May 2021 - Devel - libvirt List Archives

[libvirt] [PATCH] Fix python error reporting for some storage operations
by Cole Robinson 07 Mar '25

07 Mar '25

In the python bindings, all vir* classes expect to be passed a virConnect object when instantiated. Before the storage stuff, these classes were only instantiated in virConnect methods, so the generator is hardcoded to pass 'self' as the connection instance to these classes. Problem is there are some methods that return pool or vol instances which aren't called from virConnect: you can lookup a storage volume's associated pool, and can lookup volumes from a pool. In these cases passing 'self' doesn't give the vir* instance a connection, so when it comes time to raise an exception crap hits the fan. Rather than rework the generator to accomodate this edge case, I just fixed the init functions for virStorage* to pull the associated connection out of the passed value if it's not a virConnect instance. Thanks, Cole diff --git a/python/generator.py b/python/generator.py index 01a17da..c706b19 100755 --- a/python/generator.py +++ b/python/generator.py @@ -962,8 +962,12 @@ def buildWrappers(): list = reference_keepers[classname] for ref in list: classes.write(" self.%s = None\n" % ref[1]) - if classname in [ "virDomain", "virNetwork", "virStoragePool", "virStorageVol" ]: + if classname in [ "virDomain", "virNetwork" ]: classes.write(" self._conn = conn\n") + elif classname in [ "virStorageVol", "virStoragePool" ]: + classes.write(" self._conn = conn\n" + \ + " if not isinstance(conn, virConnect):\n" + \ + " self._conn = conn._conn\n") classes.write(" if _obj != None:self._o = _obj;return\n") classes.write(" self._o = None\n\n"); destruct=None

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Re: [libvirt] [Qemu-devel] Qemu migration with vhost-user-blk on top of local storage
by Stefan Hajnoczi 27 Oct '23

27 Oct '23

On Wed, Jan 09, 2019 at 06:23:42PM +0800, wuzhouhui wrote: > Hi everyone, > > I'm working qemu with vhost target (e.g. spdk), and I attempt to migrate VM with > 2 local storages. One local storage is a regular file, e.g. /tmp/c74.qcow2, and > the other is a malloc bdev that spdk created. This malloc bdev will exported to > VM via vhost-user-blk. When I execute following command: > > virsh migrate --live --persistent --unsafe --undefinesource --copy-storage-all \ > --p2p --auto-converge --verbose --desturi qemu+tcp://<uri>/system vm0 > > The libvirt reports: > > qemu-2.12.1: error: internal error: unable to execute QEMU command \ > 'nbd-server-add': Cannot find device=drive-virtio-disk1 nor \ > node_name=drive-virtio-disk1 Please post your libvirt domain XML. > Does it means that qemu with spdk on top of local storage don't support migration? > > QEMU: 2.12.1 > SPDK: 18.10 vhost-user-blk bypasses the QEMU block layer, so NBD storage migration at the QEMU level will not work for the vhost-user-blk disk. Stefan

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[libvirt] [PATCH v3] openvswitch: Add new port VLAN mode "dot1q-tunnel"
by luzhipeng＠uniudc.com 27 Oct '23

27 Oct '23

From: ZhiPeng Lu <luzhipeng(a)uniudc.com> Signed-off-by: ZhiPeng Lu <luzhipeng(a)uniudc.com> --- v1->v2: 1. Fix "make syntax-check" failure v2->v3: 1. remove other_config when updating vlan docs/formatnetwork.html.in | 17 +++++++++-------- docs/schemas/networkcommon.rng | 1 + src/conf/netdev_vlan_conf.c | 2 +- src/util/virnetdevopenvswitch.c | 7 +++++++ src/util/virnetdevvlan.h | 1 + 5 files changed, 19 insertions(+), 9 deletions(-) diff --git a/docs/formatnetwork.html.in b/docs/formatnetwork.html.in index 363a72b..3c1ae62 100644 --- a/docs/formatnetwork.html.in +++ b/docs/formatnetwork.html.in @@ -688,16 +688,17 @@ For network connections using Open vSwitch it is also possible - to configure 'native-tagged' and 'native-untagged' VLAN modes + to configure 'native-tagged' and 'native-untagged' and 'dot1q-tunnel' + VLAN modes. Since 1.1.0. This is done with the - optional <code>nativeMode</code> attribute on - the <code><tag></code> subelement: <code>nativeMode</code> - may be set to 'tagged' or 'untagged'. The <code>id</code> - attribute of the <code><tag></code> subelement - containing <code>nativeMode</code> sets which VLAN is considered - to be the "native" VLAN for this interface, and + optional <code>nativeMode</code> attribute on the + <code><tag></code> subelement: <code>nativeMode</code> + may be set to 'tagged' or 'untagged' or 'dot1q-tunnel'. + The <code>id</code> attribute of the <code><tag></code> + subelement containing <code>nativeMode</code> sets which VLAN is + considered to be the "native" VLAN for this interface, and the <code>nativeMode</code> attribute determines whether or not - traffic for that VLAN will be tagged. + traffic for that VLAN will be tagged or QinQ. <code><vlan></code> elements can also be specified in diff --git a/docs/schemas/networkcommon.rng b/docs/schemas/networkcommon.rng index 2699555..11c48ff 100644 --- a/docs/schemas/networkcommon.rng +++ b/docs/schemas/networkcommon.rng @@ -223,6 +223,7 @@ <choice> <value>tagged</value> <value>untagged</value> + <value>dot1q-tunnel</value> </choice> </attribute> </optional> diff --git a/src/conf/netdev_vlan_conf.c b/src/conf/netdev_vlan_conf.c index dff49c6..79710d9 100644 --- a/src/conf/netdev_vlan_conf.c +++ b/src/conf/netdev_vlan_conf.c @@ -29,7 +29,7 @@ #define VIR_FROM_THIS VIR_FROM_NONE VIR_ENUM_IMPL(virNativeVlanMode, VIR_NATIVE_VLAN_MODE_LAST, - "default", "tagged", "untagged") + "default", "tagged", "untagged", "dot1q-tunnel") int virNetDevVlanParse(xmlNodePtr node, xmlXPathContextPtr ctxt, virNetDevVlanPtr def) diff --git a/src/util/virnetdevopenvswitch.c b/src/util/virnetdevopenvswitch.c index 8fe06fd..9fec30b 100644 --- a/src/util/virnetdevopenvswitch.c +++ b/src/util/virnetdevopenvswitch.c @@ -91,6 +91,11 @@ virNetDevOpenvswitchConstructVlans(virCommandPtr cmd, virNetDevVlanPtr virtVlan) virCommandAddArg(cmd, "vlan_mode=native-untagged"); virCommandAddArgFormat(cmd, "tag=%d", virtVlan->nativeTag); break; + case VIR_NATIVE_VLAN_MODE_DOT1Q_TUNNEL: + virCommandAddArg(cmd, "vlan_mode=dot1q-tunnel"); + virCommandAddArg(cmd, "other_config:qinq-ethtype=802.1q"); + virCommandAddArgFormat(cmd, "tag=%d", virtVlan->nativeTag); + break; case VIR_NATIVE_VLAN_MODE_DEFAULT: default: break; @@ -504,6 +509,8 @@ int virNetDevOpenvswitchUpdateVlan(const char *ifname, "--", "--if-exists", "clear", "Port", ifname, "tag", "--", "--if-exists", "clear", "Port", ifname, "trunk", "--", "--if-exists", "clear", "Port", ifname, "vlan_mode", + "--", "--if-exists", "remove", "Port", ifname, "other_config", + "qinq-ethtype", NULL, "--", "--if-exists", "set", "Port", ifname, NULL); if (virNetDevOpenvswitchConstructVlans(cmd, virtVlan) < 0) diff --git a/src/util/virnetdevvlan.h b/src/util/virnetdevvlan.h index be85f59..0667f9d 100644 --- a/src/util/virnetdevvlan.h +++ b/src/util/virnetdevvlan.h @@ -29,6 +29,7 @@ typedef enum { VIR_NATIVE_VLAN_MODE_DEFAULT = 0, VIR_NATIVE_VLAN_MODE_TAGGED, VIR_NATIVE_VLAN_MODE_UNTAGGED, + VIR_NATIVE_VLAN_MODE_DOT1Q_TUNNEL, VIR_NATIVE_VLAN_MODE_LAST } virNativeVlanMode; -- 1.8.3.1

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[libvirt] [PATCH] Fix compile error for stable 1.2.9
by Yang hongyang 27 Oct '23

27 Oct '23

Seems a backport miss. An extra member is passed to struct virLXCBasicMountInfo. Signed-off-by: Yang hongyang <hongyang.yang(a)easystack.cn> --- src/lxc/lxc_container.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c index 28dabec..1c65fa9 100644 --- a/src/lxc/lxc_container.c +++ b/src/lxc/lxc_container.c @@ -760,7 +760,7 @@ typedef struct { static const virLXCBasicMountInfo lxcBasicMounts[] = { { "proc", "/proc", "proc", MS_NOSUID|MS_NOEXEC|MS_NODEV, false, false }, - { "/proc/sys", "/proc/sys", NULL, MS_BIND|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, false, false, false }, + { "/proc/sys", "/proc/sys", NULL, MS_BIND|MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, false, false }, { "sysfs", "/sys", "sysfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, false, false }, { "securityfs", "/sys/kernel/security", "securityfs", MS_NOSUID|MS_NOEXEC|MS_NODEV|MS_RDONLY, true, true }, #if WITH_SELINUX -- 1.7.1

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[libvirt] [PATCH] web docs -- macvtap mode explanation
by Stefan Berger 27 Oct '23

27 Oct '23

This adds more information about the different macvtap device modes. Regards, Stefan

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[libvirt] Supporting vhost-net and macvtap in libvirt for QEMU
by Anthony Liguori 27 Oct '23

27 Oct '23

Disclaimer: I am neither an SR-IOV nor a vhost-net expert, but I've CC'd people that are who can throw tomatoes at me for getting bits wrong :-) I wanted to start a discussion about supporting vhost-net in libvirt. vhost-net has not yet been merged into qemu but I expect it will be soon so it's a good time to start this discussion. There are two modes worth supporting for vhost-net in libvirt. The first mode is where vhost-net backs to a tun/tap device. This is behaves in very much the same way that -net tap behaves in qemu today. Basically, the difference is that the virtio backend is in the kernel instead of in qemu so there should be some performance improvement. Current, libvirt invokes qemu with -net tap,fd=X where X is an already open fd to a tun/tap device. I suspect that after we merge vhost-net, libvirt could support vhost-net in this mode by just doing -net vhost,fd=X. I think the only real question for libvirt is whether to provide a user visible switch to use vhost or to just always use vhost when it's available and it makes sense. Personally, I think the later makes sense. The more interesting invocation of vhost-net though is one where the vhost-net device backs directly to a physical network card. In this mode, vhost should get considerably better performance than the current implementation. I don't know the syntax yet, but I think it's reasonable to assume that it will look something like -net tap,dev=eth0. The effect will be that eth0 is dedicated to the guest. On most modern systems, there is a small number of network devices so this model is not all that useful except when dealing with SR-IOV adapters. In that case, each physical device can be exposed as many virtual devices (VFs). There are a few restrictions here though. The biggest is that currently, you can only change the number of VFs by reloading a kernel module so it's really a parameter that must be set at startup time. I think there are a few ways libvirt could support vhost-net in this second mode. The simplest would be to introduce a new tag similar to <source network='br0'>. In fact, if you probed the device type for the network parameter, you could probably do something like <source network='eth0'> and have it Just Work. Another model would be to have libvirt see an SR-IOV adapter as a network pool whereas it handled all of the VF management. Considering how inflexible SR-IOV is today, I'm not sure whether this is the best model. Has anyone put any more thought into this problem or how this should be modeled in libvirt? Michael, could you share your current thinking for -net syntax? -- Regards, Anthony Liguori

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[libvirt] Semantic change in v4.3 slows down image creation and snapshots (on ZFS)
by Christian Ehrhardt 31 Jul '22

31 Jul '22

Hi, when discussing bug [1] triggered by [2] Daniel and I have found that the change [3] which is in since v4.3 was a semantic change to the behavior of libvirt. virt-manager used and still does issue a volume XML like: <volume> <name>disk.qcow2</name> <capacity>16106127360</capacity> <allocation>16106127360</allocation> <target> <format type="qcow2"/> <features> <lazy_refcounts/> </features> </target> </volume> Up until the commit above that was using preallocation=metadata, but now uses preallocation=falloc. In many cases (read: Fileystems) that won't be very user-visible, but if you are running on ZFS (or anything else that can't fallocate well) this is made worse by [4] slowing down these operations a lot. After the POV for virt-manager seems to have settled on the bug [1] referenced the remaining question is if libvirt should revert/modify the change [3] - and that we agreed required a wider discussion to be had here, hence this mail. [1]: https://bugzilla.redhat.com/show_bug.cgi?id=1759454 [2]: https://bugs.launchpad.net/virt-manager/+bug/1847105 [3]: https://libvirt.org/git/?p=libvirt.git;a=commit;h=c9ec7088c7a3f4cd26bb471f1… [4]: https://github.com/zfsonlinux/zfs/issues/326 -- Christian Ehrhardt Software Engineer, Ubuntu Server Canonical Ltd

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[PATCH v2 00/19] Refactoring conf to use XPath
by Kristina Hanicova 25 Mar '22

25 Mar '22

This is v2 from https://listman.redhat.com/archives/libvir-list/2021-April/msg00617.html Changes since v1: - rebase to the lastest git master This series reworks the outdated way of parsing XML to parsing by XPath, which is more obvious and saves a few lines of code. Kristina Hanicova (19): conf: Propagate xmlXPathContextPtr into virDomainHostdevSubsysUSBDefParseXML() Refactoring virDomainHostdevSubsysUSBDefParseXML() to use XPath conf: Propagate xmlXPathContextPtr into virDomainBlkioDeviceParseXML() Refactoring virDomainBlkioDeviceParseXML() to use XPath conf: Propagate xmlXPathContextPtr into virDomainHostdevSubsysPCIDefParseXML() Refactoring virDomainHostdevSubsysPCIDefParseXML() to use XPath conf: Propagate xmlXPathContextPtr into virDomainLeaseDefParseXML() Refactoring virDomainLeaseDefParseXML() to use XPath Refactoring virDomainFSDefParseXML() to use XPath Refactoring virDomainNetDefParseXML() to use XPath conf: Propagate xmlXPathContextPtr into virDomainChrDefParseTargetXML() Refactoring virDomainChrDefParseTargetXML() to use XPath Refactoring virDomainChrSourceDefParseXML() to use XPath Refactoring virDomainChrDefParseXML() to use XPath Refactoring virDomainSmartcardDefParseXML() to use XPath Refactoring virDomainGraphicsDefParseXMLSpice() to use XPath conf: Propagate xmlXPathContextPtr into virDomainVideoDriverDefParseXML() Refactoring virDomainVideoDriverDefParseXML() to use XPath Refactoring virDomainVideoDefParseXML() to use XPath src/conf/domain_conf.c | 1641 +++++++++++++++++----------------------- 1 file changed, 707 insertions(+), 934 deletions(-) -- 2.30.2

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[libvirt PATCH] qemu_firmware: don't error out for unknown firmware features
by Pavel Hrdina 31 Jan '22

31 Jan '22

When QEMU introduces new firmware features libvirt will fail until we list that feature in our code as well which doesn't sound right. We should simply ignore the new feature until we add a proper support for it. Reported-by: Laszlo Ersek <lersek(a)redhat.com> Signed-off-by: Pavel Hrdina <phrdina(a)redhat.com> --- src/qemu/qemu_firmware.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/src/qemu/qemu_firmware.c b/src/qemu/qemu_firmware.c index 94e88ebe4b..e37a7edefa 100644 --- a/src/qemu/qemu_firmware.c +++ b/src/qemu/qemu_firmware.c @@ -567,6 +567,7 @@ qemuFirmwareFeatureParse(const char *path, virJSONValue *featuresJSON; g_autoptr(qemuFirmwareFeature) features = NULL; size_t nfeatures; + size_t nparsed = 0; size_t i; if (!(featuresJSON = virJSONValueObjectGetArray(doc, "features"))) { @@ -586,17 +587,16 @@ qemuFirmwareFeatureParse(const char *path, int tmp; if ((tmp = qemuFirmwareFeatureTypeFromString(tmpStr)) <= 0) { - virReportError(VIR_ERR_INTERNAL_ERROR, - _("unknown feature %s"), - tmpStr); - return -1; + VIR_DEBUG("unknown feature %s", tmpStr); + continue; } - features[i] = tmp; + features[nparsed] = tmp; + nparsed++; } fw->features = g_steal_pointer(&features); - fw->nfeatures = nfeatures; + fw->nfeatures = nparsed; return 0; } -- 2.30.2

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[RFC] Allowing SEV attestation
by Michal Prívozník 29 Oct '21

29 Oct '21

Dear list, in the light of recent development of secure virtualization (for instance AMD SEV-SNP [1]) I'd like us to be prepared for when QEMU adopts these new technologies and thus would like to discuss our options. So far, I've came across AMD SEV-SNP [2]. While it's true that we do support SEV, we need to adopt its newer version too. Consider the following example: you loan a VM on a public cloud and you want to process some private data there. Of course, the data has to be stored on an encrypted disk/partition. But encrypting guest memory (confidentiality) prevents you only from finding the key in a memory dump. It doesn't help if the guest image, initial guest memory, hypervisor or firmware were tampered with. This is where attestation comes to help - it enables the guest owner (which in this example is different to the one running it) verify - with cryptographic level of confidence - that data confidentiality and integrity can be ensured. Depending on the technology, attestation will be done at different times in the VM lifecycle. When it's done before starting guest vCPUs, it's called pre-attestation and when it's done after the guest has launched, it's called post-attestation. For example, AMD SEV and SEV-ES require pre-attestation. SEV-SNP allows for post attestation. The crux of the issue here is that *when* and *how* the guest owner will interact with the VM for attestation will be different depending on which technology is being used. It looks like QEMU will expose commands needed for attestation via QMP [3]. But question then is, how to expose those at Libvirt level? Should we allow users to bypass Libvirt and communicate to QEMU directly or wrap those QMPs in public APIs, or something completely different? Will those APIs be generic enough to serve other technologies too? For instance, given set of APIs in given order works for SEV but might not work for Intel's TDX. 1: https://kvmforum2019.sched.com/event/Tmwl/improving-and-expanding-sev-suppo… 2: https://www.amd.com/system/files/TechDocs/SEV-SNP-strengthening-vm-isolatio… 3: https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg03689.html Michal

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