The guest CPU definition has always been updated automatically during
migration. And currently we just transform any host-model CPU into a
custom one when a domain starts.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Add a new attribute 'rendernode' to <gl> spice element.
Give it to QEMU if qemu supports it (queued for 2.9).
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This part introduces new xml elements for file based
memorybacking support and their parsing.
(It allows vhost-user to be used without hugepages.)
New xml elements:
<memoryBacking>
<source type="file|anonymous"/>
<access mode="shared|private"/>
<allocation mode="immediate|ondemand"/>
</memoryBacking>
So far we allow to set MTU for libvirt networks. However, not all
domain interfaces have to be plugged into a libvirt network and
even if they are, they might want to have a different MTU (e.g.
for testing purposes).
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This element has been introduced in fe053dbea7, but isn't
documented yet. After exactly 6 years I guess we can finally
document it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This patch adds support and documentation for
a generalized hardware cache event called cache_l1d
perf event.
Signed-off-by: Nitesh Konkar <nitkon12@linux.vnet.ibm.com>
Documents in formatdomain.html that when migrating a guest
defined with the host-passthrough CPU model from a machine that
is running on a newer CPU model than the destination machine's
CPU model, it is very likely that the guest will crash upon
arrival.
Signed-off-by: Jason J. Herne <jjherne@linux.vnet.ibm.com>
With current perf framework, this patch adds support and documentation
for the branch_instructions perf event.
Signed-off-by: Nitesh Konkar <nitkon12@linux.vnet.ibm.com>
Modify _virDomainBlockIoTuneInfo and rng schema to support the group_name
option for iotune throttling. Document the new value.
Signed-off-by: John Ferlan <jferlan@redhat.com>
With the QEMU components in place, provide the XML parsing to
invoke that code when given the following XML snippet:
<hostdev mode='subsystem' type='scsi_host'>
<source protocol='vhost' wwpn='naa.501234567890abcd'/>
</hostdev>
An optional address element can be specified within the hostdev
(pick CCW or PCI as necessary):
<address type='ccw' cssid='0xfe' ssid='0x0' devno='0x0625'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
Add basic vhost-scsi tests which were cloned from hostdev-scsi-virtio-scsi
in both xml2argv and xml2xml. Added ones for both vhost-scsi-ccw and
vhost-scsi-pci since the syntaxes are slightly different between them.
Also adjusted the docs to describe the changes.
Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Reviewed-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
The <pre/> section is rendered as-is on the page. That is, if all
the lines are prefixed with 4 spaces the rendered page will also
have them. Problem is if we put a box around such <pre/> because
the content might not fix into it.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
The old ivshmem is deprecated in QEMU, so let's use the better
ivshmem-{plain,doorbell} variants instead.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
Add an optional "tls='yes|no'" attribute for a TCP chardev.
For QEMU, this will allow for disabling the host config setting of the
'chardev_tls' for a domain chardev channel by setting the value to "no" or
to attempt to use a host TLS environment when setting the value to "yes"
when the host config 'chardev_tls' setting is disabled, but a TLS environment
is configured via either the host config 'chardev_tls_x509_cert_dir' or
'default_tls_x509_cert_dir'
Signed-off-by: John Ferlan <jferlan@redhat.com>
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Certain operations may make the vcpu order information invalid. Since
the order is primarily used to ensure migration compatibility and has
basically no other user benefits, clear the order prior to certain
operations and document that it may be cleared.
All the operations that would clear the order can still be properly
executed by defining a new domain configuration rather than using the
helper APIs.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1370357
When support was added for the kvm hidden='on' attribute in commit
d07116, the version requirement was listed as "2.1.0 (QEMU
only)". However, this was added when libvirt was at version 1.2.8 - it
is *QEMU* that must be at version 2.1.0 or later.
This went unnoticed for a very long time (over 2 years). Then a week
or two ago a new Windows convert in the #virt channel on OFTC was told
he needed to use this feature (to prevent nvidia drivers in a guest
from refusing to work due to being run in a virtual machine). There
was some problem with it being recognized and "someone" (it may have
been me, or may have been someone else, I don't remember) pointed out
that the documentation at
http://www.libvirt.org/formatdomain.html
says that it requires libvirt 2.1.0. The next several days were filled
with agony as a new convert to Linux first tried to upgrade a Linux
Mint host running their "LTS" version to something newer, then tried
to install a libvirt build built for Ubuntu onto this, and later back
to the old LTS Linux Mint. After this he tried building his own
libvirt from source (with all the expected problems), and finally
switched to Fedora. In the end it was hours and hours of everybody's
lives that they will never get back. To now learn that he didn't need
to do this (his original libvirt version was 1.3.3, so whatever his
problem was, it was elsewhere) makes the pain all that much worse.
To prevent this from happening again, this simple patch changes the
version requirement for the kvm hidden attribute from "2.1.0 (QEMU
only)" to "1.2.8 (QEMU 2.1.0)".
So far only guestfwd and virtio were supported. Add an additional
for Xen as libxl channels create a Xen console visible to the guest.
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
With current perf framework, this patch adds support and documentation
for more perf events, including cache misses, cache references, cpu cycles,
and instructions.
Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.com>
Add support for using the new approach to hotplug vcpus using device_add
during startup of qemu to allow sparse vcpu topologies.
There are a few limitations imposed by qemu on the supported
configuration:
- vcpu0 needs to be always present and not hotpluggable
- non-hotpluggable cpus need to be ordered at the beginning
- order of the vcpus needs to be unique for every single hotpluggable
entity
Qemu also doesn't really allow to query the information necessary to
start a VM with the vcpus directly on the commandline. Fortunately they
can be hotplugged during startup.
The new hotplug code uses the following approach:
- non-hotpluggable vcpus are counted and put to the -smp option
- qemu is started
- qemu is queried for the necessary information
- the configuration is checked
- the hotpluggable vcpus are hotplugged
- vcpus are started
This patch adds a lot of checking code and enables the support to
specify the individual vcpu element with qemu.
Individual vCPU hotplug requires us to track the state of any vCPU. To
allow this add the following XML:
<domain>
...
<vcpu current='2'>3</vcpu>
<vcpus>
<vcpu id='0' enabled='yes' hotpluggable='no' order='1'/>
<vcpu id='1' enabled='yes' hotpluggable='yes' order='2'/>
<vcpu id='1' enabled='no' hotpluggable='yes'/>
</vcpus>
...
The 'enabled' attribute allows to control the state of the vcpu.
'hotpluggable' controls whether given vcpu can be hotplugged and 'order'
allows to specify the order to add the vcpus.
I apparently misunderstood Marcel's description of what could and
couldn't be plugged into qemu's pxb-pcie controller (known as
pcie-expander-bus in libvirt) - I specifically allowed directly
connecting a pcie-switch-upstream-port, and it turns out that causes
the guest kernel to crash.
This patch forbids such a connection, and updates the xml docs
appropriately.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1361172
This element will control secure boot implemented by some
firmwares. If the firmware used in <loader/> does support the
feature we must tell it to the underlying hypervisor. However, we
can't know whether loader does support it or not just by looking
at the file. Therefore we have to have an attribute to the
element where users can tell us whether the firmware is secure
boot enabled or not.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Since its release of 2.4.0 qemu is able to enable System
Management Module in the firmware, or disable it. We should
expose this capability in the XML. Unfortunately, there's no good
way to determine whether the binary we are talking to supports
it. I mean, if qemu's run with real machine type, the smm
attribute can be seen in 'qom-list /machine' output. But it's not
there when qemu's run with -M none. Therefore we're stuck with
version based check.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
https://bugzilla.redhat.com/show_bug.cgi?id=1356937
Add the definitions to allow for viewing/setting cgroup period and quota
limits for IOThreads.
This is similar to the work done for emulator quota and period by
commit ids 'b65dafa' and 'e051c482'.
Being able to view/set the IOThread specific values is related to more
recent changes adding global period (commmit id '4d92d58f') and global
quota (commit id '55ecdae') definitions and qemu support (commit id
'4e17ff79' and 'fbcbd1b2'). With a global setting though, if somehow
the IOThread value in the cgroup hierarchy was set "outside of libvirt"
to a value that is incompatible with the global value.
Allowing control over IOThread specific values provides the capability
to alter the IOThread values as necessary.
According to libxl implementation, it supports pvusb
controller of version 1.1 and version 2.0, and it
supports two types of backend, 'pvusb' (dom0 backend)
and 'qusb' (qemu backend). But currently pvusb backend
is not checked in yet.
To match libxl support, extend usb controller schema
to support two more models: qusb1 (qusb, version 1.1)
and 'qusb2' (qusb version 2.0).
Signed-off-by: Chunyan Liu <cyliu@suse.com>
To allow using failover with gluster it's necessary to specify multiple
volume hosts. Add support for starting qemu with such configurations.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
This is place as a sub-element of <source>, where other aspects of the
host-side connection to the network device are located (network or
bridge name, udp listen port, etc). It's a bit odd that the interface
we're configuring with this info is itself named in <target dev='x'/>,
but that ship sailed long ago:
<interface type='ethernet'>
<mac address='00:16:3e:0f:ef:8a'/>
<source>
<ip address='192.168.122.12' family='ipv4'
prefix='24' peer='192.168.122.1'/>
<ip address='192.168.122.13' family='ipv4' prefix='24'/>
<route family='ipv4' address='0.0.0.0'
gateway='192.168.122.1'/>
<route family='ipv4' address='192.168.124.0' prefix='24'
gateway='192.168.124.1'/>
</source>
</interface>
In practice, this will likely only be useful for type='ethernet', so
its presence in any other type of interface is currently forbidden in
the generic device Validate function (but it's been put into the
general population of virDomainNetDef rather than the
ethernet-specific union member so that 1) we can more easily add the
capability to other types if needed, and 2) we can retain the info
when set to an invalid interface type all the way through to
validation and report a proper error, rather than just ignoring it
(which is currently what happens for many other type-specific
settings).
(NB: The already-existing configuration of IP info for the guest-side
of interfaces is in subelements directly under <interface>, and the
name of the guest-side interface (when configurable) is in <guest
dev='x'/>).
(This patch had been pushed earlier in
commit fe6a77898a, but was reverted in
commit d658456530 because it had been
accidentally pushed during the freeze for release 2.0.0)
The peer attribute is used to set the property of the same name in the
interface IP info:
<interface type='ethernet'>
...
<ip family='ipv4' address='192.168.122.5'
prefix='32' peer='192.168.122.6'/>
...
</interface>
Note that this element is used to set the IP information on the
*guest* side interface, not the host side interface - that will be
supported in an upcoming patch.
(This patch now has quite a history: it was originally pushed in
commit 690969af, which was subsequently reverted in commit 1d14b13f,
then reworked and pushed (along with a lot of other related/supporting
patches) in commit 93135abf1; however *that* commit had been
accidentally pushed during dev. freeze for release 2.0.0, so it was
again reverted in commit f6acf039f0).
Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>
Signed-off-by: Laine Stump <laine@laine.org>
This is place as a sub-element of <source>, where other aspects of the
host-side connection to the network device are located (network or
bridge name, udp listen port, etc). It's a bit odd that the interface
we're configuring with this info is itself named in <target dev='x'/>,
but that ship sailed long ago:
<interface type='ethernet'>
<mac address='00:16:3e:0f:ef:8a'/>
<source>
<ip address='192.168.122.12' family='ipv4'
prefix='24' peer='192.168.122.1'/>
<ip address='192.168.122.13' family='ipv4' prefix='24'/>
<route family='ipv4' address='0.0.0.0'
gateway='192.168.122.1'/>
<route family='ipv4' address='192.168.124.0' prefix='24'
gateway='192.168.124.1'/>
</source>
</interface>
In practice, this will likely only be useful for type='ethernet', so
its presence in any other type of interface is currently forbidden in
the generic device Validate function (but it's been put into the
general population of virDomainNetDef rather than the
ethernet-specific union member so that 1) we can more easily add the
capability to other types, and 2) we can retain the info when set to
an invalid interface type all the way through to validation and report
a proper error, rather than just ignoring it (which is currently what
happens for many other type-specific settings).
(NB: The already-existing configuration of IP info for the guest-side
of interfaces is in subelements directly under <interface>, and the
name of the guest-side interface (when configurable) is in <guest
dev='x'/>).
The peer attribute is used to set the property of the same name in the
interface IP info:
<interface type='ethernet'>
...
<ip family='ipv4' address='192.168.122.5'
prefix='32' peer='192.168.122.6'/>
...
</interface>
Note that this element is used to set the IP information on the
*guest* side interface, not the host side interface - that will be
supported in an upcoming patch.
(This is an updated *re*-commit of commit 690969af, which was
subsequently reverted in commit 1d14b13f).
Signed-off-by: Vasiliy Tolstov <v.tolstov@selfip.ru>
Signed-off-by: Laine Stump <laine@laine.org>
In the case of chassisNr (used to set chassis_nr of a pci-bridge
controller), 0 is reserved for / used by the pci[e]-root bus. In the
base of busNr, a value of 0 would mean that the root bus had no places
available to plug in new buses, including the pxb itself (the
documentation I wrote for pxb even noted the limit of busNr as 1.254).
NB: oddly, the "chassis" attribute, which is used for pcie-root-port
and pcie-switch-downstream-port *can* be set to 0, since it's the
combination of {chassis, slot} that needs to be unique, not chassis by
itself (and slot 0 of pcie-root is reserved, while pcie-*-port can use
*only* slot 0).
This resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1342962
There was no documentation at all for the XML part. I added at least
some. The 2.0.0 introduction date is deliberate as the parser for the
XML is broken.
The schema file was missing entries for 'mbml' and 'mbmt'.
This option allows or disallows detection of zero-writes if it is set to
"on" or "off", respectively. It can be also set to "unmap" in which
case it will try discarding that part of image based on the value of the
"discard" option.
Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
This new listen type is currently supported only by spice graphics.
It's introduced to make it easier and clearer specify to not listen
anywhere in order to start a guest with OpenGL support.
The old way to do this was set spice graphics autoport='no' and don't
specify any ports. The new way is to use <listen type='none'/>. In
order to be able to migrate to old libvirt the migratable XML will be
generated without the listen element and with autoport='no'. Also the
old configuration will be automatically converted to the this listen
type.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
VNC graphics already supports sockets but only via 'socket' attribute.
This patch coverts that attribute into listen type 'socket'.
For backward compatibility we need to handle listen type 'socket' and 'socket'
attribute properly to support old XMLs and new XMLs. If both are provided they
have to match, if only one of them is provided we need to be able to parse that
configuration too.
To not break migration back to old libvirt if the socket is provided by user we
need to generate migratable XML without the listen element and use only 'socket'
attribute.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Hand-entering indexes for 20 PCI controllers is not as tedious as
manually determining and entering their PCI addresses, but it's still
annoying, and the algorithm for determining the proper index is
incredibly simple (in all cases except one) - just pick the lowest
unused index.
The one exception is USB2 controllers because multiple controllers in
the same group have the same index. For these we look to see if 1) the
most recently added USB controller is also a USB2 controller, and 2)
the group *that* controller belongs to doesn't yet have a controller
of the exact model we're just now adding - if both are true, the new
controller gets the same index, but in all other cases we just assign
the lowest unused index.
With this patch in place and combined with the automatic PCI address
assignment, we can define a PCIe switch with several ports like this:
<controller type='pci' model='pcie-root-port'/>
<controller type='pci' model='pcie-switch-upstream-port'/>
<controller type='pci' model='pcie-switch-downstream-port'/>
<controller type='pci' model='pcie-switch-downstream-port'/>
<controller type='pci' model='pcie-switch-downstream-port'/>
<controller type='pci' model='pcie-switch-downstream-port'/>
<controller type='pci' model='pcie-switch-downstream-port'/>
...
These will each get a unique index, and PCI addresses that connect
them together appropriately with no pesky numbers required.
Add a new element to <domain> XML:
<os>
<acpi>
<table type="slic">/path/to/acpi/table/file</table>
</acpi>
</os>
To supply a path to a SLIC (Software Licensing) ACPI
table blob.
https://bugzilla.redhat.com/show_bug.cgi?id=1327537
Prior to this, <address type='pci'/> wasn't allowed when parsing
(domain+bus+slot+function needed to be a "valid" PCI address, meaning
that at least one of domain/bus/slot had to be non-0), the RNG
required bus to be specified, and if type was set to PCI when
formatting, domain+bus+slot+function would always be output.
This makes all the address attributes optional during parse and RNG
validation, and suppresses domain+bus+slot+function if domain+bus+slot
are all 0 (NB: if d+b+s are all 0, any value for function is
nonsensical as that will never happen in the real world, and after
the next patch we will always assign a real working address to any
empty PCI address before it is ever output to anywhere).
Note that explicitly setting all attributes to 0 is equivalent to
setting none of them, which is okay, since 0000:00:00 is reserved in
any PCI bus setup, and can't be used anyway.
We support omitting listen attribute of graphics element so we should
also support omitting address attribute of listen element. This patch
also updates libvirt to always add a listen element into domain XML
except for VNC graphics if socket attribute is specified.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
SRIOV VFs used in macvtap passthrough mode can take advantage of the
SRIOV card's transparent vlan tagging. All the code was there to set
the vlan tag, and it has been used for SRIOV VFs used for hostdev
interfaces for several years, but for some reason, the vlan tag for
macvtap passthrough devices was stubbed out with a -1.
This patch moves a bit of common validation down to a lower level
(virNetDevReplaceNetConfig()) so it is shared by hostdev and macvtap
modes, and updates the macvtap caller to actually send the vlan config
instead of -1.
Add the ability to add an 'iothread' to the controller which will be how
virtio-scsi-pci and virtio-scsi-ccw iothreads have been implemented in qemu.
Describe the new functionality and add tests to parse/validate that the
new attribute can be added.
Rather than be specific about which devices in the <iothreads> description,
let's leave that for the <disk> description for it's <iothread> value.
Signed-off-by: John Ferlan <jferlan@redhat.com>
This adds a ports= attribute to usb controller XML, like
<controller type='usb' model='nec-xhci' ports='8'/>
This maps to:
qemu -device nec-usb-xhci,p2=8,p3=8
Meaning, 8 ports that support both usb2 and usb3 devices. Gerd
suggested to just expose them as one knob.
https://bugzilla.redhat.com/show_bug.cgi?id=1271408
If a panic device is being defined without a model in a domain
the default value is always overwritten with model ISA. An ISA
bus does not exist on S390 and therefore specifying a panic device
results in an unsupported configuration.
Since the S390 architecture inherently provides a crash detection
capability the panic device should be defined in the domain xml.
This patch adds an s390 panic device model and prevents setting a
device address on it.
Signed-off-by: Boris Fiuczynski <fiuczy@linux.vnet.ibm.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
This reverts commit 690969af9c, which
added the domain config parts to support a "peer" attribute in domain
interface <ip> elements.
It's being removed temporarily for the release of libvirt 1.3.4
because the feature doesn't work, and there are concerns that it may
need to be modified in an externally visible manner which could create
backward compatibility problems.
Currently we only allow /dev/random and /dev/hwrng as host input
for <rng><backend model='random'/> device. This was added after
various upstream discussions in commit 4932ef45
However this restriction has generated quite a few complaints over
the years, so a new discussion was initiated:
http://www.redhat.com/archives/libvir-list/2016-April/msg00987.html
Several people suggested removing the restriction, and nobody really
spoke up to defend it. So this patch drops the path restriction
entirely
https://bugzilla.redhat.com/show_bug.cgi?id=1074464
When describing attributes and elements, we mostly stick to
a certain pattern; however, there are a few cases when the
information is not presented in the usual way.
Since there doesn't seem to be any reason not to follow the
tried and true formula, rework those bits to fit the rest of
the documentation.
This controller provides a single PCIe port on a new root. It is
similar to pci-expander-bus, intended to provide a bus that can be
associated with a guest-identifiable NUMA node, but is for
machinetypes with PCIe rather than PCI (e.g. q35-based machinetypes).
Aside from PCIe vs. PCI, the other main difference is that a
pci-expander-bus has a companion pci-bridge that is automatically
attached along with it, but pcie-expander-bus has only a single port,
and that port will only connect to a pcie-root-port, or to a
pcie-switch-upstream-port. In order for the bus to be of any use in
the guest, it must have either a pcie-root-port or a
pcie-switch-upstream-port attached (and one or more
pcie-switch-downstream-ports attached to the
pcie-switch-upstream-port).
This is a standard PCI root bus (not a bridge) that can be added to a
440fx-based domain. Although it uses a PCI slot, this is *not* how it
is connected into the PCI bus hierarchy, but is only used for
control. Each pci-expander-bus provides 32 slots (0-31) that can
accept hotplug of standard PCI devices.
The usefulness of pci-expander-bus relative to a pci-bridge is that
the NUMA node of the bus can be specified with the <node> subelement
of <target>. This gives guest-side visibility to the NUMA node of
attached devices (presuming that management apps only assign a device
to a bus that has a NUMA node number matching the node number of the
device on the host).
Each pci-expander-bus also has a "busNr" attribute. The expander-bus
itself will take the busNr specified, and all buses that are connected
to this bus (including the pci-bridge that is automatically added to
any expander bus of model "pxb" (see the next commit)) will use
busNr+1, busNr+2, etc, and the pci-root (or the expander-bus with next
lower busNr) will use bus numbers lower than busNr.
This cleanups the documentation, reformat some of the paragraphs to use
<p> instead of </br> and rewrites the listen part to be more extendable.
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
In order to follow recent comments which indicate support for specific
feature bits are supported by a specific QEMU version add the version
from whence the relaxed, vapic, and spinlocks support was added.
This patch adds support for "vpindex", "runtime", "synic",
"stimer", and "vendor_id" features available in qemu 2.5+.
- When Hyper-V "vpindex" is on, guest can use MSR HV_X64_MSR_VP_INDEX
to get virtual processor ID.
- Hyper-V "runtime" enlightement feature allows to use MSR
HV_X64_MSR_VP_RUNTIME to get the time the virtual processor consumes
running guest code, as well as the time the hypervisor spends running
code on behalf of that guest.
- Hyper-V "synic" stands for Synthetic Interrupt Controller, which is
lapic extension controlled via MSRs.
- Hyper-V "stimer" switches on Hyper-V SynIC timers MSR's support.
Guest can setup and use fired by host events (SynIC interrupt and
appropriate timer expiration message) as guest clock events
- Hyper-V "reset" allows guest to reset VM.
- Hyper-V "vendor_id" exposes hypervisor vendor id to guest.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Signed-off-by: John Ferlan <jferlan@redhat.com>
Most hypervisors use Hardware Assisted Paging by default and don't
require specifying the feature in domain conf. But some hypervisors
support disabling HAP on a per-domain basis. To enable HAP by default
yet provide a knob to disable it, extend the <hap> feature with a
'state=on|off' attribute, similar to <pvspinlock> and <vmport> features.
In the absence of <hap>, the hypervisor default (on) is used. <hap>
without the state attribute would be the same as <hap state='on'/> for
backwards compatibility. And of course <hap state='off'/> disables hap.
Signed-off-by: Jim Fehlig <jfehlig@suse.com>
