December 2025 - Devel - libvirt List Archives

[RFC v3 0/5] cover: RFE libvirt secret encryption on disk
by Arun Menon 02 Dec '25

02 Dec '25

Libvirt secrets are stored unencrypted on the disk. With this series we want to start encrypting the secrets. 1. Introduce the GnuTLS decryption wrapper functions that work exact opposite to the encryption wrappers. 2. Add a new service called virt-secrets-init-encryption, that is linked to the virtsecretd service. virtsecretd service only starts after the new service generates a random encryption key. 3. Add a new secrets.conf configuration file that helps user to set a. secrets_encryption_key - allows the user to specify the encryption key file path, in case the default key is not to be used. b. encrypt_data - set to 0 or 1. If set to 1, then the newly added secrets will be encrypted. 4. Add encryption scheme or cipher attribute that will allow us to choose the last used cipher. 5. Once we have the encryption key, and a reliable way to tell the daemon what encryption scheme the secret object is using, we can encrypt the secrets on disk and store them in <uuid>.<encryption_scheme> format. It is important to note that if the encryption key is changed between restarts, then the respective secret will not be loaded by the driver. This is a sincere attempt to improve upon the already submitted patch https://lists.libvirt.org/archives/list/devel@lists.libvirt.org/thread/KE6G… Resolves: https://issues.redhat.com/browse/RHEL-7125 --- Changes in v3: - Secrets xml configuration no longer stores the encryption scheme, therefore not allowing the user to toggle between ciphers. - Removed unnecessary socket files of the new service. It now has a general configuration with which it starts. - Addressed review comments from Peter on coding style and design. - Loading of secrets is dependent on the file extension. Most recent cipher is used while saving the secrets. Changes in v2: - Corrected the encryption key length check. It should be 32. - Added a new patch that introduces the encryption scheme attribute. This will help us identify which secrets are encrypted. - A new systemd unit service file added that starts before virtsecretd, helping us to construct a random encryption key and pass it to the virtsecretd service. - Parsing logic of secrets.conf moved to a separate file. - Spec file changes, augeas. Arun Menon (5): util: Add support for GnuTLS decryption secret: Set up default encryption secret key for the virtsecretd service secret: Add secrets.conf configuration file and parse it secret: Add encryptionSchemeType attribute to store ciphers secret: Add functionality to load and save secrets in encrypted format include/libvirt/libvirt-secret.h | 20 +++ libvirt.spec.in | 7 + po/POTFILES | 1 + src/conf/meson.build | 1 + src/conf/secret_conf.h | 1 + src/conf/secret_config.c | 177 ++++++++++++++++++++++++ src/conf/secret_config.h | 38 +++++ src/conf/virsecretobj.c | 177 ++++++++++++++++++------ src/conf/virsecretobj.h | 13 +- src/libvirt_private.syms | 3 + src/meson.build | 1 + src/secret/libvirt_secrets.aug | 40 ++++++ src/secret/meson.build | 42 ++++++ src/secret/secret-init-encryption.in | 10 ++ src/secret/secret_driver.c | 27 +++- src/secret/secrets.conf.in | 12 ++ src/secret/test_libvirt_secrets.aug.in | 6 + src/secret/virtsecretd.service.extra.in | 8 ++ src/util/vircrypto.c | 126 ++++++++++++++++- src/util/vircrypto.h | 8 ++ src/util/virsecret.c | 4 + src/util/virsecret.h | 1 + tests/vircryptotest.c | 65 +++++++++ 23 files changed, 735 insertions(+), 53 deletions(-) create mode 100644 src/conf/secret_config.c create mode 100644 src/conf/secret_config.h create mode 100644 src/secret/libvirt_secrets.aug create mode 100644 src/secret/secret-init-encryption.in create mode 100644 src/secret/secrets.conf.in create mode 100644 src/secret/test_libvirt_secrets.aug.in -- 2.51.1

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[PATCH 0/8] Avoid changing const string via strchr() and friends
by Michal Privoznik 02 Dec '25

02 Dec '25

This stems from the discussion here: https://lists.libvirt.org/archives/list/devel@lists.libvirt.org/thread/HVMC… Green pipeline here: https://gitlab.com/MichalPrivoznik/libvirt/-/pipelines/2183169334 Michal Prívozník (8): vircommand: Update documentation to virCommandSetDryRun() virstringtest: Introduce a test for virSkipSpacesBackwards() virfirewalltest: Introduce testIPtablesSetupPrivateChains() virSkipSpacesBackwards: Turn @endp into const iptablesPrivateChainCreate: Rename @tmp variable iptablesPrivateChainCreate: Switch to STRSKIP() iptablesPrivateChainCreate: Avoid modifying const string lib: Avoid changing const strings via strchr() and friends src/interface/interface_backend_udev.c | 2 +- src/libxl/xen_common.c | 10 +- src/libxl/xen_xm.c | 10 +- src/network/meson.build | 1 + src/network/network_iptables.c | 33 ++++--- src/node_device/node_device_udev.c | 2 +- src/nwfilter/nwfilter_ebiptables_driver.c | 4 +- src/qemu/qemu_monitor_json.c | 2 +- src/qemu/qemu_nbdkit.c | 2 +- src/rpc/virnetsshsession.c | 5 +- src/storage/storage_util.c | 2 +- src/storage_file/storage_source.c | 4 +- src/util/vircgroup.c | 2 +- src/util/vircommand.c | 10 +- src/util/virfile.c | 2 +- src/util/virstoragefile.c | 4 +- src/util/virstring.c | 20 ++-- src/util/virstring.h | 2 +- src/util/virsysinfo.c | 22 ++--- src/util/virxml.c | 3 +- src/vmware/vmware_conf.c | 2 +- tests/meson.build | 9 +- tests/virfirewalltest.c | 111 ++++++++++++++++++++++ tests/virstringtest.c | 48 ++++++++++ tools/vsh.c | 6 +- 25 files changed, 252 insertions(+), 66 deletions(-) -- 2.51.2

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[RFC PATCH v3 0/4] qemu: Implement support for EGM
by Nathan Chen 01 Dec '25

01 Dec '25

The Grace SOC introduces Extended GPU Memory (EGM) [3], a feature that enables GPUs to efficiently access system memory within and across nodes. This patch series adds support for virtualizing EGM (vEGM) in libvirt, allowing VMs to utilize dedicated EGM memory regions through ACPI. This patch series is a follow-up RFC to the second EGM RFC series [0], to gather feedback from the libvirt community on the overall approach and implementation details. While kernel EGM driver support and QEMU acpi-egm-memory device support are not yet upstream, reference implementations are available [1][2] to enable testing and validation of the libvirt integration. Any community feedback is appreciated. Background and Use Cases ========================= EGM allows host memory to be partitioned into two regions: 1. Standard memory for Host OS usage 2. EGM region assigned to VMs as their system memory This technology enables various high-performance computing scenarios [3]: - Large memory pools for AI/ML workloads - High-performance computing applications - Memory extension for systems with limited main memory - GPU-accelerated workloads requiring large addressable memory Implementation Overview ======================= This series adds a new memory device model VIR_DOMAIN_MEMORY_MODEL_EGM with 'path' source attribute and 'pciDev' target attribute to denote host EGM device backing path and PCI device alias to associate the vEGM with, respectively. For instance, given the XML stanzas below: <memory model='egm' access='shared'> <source> <path>/dev/egm4</path> </source> <target> <size unit='KiB'>8388608</size> <node>0</node> <pciDev>ua-hostdev0</pciDev> </target> </memory> <memory model='egm' access='shared'> <source> <path>/dev/egm5</path> </source> <target> <size unit='KiB'>8388608</size> <node>1</node> <pciDev>ua-hostdev1</pciDev> </target> </memory> The corresponding qemu command line will include the following arguments: -object '{"qom-type":"memory-backend-file","id":"memegm0","mem-path":"/dev/egm4","share":true,"prealloc":true,"size":8589934592}' \ -object acpi-egm-memory,id=egm0,pci-dev=ua-hostdev0,node=0 \ -object '{"qom-type":"memory-backend-file","id":"memegm1","mem-path":"/dev/egm5","share":true,"prealloc":true,"size":8589934592}' \ -object acpi-egm-memory,id=egm1,pci-dev=ua-hostdev1,node=1 \ -numa node,nodeid=0,cpus=0-1,memdev=memegm4 \ -numa node,nodeid=1,cpus=2-3,memdev=memegm5 \ For a system where multiple GPUs are associated with a single host socket/NUMA node/EGM chardev, we consolidate the memory backing into a single memory-backend-file object per host EGM chardev. For instance, given the XML stanzas below: <memory model='egm' access='shared'> <source> <path>/dev/egm4</path> </source> <target> <size unit='KiB'>8388608</size> <node>0</node> <pciDev>ua-hostdev0</pciDev> </target> </memory> <memory model='egm' access='shared'> <source> <path>/dev/egm4</path> </source> <target> <size unit='KiB'>8388608</size> <node>0</node> <pciDev>ua-hostdev1</pciDev> </target> </memory> The corresponding qemu command line will include the following arguments: -object '{"qom-type":"memory-backend-file","id":"memegm0","mem-path":"/dev/egm4","share":true,"prealloc":true,"size":17179869184}' \ -object acpi-egm-memory,id=egm0,pci-dev=ua-hostdev0,node=0 \ -object acpi-egm-memory,id=egm1,pci-dev=ua-hostdev1,node=0 \ -numa node,nodeid=0,cpus=0-4,memdev=memegm0 \ Changes from RFCv2: - Decouple host EGM chardev name from guest EGM ID - Consolidate all acpi-egm-memory objects' memory into a single memory-backend-file per EGM chardev specified. Changes from RFCv1: - Use existing memory device infrastructure to represent EGM configuration - Added support for multiple EGM devices This series is on Github: https://github.com/NathanChenNVIDIA/libvirt/tree/egm-11-24-25 Thanks, Nathan [0] https://lists.libvirt.org/archives/list/devel@lists.libvirt.org/thread/6RU7… [1] https://github.com/ianm-nv/qemu/tree/6.8_ghvirt_egm_may2025 [2] https://github.com/NVIDIA/QEMU/commit/32db1b74fb99c0571724c7e69485e89098c14… [3] https://developer.nvidia.com/blog/nvidia-grace-hopper-superchip-architectur… Ian May (1): tests: Add qemuxmlconftest for ACPI EGM memory device Nathan Chen (3): conf: Support EGM memory device model qemu: Add cgroup, namespace, and seclabel setup for EGM memory device model qemu: Add qemu CLI support for EGM docs/formatdomain.rst | 18 +- src/conf/domain_conf.c | 34 +++- src/conf/domain_conf.h | 7 + src/conf/domain_postparse.c | 6 +- src/conf/domain_validate.c | 15 ++ src/conf/schemas/domaincommon.rng | 6 + src/qemu/qemu_alias.c | 7 +- src/qemu/qemu_capabilities.c | 2 + src/qemu/qemu_capabilities.h | 1 + src/qemu/qemu_cgroup.c | 10 ++ src/qemu/qemu_command.c | 158 ++++++++++++++++-- src/qemu/qemu_domain.c | 15 +- src/qemu/qemu_domain_address.c | 3 + src/qemu/qemu_driver.c | 1 + src/qemu/qemu_hotplug.c | 1 + src/qemu/qemu_monitor_json.c | 1 + src/qemu/qemu_namespace.c | 3 + src/qemu/qemu_postparse.c | 1 + src/qemu/qemu_process.c | 2 + src/qemu/qemu_validate.c | 6 + src/security/apparmor/usr.sbin.libvirtd.in | 3 + src/security/security_apparmor.c | 2 + src/security/security_dac.c | 8 + src/security/security_selinux.c | 6 + src/security/virt-aa-helper.c | 4 + src/util/virfile.h | 2 +- tests/meson.build | 1 + tests/qemuegmmock.c | 67 ++++++++ .../acpi-egm-memory.aarch64-latest.args | 47 ++++++ .../acpi-egm-memory.aarch64-latest.xml | 124 ++++++++++++++ tests/qemuxmlconfdata/acpi-egm-memory.xml | 124 ++++++++++++++ tests/qemuxmlconftest.c | 8 +- 32 files changed, 672 insertions(+), 21 deletions(-) create mode 100644 tests/qemuegmmock.c create mode 100644 tests/qemuxmlconfdata/acpi-egm-memory.aarch64-latest.args create mode 100644 tests/qemuxmlconfdata/acpi-egm-memory.aarch64-latest.xml create mode 100644 tests/qemuxmlconfdata/acpi-egm-memory.xml -- 2.43.0

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[PATCH 0/3] Fix VMX-* feature detection from MSR
by Hector Cao 01 Dec '25

01 Dec '25

Currently, libvirt is unable to detect the CPU model of recent Intel CPUs (like Granite Rapids) with VMX-* features specified in the MSRs (Model Specific Registers). This is due to the wrong parsing of these VMX-* features from the MSR values. This series of 3 commits allow to fix the MSR VMX-* feature detection. This has been tested successfully on a platform equipped with Intel Granite Rapids CPU. Hector Cao (3): cpu_map: fix sync script to extract correctly vmx-* features cpu_map: update vmx-* features cputest : fix test failures due to VMX-* feature update src/cpu_map/sync_qemu_features_i386.py | 19 +++ src/cpu_map/x86_features.xml | 136 +++++++++--------- .../x86_64-cpuid-Atom-P5362-2-enabled.xml | 10 +- .../x86_64-cpuid-Atom-P5362-enabled.xml | 10 +- .../x86_64-cpuid-Cooperlake-enabled.xml | 10 +- .../x86_64-cpuid-Core-i7-1270P-enabled.xml | 10 +- .../x86_64-cpuid-Core-i7-1365U-enabled.xml | 10 +- .../x86_64-cpuid-Core-i7-8550U-enabled.xml | 10 +- .../x86_64-cpuid-Xeon-6731E-enabled.xml | 10 +- .../x86_64-cpuid-Xeon-6788P-disabled.xml | 1 + .../x86_64-cpuid-Xeon-6788P-enabled.xml | 10 +- .../x86_64-cpuid-Xeon-6788P-guest.xml | 17 ++- .../x86_64-cpuid-Xeon-6788P-host.xml | 17 ++- ...x86_64-cpuid-Xeon-Bronze-3408U-enabled.xml | 10 +- .../x86_64-cpuid-Xeon-E3-1270-v5-enabled.xml | 10 +- .../x86_64-cpuid-Xeon-Gold-6152-enabled.xml | 10 +- .../x86_64-cpuid-Xeon-Gold-6530-enabled.xml | 10 +- ...86_64-cpuid-Xeon-Platinum-9242-enabled.xml | 10 +- ...x86_64-cpuid-Xeon-Silver-4214R-enabled.xml | 10 +- .../x86_64-cpuid-Xeon-w7-3465X-enabled.xml | 10 +- 20 files changed, 181 insertions(+), 159 deletions(-) -- 2.45.2

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[PATCH] spec: Fix RPM build when %{fedora} is undefined
by Jiri Denemark 01 Dec '25

01 Dec '25

From: Jiri Denemark <jdenemar(a)redhat.com> Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com> --- Pushed as trivial build breaker. libvirt.spec.in | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/libvirt.spec.in b/libvirt.spec.in index 8b3bc9884f..ccfe75135b 100644 --- a/libvirt.spec.in +++ b/libvirt.spec.in @@ -41,7 +41,7 @@ %define with_qemu 0%{!?_without_qemu:1} %else # QEMU drops 32-bit in Fedora 44 - %if %{?fedora} > 43 + %if 0%{?fedora} > 43 %define with_qemu 0 %else %define with_qemu 0%{!?_without_qemu:1} -- 2.51.1

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Release of libvirt-11.10.0
by Jiri Denemark 01 Dec '25

01 Dec '25

The 11.10.0 release of both libvirt and libvirt-python is tagged and signed tarballs are available at https://download.libvirt.org/ https://download.libvirt.org/python/ Thanks everybody who helped with this release by sending patches, reviewing, testing, or providing feedback. Your work is greatly appreciated. * Security * CVE-2025-12748: Denial of service by some ACL-limited accounts Parsing of user provided XMLs in APIs which needed the identification information from those XML definitions was done in full before ACL checks were performed. Some valid, but useless, definitions could cause allocation of too much memory, leading to denial of service. APIs which do equate to full root access (such as ``domain:write``), and were parsing XML definitions in full before performing ACL checks could, potentially, be exploited in a way that would allow users (which were about to be denied the API call) to cause aforementioned overallocation even before the ACL checks were performed. A change was made so that parsing before ACL checks are done only for the identification parts of the XML definition (which is needed to perform the checks) and full parsing is done only after checking all ACLs. * CVE-2025-13193: Incorrect permissions on images after external snapshot of an inactive VM The overlay ``qcow2`` images which are created as part of creation of an external snapshot of an inactive VM had world-readable (644) permissions which would allow unauthorized users to see contents of blocks written by the VM after snapshot was taken. Libvirt now sets proper umask so that the images are created with 600 mode. * New features * Hyper-V virttype support for Qemu domains Libvirt now supports Hyper-V virttype while lauching QEMU domains. This feature requires Qemu version 10.2.0 or later and is available on Linux hosts where the /dev/mshv is present. * Add more statistics for block devices on QEMU domains The block devices now report optimal access request sizes as well as statistics such as the queue depth. * Improvements * bhyve: VNC ``wait`` attribute support Bhyve guests can now be configured to wait for a VNC connection before booting. * remote: multiple certificate support The remote daemon and client can be configured to load multiple x509 certificate identities. This facilitates a transition to certificates supporting Post-Quantum Crytographic algorithms. * tools: improved virt-host-validate output The virt-host-validate tool will now report extra details when certain checks pass. * qemu: Allow backup jobs to continue if guest OS shuts down When starting a backup job users can now use a flag which prevents the VM to be completely cleaned up if the guest OS shuts down while the backup is running so that the backup can be finalized. * Bug fixes * ch: Use correct domain definition in chDomainGetXMLDesc() Cloud-Hypervisor driver claims to support ``VIR_DOMAIN_XML_INACTIVE`` but in fact it never formatted the inactive XML. This is now fixed. * esx: Allow disk images in subdirectories If a domain has a disk image that's not in a datastore path but in a subdirectory, the ESX driver would have failed to parse that and an error was reported when obtaining domain XML. This is now fixed. * qemu: Fix incoming migration to QEMU 10.0.0 and newer Due to a change in the way QEMU 10.0.0 reports the state of "ht" CPU feature, incoming migration of a domain with multiple CPU threads would fail with "guest CPU doesn't match specification: extra features: ht" error. * qemu: fix incorrect reporting of the TDX launch security type The TDX launch security type was incorrectly reported on all platforms if the QEMU binary had it built-in. It is now limited to only platforms with the TDX kernel feature available for use. * qemu: set ``detect_zeroes`` for all backing chain layers Some block jobs (snapshots, block commit) could modify the backing chain in a way where ``detect_zeroes`` would no longer be honoured. We now set it for all images in the backing chain, so that it will behave correctly even after those operations. Enjoy. Jirka

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