news.xml

<?xml version="1.0"?>

<!-- libvirt release notes

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  <release version="FIXME" date="unreleased">
    <section title="New features">
    </section>
    <section title="Improvements">
    </section>
    <section title="Bug fixes">
    </section>
  </release>

     -->

<libvirt>
  <release version="v4.4.0" date="unreleased">
    <section title="New features">
      <change>
        <summary>
          bhyve: Support locking guest memory
        </summary>
        <description>
          Bhyve's guest memory may be wired using the
          <code>&lt;memoryBacking&gt;&lt;locked/&gt;&lt;/memoryBacking&gt;</code>
          element.
        </description>
      </change>
      <change>
        <summary>
          qemu: Provide VFIO channel I/O passthrough support
        </summary>
        <description>
          Support passthrough devices that use channel I/O based mechanism in
          a QEMU virtual machine.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for migration of VMs with non-shared storage over TLS
        </summary>
        <description>
          It's now possible to use the VIR_MIGRATE_TLS flag together with
          VIR_MIGRATE_NON_SHARED_DISK. The connection is then secured using the
          TLS environment which is setup for the migration connection.
        </description>
      </change>
      <change>
        <summary>
          Add support for VM Generation ID
        </summary>
        <description>
          The VM Generatation ID exposes a 128-bit, cryptographically
          random, integer value identifier, referred to as a Globally
          Unique Identifier (GUID) to the guest in order to notify the
          guest operating system when the virtual machine is executed
          with a different configuration. Add a new domain XML processing
          and a domain capabilities feature.
        </description>
      </change>
      <change>
        <summary>
          Introduce virDomainDetachDeviceAlias
        </summary>
        <description>
          This new API enables users to detach device using only its alias.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: Add suport for OpenGL rendering with SDL
        </summary>
        <description>
          Domains using SDL as a graphics backend will now be able to use
          OpenGL accelerated rendering.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for 'output' audio codec
        </summary>
        <description>
          Support QEMU's 'hda-output' codec advertising only a line-out for ich6
          and ich9 sound devices.
        </description>
      </change>
      <change>
        <summary>
          virsh: Enhance event name completion
        </summary>
        <description>
          Implement event name completion for some commands (e.g. event,
          secret-event, pool-event and nodedev-event)
        </description>
      </change>
    </section>
    <section title="Bug fixes">
    </section>
  </release>
  <release version="v4.3.0" date="2018-05-02">
    <section title="New features">
      <change>
        <summary>
          qemu: Add support for the pcie-to-pci-bridge controller
        </summary>
        <description>
          Pure PCIe guests such as x86_64/q35 and aarch64/virt will now
          add this controller when traditional PCI devices are in use.
        </description>
      </change>
      <change>
        <summary>
          Xen: Support setting CPU features for host-passthrough model
        </summary>
        <description>
          The CPU model presented to Xen HVM domains is equivalent to libvirt's
          host-passthrough model, although individual features can be enabled
          and disabled via the cpuid setting. The libvirt libxl driver now
          supports enabling and disabling individual features of the
          host-passthrough CPU model.
        </description>
      </change>
    </section>
    <section title="Removed features">
      <change>
        <summary>
          Xen: Drop the legacy xend-based driver
        </summary>
        <description>
          The xm/xend toolstack was deprecated in Xen 4.2 and removed
          from the Xen sources in the 4.5 development cycle. The libvirt
          driver based on xend is now removed from the libvirt sources.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: Support hot plug and hot unplug of mediated devices
        </summary>
        <description>
          Libvirt now allows mediated devices to be hot plugged and hot
          unplugged from a guest rather than reporting an error that this isn't
          supported. In fact, kernel has been supporting this since 4.10.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          Improve handling of device mapper targets
        </summary>
        <description>
          When starting a domain with a disk backed by a device
          mapper volume libvirt also needs to allow the storage
          backing the device mapper in CGroups. In the past
          kernel did not care, but starting from 4.16 CGroups are
          consulted on each access to the device mapper target.
        </description>
      </change>
    </section>
  </release>
  <release version="v4.2.0" date="2018-04-01">
    <section title="New features">
      <change>
        <summary>
          Support building with Python 3
        </summary>
        <description>
          Python is required to build libvirt, and up until now only Python 2
          could be used as an interpreter. All scripts used during build have
          now been made compatible with Python 3, which means both major
          releases of the language are fully supported.
        </description>
      </change>
      <change>
        <summary>
          qemu: Provide ccw address support for graphics and input devices
        </summary>
        <description>
          Support the virtio-gpu-ccw device as a video device and
          virtio-{keyboard, mouse, tablet}-ccw devices as input devices
          on S390.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: Add logging of guest crash information on S390
        </summary>
        <description>
          On S390, when the guest crashes and QEMU exposes the guest crash
          information, log the relevant data to the domain log file.
        </description>
      </change>
      <change>
        <summary>
          qemu: use arp table of host to get the IP address of guests
        </summary>
        <description>
          Find IP address of a VM by arp table on hosts.
          If someone customizing IP address inside VM, it will be helpful.
        </description>
      </change>
      <change>
        <summary>
          Xen: Remove hard-coded scheduler weight
        </summary>
        <description>
          The libxl driver was accidentally hard-coding the per-domain
          scheduler weight to 1000, silently ignoring any user-provided
          <code>&lt;shares&gt;</code> in <code>&lt;cputune&gt;</code>. The
          driver now honors <code>&lt;shares&gt;</code>, and defers setting
          a default value to Xen. Note that the Xen default is 256, so any
          domains started after this improvement will have one fourth the
          shares of previously started domains. If all domains must have
          equal CPU shares, administrators must manually set the weight of
          previously started domains to 256, or restart them.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          qemu: TLS migration now enforces use of TLS for the NBD connection
        </summary>
        <description>
          When the VIR_MIGRATE_TLS flag was used with the migration API libvirt
          did not ensure that the NBD connection was using TLS as well. The code
          now rejects such migration as the TLS transport for NBD is not ready
          yet, but prevents a false sense of security that TLS would be used.
          The support TLS for NBD will be added soon.
        </description>
      </change>
    </section>
  </release>
  <release version="v4.1.0" date="2018-03-05">
    <section title="New features">
      <change>
        <summary>
          Added support for CAT (Cache allocation Technology)
        </summary>
        <description>
          Domain vCPU threads can now have allocated some parts of host cache
          using the <code>cachetune</code> element in <code>cputune</code>.
        </description>
      </change>
      <change>
        <summary>
          Allow opening secondary drivers
        </summary>
        <description>
          Up until now it was possible to connect to only hypervisor drivers
          (e.g. qemu:///system, lxc:///, vbox:///system, and so on). The
          internal drivers (like network driver, node device driver, etc.) were
          hidden from users and users could use them only indirectly. Starting
          with this release new connection URIs are accepted. For instance
          network:///system, storage:///system and so on.
        </description>
      </change>
      <change>
        <summary>
          virtlogd, virtlockd: Add support for admin protocol
        </summary>
        <description>
          These two daemons now support admin protocol through which some admin
          info can be gathered or some configuration tweaked on the fly.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          virsh: Enhance bash completion
        </summary>
        <description>
          Implement more bash completions so that basic libvirt
          objects can be auto-completed (e.g. networks,
          interfaces, NWFilters, and so on).
        </description>
      </change>
      <change>
        <summary>
          qemu: Use VIR_ERR_DEVICE_MISSING for various hotplug/detach messages
        </summary>
      </change>
      <change>
        <summary>
          qemu: Allow showing the dump progress for memory only dump
        </summary>
        <description>
          Alter the QEMU dump-guest-memory command processing to check
          for and allow asynchronous completion which then allows for
          the virsh dump --memory-only --verbose command to display percent
          completion data.
        </description>
      </change>
      <change>
        <summary>
          conf: add support for setting Chassis SMBIOS data fields
        </summary>
      </change>
      <change>
        <summary>
          libxl: add support for setting clock offset and adjustment
        </summary>
      </change>
      <change>
        <summary>
          Make port allocator global
        </summary>
        <description>
          Up until now each driver had their own port allocator module. This
          meant that info on port usage was not shared. Starting with this
          release, the port allocator module is made global and therefore
          drivers allocate ports from global pool.
        </description>
      </change>
      <change>
        <summary>
          Fixed some compiler warnings that appear with GCC 8
        </summary>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          qemu: Check for unsafe migration more thoroughly
        </summary>
        <description>
          If a domain disk is stored on local filesystem (e.g. ext4) but is
          not being migrated it is very likely that domain is not able to
          run on destination. Regardless of share/cache mode.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix updating device with boot order
        </summary>
        <description>
          Starting with 3.7.0 release updating any device with boot order would
          fail with 'boot order X is already used by another device' while in
          fact it was the very same device.
        </description>
      </change>
      <change>
        <summary>
          virlog: determine the hostname on startup CVE-2018-6764
        </summary>
        <description>
          At later point it might not be possible or even safe to use
          getaddrinfo(). It can in turn result in a load of NSS module which
          can even be loaded from unsage guest filesystem and thus escape the
          confinment of its container.
        </description>
      </change>
      <change>
        <summary>
          qemu: Rework vCPU statistics fetching
        </summary>
        <description>
          Fetching vCPU statistics was very expensive because it lead to waking
          up vCPU threads in QEMU and thus it degraded performance. The code
          was reworked so that fetching statistics does not wake up halted
          vCPUs.
        </description>
      </change>
      <change>
        <summary>
          qemu: unlink memory backing file on domain shutdown
        </summary>
        <description>
          Depending on the filesystem where domain memory is stored, some files
          might have been left behind. This is not a problem on hugetlbfs, but
          it is a problem on regular filesystems like ext4.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix shutting down domains in parallel
        </summary>
        <description>
          If multiple domains were being shut down in parallel, libvirtd might
          have deadlocked.
        </description>
      </change>
      <change>
        <summary>
          nodedev: Update PCI mdev capabilities dynamically
        </summary>
        <description>
          PCI devices may have other nested capabilities, like SRIOV and mdev
          which depend on the device being plugged into the native vendor
          driver. However, in case such a device is directly assigned to a guest
          using VFIO driver, the device will naturally lose these capabilities
          and libvirt needs to reflect that.
        </description>
      </change>
    </section>
  </release>
  <release version="v4.0.0" date="2018-01-19">
    <section title="New features">
      <change>
        <summary>
          tools: Provide bash completion support
        </summary>
        <description>
          Both <code>virsh</code> and <code>virt-admin</code> now implement
          basic bash completion support.
        </description>
      </change>
      <change>
        <summary>
          qemu: Refresh capabilities on host microcode update
        </summary>
        <description>
          A microcode update can cause the CPUID bits to change; therefore,
          the capabilities cache should be rebuilt when such an update is
          detected on the host.
        </description>
      </change>
      <change>
        <summary>
          lxc: Set hostname based on container name
        </summary>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          CPU frequency reporting improvements
        </summary>
        <description>
          The CPU frequency will now be reported by <code>virsh nodeinfo</code>
          and other tools for s390 hosts; at the same time; CPU frequency has
          been disabled on aarch64 hosts because there's no way to detect it
          reliably.
        </description>
      </change>
      <change>
        <summary>
          libxl: Mark domain0 as persistent
        </summary>
      </change>
      <change>
        <summary>
          Xen: Add support for multiple IP addresses on interface devices
        </summary>
      </change>
      <change>
        <summary>
          qemu: Add support for hot unplugging redirdev device
        </summary>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          qemu: Enforce vCPU hotplug granularity constraints
        </summary>
        <description>
          QEMU 2.7 and newer don't allow guests to start unless the initial
          vCPUs count is a multiple of the vCPU hotplug granularity, so
          validate it and report an error if needed.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.10.0" date="2017-12-04">
    <section title="New features">
      <change>
        <summary>
          conf: Support defining distances between virtual NUMA cells
        </summary>
        <description>
          A NUMA hardware architecture supports the notion of distances
          between NUMA cells. This can now be specified using the
          <code>&lt;distances&gt;</code> element within the NUMA cell
          configuration. Drivers which support this include Xen and QEMU.
        </description>
      </change>
      <change>
        <summary>
          Xen: Support defining vNUMA topology
        </summary>
        <description>
          Xen now supports defining a virtual NUMA topology for VMs,
          including specifying distances between NUMA cells.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add the ability to configure HPT resizing for pSeries guests
        </summary>
        <description>
          The user can now decide whether HPT (Hash Page Table) resizing
          should be enabled, disabled or required instead of leaving it up to
          hypervisor defaults and negotiation between the guest and the host.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add vmcoreinfo feature
        </summary>
        <description>
          Starting with QEMU 2.11, the guest can save kernel debug
          details when this feature is enabled and the kernel supports
          it. It is useful to process kernel dump with KASLR enabled,
          and also provides various kernel details to crash tools.
        </description>
      </change>
      <change>
        <summary>
          conf: Move the auth and encryption definitions to disk source
        </summary>
        <description>
          Allow parsing and formatting of the <code>auth</code> and
          <code>encryption</code> sub-elements to be a child of the
          <code>source</code> element. This will allow adding an
          <code>auth</code> sub-element to a <code>backingStore</code>
          or <code>mirror</code> elements as a means to track specific
          authentication and/or encryption needs.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          vbox: Add VirtualBox 5.2 support
        </summary>
      </change>
      <change>
        <summary>
          vbox: Add support for configuring storage controllers
        </summary>
        <description>
          The VirtualBox driver now supports the <code>&lt;controller&gt;</code>
          element in the domain XML for configuring storage controllers in VBOX
          VMs.  Additionally, libvirt's domain XML schema was updated to allow
          optional <code>model</code> attribute for <code>&lt;controller
              type='ide'&gt;</code> which is used by the VBOX driver to set the
          IDE controller model to be one of 'piix4', 'piix4' (default), or
          'ich6'.  Finally, with this change <code>dumpxml</code> generates
          <code>&lt;controller&gt;</code> elements that correspond to current
          VBOX VM storage controller configuration.
        </description>
      </change>
      <change>
        <summary>
          vbox: Add support for attaching empty removable disks
        </summary>
        <description>
          The VirutalBox driver now supports adding CD-ROM and floppy disk
          devices that do not have the disk source specified. Previously such
          devices were silently ignored.
        </description>
      </change>
      <change>
        <summary>
          vbox: Add support for attaching SAS storage controllers
        </summary>
        <description>
          In VirtualBox, SCSI and SAS are distinct controller types whereas
          libvirt does not make such distinction. Therefore, the VBOX driver was
          updated to allow attaching SAS controllers via <code>&lt;controller
              type='scsi' model='lsisas1068'&gt;</code> element. If there are
          both SCSI and SAS controllers present in the VBOX VM, the domain XML
          can associate the disk device using the <code>&lt;address&gt;</code>
          element with the <code>controller</code> attribute, and optionally,
          set the port via <code>unit</code> attribute.
        </description>
      </change>
      <change>
        <summary>
          qemu: Generate predictable paths for qemu memory backends
        </summary>
        <description>
          In some cases management applications need to know
          paths passed to memory-backend-file objects upfront.
          Libvirt now generates predictable paths so applications
          can prepare the files if they need to do so.
        </description>
      </change>
      <change>
        <summary>
          Shareable disks work properly with recent qemu
        </summary>
        <description>
          Recent qemu versions added image locking to avoid potential corruption
          of disk images. This broke shareable disks with libvirt since the
          feature was turned on by default in qemu. Libvirt now enables sharing
          of those disks in qemu so that the image locking is not applied in
          that case. Additionally libvirt now checks that shareable disks have
          supported format (raw) to avoid metadata corruption.
        </description>
      </change>
      <change>
        <summary>
          Improve serial console behavior on non-x86 architectures
        </summary>
        <description>
          ppc64, aarch64 and s390x guests were treating the &lt;serial&gt;
          and &lt;console&gt; elements differently from x86, in some cases
          presenting misleading information to the user. The behavior is now
          consistent across all architectures and the information reported
          is always accurate.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          vbox: Do not ignore failures to attach disk devices when defining
        </summary>
        <description>
          The <code>define</code> now fails and reports an error if any of the
          <code>controller</code> or <code>disk</code> devices specified in the
          domain XML fail to attach to the VirtualBox VM.
        </description>
      </change>
      <change>
        <summary>
          vbox: Fix dumpxml to always output disk devices
        </summary>
        <description>
          The VirtualBox driver was ignoring any disk devices in
          <code>dumpxml</code> output if there was a SAS storage controller
          attached to the VM.
        </description>
      </change>
      <change>
        <summary>
          vbox: Fix dumpxml to always generate valid domain XML
        </summary>
        <description>
          When a VirtualBox VM has multiple disks attached, each to a different
          storage controller that uses 'sd' prefix for block device names e.g.
          one disk attached to SATA and one to SCSI controller, it no longer
          generates XML where both would have 'sda' device name assigned.
          Instead it properly assigns 'sda' and 'sdb' to those disks in the
          order of appearance.
        </description>
      </change>
      <change>
        <summary>
          Securely pass iSCSI authentication data
        </summary>
        <description>
          Rather than supplying the authentication data as part of the
          iSCSI URL for a disk or host device, utilize the encrypted
          secret object to securely pass the authentication data.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.9.0" date="2017-11-02">
    <section title="New features">
      <change>
        <summary>
          Add capability to allow hot (un)plug of a domain watchdog device
        </summary>
      </change>
      <change>
        <summary>
          Allow users to set device aliases
        </summary>
        <description>
          Users can set aliases to domain devices and thus identify them
          easily.
        </description>
      </change>
      <change>
        <summary>
          qemu: Support multiqueue for virtio-blk
        </summary>
        <description>
          Multiqueue support for <code>virtio-blk</code> has been available
          in QEMU ever since 2.7.0, and now libvirt guests can enable it.
        </description>
      </change>
      <change>
        <summary>
          Add virDomainSetLifecycleAction API
        </summary>
        <description>
          Provided a new API to allow dynamic guest lifecycle control for
          guest reactions to poweroff, restart, or crash type events related
          to the domain XML <code>on_poweroff</code>, <code>on_reboot</code>,
          and <code>on_crash</code> elements. The
          <code>virsh set-lifecycle-action</code> command was created to
          control the actions.
        </description>
      </change>
      <change>
        <summary>
          qemu: Allow cold(un)plugging and hot(un)plugging input devices
        </summary>
      </change>
      <change>
        <summary>
          net: Implement QoS for vhostuser
        </summary>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          Allow a logical volume to be create using LUKS
        </summary>
        <description>
          A logical volume may be created using an <code>encryption</code>
          element using "luks" format. This does require a previously created
          <code>secret</code> to store the passphrase used to encrypt the
          volume Adding the volume to a domain can then either provide the
          secret or allow the consumer in the guest to provide the passphrase
          in order to decrypt the volume.
        </description>
      </change>
      <change>
        <summary>
          net: Ignore auto-generated MAC address when detaching an interface
        </summary>
        <description>
          If the MAC address has not been specified by the user, libvirt will
          try and fill in the gaps by generating one; however, for some error
          paths that led to some confusing error messages, so when an
          auto-generated MAC address is specified the error message will not
          include the auto-generated MAC.
        </description>
      </change>
      <change>
        <summary>
          net: Enable MAC address lookup for virDomainInterfaceStats
        </summary>
      </change>
      <change>
        <summary>
          apparmor: Several improvements
        </summary>
        <description>
          Changes include permitting access to data about USB devices and
          <code>dnsmasq</code> instances, allowing spaces in guest names and
          many more.
        </description>
      </change>
      <change>
        <summary>
          cpu: Use CPU information obtained from QEMU when possible
        </summary>
        <description>
          Recent QEMU versions can expose information about which CPU models
          are available and usable on the host; libvirt will now make use of
          such information whenever possible.
        </description>
      </change>
      <change>
        <summary>
          hyperv: Various improvements
        </summary>
        <description>
          The error reported when clients can't connect to Hyper-V has been
          made more descriptive, and memory limits for guests are now mapped
          to more appropriate libvirt equivalents.
        </description>
      </change>
      <change>
        <summary>
          qemu: Report QEMU error on failed migration
        </summary>
        <description>
          Instead of reporting a generic error, ask QEMU for a more detailed
          and thus hopefully more helpful one.
        </description>
      </change>
      <change>
        <summary>
          vbox: Implement autoport for RDP
        </summary>
        <description>
          libvirt will now obtain the (dynamically allocated) RDP port number
          from VirtualBox itself, avoiding conflicts between multiple guests
          wanting to use RDP at the same time.
        </description>
      </change>
      <change>
        <summary>
          qemu: Allow rotation of small logs
        </summary>
        <description>
          On a host where numerous unique instances are executed per day, it's
          quite possible that, even though each of the single log files are
          fairly small, collectively the quantity and volume may add tens of
          thousands of log files to the <code>/var/log/libvirt/qemu/</code>
          directory. Removing the constraints that log have to be bigger than
          100 KiB before they can be rotated solves the issue.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          Fix swapped interface statistics and QoS
        </summary>
        <description>
          Due to internal implementation, reported statistics for
          some types of interfaces were swapped (RX appeared in
          TX and vice versa). Similarly, QoS was set in reversed
          way.
        </description>
      </change>
      <change>
        <summary>
          Properly resize local LUKS encrypted volume
        </summary>
        <description>
          Resizing of a local LUKS encrypted volume will now use qemu-img
          to resize the volume. This will require configuring a secret for
          the LUKS encrypted volume.
        </description>
      </change>
      <change>
        <summary>
          qemu: Reserve PCI addresses for implicit i440fx devices
        </summary>
        <description>
          Failing to do so causes the addresses to be considered usable by
          libvirt, which means they could be assigned to more than one device
          resulting in the guest failing to start.
        </description>
      </change>
      <change>
        <summary>
          spec: Restart libvirtd only at the end of the upgrade process
        </summary>
        <description>
          Use <code>%posttrans</code> to make sure <code>libvirtd</code>
          is not restarted before all other components, such as the library
          itself and storage / hypervisor drivers, have already been upgraded.
        </description>
      </change>
    </section>
    <section title="Security">
      <change>
        <summary>
          qemu: Ensure TLS clients always verify the server certificate
        </summary>
        <description>
          While it's reasonable to turn off client certificate validation,
          as setting it up can be non-trivial, clients should always verify
          the server certificate to avoid MITM attacks. However, libvirt was
          using the same knob to control both checks, leading to
          CVE-2017-1000256 / LSN-2017-0002.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.8.0" date="2017-10-04">
    <section title="New features">
      <change>
        <summary>
          qemu: Added support for cold-(un)plug of watchdog devices
        </summary>
      </change>
      <change>
        <summary>
          qemu: Added support for setting IP address os usernet interfaces
        </summary>
      </change>
      <change>
        <summary>
          qemu: Added support for Veritas Hyperscale (VxHS) block devices
        </summary>
      </change>
      <change>
        <summary>
          storage: Added new events for pool-build and pool-delete
        </summary>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: Set DAC permissions properly for spice rendernode
        </summary>
        <description>
          When a <code>rendernode</code> path is set for SPICE GL on
          <code>qemu:///system</code>, we now correctly set DAC permissions
          on the device at VM startup. This is the last remaining hurdle to
          let SPICE GL work for <code>qemu:///system</code> without any
          external host changes.
        </description>
      </change>
      <change>
        <summary>
          nodedev: Add switchdev offload query to NIC capabilities
        </summary>
        <description>
            Allow querying the NIC interface capabilities for the
            availability of switchdev offloading (also known as
            kernel-forward-plane-offload).
        </description>
      </change>
      <change>
        <summary>
          New CPU models for AMD and Intel
        </summary>
        <description>
          AMD EPYC and Intel Skylake-Server CPU models were added together with
          their features
        </description>
      </change>
      <change>
        <summary>
          Improve long waiting when saving a domain
        </summary>
        <description>
          While waiting for a write to disk to be finished, e.g. during save,
          even simple operations like <code>virsh list</code> would be blocking
          due to domain lock. This is now resolved by unlocking the domain
          in places where it is not needed.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          Proper units are now used in virsh manpage for dom(mem)stats
        </summary>
        <description>
          Previously the documentation used multiples of 1000, but now it is
          fixed to use multiples of 1024.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix error reporting when disk attachment fails
        </summary>
        <description>
          There was a possibility for the actual error to be overridden or
          cleared during the rollback.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix assignment of graphics ports after daemon restart
        </summary>
        <description>
          This could be seen with newer kernels that have bug regarding
          SO_REUSEADDR. After libvirtd was restarted it could assign already
          used address to new guests which would make them fail to start. This
          is fixed by marking used ports unavailable when reconnecting to
          running QEMU domains.
        </description>
      </change>
      <change>
        <summary>
          Fix message decoding which was causing a very strange bug
        </summary>
        <description>
          When parsing an RPC message with file descriptors was interrupted and
          had to restart, the offset of the payload was calculated badly causing
          strange issues like not being able to find a domain that was not
          requested.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.7.0" date="2017-09-04">
    <section title="New features">
      <change>
        <summary>
          qemu: Add managedsave-edit commands
        </summary>
        <description>
          Using managedsave-dumpxml, managedsave-define and managedsave-edit
          commands, now we can dump and edit the XML configuration of domain
          which has managedsave image.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add migrate-getmaxdowntime command
        </summary>
        <description>
          Currently, the maximum tolerable downtime for a domain being migrated
          is write-only from libvirt, via migrate-setmaxdowntime. This
          implements a complementary migrate-getmaxdowntime command
        </description>
      </change>
      <change>
        <summary>
          bhyve: Support autoport for VNC ports
        </summary>
        <description>
          It's no longer necessary to explicitly specify VNC port for the bhyve
          guests. With the autoport feature it will be allocated automatically.
          Please refer to the bhyve driver documentation for examples.
        </description>
      </change>
      <change>
        <summary>
          qemu: Added support for setting heads of virtio GPU
        </summary>
      </change>
      <change>
        <summary>
          qemu: Added support to configure reconnect timeout for chardev devices
        </summary>
        <description>
          When you have a TCP or UNIX chardev device and it's connected somewhere
          you can configure reconnect timeout if the connection is closed.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: Report a clear error when dropping a VM during startup
        </summary>
        <description>
          "Failed to load config for domain 'DOMNAME'" is now reported if a VM
          config can't be parsed for some reason, and thus provides a clear
          indication for users (and devs).
        </description>
      </change>
      <change>
        <summary>
          apparmor: Update for QEMU 2.10 compatibility
        </summary>
        <description>
          Starting with QEMU 2.10, disk images and NVRAM files get
          automatically locked to prevent them from being corrupted; however,
          file locking needs to be explicitly allowed through
          <code>virt-aa-helper</code> or AppArmor will reject the requests and
          the guest will not be able to run.
        </description>
      </change>
      <change>
        <summary>
          virsh: List Unix sockets in 'domdisplay' output
        </summary>
        <description>
          VNC and SPICE graphics can use Unix sockets instead of TCP/IP sockets
          as connection endpoints, but such a configuration was not handled
          correctly by <code>virsh domdisplay</code>, causing the respective
          endpoints to be missing from the output.
        </description>
      </change>
      <change>
        <summary>
          qemu: Don't check whether offline migration is safe
        </summary>
        <description>
          Since offline migration only copies the guest definition to the
          destination host, data corruption is not a concern and the operation
          can always be performed safely.
        </description>
      </change>
      <change>
        <summary>
          virt-host-validate: Fix IOMMU detection on ppc64
        </summary>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          qemu: Better support for international domain names (with wide characters)
        </summary>
        <description>
          There were some issues with multi-byte domains getting lost
          on daemon restart due to truncation, so the code now handles
          multi-byte names a bit better.
        </description>
      </change>
      <change>
        <summary>
          qemu: Support long domain names with namespaces
        </summary>
        <description>
          Domains with extremely long names would fail to start due to
          temporary namespace paths being created with the whole name.
          The path is now generated with shortened name instead.
        </description>
      </change>
      <change>
        <summary>
          qemu: Tolerate missing emulator binary during libvirtd restart
        </summary>
        <description>
          For some time libvirt required qemu capabilities being present when
          parsing VM configs during startup. As a side effect VM configs would
          fail to parse and thus vanish, if the emulator binary would be
          uninstalled or broken. Libvirt now tolerates when capabilities
          are missing during startup.
        </description>
      </change>
      <change>
        <summary>
          qemu: Prevent pSeries guests from disappearing in some situations
        </summary>
        <description>
          pSeries guest would disappear if any of the host devices they were
          configured to use was not available during libvirtd startup, which
          could easily happen for SR-IOV Virtual Functions. This scenario is
          now handled correctly.
        </description>
      </change>
      <change>
        <summary>
          qemu: Honor &lt;on_reboot/&gt; setting
        </summary>
        <description>
          The setting was accepted by the parser, but not actually implemented.
        </description>
      </change>
      <change>
        <summary>
          Fix --verbose option for all daemons
        </summary>
        <description>
          Since v3.0.0, the option had been ignored by all libvirt daemons
          (<code>libvirtd</code>, <code>virtlogd</code> and
          <code>virtlockd</code>); it's now working as intended once again.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.6.0" date="2017-08-02">
    <section title="New features">
      <change>
        <summary>
          hyperv: Implement virDomainSetMemory and virDomainSendKey APIs
        </summary>
      </change>
      <change>
        <summary>
          qemu: Support multiple PHBs for pSeries guests
        </summary>
        <description>
          pSeries guests can now have multiple PHBs (PCI Host Bridges), which
          show up as separate PCI domains in the guest. To create additional
          PHBs, simply add PCI controllers with model <code>pci-root</code>
          to the guest configuration.
        </description>
      </change>
      <change>
        <summary>
          qemu: Isolate hostdevs on pSeries guests
        </summary>
        <description>
          To enable better error reporting and recovery, unrelated hostdevs
          will now be automatically isolated on pSeries guests by placing them
          on separate PHBs (PCI Host Bridges).
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: platform serial devices can now use chardev features
        </summary>
        <description>
          QEMU VMs that depend on platform serial devices can now use
          QEMU's <code>-chardev</code> option, which enables access to
          advanced features like log file configuration. This applies
          to the default serial devices for arm, aarch64, and some ppc
          configurations.
        </description>
      </change>
      <change>
        <summary>
          Require use of GCC 4.4 or Clang compilers
        </summary>
        <description>
          We only ever test libvirt with GCC or Clang (which
          provides a GCC compatible compilation environment).
          Between them, these compilers cover every supported
          operating system platform, including Windows.
        </description>
      </change>
      <change>
        <summary>
          qemu: shared disks with directsync cache should be safe for migration
        </summary>
        <description>
          At present shared disks can be migrated with either readonly or
          <code>cache=none</code>. But <code>cache=directsync</code> should be
          safe for migration, because both <code>cache=directsync</code> and
          <code>cache=none</code> don't use the host page cache, and
          <code>cache=direct</code> write through qemu block layer cache.
        </description>
      </change>
      <change>
        <summary>
          Handle hotplug change on VLAN configuration using OVS
        </summary>
        <description>
          Libvirt was taught to handle VLAN change for running OVS interface.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          qemu: Use vCPU 'node-id' property and pass it back to qemu
        </summary>
        <description>
          vCPU properties gathered from query-hotpluggable-cpus need to be
          passed back to QEMU. As QEMU did not use the node-id property until
          now and libvirt forgot to pass it back properly (it was parsed but
          not passed around) we did not honor this.
        </description>
      </change>
      <change>
        <summary>
          Miscellaneous stream fixes
        </summary>
        <description>
          After introducing sparse stream features there were still some known
          bugs left. Those are fixed in this release.
        </description>
      </change>
      <change>
        <summary>
          qemu: Miscellaneous domain NS fixes
        </summary>
        <description>
          Libvirt starts qemu domains in separate Linux namespaces for a while
          now. However, there were still some bugs lingering. For instance
          libvirt did not know how to handle file based bind mounts.
        </description>
      </change>
      <change>
        <summary>
          Various CPU driver improvements
        </summary>
        <description>
          There were some minor bugs when using 'host-model' CPU.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.5.0" date="2017-07-04">
    <section title="New features">
      <change>
        <summary>
          qemu: Add support for loadparm for a boot device
        </summary>
        <description>
          Add an optional boot parameter 'loadparm' for a boot device.
          Loadparm is an 8 byte parameter that, when present, is queried by
          S390 guests via sclp or diag 308. Linux guests on S390 use it to
          select a boot entry.
        </description>
      </change>
      <change>
        <summary>
          Support controlling how video devices are exposed to the bhyve guests
        </summary>
        <description>
          The <code>vgaconf</code> attribute was added to <code>video</code>'s
          <code>driver</code> element. Possible values are: <code>on</code>,
          <code>off</code>, and <code>io</code>. It controls the way how
          bhyve exposes video devices to its guests; various guest OSes might
          require different settings to boot properly.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for live updates of coalesce settings
        </summary>
        <description>
          Users can now use <code>virsh update-device</code> to change
          the coalesce settings of an interfaces while the domain is
          running.
        </description>
      </change>
      <change>
        <summary>
          qemu: Allow VirtIO devices to use vIOMMU
        </summary>
        <description>
          It is now possible to turn on IOTBL for the vIOMMU and have VirtIO
          devices use it, provided they have been configured appropriately.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: block copy job can be used with persistent domains
        </summary>
        <description>
          Until now it was not possible to use block copy with persistent VMs.
          In use cases where it's not required to recover the job after VM
          shutdown, it's possible to specify VIR_DOMAIN_BLOCK_COPY_TRANSIENT_JOB
          flag to start the copy job.
        </description>
      </change>
      <change>
        <summary>
          JSON pseudo-protocol backing store parser supports new format of qemu 2.9
        </summary>
        <description>
          QEMU 2.9 modified a few structures corresponding to the JSON format
          of specifying a backing store for a disk image. Libvirt now implements
          the new format.
        </description>
      </change>
      <change>
        <summary>
          Capabilities now include info about host's CAT settings
        </summary>
        <description>
          Various information about resource control from the host is
          gathered and presented in capabilities if available.
        </description>
      </change>
      <change>
        <summary>
          apparmor: Several improvements
        </summary>
        <description>
          Allow access to Ceph config, EFI firmware on both x86_64 and
          aarch64, device tree on ppc64 and more.
        </description>
      </change>
      <change>
        <summary>
          qemu: Support host-model on POWER9 machines
        </summary>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          qemu: snapshot: retrieve image metadata from user provided files
        </summary>
        <description>
          Disk images of an external snapshot created with
          VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT flag specified would not be
          scanned for metadata after recent changes.

          The metadata is necessary to allow keeping relative paths between
          images when doing a block-commit.
        </description>
      </change>
      <change>
        <summary>
          Parse decimal numbers in a locale-independent way
        </summary>
        <description>
          Some locales, such as <code>de_DE</code> and <code>pt_BR</code>,
          use comma rather than dot to separate the integer part from the
          fractional part of a decimal number; however, several data sources
          such as the kernel use a locale-independent representation and need
          to be treated accordingly.
        </description>
      </change>
      <change>
        <summary>
          Support compilation with newer compiler and libc versions
        </summary>
        <description>
          Several fixes have been included to make compilation with Clang
          4.0.0, GCC 7.1 and glibc >= 2.25.90 possible.
        </description>
      </change>
      <change>
        <summary>
          qemu: Query name for vhost-user interfaces at runtime
        </summary>
        <description>
          This makes it possible to use <code>virsh</code> subcommands such
          as <code>domiflist</code> and <code>domifstat</code> on vhost-user
          interfaces.
        </description>
      </change>
      <change>
        <summary>
          qemu: Set MTU for hotplugged interfaces correctly
        </summary>
        <description>
          When hotplugging a network interface, the MTU was only set on the
          guest side. Set it on the host side as well.
        </description>
      </change>
      <change>
        <summary>
          qemu: Forbid updating MTU for interfaces of running guests
        </summary>
        <description>
          The MTU setting can't be modified while the guest is running, so any
          attempt to alter it at runtime will now result in an error rather
          than being silently ignored.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix specifying QXL heads with older QEMU releases
        </summary>
        <description>
          Specifying the number of QXL heads was not working correctly for
          QEMU releases older than 1.6.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix migration to older libvirt/QEMU versions
        </summary>
        <description>
          When the guest is started, libvirt updates the CPU definition to
          reflect the actual CPU features to enforce ABI. We need to send
          original and updated CPU definition in order to support migration
          to older libvirt/QEMU versions. Only the updated CPU definition
          was sent to destination.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.4.0" date="2017-06-02">
    <section title="New features">
      <change>
        <summary>
          Improved streams to efficiently transfer sparseness
        </summary>
        <description>
          New extension to virStream was implemented so that
          virStorageVolDownload and virStorageVolUpload can preserve file
          sparseness.
        </description>
      </change>
      <change>
        <summary>
          I/O APIC type can be specified for QEMU/KVM domains
        </summary>
        <description>
          The <code>ioapic</code> tag was added to domain
          <code>features</code>, so the type of the I/O APIC can now
          be specified (e.g. putting it in userspace for KVM domains).
        </description>
      </change>
      <change>
        <summary>
          The reason for VM shutdown is reported, if known
        </summary>
        <description>
          QEMU 2.10 will be able to report the reason for shutting
          down (whether that was caused by the guest or not), and
          libvirt is prepared for that and reports that information in
          its shutdown event as well, if it is known.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          Repository now has new README.md file
        </summary>
        <description>
          The new file uses markdown syntax, so it looks better on
          github and possibly other web pages, but it has also more
          useful information. The old README is now symlink to the
          new file.
        </description>
      </change>
      <change>
        <summary>
          qemu: Use GICv2 by default for aarch64/virt TCG guests
        </summary>
        <description>
          The emulated GICv3 has some limitations that make it unusable as a
          default; use GICv2 until they're sorted out. This change makes it
          once again possible to run aarch64/virt guests on a x86_64 host
          without having to tweak their configuration.
        </description>
      </change>
      <change>
        <summary>
          Additional capabilities for the node_device module
        </summary>
        <description>
          Introduce two new capabilities to the node_device module. The first
          is for CCW devices, most common on the S390 architecture. The second
          is for fibre channel-backed SCSI devices and exposes the
          fc_remote_port sub-capability to SCSI target devices.
        </description>
      </change>
      <change>
        <summary>
          Node devices now report Mediated device capabilities
        </summary>
        <description>
          Endpoint devices support new <code>mdev</code> capability
          and their parents now report the supported types in new
          <code>mdev_types</code> capability.
        </description>
      </change>
      <change>
        <summary>
          Capabilities now report information about host caches
        </summary>
        <description>
          If supported in the kernel, host capabilities will now list
          L3 caches. The code for other levels was added as well, but
          only L3 caches are reported currently.
        </description>
      </change>
      <change>
        <summary>
          POWER9 CPU model was added
        </summary>
        <description>
          It is now properly reported in host capabilities.
        </description>
      </change>
      <change>
        <summary>
          libxl: NUMA sibling distances are now reported in host capabilities
        </summary>
      </change>
      <change>
        <summary>
          VMDK version 3 files are now properly detected
        </summary>
      </change>
      <change>
        <summary>
          Interrupt remapping and Extended interrupt mode for IOMMU devices
        </summary>
        <description>
          These two new features can now be controlled with new
          <code>&lt;driver intremap='on/off' eim='on/off'/&gt;</code>
          tag for <code>iommu</code> devices.
        </description>
      </change>
      <change>
        <summary>
          Graphics in libxl domains now have default addresses
        </summary>
        <description>
          Even though there were default addresses before this change,
          they were not saved in the XML. It is now possible to see
          and control the listen addresses properly.
        </description>
      </change>
      <change>
        <summary>
          Default USB controllers are now added for devices in libxl domains
        </summary>
        <description>
          Even though they were added automatically when USB device
          was attached, they could've been missing in some other
          cases. The logic is now fixed so there are always USB
          controllers, even if there was none of them in the specified
          XML.
        </description>
      </change>
      <change>
        <summary>
          Limits for RPC messages were increased
        </summary>
        <description>
          Hitting the RPC limits we have is easier every day, so they
          were increased once again and some guessing logic was
          improved as well. It is now possible to get more stats than
          ever using the <code>virConnectGetAllDomainStats()</code>
          call and push through even bigger requests and replies for
          all APIs.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          qemu: Create memory_backing_dir on startup
        </summary>
        <description>
          Libvirt's policy is that directories are created on startup if
          they don't exist. We've missed this one.
        </description>
      </change>
      <change>
        <summary>
          PCIe 4.0 cards now report proper link speeds
        </summary>
        <description>
          It could happen that the link speed for PCIe devices was not
          properly reported or the nodedev-dumpxml just failed. That
          was due to mistake in the field width, but should now work
          properly.
        </description>
      </change>
      <change>
        <summary>
          qemu: Do not report errors on shutdown
        </summary>
        <description>
          For some users, in some rare cases, it could happen that
          there was an error message "internal error: End of file from
          qemu monitor" in the logs even though no problem happened.
          The detection of these false positives was improved and such
          errors should not show any more.
        </description>
      </change>
      <change>
        <summary>
          User-specified UNIX socket paths for virtio channels should not be reset
        </summary>
        <description>
          It could happen, in some cases, that libvirt would mistake a
          user-specified path for its own generated one and thus
          remove it from the XML. The detection of such addresses was
          improved now.
        </description>
      </change>
      <change>
        <summary>
          Fix address reservation during RNG hot-plug
        </summary>
        <description>
          When error occurred in a specific point in time during the
          hot-plug of an RNG device, it could happen that an address
          was released even though another device was already using
          it, making it possible to hot-plug another device with that
          address, effectively having duplicated addresses in the XML.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.3.0" date="2017-05-05">
    <section title="New features">
      <change>
        <summary>
          net: Add support for coalesce settings
        </summary>
        <description>
          Enabling data batching through these settings can improve network
          performance for guests.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for guest CPU cache specification
        </summary>
        <description>
          This features allows fine-grained control of the cache behavior
          of the guest CPU.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for the qemu-xhci USB controller
        </summary>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          hyperv: Support Hyper-V 2012 and newer
        </summary>
        <description>
          Starting with Hyper-V 2012 the API has changed causing the existing
          driver to be unable to send and process requests properly. This has
          been resolved by adding abstractions to handle the differences and
          ease handling such breaks if they happen in the future.
        </description>
      </change>
      <change>
        <summary>
          libxl: Add support for nested HVM domains
        </summary>
        <description>
          Xen has supported nested HVM domains since version 4.4. The
          libvirt libxl driver now supports nested HVM domains by
          specifying the host-passthrough CPU mode when defining a
          domain.
        </description>
      </change>
      <change>
        <summary>
          qemu: Implement ACPI support for aarch64 guests
        </summary>
        <description>
          Up until this point, ACPI support was only advertised for x86_64
          guests and disabling it for aarch64 guests was not possible at all.
        </description>
      </change>
      <change>
        <summary>
          vz: Add support for changing the number of vCPUs
        </summary>
      </change>
      <change>
        <summary>
          qemu: Automatically choose the best USB controller for guests
        </summary>
        <description>
          The recently introduced qemu-xhci USB controller is the best choice
          for both ppc64 and aarch64 guests, so use it by default on those
          architectures if available.
        </description>
      </change>
      <change>
        <summary>
          daemon: Increase default task limit for libvirtd
        </summary>
        <description>
          The default number of tasks for the pids cgroup controller is 512,
          which libvirtd can quickly bump into when starting lots of guests.
          Raise the limit to a more reasonable 32768.
        </description>
      </change>
      <change>
        <summary>
          docs: Include man pages describing key code names and values
        </summary>
      </change>
      <change>
        <summary>
          virsh: Report initialization errors
        </summary>
        <description>
          Sometimes virsh might be unable to start: when that happens, report
          useful diagnostics instead of failing silently.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          nss: Don't require a network restart for libvirt_guest
        </summary>
        <description>
          Previously, the libvirt_guest NSS module would only work properly
          after the corresponding network had been restarted; now newly
          started guests will be reported correctly right away.
        </description>
      </change>
      <change>
        <summary>
          storage: Remove unavailable transient pools after restart
        </summary>
        <description>
          Solve an issue where transient storage pools would be stuck in an
          unmanageable state if the source disappeared and libvirtd was
          subsequently restarted.
        </description>
      </change>
      <change>
        <summary>
          storage: Fix capacity value for LUKS encrypted volumes
        </summary>
        <description>
          The 'capacity' value (e.g. guest logical size) for a LUKS volume is
          smaller than the 'physical' value of the file in the file system, so
          we need to account for that.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix regression when hyperv/vendor_id feature is used
        </summary>
        <description>
          Guests using the feature would not be started at all; it is now
          possible to start them as expected.
        </description>
      </change>
      <change>
        <summary>
          qemu: Do not crash on USB address with no port and invalid bus
        </summary>
      </change>
      <change>
        <summary>
          crypto: Always pad data before encrypting it
        </summary>
        <description>
          If this step is not performed, when the data length matches the
          chunk size the decryption routines will misinterpret the last byte
          of data as the padding length and fail to decode it correctly.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.2.0" date="2017-04-02">
    <section title="New features">
      <change>
        <summary>
          The virt-host-validate tool now supports bhyve hypervisor
        </summary>
      </change>
      <change>
        <summary>
          Introduce NVDIMM memory model
        </summary>
        <description>
          NVDIMM is new type of memory introduced into QEMU 2.6. The idea is
          that we have a non-volatile memory module that keeps the data
          persistent across domain reboots and offers much faster data
          accesses. However, due to a bug in QEMU, this feature is not enabled
          for QEMUs older than 2.9.0.
        </description>
      </change>
      <change>
        <summary>
          qemu: Introduce support for generic PCIe Root Ports
        </summary>
        <description>
          For new controllers, a generic device (pcie-root-port) will be used
          by default instead of the Intel-specific device (ioh3420), provided
          the QEMU binary supports it.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for checking guest CPU ABI compatibility
        </summary>
        <description>
          When migrating a domain to a different host, restoring a domain from
          a file or reverting a snapshot libvirt will make sure the guest CPU
          QEMU presents to the guest OS exactly matches the one provided on
          the source host (or before the domain's state was saved). This
          enhanced check may also be requested when starting a new domain to
          ensure the virtual CPU exactly matches the one specified in the XML.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support to migrate using TLS
        </summary>
        <description>
          Add the ability to migrate QEMU guests using TLS via a new flag
          VIR_MIGRATE_TLS or virsh migrate '--tls' option. Requires using at
          least QEMU 2.9.0 in order to work properly.
        </description>
      </change>
      <change>
        <summary>
          qemu: add mediated devices framework support
        </summary>
        <description>
          Recent kernel version introduced new mediated device framework, so
          provide an initial support of this framework for libvirt, mainly by
          introducing a new host device type in the XML.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for setting TSC frequency
        </summary>
        <description>
          Setting TSC frequency is required to enable migration for domains
          with 'invtsc' CPU feature turned on.
        </description>
      </change>
      <change>
        <summary>
          Add support for block device threshold event
        </summary>
        <description>
          When using thin provisioning, management tools need to resize the
          disk in certain cases. To avoid having them to poll disk usage
          this version introduces an event which will be fired when a given
          offset of the storage is written by the hypervisor. Together with the
          API it allows registering thresholds for given storage backing
          volumes and this event will then notify management if the threshold
          is exceeded. Currently only the qemu driver supports this.
        </description>
      </change>
      <change>
        <summary>
           bhyve: Add support for UEFI boot ROM, VNC, and USB tablet
        </summary>
        <description>
          The bhyve driver now supports booting using the UEFI boot ROM,
          so non-FreeBSD guests that support UEFI could be booted without
          using an external boot loader like grub-bhyve. Video is also
          supported now, allowing to connect to guests via VNC and use
          an USB tablet as an input device. Please refer to
          the driver page for domain XML examples.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          qemu: Detect host CPU model by asking QEMU on x86_64
        </summary>
        <description>
          Previously, libvirt detected the host CPU model using CPUID
          instruction, which caused libvirt to detect a lot of CPU features
          that are not supported by QEMU/KVM. Asking QEMU makes sure we
          don't start it with unsupported features.
        </description>
      </change>
      <change>
        <summary>
          perf: Add more perf statistics
        </summary>
        <description>
          Add support to get the count of cpu clock time, task clock time,
          page faults, context switches, cpu migrations, minor page faults,
          major page faults, alignment faults, emulation faults by
          applications running on the platform.
        </description>
      </change>
      <change>
        <summary>
          Write hyperv crash information into vm log
        </summary>
        <description>
          qemu's implementation of the hyperv panic notifier now reports
          information about the crash from the guest os. Starting with this
          version, libvirt logs the information to the vm log file for possible
          debugging.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          QEMU: Use adaptive timeout for connecting to monitor
        </summary>
        <description>
          When starting qemu, libvirt waits for qemu to create the monitor
          socket which libvirt connects to. Historically, there was sharp 30
          second timeout after which the qemu process was killed. This
          approach is suboptimal as in some scenarios with huge amounts of
          guest RAM it can take a minute or more for kernel to allocate and
          zero out pages for qemu. The timeout is now flexible and computed by
          libvirt at domain startup.
        </description>
      </change>
      <change>
        <summary>
          Overwrite (clear) 2 KB instead of just 512 bytes when initializing logical device
        </summary>
      </change>
      <change>
        <summary>
          Describe the logical backend requirements better for pool-create-as
        </summary>
      </change>
    </section>
  </release>
  <release version="v3.1.0" date="2017-03-03">
    <section title="New features">
      <change>
        <summary>
          storage: Add Virtuozzo storage backend storage pool
        </summary>
        <description>
          Add new storage backend to support pool and volume management
          within the Virtuozzo Storage environment. Virtuozzo Storage is
          a highly available distributed software defined storage with
          built-in replication and disaster recovery.
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for memory backing with file source
        </summary>
        <description>
          Add support in numa topology for file source inside memory backing
          (hugepages are not needed) Three new elements
          &lt;source/&gt;,&lt;access/&gt; and &lt;allocation/&gt; were added
          to &lt;memoryBacking/&gt; element. Also new configuration parameter
          <code>memory_backing_dir</code> was added to qemu.conf.
        </description>
      </change>
      <change>
        <summary>
          network: make openvswitch call timeout configurable
        </summary>
        <description>
          Adding the ability to specify the timeout value in seconds for
          openvswitch calls in the libvirtd configuration file.
        </description>
      </change>
      <change>
        <summary>
          bhyve: add e1000 NIC support
        </summary>
        <description>
          Add support for e1000 NIC. Previously, the only available option
          was <code>virtio-net</code>.
        </description>
      </change>
      <change>
        <summary>
          libxl: add tunneled migration support
        </summary>
        <description>
          Add tunneled migration to libxl driver, which is always capable of
          strong encryption and doesn't require any extra network connection
          other than what's required for remote access of libvirtd.
        </description>
      </change>
      <change>
        <summary>
          qemu: add rendernode argument
        </summary>
        <description>
          Add a new attribute 'rendernode' to &lt;gl&gt; spice element.
        </description>
      </change>
      <change>
        <summary>
          nodedev: add drm capability
        </summary>
        <description>
          Add a new 'drm' capability for Direct Rendering Manager (DRM)
          devices, providing device type information.
        </description>
      </change>
      <change>
        <summary>
          Add API for individual/specific vCPU hotplug
        </summary>
        <description>
          The new API allows selecting specific vCPUs to be added/removed from
          the VM. The existing APIs allowed only adding/removing from the end
          which did not play well with NUMA.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
           virsh: pool-list: allow both --uuid and --name in one command
        </summary>
        <description>
          Adjust the virsh-pool command to support the --uuid and/or --name
          options in order to print just the --name and/or --uuid of pools.
        </description>
      </change>
      <change>
        <summary>
          Introduce MTU to domain &lt;interface/&gt; and &lt;network&gt;
        </summary>
        <description>
          Allow setting MTU size for some types of domain interface
          and network.
        </description>
      </change>
      <change>
        <summary>
          libxl: improve support for &lt;timer&gt; configurations
        </summary>
        <description>
          Add support for multiple timers. Extend the tsc timer to
          support the emulate mode. Improve conversion of timer XML
          to/from xl.cfg.
        </description>
      </change>
      <change>
        <summary>
          storage: modularize the storage driver
        </summary>
        <description>
          Split up the storage driver backends into loadable modules so that
          binary distributions don't have to compromise on shipping the storage
          driver with all backends which may pull in too many dependencies.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          nodedev: Fabric name must not be required for fc_host capability
        </summary>
        <description>
          fabric_name is one of many fc_host attributes in Linux that is
          optional and left to the low-level driver to decide if it is
          implemented. For example the zfcp device driver does not provide a
          fabric name for an fcp host. The requirement for the existence of
          a fabric name has been removed by making it optional.
        </description>
      </change>
      <change>
        <summary>
          bhyve: change address allocation schema for SATA disks
        </summary>
        <description>
          Previously, the bhyve driver assigned PCI addresses to SATA disks
          directly rather than assigning that to a controller and
          using SATA addresses for disks. It was implemented this way
          because bhyve has no notion of an explicit SATA controller.
          However, as this doesn't match libvirt's understanding of
          disk addresses, the bhyve driver was changed to follow
          the common schema and have PCI addresses for SATA controllers
          and SATA addresses for disks. If you're having issues
          because of this, it's recommended to edit the domain's XML
          and remove &lt;address type='pci'&gt; from the &lt;disk&gt;
          elements with &lt;target bus='sata'/&gt; and let libvirt
          regenerate it properly.
        </description>
      </change>
      <change>
        <summary>
          libxl: maximum memory fixes
        </summary>
        <description>
          Fix reporting of domain maximum memory. Fix setting dom0
          maximum memory.
        </description>
      </change>
      <change>
        <summary>
          libxl: fix disk detach when &lt;driver&gt; not specified
        </summary>
      </change>
      <change>
        <summary>
          libxl: fix dom0 autoballooning with Xen 4.8
        </summary>
      </change>
      <change>
        <summary>
          qemu: Allow empty script path to &lt;interface/&gt;
        </summary>
        <description>
          Historically, this was always allowed. Unfortunately, due to some
          rework done for 1.3.2 release a bug was dragged in which suddenly
          stop allowing domain with such configuration to start.
        </description>
      </change>
    </section>
  </release>
  <release version="v3.0.0" date="2017-01-17">
    <section title="New features">
      <change>
        <summary>
          Domain events for metadata content changes
        </summary>
        <description>
          The domain events framework has a new event ID that can
          be used to get notifications when domain metadata content
          changes.
        </description>
      </change>
      <change>
        <summary>
          Event notifications for the secret object
        </summary>
        <description>
          The secret object now supports event notifications, covering
          lifcycle changes and secret value changes.
        </description>
      </change>
      <change>
        <summary>
          New localPtr attribute for "ip" element in network XML
        </summary>
      </change>
      <change>
        <summary>
          qemu: Support QEMU group I/O throttling
        </summary>
        <description>
          Add the capability to allow group I/O throttling via a new
          domain &lt;disk&gt; &lt;iotune&gt; subelement "group_name"
          to allow sharing I/O throttling quota between multiple drives.
        </description>
      </change>
      <change>
        <summary>
          nss: Introduce libvirt_guest
        </summary>
        <description>
          New <code>libvirt_guest</code> nss module that translates libvirt
          guest names into IP addresses.
        </description>
      </change>
      <change>
        <summary>
          daemon: Add support for runtime logging settings adjustment
        </summary>
        <description>
          Logging-related settings like log outputs and filters can now be
          adjusted during runtime using the admin interface without the
          necessity of the daemon's restart.
        </description>
      </change>
      <change>
        <summary>
          storage: Add virStorageVolInfoFlags API
        </summary>
        <description>
          Add the API to support using the VIR_STORAGE_VOL_GET_PHYSICAL
          flag in order to return the host physical size in bytes
          of the image container in the allocation field of the
          _virStorageVolInfo structure. The --physical flag has been
          added to the virsh vol-info command to access the data.
        </description>
      </change>
      <change>
        <summary>
          libxl: Implement virDomainGetMaxVcpus API
        </summary>
      </change>
      <change>
        <summary>
          storage: Add overwrite flag checking for logical pool
        </summary>
        <description>
          Add support for the OVERWRITE flags for the logical storage
          backend including checking for existing data on the target
          volumes when building a new logical pool on target volume(s).
        </description>
      </change>
      <change>
        <summary>
          qemu: Add support for guest CPU configuration on s390(x)
        </summary>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          perf: Add more perf statistics
        </summary>
        <description>
          Add support to get the count of branch instructions
          executed, branch misses, bus cycles, stalled frontend
          cpu cycles, stalled backend cpu cycles, and ref cpu
          cycles by applications running on the platform.
        </description>
      </change>
      <change>
        <summary>
          conf: Display &lt;physical&gt; for volume xml
        </summary>
        <description>
          Add a display of the &lt;physical&gt; size of a disk
          volume in the output of the volume XML.
        </description>
      </change>
      <change>
        <summary>
          qemu: Use virtio-pci by default for aarch64 mach-virt guests
        </summary>
        <description>
          virtio-pci provides several advantages over virtio-mmio, such
          as the ability to hotplug devices and improved performance.
          While opting in to virtio-pci has been possible for a while,
          newly-defined guests will now use it automatically.
        </description>
      </change>
      <change>
        <summary>
          vbox: remove support for VirtualBox 3.x and older
        </summary>
        <description>
          Those old VirtualBox versions have been unsupported by
          upstream for a long time and the API of 4.0 and newer has
          diverged enough to require code abstractions to handle differences.
          Removing support for those old versions drops lots of code from
          the driver and simplifies the logic to ease implementation of new
          features going forward.
        </description>
      </change>
      <change>
        <summary>
          virsh: pool-info: introduce option --bytes
        </summary>
        <description>
          Add option --bytes to virsh pool-info in order ti allow display
          of units in bytes rather than default of human readable output.
        </description>
      </change>
      <change>
        <summary>
          scsi: Add parent wwnn/wwpn or fabric capability for createVport
        </summary>
        <description>
          Improve the algorithm searching for the parent scsi_host device
          for vHBA/NPIV scsi_host creation. Rather than supplying the
          "parent" by name, it's now possible to define the parent by
          it's wwnn/wwpn or fabric_wwn in the node device create XML or
          the storage pool XML.
        </description>
      </change>
      <change>
        <summary>
          qemu: aggregate pcie-root-ports onto multiple functions of a slot
        </summary>
        <description>
          When pcie-root-ports are added to pcie-root in order to
          provide a place to connect PCI Express endpoint devices,
          libvirt now aggregates multiple root ports together onto the
          same slot (up to 8 per slot) in order to conserve slots.
          Using this method, it's possible to connect more than 200
          endpoint devices to a guest that uses PCIe without requiring
          setup of any PCIe switches.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          lxc: fix accidental killing of containers during libvirtd restart
        </summary>
        <description>
          The libvirt_lxc process was previously not moved into the
          container scope. As a result, if systemd reloads its config
          after a container is started, when libvirtd is later restarted
          it will accidentally kill the containers.
        </description>
      </change>
      <change>
        <summary>
          qemu: Correct GetBlockInfo values
        </summary>
        <description>
          For an active domain, correct the physical value provided for
          a raw sparse file backed storage and the allocation value provided
          for a qcow2 file backed storage that hasn't yet been opened on
          the domain.
        </description>
      </change>
      <change>
        <summary>
          qemu: Make virtio console usable on ppc64 guests
        </summary>
        <description>
          The chardev detection code has been improved and can now handle this
          configuration properly.
        </description>
      </change>
      <change>
        <summary>
          qemu: Enable mount namespace
        </summary>
        <description>
          To avoid funny races with udev relabelling devices under our hands and
          to enhance security, libvirt now spawns each qemu process with its own
          <code>/dev</code>.
        </description>
      </change>
      <change>
        <summary>
          storage: Fix implementation of no-overwrite for file system backend
        </summary>
        <description>
          Fix file system storage backend implementation of the OVERWRITE
          flags to be consistent between code and documentation. Add checks
          to ensure that when building a new file system on a target volume
          that there is not something already on the disk in a format that
          libvirt can recognize.
        </description>
      </change>
      <change>
        <summary>
          qemu: Create hugepage path on per domain basis
        </summary>
        <description>
          Historically, all hugepage enabled domains shared the same path under
          hugetlbfs. This left libvirt unable to correctly set security labels
          on it. With this release, however, each domain is put into a
          separate path which is also correctly labeled.
        </description>
      </change>
      <change>
        <summary>
          conf: Reject domains with duplicate drive addresses
        </summary>
        <description>
          Reject duplicate drive addresses for disks and hostdevs at
          domain definition.
        </description>
      </change>
      <change>
        <summary>
          libxl: reverse defaults on HVM net device attach
        </summary>
        <description>
          Fixes network interface attach for HVM domains when no model is
          specified. Emulated hotplug isn't yet supported and hence we should
          default to the general working scenario.
        </description>
      </change>
      <change>
        <summary>
          libxl: always enable pae for x86_64 HVM
        </summary>
        <description>
          By default pae is disabled in libxl. Without an explicit &lt;pae/&gt;
          setting in the domain &lt;features&gt; configuration, an x86_64 HVM
          domain would be get an i686 environment. pae should always be enabled
          for x86_64 HVM domains.
        </description>
      </change>
      <change>
        <summary>
          qemu: Fix XML dump of autogenerated websocket
        </summary>
        <description>
          As a result autogenerated websocket port is regenerated on domain restore,
          migration and such as it should be.
        </description>
      </change>
    </section>
  </release>
  <release version="v2.5.0" date="2016-12-04">
    <section title="New features">
      <change>
        <summary>
          shmem: Add support for additional models
        </summary>
        <description>
          The shmem device can now utilize QEMU's ivshmem-plain and
          ivshmem-doorbell, more modern versions of ivshmem.
        </description>
      </change>
      <change>
        <summary>
          vbox: Add VirtualBox 5.1 support
        </summary>
      </change>
      <change>
        <summary>
          libssh: New transport
        </summary>
        <description>
          The new libssh transport allows one to connect to a running
          libvirtd via SSH, using the libssh library; for example:
          <code>qemu+libssh://server/system</code>.
        </description>
      </change>
      <change>
        <summary>
          vhost-scsi: Add support scsi_host hostdev passthrough
        </summary>
        <description>
          Add the capability to pass through a scsi_host HBA and the
          associated LUNs to the guest.
        </description>
      </change>
      <change>
        <summary>
          Allow debugging of gluster volumes in qemu
        </summary>
        <description>
          Users can now enable debug logging for native gluster
          volumes in qemu using the "gluster_debug_level" option in qemu.conf
        </description>
      </change>
      <change>
        <summary>
          Pre-allocate memory slots for memory hotplug
        </summary>
        <description>
          Slot numbers for memory devices are now automatically allocated and
          thus persistent. In addition slot numbers can be specified without
          providing a base address, which simplifies user configuration
        </description>
      </change>
      <change>
        <summary>
          qemu: Express devices will be placed on PCIe bus by default
        </summary>
        <description>
          For machine types that use a PCI Express root bus
          (e.g. x86_64/Q35 and aarch64/virt), any unaddressed PCI
          device that is an Express device (all virtio-1.0 devices,
          e1000e, nec-xhci, vfio assigned devices) will be placed on
          an Express controller (i.e. a pcie-root-port) instead of a
          legacy PCI controller (i.e. pci-bridge) with the root ports
          added as needed.
        </description>
      </change>
    </section>
    <section title="Improvements">
      <change>
        <summary>
          docs: Better documentation for migration APIs and flags
        </summary>
      </change>
      <change>
        <summary>
          vbox: Address thread safety issues
        </summary>
      </change>
      <change>
        <summary>
          virsh: Add support for passing an alternative persistent XML to migrate command
        </summary>
      </change>
      <change>
        <summary>
          vhostuser: Allow hotplug of multiqueue devices
        </summary>
      </change>
      <change>
        <summary>
          NEWS: Switch to an improved format
        </summary>
        <description>
          List user-visible changes instead of single commits for a better
          high-level overview of differences between libvirt releases.
        </description>
      </change>
      <change>
        <summary>
          website: Modernize layout and branding
        </summary>
        <description>
          The libvirt website looked very cluttered and outdated; it has now
          been completely overhauled, resulting in a design that's better
          organized and more pleasant to look at.
        </description>
      </change>
    </section>
    <section title="Bug fixes">
      <change>
        <summary>
          vz: Fix migration in P2P mode
        </summary>
      </change>
      <change>
        <summary>
          Forbid newline character in names of some libvirt objects
        </summary>
      </change>
      <change>
        <summary>
          Fix compilation on macOS
        </summary>
      </change>
    </section>
  </release>
</libvirt>