dbf1f68410
Files inside /dev/vfio/ can't be opened more than once, meaning that any subsequent open calls will fail. This behavior was introduced in kernel v3.11, commit 6d6768c61b39. When using the VFIO driver, we open a FD to /dev/vfio/N and pass it to QEMU. If any other call attempt for the same /dev/vfio/N happens while QEMU is still using the file, we are unable to open it and QEMU will report -EBUSY. This can happen if we hotplug a PCI hostdev that belongs to the same IOMMU group of an existing domain hostdev. The problem and solution is similar to what we already dealt with for TPM in commit 4e95cdcbb3. This patch changes both DAC and SELinux drivers to disable 'remember' for VFIO hostdevs in virSecurityDACSetHostdevLabelHelper() and virSecurityDACSetHostdevLabel(), and 'recall' in virSecurityDACRestoreHostdevLabel() and virSecuritySELinuxRestoreHostdevSubsysLabel(). Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com> Reviewed-by: Michal Privoznik <mprivozn@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
Libvirt uses the GNU Autotools build system, so in general can be built and installed with the usual commands, however, we mandate to have the build directory different than the source directory. For example, to build in a manner that is suitable for installing as root, use:
$ mkdir build && cd build
$ ../configure --prefix=/usr --sysconfdir=/etc --localstatedir=/var
$ make
$ sudo make install
While to build & install as an unprivileged user
$ mkdir build && cd build
$ ../configure --prefix=$HOME/usr
$ make
$ make install
The libvirt code relies on a large number of 3rd party libraries. These will
be detected during execution of the configure script and a summary printed
which lists any missing (optional) dependencies.
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: