7e0a310498
For backward compatibility with older versions of libvirt CPU models in our CPU map are mostly immutable. We only changed them in a few specific cases after showing it was safe. Sometimes QEMU developers realize a specific feature should not be part of a particular (or any) CPU model because it can never be enabled automatically without further configuration. But we couldn't follow them because doing so would break migration to older libvirt. If QEMU drops feature F from CPU model M because F could not be enabled automatically anyway, asking for M would never enable F. Even with older QEMU versions. Naively removing F from libvirt's definition of M would seem to work nicely on a single host. Libvirt would consider M to be compatible with hosts CPU that do not support F. However, trying to migrate domains using M without explicitly enabling or disabling F could fail, because older libvirt would think F was enabled (it is part of M there), but QEMU reports it as disabled once started. Thus we can remove such feature from a libvirt's CPU model, but we have to make sure any CPU definition using the affected model will always explicitly mention the state of the removed feature. https://bugzilla.redhat.com/show_bug.cgi?id=1798004 Signed-off-by: Jiri Denemark <jdenemar@redhat.com> Reviewed-by: Tim Wiederhake <twiederh@redhat.com>
Libvirt API for virtualization
Libvirt provides a portable, long term stable C API for managing the virtualization technologies provided by many operating systems. It includes support for QEMU, KVM, Xen, LXC, bhyve, Virtuozzo, VMware vCenter and ESX, VMware Desktop, Hyper-V, VirtualBox and the POWER Hypervisor.
For some of these hypervisors, it provides a stateful management daemon which runs on the virtualization host allowing access to the API both by non-privileged local users and remote users.
Layered packages provide bindings of the libvirt C API into other languages including Python, Perl, PHP, Go, Java, OCaml, as well as mappings into object systems such as GObject, CIM and SNMP.
Further information about the libvirt project can be found on the website:
License
The libvirt C API is distributed under the terms of GNU Lesser General Public License, version 2.1 (or later). Some parts of the code that are not part of the C library may have the more restrictive GNU General Public License, version 2.0 (or later). See the files COPYING.LESSER and COPYING for full license terms & conditions.
Installation
Instructions on building and installing libvirt can be found on the website:
https://libvirt.org/compiling.html
Contributing
The libvirt project welcomes contributions in many ways. For most components the best way to contribute is to send patches to the primary development mailing list. Further guidance on this can be found on the website:
https://libvirt.org/contribute.html
Contact
The libvirt project has two primary mailing lists:
- libvirt-users@redhat.com (for user discussions)
- libvir-list@redhat.com (for development only)
Further details on contacting the project are available on the website: