December 2025 - Devel - libvirt List Archives

[libvirt] [PATCH 00/23] Fix host-model if the chosen CPU model has more features in QEMU compared to our cpu_map.xml
by Jiri Denemark 15 Oct '26

15 Oct '26

When decoding CPUID data to virCPUDef we need to be careful about using a CPU model which cannot be directly used on the current host. Normally, libvirt would notice the features which prevent the model from being usable and it would disable them in the computed virCPUDef, but this won't work in case the definition of the CPU model in QEMU contains more features than what we have in cpu_map.xml. We need to count with the usability blockers we got from QEMU and explicitly disable all of them to make the computed virCPUDef usable. https://bugzilla.redhat.com/show_bug.cgi?id=1464832 Jiri Denemark (23): util: Introduce virStringListCopy conf: Add usability blockers to virDomainCapsCPUModel qemu: Store CPU usability blockers in caps cache qemu: Parse unavailable features for CPU models cpu: Use virDomainCapsCPUModelsPtr in cpu driver APIs cpu: Drop unused parameter from cpuDecode cpu: Return model from virCPUModelIsAllowed cpu_x86: Move x86FeatureFind* to avoid forward prototypes cpu_x86: Disable blockers from unusable CPU models cputest: Replace json bool with enum cputest: Avoid calling json_reformat in cpu-parse.sh cputest: Print correct feature in virCPUUpdateLive test cputest: Test CPU usability blockers cputest: Separate QEMUCaps creation from cpuTestCPUIDJson build: Export virCPUModelIsAllowed private API cputest: Use CPU models from QEMU when available cputest: Add query-cpu-definitions reply for Core-i5-2540M cputest: Add CPUID data for Intel(R) Xeon(R) CPU E7-4830 cputest: Add query-cpu-definitions reply for Xeon-E7-4830 cputest: Update Xeon-E3-1245 data cputest: Add query-cpu-definitions reply for Xeon-E3-1245 cputest: Update Core-i7-2600 data cputest: Make a crippled version of Core-i7-2600 src/conf/domain_capabilities.c | 30 +- src/conf/domain_capabilities.h | 7 +- src/cpu/cpu.c | 95 +- src/cpu/cpu.h | 31 +- src/cpu/cpu_arm.c | 3 +- src/cpu/cpu_ppc64.c | 14 +- src/cpu/cpu_x86.c | 108 +- src/libvirt_private.syms | 1 + src/libxl/libxl_capabilities.c | 2 +- src/libxl/libxl_driver.c | 2 +- src/qemu/qemu_capabilities.c | 123 +-- src/qemu/qemu_capabilities.h | 6 +- src/qemu/qemu_capspriv.h | 5 + src/qemu/qemu_driver.c | 2 +- src/qemu/qemu_monitor.c | 2 + src/qemu/qemu_monitor.h | 1 + src/qemu/qemu_monitor_json.c | 26 +- src/qemu/qemu_process.c | 9 +- src/test/test_driver.c | 2 +- src/util/virstring.c | 37 + src/util/virstring.h | 3 + tests/cputest.c | 324 ++++-- tests/cputestdata/cpu-cpuid.py | 26 +- tests/cputestdata/cpu-gather.sh | 1 + tests/cputestdata/cpu-parse.sh | 2 +- tests/cputestdata/cpu-reformat.py | 9 + tests/cputestdata/x86_64-cpuid-Core-i5-2540M.json | 362 +++++++ .../x86_64-cpuid-Core-i7-2600-disabled.xml | 1 - .../x86_64-cpuid-Core-i7-2600-enabled.xml | 1 + .../cputestdata/x86_64-cpuid-Core-i7-2600-json.xml | 1 + ...x86_64-cpuid-Core-i7-2600-xsaveopt-disabled.xml | 6 + .../x86_64-cpuid-Core-i7-2600-xsaveopt-enabled.xml | 8 + .../x86_64-cpuid-Core-i7-2600-xsaveopt-guest.xml | 25 + .../x86_64-cpuid-Core-i7-2600-xsaveopt-host.xml | 25 + .../x86_64-cpuid-Core-i7-2600-xsaveopt-json.xml | 11 + .../x86_64-cpuid-Core-i7-2600-xsaveopt.json | 615 +++++++++++ .../x86_64-cpuid-Core-i7-2600-xsaveopt.xml | 33 + tests/cputestdata/x86_64-cpuid-Core-i7-2600.json | 496 ++++++++- tests/cputestdata/x86_64-cpuid-Core-i7-2600.xml | 6 +- .../x86_64-cpuid-Xeon-E3-1245-disabled.xml | 1 - .../x86_64-cpuid-Xeon-E3-1245-enabled.xml | 2 +- .../cputestdata/x86_64-cpuid-Xeon-E3-1245-json.xml | 1 + tests/cputestdata/x86_64-cpuid-Xeon-E3-1245.json | 712 +++++++++---- tests/cputestdata/x86_64-cpuid-Xeon-E3-1245.xml | 7 +- .../x86_64-cpuid-Xeon-E7-4830-disabled.xml | 5 + .../x86_64-cpuid-Xeon-E7-4830-enabled.xml | 8 + .../x86_64-cpuid-Xeon-E7-4830-guest.xml | 28 + .../cputestdata/x86_64-cpuid-Xeon-E7-4830-host.xml | 29 + .../cputestdata/x86_64-cpuid-Xeon-E7-4830-json.xml | 14 + tests/cputestdata/x86_64-cpuid-Xeon-E7-4830.json | 657 ++++++++++++ tests/cputestdata/x86_64-cpuid-Xeon-E7-4830.xml | 30 + tests/domaincapstest.c | 6 +- tests/qemucapabilitiesdata/caps_2.10.0.s390x.xml | 1102 ++++++++++++++++++-- tests/qemucapabilitiesdata/caps_2.10.0.x86_64.xml | 236 ++++- tests/qemucapabilitiesdata/caps_2.8.0.x86_64.xml | 154 ++- tests/qemucapabilitiesdata/caps_2.9.0.x86_64.xml | 154 ++- 56 files changed, 4927 insertions(+), 680 deletions(-) create mode 100755 tests/cputestdata/cpu-reformat.py create mode 100644 tests/cputestdata/x86_64-cpuid-Core-i7-2600-xsaveopt-disabled.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Core-i7-2600-xsaveopt-enabled.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Core-i7-2600-xsaveopt-guest.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Core-i7-2600-xsaveopt-host.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Core-i7-2600-xsaveopt-json.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Core-i7-2600-xsaveopt.json create mode 100644 tests/cputestdata/x86_64-cpuid-Core-i7-2600-xsaveopt.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Xeon-E7-4830-disabled.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Xeon-E7-4830-enabled.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Xeon-E7-4830-guest.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Xeon-E7-4830-host.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Xeon-E7-4830-json.xml create mode 100644 tests/cputestdata/x86_64-cpuid-Xeon-E7-4830.json create mode 100644 tests/cputestdata/x86_64-cpuid-Xeon-E7-4830.xml -- 2.14.2

3 66

[PULL 00/32] Next pr patches
by Daniel P. Berrangé 23 Apr '26

23 Apr '26

The following changes since commit 53b41bb78950912ba2d9809eef6b45e4df30c647: Merge tag 'pull-target-arm-20251031' of https://gitlab.com/pm215/qemu into staging (2025-11-01 10:52:48 +0100) are available in the Git repository at: https://gitlab.com/berrange/qemu tags/next-pr-pull-request for you to fetch changes up to 2aaca8c6d22b18786ceff51189704113d0639590: docs: creation of x509 certs compliant with post-quantum crypto (2025-11-03 10:45:55 +0000) ---------------------------------------------------------------- Merge crypto and other misc fixes / features * Increase minimum gnutls to 3.7.5 * Increase minimum libgcrypt to 1.9.4 * Increase minimum nettle to 3.7.3 * Drop obsolete in-tree XTS impl * Fix memory leak when loading certificates * Remove/reduce duplication when loading certifcates * Fix possible crash when certificates are unloaded while an active TLS connection is using when in a TLS handshake operation * Deprecate use of dh-params.pem file * Document how to create certificates with Post-Quantum Cryptography compliant algorithms. * Support loading multiple certificate identities to allow support for Post-Quantum crypto in parallel with traditional RSA/ECC * Add "-run-with exit-with-parent=on" parameter * Flush pending errors when seeing ENOBUFS with a zero-copy send attempt * Fix data buffer parameters in hash & IO channel APIs to use 'void *' ---------------------------------------------------------------- Daniel P. Berrangé (26): crypto: bump min gnutls to 3.7.5 crypto: unconditionally enable gnutls XTS support crypto: bump min libgcrypt to 1.9.4 crypto: bump min nettle to 3.7.3 crypto: drop in-tree XTS cipher mode impl crypto: remove redundant parameter checking CA certs crypto: add missing free of certs array crypto: replace stat() with access() for credential checks crypto: remove redundant access() checks before loading certs crypto: move check for TLS creds 'dir' property crypto: use g_autofree when loading x509 credentials crypto: remove needless indirection via parent_obj field crypto: move release of DH parameters into TLS creds parent crypto: shorten the endpoint == server check in TLS creds crypto: remove duplication loading x509 CA cert crypto: reduce duplication in handling TLS priority strings crypto: introduce method for reloading TLS creds crypto: introduce a wrapper around gnutls credentials crypto: fix lifecycle handling of gnutls credentials objects crypto: make TLS credentials structs private crypto: deprecate use of external dh-params.pem file crypto: avoid loading the CA certs twice crypto: avoid loading the identity certs twice crypto: expand logic to cope with multiple certificate identities crypto: support upto 5 parallel certificate identities docs: creation of x509 certs compliant with post-quantum crypto Manish Mishra (1): io: flush zerocopy socket error queue on sendmsg failure due to ENOBUF Philippe Mathieu-Daudé (2): crypto/hash: Have hashing functions take void * buffer argument io/channel: Have read/write functions take void * buffer argument Richard W.M. Jones (2): Implement -run-with exit-with-parent=on tests/qtest: Use exit-with-parent=on in qtest invocations Tejus GK (1): io: add a "blocking" field to QIOChannelSocket crypto/cipher-gnutls.c.inc | 8 - crypto/cipher-nettle.c.inc | 44 -- crypto/cipher.c | 2 +- crypto/hash.c | 16 +- crypto/hmac.c | 8 +- crypto/meson.build | 10 +- crypto/tlscreds.c | 79 ++-- crypto/tlscredsanon.c | 64 +-- crypto/tlscredsbox.c | 101 +++++ crypto/tlscredsbox.h | 50 +++ crypto/tlscredspriv.h | 36 +- crypto/tlscredspsk.c | 64 ++- crypto/tlscredsx509.c | 593 +++++++++++++++++--------- crypto/tlssession.c | 139 ++---- crypto/trace-events | 1 + crypto/xts.c | 250 ----------- docs/about/deprecated.rst | 9 + docs/system/tls.rst | 134 +++++- include/crypto/hash.h | 8 +- include/crypto/hmac.h | 4 +- include/crypto/tlscreds.h | 26 ++ include/crypto/tlscredsx509.h | 6 + include/crypto/tlssession.h | 4 +- include/crypto/xts.h | 82 ---- include/io/channel-socket.h | 6 + include/io/channel.h | 14 +- include/qemu/exit-with-parent.h | 57 +++ io/channel-socket.c | 86 +++- io/channel-tls.c | 4 +- io/channel.c | 14 +- meson.build | 69 +-- qemu-options.hx | 13 +- system/exit-with-parent.c | 140 ++++++ system/meson.build | 1 + system/vl.c | 13 + tests/qtest/libqtest.c | 22 +- tests/unit/meson.build | 3 - tests/unit/test-crypto-block.c | 3 +- tests/unit/test-crypto-tlscredsx509.c | 8 +- tests/unit/test-crypto-tlssession.c | 4 +- tests/unit/test-crypto-xts.c | 529 ----------------------- ui/vnc.c | 9 +- 42 files changed, 1208 insertions(+), 1525 deletions(-) create mode 100644 crypto/tlscredsbox.c create mode 100644 crypto/tlscredsbox.h delete mode 100644 crypto/xts.c delete mode 100644 include/crypto/xts.h create mode 100644 include/qemu/exit-with-parent.h create mode 100644 system/exit-with-parent.c delete mode 100644 tests/unit/test-crypto-xts.c -- 2.51.1

3 36

Re: Clarification Needed: virsh snapshot-delete Behavior with External Snapshots (--disk-only)
by Peter Krempa 10 Apr '26

10 Apr '26

On Wed, Jul 23, 2025 at 04:57:57 +0000, P, Rajasekar via Users wrote: > Hello libvirt community, > > I am seeking clarification on the behavior of `virsh snapshot-delete` when used with external snapshots (created with the `--disk-only` option). > > **Environment:** > - libvirt version: 10.5.0 Note that this was released almost a year ago. > - Kernel version: 5.14.0-503.22.1.el9_5.x86_64 > - Disk image format: qcow2 > - Host OS: RHEL 9.5 > > **Steps to reproduce:** > 1. Create an external snapshot: > virsh snapshot-create-as --domain <vm> --name snap1 --disk-only --atomic > 2. Delete the snapshot: > virsh snapshot-delete <vm> --snapshotname snap1 > > **Observed behavior:** > - Changes from the overlay (snapshot) file are merged into the base image. > - The snapshot metadata is removed from libvirt. > - The snapshot file remains on disk (appears orphaned). You mean that the original overlay images remained on disk? e.g. /path/to/originalimage.snap1 ? > **Questions:** > - Is the observed automatic merge of the overlay file into the base image during `snapshot-delete` the intended behavior for external snapshots in recent libvirt versions? Or we need separate `blockcommit` step. Yes it is intended, because deleting a snapshot is effectively meaning "I don't want to return to this point any more" so the extra overlay makes no sense. > - Should the snapshot file be deleted automatically, or is manual cleanup required? If you mean the overlay, then yes it should have been deleted. > - Is there any official documentation that clarifies this behavior for external snapshots, as most documentation seems to focus on internal snapshots? The semantics of external and internal snapshots are supposed to be indentical. I don't think we document to a deep extent the actual behaviour WRT to the disk files.

2 1

[PATCH v2] virhostcpu: Fix potential use of unallocated memory
by Felix Huettner 26 Mar '26

26 Mar '26

In case of a host that has a large number of cpus offline the count of host cpus and the last bit set in the virHostCPUGetOnlineBitmap might diverge significantly. This can e.g. be the case when disabling smt via /sys/devices/system/cpu/smt/control. On the host this looks like: ``` $ cat /sys/devices/system/cpu/present 0-255 $ cat /sys/devices/system/cpu/online 0-127 ``` However in this case virBitmapToData previously only allocated 16 bytes for the output bitmap. This is becase the last set bit is on the 15th byte. Users of virHostCPUGetMap however rely on the "cpumap" containing enough space for all existing cpus (so they would expect 32 bytes in this case). E.g. cmdNodeCpuMap relies on this for its output. It will then actually read 32 bytes from the start of the "cpumap" address where in this case the last 16 of these bytes are uninitialized. This manifests itself in flapping outputs of "virsh nodecpumap --pretty" like: ``` $ virsh nodecpumap --pretty CPUs present: 256 CPUs online: 128 CPU map: 0-127,192,194,202 $ virsh nodecpumap --pretty CPUs present: 256 CPUs online: 128 CPU map: 0-127,192,194,197 $ virsh nodecpumap --pretty CPUs present: 256 CPUs online: 128 CPU map: 0-127,192,194,196-197 ``` This in turn potentially causes users of this data to report wrong cpu counts. Note that this only seems to happen with at least 256 physical cpus where at least 128 are offline. We fix this by preallocating the expected bitmap size. Signed-off-by: Felix Huettner <felix.huettner(a)stackit.cloud> --- src/util/virhostcpu.c | 22 ++++++++++------------ 1 file changed, 10 insertions(+), 12 deletions(-) diff --git a/src/util/virhostcpu.c b/src/util/virhostcpu.c index 5dbcc8987c..4805484b1d 100644 --- a/src/util/virhostcpu.c +++ b/src/util/virhostcpu.c @@ -1090,28 +1090,26 @@ virHostCPUGetMap(unsigned char **cpumap, unsigned int flags) { g_autoptr(virBitmap) cpus = NULL; - int ret = -1; - int dummy; + int ncpus = virHostCPUGetCount(); virCheckFlags(0, -1); if (!cpumap && !online) - return virHostCPUGetCount(); + return ncpus; if (!(cpus = virHostCPUGetOnlineBitmap())) - goto cleanup; + return -1; + + if (cpumap) { + int len = (ncpus + CHAR_BIT) / CHAR_BIT; + *cpumap = g_new0(unsigned char, len); + virBitmapToDataBuf(cpus, *cpumap, len); + } - if (cpumap) - virBitmapToData(cpus, cpumap, &dummy); if (online) *online = virBitmapCountBits(cpus); - ret = virHostCPUGetCount(); - - cleanup: - if (ret < 0 && cpumap) - VIR_FREE(*cpumap); - return ret; + return ncpus; } base-commit: c5a73f75bc6cae4f466d0a6344d5b3277ac9c2f4 -- 2.43.0

2 1

[PATCH 0/3] Add 'scalable_mode' and 'first_stage' attributes to intel IOMMU
by Zhenzhong Duan 06 Mar '26

06 Mar '26

Hi, This adds 'scalable_mode' and 'first_stage' attributes to intel IOMMU so that emulated device can run with first stage translation. This is based on Nathan Chen's iommufd series v2[1], so for passthrough device, nested tranlation is enabled automatically with below config: <iommu model='intel'> <driver caching_mode='on' iotlb='on' scalable_mode='on' first_stage='on'/> </iommu> Tests: Basic net card passthrough libvirt selftest Thanks Zhenzhong [1] https://lists.libvirt.org/archives/list/devel@lists.libvirt.org/thread/KFYU… Zhenzhong Duan (3): qemu: Introduce scalable_mode and first_stage capabilities conf: add support for 'scalable_mode' and 'first_stage' attributes to intel IOMMU qemu: Add command line support for scalable mode and first stage of virtual vtd docs/formatdomain.rst | 8 +++++ src/conf/domain_conf.c | 35 ++++++++++++++++++- src/conf/domain_conf.h | 2 ++ src/conf/domain_validate.c | 6 ++++ src/conf/schemas/domaincommon.rng | 10 ++++++ src/qemu/qemu_capabilities.c | 4 +++ src/qemu/qemu_capabilities.h | 2 ++ src/qemu/qemu_command.c | 2 ++ src/qemu/qemu_validate.c | 12 +++++++ .../caps_10.0.0_x86_64+amdsev.xml | 2 ++ .../caps_10.0.0_x86_64.xml | 2 ++ .../caps_10.1.0_x86_64+inteltdx.xml | 2 ++ .../caps_10.1.0_x86_64.xml | 2 ++ .../caps_10.2.0_x86_64.xml | 2 ++ .../caps_6.2.0_x86_64.xml | 1 + .../caps_7.0.0_x86_64.xml | 1 + .../caps_7.1.0_x86_64.xml | 1 + .../caps_7.2.0_x86_64+hvf.xml | 1 + .../caps_7.2.0_x86_64.xml | 1 + .../caps_8.0.0_x86_64.xml | 1 + .../caps_8.1.0_x86_64.xml | 1 + .../caps_8.2.0_x86_64.xml | 1 + .../caps_9.0.0_x86_64.xml | 1 + .../caps_9.1.0_x86_64.xml | 1 + .../caps_9.2.0_x86_64+amdsev.xml | 1 + .../caps_9.2.0_x86_64.xml | 1 + 26 files changed, 102 insertions(+), 1 deletion(-) -- 2.47.3

3 7

[PULL 02/18] deprecation: don't enable TCG plugins by default with TCI
by Alex Bennée 27 Feb '26

27 Feb '26

The softmmu memory instrumentation test sees so many more accesses than a normal translated host and its really not worth fixing up. Lets deprecate this odd configuration and save on the CI cycles. Reviewed-by: Pierrick Bouvier <pierrick.bouvier(a)linaro.org> Signed-off-by: Alex Bennée <alex.bennee(a)linaro.org> Message-Id: <20240916085400.1046925-3-alex.bennee(a)linaro.org> diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 809b2b9b81..c0aa52def5 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -196,6 +196,14 @@ benefits from having plenty of host memory it seems reasonable to encourage users to use 64 bit builds of QEMU for analysis work whatever targets they are instrumenting. +TCG Plugin support not enabled by default with TCI (since 9.2) +'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' + +While the TCG interpreter can interpret the TCG ops used by plugins it +is going to be so much slower it wouldn't make sense for any serious +instrumentation. Due to implementation differences there will also be +anomalies in things like memory instrumentation. + System emulator CPUs -------------------- diff --git a/configure b/configure index cc8e1ed5b8..aa7aae70fa 100755 --- a/configure +++ b/configure @@ -629,6 +629,9 @@ meson_option_parse() { exit 1 fi } +has_meson_option() { + test "${meson_options#*"$1"}" != "$meson_options" +} meson_add_machine_file() { if test "$cross_compile" = "yes"; then @@ -1048,8 +1051,12 @@ if test "$static" = "yes" ; then plugins="no" fi if test "$plugins" != "no" && test $host_bits -eq 64; then - plugins=yes - subdirs="$subdirs contrib/plugins" + if has_meson_option "-Dtcg_interpreter=true"; then + plugins="no" + else + plugins=yes + subdirs="$subdirs contrib/plugins" + fi fi cat > $TMPC << EOF -- 2.39.5

2 1

[PATCH v2 0/2] allow migrations with the ext transport
by Sergey Dyasli 19 Feb '26

19 Feb '26

Hello, I have a use case for live-migration where the socket of the destination libvirtd is proxied by an mTLS WebSocket proxy. Since there is no WebSocket support in Libvirt, I've decided to use the existing ext transport and point it to a proxy binary on the source host of live-migration. While doing that, I've discovered a couple of roadblocks: 1. There is no way of passing cmdline arguments to the ext program 2. Live-migrations using ext transport fail localhost checks This short series addresses those limitations. Sergey Dyasli (2): remote: allow passing argv to the ext transport remote: allow migrations with the ext transport v1 -> v2: - new way of passing argv src/libvirt-domain.c | 8 +++++--- src/remote/remote_driver.c | 30 ++++++++++++++++++++++++++---- src/util/viruri.c | 32 ++++++++++++++++++++++++++++++++ src/util/viruri.h | 2 ++ 4 files changed, 65 insertions(+), 7 deletions(-) -- 2.43.7

3 5

[PATCH v6] qapi: net: deprecate vhostforce option
by Vladimir Sementsov-Ogievskiy 18 Feb '26

18 Feb '26

This option for tap and vhost-user netdevs doesn't make sense since long ago (10 years!), starting from commits: 1e7398a140f7a6 ("vhost: enable vhost without without MSI-X") 24f938a682d934 ("vhost user:support vhost user nic for non msi guests") Prior these commits, to enable kernel vhost-net, or vhost-user-net for some specific kind of guests (that don't have MSI-X support), you should have set vhostforce=on. Now guest type doesn't matter, all guests are equal for these options logic. For tap the current logic is: vhost=on / vhost=off : vhostforce ignored, doesn't make sense vhost unset : vhostforce counts, enabling vhost So you may enable vhost for tap several ways: - vhost=on - vhostforce=on - vhost=on + vhostforce=on - and even vhost=on + vhostforce=off - they are all equal. For vhost-user we simply ignore the vhostforce option at all in the code. Let's finally deprecate the extra options. Also, fix @vhostforce documentation everywhere to show the real picture, and update vhost-user test to not use deprecated option. While updating command line options, drop "experimental" word from "experimental in kernel accelerator". vhost-net is in production for years. Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov(a)yandex-team.ru> Reviewed-by: Markus Armbruster <armbru(a)redhat.com> --- v6: - update numbers 10.2 -> 11.0 - add r-b by Markus docs/about/deprecated.rst | 11 +++++++++++ qapi/net.json | 18 ++++++++++++++---- qemu-options.hx | 13 +++++-------- tests/qtest/vhost-user-test.c | 2 +- 4 files changed, 31 insertions(+), 13 deletions(-) diff --git a/docs/about/deprecated.rst b/docs/about/deprecated.rst index 03e29915f0..3f97392a45 100644 --- a/docs/about/deprecated.rst +++ b/docs/about/deprecated.rst @@ -498,6 +498,17 @@ Backend ``memory`` (since 9.0) ``memory`` is a deprecated synonym for ``ringbuf``. +TAP ``vhostforce`` (since 11.0) +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The ``vhostforce`` option is redundant with the ``vhost`` option. +If they conflict, ``vhost`` takes precedence. Just use ``vhost``. + +Vhost-user ``vhostforce`` (since 11.0) +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The ``vhostforce`` option is a no-op. Do not use it. + CPU device properties ''''''''''''''''''''' diff --git a/qapi/net.json b/qapi/net.json index 118bd34965..9a00d578e9 100644 --- a/qapi/net.json +++ b/qapi/net.json @@ -348,13 +348,18 @@ # @vhostfds: file descriptors of multiple already opened vhost net # devices # -# @vhostforce: vhost on for non-MSIX virtio guests +# @vhostforce: enable vhost-net network accelerator. Ignored when +# @vhost is set. # # @queues: number of queues to be created for multiqueue capable tap # # @poll-us: maximum number of microseconds that could be spent on busy # polling for tap (since 2.7) # +# Features: +# +# @deprecated: Member @vhostforce is deprecated. Use @vhost instead. +# # Since: 1.2 ## { 'struct': 'NetdevTapOptions', @@ -371,7 +376,7 @@ '*vhost': 'bool', '*vhostfd': 'str', '*vhostfds': 'str', - '*vhostforce': 'bool', + '*vhostforce': { 'type': 'bool', 'features': [ 'deprecated' ] }, '*queues': 'uint32', '*poll-us': 'uint32'} } @@ -610,17 +615,22 @@ # # @chardev: name of a unix socket chardev # -# @vhostforce: vhost on for non-MSIX virtio guests (default: false). +# @vhostforce: silently ignored, exists just for backward +# compatibility. # # @queues: number of queues to be created for multiqueue vhost-user # (default: 1) (Since 2.5) # +# Features: +# +# @deprecated: Member @vhostforce is deprecated. +# # Since: 2.1 ## { 'struct': 'NetdevVhostUserOptions', 'data': { 'chardev': 'str', - '*vhostforce': 'bool', + '*vhostforce': { 'type': 'bool', 'features': [ 'deprecated' ] }, '*queues': 'int' } } ## diff --git a/qemu-options.hx b/qemu-options.hx index fca2b7bc74..414b762743 100644 --- a/qemu-options.hx +++ b/qemu-options.hx @@ -2882,7 +2882,7 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, #else "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" - " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" + " [,vhostfd=h][,vhostfds=x:y:...:z][,queues=n]\n" " [,poll-us=n]\n" " configure a host TAP network backend with ID 'str'\n" " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" @@ -2898,9 +2898,7 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" - " use vhost=on to enable experimental in kernel accelerator\n" - " (only has effect for virtio guests which use MSIX)\n" - " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" + " use vhost=on to enable in kernel accelerator\n" " use 'vhostfd=h' to connect to an already opened vhost net device\n" " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" @@ -2991,7 +2989,7 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, " use 'start-queue=m' to specify the first queue that should be used\n" #endif #ifdef CONFIG_POSIX - "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" + "-netdev vhost-user,id=str,chardev=dev\n" " configure a vhost-user network, backed by a chardev 'dev'\n" #endif #ifdef __linux__ @@ -3882,12 +3880,11 @@ SRST for insertion into the socket map. The combination of 'map-path' and 'sock-fds' together is not supported. -``-netdev vhost-user,chardev=id[,vhostforce=on|off][,queues=n]`` +``-netdev vhost-user,chardev=id[,queues=n]`` Establish a vhost-user netdev, backed by a chardev id. The chardev should be a unix domain socket backed one. The vhost-user uses a specifically defined protocol to pass vhost ioctl replacement - messages to an application on the other end of the socket. On - non-MSIX guests, the feature can be forced with vhostforce. Use + messages to an application on the other end of the socket. Use 'queues=n' to specify the number of queues to be created for multiqueue vhost-user. diff --git a/tests/qtest/vhost-user-test.c b/tests/qtest/vhost-user-test.c index d2bb21d5b9..f977f50baf 100644 --- a/tests/qtest/vhost-user-test.c +++ b/tests/qtest/vhost-user-test.c @@ -46,7 +46,7 @@ #define QEMU_CMD_SHM " -m %d -object memory-backend-shm,id=mem,size=%dM," \ " -numa node,memdev=mem" #define QEMU_CMD_CHR " -chardev socket,id=%s,path=%s%s" -#define QEMU_CMD_NETDEV " -netdev vhost-user,id=hs0,chardev=%s,vhostforce=on" +#define QEMU_CMD_NETDEV " -netdev vhost-user,id=hs0,chardev=%s" #define HUGETLBFS_MAGIC 0x958458f6 -- 2.48.1

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[PATCH v3 0/7] USB hostdev: allow addressing by port
by Maximilian Martin 11 Feb '26

11 Feb '26

Currently, only vendor/product and bus/device matching are supported for USB host devices. Neither of these provide a stable and persistent way of assigning a guest a specific host device. Vendor/product can be ambiguous. Device numbers change on every enumeration. This patch adds a bus/port matching, which allows a specific port on the host to be specified using the dotted notation found in Linux's "devpath" sysfs attribute. The path series is based on the previous work of Thomas Hebb: https://lists.libvirt.org/archives/list/devel@lists.libvirt.org/message/7U3… This resubmission includes Daniel's patch which extends the USB hostdev test logic. Maximilian Martin (7): tests: validate an XML config with USB vendor/product set virusb test data: add devpath files for port addressing domain_conf, virhostdev, virusb, virusb test: add bus/port matching schema: add USB port attribute tests: validate an XML config with USB bus/port set nodedev: add USB port to nodedev XML docs: add description for USB port matching docs/formatdomain.rst | 29 ++-- src/conf/domain_conf.c | 58 ++++++- src/conf/domain_conf.h | 1 + src/conf/node_device_conf.c | 5 + src/conf/node_device_conf.h | 1 + src/conf/schemas/basictypes.rng | 31 ++++ src/conf/schemas/domaincommon.rng | 41 +---- src/conf/schemas/nodedev.rng | 3 + src/hypervisor/virhostdev.c | 131 ++++++++------ src/libvirt_private.syms | 2 - src/node_device/node_device_udev.c | 4 + src/util/virusb.c | 160 ++++++------------ src/util/virusb.h | 22 +-- .../usb_device_1d6b_1_0000_00_1d_0.xml | 1 + ...ostdev-usb-address-port.x86_64-latest.args | 36 ++++ ...hostdev-usb-address-port.x86_64-latest.xml | 45 +++++ .../hostdev-usb-address-port.xml | 28 +++ ...tdev-usb-vendor-product.x86_64-latest.args | 35 ++++ ...stdev-usb-vendor-product.x86_64-latest.xml | 44 +++++ .../hostdev-usb-vendor-product.xml | 36 ++++ tests/qemuxmlconftest.c | 25 +++ tests/virusbtest.c | 149 +++++++++++----- .../sys_bus_usb/devices/1-1.5.3.1/devpath | 1 + .../sys_bus_usb/devices/1-1.5.3.3/devpath | 1 + .../sys_bus_usb/devices/1-1.5.3/devpath | 1 + .../sys_bus_usb/devices/1-1.5.4/devpath | 1 + .../sys_bus_usb/devices/1-1.5.5/devpath | 1 + .../sys_bus_usb/devices/1-1.5.6/devpath | 1 + .../sys_bus_usb/devices/1-1.5/devpath | 1 + .../sys_bus_usb/devices/1-1.6/devpath | 1 + .../sys_bus_usb/devices/1-1/devpath | 1 + .../sys_bus_usb/devices/2-1.2/devpath | 1 + .../sys_bus_usb/devices/2-1/devpath | 1 + .../sys_bus_usb/devices/usb1/devpath | 1 + .../sys_bus_usb/devices/usb2/devpath | 1 + .../sys_bus_usb/devices/usb3/devpath | 1 + .../sys_bus_usb/devices/usb4/devpath | 1 + 37 files changed, 631 insertions(+), 271 deletions(-) create mode 100644 tests/qemuxmlconfdata/hostdev-usb-address-port.x86_64-latest.args create mode 100644 tests/qemuxmlconfdata/hostdev-usb-address-port.x86_64-latest.xml create mode 100644 tests/qemuxmlconfdata/hostdev-usb-address-port.xml create mode 100644 tests/qemuxmlconfdata/hostdev-usb-vendor-product.x86_64-latest.args create mode 100644 tests/qemuxmlconfdata/hostdev-usb-vendor-product.x86_64-latest.xml create mode 100644 tests/qemuxmlconfdata/hostdev-usb-vendor-product.xml create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.5.3.1/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.5.3.3/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.5.3/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.5.4/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.5.5/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.5.6/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.5/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1.6/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/1-1/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/2-1.2/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/2-1/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/usb1/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/usb2/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/usb3/devpath create mode 100644 tests/virusbtestdata/sys_bus_usb/devices/usb4/devpath -- 2.39.5

3 13

Qemu pause-before-switchover and libvirt live migration
by Rogério Vinhal Nunes 02 Feb '26

02 Feb '26

Hello, I’m looking into the libvirt hooks that are available to make use of during a live migration, but there's only hooks on migration begin and migration end. On qemu directly I’m able to use pause-before-switchover migration capability to run a custom operation just before it moves to the destination, but within libvirt it seems that while this is leveraged internally, it’s not currently exposed to the client in a way I can use. Does anyone have any suggestions on how I could expose this to the client in a generic and sensible way? Thanks, Rogerio

3 11