31b5ad06e3
This is a partial revert of 87a43a907f0ad4897a28ad7c216bc70f37270b93 The change to use g_clear_pointer() in more places was accidentally applied to cases involving vir_g_source_unref(). In some cases, the ordering of g_source_destroy() and vir_g_source_unref() was reversed, which resulted in the source being marked as destroyed, after it is already unreferenced. This use-after-free case might work in many cases, but with versions of glib older than 2.64.0 it may defer unref to run within the main thread to avoid a race condition, which creates a large distance between the g_source_unref() and g_source_destroy(). In some cases, the call to vir_g_source_unref() was replaced with a second call to g_source_destroy(), leading to a memory leak or worse. In our experience, the symptoms were that use of libvirt-python became slower over time, with OpenStack nova-compute initially taking around one second to periodically query the host PCI devices, and within an hour it was taking over a minute to complete the same operation, until it is was eventually running this query back-to-back, resulting in the nova-compute process consuming 100% of one CPU thread, losing its RabbitMQ connection frequently, and showing up as down to the control plane. Signed-off-by: Mark Mielke <mark.mielke@gmail.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Signed-off-by: Ján Tomko <jtomko@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: