1 \input texinfo @c -*- texinfo -*-
3 @setfilename qemu-doc.info
7 @documentencoding UTF-8
9 @settitle QEMU version @value{VERSION} User Documentation
16 * QEMU: (qemu-doc). The QEMU Emulator User Documentation.
23 @center @titlefont{QEMU version @value{VERSION}}
25 @center @titlefont{User Documentation}
36 * QEMU PC System emulator::
37 * QEMU System emulator for non PC targets::
39 * QEMU User space emulator::
40 * Implementation notes::
41 * Deprecated features::
53 * intro_features:: Features
59 QEMU is a FAST! processor emulator using dynamic translation to
60 achieve good emulation speed.
62 @cindex operating modes
63 QEMU has two operating modes:
66 @cindex system emulation
67 @item 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.
72 @cindex user mode emulation
73 @item User mode emulation. In this mode, QEMU can launch
74 processes compiled for one CPU on another CPU. It can be used to
75 launch the Wine Windows API emulator (@url{http://www.winehq.org}) or
76 to ease cross-compilation and cross-debugging.
80 QEMU has the following features:
83 @item QEMU can run without a host kernel driver and yet gives acceptable
84 performance. It uses dynamic translation to native code for reasonable speed,
85 with support for self-modifying code and precise exceptions.
87 @item It is portable to several operating systems (GNU/Linux, *BSD, Mac OS X,
88 Windows) and architectures.
90 @item It performs accurate software emulation of the FPU.
93 QEMU user mode emulation has the following features:
95 @item Generic Linux system call converter, including most ioctls.
97 @item clone() emulation using native CPU clone() to use Linux scheduler for threads.
99 @item Accurate signal handling by remapping host signals to target signals.
102 QEMU full system emulation has the following features:
105 QEMU uses a full software MMU for maximum portability.
108 QEMU can optionally use an in-kernel accelerator, like kvm. The accelerators
109 execute most of the guest code natively, while
110 continuing to emulate the rest of the machine.
113 Various hardware devices can be emulated and in some cases, host
114 devices (e.g. serial and parallel ports, USB, drives) can be used
115 transparently by the guest Operating System. Host device passthrough
116 can be used for talking to external physical peripherals (e.g. a
117 webcam, modem or tape drive).
120 Symmetric multiprocessing (SMP) support. Currently, an in-kernel
121 accelerator is required to use more than one host CPU for emulation.
126 @node QEMU PC System emulator
127 @chapter QEMU PC System emulator
128 @cindex system emulation (PC)
131 * pcsys_introduction:: Introduction
132 * pcsys_quickstart:: Quick Start
133 * sec_invocation:: Invocation
134 * pcsys_keys:: Keys in the graphical frontends
135 * mux_keys:: Keys in the character backend multiplexer
136 * pcsys_monitor:: QEMU Monitor
137 * disk_images:: Disk Images
138 * pcsys_network:: Network emulation
139 * pcsys_other_devs:: Other Devices
140 * direct_linux_boot:: Direct Linux Boot
141 * pcsys_usb:: USB emulation
142 * vnc_security:: VNC security
143 * gdb_usage:: GDB usage
144 * pcsys_os_specific:: Target OS specific information
147 @node pcsys_introduction
148 @section Introduction
150 @c man begin DESCRIPTION
152 The QEMU PC System emulator simulates the
153 following peripherals:
157 i440FX host PCI bridge and PIIX3 PCI to ISA bridge
159 Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
160 extensions (hardware level, including all non standard modes).
162 PS/2 mouse and keyboard
164 2 PCI IDE interfaces with hard disk and CD-ROM support
168 PCI and ISA network adapters
172 IPMI BMC, either and internal or external one
174 Creative SoundBlaster 16 sound card
176 ENSONIQ AudioPCI ES1370 sound card
178 Intel 82801AA AC97 Audio compatible sound card
180 Intel HD Audio Controller and HDA codec
182 Adlib (OPL2) - Yamaha YM3812 compatible chip
184 Gravis Ultrasound GF1 sound card
186 CS4231A compatible sound card
188 PCI UHCI, OHCI, EHCI or XHCI USB controller and a virtual USB-1.1 hub.
191 SMP is supported with up to 255 CPUs.
193 QEMU uses the PC BIOS from the Seabios project and the Plex86/Bochs LGPL
196 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
198 QEMU uses GUS emulation (GUSEMU32 @url{http://www.deinmeister.de/gusemu/})
199 by Tibor "TS" Schütz.
201 Note that, by default, GUS shares IRQ(7) with parallel ports and so
202 QEMU must be told to not have parallel ports to have working GUS.
205 qemu-system-i386 dos.img -soundhw gus -parallel none
210 qemu-system-i386 dos.img -device gus,irq=5
213 Or some other unclaimed IRQ.
215 CS4231A is the chip used in Windows Sound System and GUSMAX products
219 @node pcsys_quickstart
223 Download and uncompress the linux image (@file{linux.img}) and type:
226 qemu-system-i386 linux.img
229 Linux should boot and give you a prompt.
235 @c man begin SYNOPSIS
236 @command{qemu-system-i386} [@var{options}] [@var{disk_image}]
241 @var{disk_image} is a raw hard disk image for IDE hard disk 0. Some
242 targets do not need a disk image.
244 @include qemu-options.texi
249 @section Keys in the graphical frontends
253 During the graphical emulation, you can use special key combinations to change
254 modes. The default key mappings are shown below, but if you use @code{-alt-grab}
255 then the modifier is Ctrl-Alt-Shift (instead of Ctrl-Alt) and if you use
256 @code{-ctrl-grab} then the modifier is the right Ctrl key (instead of Ctrl-Alt):
273 Restore the screen's un-scaled dimensions
277 Switch to virtual console 'n'. Standard console mappings are:
280 Target system display
289 Toggle mouse and keyboard grab.
295 @kindex Ctrl-PageDown
296 In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
297 @key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
302 @section Keys in the character backend multiplexer
306 During emulation, if you are using a character backend multiplexer
307 (which is the default if you are using @option{-nographic}) then
308 several commands are available via an escape sequence. These
309 key sequences all start with an escape character, which is @key{Ctrl-a}
310 by default, but can be changed with @option{-echr}. The list below assumes
311 you're using the default.
322 Save disk data back to file (if -snapshot)
325 Toggle console timestamps
328 Send break (magic sysrq in Linux)
331 Rotate between the frontends connected to the multiplexer (usually
332 this switches between the monitor and the console)
334 @kindex Ctrl-a Ctrl-a
335 Send the escape character to the frontend
342 The HTML documentation of QEMU for more precise information and Linux
343 user mode emulator invocation.
353 @section QEMU Monitor
356 The QEMU monitor is used to give complex commands to the QEMU
357 emulator. You can use it to:
362 Remove or insert removable media images
363 (such as CD-ROM or floppies).
366 Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
369 @item Inspect the VM state without an external debugger.
375 The following commands are available:
377 @include qemu-monitor.texi
379 @include qemu-monitor-info.texi
381 @subsection Integer expressions
383 The monitor understands integers expressions for every integer
384 argument. You can use register names to get the value of specifics
385 CPU registers by prefixing them with @emph{$}.
390 QEMU supports many disk image formats, including growable disk images
391 (their size increase as non empty sectors are written), compressed and
392 encrypted disk images.
395 * disk_images_quickstart:: Quick start for disk image creation
396 * disk_images_snapshot_mode:: Snapshot mode
397 * vm_snapshots:: VM snapshots
398 * qemu_img_invocation:: qemu-img Invocation
399 * qemu_nbd_invocation:: qemu-nbd Invocation
400 * disk_images_formats:: Disk image file formats
401 * host_drives:: Using host drives
402 * disk_images_fat_images:: Virtual FAT disk images
403 * disk_images_nbd:: NBD access
404 * disk_images_sheepdog:: Sheepdog disk images
405 * disk_images_iscsi:: iSCSI LUNs
406 * disk_images_gluster:: GlusterFS disk images
407 * disk_images_ssh:: Secure Shell (ssh) disk images
410 @node disk_images_quickstart
411 @subsection Quick start for disk image creation
413 You can create a disk image with the command:
415 qemu-img create myimage.img mysize
417 where @var{myimage.img} is the disk image filename and @var{mysize} is its
418 size in kilobytes. You can add an @code{M} suffix to give the size in
419 megabytes and a @code{G} suffix for gigabytes.
421 See @ref{qemu_img_invocation} for more information.
423 @node disk_images_snapshot_mode
424 @subsection Snapshot mode
426 If you use the option @option{-snapshot}, all disk images are
427 considered as read only. When sectors in written, they are written in
428 a temporary file created in @file{/tmp}. You can however force the
429 write back to the raw disk images by using the @code{commit} monitor
430 command (or @key{C-a s} in the serial console).
433 @subsection VM snapshots
435 VM snapshots are snapshots of the complete virtual machine including
436 CPU state, RAM, device state and the content of all the writable
437 disks. In order to use VM snapshots, you must have at least one non
438 removable and writable block device using the @code{qcow2} disk image
439 format. Normally this device is the first virtual hard drive.
441 Use the monitor command @code{savevm} to create a new VM snapshot or
442 replace an existing one. A human readable name can be assigned to each
443 snapshot in addition to its numerical ID.
445 Use @code{loadvm} to restore a VM snapshot and @code{delvm} to remove
446 a VM snapshot. @code{info snapshots} lists the available snapshots
447 with their associated information:
450 (qemu) info snapshots
451 Snapshot devices: hda
452 Snapshot list (from hda):
453 ID TAG VM SIZE DATE VM CLOCK
454 1 start 41M 2006-08-06 12:38:02 00:00:14.954
455 2 40M 2006-08-06 12:43:29 00:00:18.633
456 3 msys 40M 2006-08-06 12:44:04 00:00:23.514
459 A VM snapshot is made of a VM state info (its size is shown in
460 @code{info snapshots}) and a snapshot of every writable disk image.
461 The VM state info is stored in the first @code{qcow2} non removable
462 and writable block device. The disk image snapshots are stored in
463 every disk image. The size of a snapshot in a disk image is difficult
464 to evaluate and is not shown by @code{info snapshots} because the
465 associated disk sectors are shared among all the snapshots to save
466 disk space (otherwise each snapshot would need a full copy of all the
469 When using the (unrelated) @code{-snapshot} option
470 (@ref{disk_images_snapshot_mode}), you can always make VM snapshots,
471 but they are deleted as soon as you exit QEMU.
473 VM snapshots currently have the following known limitations:
476 They cannot cope with removable devices if they are removed or
477 inserted after a snapshot is done.
479 A few device drivers still have incomplete snapshot support so their
480 state is not saved or restored properly (in particular USB).
483 @node qemu_img_invocation
484 @subsection @code{qemu-img} Invocation
486 @include qemu-img.texi
488 @node qemu_nbd_invocation
489 @subsection @code{qemu-nbd} Invocation
491 @include qemu-nbd.texi
493 @include docs/qemu-block-drivers.texi
496 @section Network emulation
498 QEMU can simulate several network cards (PCI or ISA cards on the PC
499 target) and can connect them to an arbitrary number of Virtual Local
500 Area Networks (VLANs). Host TAP devices can be connected to any QEMU
501 VLAN. VLAN can be connected between separate instances of QEMU to
502 simulate large networks. For simpler usage, a non privileged user mode
503 network stack can replace the TAP device to have a basic network
508 QEMU simulates several VLANs. A VLAN can be symbolised as a virtual
509 connection between several network devices. These devices can be for
510 example QEMU virtual Ethernet cards or virtual Host ethernet devices
513 @subsection Using TAP network interfaces
515 This is the standard way to connect QEMU to a real network. QEMU adds
516 a virtual network device on your host (called @code{tapN}), and you
517 can then configure it as if it was a real ethernet card.
519 @subsubsection Linux host
521 As an example, you can download the @file{linux-test-xxx.tar.gz}
522 archive and copy the script @file{qemu-ifup} in @file{/etc} and
523 configure properly @code{sudo} so that the command @code{ifconfig}
524 contained in @file{qemu-ifup} can be executed as root. You must verify
525 that your host kernel supports the TAP network interfaces: the
526 device @file{/dev/net/tun} must be present.
528 See @ref{sec_invocation} to have examples of command lines using the
529 TAP network interfaces.
531 @subsubsection Windows host
533 There is a virtual ethernet driver for Windows 2000/XP systems, called
534 TAP-Win32. But it is not included in standard QEMU for Windows,
535 so you will need to get it separately. It is part of OpenVPN package,
536 so download OpenVPN from : @url{http://openvpn.net/}.
538 @subsection Using the user mode network stack
540 By using the option @option{-net user} (default configuration if no
541 @option{-net} option is specified), QEMU uses a completely user mode
542 network stack (you don't need root privilege to use the virtual
543 network). The virtual network configuration is the following:
547 QEMU VLAN <------> Firewall/DHCP server <-----> Internet
550 ----> DNS server (10.0.2.3)
552 ----> SMB server (10.0.2.4)
555 The QEMU VM behaves as if it was behind a firewall which blocks all
556 incoming connections. You can use a DHCP client to automatically
557 configure the network in the QEMU VM. The DHCP server assign addresses
558 to the hosts starting from 10.0.2.15.
560 In order to check that the user mode network is working, you can ping
561 the address 10.0.2.2 and verify that you got an address in the range
562 10.0.2.x from the QEMU virtual DHCP server.
564 Note that ICMP traffic in general does not work with user mode networking.
565 @code{ping}, aka. ICMP echo, to the local router (10.0.2.2) shall work,
566 however. If you're using QEMU on Linux >= 3.0, it can use unprivileged ICMP
567 ping sockets to allow @code{ping} to the Internet. The host admin has to set
568 the ping_group_range in order to grant access to those sockets. To allow ping
569 for GID 100 (usually users group):
572 echo 100 100 > /proc/sys/net/ipv4/ping_group_range
575 When using the built-in TFTP server, the router is also the TFTP
578 When using the @option{'-netdev user,hostfwd=...'} option, TCP or UDP
579 connections can be redirected from the host to the guest. It allows for
580 example to redirect X11, telnet or SSH connections.
582 @subsection Connecting VLANs between QEMU instances
584 Using the @option{-net socket} option, it is possible to make VLANs
585 that span several QEMU instances. See @ref{sec_invocation} to have a
588 @node pcsys_other_devs
589 @section Other Devices
591 @subsection Inter-VM Shared Memory device
593 On Linux hosts, a shared memory device is available. The basic syntax
597 qemu-system-x86_64 -device ivshmem-plain,memdev=@var{hostmem}
600 where @var{hostmem} names a host memory backend. For a POSIX shared
601 memory backend, use something like
604 -object memory-backend-file,size=1M,share,mem-path=/dev/shm/ivshmem,id=@var{hostmem}
607 If desired, interrupts can be sent between guest VMs accessing the same shared
608 memory region. Interrupt support requires using a shared memory server and
609 using a chardev socket to connect to it. The code for the shared memory server
610 is qemu.git/contrib/ivshmem-server. An example syntax when using the shared
614 # First start the ivshmem server once and for all
615 ivshmem-server -p @var{pidfile} -S @var{path} -m @var{shm-name} -l @var{shm-size} -n @var{vectors}
617 # Then start your qemu instances with matching arguments
618 qemu-system-x86_64 -device ivshmem-doorbell,vectors=@var{vectors},chardev=@var{id}
619 -chardev socket,path=@var{path},id=@var{id}
622 When using the server, the guest will be assigned a VM ID (>=0) that allows guests
623 using the same server to communicate via interrupts. Guests can read their
624 VM ID from a device register (see ivshmem-spec.txt).
626 @subsubsection Migration with ivshmem
628 With device property @option{master=on}, the guest will copy the shared
629 memory on migration to the destination host. With @option{master=off},
630 the guest will not be able to migrate with the device attached. In the
631 latter case, the device should be detached and then reattached after
632 migration using the PCI hotplug support.
634 At most one of the devices sharing the same memory can be master. The
635 master must complete migration before you plug back the other devices.
637 @subsubsection ivshmem and hugepages
639 Instead of specifying the <shm size> using POSIX shm, you may specify
640 a memory backend that has hugepage support:
643 qemu-system-x86_64 -object memory-backend-file,size=1G,mem-path=/dev/hugepages/my-shmem-file,share,id=mb1
644 -device ivshmem-plain,memdev=mb1
647 ivshmem-server also supports hugepages mount points with the
648 @option{-m} memory path argument.
650 @node direct_linux_boot
651 @section Direct Linux Boot
653 This section explains how to launch a Linux kernel inside QEMU without
654 having to make a full bootable image. It is very useful for fast Linux
659 qemu-system-i386 -kernel arch/i386/boot/bzImage -hda root-2.4.20.img -append "root=/dev/hda"
662 Use @option{-kernel} to provide the Linux kernel image and
663 @option{-append} to give the kernel command line arguments. The
664 @option{-initrd} option can be used to provide an INITRD image.
666 When using the direct Linux boot, a disk image for the first hard disk
667 @file{hda} is required because its boot sector is used to launch the
670 If you do not need graphical output, you can disable it and redirect
671 the virtual serial port and the QEMU monitor to the console with the
672 @option{-nographic} option. The typical command line is:
674 qemu-system-i386 -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
675 -append "root=/dev/hda console=ttyS0" -nographic
678 Use @key{Ctrl-a c} to switch between the serial console and the
679 monitor (@pxref{pcsys_keys}).
682 @section USB emulation
684 QEMU can emulate a PCI UHCI, OHCI, EHCI or XHCI USB controller. You can
685 plug virtual USB devices or real host USB devices (only works with certain
686 host operating systems). QEMU will automatically create and connect virtual
687 USB hubs as necessary to connect multiple USB devices.
694 @subsection Connecting USB devices
696 USB devices can be connected with the @option{-device usb-...} command line
697 option or the @code{device_add} monitor command. Available devices are:
701 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
703 Pointer device that uses absolute coordinates (like a touchscreen).
704 This means QEMU is able to report the mouse position without having
705 to grab the mouse. Also overrides the PS/2 mouse emulation when activated.
706 @item usb-storage,drive=@var{drive_id}
707 Mass storage device backed by @var{drive_id} (@pxref{disk_images})
709 USB attached SCSI device, see
710 @url{http://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/usb-storage.txt,usb-storage.txt}
713 Bulk-only transport storage device, see
714 @url{http://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/usb-storage.txt,usb-storage.txt}
715 for details here, too
716 @item usb-mtp,x-root=@var{dir}
717 Media transfer protocol device, using @var{dir} as root of the file tree
718 that is presented to the guest.
719 @item usb-host,hostbus=@var{bus},hostaddr=@var{addr}
720 Pass through the host device identified by @var{bus} and @var{addr}
721 @item usb-host,vendorid=@var{vendor},productid=@var{product}
722 Pass through the host device identified by @var{vendor} and @var{product} ID
723 @item usb-wacom-tablet
724 Virtual Wacom PenPartner tablet. This device is similar to the @code{tablet}
725 above but it can be used with the tslib library because in addition to touch
726 coordinates it reports touch pressure.
728 Standard USB keyboard. Will override the PS/2 keyboard (if present).
729 @item usb-serial,chardev=@var{id}
730 Serial converter. This emulates an FTDI FT232BM chip connected to host character
732 @item usb-braille,chardev=@var{id}
733 Braille device. This will use BrlAPI to display the braille output on a real
734 or fake device referenced by @var{id}.
735 @item usb-net[,netdev=@var{id}]
736 Network adapter that supports CDC ethernet and RNDIS protocols. @var{id}
737 specifies a netdev defined with @code{-netdev @dots{},id=@var{id}}.
738 For instance, user-mode networking can be used with
740 qemu-system-i386 [...] -netdev user,id=net0 -device usb-net,netdev=net0
743 Smartcard reader device
747 Bluetooth dongle for the transport layer of HCI. It is connected to HCI
748 scatternet 0 by default (corresponds to @code{-bt hci,vlan=0}).
749 Note that the syntax for the @code{-device usb-bt-dongle} option is not as
750 useful yet as it was with the legacy @code{-usbdevice} option. So to
751 configure an USB bluetooth device, you might need to use
752 "@code{-usbdevice bt}[:@var{hci-type}]" instead. This configures a
753 bluetooth dongle whose type is specified in the same format as with
754 the @option{-bt hci} option, @pxref{bt-hcis,,allowed HCI types}. If
755 no type is given, the HCI logic corresponds to @code{-bt hci,vlan=0}.
756 This USB device implements the USB Transport Layer of HCI. Example
759 @command{qemu-system-i386} [...@var{OPTIONS}...] @option{-usbdevice} bt:hci,vlan=3 @option{-bt} device:keyboard,vlan=3
763 @node host_usb_devices
764 @subsection Using host USB devices on a Linux host
766 WARNING: this is an experimental feature. QEMU will slow down when
767 using it. USB devices requiring real time streaming (i.e. USB Video
768 Cameras) are not supported yet.
771 @item If you use an early Linux 2.4 kernel, verify that no Linux driver
772 is actually using the USB device. A simple way to do that is simply to
773 disable the corresponding kernel module by renaming it from @file{mydriver.o}
774 to @file{mydriver.o.disabled}.
776 @item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
782 @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:
784 chown -R myuid /proc/bus/usb
787 @item Launch QEMU and do in the monitor:
790 Device 1.2, speed 480 Mb/s
791 Class 00: USB device 1234:5678, USB DISK
793 You should see the list of the devices you can use (Never try to use
794 hubs, it won't work).
796 @item Add the device in QEMU by using:
798 device_add usb-host,vendorid=0x1234,productid=0x5678
801 Normally the guest OS should report that a new USB device is plugged.
802 You can use the option @option{-device usb-host,...} to do the same.
804 @item Now you can try to use the host USB device in QEMU.
808 When relaunching QEMU, you may have to unplug and plug again the USB
809 device to make it work again (this is a bug).
812 @section VNC security
814 The VNC server capability provides access to the graphical console
815 of the guest VM across the network. This has a number of security
816 considerations depending on the deployment scenarios.
821 * vnc_sec_certificate::
822 * vnc_sec_certificate_verify::
823 * vnc_sec_certificate_pw::
825 * vnc_sec_certificate_sasl::
826 * vnc_generate_cert::
830 @subsection Without passwords
832 The simplest VNC server setup does not include any form of authentication.
833 For this setup it is recommended to restrict it to listen on a UNIX domain
834 socket only. For example
837 qemu-system-i386 [...OPTIONS...] -vnc unix:/home/joebloggs/.qemu-myvm-vnc
840 This ensures that only users on local box with read/write access to that
841 path can access the VNC server. To securely access the VNC server from a
842 remote machine, a combination of netcat+ssh can be used to provide a secure
845 @node vnc_sec_password
846 @subsection With passwords
848 The VNC protocol has limited support for password based authentication. Since
849 the protocol limits passwords to 8 characters it should not be considered
850 to provide high security. The password can be fairly easily brute-forced by
851 a client making repeat connections. For this reason, a VNC server using password
852 authentication should be restricted to only listen on the loopback interface
853 or UNIX domain sockets. Password authentication is not supported when operating
854 in FIPS 140-2 compliance mode as it requires the use of the DES cipher. Password
855 authentication is requested with the @code{password} option, and then once QEMU
856 is running the password is set with the monitor. Until the monitor is used to
857 set the password all clients will be rejected.
860 qemu-system-i386 [...OPTIONS...] -vnc :1,password -monitor stdio
861 (qemu) change vnc password
866 @node vnc_sec_certificate
867 @subsection With x509 certificates
869 The QEMU VNC server also implements the VeNCrypt extension allowing use of
870 TLS for encryption of the session, and x509 certificates for authentication.
871 The use of x509 certificates is strongly recommended, because TLS on its
872 own is susceptible to man-in-the-middle attacks. Basic x509 certificate
873 support provides a secure session, but no authentication. This allows any
874 client to connect, and provides an encrypted session.
877 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509=/etc/pki/qemu -monitor stdio
880 In the above example @code{/etc/pki/qemu} should contain at least three files,
881 @code{ca-cert.pem}, @code{server-cert.pem} and @code{server-key.pem}. Unprivileged
882 users will want to use a private directory, for example @code{$HOME/.pki/qemu}.
883 NB the @code{server-key.pem} file should be protected with file mode 0600 to
884 only be readable by the user owning it.
886 @node vnc_sec_certificate_verify
887 @subsection With x509 certificates and client verification
889 Certificates can also provide a means to authenticate the client connecting.
890 The server will request that the client provide a certificate, which it will
891 then validate against the CA certificate. This is a good choice if deploying
892 in an environment with a private internal certificate authority.
895 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509verify=/etc/pki/qemu -monitor stdio
899 @node vnc_sec_certificate_pw
900 @subsection With x509 certificates, client verification and passwords
902 Finally, the previous method can be combined with VNC password authentication
903 to provide two layers of authentication for clients.
906 qemu-system-i386 [...OPTIONS...] -vnc :1,password,tls,x509verify=/etc/pki/qemu -monitor stdio
907 (qemu) change vnc password
914 @subsection With SASL authentication
916 The SASL authentication method is a VNC extension, that provides an
917 easily extendable, pluggable authentication method. This allows for
918 integration with a wide range of authentication mechanisms, such as
919 PAM, GSSAPI/Kerberos, LDAP, SQL databases, one-time keys and more.
920 The strength of the authentication depends on the exact mechanism
921 configured. If the chosen mechanism also provides a SSF layer, then
922 it will encrypt the datastream as well.
924 Refer to the later docs on how to choose the exact SASL mechanism
925 used for authentication, but assuming use of one supporting SSF,
926 then QEMU can be launched with:
929 qemu-system-i386 [...OPTIONS...] -vnc :1,sasl -monitor stdio
932 @node vnc_sec_certificate_sasl
933 @subsection With x509 certificates and SASL authentication
935 If the desired SASL authentication mechanism does not supported
936 SSF layers, then it is strongly advised to run it in combination
937 with TLS and x509 certificates. This provides securely encrypted
938 data stream, avoiding risk of compromising of the security
939 credentials. This can be enabled, by combining the 'sasl' option
940 with the aforementioned TLS + x509 options:
943 qemu-system-i386 [...OPTIONS...] -vnc :1,tls,x509,sasl -monitor stdio
947 @node vnc_generate_cert
948 @subsection Generating certificates for VNC
950 The GNU TLS packages provides a command called @code{certtool} which can
951 be used to generate certificates and keys in PEM format. At a minimum it
952 is necessary to setup a certificate authority, and issue certificates to
953 each server. If using certificates for authentication, then each client
954 will also need to be issued a certificate. The recommendation is for the
955 server to keep its certificates in either @code{/etc/pki/qemu} or for
956 unprivileged users in @code{$HOME/.pki/qemu}.
960 * vnc_generate_server::
961 * vnc_generate_client::
963 @node vnc_generate_ca
964 @subsubsection Setup the Certificate Authority
966 This step only needs to be performed once per organization / organizational
967 unit. First the CA needs a private key. This key must be kept VERY secret
968 and secure. If this key is compromised the entire trust chain of the certificates
969 issued with it is lost.
972 # certtool --generate-privkey > ca-key.pem
975 A CA needs to have a public certificate. For simplicity it can be a self-signed
976 certificate, or one issue by a commercial certificate issuing authority. To
977 generate a self-signed certificate requires one core piece of information, the
978 name of the organization.
981 # cat > ca.info <<EOF
982 cn = Name of your organization
986 # certtool --generate-self-signed \
987 --load-privkey ca-key.pem
989 --outfile ca-cert.pem
992 The @code{ca-cert.pem} file should be copied to all servers and clients wishing to utilize
993 TLS support in the VNC server. The @code{ca-key.pem} must not be disclosed/copied at all.
995 @node vnc_generate_server
996 @subsubsection Issuing server certificates
998 Each server (or host) needs to be issued with a key and certificate. When connecting
999 the certificate is sent to the client which validates it against the CA certificate.
1000 The core piece of information for a server certificate is the hostname. This should
1001 be the fully qualified hostname that the client will connect with, since the client
1002 will typically also verify the hostname in the certificate. On the host holding the
1003 secure CA private key:
1006 # cat > server.info <<EOF
1007 organization = Name of your organization
1008 cn = server.foo.example.com
1013 # certtool --generate-privkey > server-key.pem
1014 # certtool --generate-certificate \
1015 --load-ca-certificate ca-cert.pem \
1016 --load-ca-privkey ca-key.pem \
1017 --load-privkey server-key.pem \
1018 --template server.info \
1019 --outfile server-cert.pem
1022 The @code{server-key.pem} and @code{server-cert.pem} files should now be securely copied
1023 to the server for which they were generated. The @code{server-key.pem} is security
1024 sensitive and should be kept protected with file mode 0600 to prevent disclosure.
1026 @node vnc_generate_client
1027 @subsubsection Issuing client certificates
1029 If the QEMU VNC server is to use the @code{x509verify} option to validate client
1030 certificates as its authentication mechanism, each client also needs to be issued
1031 a certificate. The client certificate contains enough metadata to uniquely identify
1032 the client, typically organization, state, city, building, etc. On the host holding
1033 the secure CA private key:
1036 # cat > client.info <<EOF
1040 organization = Name of your organization
1041 cn = client.foo.example.com
1046 # certtool --generate-privkey > client-key.pem
1047 # certtool --generate-certificate \
1048 --load-ca-certificate ca-cert.pem \
1049 --load-ca-privkey ca-key.pem \
1050 --load-privkey client-key.pem \
1051 --template client.info \
1052 --outfile client-cert.pem
1055 The @code{client-key.pem} and @code{client-cert.pem} files should now be securely
1056 copied to the client for which they were generated.
1059 @node vnc_setup_sasl
1061 @subsection Configuring SASL mechanisms
1063 The following documentation assumes use of the Cyrus SASL implementation on a
1064 Linux host, but the principals should apply to any other SASL impl. When SASL
1065 is enabled, the mechanism configuration will be loaded from system default
1066 SASL service config /etc/sasl2/qemu.conf. If running QEMU as an
1067 unprivileged user, an environment variable SASL_CONF_PATH can be used
1068 to make it search alternate locations for the service config.
1070 If the TLS option is enabled for VNC, then it will provide session encryption,
1071 otherwise the SASL mechanism will have to provide encryption. In the latter
1072 case the list of possible plugins that can be used is drastically reduced. In
1073 fact only the GSSAPI SASL mechanism provides an acceptable level of security
1074 by modern standards. Previous versions of QEMU referred to the DIGEST-MD5
1075 mechanism, however, it has multiple serious flaws described in detail in
1076 RFC 6331 and thus should never be used any more. The SCRAM-SHA-1 mechanism
1077 provides a simple username/password auth facility similar to DIGEST-MD5, but
1078 does not support session encryption, so can only be used in combination with
1081 When not using TLS the recommended configuration is
1085 keytab: /etc/qemu/krb5.tab
1088 This says to use the 'GSSAPI' mechanism with the Kerberos v5 protocol, with
1089 the server principal stored in /etc/qemu/krb5.tab. For this to work the
1090 administrator of your KDC must generate a Kerberos principal for the server,
1091 with a name of 'qemu/somehost.example.com@@EXAMPLE.COM' replacing
1092 'somehost.example.com' with the fully qualified host name of the machine
1093 running QEMU, and 'EXAMPLE.COM' with the Kerberos Realm.
1095 When using TLS, if username+password authentication is desired, then a
1096 reasonable configuration is
1099 mech_list: scram-sha-1
1100 sasldb_path: /etc/qemu/passwd.db
1103 The saslpasswd2 program can be used to populate the passwd.db file with
1106 Other SASL configurations will be left as an exercise for the reader. Note that
1107 all mechanisms except GSSAPI, should be combined with use of TLS to ensure a
1108 secure data channel.
1113 QEMU has a primitive support to work with gdb, so that you can do
1114 'Ctrl-C' while the virtual machine is running and inspect its state.
1116 In order to use gdb, launch QEMU with the '-s' option. It will wait for a
1119 qemu-system-i386 -s -kernel arch/i386/boot/bzImage -hda root-2.4.20.img \
1120 -append "root=/dev/hda"
1121 Connected to host network interface: tun0
1122 Waiting gdb connection on port 1234
1125 Then launch gdb on the 'vmlinux' executable:
1130 In gdb, connect to QEMU:
1132 (gdb) target remote localhost:1234
1135 Then you can use gdb normally. For example, type 'c' to launch the kernel:
1140 Here are some useful tips in order to use gdb on system code:
1144 Use @code{info reg} to display all the CPU registers.
1146 Use @code{x/10i $eip} to display the code at the PC position.
1148 Use @code{set architecture i8086} to dump 16 bit code. Then use
1149 @code{x/10i $cs*16+$eip} to dump the code at the PC position.
1152 Advanced debugging options:
1154 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 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:
1156 @item maintenance packet qqemu.sstepbits
1158 This will display the MASK bits used to control the single stepping IE:
1160 (gdb) maintenance packet qqemu.sstepbits
1161 sending: "qqemu.sstepbits"
1162 received: "ENABLE=1,NOIRQ=2,NOTIMER=4"
1164 @item maintenance packet qqemu.sstep
1166 This will display the current value of the mask used when single stepping IE:
1168 (gdb) maintenance packet qqemu.sstep
1169 sending: "qqemu.sstep"
1172 @item maintenance packet Qqemu.sstep=HEX_VALUE
1174 This will change the single step mask, so if wanted to enable IRQs on the single step, but not timers, you would use:
1176 (gdb) maintenance packet Qqemu.sstep=0x5
1177 sending: "qemu.sstep=0x5"
1182 @node pcsys_os_specific
1183 @section Target OS specific information
1187 To have access to SVGA graphic modes under X11, use the @code{vesa} or
1188 the @code{cirrus} X11 driver. For optimal performances, use 16 bit
1189 color depth in the guest and the host OS.
1191 When using a 2.6 guest Linux kernel, you should add the option
1192 @code{clock=pit} on the kernel command line because the 2.6 Linux
1193 kernels make very strict real time clock checks by default that QEMU
1194 cannot simulate exactly.
1196 When using a 2.6 guest Linux kernel, verify that the 4G/4G patch is
1197 not activated because QEMU is slower with this patch. The QEMU
1198 Accelerator Module is also much slower in this case. Earlier Fedora
1199 Core 3 Linux kernel (< 2.6.9-1.724_FC3) were known to incorporate this
1200 patch by default. Newer kernels don't have it.
1204 If you have a slow host, using Windows 95 is better as it gives the
1205 best speed. Windows 2000 is also a good choice.
1207 @subsubsection SVGA graphic modes support
1209 QEMU emulates a Cirrus Logic GD5446 Video
1210 card. All Windows versions starting from Windows 95 should recognize
1211 and use this graphic card. For optimal performances, use 16 bit color
1212 depth in the guest and the host OS.
1214 If you are using Windows XP as guest OS and if you want to use high
1215 resolution modes which the Cirrus Logic BIOS does not support (i.e. >=
1216 1280x1024x16), then you should use the VESA VBE virtual graphic card
1217 (option @option{-std-vga}).
1219 @subsubsection CPU usage reduction
1221 Windows 9x does not correctly use the CPU HLT
1222 instruction. The result is that it takes host CPU cycles even when
1223 idle. You can install the utility from
1224 @url{http://web.archive.org/web/20060212132151/http://www.user.cityline.ru/~maxamn/amnhltm.zip}
1225 to solve this problem. Note that no such tool is needed for NT, 2000 or XP.
1227 @subsubsection Windows 2000 disk full problem
1229 Windows 2000 has a bug which gives a disk full problem during its
1230 installation. When installing it, use the @option{-win2k-hack} QEMU
1231 option to enable a specific workaround. After Windows 2000 is
1232 installed, you no longer need this option (this option slows down the
1235 @subsubsection Windows 2000 shutdown
1237 Windows 2000 cannot automatically shutdown in QEMU although Windows 98
1238 can. It comes from the fact that Windows 2000 does not automatically
1239 use the APM driver provided by the BIOS.
1241 In order to correct that, do the following (thanks to Struan
1242 Bartlett): go to the Control Panel => Add/Remove Hardware & Next =>
1243 Add/Troubleshoot a device => Add a new device & Next => No, select the
1244 hardware from a list & Next => NT Apm/Legacy Support & Next => Next
1245 (again) a few times. Now the driver is installed and Windows 2000 now
1246 correctly instructs QEMU to shutdown at the appropriate moment.
1248 @subsubsection Share a directory between Unix and Windows
1250 See @ref{sec_invocation} about the help of the option
1251 @option{'-netdev user,smb=...'}.
1253 @subsubsection Windows XP security problem
1255 Some releases of Windows XP install correctly but give a security
1258 A problem is preventing Windows from accurately checking the
1259 license for this computer. Error code: 0x800703e6.
1262 The workaround is to install a service pack for XP after a boot in safe
1263 mode. Then reboot, and the problem should go away. Since there is no
1264 network while in safe mode, its recommended to download the full
1265 installation of SP1 or SP2 and transfer that via an ISO or using the
1266 vvfat block device ("-hdb fat:directory_which_holds_the_SP").
1268 @subsection MS-DOS and FreeDOS
1270 @subsubsection CPU usage reduction
1272 DOS does not correctly use the CPU HLT instruction. The result is that
1273 it takes host CPU cycles even when idle. You can install the utility from
1274 @url{http://web.archive.org/web/20051222085335/http://www.vmware.com/software/dosidle210.zip}
1275 to solve this problem.
1277 @node QEMU System emulator for non PC targets
1278 @chapter QEMU System emulator for non PC targets
1280 QEMU is a generic emulator and it emulates many non PC
1281 machines. Most of the options are similar to the PC emulator. The
1282 differences are mentioned in the following sections.
1285 * PowerPC System emulator::
1286 * Sparc32 System emulator::
1287 * Sparc64 System emulator::
1288 * MIPS System emulator::
1289 * ARM System emulator::
1290 * ColdFire System emulator::
1291 * Cris System emulator::
1292 * Microblaze System emulator::
1293 * SH4 System emulator::
1294 * Xtensa System emulator::
1297 @node PowerPC System emulator
1298 @section PowerPC System emulator
1299 @cindex system emulation (PowerPC)
1301 Use the executable @file{qemu-system-ppc} to simulate a complete PREP
1302 or PowerMac PowerPC system.
1304 QEMU emulates the following PowerMac peripherals:
1308 UniNorth or Grackle PCI Bridge
1310 PCI VGA compatible card with VESA Bochs Extensions
1312 2 PMAC IDE interfaces with hard disk and CD-ROM support
1318 VIA-CUDA with ADB keyboard and mouse.
1321 QEMU emulates the following PREP peripherals:
1327 PCI VGA compatible card with VESA Bochs Extensions
1329 2 IDE interfaces with hard disk and CD-ROM support
1333 NE2000 network adapters
1337 PREP Non Volatile RAM
1339 PC compatible keyboard and mouse.
1342 QEMU uses the Open Hack'Ware Open Firmware Compatible BIOS.
1344 Since version 0.9.1, QEMU uses OpenBIOS @url{http://www.openbios.org/}
1345 for the g3beige and mac99 PowerMac machines. OpenBIOS is a free (GPL
1346 v2) portable firmware implementation. The goal is to implement a 100%
1347 IEEE 1275-1994 (referred to as Open Firmware) compliant firmware.
1349 @c man begin OPTIONS
1351 The following options are specific to the PowerPC emulation:
1355 @item -g @var{W}x@var{H}[x@var{DEPTH}]
1357 Set the initial VGA graphic mode. The default is 800x600x32.
1359 @item -prom-env @var{string}
1361 Set OpenBIOS variables in NVRAM, for example:
1364 qemu-system-ppc -prom-env 'auto-boot?=false' \
1365 -prom-env 'boot-device=hd:2,\yaboot' \
1366 -prom-env 'boot-args=conf=hd:2,\yaboot.conf'
1369 These variables are not used by Open Hack'Ware.
1375 @node Sparc32 System emulator
1376 @section Sparc32 System emulator
1377 @cindex system emulation (Sparc32)
1379 Use the executable @file{qemu-system-sparc} to simulate the following
1380 Sun4m architecture machines:
1395 SPARCstation Voyager
1402 The emulation is somewhat complete. SMP up to 16 CPUs is supported,
1403 but Linux limits the number of usable CPUs to 4.
1405 QEMU emulates the following sun4m peripherals:
1411 TCX or cgthree Frame buffer
1413 Lance (Am7990) Ethernet
1415 Non Volatile RAM M48T02/M48T08
1417 Slave I/O: timers, interrupt controllers, Zilog serial ports, keyboard
1418 and power/reset logic
1420 ESP SCSI controller with hard disk and CD-ROM support
1422 Floppy drive (not on SS-600MP)
1424 CS4231 sound device (only on SS-5, not working yet)
1427 The number of peripherals is fixed in the architecture. Maximum
1428 memory size depends on the machine type, for SS-5 it is 256MB and for
1431 Since version 0.8.2, QEMU uses OpenBIOS
1432 @url{http://www.openbios.org/}. OpenBIOS is a free (GPL v2) portable
1433 firmware implementation. The goal is to implement a 100% IEEE
1434 1275-1994 (referred to as Open Firmware) compliant firmware.
1436 A sample Linux 2.6 series kernel and ram disk image are available on
1437 the QEMU web site. There are still issues with NetBSD and OpenBSD, but
1438 most kernel versions work. Please note that currently older Solaris kernels
1439 don't work probably due to interface issues between OpenBIOS and
1442 @c man begin OPTIONS
1444 The following options are specific to the Sparc32 emulation:
1448 @item -g @var{W}x@var{H}x[x@var{DEPTH}]
1450 Set the initial graphics mode. For TCX, the default is 1024x768x8 with the
1451 option of 1024x768x24. For cgthree, the default is 1024x768x8 with the option
1452 of 1152x900x8 for people who wish to use OBP.
1454 @item -prom-env @var{string}
1456 Set OpenBIOS variables in NVRAM, for example:
1459 qemu-system-sparc -prom-env 'auto-boot?=false' \
1460 -prom-env 'boot-device=sd(0,2,0):d' -prom-env 'boot-args=linux single'
1463 @item -M [SS-4|SS-5|SS-10|SS-20|SS-600MP|LX|Voyager|SPARCClassic] [|SPARCbook]
1465 Set the emulated machine type. Default is SS-5.
1471 @node Sparc64 System emulator
1472 @section Sparc64 System emulator
1473 @cindex system emulation (Sparc64)
1475 Use the executable @file{qemu-system-sparc64} to simulate a Sun4u
1476 (UltraSPARC PC-like machine), Sun4v (T1 PC-like machine), or generic
1477 Niagara (T1) machine. The Sun4u emulator is mostly complete, being
1478 able to run Linux, NetBSD and OpenBSD in headless (-nographic) mode. The
1479 Sun4v emulator is still a work in progress.
1481 The Niagara T1 emulator makes use of firmware and OS binaries supplied in the S10image/ directory
1482 of the OpenSPARC T1 project @url{http://download.oracle.com/technetwork/systems/opensparc/OpenSPARCT1_Arch.1.5.tar.bz2}
1483 and is able to boot the disk.s10hw2 Solaris image.
1485 qemu-system-sparc64 -M niagara -L /path-to/S10image/ \
1487 -drive if=pflash,readonly=on,file=/S10image/disk.s10hw2
1491 QEMU emulates the following peripherals:
1495 UltraSparc IIi APB PCI Bridge
1497 PCI VGA compatible card with VESA Bochs Extensions
1499 PS/2 mouse and keyboard
1501 Non Volatile RAM M48T59
1503 PC-compatible serial ports
1505 2 PCI IDE interfaces with hard disk and CD-ROM support
1510 @c man begin OPTIONS
1512 The following options are specific to the Sparc64 emulation:
1516 @item -prom-env @var{string}
1518 Set OpenBIOS variables in NVRAM, for example:
1521 qemu-system-sparc64 -prom-env 'auto-boot?=false'
1524 @item -M [sun4u|sun4v|niagara]
1526 Set the emulated machine type. The default is sun4u.
1532 @node MIPS System emulator
1533 @section MIPS System emulator
1534 @cindex system emulation (MIPS)
1536 Four executables cover simulation of 32 and 64-bit MIPS systems in
1537 both endian options, @file{qemu-system-mips}, @file{qemu-system-mipsel}
1538 @file{qemu-system-mips64} and @file{qemu-system-mips64el}.
1539 Five different machine types are emulated:
1543 A generic ISA PC-like machine "mips"
1545 The MIPS Malta prototype board "malta"
1547 An ACER Pica "pica61". This machine needs the 64-bit emulator.
1549 MIPS emulator pseudo board "mipssim"
1551 A MIPS Magnum R4000 machine "magnum". This machine needs the 64-bit emulator.
1554 The generic emulation is supported by Debian 'Etch' and is able to
1555 install Debian into a virtual disk image. The following devices are
1560 A range of MIPS CPUs, default is the 24Kf
1562 PC style serial port
1569 The Malta emulation supports the following devices:
1573 Core board with MIPS 24Kf CPU and Galileo system controller
1575 PIIX4 PCI/USB/SMbus controller
1577 The Multi-I/O chip's serial device
1579 PCI network cards (PCnet32 and others)
1581 Malta FPGA serial device
1583 Cirrus (default) or any other PCI VGA graphics card
1586 The ACER Pica emulation supports:
1592 PC-style IRQ and DMA controllers
1599 The mipssim pseudo board emulation provides an environment similar
1600 to what the proprietary MIPS emulator uses for running Linux.
1605 A range of MIPS CPUs, default is the 24Kf
1607 PC style serial port
1609 MIPSnet network emulation
1612 The MIPS Magnum R4000 emulation supports:
1618 PC-style IRQ controller
1628 @node ARM System emulator
1629 @section ARM System emulator
1630 @cindex system emulation (ARM)
1632 Use the executable @file{qemu-system-arm} to simulate a ARM
1633 machine. The ARM Integrator/CP board is emulated with the following
1638 ARM926E, ARM1026E, ARM946E, ARM1136 or Cortex-A8 CPU
1642 SMC 91c111 Ethernet adapter
1644 PL110 LCD controller
1646 PL050 KMI with PS/2 keyboard and mouse.
1648 PL181 MultiMedia Card Interface with SD card.
1651 The ARM Versatile baseboard is emulated with the following devices:
1655 ARM926E, ARM1136 or Cortex-A8 CPU
1657 PL190 Vectored Interrupt Controller
1661 SMC 91c111 Ethernet adapter
1663 PL110 LCD controller
1665 PL050 KMI with PS/2 keyboard and mouse.
1667 PCI host bridge. Note the emulated PCI bridge only provides access to
1668 PCI memory space. It does not provide access to PCI IO space.
1669 This means some devices (eg. ne2k_pci NIC) are not usable, and others
1670 (eg. rtl8139 NIC) are only usable when the guest drivers use the memory
1671 mapped control registers.
1673 PCI OHCI USB controller.
1675 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices.
1677 PL181 MultiMedia Card Interface with SD card.
1680 Several variants of the ARM RealView baseboard are emulated,
1681 including the EB, PB-A8 and PBX-A9. Due to interactions with the
1682 bootloader, only certain Linux kernel configurations work out
1683 of the box on these boards.
1685 Kernels for the PB-A8 board should have CONFIG_REALVIEW_HIGH_PHYS_OFFSET
1686 enabled in the kernel, and expect 512M RAM. Kernels for The PBX-A9 board
1687 should have CONFIG_SPARSEMEM enabled, CONFIG_REALVIEW_HIGH_PHYS_OFFSET
1688 disabled and expect 1024M RAM.
1690 The following devices are emulated:
1694 ARM926E, ARM1136, ARM11MPCore, Cortex-A8 or Cortex-A9 MPCore CPU
1696 ARM AMBA Generic/Distributed Interrupt Controller
1700 SMC 91c111 or SMSC LAN9118 Ethernet adapter
1702 PL110 LCD controller
1704 PL050 KMI with PS/2 keyboard and mouse
1708 PCI OHCI USB controller
1710 LSI53C895A PCI SCSI Host Bus Adapter with hard disk and CD-ROM devices
1712 PL181 MultiMedia Card Interface with SD card.
1715 The XScale-based clamshell PDA models ("Spitz", "Akita", "Borzoi"
1716 and "Terrier") emulation includes the following peripherals:
1720 Intel PXA270 System-on-chip (ARM V5TE core)
1724 IBM/Hitachi DSCM microdrive in a PXA PCMCIA slot - not in "Akita"
1726 On-chip OHCI USB controller
1728 On-chip LCD controller
1730 On-chip Real Time Clock
1732 TI ADS7846 touchscreen controller on SSP bus
1734 Maxim MAX1111 analog-digital converter on I@math{^2}C bus
1736 GPIO-connected keyboard controller and LEDs
1738 Secure Digital card connected to PXA MMC/SD host
1742 WM8750 audio CODEC on I@math{^2}C and I@math{^2}S busses
1745 The Palm Tungsten|E PDA (codename "Cheetah") emulation includes the
1750 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
1752 ROM and RAM memories (ROM firmware image can be loaded with -option-rom)
1754 On-chip LCD controller
1756 On-chip Real Time Clock
1758 TI TSC2102i touchscreen controller / analog-digital converter / Audio
1759 CODEC, connected through MicroWire and I@math{^2}S busses
1761 GPIO-connected matrix keypad
1763 Secure Digital card connected to OMAP MMC/SD host
1768 Nokia N800 and N810 internet tablets (known also as RX-34 and RX-44 / 48)
1769 emulation supports the following elements:
1773 Texas Instruments OMAP2420 System-on-chip (ARM 1136 core)
1775 RAM and non-volatile OneNAND Flash memories
1777 Display connected to EPSON remote framebuffer chip and OMAP on-chip
1778 display controller and a LS041y3 MIPI DBI-C controller
1780 TI TSC2301 (in N800) and TI TSC2005 (in N810) touchscreen controllers
1781 driven through SPI bus
1783 National Semiconductor LM8323-controlled qwerty keyboard driven
1784 through I@math{^2}C bus
1786 Secure Digital card connected to OMAP MMC/SD host
1788 Three OMAP on-chip UARTs and on-chip STI debugging console
1790 A Bluetooth(R) transceiver and HCI connected to an UART
1792 Mentor Graphics "Inventra" dual-role USB controller embedded in a TI
1793 TUSB6010 chip - only USB host mode is supported
1795 TI TMP105 temperature sensor driven through I@math{^2}C bus
1797 TI TWL92230C power management companion with an RTC on I@math{^2}C bus
1799 Nokia RETU and TAHVO multi-purpose chips with an RTC, connected
1803 The Luminary Micro Stellaris LM3S811EVB emulation includes the following
1810 64k Flash and 8k SRAM.
1812 Timers, UARTs, ADC and I@math{^2}C interface.
1814 OSRAM Pictiva 96x16 OLED with SSD0303 controller on I@math{^2}C bus.
1817 The Luminary Micro Stellaris LM3S6965EVB emulation includes the following
1824 256k Flash and 64k SRAM.
1826 Timers, UARTs, ADC, I@math{^2}C and SSI interfaces.
1828 OSRAM Pictiva 128x64 OLED with SSD0323 controller connected via SSI.
1831 The Freecom MusicPal internet radio emulation includes the following
1836 Marvell MV88W8618 ARM core.
1838 32 MB RAM, 256 KB SRAM, 8 MB flash.
1842 MV88W8xx8 Ethernet controller
1844 MV88W8618 audio controller, WM8750 CODEC and mixer
1846 128×64 display with brightness control
1848 2 buttons, 2 navigation wheels with button function
1851 The Siemens SX1 models v1 and v2 (default) basic emulation.
1852 The emulation includes the following elements:
1856 Texas Instruments OMAP310 System-on-chip (ARM 925T core)
1858 ROM and RAM memories (ROM firmware image can be loaded with -pflash)
1860 1 Flash of 16MB and 1 Flash of 8MB
1864 On-chip LCD controller
1866 On-chip Real Time Clock
1868 Secure Digital card connected to OMAP MMC/SD host
1873 A Linux 2.6 test image is available on the QEMU web site. More
1874 information is available in the QEMU mailing-list archive.
1876 @c man begin OPTIONS
1878 The following options are specific to the ARM emulation:
1883 Enable semihosting syscall emulation.
1885 On ARM this implements the "Angel" interface.
1887 Note that this allows guest direct access to the host filesystem,
1888 so should only be used with trusted guest OS.
1894 @node ColdFire System emulator
1895 @section ColdFire System emulator
1896 @cindex system emulation (ColdFire)
1897 @cindex system emulation (M68K)
1899 Use the executable @file{qemu-system-m68k} to simulate a ColdFire machine.
1900 The emulator is able to boot a uClinux kernel.
1902 The M5208EVB emulation includes the following devices:
1906 MCF5208 ColdFire V2 Microprocessor (ISA A+ with EMAC).
1908 Three Two on-chip UARTs.
1910 Fast Ethernet Controller (FEC)
1913 The AN5206 emulation includes the following devices:
1917 MCF5206 ColdFire V2 Microprocessor.
1922 @c man begin OPTIONS
1924 The following options are specific to the ColdFire emulation:
1929 Enable semihosting syscall emulation.
1931 On M68K this implements the "ColdFire GDB" interface used by libgloss.
1933 Note that this allows guest direct access to the host filesystem,
1934 so should only be used with trusted guest OS.
1940 @node Cris System emulator
1941 @section Cris System emulator
1942 @cindex system emulation (Cris)
1946 @node Microblaze System emulator
1947 @section Microblaze System emulator
1948 @cindex system emulation (Microblaze)
1952 @node SH4 System emulator
1953 @section SH4 System emulator
1954 @cindex system emulation (SH4)
1958 @node Xtensa System emulator
1959 @section Xtensa System emulator
1960 @cindex system emulation (Xtensa)
1962 Two executables cover simulation of both Xtensa endian options,
1963 @file{qemu-system-xtensa} and @file{qemu-system-xtensaeb}.
1964 Two different machine types are emulated:
1968 Xtensa emulator pseudo board "sim"
1970 Avnet LX60/LX110/LX200 board
1973 The sim pseudo board emulation provides an environment similar
1974 to one provided by the proprietary Tensilica ISS.
1979 A range of Xtensa CPUs, default is the DC232B
1981 Console and filesystem access via semihosting calls
1984 The Avnet LX60/LX110/LX200 emulation supports:
1988 A range of Xtensa CPUs, default is the DC232B
1992 OpenCores 10/100 Mbps Ethernet MAC
1995 @c man begin OPTIONS
1997 The following options are specific to the Xtensa emulation:
2002 Enable semihosting syscall emulation.
2004 Xtensa semihosting provides basic file IO calls, such as open/read/write/seek/select.
2005 Tensilica baremetal libc for ISS and linux platform "sim" use this interface.
2007 Note that this allows guest direct access to the host filesystem,
2008 so should only be used with trusted guest OS.
2014 @node QEMU Guest Agent
2015 @chapter QEMU Guest Agent invocation
2017 @include qemu-ga.texi
2019 @node QEMU User space emulator
2020 @chapter QEMU User space emulator
2023 * Supported Operating Systems ::
2025 * Linux User space emulator::
2026 * BSD User space emulator ::
2029 @node Supported Operating Systems
2030 @section Supported Operating Systems
2032 The following OS are supported in user space emulation:
2036 Linux (referred as qemu-linux-user)
2038 BSD (referred as qemu-bsd-user)
2044 QEMU user space emulation has the following notable features:
2047 @item System call translation:
2048 QEMU includes a generic system call translator. This means that
2049 the parameters of the system calls can be converted to fix
2050 endianness and 32/64-bit mismatches between hosts and targets.
2051 IOCTLs can be converted too.
2053 @item POSIX signal handling:
2054 QEMU can redirect to the running program all signals coming from
2055 the host (such as @code{SIGALRM}), as well as synthesize signals from
2056 virtual CPU exceptions (for example @code{SIGFPE} when the program
2057 executes a division by zero).
2059 QEMU relies on the host kernel to emulate most signal system
2060 calls, for example to emulate the signal mask. On Linux, QEMU
2061 supports both normal and real-time signals.
2064 On Linux, QEMU can emulate the @code{clone} syscall and create a real
2065 host thread (with a separate virtual CPU) for each emulated thread.
2066 Note that not all targets currently emulate atomic operations correctly.
2067 x86 and ARM use a global lock in order to preserve their semantics.
2070 QEMU was conceived so that ultimately it can emulate itself. Although
2071 it is not very useful, it is an important test to show the power of the
2074 @node Linux User space emulator
2075 @section Linux User space emulator
2080 * Command line options::
2085 @subsection Quick Start
2087 In order to launch a Linux process, QEMU needs the process executable
2088 itself and all the target (x86) dynamic libraries used by it.
2092 @item On x86, you can just try to launch any process by using the native
2096 qemu-i386 -L / /bin/ls
2099 @code{-L /} tells that the x86 dynamic linker must be searched with a
2102 @item Since QEMU is also a linux process, you can launch QEMU with
2103 QEMU (NOTE: you can only do that if you compiled QEMU from the sources):
2106 qemu-i386 -L / qemu-i386 -L / /bin/ls
2109 @item On non x86 CPUs, you need first to download at least an x86 glibc
2110 (@file{qemu-runtime-i386-XXX-.tar.gz} on the QEMU web page). Ensure that
2111 @code{LD_LIBRARY_PATH} is not set:
2114 unset LD_LIBRARY_PATH
2117 Then you can launch the precompiled @file{ls} x86 executable:
2120 qemu-i386 tests/i386/ls
2122 You can look at @file{scripts/qemu-binfmt-conf.sh} so that
2123 QEMU is automatically launched by the Linux kernel when you try to
2124 launch x86 executables. It requires the @code{binfmt_misc} module in the
2127 @item The x86 version of QEMU is also included. You can try weird things such as:
2129 qemu-i386 /usr/local/qemu-i386/bin/qemu-i386 \
2130 /usr/local/qemu-i386/bin/ls-i386
2136 @subsection Wine launch
2140 @item Ensure that you have a working QEMU with the x86 glibc
2141 distribution (see previous section). In order to verify it, you must be
2145 qemu-i386 /usr/local/qemu-i386/bin/ls-i386
2148 @item Download the binary x86 Wine install
2149 (@file{qemu-XXX-i386-wine.tar.gz} on the QEMU web page).
2151 @item Configure Wine on your account. Look at the provided script
2152 @file{/usr/local/qemu-i386/@/bin/wine-conf.sh}. Your previous
2153 @code{$@{HOME@}/.wine} directory is saved to @code{$@{HOME@}/.wine.org}.
2155 @item Then you can try the example @file{putty.exe}:
2158 qemu-i386 /usr/local/qemu-i386/wine/bin/wine \
2159 /usr/local/qemu-i386/wine/c/Program\ Files/putty.exe
2164 @node Command line options
2165 @subsection Command line options
2168 @command{qemu-i386} [@option{-h]} [@option{-d]} [@option{-L} @var{path}] [@option{-s} @var{size}] [@option{-cpu} @var{model}] [@option{-g} @var{port}] [@option{-B} @var{offset}] [@option{-R} @var{size}] @var{program} [@var{arguments}...]
2175 Set the x86 elf interpreter prefix (default=/usr/local/qemu-i386)
2177 Set the x86 stack size in bytes (default=524288)
2179 Select CPU model (-cpu help for list and additional feature selection)
2180 @item -E @var{var}=@var{value}
2181 Set environment @var{var} to @var{value}.
2183 Remove @var{var} from the environment.
2185 Offset guest address by the specified number of bytes. This is useful when
2186 the address region required by guest applications is reserved on the host.
2187 This option is currently only supported on some hosts.
2189 Pre-allocate a guest virtual address space of the given size (in bytes).
2190 "G", "M", and "k" suffixes may be used when specifying the size.
2197 Activate logging of the specified items (use '-d help' for a list of log items)
2199 Act as if the host page size was 'pagesize' bytes
2201 Wait gdb connection to port
2203 Run the emulation in single step mode.
2206 Environment variables:
2210 Print system calls and arguments similar to the 'strace' program
2211 (NOTE: the actual 'strace' program will not work because the user
2212 space emulator hasn't implemented ptrace). At the moment this is
2213 incomplete. All system calls that don't have a specific argument
2214 format are printed with information for six arguments. Many
2215 flag-style arguments don't have decoders and will show up as numbers.
2218 @node Other binaries
2219 @subsection Other binaries
2221 @cindex user mode (Alpha)
2222 @command{qemu-alpha} TODO.
2224 @cindex user mode (ARM)
2225 @command{qemu-armeb} TODO.
2227 @cindex user mode (ARM)
2228 @command{qemu-arm} is also capable of running ARM "Angel" semihosted ELF
2229 binaries (as implemented by the arm-elf and arm-eabi Newlib/GDB
2230 configurations), and arm-uclinux bFLT format binaries.
2232 @cindex user mode (ColdFire)
2233 @cindex user mode (M68K)
2234 @command{qemu-m68k} is capable of running semihosted binaries using the BDM
2235 (m5xxx-ram-hosted.ld) or m68k-sim (sim.ld) syscall interfaces, and
2236 coldfire uClinux bFLT format binaries.
2238 The binary format is detected automatically.
2240 @cindex user mode (Cris)
2241 @command{qemu-cris} TODO.
2243 @cindex user mode (i386)
2244 @command{qemu-i386} TODO.
2245 @command{qemu-x86_64} TODO.
2247 @cindex user mode (Microblaze)
2248 @command{qemu-microblaze} TODO.
2250 @cindex user mode (MIPS)
2251 @command{qemu-mips} TODO.
2252 @command{qemu-mipsel} TODO.
2254 @cindex user mode (NiosII)
2255 @command{qemu-nios2} TODO.
2257 @cindex user mode (PowerPC)
2258 @command{qemu-ppc64abi32} TODO.
2259 @command{qemu-ppc64} TODO.
2260 @command{qemu-ppc} TODO.
2262 @cindex user mode (SH4)
2263 @command{qemu-sh4eb} TODO.
2264 @command{qemu-sh4} TODO.
2266 @cindex user mode (SPARC)
2267 @command{qemu-sparc} can execute Sparc32 binaries (Sparc32 CPU, 32 bit ABI).
2269 @command{qemu-sparc32plus} can execute Sparc32 and SPARC32PLUS binaries
2270 (Sparc64 CPU, 32 bit ABI).
2272 @command{qemu-sparc64} can execute some Sparc64 (Sparc64 CPU, 64 bit ABI) and
2273 SPARC32PLUS binaries (Sparc64 CPU, 32 bit ABI).
2275 @node BSD User space emulator
2276 @section BSD User space emulator
2281 * BSD Command line options::
2285 @subsection BSD Status
2289 target Sparc64 on Sparc64: Some trivial programs work.
2292 @node BSD Quick Start
2293 @subsection Quick Start
2295 In order to launch a BSD process, QEMU needs the process executable
2296 itself and all the target dynamic libraries used by it.
2300 @item On Sparc64, you can just try to launch any process by using the native
2304 qemu-sparc64 /bin/ls
2309 @node BSD Command line options
2310 @subsection Command line options
2313 @command{qemu-sparc64} [@option{-h]} [@option{-d]} [@option{-L} @var{path}] [@option{-s} @var{size}] [@option{-bsd} @var{type}] @var{program} [@var{arguments}...]
2320 Set the library root path (default=/)
2322 Set the stack size in bytes (default=524288)
2323 @item -ignore-environment
2324 Start with an empty environment. Without this option,
2325 the initial environment is a copy of the caller's environment.
2326 @item -E @var{var}=@var{value}
2327 Set environment @var{var} to @var{value}.
2329 Remove @var{var} from the environment.
2331 Set the type of the emulated BSD Operating system. Valid values are
2332 FreeBSD, NetBSD and OpenBSD (default).
2339 Activate logging of the specified items (use '-d help' for a list of log items)
2341 Act as if the host page size was 'pagesize' bytes
2343 Run the emulation in single step mode.
2347 @include qemu-tech.texi
2349 @node Deprecated features
2350 @appendix Deprecated features
2352 In general features are intended to be supported indefinitely once
2353 introduced into QEMU. In the event that a feature needs to be removed,
2354 it will be listed in this appendix. The feature will remain functional
2355 for 2 releases prior to actual removal. Deprecated features may also
2356 generate warnings on the console when QEMU starts up, or if activated
2357 via a monitor command, however, this is not a mandatory requirement.
2359 Prior to the 2.10.0 release there was no official policy on how
2360 long features would be deprecated prior to their removal, nor
2361 any documented list of which features were deprecated. Thus
2362 any features deprecated prior to 2.10.0 will be treated as if
2363 they were first deprecated in the 2.10.0 release.
2365 What follows is a list of all features currently marked as
2368 @section System emulator command line arguments
2370 @subsection -drive boot=on|off (since 1.3.0)
2372 The ``boot=on|off'' option to the ``-drive'' argument is
2373 ignored. Applications should use the ``bootindex=N'' parameter
2374 to set an absolute ordering between devices instead.
2376 @subsection -tdf (since 1.3.0)
2378 The ``-tdf'' argument is ignored. The behaviour implemented
2379 by this argument is now the default when using the KVM PIT,
2380 but can be requested explicitly using
2381 ``-global kvm-pit.lost_tick_policy=slew''.
2383 @subsection -no-kvm-pit-reinjection (since 1.3.0)
2385 The ``-no-kvm-pit-reinjection'' argument is now a
2386 synonym for setting ``-global kvm-pit.lost_tick_policy=discard''.
2388 @subsection -no-kvm-irqchip (since 1.3.0)
2390 The ``-no-kvm-irqchip'' argument is now a synonym for
2391 setting ``-machine kernel_irqchip=off''.
2393 @subsection -no-kvm-pit (since 1.3.0)
2395 The ``-no-kvm-pit'' argument is ignored. It is no longer
2396 possible to disable the KVM PIT directly.
2398 @subsection -no-kvm (since 1.3.0)
2400 The ``-no-kvm'' argument is now a synonym for setting
2401 ``-machine accel=tcg''.
2403 @subsection -mon default=on (since 2.4.0)
2405 The ``default'' option to the ``-mon'' argument is
2406 now ignored. When multiple monitors were enabled, it
2407 indicated which monitor would receive log messages
2408 from the various subsystems. This feature is no longer
2409 required as messages are now only sent to the monitor
2410 in response to explicitly monitor commands.
2412 @subsection -vnc tls (since 2.5.0)
2414 The ``-vnc tls'' argument is now a synonym for setting
2415 ``-object tls-creds-anon,id=tls0'' combined with
2416 ``-vnc tls-creds=tls0'
2418 @subsection -vnc x509 (since 2.5.0)
2420 The ``-vnc x509=/path/to/certs'' argument is now a
2422 ``-object tls-creds-x509,dir=/path/to/certs,id=tls0,verify-peer=no''
2423 combined with ``-vnc tls-creds=tls0'
2425 @subsection -vnc x509verify (since 2.5.0)
2427 The ``-vnc x509verify=/path/to/certs'' argument is now a
2429 ``-object tls-creds-x509,dir=/path/to/certs,id=tls0,verify-peer=yes''
2430 combined with ``-vnc tls-creds=tls0'
2432 @subsection -tftp (since 2.6.0)
2434 The ``-tftp /some/dir'' argument is now a synonym for setting
2435 the ``-netdev user,tftp=/some/dir' argument. The new syntax
2436 allows different settings to be provided per NIC.
2438 @subsection -bootp (since 2.6.0)
2440 The ``-bootp /some/file'' argument is now a synonym for setting
2441 the ``-netdev user,bootp=/some/file' argument. The new syntax
2442 allows different settings to be provided per NIC.
2444 @subsection -redir (since 2.6.0)
2446 The ``-redir ARGS'' argument is now a synonym for setting
2447 the ``-netdev user,hostfwd=ARGS'' argument instead. The new
2448 syntax allows different settings to be provided per NIC.
2450 @subsection -smb (since 2.6.0)
2452 The ``-smb /some/dir'' argument is now a synonym for setting
2453 the ``-netdev user,smb=/some/dir'' argument instead. The new
2454 syntax allows different settings to be provided per NIC.
2456 @subsection -net channel (since 2.6.0)
2458 The ``--net channel,ARGS'' argument is now a synonym for setting
2459 the ``-netdev user,guestfwd=ARGS'' argument instead.
2461 @subsection -net vlan (since 2.9.0)
2463 The ``-net vlan=NN'' argument is partially replaced with the
2464 new ``-netdev'' argument. The remaining use cases will no
2465 longer be directly supported in QEMU.
2467 @subsection -drive if=scsi (since 2.9.0)
2469 The ``-drive if=scsi'' argument is replaced by the the
2470 ``-device BUS-TYPE'' argument combined with ``-drive if=none''.
2472 @subsection -net dump (since 2.10.0)
2474 The ``--net dump'' argument is now replaced with the
2475 ``-object filter-dump'' argument which works in combination
2476 with the modern ``-netdev`` backends instead.
2478 @subsection -hdachs (since 2.10.0)
2480 The ``-hdachs'' argument is now a synonym for setting
2481 the ``cyls'', ``heads'', ``secs'', and ``trans'' properties
2482 on the ``ide-hd'' device using the ``-device'' argument.
2483 The new syntax allows different settings to be provided
2486 @subsection -usbdevice (since 2.10.0)
2488 The ``-usbdevice DEV'' argument is now a synonym for setting
2489 the ``-device usb-DEV'' argument instead. The deprecated syntax
2490 would automatically enable USB support on the machine type.
2491 If using the new syntax, USB support must be explicitly
2492 enabled via the ``-machine usb=on'' argument.
2494 @subsection -nodefconfig (since 2.11.0)
2496 The ``-nodefconfig`` argument is a synonym for ``-no-user-config``.
2498 @section qemu-img command line arguments
2500 @subsection convert -s (since 2.0.0)
2502 The ``convert -s snapshot_id_or_name'' argument is obsoleted
2503 by the ``convert -l snapshot_param'' argument instead.
2505 @section System emulator human monitor commands
2507 @subsection host_net_add (since 2.10.0)
2509 The ``host_net_add'' command is replaced by the ``netdev_add'' command.
2511 @subsection host_net_remove (since 2.10.0)
2513 The ``host_net_remove'' command is replaced by the ``netdev_del'' command.
2515 @subsection usb_add (since 2.10.0)
2517 The ``usb_add'' command is replaced by the ``device_add'' command.
2519 @subsection usb_del (since 2.10.0)
2521 The ``usb_del'' command is replaced by the ``device_del'' command.
2523 @section System emulator devices
2525 @subsection ivshmem (since 2.6.0)
2527 The ``ivshmem'' device type is replaced by either the ``ivshmem-plain''
2528 or ``ivshmem-doorbell`` device types.
2530 @subsection spapr-pci-vfio-host-bridge (since 2.6.0)
2532 The ``spapr-pci-vfio-host-bridge'' device type is replaced by
2533 the ``spapr-pci-host-bridge'' device type.
2538 QEMU is a trademark of Fabrice Bellard.
2540 QEMU is released under the
2541 @url{https://www.gnu.org/licenses/gpl-2.0.txt,GNU General Public License},
2542 version 2. Parts of QEMU have specific licenses, see file
2543 @url{http://git.qemu.org/?p=qemu.git;a=blob_plain;f=LICENSE,LICENSE}.
2557 @section Concept Index
2558 This is the main index. Should we combine all keywords in one index? TODO
2561 @node Function Index
2562 @section Function Index
2563 This index could be used for command line options and monitor functions.
2566 @node Keystroke Index
2567 @section Keystroke Index
2569 This is a list of all keystrokes which have a special function
2570 in system emulation.
2575 @section Program Index
2578 @node Data Type Index
2579 @section Data Type Index
2581 This index could be used for qdev device names and options.
2585 @node Variable Index
2586 @section Variable Index