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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<h1>Node devices XML format</h1>
<ul id="toc"></ul>
<h2><a id="NodedevAttributes">Node Device XML</a></h2>
<p>
There are several libvirt functions, all with the
prefix <code>virNodeDevice</code>, which deal with management of
host devices that can be handed to guests via passthrough as
&lt;hostdev&gt; elements
in <a href="formatdomain.html#elementsHostDev">the domain XML</a>.
These devices are represented as a hierarchy, where a device on
a bus has a parent of the bus controller device; the root of the
hierarchy is the node named "computer".
</p>
<p>
When represented in XML, a node device uses the
top-level <code>device</code> element, with the following
elements present according to the type of device:
</p>
<dl>
<dt><code>name</code></dt>
<dd>The name for this device. The name will be alphanumeric,
with words separated by underscore. For many devices, the
name is just the bus type and address, as in
"pci_0000_00_02_1" or "usb_1_5_3", but some devices are able
to provide more specific names, such as
"net_eth1_00_27_13_6a_fe_00". This is a read-only field that is
reported by the device driver. If this element is set when defining a
new device, it will be ignored.
</dd>
<dt><code>path</code></dt>
<dd>
Fully qualified sysfs path to the device. This is a read-only field
that is reported by the device driver. If this element is set when
defining a new device, it will be ignored.
</dd>
<dt><code>parent</code></dt>
<dd>
This element identifies the parent node in the device hierarchy. The
value of the element will correspond with the device parent's
<code>name</code> element or <code>computer</code> if the device does
not have any parent.
</dd>
<dt><code>driver</code></dt>
<dd>
This elements reports the driver in use for this device. The presence
of this element in the output XML depends on whether the underlying
device manager (most likely udev) exposes information about the
driver.
</dd>
<dt><code>devnode</code></dt>
<dd>This node appears for each associated <code>/dev</code>
special file. A mandatory attribute <code>type</code> specify
the kind of file path, which may be either <code>dev</code> for
the main name, or <code>link</code> for additional symlinks.
</dd>
<dt><code>capability</code></dt>
<dd>This node appears for each capability that libvirt
associates with a node. A mandatory
attribute <code>type</code> lists which category the device
belongs to, and controls which further subelements will be
present to describe the node:
<dl>
<dt><code>system</code></dt>
<dd>Describes the overall host. Sub-elements include:
<dl>
<dt><code>product</code></dt>
<dd>If present, a simple text string giving the product
name of the system.</dd>
<dt><code>hardware</code></dt>
<dd>Describes the hardware of the system, including
sub-elements for <code>vendor</code>, <code>version</code>,
<code>serial</code>, and <code>uuid</code>.</dd>
<dt><code>firmware</code></dt>
<dd>Describes the firmware of the system, including
sub-elements for <code>vendor</code>, <code>version</code>,
and <code>release_date</code>.</dd>
</dl>
</dd>
<dt><code>pci</code></dt>
<dd>Describes a device on the host's PCI bus. Sub-elements
include:
<dl>
<dt><code>class</code></dt>
<dd>Optional element for combined class, subclass and
programming interface codes as 6-digit hexadecimal number.
<span class="since">Since 5.2.0</span></dd>
<dt><code>domain</code></dt>
<dd>Which domain the device belongs to.</dd>
<dt><code>bus</code></dt>
<dd>Which bus within the domain.</dd>
<dt><code>slot</code></dt>
<dd>Which slot within the bus.</dd>
<dt><code>function</code></dt>
<dd>Which function within the slot.</dd>
<dt><code>product</code></dt>
<dd>Product details from the device ROM, including an
attribute <code>id</code> with the hexadecimal product
id, and an optional text description of that id.</dd>
<dt><code>vendor</code></dt>
<dd>Vendor details from the device ROM, including an
attribute <code>id</code> with the hexadecimal vendor
id, and an optional text name of that vendor.</dd>
<dt><code>iommuGroup</code></dt>
<dd>
This optional element describes the "IOMMU group" this
device belongs to. If the element exists, it has a
mandatory <code>number</code> attribute which tells
the group number used for management of the group (all
devices in group "n" will be found in
"/sys/kernel/iommu_groups/n"). It will also have a
list of <code>address</code> subelements, each
containing the PCI address of a device in the same
group. The toplevel device will itself be included in
this list.
</dd>
<dt><code>capability</code></dt>
<dd>
This optional element can occur multiple times. If it
exists, it has a mandatory <code>type</code> attribute
which will be set to:
<dl>
<dt><code>phys_function</code></dt>
<dd>
That means there will be a single <code>address</code>
subelement which contains the PCI address of the SRIOV
Physical Function (PF) that is the parent of this device
(and this device is, by implication, an SRIOV Virtual
Function (VF)).
</dd>
<dt><code>virt_functions</code></dt>
<dd>
In this case this device is an SRIOV PF, and the capability
element will have a list of <code>address</code>
subelements, one for each VF on this PF. If the host system
supports reporting it (via the "sriov_totalvfs" file in the
device's sysfs directory) the capability element will also
have an attribute named <code>maxCount</code> which is the
maximum number of SRIOV VFs supported by this device, which
could be higher than the number of VFs that are currently
active <span class="since">since 1.3.0</span>; in this case,
even if there are currently no active VFs the
virtual_functions capabililty will still be shown.
</dd>
<dt><code>pci-bridge</code> or <code>cardbus-bridge</code></dt>
<dd>
This shows merely that the lower 7 bits of PCI header type
have either value of 1 or 2 respectively. Usually this
means such device cannot be used for PCI passthrough.
<span class="since">Since 1.3.3</span>
</dd>
<dt><code><a id="MDEVTypesCapPCI">mdev_types</a></code></dt>
<dd>
This device is capable of creating mediated devices.
The sub-elements are summarized in
<a href="#MDEVTypesCap">mdev_types capability</a>.
</dd>
<dt><code><a id="VPDCapPCI">vpd</a></code></dt>
<dd>
This device exposes a VPD PCI/PCIe capability.
The sub-elements are summarized in
<a href="#VPDCap">vpd capability</a>.
</dd>
</dl>
</dd>
<dt><code>numa</code></dt>
<dd>
This optional element contains information on the PCI device
with respect to NUMA. For example, the optional
<code>node</code> attribute tells which NUMA node is the PCI
device associated with.
</dd>
<dt><code>pci-express</code></dt>
<dd>
This optional element contains information on PCI Express part of
the device. For example, it can contain a child element
<code>link</code> which addresses the PCI Express device's link.
While a device has its own capabilities
(<code>validity='cap'</code>), the actual run time capabilities
are negotiated on the device initialization
(<code>validity='sta'</code>). The <code>link</code> element then
contains three attributes: <code>port</code> which says in which
port is the device plugged in, <code>speed</code> (in
GigaTransfers per second) and <code>width</code> for the number
of lanes used. Since the port can't be negotiated, it's not
exposed in <code>./pci-express/link/[@validity='sta']</code>.
</dd>
</dl>
</dd>
<dt><code>usb_device</code></dt>
<dd>Describes a device on the host's USB bus, based on its
location within the bus. Sub-elements include:
<dl>
<dt><code>bus</code></dt>
<dd>Which bus the device belongs to.</dd>
<dt><code>device</code></dt>
<dd>Which device within the bus.</dd>
<dt><code>product</code></dt>
<dd>Product details from the device ROM, including an
attribute <code>id</code> with the hexadecimal product
id, and an optional text description of that id.</dd>
<dt><code>vendor</code></dt>
<dd>Vendor details from the device ROM, including an
attribute <code>id</code> with the hexadecimal vendor
id, and an optional text name of that vendor.</dd>
</dl>
</dd>
<dt><code>usb</code></dt>
<dd>Describes a USB device, based on its advertised driver
interface. Sub-elements include:
<dl>
<dt><code>number</code></dt>
<dd>The device number.</dd>
<dt><code>class</code></dt>
<dd>The device class.</dd>
<dt><code>subclass</code></dt>
<dd>The device subclass.</dd>
<dt><code>protocol</code></dt>
<dd>The device protocol.</dd>
<dt><code>description</code></dt>
<dd>If present, a description of the device.</dd>
</dl>
</dd>
<dt><code>net</code></dt>
<dd>Describes a device capable for use as a network
interface. Sub-elements include:
<dl>
<dt><code>interface</code></dt>
<dd>The interface name tied to this device.</dd>
<dt><code>address</code></dt>
<dd>If present, the MAC address of the device.</dd>
<dt><code>link</code></dt>
<dd>Optional to reflect the status of the link. It has
two optional attributes: <code>speed</code> in Mbits per
second and <code>state</code> to tell the state of the
link. So far, the whole element is just for output,
not setting.
</dd>
<dt><code>feature</code></dt>
<dd>If present, the hw offloads supported by this network
interface. Possible features are:
<dl>
<dt><code>rx</code></dt><dd>rx-checksumming</dd>
<dt><code>tx</code></dt><dd>tx-checksumming</dd>
<dt><code>sg</code></dt><dd>scatter-gather</dd>
<dt><code>tso</code></dt><dd>tcp-segmentation-offload</dd>
<dt><code>ufo</code></dt><dd>udp-fragmentation-offload</dd>
<dt><code>gso</code></dt><dd>generic-segmentation-offload</dd>
<dt><code>gro</code></dt><dd>generic-receive-offload</dd>
<dt><code>lro</code></dt><dd>large-receive-offload</dd>
<dt><code>rxvlan</code></dt><dd>rx-vlan-offload</dd>
<dt><code>txvlan</code></dt><dd>tx-vlan-offload</dd>
<dt><code>ntuple</code></dt><dd>ntuple-filters</dd>
<dt><code>rxhash</code></dt><dd>receive-hashing</dd>
<dt><code>rdma</code></dt><dd>remote-direct-memory-access</dd>
<dt><code>txudptnl</code></dt><dd>tx-udp-tunnel-segmentation</dd>
<dt><code>switchdev</code></dt><dd>kernel-forward-plane-offload</dd>
</dl>
</dd>
<dt><code>capability</code></dt>
<dd>A network protocol exposed by the device, where the
attribute <code>type</code> can be "80203" for IEEE
802.3, or "80211" for various flavors of IEEE 802.11.
</dd>
</dl>
</dd>
<dt><code>scsi_host</code></dt>
<dd>Describes a SCSI host device. Sub-elements include:
<dl>
<dt><code>host</code></dt>
<dd>The SCSI host number.</dd>
<dt><code>unique_id</code></dt>
<dd>On input, this optionally provides the value from the
'unique_id' file found in the scsi_host's directory. To
view the values of all 'unique_id' files, use <code>find -H
/sys/class/scsi_host/host{0..9}/unique_id |
xargs grep '[0-9]'</code>. On output, if the unique_id
file exists, the value from the file will be displayed.
This can be used in order to help uniquely identify the
scsi_host adapter in a <a href="formatstorage.html">
Storage Pool</a>. <span class="since">Since 1.2.7</span>
</dd>
<dt><code>capability</code></dt>
<dd>Current capabilities include "vports_ops" (indicates
vport operations are supported) and "fc_host". "vport_ops"
could contain two optional sub-elements: <code>vports</code>,
and <code>max_vports</code>. <code>vports</code> shows the
number of vport in use. <code>max_vports</code> shows the
maximum vports the HBA supports. "fc_host" implies following
sub-elements: <code>wwnn</code>, <code>wwpn</code>, and
optionally <code>fabric_wwn</code>.
</dd>
</dl>
</dd>
<dt><code>scsi</code></dt>
<dd>Describes a SCSI device. Sub-elements include:
<dl>
<dt><code>host</code></dt>
<dd>The SCSI host containing the device.</dd>
<dt><code>bus</code></dt>
<dd>The bus within the host.</dd>
<dt><code>target</code></dt>
<dd>The target within the bus.</dd>
<dt><code>lun</code></dt>
<dd>The lun within the target.</dd>
<dt><code>type</code></dt>
<dd>The type of SCSI device.</dd>
</dl>
</dd>
<dt><code>storage</code></dt>
<dd>Describes a device usable for storage. Sub-elements
include:
<dl>
<dt><code>block</code></dt>
<dd>A block device file name that accesses the storage
present on the device.</dd>
<dt><code>bus</code></dt>
<dd>If present, the name of the bus the device is found
on.</dd>
<dt><code>drive_type</code></dt>
<dd>The type of the drive, such as "disk" or
"cdrom".</dd>
<dt><code>model</code></dt>
<dd>Any model information available from the
device.</dd>
<dt><code>vendor</code></dt>
<dd>Any vendor information available from the
device.</dd>
<dt><code>serial</code></dt>
<dd>Any serial number information available from the
device.</dd>
<dt><code>size</code></dt>
<dd>For fixed-size storage, the amount of storage
available.</dd>
<dt><code>capability</code></dt>
<dd>If present, an additional capability is listed via
the attribute <code>type</code>. Current capabilities
include "hotpluggable" and "removable", with the
latter implying the following
sub-elements: <code>media_available</code> (0 or
1), <code>media_size</code>,
and <code>media_label</code>.</dd>
</dl>
</dd>
<dt><code>drm</code></dt>
<dd>Describes a Direct Rendering Manager (DRM) device.
Sub-elements include:
<dl>
<dt><code>type</code></dt>
<dd>The type of DRM device. Could be
<code>primary</code>, <code>control</code> or
<code>render</code>.</dd>
</dl>
</dd>
<dt><a id="mdev"><code>mdev</code></a></dt>
<dd>Describes a mediated device. <span class="since">Since
3.4.0</span> Sub-elements include:
<dl>
<dt><code>type</code></dt>
<dd>
Describes a mediated device type which acts as an abstract
template defining a resource allocation for instances
of this device type. The element has one attribute
<code>id</code> which holds an official vendor-supplied
identifier for the type.
</dd>
<dt><code>iommuGroup</code></dt>
<dd>
This element supports a single attribute <code>number</code>
which holds the IOMMU group number to which the mediated device
belongs. This is a read-only field that is reported by the
device driver.
</dd>
<dt><code>attr</code></dt>
<dd>
This optional element can occur multiple times. It represents a
vendor-specific attribute that is used to configure this
mediated device. It has two required attributes:
<code>name</code> and <code>value</code>. Note that the order
in which attributes are set may be important for some devices.
The order that they appear in the xml definition determines the
order that they will be written to the device.
</dd>
<dt><code>uuid</code></dt>
<dd>
This element represents the UUID of the mediated device.
</dd>
</dl>
</dd>
<dt><code>ccw</code></dt>
<dd>Describes a Command Channel Word (CCW) device commonly found on
the S390 architecture. Sub-elements include:
<dl>
<dt><code>cssid</code></dt>
<dd>The channel subsystem identifier.</dd>
<dt><code>ssid</code></dt>
<dd>The subchannel-set identifier.</dd>
<dt><code>devno</code></dt>
<dd>The device number.</dd>
</dl>
</dd>
<dt><code>css</code></dt>
<dd>Describes a subchannel in the Channel SubSystem (CSS) commonly
found on the S390 architecture. Sub-elements include:
<dl>
<dt><code>cssid</code></dt>
<dd>The channel subsystem identifier.</dd>
<dt><code>ssid</code></dt>
<dd>The subchannel-set identifier.</dd>
<dt><code>devno</code></dt>
<dd>The subchannel number.</dd>
<dt><code>capability</code></dt>
<dd>
This optional element can occur multiple times. If it
exists, it has a mandatory <code>type</code> attribute
which will be set to:
<dl>
<dt><code><a id="MDEVTypesCapCSS">mdev_types</a></code></dt>
<dd>
<span class="since">Since 6.10.0</span>
This device is capable of creating mediated devices.
The sub-elements are summarized in
<a href="#MDevTypesCap">mdev_types capability</a>.
</dd>
</dl>
</dd>
</dl>
</dd>
<dt><code>vdpa</code></dt>
<dd>Describes a virtual datapath acceleration (vDPA) network device.
<span class="since">Since 6.9.0</span>. Sub-elements include:
<dl>
<dt><code>chardev</code></dt>
<dd>The path to the character device that is used to access the
device.</dd>
</dl>
</dd>
<dt><code>ap_card</code></dt>
<dd>Describes the Adjunct Processor (AP) Card device on a S390 host.
Sub-elements include:
<dl>
<dt><code>ap-adapter</code></dt>
<dd>AP Card identifier.</dd>
</dl>
</dd>
<dt><code>ap_queue</code></dt>
<dd>Describes the AP queue on a s390 host. An AP queue is
an AP domain on an AP adapter which is specified by an
adapter identifier and a domain identifier.
Sub-elements include:
<dl>
<dt><code>ap-adapter</code></dt>
<dd>The ap-adapter of an AP queue identifies the AP
card to which this AP queue belongs.</dd>
<dt><code>ap-domain</code></dt>
<dd>The ap-domain of an AP queue identifies the AP
domain to which this AP queue belongs.</dd>
<dd>AP Queue identifier.</dd>
</dl>
</dd>
<dt><code>ap_matrix</code></dt>
<dd>Describes an AP Matrix device on a S390 architecture providing
cryptographic host resources usable for virtualization.
Sub-elements include:
<dl>
<dt><code>capability</code></dt>
<dd>
This optional element can occur multiple times. If it
exists, it has a mandatory <code>type</code> attribute
which will be set to:
<dl>
<dt><code><a id="MDEVTypesCapAP">mdev_types</a></code></dt>
<dd>
<span class="since">Since 6.10.0</span>
This device is capable of creating mediated devices.
The sub-elements are summarized in
<a href="#MDEVTypesCap">mdev_types capability</a>.
</dd>
</dl>
</dd>
</dl>
</dd>
</dl>
</dd>
</dl>
<h3><a id="MDEVTypesCap">mdev_types capability</a></h3>
<p>
<a href="#MDEVTypesCapPCI">PCI</a>, <a href="#MDEVTypesCapCSS">CSS</a>
and <a href="#MDEVTypesCapAP">AP Matrix</a>
devices can be capable of creating mediated devices.
If they indeed are capable, then the parent <code>capability</code>
element for <code>mdev_types</code> type will contain a list of
<code>type</code> elements, which list all mdev types supported
on the physical device. <span class="since">Since 3.4.0</span>
Each <code>type</code> element has a single <code>id</code>
attribute that holds an official vendor-supplied identifier
for the type. It supports the following sub-elements:
<dl>
<dt><code>name</code></dt>
<dd>
The <code>name</code> element holds a vendor-supplied
code name for the given mediated device type. This is
an optional element.
</dd>
<dt><code>deviceAPI</code></dt>
<dd>
The value of this element describes how an instance of
the given type will be presented to the guest by the
VFIO framework.
</dd>
<dt><code>availableInstances</code></dt>
<dd>
This element reports the current state of resource
allocation. In other words, how many instances of the
given type can still be successfully created on the
physical device.
</dd>
</dl>
</p>
<h3><a id="VPDCap">vpd capability</a></h3>
<p>
<a href="#VPDCapPCI">PCI</a> devices can expose a VPD capability which
is optional per PCI Local Bus 2.2+ and PCIe 4.0+ specifications. If
the VPD capability is present, then the parent <code>capability</code>
element with the <code>vpd</code> type will contain a <code>name</code>
element (containing a manufacturer-provided device name) and optionally
one or two <code>fields</code> elements with an <code>access</code>
attribute set to <code>readonly</code> or <code>readwrite</code>.
</p>
<p>
The read-only <code>fields</code> element may contain the following elements:
<dl>
<dt><code>change_level</code></dt>
<dd>An engineering change level for this add-in card.</dd>
<dt><code>manufacture_id</code></dt>
<dd>An extension to the Vendor ID (or Subsystem Vendor ID) in the
Configuration Space header which allows vendors the flexibility to identify
an additional level of detail pertaining to the sourcing of a PCI device.</dd>
<dt><code>part_number</code></dt>
<dd>An extension to the Device ID (or Subsystem ID) in the Configuration
Space header specifying a part number of an add-in card.</dd>
<dt><code>serial_number</code></dt>
<dd>A unique add-in card Serial Number.</dd>
<dt><code>vendor_field</code></dt>
<dd>Zero or many of those elements with an <code>index</code> attribute
(since-character upper-case ASCII alphanumeric indexes). Contents will vary
depending on a vendor.</dd>
</dl>
All fields are optional and are not guaranteed to be present for a generic PCI device.
</p>
<p>
The read-write <code>fields</code> element may contain the following elements:
<dl>
<dt><code>asset_tag</code></dt>
<dd>A system asset identifier provided by the system owner.</dd>
<dt><code>vendor_field</code></dt>
<dd>Zero or many of those elements with an <code>index</code> attribute
(since-character upper-case ASCII alphanumeric indexes). Contents will vary depending
on a vendor.</dd>
<dt><code>system_field</code></dt>
<dd>Zero or many of those elements with an <code>index</code> attribute (since-character
upper-case ASCII alphanumeric indexes, except for letter 'A'). May store system-specific
data related to a PCI device.</dd>
</dl>
All fields are optional and are not guaranteed to be present for a generic PCI device.
Read-write fields are not possible to alter via Libvirt at the time of writing but their
content is refreshed on each invocation in case this is done by means external to Libvirt.
</p>
<p>
The device name and all fields may contain only the following characters:
<code>[0-9a-zA-F -_,.:;=]</code>.
The device name may be as large as 65535 bytes while fields are limited with 255 bytes.
</p>
<h2><a id="nodeExample">Examples</a></h2>
<p>The following are some example node device XML outputs:</p>
<pre>
&lt;device&gt;
&lt;name&gt;computer&lt;/name&gt;
&lt;capability type='system'&gt;
&lt;product&gt;2241B36&lt;/product&gt;
&lt;hardware&gt;
&lt;vendor&gt;LENOVO&lt;/vendor&gt;
&lt;version&gt;ThinkPad T500&lt;/version&gt;
&lt;serial&gt;R89055N&lt;/serial&gt;
&lt;uuid&gt;c9488981-5049-11cb-9c1c-993d0230b4cd&lt;/uuid&gt;
&lt;/hardware&gt;
&lt;firmware&gt;
&lt;vendor&gt;LENOVO&lt;/vendor&gt;
&lt;version&gt;6FET82WW (3.12 )&lt;/version&gt;
&lt;release_date&gt;11/26/2009&lt;/release_date&gt;
&lt;/firmware&gt;
&lt;/capability&gt;
&lt;/device&gt;
&lt;device&gt;
&lt;name&gt;net_eth1_00_27_13_6a_fe_00&lt;/name&gt;
&lt;parent&gt;pci_0000_00_19_0&lt;/parent&gt;
&lt;capability type='net'&gt;
&lt;interface&gt;eth1&lt;/interface&gt;
&lt;address&gt;00:27:13:6a:fe:00&lt;/address&gt;
&lt;capability type='80203'/&gt;
&lt;/capability&gt;
&lt;/device&gt;
&lt;device&gt;
&lt;name&gt;pci_0000_02_00_0&lt;/name&gt;
&lt;path&gt;/sys/devices/pci0000:00/0000:00:04.0/0000:02:00.0&lt;/path&gt;
&lt;parent&gt;pci_0000_00_04_0&lt;/parent&gt;
&lt;driver&gt;
&lt;name&gt;igb&lt;/name&gt;
&lt;/driver&gt;
&lt;capability type='pci'&gt;
&lt;class&gt;0x020000&lt;/class&gt;
&lt;domain&gt;0&lt;/domain&gt;
&lt;bus&gt;2&lt;/bus&gt;
&lt;slot&gt;0&lt;/slot&gt;
&lt;function&gt;0&lt;/function&gt;
&lt;product id='0x10c9'&gt;82576 Gigabit Network Connection&lt;/product&gt;
&lt;vendor id='0x8086'&gt;Intel Corporation&lt;/vendor&gt;
&lt;capability type='virt_functions'&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x10' function='0x0'/&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x10' function='0x2'/&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x10' function='0x4'/&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x10' function='0x6'/&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x11' function='0x0'/&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x11' function='0x2'/&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x11' function='0x4'/&gt;
&lt;/capability&gt;
&lt;iommuGroup number='12'&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x00' function='0x0'/&gt;
&lt;address domain='0x0000' bus='0x02' slot='0x00' function='0x1'/&gt;
&lt;/iommuGroup&gt;
&lt;pci-express&gt;
&lt;link validity='cap' port='1' speed='2.5' width='1'/&gt;
&lt;link validity='sta' speed='2.5' width='1'/&gt;
&lt;/pci-express&gt;
&lt;/capability&gt;
&lt;/device&gt;
</pre>
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