January 2025 - Devel - libvirt List Archives

Release of libvirt-11.0.0
by Jiri Denemark 15 Jan '25

15 Jan '25

The 11.0.0 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. * New features * network/qemu/lxc: support vlans on standard Linux host bridges The network, qemu, and lxc drivers now support (using the ``<vlan>`` subelement) vlan tagging and trunking on network interfaces connected to a standard Linux host bridge. * qemu: Add support for direct and extended tlbflush features Domains can now utilise more tlbflush hyperv features. * Improvements * ch: Enable user aliases User can now specify custom aliases for devices in domain XML * qemu: Grab a QUERY job when formatting domain XML Under some specific conditions it might have happened that domain XML did not contain runtime information or returned an XML that's in process of changing (e.g. by a thread that's hotplugging a device). Formatting domain XML now serializes properly with other threads. * virtiofs: Allow read only mode The ``<filesystem/>`` with `virtiofsd` backend can now use ``<readonly/>`` tag to export underlying filesystem in read only mode. * qemu: allow migration of vGPU from mdev device <-> SRIOV VF device Some GPU vendors are switching from using vGPUs creating using mdev and identified with a uuid, to vGPUs created as SRIOV VFs and identified by their PCI address, and want to support live migration from a host using one type of vGPU to the other type. This is now possible. * Bug fixes * qemu: tpm: do not update profile name for transient domains Fix a possible crash when starting a transient domain which was introduced in the previous release. * qemu: Fix snapshot to not delete disk image with internal snapshot When a VM has internal snapshot that is parent to external snapshot and user reverts to the internal snapshot and deletes the external snapshot libvirt would delete the disk image containing the internal snapshot. This would result in data loss. * qemu: Do not format invalid XML with hyperv features in passthrough mode When hyperv features were specified together with ``mode="passthrough"`` libvirt parsed and formatted such features in the domain XML even though they were not used at all, resulting in XML that is not valid based on our schema. This is now fixed by not parsing any specified features when the passthrough mode is used. * qemu: Fix a crash when starting a domain with ovs bridge and QOS * cpu: Add missing -v1 variants for CPU models Some CPU models (mostly old ones) were missed when versioned CPU model names were introduced in the previous release. * qemu: Fix false error when recovering failed post-copy migration In some cases libvirt would report a failure to recover post-copy migration even though the recovery started just fine and migration would eventually successfully finish. Enjoy. Jirka

1 0

[PATCH 00/20] qemu: support mapped-ram+directio+mulitfd
by Jim Fehlig 14 Jan '25

14 Jan '25

This series is essentially V1 of a prior RFC [1] to support QEMU's mapped-ram stream format [2] and migration capability. Along with supporting mapped-ram, it implements a design approach we discussed for supporting parallel save/restore [3]. In summary, the approach is 1. Add mapped-ram migration capability 2. Steal an element from save header 'unused' for a 'features' variable and bump save version to 3. 3. Add /etc/libvirt/qemu.conf knob for the save format version, defaulting to latest v3 4. Use v3 (aka mapped-ram) by default 5. Use mapped-ram with BYPASS_CACHE for v3, old approach for v2 6. include: Define constants for parallel save/restore 7. qemu: Add support for parallel save. Implies mapped-ram, reject if v2 8. qemu: Add support for parallel restore. Implies mapped-ram. Reject if v2 9. tools: add parallel parameter to virsh save command 10. tools: add parallel parameter to virsh restore command With this series, saving and restoring using mapped-ram is enabled by default if the underlying QEMU advertises the mapped-ram migration capability. It can be disabled by changing the 'save_image_version' setting in qemu.conf. To use mapped-ram with QEMU: - The 'mapped-ram' migration capability must be set to true - The 'multifd' migration capability must be set to true and the 'multifd-channels' migration parameter must set to a value >= 1 - QEMU must be provided an fdset containing the migration fd(s) - The 'migrate' qmp command is invoked with a URI referencing the fdset and an offset where to start reading or writing the data stream, e.g. {"execute":"migrate", "arguments":{"detach":true,"resume":false, "uri":"file:/dev/fdset/0,offset=0x11921"}} The mapped-ram stream, in conjunction with direct IO and multifd, can significantly improve the time required to save VM memory state. The following tables compare mapped-ram with the existing, sequential save stream. In all cases, the save and restore operations are to/from a block device comprised of two NVMe disks in RAID0 configuration with xfs (~8600MiB/s). The values in the 'save time' and 'restore time' columns were scraped from the 'real' time reported by time(1). The 'Size' and 'Blocks' columns were provided by the corresponding outputs of stat(1). VM: 32G RAM, 1 vcpu, idle (shortly after boot) | save | restore | | time | time | Size | Blocks -----------------------+---------+---------+--------------+-------- legacy | 6.193s | 4.399s | 985744812 | 1925288 -----------------------+---------+---------+--------------+-------- mapped-ram | 5.109s | 1.176s | 34368554354 | 1774472 -----------------------+---------+---------+--------------+-------- legacy + direct IO | 5.725s | 4.512s | 985765251 | 1925328 -----------------------+---------+---------+--------------+-------- mapped-ram + direct IO | 4.627s | 1.490s | 34368554354 | 1774304 -----------------------+---------+---------+--------------+-------- mapped-ram + direct IO | | | | + multifd-channels=8 | 4.421s | 0.845s | 34368554318 | 1774312 ------------------------------------------------------------------- VM: 32G RAM, 30G dirty, 1 vcpu in tight loop dirtying memory | save | restore | | time | time | Size | Blocks -----------------------+---------+---------+--------------+--------- legacy | 25.800s | 14.332s | 33154309983 | 64754512 -----------------------+---------+---------+--------------+--------- mapped-ram | 18.742s | 15.027s | 34368559228 | 64617160 -----------------------+---------+---------+--------------+--------- legacy + direct IO | 13.115s | 18.050s | 33154310496 | 64754520 -----------------------+---------+---------+--------------+--------- mapped-ram + direct IO | 13.623s | 15.959s | 34368557392 | 64662040 -----------------------+-------- +---------+--------------+--------- mapped-ram + direct IO | | | | + multifd-channels=8 | 6.994s | 6.470s | 34368554980 | 64665776 -------------------------------------------------------------------- As can be seen from the tables, one caveat of mapped-ram is the logical file size of a saved image is basically equivalent to the VM memory size. Note however that mapped-ram typically uses fewer blocks on disk. Support for mapped-ram+direct-io only recently landed in upstream QEMU and will first appear in the 9.1 release, which may complicate merging support in libvirt. Specifically, I'm not sure how to detect if the combination is supported by QEMU. Suggestions welcomed. Similar to the RFC, V1 ignores compression. libvirt currently supports compression by connecting the output of QEMU's save stream to the specified compression program via a pipe. This approach is incompatible with mapped-ram since the fd provided to QEMU must be seekable. In general, we can consider mapped-ram and compression incompatible and document they cannot be used together. [1] https://lists.libvirt.org/archives/list/devel@lists.libvirt.org/message/EF6… [2] https://gitlab.com/qemu-project/qemu/-/blob/master/docs/devel/migration/map… [3] https://lists.libvirt.org/archives/list/devel@lists.libvirt.org/message/K4B… Claudio Fontana (2): include: Define constants for parallel save/restore tools: add parallel parameter to virsh restore command Jim Fehlig (17): lib: virDomainSaveParams: Ensure absolute save path qemu_fd: Add function to retrieve fdset ID qemu: Add function to check capability in migration params qemu: Add function to get bool value from migration params qemu: Add mapped-ram migration capability qemu: Add function to get migration params for save qemu: QEMU_SAVE_VERSION: Bump to version 3 qemu: conf: Add setting for save image version qemu: Add helper function for creating save image fd qemu: Add support for mapped-ram on save qemu: Decompose qemuSaveImageOpen qemu: Move creation of qemuProcessIncomingDef struct qemu: Apply migration parameters in qemuMigrationDstRun qemu: Add support for mapped-ram on restore qemu: Support O_DIRECT with mapped-ram on save qemu: Support O_DIRECT with mapped-ram on restore qemu: Add support for parallel save and restore Li Zhang (1): tools: add parallel parameter to virsh save command docs/manpages/virsh.rst | 9 +- include/libvirt/libvirt-domain.h | 13 ++ src/libvirt-domain.c | 52 +++++-- src/qemu/libvirtd_qemu.aug | 1 + src/qemu/qemu.conf.in | 6 + src/qemu/qemu_conf.c | 16 +++ src/qemu/qemu_conf.h | 5 + src/qemu/qemu_driver.c | 104 +++++++++----- src/qemu/qemu_fd.c | 18 +++ src/qemu/qemu_fd.h | 3 + src/qemu/qemu_migration.c | 192 +++++++++++++++++-------- src/qemu/qemu_migration.h | 9 +- src/qemu/qemu_migration_params.c | 86 ++++++++++++ src/qemu/qemu_migration_params.h | 17 +++ src/qemu/qemu_monitor.c | 39 ++++++ src/qemu/qemu_monitor.h | 5 + src/qemu/qemu_process.c | 120 +++++++++++----- src/qemu/qemu_process.h | 19 ++- src/qemu/qemu_saveimage.c | 216 ++++++++++++++++++++--------- src/qemu/qemu_saveimage.h | 35 +++-- src/qemu/qemu_snapshot.c | 26 ++-- src/qemu/test_libvirtd_qemu.aug.in | 1 + tools/virsh-domain.c | 79 +++++++++-- 23 files changed, 827 insertions(+), 244 deletions(-) -- 2.35.3

4 47

[PATCH] NEWS: Document some of my fixes in this release
by Jiri Denemark 14 Jan '25

14 Jan '25

Signed-off-by: Jiri Denemark <jdenemar(a)redhat.com> --- NEWS.rst | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/NEWS.rst b/NEWS.rst index 15042595ed..1d3e3c3cff 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -61,6 +61,19 @@ v11.0.0 (unreleased) schema. This is now fixed by not parsing any specified features when the passthrough mode is used. + * qemu: Fix a crash when starting a domain with ovs bridge and QOS + + * cpu: Add missing -v1 variants for CPU models + + Some CPU models (mostly old ones) were missed when versioned CPU model + names were introduced in the previous release. + + * qemu: Fix false error when recovering failed post-copy migration + + In some cases libvirt would report a failure to recover post-copy migration + even though the recovery started just fine and migration would eventually + successfully finish. + v10.10.0 (2024-12-02) ===================== -- 2.47.1

2 1

[PATCH] NEWS: Add few things I changed this release
by Martin Kletzander 14 Jan '25

14 Jan '25

Signed-off-by: Martin Kletzander <mkletzan(a)redhat.com> --- NEWS.rst | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/NEWS.rst b/NEWS.rst index 9f0804ec67ff..02679602cc6a 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -17,6 +17,10 @@ v11.0.0 (unreleased) * **New features** + * qemu: Add support for direct and extended tlbflush features + + Domains can now utilise more tlbflush hyperv features. + * **Improvements** * ch: Enable user aliases @@ -42,6 +46,14 @@ v11.0.0 (unreleased) Fix a possible crash when starting a transient domain which was introduced in the previous release. + * qemu: Do not format invalid XML with hyperv features in passthrough mode + + When hyperv features were specified together with ``mode="passthrough"`` + libvirt parsed and formatted such features in the domain XML even though + they were not used at all, resulting in XML that is not valid based on our + schema. This is now fixed by not parsing any specified features when the + passthrough mode is used. + v10.10.0 (2024-12-02) ===================== -- 2.48.0

2 1

[PATCH] NEWS: Document features/improvements/bug fixes I've participated in
by Michal Privoznik 14 Jan '25

14 Jan '25

There are some features/improvements/bug fixes I've either contributed or reviewed/merged. Document them for upcoming release. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com> --- NEWS.rst | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/NEWS.rst b/NEWS.rst index eedb6008bd..9f0804ec67 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -19,6 +19,22 @@ v11.0.0 (unreleased) * **Improvements** + * ch: Enable user aliases + + User can now specify custom aliases for devices in domain XML + + * qemu: Grab a QUERY job when formatting domain XML + + Under some specific conditions it might have happened that domain XML did + not contain runtime information or returned an XML that's in process of + changing (e.g. by a thread that's hotplugging a device). Formatting domain + XML now serializes properly with other threads. + + * virtiofs: Allow read only mode + + The ``<filesystem/>`` with `virtiofsd` backend can now use ``<readonly/>`` + tag to export underlying filesystem in read only mode. + * **Bug fixes** * qemu: tpm: do not update profile name for transient domains -- 2.45.2

2 1

[libvirt PATCH] NEWS: document bug fix for snapshots
by Pavel Hrdina 14 Jan '25

14 Jan '25

Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com> --- NEWS.rst | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/NEWS.rst b/NEWS.rst index 08d1d24d48..98f489dfb0 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -21,6 +21,13 @@ v11.0.0 (unreleased) * **Bug fixes** + * qemu: Fix snapshot to not delete disk image with internal snapshot + + When a VM has internal snapshot that is parent to external snapshot and user + reverts to the internal snapshot and deletes the external snapshot Libvirt + would delete the disk image containing the internal snapshot. This would result + in data loss. + v10.10.0 (2024-12-02) ===================== -- 2.47.1

2 1

[libvirt PATCH] NEWS: document fix for starting transient domains
by Ján Tomko 14 Jan '25

14 Jan '25

Signed-off-by: Ján Tomko <jtomko(a)redhat.com> --- NEWS.rst | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/NEWS.rst b/NEWS.rst index 08d1d24d48..eedb6008bd 100644 --- a/NEWS.rst +++ b/NEWS.rst @@ -21,6 +21,11 @@ v11.0.0 (unreleased) * **Bug fixes** + * qemu: tpm: do not update profile name for transient domains + + Fix a possible crash when starting a transient domain which was + introduced in the previous release. + v10.10.0 (2024-12-02) ===================== -- 2.47.0

2 1

Entering freeze for libvirt-11.0.0
by Jiri Denemark 13 Jan '25

13 Jan '25

I have just tagged v11.0.0-rc1 in the repository and pushed signed tarballs to https://download.libvirt.org/ Please give the release candidate some testing and in case you find a serious issue which should have a fix in the upcoming release, feel free to reply to this thread to make sure the issue is more visible. If you have not done so yet, please update NEWS.rst to document any significant change you made since the last release. Thanks, Jirka

1 1

[PATCH 0/2] storage_file: Refuse qcow2 images with empty string as 'data_file'
by Peter Krempa 13 Jan '25

13 Jan '25

See patch 1/2 for justification. Patch 2 is a test case. Peter Krempa (2): storage_file: Refuse qcow2 images with empty string as 'data_file' virstoragetest: Add case for qcow2 image with empty string as 'data_file' src/storage_file/storage_source.c | 10 ++++++++++ tests/virstoragetest.c | 5 +++++ .../images/datafile-emptystr.qcow2 | Bin 0 -> 327680 bytes 3 files changed, 15 insertions(+) create mode 100644 tests/virstoragetestdata/images/datafile-emptystr.qcow2 -- 2.47.1

2 3

[PATCH] meson: Replace meson.source_root() with meson.project_source_root()
by Michal Privoznik 13 Jan '25

13 Jan '25

The source_root() method is deprecated in 0.56.0 and we're recommended to use project_source_root() instead. This is similar to commit v8.9.0-rc1~70 but somehow, the old method sneaked in. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com> --- meson.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/meson.build b/meson.build index c1a2e6eadb..f8eff99e2c 100644 --- a/meson.build +++ b/meson.build @@ -17,7 +17,7 @@ endif i18n = import('i18n') -po_dir = meson.source_root() / 'po' +po_dir = meson.project_source_root() / 'po' # figure out if we are building from git -- 2.45.2

2 1