Release of libvirt-8.0.0
jdenemar at redhat.com
Fri Jan 14 14:20:25 UTC 2022
The 8.0.0 release of both libvirt and libvirt-python is tagged and
signed tarballs and source RPMs are available at
Thanks everybody who helped with this release by sending patches,
reviewing, testing, or providing feedback. Your work is greatly
* libxl: Fix potential deadlock and crash (CVE-2021-4147)
A rogue guest could continuously reboot itself and cause libvirtd on the
host to deadlock or crash, resulting in a denial of service condition.
* Removed features
* qemu: Explicitly forbid live changing nodeset for strict numatune
For ``strict`` mode of <numatune/> it can't be guaranteed that memory is
moved completely onto new set of nodes (e.g. QEMU might have locked pieces
of its memory) thus breaking the strict promise. If live migration of QEMU
memory between NUMA nodes is desired, users are advised to use
``restrictive`` mode instead.
* New features
* qemu: Synchronous write mode for disk copy operations
The ``blockdev-mirror`` block job supports a mode where writes from the VM
are synchronously propagated to the destination of the copy. This ensures
that the job will converge under heavy I/O.
Implement the mode for the copy blockjob as
``VIR_DOMAIN_BLOCK_COPY_SYNCHRONOUS_WRITES`` flag exposed via
``virsh blockcopy --synchronous-writes`` and for non-shared storage migration
as ``VIR_MIGRATE_NON_SHARED_SYNCHRONOUS_WRITES`` exposed via
``virsh migrate --copy-storage-synchronous-writes``.
* Introduce TCG domain features
Libvirt is now able to set the size of translation block cache size
(tb-size) for TCG domains.
* qemu: Add new API to inject a launch secret in a domain
New API ``virDomainSetLaunchSecurityState()`` and virsh command
``domsetlaunchsecstate`` are added to support injecting a launch secret
in a domain's memory.
* libxl: Implement the virDomainGetMessages API
* qemu: Preserve qcow2 sub-cluster allocation state after external snapshots and block-copy
The new image which is installed as an overlay on top of the current chain
when taking an external snapshot, or the target of a block copy operation
now enables sub-cluster allocation (``extended_l2``) if the original
image has the option enabled.
* Bug fixes
* qemu: Fix device hot-unplug with ``libvirt-7.9`` or ``libvirt-7.10`` used with ``qemu-6.2``
An internal change to the configuration format used by the above libvirt
versions triggers a bug in ``qemu-6.2`` where qemu no longer emits the
event notifying that the device was unplugged successfully and thus libvirt
never removes the device from the definition.
This impacts only devices which were present at startup of the VM, hotplugged
devices behave correctly.
This is fixed in ``libvirt-8.0`` by reverting to the old configuration
approach until qemu is fixed.
As a workaround for ``libvirt-7.9`` and ``libvirt-7.10`` the old configuration
approach can be forced by:
Option 1, global ``qemu.conf``::
capability_filters = [ "device.json" ]
Option 2, per VM XML override::
<domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
* Fix sparse streams with split daemon
In split daemon scenario, a client connected to a hypervisor driver and
using sparse streams (e.g. ``virsh vol-download --sparse``) would make the
hypervisor daemon enter an infinite loop without any data transfer. This is
* Build no longer requires RPC library
Code and its cross dependencies were fixed so that build without remote
driver and thus an RPC library (like ``tirpc``) fails no more.
* virnetdevopenvswitch: Fix 'burst' value passed to ovs-vsctl
When a ``<bandwidth/>`` was defined for a TAP device that's plugged into an
OvS bridge values passed to the OvS were incorrectly recalculated resulting
in slightly different limits being applied.
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