which_holds_the_SP").
1877 @subsection MS-DOS and FreeDOS
1879 @subsubsection CPU usage reduction
1881 DOS does not correctly use the CPU HLT instruction. The result is that
1882 it takes host CPU cycles even when idle. You can install the utility
1883 from @url{http://www.vmware.com/software/dosidle210.zip} to solve this
1886 @node QEMU System emulator for non PC targets
1887 @chapter QEMU System emulator for non PC targets
1889 QEMU is a generic emulator and it emulates many non PC
1890 machines. Most of the options are similar to the PC emulator. The
1891 differences are mentioned in the following sections.
1894 * PowerPC System emulator::
1895 * Sparc32 System emulator::
1896 * Sparc64 System emulator::
1897 * MIPS System emulator::
1898 * ARM System emulator::
1899 * ColdFire System emulator::
1900 * Cris System emulator::
1901 * Microblaze System emulator::
1902 * SH4 System emulator::
1903 * Xtensa System emulator::
1906 @node PowerPC System emulator
1907 @section PowerPC System emulator
1908 @cindex system emulation (PowerPC)
1910 Use the executable @file{qemu-system-ppc} to simulate a complete PREP
1911 or PowerMac PowerPC system.
1913 QEMU emulates the following PowerMac peripherals:
1917 UniNorth or Grackle PCI Bridge
1919 PCI VGA compatible card with VESA Bochs Extensions
1921 2 PMAC IDE interfaces with hard disk and CD-ROM support
1927 VIA-CUDA with ADB keyboard and mouse.
1930 QEMU emulates the following PREP peripherals:
1936 PCI VGA compatible card with VESA Bochs Extensions
1938 2 IDE interfaces with hard disk and CD-ROM support
1942 NE2000 network adapters
1946 PREP Non Volatile RAM
1948 PC compatible keyboard and mouse.
1951 QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS.
1953 Since version 0.9.1, QEMU uses OpenBIOS @url{http://www.openbios.org/}
1954 for the g3beige and mac99 PowerMac machines. OpenBIOS is a free (GPL
1955 v2) portable firmware implementation. The goal is to implement a 100%
1956 IEEE 1275-1994 (referred to as Open Firmware) compliant firmware.
1958 @c man begin OPTIONS
1960 The following options are specific to the PowerPC emulation:
1964 @item -g @var{W}x@var{H}[x@var{DEPTH}]
1966 Set the initial VGA graphic mode. The default is 800x600x32.
1968 @item -prom-env @var{string}
1970 Set OpenBIOS variables in NVRAM, for example:
1973 qemu-system-ppc -prom-env 'auto-boot?=false' \
1974 -prom-env 'boot-device=hd:2,\yaboot' \
1975 -prom-env 'boot-args=conf=hd:2,\yaboot.conf'
1978 These variables are not used by Open Hack'Ware.
1984 @node Sparc32 System emulator
1985 @section Sparc32 System emulator
1986 @cindex system emulation (Sparc32)
1988 Use the executable @file{qemu-system-sparc} to simulate the following
1989 Sun4m architecture machines:
2004 SPARCstation Voyager
2011 The emulation is somewhat complete. SMP up to 16 CPUs is supported,
2012 but Linux limits the number of usable CPUs to 4.
2014 QEMU emulates the following sun4m peripherals:
2020 TCX or cgthree Frame buffer
2022 Lance (Am7990) Ethernet
2024 Non Volatile RAM M48T02/M48T08
2026 Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
2027 and power/reset logic
2029 ESP SCSI controller with hard disk and CD-ROM support
2031 Floppy drive (not on SS-600MP)
2033 CS4231 sound device (only on SS-5, not working yet)
2036 The number of peripherals is fixed in the architecture. Maximum
2037 memory size depends on the machine type, for SS-5 it is 256MB and for
2040 Since version 0.8.2, QEMU uses OpenBIOS
2041 @url{http://www.openbios.org/}. OpenBIOS is a free (GPL v2) portable
2042 firmware implementation. The goal is to implement a 100% IEEE
2043 1275-1994 (referred to as Open Firmware) compliant firmware.
2045 A sample Linux 2.6 series kernel and ram disk image are available on
2046 the QEMU web site. There are still issues with NetBSD and OpenBSD, but
2047 some kernel versions work. Please note that currently older Solaris kernels
2048 don't work probably due to interface issues between OpenBIOS and
2051 @c man begin OPTIONS
2053 The following options are specific to the Sparc32 emulation:
2057 @item -g @var{W}x@var{H}x[x@var{DEPTH}]
2059 Set the initial graphics mode. For TCX, the default is 1024x768x8 with the
2060 option of 1024x768x24. For cgthree, the default is 1024x768x8 with the option
2061 of 1152x900x8 for people who wish to use OBP.
2063 @item -prom-env @var{string}
2065 Set OpenBIOS variables in NVRAM, for example:
2068 qemu-system-sparc -prom-env 'auto-boot?=false' \
2069 -prom-env 'boot-device=sd(0,2,0):d' -prom-env 'boot-args=linux single'
2072 @item -M [SS-4|SS-5|SS-10|SS-20|SS-600MP|LX|Voyager|SPARCClassic] [|SPARCbook]
2074 Set the emulated machine type. Default is SS-5.
2080 @node Sparc64 System emulator
2081 @section Sparc64 System emulator
2082 @cindex system emulation (Sparc64)
2084 Use the executable @file{qemu-system-sparc64} to simulate a Sun4u
2085 (UltraSPARC PC-like machine), Sun4v (T1 PC-like machine), or generic
2086 Niagara (T1) machine. The emulator is not usable for anything yet, but
2087 it can launch some kernels.
2089 QEMU emulates the following peripherals:
2093 UltraSparc IIi APB PCI Bridge
2095 PCI VGA compatible card with VESA Bochs Extensions
2097 PS/2 mouse and keyboard
2099 Non Volatile RAM M48T59
2101 PC-compatible serial ports
2103 2 PCI IDE interfaces with hard disk and CD-ROM support
2108 @c man begin OPTIONS
2110 The following options are specific to the Sparc64 emulation:
2114 @item -prom-env @var{string}
2116 Set OpenBIOS variables in NVRAM, for example:
2119 qemu-system-sparc64 -prom-env 'auto-boot?=false'
2122 @item -M [sun4u|sun4v|Niagara]
2124 Set the emulated machine type. The default is sun4u.
2130 @node MIPS System emulator
2131 @section MIPS System emulator
2132 @cindex system emulation (MIPS)
2134 Four executables cover simulation of 32 and 64-bit MIPS systems in
2135 both endian options, @file{qemu-system-mips}, @file{qemu-system-mipsel}
2136 @file{qemu-system-mips64} and @file{qemu-system-mips64el}.
2137 Five different machine types are emulated:
2141 A generic ISA PC-like machine "mips"
2143 The MIPS Malta prototype board "malta"
2145 An ACER Pica "pica61". This machine needs the 64-bit emulator.
2147 MIPS emulator pseudo board "mipssim"
2149 A MIPS Magnum R4000 machine "magnum". This machine needs the 64-bit emulator.
2152 The generic emulation is supported by Debian 'Etch' and is able to
2153 install Debian into a virtual disk image. The following devices are
2158 A range of MIPS CPUs, default is the 24Kf
2160 PC style serial port
2167 The Malta emulation supports the following devices:
2171 Core board with MIPS 24Kf CPU and Galileo system controller
2173 PIIX4 PCI/USB/SMbus controller
2175 The Multi-I/O chip's serial device
2177 PCI network cards (PCnet32 and others)
2179 Malta FPGA serial device
2181 Cirrus (default) or any other PCI VGA graphics card
2184 The ACER Pica emulation supports:
2190 PC-style IRQ and DMA controllers
2197 The mipssim pseudo board emulation provides an environment similar
2198 to what the proprietary MIPS emulator uses for running Linux.
2203 A range of MIPS CPUs, default is the 24Kf
2205 PC style serial port
2207 MIPSnet network emulation
2210 The MIPS Magnum R4000 emulation supports:
2216 PC-style IRQ controller
2226 @node ARM System emulator
2227 @section ARM System emulator
2228 @cindex system emulation (ARM)
2230 Use the executable @file{qemu-system-arm} to simulate a ARM
2231 machine. The ARM Integrator/CP board is emulated with the following
2236 ARM926E, ARM1026E, ARM946E, ARM1136 or Cortex-A8 CPU
2240 SMC 91c111 Ethernet adapter
2242 PL110 LCD controller
2244 PL050 KMI with PS/2 keyboard and mouse.
2246 PL181 MultiMedia Card Interface with SD card.
2249 The ARM Versatile baseboard is emulated with the following devices:
2253 ARM926E, ARM1136 or Cortex-A8 CPU
2255 PL190 Vectored Interrupt Controller
2259 SMC 91c111 Ethernet adapter
2261 PL110 LCD controller
2263 PL050 KMI with PS/2 keyboard and mouse.
2265 PCI host bridge. Note the emulated PCI bridge only provides access to
2266 PCI memory space. It does not provide access to PCI IO space.
2267 This means some devices (eg. ne2k_pci NIC) are not usable, and others
2268 (eg. rtl8139 NIC) are only usable when the guest drivers use the memory
2269 mapped control registers.
2271 PCI OHCI USB controller.
2273 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices.
2275 PL181 MultiMedia Card Interface with SD card.
2278 Several variants of the ARM RealView baseboard are emulated,
2279 including the EB, PB-A8 and PBX-A9. Due to interactions with the
2280 bootloader, only certain Linux kernel configurations work out
2281 of the box on these boards.
2283 Kernels for the PB-A8 board should have CONFIG_REALVIEW_HIGH_PHYS_OFFSET
2284 enabled in the kernel, and expect 512M RAM. Kernels for The PBX-A9 board
2285 should have CONFIG_SPARSEMEM enabled, CONFIG_REALVIEW_HIGH_PHYS_OFFSET
2286 disabled and expect 1024M RAM.
2288 The following devices are emulated:
2292 ARM926E, ARM1136, ARM11MPCore, Cortex-A8 or Cortex-A9 MPCore CPU
2294 ARM AMBA Generic/Distributed Interrupt Controller
2298 SMC 91c111 or SMSC LAN9118 Ethernet adapter
2300 PL110 LCD controller
2302 PL050 KMI with PS/2 keyboard and mouse
2306 PCI OHCI USB controller
2308 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices
2310 PL181 MultiMedia Card Interface with SD card.
2313 The XScale-based clamshell PDA models ("Spitz", "Akita", "Borzoi"
2314 and "Terrier") emulation includes the following peripherals:
2318 Intel PXA270 System-on-chip (ARM V5TE core)
2322 IBM/Hitachi DSCM microdrive in a PXA PCMCIA slot - not in "Akita"
2324 On-chip OHCI USB controller
2326 On-chip LCD controller
2328 On-chip Real Time Clock
2330 TI ADS7846 touchscreen controller on SSP bus
2332 Maxim MAX1111 analog-digital converter on I@math{^2}C bus
2334 GPIO-connected keyboard controller and LEDs
2336 Secure Digital card connected to PXA MMC/SD host
2340 WM8750 audio CODEC on I@math{^2}C and I@math{^2}S busses
2343 The Palm Tungsten|E PDA (codename "Cheetah") emulation includes the
2348 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
2350 ROM and RAM memories (ROM firmware image can be loaded with -option-rom)
2352 On-chip LCD controller
2354 On-chip Real Time Clock
2356 TI TSC2102i touchscreen controller / analog-digital converter / Audio
2357 CODEC, connected through MicroWire and I@math{^2}S busses
2359 GPIO-connected matrix keypad
2361 Secure Digital card connected to OMAP MMC/SD host
2366 Nokia N800 and N810 internet tablets (known also as RX-34 and RX-44 / 48)
2367 emulation supports the following elements:
2371 Texas Instruments OMAP2420 System-on-chip (ARM 1136 core)
2373 RAM and non-volatile OneNAND Flash memories
2375 Display connected to EPSON remote framebuffer chip and OMAP on-chip
2376 display controller and a LS041y3 MIPI DBI-C controller
2378 TI TSC2301 (in N800) and TI TSC2005 (in N810) touchscreen controllers
2379 driven through SPI bus
2381 National Semiconductor LM8323-controlled qwerty keyboard driven
2382 through I@math{^2}C bus
2384 Secure Digital card connected to OMAP MMC/SD host
2386 Three OMAP on-chip UARTs and on-chip STI debugging console
2388 A Bluetooth(R) transceiver and HCI connected to an UART
2390 Mentor Graphics "Inventra" dual-role USB controller embedded in a TI
2391 TUSB6010 chip - only USB host mode is supported
2393 TI TMP105 temperature sensor driven through I@math{^2}C bus
2395 TI TWL92230C power management companion with an RTC on I@math{^2}C bus
2397 Nokia RETU and TAHVO multi-purpose chips with an RTC, connected
2401 The Luminary Micro Stellaris LM3S811EVB emulation includes the following
2408 64k Flash and 8k SRAM.
2410 Timers, UARTs, ADC and I@math{^2}C interface.
2412 OSRAM Pictiva 96x16 OLED with SSD0303 controller on I@math{^2}C bus.
2415 The Luminary Micro Stellaris LM3S6965EVB emulation includes the following
2422 256k Flash and 64k SRAM.
2424 Timers, UARTs, ADC, I@math{^2}C and SSI interfaces.
2426 OSRAM Pictiva 128x64 OLED with SSD0323 controller connected via SSI.
2429 The Freecom MusicPal internet radio emulation includes the following
2434 Marvell MV88W8618 ARM core.
2436 32 MB RAM, 256 KB SRAM, 8 MB flash.
2440 MV88W8xx8 Ethernet controller
2442 MV88W8618 audio controller, WM8750 CODEC and mixer
2444 128×64 display with brightness control
2446 2 buttons, 2 navigation wheels with button function
2449 The Siemens SX1 models v1 and v2 (default) basic emulation.
2450 The emulation includes the following elements:
2454 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
2456 ROM and RAM memories (ROM firmware image can be loaded with -pflash)
2458 1 Flash of 16MB and 1 Flash of 8MB
2462 On-chip LCD controller
2464 On-chip Real Time Clock
2466 Secure Digital card connected to OMAP MMC/SD host
2471 A Linux 2.6 test image is available on the QEMU web site. More
2472 information is available in the QEMU mailing-list archive.
2474 @c man begin OPTIONS
2476 The following options are specific to the ARM emulation:
2481 Enable semihosting syscall emulation.
2483 On ARM this implements the "Angel" interface.
2485 Note that this allows guest direct access to the host filesystem,
2486 so should only be used with trusted guest OS.
2490 @node ColdFire System emulator
2491 @section ColdFire System emulator
2492 @cindex system emulation (ColdFire)
2493 @cindex system emulation (M68K)
2495 Use the executable @file{qemu-system-m68k} to simulate a ColdFire machine.
2496 The emulator is able to boot a uClinux kernel.
2498 The M5208EVB emulation includes the following devices:
2502 MCF5208 ColdFire V2 Microprocessor (ISA A+ with EMAC).
2504 Three Two on-chip UARTs.
2506 Fast Ethernet Controller (FEC)
2509 The AN5206 emulation includes the following devices:
2513 MCF5206 ColdFire V2 Microprocessor.
2518 @c man begin OPTIONS
2520 The following options are specific to the ColdFire emulation:
2525 Enable semihosting syscall emulation.
2527 On M68K this implements the "ColdFire GDB" interface used by libgloss.
2529 Note that this allows guest direct access to the host filesystem,
2530 so should only be used with trusted guest OS.
2534 @node Cris System emulator
2535 @section Cris System emulator
2536 @cindex system emulation (Cris)
2540 @node Microblaze System emulator
2541 @section Microblaze System emulator
2542 @cindex system emulation (Microblaze)
2546 @node SH4 System emulator
2547 @section SH4 System emulator
2548 @cindex system emulation (SH4)
2552 @node Xtensa System emulator
2553 @section Xtensa System emulator
2554 @cindex system emulation (Xtensa)
2556 Two executables cover simulation of both Xtensa endian options,
2557 @file{qemu-system-xtensa} and @file{qemu-system-xtensaeb}.
2558 Two different machine types are emulated:
2562 Xtensa emulator pseudo board "sim"
2564 Avnet LX60/LX110/LX200 board
2567 The sim pseudo board emulation provides an environment similar
2568 to one provided by the proprietary Tensilica ISS.
2573 A range of Xtensa CPUs, default is the DC232B
2575 Console and filesystem access via semihosting calls
2578 The Avnet LX60/LX110/LX200 emulation supports:
2582 A range of Xtensa CPUs, default is the DC232B
2586 OpenCores 10/100 Mbps Ethernet MAC
2589 @c man begin OPTIONS
2591 The following options are specific to the Xtensa emulation:
2596 Enable semihosting syscall emulation.
2598 Xtensa semihosting provides basic file IO calls, such as open/read/write/seek/select.
2599 Tensilica baremetal libc for ISS and linux platform "sim" use this interface.
2601 Note that this allows guest direct access to the host filesystem,
2602 so should only be used with trusted guest OS.
2605 @node QEMU User space emulator
2606 @chapter QEMU User space emulator
2609 * Supported Operating Systems ::
2610 * Linux User space emulator::
2611 * BSD User space emulator ::
2614 @node Supported Operating Systems
2615 @section Supported Operating Systems
2617 The following OS are supported in user space emulation:
2621 Linux (referred as qemu-linux-user)
2623 BSD (referred as qemu-bsd-user)
2626 @node Linux User space emulator
2627 @section Linux User space emulator
2632 * Command line options::
2637 @subsection Quick Start
2639 In order to launch a Linux process, QEMU needs the process executable
2640 itself and all the target (x86) dynamic libraries used by it.
2644 @item On x86, you can just try to launch any process by using the native
2648 qemu-i386 -L / /bin/ls
2651 @code{-L /} tells that the x86 dynamic linker must be searched with a
2654 @item Since QEMU is also a linux process, you can launch QEMU with
2655 QEMU (NOTE: you can only do that if you compiled QEMU from the sources):
2658 qemu-i386 -L / qemu-i386 -L / /bin/ls
2661 @item On non x86 CPUs, you need first to download at least an x86 glibc
2662 (@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
2663 @code{LD_LIBRARY_PATH} is not set:
2666 unset LD_LIBRARY_PATH
2669 Then you can launch the precompiled @file{ls} x86 executable:
2672 qemu-i386 tests/i386/ls
2674 You can look at @file{scripts/qemu-binfmt-conf.sh} so that
2675 QEMU is automatically launched by the Linux kernel when you try to
2676 launch x86 executables. It requires the @code{binfmt_misc} module in the
2679 @item The x86 version of QEMU is also included. You can try weird things such as:
2681 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 \
2682 /usr/local/qemu-i386/bin/ls-i386
2688 @subsection Wine launch
2692 @item Ensure that you have a working QEMU with the x86 glibc
2693 distribution (see previous section). In order to verify it, you must be
2697 qemu-i386 /usr/local/qemu-i386/bin/ls-i386
2700 @item Download the binary x86 Wine install
2701 (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
2703 @item Configure Wine on your account. Look at the provided script
2704 @file{/usr/local/qemu-i386/@/bin/wine-conf.sh}. Your previous
2705 @code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
2707 @item Then you can try the example @file{putty.exe}:
2710 qemu-i386 /usr/local/qemu-i386/wine/bin/wine \
2711 /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
2716 @node Command line options
2717 @subsection Command line options
2720 usage: qemu-i386 [-h] [-d] [-L path] [-s size] [-cpu model] [-g port] [-B offset] [-R size] program [arguments...]
2727 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
2729 Set the x86 stack size in bytes (default=524288)
2731 Select CPU model (-cpu help for list and additional feature selection)
2732 @item -E @var{var}=@var{value}
2733 Set environment @var{var} to @var{value}.
2735 Remove @var{var} from the environment.
2737 Offset guest address by the specified number of bytes. This is useful when
2738 the address region required by guest applications is reserved on the host.
2739 This option is currently only supported on some hosts.
2741 Pre-allocate a guest virtual address space of the given size (in bytes).
2742 "G", "M", and "k" suffixes may be used when specifying the size.
2749 Activate logging of the specified items (use '-d help' for a list of log items)
2751 Act as if the host page size was 'pagesize' bytes
2753 Wait gdb connection to port
2755 Run the emulation in single step mode.
2758 Environment variables:
2762 Print system calls and arguments similar to the 'strace' program
2763 (NOTE: the actual 'strace' program will not work because the user
2764 space emulator hasn't implemented ptrace). At the moment this is
2765 incomplete. All system calls that don't have a specific argument
2766 format are printed with information for six arguments. Many
2767 flag-style arguments don't have decoders and will show up as numbers.
2770 @node Other binaries
2771 @subsection Other binaries
2773 @cindex user mode (Alpha)
2774 @command{qemu-alpha} TODO.
2776 @cindex user mode (ARM)
2777 @command{qemu-armeb} TODO.
2779 @cindex user mode (ARM)
2780 @command{qemu-arm} is also capable of running ARM "Angel" semihosted ELF
2781 binaries (as implemented by the arm-elf and arm-eabi Newlib/GDB
2782 configurations), and arm-uclinux bFLT format binaries.
2784 @cindex user mode (ColdFire)
2785 @cindex user mode (M68K)
2786 @command{qemu-m68k} is capable of running semihosted binaries using the BDM
2787 (m5xxx-ram-hosted.ld) or m68k-sim (sim.ld) syscall interfaces, and
2788 coldfire uClinux bFLT format binaries.
2790 The binary format is detected automatically.
2792 @cindex user mode (Cris)
2793 @command{qemu-cris} TODO.
2795 @cindex user mode (i386)
2796 @command{qemu-i386} TODO.
2797 @command{qemu-x86_64} TODO.
2799 @cindex user mode (Microblaze)
2800 @command{qemu-microblaze} TODO.
2802 @cindex user mode (MIPS)
2803 @command{qemu-mips} TODO.
2804 @command{qemu-mipsel} TODO.
2806 @cindex user mode (PowerPC)
2807 @command{qemu-ppc64abi32} TODO.
2808 @command{qemu-ppc64} TODO.
2809 @command{qemu-ppc} TODO.
2811 @cindex user mode (SH4)
2812 @command{qemu-sh4eb} TODO.
2813 @command{qemu-sh4} TODO.
2815 @cindex user mode (SPARC)
2816 @command{qemu-sparc} can execute Sparc32 binaries (Sparc32 CPU, 32 bit ABI).
2818 @command{qemu-sparc32plus} can execute Sparc32 and SPARC32PLUS binaries
2819 (Sparc64 CPU, 32 bit ABI).
2821 @command{qemu-sparc64} can execute some Sparc64 (Sparc64 CPU, 64 bit ABI) and
2822 SPARC32PLUS binaries (Sparc64 CPU, 32 bit ABI).
2824 @node BSD User space emulator
2825 @section BSD User space emulator
2830 * BSD Command line options::
2834 @subsection BSD Status
2838 target Sparc64 on Sparc64: Some trivial programs work.
2841 @node BSD Quick Start
2842 @subsection Quick Start
2844 In order to launch a BSD process, QEMU needs the process executable
2845 itself and all the target dynamic libraries used by it.
2849 @item On Sparc64, you can just try to launch any process by using the native
2853 qemu-sparc64 /bin/ls
2858 @node BSD Command line options
2859 @subsection Command line options
2862 usage: qemu-sparc64 [-h] [-d] [-L path] [-s size] [-bsd type] program [arguments...]
2869 Set the library root path (default=/)
2871 Set the stack size in bytes (default=524288)
2872 @item -ignore-environment
2873 Start with an empty environment. Without this option,
2874 the initial environment is a copy of the caller's environment.
2875 @item -E @var{var}=@var{value}
2876 Set environment @var{var} to @var{value}.
2878 Remove @var{var} from the environment.
2880 Set the type of the emulated BSD Operating system. Valid values are
2881 FreeBSD, NetBSD and OpenBSD (default).
2888 Activate logging of the specified items (use '-d help' for a list of log items)
2890 Act as if the host page size was 'pagesize' bytes
2892 Run the emulation in single step mode.
2896 @chapter Compilation from the sources
2901 * Cross compilation for Windows with Linux::
2909 @subsection Compilation
2911 First you must decompress the sources:
2914 tar zxvf qemu-x.y.z.tar.gz
2918 Then you configure QEMU and build it (usually no options are needed):
2924 Then type as root user:
2928 to install QEMU in @file{/usr/local}.
2934 @item Install the current versions of MSYS and MinGW from
2935 @url{http://www.mingw.org/}. You can find detailed installation
2936 instructions in the download section and the FAQ.
2939 the MinGW development library of SDL 1.2.x
2940 (@file{SDL-devel-1.2.x-@/mingw32.tar.gz}) from
2941 @url{http://www.libsdl.org}. Unpack it in a temporary place and
2942 edit the @file{sdl-config} script so that it gives the
2943 correct SDL directory when invoked.
2945 @item Install the MinGW version of zlib and make sure
2946 @file{zlib.h} and @file{libz.dll.a} are in
2947 MinGW's default header and linker search paths.
2949 @item Extract the current version of QEMU.
2951 @item Start the MSYS shell (file @file{msys.bat}).
2953 @item Change to the QEMU directory. Launch @file{./configure} and
2954 @file{make}. If you have problems using SDL, verify that
2955 @file{sdl-config} can be launched from the MSYS command line.
2957 @item You can install QEMU in @file{Program Files/QEMU} by typing
2958 @file{make install}. Don't forget to copy @file{SDL.dll} in
2959 @file{Program Files/QEMU}.
2963 @node Cross compilation for Windows with Linux
2964 @section Cross compilation for Windows with Linux
2968 Install the MinGW cross compilation tools available at
2969 @url{http://www.mingw.org/}.
2972 the MinGW development library of SDL 1.2.x
2973 (@file{SDL-devel-1.2.x-@/mingw32.tar.gz}) from
2974 @url{http://www.libsdl.org}. Unpack it in a temporary place and
2975 edit the @file{sdl-config} script so that it gives the
2976 correct SDL directory when invoked. Set up the @code{PATH} environment
2977 variable so that @file{sdl-config} can be launched by
2978 the QEMU configuration script.
2980 @item Install the MinGW version of zlib and make sure
2981 @file{zlib.h} and @file{libz.dll.a} are in
2982 MinGW's default header and linker search paths.
2985 Configure QEMU for Windows cross compilation:
2987 PATH=/usr/i686-pc-mingw32/sys-root/mingw/bin:$PATH ./configure --cross-prefix='i686-pc-mingw32-'
2989 The example assumes @file{sdl-config} is installed under @file{/usr/i686-pc-mingw32/sys-root/mingw/bin} and
2990 MinGW cross compilation tools have names like @file{i686-pc-mingw32-gcc} and @file{i686-pc-mingw32-strip}.
2991 We set the @code{PATH} environment variable to ensure the MinGW version of @file{sdl-config} is used and
2992 use --cross-prefix to specify the name of the cross compiler.
2993 You can also use --prefix to set the Win32 install path which defaults to @file{c:/Program Files/QEMU}.
2995 Under Fedora Linux, you can run:
2997 yum -y install mingw32-gcc mingw32-SDL mingw32-zlib
2999 to get a suitable cross compilation environment.
3001 @item You can install QEMU in the installation directory by typing
3002 @code{make install}. Don't forget to copy @file{SDL.dll} and @file{zlib1.dll} into the
3003 installation directory.
3007 @cindex wine, starting system emulation
3008 Wine can be used to launch the resulting qemu-system-i386.exe
3009 and all other qemu-system-@var{target}.exe compiled for Win32.
3011 wine qemu-system-i386
3017 The Mac OS X patches are not fully merged in QEMU, so you should look
3018 at the QEMU mailing list archive to have all the necessary
3019 information. (TODO: is this still true?)
3022 @section Make targets
3028 Make everything which is typically needed.
3037 Remove most files which were built during make.
3039 @item make distclean
3040 Remove everything which was built during make.
3046 Create documentation in dvi, html, info or pdf format.
3051 @item make defconfig
3052 (Re-)create some build configuration files.
3053 User made changes will be overwritten.
3064 QEMU is a trademark of Fabrice Bellard.
3066 QEMU is released under the GNU General Public License (TODO: add link).
3067 Parts of QEMU have specific licenses, see file LICENSE.
3069 TODO (refer to file LICENSE, include it, include the GPL?)
3083 @section Concept Index
3084 This is the main index. Should we combine all keywords in one index? TODO
3087 @node Function Index
3088 @section Function Index
3089 This index could be used for command line options and monitor functions.
3092 @node Keystroke Index
3093 @section Keystroke Index
3095 This is a list of all keystrokes which have a special function
3096 in system emulation.
3101 @section Program Index
3104 @node Data Type Index
3105 @section Data Type Index
3107 This index could be used for qdev device names and options.
3111 @node Variable Index
3112 @section Variable Index