379c0ce4bf
Our code relies on mount events propagating into the namespace we create for a domain. However, there's one caveat. In v8.8.0-rc1~8 I've tried to make us detect differences in mount tables between the namespace in which libvirtd runs and the domain namespace. This is crucial for any mounts that happen after the domain was started (for instance new hugetlbfs can be mounted on say /dev/hugepages1G). Therefore, we take a look into /proc/$(pgrep qemu)/mounts to see what filesystems are mounted under /dev. Now, since we don't umount the original /dev, just mount a tmpfs over it, we get all the events (e.g. aforementioned hugetlbfs mount on /dev/hugepages1G), but we are not really able to access it because of the tmpfs that's placed on top. This then confuses our algorithm for detecting which filesystems are mounted (the algorithm is implemented in qemuDomainGetPreservedMounts()). To break the link between host's and guest's /dev we just need to umount() the original /dev in the namespace. Just before our artificially created tmpfs is moved into its place. Fixes: 46b03819ae8d833b11c2aaccb2c2a0361727f51b Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2151869#c6 Signed-off-by: Michal Privoznik <mprivozn@redhat.com> Reviewed-by: Martin Kletzander <mkletzan@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: