qemu-doc: split qemu-doc.texi in multiple files

In order to facilitate the reorganization of qemu-doc.texi content,
as well as the conversion to rST/Sphinx, split it in multiple .texi
files that are included from docs/system.

The "other devices" section is renamed to ivshmem and placed last.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Tested-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 20200228153619.9906-6-peter.maydell@linaro.org
Message-id: 20200226113034.6741-6-pbonzini@redhat.com
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

15 files changed, 1450 insertions, 0 deletions

diff --git a/docs/system/build-platforms.texi b/docs/system/build-platforms.texi
new file mode 100644
index 0000000000..531ef5bed4
--- /dev/null
+++ b/docs/system/build-platforms.texi
@@ -0,0 +1,67 @@
+@node Supported build platforms
+@appendix Supported build platforms
+
+QEMU aims to support building and executing on multiple host OS platforms.
+This appendix outlines which platforms are the major build targets. These
+platforms are used as the basis for deciding upon the minimum required
+versions of 3rd party software QEMU depends on. The supported platforms
+are the targets for automated testing performed by the project when patches
+are submitted for review, and tested before and after merge.
+
+If a platform is not listed here, it does not imply that QEMU won't work.
+If an unlisted platform has comparable software versions to a listed platform,
+there is every expectation that it will work. Bug reports are welcome for
+problems encountered on unlisted platforms unless they are clearly older
+vintage than what is described here.
+
+Note that when considering software versions shipped in distros as support
+targets, QEMU considers only the version number, and assumes the features in
+that distro match the upstream release with the same version. In other words,
+if a distro backports extra features to the software in their distro, QEMU
+upstream code will not add explicit support for those backports, unless the
+feature is auto-detectable in a manner that works for the upstream releases
+too.
+
+The Repology site @url{https://repology.org} is a useful resource to identify
+currently shipped versions of software in various operating systems, though
+it does not cover all distros listed below.
+
+@section Linux OS
+
+For distributions with frequent, short-lifetime releases, the project will
+aim to support all versions that are not end of life by their respective
+vendors. For the purposes of identifying supported software versions, the
+project will look at Fedora, Ubuntu, and openSUSE distros. Other short-
+lifetime distros will be assumed to ship similar software versions.
+
+For distributions with long-lifetime releases, the project will aim to support
+the most recent major version at all times. Support for the previous major
+version will be dropped 2 years after the new major version is released,
+or when it reaches ``end of life''. For the purposes of identifying
+supported software versions, the project will look at RHEL, Debian,
+Ubuntu LTS, and SLES distros. Other long-lifetime distros will be
+assumed to ship similar software versions.
+
+@section Windows
+
+The project supports building with current versions of the MinGW toolchain,
+hosted on Linux.
+
+@section macOS
+
+The project supports building with the two most recent versions of macOS, with
+the current homebrew package set available.
+
+@section FreeBSD
+
+The project aims to support the all the versions which are not end of life.
+
+@section NetBSD
+
+The project aims to support the most recent major version at all times. Support
+for the previous major version will be dropped 2 years after the new major
+version is released.
+
+@section OpenBSD
+
+The project aims to support the all the versions which are not end of life.
diff --git a/docs/system/gdb.texi b/docs/system/gdb.texi
new file mode 100644
index 0000000000..f49bc5891e
--- /dev/null
+++ b/docs/system/gdb.texi
@@ -0,0 +1,71 @@
+@node gdb_usage
+@section GDB usage
+
+QEMU has a primitive support to work with gdb, so that you can do
+'Ctrl-C' while the virtual machine is running and inspect its state.
+
+In order to use gdb, launch QEMU with the '-s' option. It will wait for a
+gdb connection:
+@example
+@value{qemu_system} -s -kernel bzImage -hda rootdisk.img -append "root=/dev/hda"
+Connected to host network interface: tun0
+Waiting gdb connection on port 1234
+@end example
+
+Then launch gdb on the 'vmlinux' executable:
+@example
+> gdb vmlinux
+@end example
+
+In gdb, connect to QEMU:
+@example
+(gdb) target remote localhost:1234
+@end example
+
+Then you can use gdb normally. For example, type 'c' to launch the kernel:
+@example
+(gdb) c
+@end example
+
+Here are some useful tips in order to use gdb on system code:
+
+@enumerate
+@item
+Use @code{info reg} to display all the CPU registers.
+@item
+Use @code{x/10i $eip} to display the code at the PC position.
+@item
+Use @code{set architecture i8086} to dump 16 bit code. Then use
+@code{x/10i $cs*16+$eip} to dump the code at the PC position.
+@end enumerate
+
+Advanced debugging options:
+
+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:
+@table @code
+@item maintenance packet qqemu.sstepbits
+
+This will display the MASK bits used to control the single stepping IE:
+@example
+(gdb) maintenance packet qqemu.sstepbits
+sending: "qqemu.sstepbits"
+received: "ENABLE=1,NOIRQ=2,NOTIMER=4"
+@end example
+@item maintenance packet qqemu.sstep
+
+This will display the current value of the mask used when single stepping IE:
+@example
+(gdb) maintenance packet qqemu.sstep
+sending: "qqemu.sstep"
+received: "0x7"
+@end example
+@item maintenance packet Qqemu.sstep=HEX_VALUE
+
+This will change the single step mask, so if wanted to enable IRQs on the single step, but not timers, you would use:
+@example
+(gdb) maintenance packet Qqemu.sstep=0x5
+sending: "qemu.sstep=0x5"
+received: "OK"
+@end example
+@end table
+
diff --git a/docs/system/images.texi b/docs/system/images.texi
new file mode 100644
index 0000000000..c5060348ec
--- /dev/null
+++ b/docs/system/images.texi
@@ -0,0 +1,88 @@
+@node disk_images
+@section Disk Images
+
+QEMU supports many disk image formats, including growable disk images
+(their size increase as non empty sectors are written), compressed and
+encrypted disk images.
+
+@menu
+* disk_images_quickstart::    Quick start for disk image creation
+* disk_images_snapshot_mode:: Snapshot mode
+* vm_snapshots::              VM snapshots
+@end menu
+
+@node disk_images_quickstart
+@subsection Quick start for disk image creation
+
+You can create a disk image with the command:
+@example
+qemu-img create myimage.img mysize
+@end example
+where @var{myimage.img} is the disk image filename and @var{mysize} is its
+size in kilobytes. You can add an @code{M} suffix to give the size in
+megabytes and a @code{G} suffix for gigabytes.
+
+@c When this document is converted to rst we should make this into
+@c a proper linked reference to the qemu-img documentation again:
+See the qemu-img invocation documentation for more information.
+
+@node disk_images_snapshot_mode
+@subsection Snapshot mode
+
+If you use the option @option{-snapshot}, all disk images are
+considered as read only. When sectors in written, they are written in
+a temporary file created in @file{/tmp}. You can however force the
+write back to the raw disk images by using the @code{commit} monitor
+command (or @key{C-a s} in the serial console).
+
+@node vm_snapshots
+@subsection VM snapshots
+
+VM snapshots are snapshots of the complete virtual machine including
+CPU state, RAM, device state and the content of all the writable
+disks. In order to use VM snapshots, you must have at least one non
+removable and writable block device using the @code{qcow2} disk image
+format. Normally this device is the first virtual hard drive.
+
+Use the monitor command @code{savevm} to create a new VM snapshot or
+replace an existing one. A human readable name can be assigned to each
+snapshot in addition to its numerical ID.
+
+Use @code{loadvm} to restore a VM snapshot and @code{delvm} to remove
+a VM snapshot. @code{info snapshots} lists the available snapshots
+with their associated information:
+
+@example
+(qemu) info snapshots
+Snapshot devices: hda
+Snapshot list (from hda):
+ID        TAG                 VM SIZE                DATE       VM CLOCK
+1         start                   41M 2006-08-06 12:38:02   00:00:14.954
+2                                 40M 2006-08-06 12:43:29   00:00:18.633
+3         msys                    40M 2006-08-06 12:44:04   00:00:23.514
+@end example
+
+A VM snapshot is made of a VM state info (its size is shown in
+@code{info snapshots}) and a snapshot of every writable disk image.
+The VM state info is stored in the first @code{qcow2} non removable
+and writable block device. The disk image snapshots are stored in
+every disk image. The size of a snapshot in a disk image is difficult
+to evaluate and is not shown by @code{info snapshots} because the
+associated disk sectors are shared among all the snapshots to save
+disk space (otherwise each snapshot would need a full copy of all the
+disk images).
+
+When using the (unrelated) @code{-snapshot} option
+(@ref{disk_images_snapshot_mode}), you can always make VM snapshots,
+but they are deleted as soon as you exit QEMU.
+
+VM snapshots currently have the following known limitations:
+@itemize
+@item
+They cannot cope with removable devices if they are removed or
+inserted after a snapshot is done.
+@item
+A few device drivers still have incomplete snapshot support so their
+state is not saved or restored properly (in particular USB).
+@end itemize
+
diff --git a/docs/system/invocation.texi b/docs/system/invocation.texi
new file mode 100644
index 0000000000..dac41cc7e5
--- /dev/null
+++ b/docs/system/invocation.texi
@@ -0,0 +1,240 @@
+@node sec_invocation
+@section Invocation
+
+@example
+@c man begin SYNOPSIS
+@command{@value{qemu_system}} [@var{options}] [@var{disk_image}]
+@c man end
+@end example
+
+@c man begin OPTIONS
+@var{disk_image} is a raw hard disk image for IDE hard disk 0. Some
+targets do not need a disk image.
+
+@include qemu-options.texi
+
+@c man end
+
+@subsection Device URL Syntax
+@c TODO merge this with section Disk Images
+
+@c man begin NOTES
+
+In addition to using normal file images for the emulated storage devices,
+QEMU can also use networked resources such as iSCSI devices. These are
+specified using a special URL syntax.
+
+@table @option
+@item iSCSI
+iSCSI support allows QEMU to access iSCSI resources directly and use as
+images for the guest storage. Both disk and cdrom images are supported.
+
+Syntax for specifying iSCSI LUNs is
+``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
+
+By default qemu will use the iSCSI initiator-name
+'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
+line or a configuration file.
+
+Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
+stalled requests and force a reestablishment of the session. The timeout
+is specified in seconds. The default is 0 which means no timeout. Libiscsi
+1.15.0 or greater is required for this feature.
+
+Example (without authentication):
+@example
+@value{qemu_system} -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
+                 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
+                 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
+@end example
+
+Example (CHAP username/password via URL):
+@example
+@value{qemu_system} -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
+@end example
+
+Example (CHAP username/password via environment variables):
+@example
+LIBISCSI_CHAP_USERNAME="user" \
+LIBISCSI_CHAP_PASSWORD="password" \
+@value{qemu_system} -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
+@end example
+
+@item NBD
+QEMU supports NBD (Network Block Devices) both using TCP protocol as well
+as Unix Domain Sockets.  With TCP, the default port is 10809.
+
+Syntax for specifying a NBD device using TCP, in preferred URI form:
+``nbd://<server-ip>[:<port>]/[<export>]''
+
+Syntax for specifying a NBD device using Unix Domain Sockets; remember
+that '?' is a shell glob character and may need quoting:
+``nbd+unix:///[<export>]?socket=<domain-socket>''
+
+Older syntax that is also recognized:
+``nbd:<server-ip>:<port>[:exportname=<export>]''
+
+Syntax for specifying a NBD device using Unix Domain Sockets
+``nbd:unix:<domain-socket>[:exportname=<export>]''
+
+Example for TCP
+@example
+@value{qemu_system} --drive file=nbd:192.0.2.1:30000
+@end example
+
+Example for Unix Domain Sockets
+@example
+@value{qemu_system} --drive file=nbd:unix:/tmp/nbd-socket
+@end example
+
+@item SSH
+QEMU supports SSH (Secure Shell) access to remote disks.
+
+Examples:
+@example
+@value{qemu_system} -drive file=ssh://user@@host/path/to/disk.img
+@value{qemu_system} -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
+@end example
+
+Currently authentication must be done using ssh-agent.  Other
+authentication methods may be supported in future.
+
+@item Sheepdog
+Sheepdog is a distributed storage system for QEMU.
+QEMU supports using either local sheepdog devices or remote networked
+devices.
+
+Syntax for specifying a sheepdog device
+@example
+sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
+@end example
+
+Example
+@example
+@value{qemu_system} --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
+@end example
+
+See also @url{https://sheepdog.github.io/sheepdog/}.
+
+@item GlusterFS
+GlusterFS is a user space distributed file system.
+QEMU supports the use of GlusterFS volumes for hosting VM disk images using
+TCP, Unix Domain Sockets and RDMA transport protocols.
+
+Syntax for specifying a VM disk image on GlusterFS volume is
+@example
+
+URI:
+gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...]
+
+JSON:
+'json:@{"driver":"qcow2","file":@{"driver":"gluster","volume":"testvol","path":"a.img","debug":N,"logfile":"...",
+@                                 "server":[@{"type":"tcp","host":"...","port":"..."@},
+@                                           @{"type":"unix","socket":"..."@}]@}@}'
+@end example
+
+
+Example
+@example
+URI:
+@value{qemu_system} --drive file=gluster://192.0.2.1/testvol/a.img,
+@                               file.debug=9,file.logfile=/var/log/qemu-gluster.log
+
+JSON:
+@value{qemu_system} 'json:@{"driver":"qcow2",
+@                          "file":@{"driver":"gluster",
+@                                   "volume":"testvol","path":"a.img",
+@                                   "debug":9,"logfile":"/var/log/qemu-gluster.log",
+@                                   "server":[@{"type":"tcp","host":"1.2.3.4","port":24007@},
+@                                             @{"type":"unix","socket":"/var/run/glusterd.socket"@}]@}@}'
+@value{qemu_system} -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img,
+@                                      file.debug=9,file.logfile=/var/log/qemu-gluster.log,
+@                                      file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007,
+@                                      file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket
+@end example
+
+See also @url{http://www.gluster.org}.
+
+@item HTTP/HTTPS/FTP/FTPS
+QEMU supports read-only access to files accessed over http(s) and ftp(s).
+
+Syntax using a single filename:
+@example
+<protocol>://[<username>[:<password>]@@]<host>/<path>
+@end example
+
+where:
+@table @option
+@item protocol
+'http', 'https', 'ftp', or 'ftps'.
+
+@item username
+Optional username for authentication to the remote server.
+
+@item password
+Optional password for authentication to the remote server.
+
+@item host
+Address of the remote server.
+
+@item path
+Path on the remote server, including any query string.
+@end table
+
+The following options are also supported:
+@table @option
+@item url
+The full URL when passing options to the driver explicitly.
+
+@item readahead
+The amount of data to read ahead with each range request to the remote server.
+This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
+does not have a suffix, it will be assumed to be in bytes. The value must be a
+multiple of 512 bytes. It defaults to 256k.
+
+@item sslverify
+Whether to verify the remote server's certificate when connecting over SSL. It
+can have the value 'on' or 'off'. It defaults to 'on'.
+
+@item cookie
+Send this cookie (it can also be a list of cookies separated by ';') with
+each outgoing request.  Only supported when using protocols such as HTTP
+which support cookies, otherwise ignored.
+
+@item timeout
+Set the timeout in seconds of the CURL connection. This timeout is the time
+that CURL waits for a response from the remote server to get the size of the
+image to be downloaded. If not set, the default timeout of 5 seconds is used.
+@end table
+
+Note that when passing options to qemu explicitly, @option{driver} is the value
+of <protocol>.
+
+Example: boot from a remote Fedora 20 live ISO image
+@example
+@value{qemu_system_x86} --drive media=cdrom,file=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
+
+@value{qemu_system_x86} --drive media=cdrom,file.driver=http,file.url=http://archives.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
+@end example
+
+Example: boot from a remote Fedora 20 cloud image using a local overlay for
+writes, copy-on-read, and a readahead of 64k
+@example
+qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"http",, "file.url":"http://archives.fedoraproject.org/pub/archive/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2
+
+@value{qemu_system_x86} -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
+@end example
+
+Example: boot from an image stored on a VMware vSphere server with a self-signed
+certificate using a local overlay for writes, a readahead of 64k and a timeout
+of 10 seconds.
+@example
+qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k",, "file.timeout":10@}' /tmp/test.qcow2
+
+@value{qemu_system_x86} -drive file=/tmp/test.qcow2
+@end example
+
+@end table
+
+@c man end
+
diff --git a/docs/system/ivshmem.texi b/docs/system/ivshmem.texi
new file mode 100644
index 0000000000..bd97719eaf
--- /dev/null
+++ b/docs/system/ivshmem.texi
@@ -0,0 +1,60 @@
+@node pcsys_ivshmem
+@section Inter-VM Shared Memory device
+
+On Linux hosts, a shared memory device is available.  The basic syntax
+is:
+
+@example
+@value{qemu_system_x86} -device ivshmem-plain,memdev=@var{hostmem}
+@end example
+
+where @var{hostmem} names a host memory backend.  For a POSIX shared
+memory backend, use something like
+
+@example
+-object memory-backend-file,size=1M,share,mem-path=/dev/shm/ivshmem,id=@var{hostmem}
+@end example
+
+If desired, interrupts can be sent between guest VMs accessing the same shared
+memory region.  Interrupt support requires using a shared memory server and
+using a chardev socket to connect to it.  The code for the shared memory server
+is qemu.git/contrib/ivshmem-server.  An example syntax when using the shared
+memory server is:
+
+@example
+# First start the ivshmem server once and for all
+ivshmem-server -p @var{pidfile} -S @var{path} -m @var{shm-name} -l @var{shm-size} -n @var{vectors}
+
+# Then start your qemu instances with matching arguments
+@value{qemu_system_x86} -device ivshmem-doorbell,vectors=@var{vectors},chardev=@var{id}
+                 -chardev socket,path=@var{path},id=@var{id}
+@end example
+
+When using the server, the guest will be assigned a VM ID (>=0) that allows guests
+using the same server to communicate via interrupts.  Guests can read their
+VM ID from a device register (see ivshmem-spec.txt).
+
+@subsection Migration with ivshmem
+
+With device property @option{master=on}, the guest will copy the shared
+memory on migration to the destination host.  With @option{master=off},
+the guest will not be able to migrate with the device attached.  In the
+latter case, the device should be detached and then reattached after
+migration using the PCI hotplug support.
+
+At most one of the devices sharing the same memory can be master.  The
+master must complete migration before you plug back the other devices.
+
+@subsection ivshmem and hugepages
+
+Instead of specifying the <shm size> using POSIX shm, you may specify
+a memory backend that has hugepage support:
+
+@example
+@value{qemu_system_x86} -object memory-backend-file,size=1G,mem-path=/dev/hugepages/my-shmem-file,share,id=mb1
+                 -device ivshmem-plain,memdev=mb1
+@end example
+
+ivshmem-server also supports hugepages mount points with the
+@option{-m} memory path argument.
+
diff --git a/docs/system/keys.texi b/docs/system/keys.texi
new file mode 100644
index 0000000000..4c74b3bf4d
--- /dev/null
+++ b/docs/system/keys.texi
@@ -0,0 +1,53 @@
+@node pcsys_keys
+@section Keys in the graphical frontends
+
+@c man begin OPTIONS
+
+During the graphical emulation, you can use special key combinations to change
+modes. The default key mappings are shown below, but if you use @code{-alt-grab}
+then the modifier is Ctrl-Alt-Shift (instead of Ctrl-Alt) and if you use
+@code{-ctrl-grab} then the modifier is the right Ctrl key (instead of Ctrl-Alt):
+
+@table @key
+@item Ctrl-Alt-f
+@kindex Ctrl-Alt-f
+Toggle full screen
+
+@item Ctrl-Alt-+
+@kindex Ctrl-Alt-+
+Enlarge the screen
+
+@item Ctrl-Alt--
+@kindex Ctrl-Alt--
+Shrink the screen
+
+@item Ctrl-Alt-u
+@kindex Ctrl-Alt-u
+Restore the screen's un-scaled dimensions
+
+@item Ctrl-Alt-n
+@kindex Ctrl-Alt-n
+Switch to virtual console 'n'. Standard console mappings are:
+@table @emph
+@item 1
+Target system display
+@item 2
+Monitor
+@item 3
+Serial port
+@end table
+
+@item Ctrl-Alt
+@kindex Ctrl-Alt
+Toggle mouse and keyboard grab.
+@end table
+
+@kindex Ctrl-Up
+@kindex Ctrl-Down
+@kindex Ctrl-PageUp
+@kindex Ctrl-PageDown
+In the virtual consoles, you can use @key{Ctrl-Up}, @key{Ctrl-Down},
+@key{Ctrl-PageUp} and @key{Ctrl-PageDown} to move in the back log.
+
+@c man end
+
diff --git a/docs/system/license.texi b/docs/system/license.texi
new file mode 100644
index 0000000000..b682235a7e
--- /dev/null
+++ b/docs/system/license.texi
@@ -0,0 +1,9 @@
+@node License
+@appendix License
+
+QEMU is a trademark of Fabrice Bellard.
+
+QEMU is released under the
+@url{https://www.gnu.org/licenses/gpl-2.0.txt,GNU General Public License},
+version 2. Parts of QEMU have specific licenses, see file
+@url{https://git.qemu.org/?p=qemu.git;a=blob_plain;f=LICENSE,LICENSE}.
diff --git a/docs/system/linuxboot.texi b/docs/system/linuxboot.texi
new file mode 100644
index 0000000000..97c3cefae0
--- /dev/null
+++ b/docs/system/linuxboot.texi
@@ -0,0 +1,27 @@
+@node direct_linux_boot
+@section Direct Linux Boot
+
+This section explains how to launch a Linux kernel inside QEMU without
+having to make a full bootable image. It is very useful for fast Linux
+kernel testing.
+
+The syntax is:
+@example
+@value{qemu_system} -kernel bzImage -hda rootdisk.img -append "root=/dev/hda"
+@end example
+
+Use @option{-kernel} to provide the Linux kernel image and
+@option{-append} to give the kernel command line arguments. The
+@option{-initrd} option can be used to provide an INITRD image.
+
+If you do not need graphical output, you can disable it and redirect
+the virtual serial port and the QEMU monitor to the console with the
+@option{-nographic} option. The typical command line is:
+@example
+@value{qemu_system} -kernel bzImage -hda rootdisk.img \
+                 -append "root=/dev/hda console=ttyS0" -nographic
+@end example
+
+Use @key{Ctrl-a c} to switch between the serial console and the
+monitor (@pxref{pcsys_keys}).
+
diff --git a/docs/system/monitor.texi b/docs/system/monitor.texi
new file mode 100644
index 0000000000..c5b6a9b38e
--- /dev/null
+++ b/docs/system/monitor.texi
@@ -0,0 +1,35 @@
+@node pcsys_monitor
+@section QEMU Monitor
+@cindex QEMU monitor
+
+The QEMU monitor is used to give complex commands to the QEMU
+emulator. You can use it to:
+
+@itemize @minus
+
+@item
+Remove or insert removable media images
+(such as CD-ROM or floppies).
+
+@item
+Freeze/unfreeze the Virtual Machine (VM) and save or restore its state
+from a disk file.
+
+@item Inspect the VM state without an external debugger.
+
+@end itemize
+
+@subsection Commands
+
+The following commands are available:
+
+@include qemu-monitor.texi
+
+@include qemu-monitor-info.texi
+
+@subsection Integer expressions
+
+The monitor understands integers expressions for every integer
+argument. You can use register names to get the value of specifics
+CPU registers by prefixing them with @emph{$}.
+
diff --git a/docs/system/mux-chardev.texi b/docs/system/mux-chardev.texi
new file mode 100644
index 0000000000..c9a2d14cb8
--- /dev/null
+++ b/docs/system/mux-chardev.texi
@@ -0,0 +1,51 @@
+@node mux_keys
+@section Keys in the character backend multiplexer
+
+@c man begin OPTIONS
+
+During emulation, if you are using a character backend multiplexer
+(which is the default if you are using @option{-nographic}) then
+several commands are available via an escape sequence. These
+key sequences all start with an escape character, which is @key{Ctrl-a}
+by default, but can be changed with @option{-echr}. The list below assumes
+you're using the default.
+
+@table @key
+@item Ctrl-a h
+@kindex Ctrl-a h
+Print this help
+@item Ctrl-a x
+@kindex Ctrl-a x
+Exit emulator
+@item Ctrl-a s
+@kindex Ctrl-a s
+Save disk data back to file (if -snapshot)
+@item Ctrl-a t
+@kindex Ctrl-a t
+Toggle console timestamps
+@item Ctrl-a b
+@kindex Ctrl-a b
+Send break (magic sysrq in Linux)
+@item Ctrl-a c
+@kindex Ctrl-a c
+Rotate between the frontends connected to the multiplexer (usually
+this switches between the monitor and the console)
+@item Ctrl-a Ctrl-a
+@kindex Ctrl-a Ctrl-a
+Send the escape character to the frontend
+@end table
+@c man end
+
+@ignore
+
+@c man begin SEEALSO
+The HTML documentation of QEMU for more precise information and Linux
+user mode emulator invocation.
+@c man end
+
+@c man begin AUTHOR
+Fabrice Bellard
+@c man end
+
+@end ignore
+
diff --git a/docs/system/net.texi b/docs/system/net.texi
new file mode 100644
index 0000000000..4a6fb2e6a8
--- /dev/null
+++ b/docs/system/net.texi
@@ -0,0 +1,96 @@
+@node pcsys_network
+@section Network emulation
+
+QEMU can simulate several network cards (e.g. PCI or ISA cards on the PC
+target) and can connect them to a network backend on the host or an emulated
+hub. The various host network backends can either be used to connect the NIC of
+the guest to a real network (e.g. by using a TAP devices or the non-privileged
+user mode network stack), or to other guest instances running in another QEMU
+process (e.g. by using the socket host network backend).
+
+@subsection Using TAP network interfaces
+
+This is the standard way to connect QEMU to a real network. QEMU adds
+a virtual network device on your host (called @code{tapN}), and you
+can then configure it as if it was a real ethernet card.
+
+@subsubsection Linux host
+
+As an example, you can download the @file{linux-test-xxx.tar.gz}
+archive and copy the script @file{qemu-ifup} in @file{/etc} and
+configure properly @code{sudo} so that the command @code{ifconfig}
+contained in @file{qemu-ifup} can be executed as root. You must verify
+that your host kernel supports the TAP network interfaces: the
+device @file{/dev/net/tun} must be present.
+
+See @ref{sec_invocation} to have examples of command lines using the
+TAP network interfaces.
+
+@subsubsection Windows host
+
+There is a virtual ethernet driver for Windows 2000/XP systems, called
+TAP-Win32. But it is not included in standard QEMU for Windows,
+so you will need to get it separately. It is part of OpenVPN package,
+so download OpenVPN from : @url{https://openvpn.net/}.
+
+@subsection Using the user mode network stack
+
+By using the option @option{-net user} (default configuration if no
+@option{-net} option is specified), QEMU uses a completely user mode
+network stack (you don't need root privilege to use the virtual
+network). The virtual network configuration is the following:
+
+@example
+
+     guest (10.0.2.15)  <------>  Firewall/DHCP server <-----> Internet
+                           |          (10.0.2.2)
+                           |
+                           ---->  DNS server (10.0.2.3)
+                           |
+                           ---->  SMB server (10.0.2.4)
+@end example
+
+The QEMU VM behaves as if it was behind a firewall which blocks all
+incoming connections. You can use a DHCP client to automatically
+configure the network in the QEMU VM. The DHCP server assign addresses
+to the hosts starting from 10.0.2.15.
+
+In order to check that the user mode network is working, you can ping
+the address 10.0.2.2 and verify that you got an address in the range
+10.0.2.x from the QEMU virtual DHCP server.
+
+Note that ICMP traffic in general does not work with user mode networking.
+@code{ping}, aka. ICMP echo, to the local router (10.0.2.2) shall work,
+however. If you're using QEMU on Linux >= 3.0, it can use unprivileged ICMP
+ping sockets to allow @code{ping} to the Internet. The host admin has to set
+the ping_group_range in order to grant access to those sockets. To allow ping
+for GID 100 (usually users group):
+
+@example
+echo 100 100 > /proc/sys/net/ipv4/ping_group_range
+@end example
+
+When using the built-in TFTP server, the router is also the TFTP
+server.
+
+When using the @option{'-netdev user,hostfwd=...'} option, TCP or UDP
+connections can be redirected from the host to the guest. It allows for
+example to redirect X11, telnet or SSH connections.
+
+@subsection Hubs
+
+QEMU can simulate several hubs. A hub can be thought of as a virtual connection
+between several network devices. These devices can be for example QEMU virtual
+ethernet cards or virtual Host ethernet devices (TAP devices). You can connect
+guest NICs or host network backends to such a hub using the @option{-netdev
+hubport} or @option{-nic hubport} options. The legacy @option{-net} option
+also connects the given device to the emulated hub with ID 0 (i.e. the default
+hub) unless you specify a netdev with @option{-net nic,netdev=xxx} here.
+
+@subsection Connecting emulated networks between QEMU instances
+
+Using the @option{-netdev socket} (or @option{-nic socket} or
+@option{-net socket}) option, it is possible to create emulated
+networks that span several QEMU instances.
+See the description of the @option{-netdev socket} option in the
+@ref{sec_invocation,,Invocation chapter} to have a basic example.
diff --git a/docs/system/quickstart.texi b/docs/system/quickstart.texi
new file mode 100644
index 0000000000..8cd5b4bc6e
--- /dev/null
+++ b/docs/system/quickstart.texi
@@ -0,0 +1,13 @@
+@node pcsys_quickstart
+@section Quick Start
+@cindex quick start
+
+Download and uncompress a hard disk image with Linux installed (e.g.
+@file{linux.img}) and type:
+
+@example
+@value{qemu_system} linux.img
+@end example
+
+Linux should boot and give you a prompt.
+
diff --git a/docs/system/tls.texi b/docs/system/tls.texi
new file mode 100644
index 0000000000..c233531d3a
--- /dev/null
+++ b/docs/system/tls.texi
@@ -0,0 +1,329 @@
+@node network_tls
+@section TLS setup for network services
+
+Almost all network services in QEMU have the ability to use TLS for
+session data encryption, along with x509 certificates for simple
+client authentication. What follows is a description of how to
+generate certificates suitable for usage with QEMU, and applies to
+the VNC server, character devices with the TCP backend, NBD server
+and client, and migration server and client.
+
+At a high level, QEMU requires certificates and private keys to be
+provided in PEM format. Aside from the core fields, the certificates
+should include various extension data sets, including v3 basic
+constraints data, key purpose, key usage and subject alt name.
+
+The GnuTLS package includes a command called @code{certtool} which can
+be used to easily generate certificates and keys in the required format
+with expected data present. Alternatively a certificate management
+service may be used.
+
+At a minimum it is necessary to setup a certificate authority, and
+issue certificates to each server. If using x509 certificates for
+authentication, then each client will also need to be issued a
+certificate.
+
+Assuming that the QEMU network services will only ever be exposed to
+clients on a private intranet, there is no need to use a commercial
+certificate authority to create certificates. A self-signed CA is
+sufficient, and in fact likely to be more secure since it removes
+the ability of malicious 3rd parties to trick the CA into mis-issuing
+certs for impersonating your services. The only likely exception
+where a commercial CA might be desirable is if enabling the VNC
+websockets server and exposing it directly to remote browser clients.
+In such a case it might be useful to use a commercial CA to avoid
+needing to install custom CA certs in the web browsers.
+
+The recommendation is for the server to keep its certificates in either
+@code{/etc/pki/qemu} or for unprivileged users in @code{$HOME/.pki/qemu}.
+
+@menu
+* tls_generate_ca::
+* tls_generate_server::
+* tls_generate_client::
+* tls_creds_setup::
+* tls_psk::
+@end menu
+@node tls_generate_ca
+@subsection Setup the Certificate Authority
+
+This step only needs to be performed once per organization / organizational
+unit. First the CA needs a private key. This key must be kept VERY secret
+and secure. If this key is compromised the entire trust chain of the certificates
+issued with it is lost.
+
+@example
+# certtool --generate-privkey > ca-key.pem
+@end example
+
+To generate a self-signed certificate requires one core piece of information,
+the name of the organization. A template file @code{ca.info} should be
+populated with the desired data to avoid having to deal with interactive
+prompts from certtool:
+@example
+# cat > ca.info <<EOF
+cn = Name of your organization
+ca
+cert_signing_key
+EOF
+# certtool --generate-self-signed \
+           --load-privkey ca-key.pem
+           --template ca.info \
+           --outfile ca-cert.pem
+@end example
+
+The @code{ca} keyword in the template sets the v3 basic constraints extension
+to indicate this certificate is for a CA, while @code{cert_signing_key} sets
+the key usage extension to indicate this will be used for signing other keys.
+The generated @code{ca-cert.pem} file should be copied to all servers and
+clients wishing to utilize TLS support in the VNC server. The @code{ca-key.pem}
+must not be disclosed/copied anywhere except the host responsible for issuing
+certificates.
+
+@node tls_generate_server
+@subsection Issuing server certificates
+
+Each server (or host) needs to be issued with a key and certificate. When connecting
+the certificate is sent to the client which validates it against the CA certificate.
+The core pieces of information for a server certificate are the hostnames and/or IP
+addresses that will be used by clients when connecting. The hostname / IP address
+that the client specifies when connecting will be validated against the hostname(s)
+and IP address(es) recorded in the server certificate, and if no match is found
+the client will close the connection.
+
+Thus it is recommended that the server certificate include both the fully qualified
+and unqualified hostnames. If the server will have permanently assigned IP address(es),
+and clients are likely to use them when connecting, they may also be included in the
+certificate. Both IPv4 and IPv6 addresses are supported. Historically certificates
+only included 1 hostname in the @code{CN} field, however, usage of this field for
+validation is now deprecated. Instead modern TLS clients will validate against the
+Subject Alt Name extension data, which allows for multiple entries. In the future
+usage of the @code{CN} field may be discontinued entirely, so providing SAN
+extension data is strongly recommended.
+
+On the host holding the CA, create template files containing the information
+for each server, and use it to issue server certificates.
+
+@example
+# cat > server-hostNNN.info <<EOF
+organization = Name  of your organization
+cn = hostNNN.foo.example.com
+dns_name = hostNNN
+dns_name = hostNNN.foo.example.com
+ip_address = 10.0.1.87
+ip_address = 192.8.0.92
+ip_address = 2620:0:cafe::87
+ip_address = 2001:24::92
+tls_www_server
+encryption_key
+signing_key
+EOF
+# certtool --generate-privkey > server-hostNNN-key.pem
+# certtool --generate-certificate \
+           --load-ca-certificate ca-cert.pem \
+           --load-ca-privkey ca-key.pem \
+           --load-privkey server-hostNNN-key.pem \
+           --template server-hostNNN.info \
+           --outfile server-hostNNN-cert.pem
+@end example
+
+The @code{dns_name} and @code{ip_address} fields in the template are setting
+the subject alt name extension data. The @code{tls_www_server} keyword is the
+key purpose extension to indicate this certificate is intended for usage in
+a web server. Although QEMU network services are not in fact HTTP servers
+(except for VNC websockets), setting this key purpose is still recommended.
+The @code{encryption_key} and @code{signing_key} keyword is the key usage
+extension to indicate this certificate is intended for usage in the data
+session.
+
+The @code{server-hostNNN-key.pem} and @code{server-hostNNN-cert.pem} files
+should now be securely copied to the server for which they were generated,
+and renamed to @code{server-key.pem} and @code{server-cert.pem} when added
+to the @code{/etc/pki/qemu} directory on the target host. The @code{server-key.pem}
+file is security sensitive and should be kept protected with file mode 0600
+to prevent disclosure.
+
+@node tls_generate_client
+@subsection Issuing client certificates
+
+The QEMU x509 TLS credential setup defaults to enabling client verification
+using certificates, providing a simple authentication mechanism. If this
+default is used, each client also needs to be issued a certificate. The client
+certificate contains enough metadata to uniquely identify the client with the
+scope of the certificate authority. The client certificate would typically
+include fields for organization, state, city, building, etc.
+
+Once again on the host holding the CA, create template files containing the
+information for each client, and use it to issue client certificates.
+
+
+@example
+# cat > client-hostNNN.info <<EOF
+country = GB
+state = London
+locality = City Of London
+organization = Name of your organization
+cn = hostNNN.foo.example.com
+tls_www_client
+encryption_key
+signing_key
+EOF
+# certtool --generate-privkey > client-hostNNN-key.pem
+# certtool --generate-certificate \
+           --load-ca-certificate ca-cert.pem \
+           --load-ca-privkey ca-key.pem \
+           --load-privkey client-hostNNN-key.pem \
+           --template client-hostNNN.info \
+           --outfile client-hostNNN-cert.pem
+@end example
+
+The subject alt name extension data is not required for clients, so the
+the @code{dns_name} and @code{ip_address} fields are not included.
+The @code{tls_www_client} keyword is the key purpose extension to indicate
+this certificate is intended for usage in a web client. Although QEMU
+network clients are not in fact HTTP clients, setting this key purpose is
+still recommended. The @code{encryption_key} and @code{signing_key} keyword
+is the key usage extension to indicate this certificate is intended for
+usage in the data session.
+
+The @code{client-hostNNN-key.pem} and @code{client-hostNNN-cert.pem} files
+should now be securely copied to the client for which they were generated,
+and renamed to @code{client-key.pem} and @code{client-cert.pem} when added
+to the @code{/etc/pki/qemu} directory on the target host. The @code{client-key.pem}
+file is security sensitive and should be kept protected with file mode 0600
+to prevent disclosure.
+
+If a single host is going to be using TLS in both a client and server
+role, it is possible to create a single certificate to cover both roles.
+This would be quite common for the migration and NBD services, where a
+QEMU process will be started by accepting a TLS protected incoming migration,
+and later itself be migrated out to another host. To generate a single
+certificate, simply include the template data from both the client and server
+instructions in one.
+
+@example
+# cat > both-hostNNN.info <<EOF
+country = GB
+state = London
+locality = City Of London
+organization = Name of your organization
+cn = hostNNN.foo.example.com
+dns_name = hostNNN
+dns_name = hostNNN.foo.example.com
+ip_address = 10.0.1.87
+ip_address = 192.8.0.92
+ip_address = 2620:0:cafe::87
+ip_address = 2001:24::92
+tls_www_server
+tls_www_client
+encryption_key
+signing_key
+EOF
+# certtool --generate-privkey > both-hostNNN-key.pem
+# certtool --generate-certificate \
+           --load-ca-certificate ca-cert.pem \
+           --load-ca-privkey ca-key.pem \
+           --load-privkey both-hostNNN-key.pem \
+           --template both-hostNNN.info \
+           --outfile both-hostNNN-cert.pem
+@end example
+
+When copying the PEM files to the target host, save them twice,
+once as @code{server-cert.pem} and @code{server-key.pem}, and
+again as @code{client-cert.pem} and @code{client-key.pem}.
+
+@node tls_creds_setup
+@subsection TLS x509 credential configuration
+
+QEMU has a standard mechanism for loading x509 credentials that will be
+used for network services and clients. It requires specifying the
+@code{tls-creds-x509} class name to the @code{--object} command line
+argument for the system emulators.  Each set of credentials loaded should
+be given a unique string identifier via the @code{id} parameter. A single
+set of TLS credentials can be used for multiple network backends, so VNC,
+migration, NBD, character devices can all share the same credentials. Note,
+however, that credentials for use in a client endpoint must be loaded
+separately from those used in a server endpoint.
+
+When specifying the object, the @code{dir} parameters specifies which
+directory contains the credential files. This directory is expected to
+contain files with the names mentioned previously, @code{ca-cert.pem},
+@code{server-key.pem}, @code{server-cert.pem}, @code{client-key.pem}
+and @code{client-cert.pem} as appropriate. It is also possible to
+include a set of pre-generated Diffie-Hellman (DH) parameters in a file
+@code{dh-params.pem}, which can be created using the
+@code{certtool --generate-dh-params} command. If omitted, QEMU will
+dynamically generate DH parameters when loading the credentials.
+
+The @code{endpoint} parameter indicates whether the credentials will
+be used for a network client or server, and determines which PEM
+files are loaded.
+
+The @code{verify} parameter determines whether x509 certificate
+validation should be performed. This defaults to enabled, meaning
+clients will always validate the server hostname against the
+certificate subject alt name fields and/or CN field. It also
+means that servers will request that clients provide a certificate
+and validate them. Verification should never be turned off for
+client endpoints, however, it may be turned off for server endpoints
+if an alternative mechanism is used to authenticate clients. For
+example, the VNC server can use SASL to authenticate clients
+instead.
+
+To load server credentials with client certificate validation
+enabled
+
+@example
+@value{qemu_system} -object tls-creds-x509,id=tls0,dir=/etc/pki/qemu,endpoint=server
+@end example
+
+while to load client credentials use
+
+@example
+@value{qemu_system} -object tls-creds-x509,id=tls0,dir=/etc/pki/qemu,endpoint=client
+@end example
+
+Network services which support TLS will all have a @code{tls-creds}
+parameter which expects the ID of the TLS credentials object. For
+example with VNC:
+
+@example
+@value{qemu_system} -vnc 0.0.0.0:0,tls-creds=tls0
+@end example
+
+@node tls_psk
+@subsection TLS Pre-Shared Keys (PSK)
+
+Instead of using certificates, you may also use TLS Pre-Shared Keys
+(TLS-PSK).  This can be simpler to set up than certificates but is
+less scalable.
+
+Use the GnuTLS @code{psktool} program to generate a @code{keys.psk}
+file containing one or more usernames and random keys:
+
+@example
+mkdir -m 0700 /tmp/keys
+psktool -u rich -p /tmp/keys/keys.psk
+@end example
+
+TLS-enabled servers such as qemu-nbd can use this directory like so:
+
+@example
+qemu-nbd \
+  -t -x / \
+  --object tls-creds-psk,id=tls0,endpoint=server,dir=/tmp/keys \
+  --tls-creds tls0 \
+  image.qcow2
+@end example
+
+When connecting from a qemu-based client you must specify the
+directory containing @code{keys.psk} and an optional @var{username}
+(defaults to ``qemu''):
+
+@example
+qemu-img info \
+  --object tls-creds-psk,id=tls0,dir=/tmp/keys,username=rich,endpoint=client \
+  --image-opts \
+  file.driver=nbd,file.host=localhost,file.port=10809,file.tls-creds=tls0,file.export=/
+@end example
+
diff --git a/docs/system/usb.texi b/docs/system/usb.texi
new file mode 100644
index 0000000000..840adac978
--- /dev/null
+++ b/docs/system/usb.texi
@@ -0,0 +1,115 @@
+@node pcsys_usb
+@section USB emulation
+
+QEMU can emulate a PCI UHCI, OHCI, EHCI or XHCI USB controller. You can
+plug virtual USB devices or real host USB devices (only works with certain
+host operating systems). QEMU will automatically create and connect virtual
+USB hubs as necessary to connect multiple USB devices.
+
+@menu
+* usb_devices::
+* host_usb_devices::
+@end menu
+@node usb_devices
+@subsection Connecting USB devices
+
+USB devices can be connected with the @option{-device usb-...} command line
+option or the @code{device_add} monitor command. Available devices are:
+
+@table @code
+@item usb-mouse
+Virtual Mouse.  This will override the PS/2 mouse emulation when activated.
+@item usb-tablet
+Pointer device that uses absolute coordinates (like a touchscreen).
+This means QEMU is able to report the mouse position without having
+to grab the mouse.  Also overrides the PS/2 mouse emulation when activated.
+@item usb-storage,drive=@var{drive_id}
+Mass storage device backed by @var{drive_id} (@pxref{disk_images})
+@item usb-uas
+USB attached SCSI device, see
+@url{https://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/usb-storage.txt,usb-storage.txt}
+for details
+@item usb-bot
+Bulk-only transport storage device, see
+@url{https://git.qemu.org/?p=qemu.git;a=blob_plain;f=docs/usb-storage.txt,usb-storage.txt}
+for details here, too
+@item usb-mtp,rootdir=@var{dir}
+Media transfer protocol device, using @var{dir} as root of the file tree
+that is presented to the guest.
+@item usb-host,hostbus=@var{bus},hostaddr=@var{addr}
+Pass through the host device identified by @var{bus} and @var{addr}
+@item usb-host,vendorid=@var{vendor},productid=@var{product}
+Pass through the host device identified by @var{vendor} and @var{product} ID
+@item usb-wacom-tablet
+Virtual Wacom PenPartner tablet.  This device is similar to the @code{tablet}
+above but it can be used with the tslib library because in addition to touch
+coordinates it reports touch pressure.
+@item usb-kbd
+Standard USB keyboard.  Will override the PS/2 keyboard (if present).
+@item usb-serial,chardev=@var{id}
+Serial converter. This emulates an FTDI FT232BM chip connected to host character
+device @var{id}.
+@item usb-braille,chardev=@var{id}
+Braille device.  This will use BrlAPI to display the braille output on a real
+or fake device referenced by @var{id}.
+@item usb-net[,netdev=@var{id}]
+Network adapter that supports CDC ethernet and RNDIS protocols.  @var{id}
+specifies a netdev defined with @code{-netdev @dots{},id=@var{id}}.
+For instance, user-mode networking can be used with
+@example
+@value{qemu_system} [...] -netdev user,id=net0 -device usb-net,netdev=net0
+@end example
+@item usb-ccid
+Smartcard reader device
+@item usb-audio
+USB audio device
+@end table
+
+@node host_usb_devices
+@subsection Using host USB devices on a Linux host
+
+WARNING: this is an experimental feature. QEMU will slow down when
+using it. USB devices requiring real time streaming (i.e. USB Video
+Cameras) are not supported yet.
+
+@enumerate
+@item If you use an early Linux 2.4 kernel, verify that no Linux driver
+is actually using the USB device. A simple way to do that is simply to
+disable the corresponding kernel module by renaming it from @file{mydriver.o}
+to @file{mydriver.o.disabled}.
+
+@item Verify that @file{/proc/bus/usb} is working (most Linux distributions should enable it by default). You should see something like that:
+@example
+ls /proc/bus/usb
+001  devices  drivers
+@end example
+
+@item Since only root can access to the USB devices directly, you can either launch QEMU as root or change the permissions of the USB devices you want to use. For testing, the following suffices:
+@example
+chown -R myuid /proc/bus/usb
+@end example
+
+@item Launch QEMU and do in the monitor:
+@example
+info usbhost
+  Device 1.2, speed 480 Mb/s
+    Class 00: USB device 1234:5678, USB DISK
+@end example
+You should see the list of the devices you can use (Never try to use
+hubs, it won't work).
+
+@item Add the device in QEMU by using:
+@example
+device_add usb-host,vendorid=0x1234,productid=0x5678
+@end example
+
+Normally the guest OS should report that a new USB device is plugged.
+You can use the option @option{-device usb-host,...} to do the same.
+
+@item Now you can try to use the host USB device in QEMU.
+
+@end enumerate
+
+When relaunching QEMU, you may have to unplug and plug again the USB
+device to make it work again (this is a bug).
+
diff --git a/docs/system/vnc-security.texi b/docs/system/vnc-security.texi
new file mode 100644
index 0000000000..abf7f7fa43
--- /dev/null
+++ b/docs/system/vnc-security.texi
@@ -0,0 +1,196 @@
+@node vnc_security
+@section VNC security
+
+The VNC server capability provides access to the graphical console
+of the guest VM across the network. This has a number of security
+considerations depending on the deployment scenarios.
+
+@menu
+* vnc_sec_none::
+* vnc_sec_password::
+* vnc_sec_certificate::
+* vnc_sec_certificate_verify::
+* vnc_sec_certificate_pw::
+* vnc_sec_sasl::
+* vnc_sec_certificate_sasl::
+* vnc_setup_sasl::
+@end menu
+@node vnc_sec_none
+@subsection Without passwords
+
+The simplest VNC server setup does not include any form of authentication.
+For this setup it is recommended to restrict it to listen on a UNIX domain
+socket only. For example
+
+@example
+@value{qemu_system} [...OPTIONS...] -vnc unix:/home/joebloggs/.qemu-myvm-vnc
+@end example
+
+This ensures that only users on local box with read/write access to that
+path can access the VNC server. To securely access the VNC server from a
+remote machine, a combination of netcat+ssh can be used to provide a secure
+tunnel.
+
+@node vnc_sec_password
+@subsection With passwords
+
+The VNC protocol has limited support for password based authentication. Since
+the protocol limits passwords to 8 characters it should not be considered
+to provide high security. The password can be fairly easily brute-forced by
+a client making repeat connections. For this reason, a VNC server using password
+authentication should be restricted to only listen on the loopback interface
+or UNIX domain sockets. Password authentication is not supported when operating
+in FIPS 140-2 compliance mode as it requires the use of the DES cipher. Password
+authentication is requested with the @code{password} option, and then once QEMU
+is running the password is set with the monitor. Until the monitor is used to
+set the password all clients will be rejected.
+
+@example
+@value{qemu_system} [...OPTIONS...] -vnc :1,password -monitor stdio
+(qemu) change vnc password
+Password: ********
+(qemu)
+@end example
+
+@node vnc_sec_certificate
+@subsection With x509 certificates
+
+The QEMU VNC server also implements the VeNCrypt extension allowing use of
+TLS for encryption of the session, and x509 certificates for authentication.
+The use of x509 certificates is strongly recommended, because TLS on its
+own is susceptible to man-in-the-middle attacks. Basic x509 certificate
+support provides a secure session, but no authentication. This allows any
+client to connect, and provides an encrypted session.
+
+@example
+@value{qemu_system} [...OPTIONS...] \
+  -object tls-creds-x509,id=tls0,dir=/etc/pki/qemu,endpoint=server,verify-peer=no \
+  -vnc :1,tls-creds=tls0 -monitor stdio
+@end example
+
+In the above example @code{/etc/pki/qemu} should contain at least three files,
+@code{ca-cert.pem}, @code{server-cert.pem} and @code{server-key.pem}. Unprivileged
+users will want to use a private directory, for example @code{$HOME/.pki/qemu}.
+NB the @code{server-key.pem} file should be protected with file mode 0600 to
+only be readable by the user owning it.
+
+@node vnc_sec_certificate_verify
+@subsection With x509 certificates and client verification
+
+Certificates can also provide a means to authenticate the client connecting.
+The server will request that the client provide a certificate, which it will
+then validate against the CA certificate. This is a good choice if deploying
+in an environment with a private internal certificate authority. It uses the
+same syntax as previously, but with @code{verify-peer} set to @code{yes}
+instead.
+
+@example
+@value{qemu_system} [...OPTIONS...] \
+  -object tls-creds-x509,id=tls0,dir=/etc/pki/qemu,endpoint=server,verify-peer=yes \
+  -vnc :1,tls-creds=tls0 -monitor stdio
+@end example
+
+
+@node vnc_sec_certificate_pw
+@subsection With x509 certificates, client verification and passwords
+
+Finally, the previous method can be combined with VNC password authentication
+to provide two layers of authentication for clients.
+
+@example
+@value{qemu_system} [...OPTIONS...] \
+  -object tls-creds-x509,id=tls0,dir=/etc/pki/qemu,endpoint=server,verify-peer=yes \
+  -vnc :1,tls-creds=tls0,password -monitor stdio
+(qemu) change vnc password
+Password: ********
+(qemu)
+@end example
+
+
+@node vnc_sec_sasl
+@subsection With SASL authentication
+
+The SASL authentication method is a VNC extension, that provides an
+easily extendable, pluggable authentication method. This allows for
+integration with a wide range of authentication mechanisms, such as
+PAM, GSSAPI/Kerberos, LDAP, SQL databases, one-time keys and more.
+The strength of the authentication depends on the exact mechanism
+configured. If the chosen mechanism also provides a SSF layer, then
+it will encrypt the datastream as well.
+
+Refer to the later docs on how to choose the exact SASL mechanism
+used for authentication, but assuming use of one supporting SSF,
+then QEMU can be launched with:
+
+@example
+@value{qemu_system} [...OPTIONS...] -vnc :1,sasl -monitor stdio
+@end example
+
+@node vnc_sec_certificate_sasl
+@subsection With x509 certificates and SASL authentication
+
+If the desired SASL authentication mechanism does not supported
+SSF layers, then it is strongly advised to run it in combination
+with TLS and x509 certificates. This provides securely encrypted
+data stream, avoiding risk of compromising of the security
+credentials. This can be enabled, by combining the 'sasl' option
+with the aforementioned TLS + x509 options:
+
+@example
+@value{qemu_system} [...OPTIONS...] \
+  -object tls-creds-x509,id=tls0,dir=/etc/pki/qemu,endpoint=server,verify-peer=yes \
+  -vnc :1,tls-creds=tls0,sasl -monitor stdio
+@end example
+
+@node vnc_setup_sasl
+
+@subsection Configuring SASL mechanisms
+
+The following documentation assumes use of the Cyrus SASL implementation on a
+Linux host, but the principles should apply to any other SASL implementation
+or host. When SASL is enabled, the mechanism configuration will be loaded from
+system default SASL service config /etc/sasl2/qemu.conf. If running QEMU as an
+unprivileged user, an environment variable SASL_CONF_PATH can be used to make
+it search alternate locations for the service config file.
+
+If the TLS option is enabled for VNC, then it will provide session encryption,
+otherwise the SASL mechanism will have to provide encryption. In the latter
+case the list of possible plugins that can be used is drastically reduced. In
+fact only the GSSAPI SASL mechanism provides an acceptable level of security
+by modern standards. Previous versions of QEMU referred to the DIGEST-MD5
+mechanism, however, it has multiple serious flaws described in detail in
+RFC 6331 and thus should never be used any more. The SCRAM-SHA-1 mechanism
+provides a simple username/password auth facility similar to DIGEST-MD5, but
+does not support session encryption, so can only be used in combination with
+TLS.
+
+When not using TLS the recommended configuration is
+
+@example
+mech_list: gssapi
+keytab: /etc/qemu/krb5.tab
+@end example
+
+This says to use the 'GSSAPI' mechanism with the Kerberos v5 protocol, with
+the server principal stored in /etc/qemu/krb5.tab. For this to work the
+administrator of your KDC must generate a Kerberos principal for the server,
+with a name of 'qemu/somehost.example.com@@EXAMPLE.COM' replacing
+'somehost.example.com' with the fully qualified host name of the machine
+running QEMU, and 'EXAMPLE.COM' with the Kerberos Realm.
+
+When using TLS, if username+password authentication is desired, then a
+reasonable configuration is
+
+@example
+mech_list: scram-sha-1
+sasldb_path: /etc/qemu/passwd.db
+@end example
+
+The @code{saslpasswd2} program can be used to populate the @code{passwd.db}
+file with accounts.
+
+Other SASL configurations will be left as an exercise for the reader. Note that
+all mechanisms, except GSSAPI, should be combined with use of TLS to ensure a
+secure data channel.
+
+