virtlogd.socket: Tie lifecycle to libvirtd.service
We already guarantee that virtlogd.socket is enabled/disabled
along with libvirtd.service, but if libvirtd.service has just
been installed and is started before rebooting, then
virtlogd.socket will not be running and guest startup will
fail.
Add Requires=virtlogd.socket to libvirtd.service to make sure
virtlogd.socket is always started along with libvirtd.service,
and add Before=libvirtd.service to both virtlogd.socket and
virtlogd.service so that virtlogd never disappears before
libvirtd has exited.
Also add PartOf=libvirtd.service to both virtlogd.socket and
virtlogd.service, so that virtlogd can be shut down when not
needed.
qemu: allow turning off QEMU guest RAM dump globally
We already have the ability to turn off dumping of guest
RAM via the domain XML. This is not particularly useful
though, as it is under control of the management application.
What is needed is a way for the sysadmin to turn off guest
RAM defaults globally, regardless of whether the mgmt app
provides its own way to set this in the domain XML.
So this adds a 'dump_guest_core' option in /etc/libvirt/qemu.conf
which defaults to false. ie guest RAM will never be included in
the QEMU core dumps by default. This default is different from
historical practice, but is considered to be more suitable as
a default because
a) guest RAM can be huge and so inflicts a DOS on the host
I/O subsystem when dumping core for QEMU crashes
b) guest RAM can contain alot of sensitive data belonging
to the VM owner. This should not generally be copied
around inside QEMU core dumps submitted to vendors for
debugging
c) guest RAM contents are rarely useful in diagnosing
QEMU crashes
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
qemu: add a max_core setting to qemu.conf for core dump size
Currently the QEMU processes inherit their core dump rlimit
from libvirtd, which is really suboptimal. This change allows
their limit to be directly controlled from qemu.conf instead.
With current perf framework, this patch adds support and documentation
for more perf events, including cache misses, cache references, cpu cycles,
and instructions.
Qiaowei Ren [Wed, 3 Aug 2016 17:23:31 +0000 (13:23 -0400)]
perf: Adjust the perf initialization
Introduce a static attr table and refactor virPerfEventEnable() for
general purpose usage.
This patch creates a static table/matrix that converts the VIR_PERF_EVENT_*
events into their respective "attr.type" and "attr.config" so that
virPerfEventEnable doesn't have the switch the calling function passes
by value the 'type'.
qemu: Filter cur_balloon ABI check for certain transactions
Since the domain lock is not held during preparation of an external XML
config, it is possible that the value can change resulting in unexpected
failures during ABI consistency checking for some save and migrate
operations.
This patch adds a new flag to skip the checking of the cur_balloon value
and then sets the destination value to the source value to ensure
subsequent checks without the skip flag will succeed.
This way it is protected from forges and is keeped up to date too.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
Bob Liu [Thu, 18 Aug 2016 02:20:48 +0000 (10:20 +0800)]
libxl: support serial list
Add support for multi serial devices, after this patch virsh can be used to
connect different serial devices of running domains. E.g.
vish # console <xxx> --devname serial<xxx>
Note:
This depends on a xen/libxl bug fix to have libxl_console_get_tty(...) correctly
returning the tty path (as opposed to always returning the first one).
[0] https://lists.xen.org/archives/html/xen-devel/2016-08/msg00438.html
Jim Fehlig [Tue, 2 Aug 2016 03:36:45 +0000 (21:36 -0600)]
virpci: support driver_override sysfs interface
libvirt uses the new_id PCI sysfs interface to bind a PCI stub driver
to a PCI device. The new_id interface is known to be buggy and racey,
hence a more deterministic interface was introduced in the 3.12 kernel:
driver_override. For more details see
This patch adds support for the driver_override interface by
- adding new virPCIDevice{BindTo,UnbindFrom}StubWithOverride functions
that use the driver_override interface
- renames the existing virPCIDevice{BindTo,UnbindFrom}Stub functions
to virPCIDevice{BindTo,UnbindFrom}StubWithNewid to perserve existing
behavior on new_id interface
- changes virPCIDevice{BindTo,UnbindFrom}Stub function to call one of
the above depending on availability of driver_override
The patch includes a bit of duplicate code, but allows for easily
dropping the new_id code once support for older kernels is no
longer desired.
Xian Han Yu [Mon, 15 Aug 2016 04:22:25 +0000 (06:22 +0200)]
conf: Fix initialization value of 'multi' in PCI address
The 'multi' element in PCI address struct used as 'virTristateSwitch',
and its default value is 'VIR_TRISTATE_SWITCH_ABSENT'. Current PCI
process use 'false' to initialization 'multi', which is ambiguously
for assignment or comparison. This patch use '{0}' to initialize
the whole PCI address struct, which fix the 'multi' initialization
and makes code more simplify and explicitly.
Signed-off-by: Xian Han Yu <xhyubj@linux.vnet.ibm.com>
Michal Privoznik [Wed, 31 Aug 2016 10:52:11 +0000 (12:52 +0200)]
tools: Don't list virsh-* under EXTRA_DIST
When we wanted to break huge and unmaintainable virsh into
smaller files first thing we did was to just move funcs into
virsh-.c files and then #include them from virsh. Having it done
this way we also needed to have them listed under EXTRA_DIST.
However, things got changed since then and now all the virsh-*.c
files are proper source files. Therefore they are listed under
virsh_SOURCES too. But for some reason we forgot to remove them
from EXTRA_DIST.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Jim Fehlig [Mon, 29 Aug 2016 16:08:01 +0000 (10:08 -0600)]
libxl: advertise support for migration V3
The libxl driver has long supported migration V3 but has never
indicated so in the connectSupportsFeature API. As a result, apps
such as virt-manager that use the more generic virDomainMigrate API
fail with
libvirtError: this function is not supported by the connection driver:
virDomainMigrate
Add VIR_DRV_FEATURE_MIGRATION_V3 to the list of features marked as
supported in the connectSupportsFeature API.
Test 12 from objecteventtest (createXML add event) segaults on FreeBSD
with bus error.
At some point it calls testNodeDeviceDestroy() from the test driver. And
it fails when it tries to unlock the device in the "out:" label of this
function.
Unlocking fails because the previous step was a call to
virNodeDeviceObjRemove from conf/node_device_conf.c. This function
removes the given device from the device list and cleans up the object,
including destroying of its mutex. However, it does not nullify the pointer
that was given to it.
As a result, we end up in testNodeDeviceDestroy() here:
out:
if (obj)
virNodeDeviceObjUnlock(obj);
And instead of skipping this, we try to do Unlock and fail because of
malformed mutex.
Change virNodeDeviceObjRemove to use double pointer and set pointer to
NULL.
Peter Krempa [Thu, 25 Aug 2016 19:30:21 +0000 (15:30 -0400)]
qemu: driver: Validate configuration when setting maximum vcpu count
Setting vcpu count when cpu topology is specified may result into an
invalid configuration. Since the topology can't be modified, reject the
setting if it doesn't match the requested topology. This will allow
fixing the topology in case it was broken.
Peter Krempa [Thu, 25 Aug 2016 18:53:06 +0000 (14:53 -0400)]
qemu: driver: Fix qemuDomainHelperGetVcpus for sparse vcpu topologies
ce43cca0e refactored the helper to prepare it for sparse topologies but
forgot to fix the iterator used to fill the structures. This would
result into a weirdly sparse populated array and possible out of bounds
access and crash once sparse vcpu topologies were allowed.
Peter Krempa [Thu, 25 Aug 2016 18:48:52 +0000 (14:48 -0400)]
virsh: vcpuinfo: Report vcpu number from the structure rather than it's position
virVcpuInfo contains the vcpu number that the data refers to. Report
what's returned by the daemon rather than the sequence number as with
sparse vcpu topologies they won't match.
Olga Krishtal [Thu, 18 Aug 2016 11:57:14 +0000 (14:57 +0300)]
vz: fixed race in vzDomainAttach/DettachDevice
While dettaching/attaching device in OpenStack, nova
calls vzDomainDettachDevice twice, because the update of the internal
configuration of the ct comes a bit latter than the update event.
As the result, we suffer from the second call to dettach the same device.
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
libvirt-python passes parameter bandwidth = 0
by default. This means that bandwidth is unlimited.
VZ driver doesn't support bandwidth rate limiting,
but we still need to handle it and fail if bandwidth > 0.
Signed-off-by: Pavel Glushchak <pglushchak@virtuozzo.com>
Laine Stump [Thu, 25 Aug 2016 05:46:37 +0000 (01:46 -0400)]
qemu: set tap device online for type='ethernet'
When support for auto-creating tap devices was added to <interface
type='ethernet'> in commit 9c17d6, the code assumed that
virNetDevTapCreate() would honor the VIR_NETDEV_TAP__CREATE_IFUP flag
that is supported by virNetDevTapCreateInBridgePort(). That isn't the
case - the latter function performs several operations, and one of
them is setting the tap device online. But virNetDevTapCreate() *only*
creates the tap device, and relies on the caller to do everything
else, so qemuInterfaceEthernetConnect() needs to call
virNetDevSetOnline() after the device is successfully created.
Laine Stump [Thu, 25 Aug 2016 05:18:25 +0000 (01:18 -0400)]
qemu: remove unnecessary setting of tap device online state
The linkstate setting of an <interface> is only meant to change the
online status reported to the guest system by the emulated network
device driver in qemu, but when support for auto-creating tap devices
for <interface type='ethernet'> was added in commit 9717d6, a chunk of
code was also added to qemuDomainChangeNetLinkState() that sets the
online status of the tap device (i.e. the *host* side of the
interface) for type='ethernet'. This was never done for tap devices
used in type='bridge' or type='network' interfaces, nor was it done in
the past for tap devices created by external scripts for
type='ethernet', so we shouldn't be doing it now.
This patch removes the bit of code in qemuDomainChangeNetLinkState()
that modifies online status of the tap device.
Vasiliy Tolstov [Wed, 24 Aug 2016 16:09:22 +0000 (19:09 +0300)]
qemu: fix ethernet network type ip/route assign
The call to virNetDevIPInfoAddToDev() that sets up tap device IP
addresses and routes was somehow incorrectly placed in
qemuInterfaceStopDevice() instead of qemuInterfaceStartDevice() in
commit fe8567f6. This fixes that error by moving the call to
virNetDevIPInfoAddToDev() to qemuInterfaceStartDevice().
Peter Krempa [Tue, 16 Aug 2016 13:02:11 +0000 (15:02 +0200)]
qemu: hotplug: Add support for VCPU unplug
This patch removes the old vcpu unplug code completely and replaces it
with the new code using device_del. The old hotplug code basically never
worked with any recent qemu and thus is useless.
As the new code is using device_del all the implications of using it
are present. Contrary to the device deletion code, the vcpu deletion
code fails if the unplug request is not executed in time.
Peter Krempa [Tue, 16 Aug 2016 12:44:26 +0000 (14:44 +0200)]
qemu: Use modern vcpu hotplug approach if possible
To allow unplugging the vcpus, hotplugging of vcpus on platforms which
require to plug multiple logical vcpus at once or plugging them in an
arbitrary order it's necessary to use the new device_add interface for
vcpu hotplug.
This patch adds support for the device_add interface using the old
setvcpus API by implementing an algorithm to select the appropriate
entities to plug in.
Peter Krempa [Thu, 4 Aug 2016 12:36:24 +0000 (14:36 +0200)]
qemu: command: Add support for sparse vcpu topologies
Add support for using the new approach to hotplug vcpus using device_add
during startup of qemu to allow sparse vcpu topologies.
There are a few limitations imposed by qemu on the supported
configuration:
- vcpu0 needs to be always present and not hotpluggable
- non-hotpluggable cpus need to be ordered at the beginning
- order of the vcpus needs to be unique for every single hotpluggable
entity
Qemu also doesn't really allow to query the information necessary to
start a VM with the vcpus directly on the commandline. Fortunately they
can be hotplugged during startup.
The new hotplug code uses the following approach:
- non-hotpluggable vcpus are counted and put to the -smp option
- qemu is started
- qemu is queried for the necessary information
- the configuration is checked
- the hotpluggable vcpus are hotplugged
- vcpus are started
This patch adds a lot of checking code and enables the support to
specify the individual vcpu element with qemu.
Peter Krempa [Thu, 4 Aug 2016 12:23:25 +0000 (14:23 +0200)]
qemu: process: Copy final vcpu order information into the vcpu definition
The vcpu order information is extracted only for hotpluggable entities,
while vcpu definitions belonging to the same hotpluggable entity need
to all share the order information.
We also can't overwrite it right away in the vcpu info detection code as
the order is necessary to add the hotpluggable vcpus enabled on boot in
the correct order.
The helper will store the order information in places where we are
certain that it's necessary.
Peter Krempa [Thu, 4 Aug 2016 11:57:46 +0000 (13:57 +0200)]
qemu: migration: Prepare for non-contiguous vcpu configurations
Introduce a new migration cookie flag that will be used for any
configurations that are not compatible with libvirt that would not
support the specific vcpu hotplug approach. This will make sure that old
libvirt does not fail to reproduce the configuration correctly.
The 'enabled' attribute allows to control the state of the vcpu.
'hotpluggable' controls whether given vcpu can be hotplugged and 'order'
allows to specify the order to add the vcpus.
Peter Krempa [Fri, 5 Aug 2016 12:48:27 +0000 (14:48 +0200)]
qemu: domain: Prepare for VCPUs vanishing while libvirt is not running
Similarly to devices the guest may allow unplug of the VCPU if libvirt
is down. To avoid problems, refresh the vcpu state on reconnect. Don't
mess with the vcpu state otherwise.
Peter Krempa [Sun, 31 Jul 2016 12:05:04 +0000 (14:05 +0200)]
qemu: domain: Extract cpu-hotplug related data
Now that the monitor code gathers all the data we can extract it to
relevant places either in the definition or the private data of a vcpu.
As only thread id is broken for TCG guests we may extract the rest of
the data and just skip assigning of the thread id. In case where qemu
would allow cpu hotplug in TCG mode this will make it work eventually.
Peter Krempa [Fri, 29 Jul 2016 17:24:22 +0000 (19:24 +0200)]
tests: cpu-hotplug: Add data for ppc64 platform including hotplug
Power 8 platform's basic hotpluggable unit is a core rather than a
thread for x86_64 family. This introduces most of the complexity of the
matching code and thus needs to be tested.
The test data contain data captured from in-order cpu hotplug and
unplug operations.
Peter Krempa [Tue, 23 Aug 2016 21:05:52 +0000 (17:05 -0400)]
tests: cpu-hotplug: Add data for x86 hotplug with 11+ vcpus
During review it was reported that adding at least 11 vcpus creates a
collision of prefixes in the monitor matching algorithm. Add a test case
to verify that the problem won't happen.
Peter Krempa [Fri, 29 Jul 2016 16:08:06 +0000 (18:08 +0200)]
tests: Add test infrastructure for qemuMonitorGetCPUInfo
As the combination algorithm is rather complex and ugly it's necessary
to make sure it works properly. Add test suite infrastructure for
testing it along with a basic test based on x86_64 platform.
Peter Krempa [Mon, 1 Aug 2016 11:56:23 +0000 (13:56 +0200)]
qemu: monitor: Add algorithm for combining query-(hotpluggable-)-cpus data
For hotplug purposes it's necessary to retrieve data using
query-hotpluggable-cpus while the old query-cpus API report thread IDs
and order of hotplug.
This patch adds code that merges the data using a rather non-trivial
algorithm and fills the data to the qemuMonitorCPUInfo structure for
adding to appropriate place in the domain definition.
Peter Krempa [Fri, 8 Jul 2016 11:52:11 +0000 (13:52 +0200)]
qemu: monitor: Add support for calling query-hotpluggable-cpus
Add support for retrieving information regarding hotpluggable cpu units
supported by qemu. Data returned by the command carries information
needed to figure out the granularity of hotplug, the necessary cpu type
name and the topology information.
Note that qemu doesn't specify any particular order of the entries thus
it's necessary sort them by socket_id, core_id and thread_id to the
order libvirt expects.
Peter Krempa [Thu, 28 Jul 2016 08:33:10 +0000 (10:33 +0200)]
qemu: monitor: Extract QOM path from query-cpus reply
To allow matching up the data returned by query-cpus to entries in the
query-hotpluggable-cpus reply for CPU hotplug it's necessary to extract
the QOM path as it's the only link between the two.
Peter Krempa [Fri, 29 Jul 2016 07:45:19 +0000 (09:45 +0200)]
qemu: capabilities: Extract availability of new cpu hotplug for machine types
QEMU reports whether 'query-hotpluggable-cpus' is supported for a given
machine type. Extract and cache the information using the capability
cache.
When copying the capabilities for a new start of qemu, mask out the
presence of QEMU_CAPS_QUERY_HOTPLUGGABLE_CPUS if the machine type
doesn't support hotpluggable cpus.
configuration where the maximum CPU count doesn't match the topology is
rejected. Prior to that only configurations where the topology would
contain more cpus than the maximum count would be rejected.
Use QEMU_CAPS_QUERY_HOTPLUGGABLE_CPUS as a relevant recent enough
witness to avoid breaking old configs.
Peter Krempa [Mon, 1 Aug 2016 11:44:25 +0000 (13:44 +0200)]
qemu: monitor: Return struct from qemuMonitor(Text|Json)QueryCPUs
Prepare to extract more data by returning an array of structs rather than
just an array of thread ids. Additionally report fatal errors separately
from qemu not being able to produce data.
Pino Toscano [Wed, 24 Aug 2016 14:14:24 +0000 (16:14 +0200)]
virsh: avoid i18n puzzle
Use the full versions of the message, instead of composing a base
message with what was updated; the change makes the messages properly
translatable, since different parts of a sentence might need different
declensions for example.
Pino Toscano [Wed, 24 Aug 2016 14:14:23 +0000 (16:14 +0200)]
virsh: respect -q/--quiet more
Turn various vshPrint() informative messages into vshPrintExtra(), so
they are not printed when requesting the quiet mode; neither XML/info
outputs nor the results of commands are affected.
Also change the expected outputs of the virsh-undefine test, since virsh
is invoked in quiet mode there.
Some informative messages might still be converted (and thus silenced
when in quiet mode), but this is an improvements nonetheless.
vzDomainMigrateConfirm3Params is whitelisted. Otherwise we need to
move removing domain from domain list from perform to confirm
step. This would further imply adding a flag and check that migration
is in progress to prohibit mistakenly (maliciously) removing domains
on confirm step. vz version of p2p also need to be fixed to include confirm step.
One would also need to add means to cleanup pending migration
on client disconnect as now is has state across several API
calls.
On the other hand current version of confirm step is totaly
harmless thus it is easier to whitelist it at the moment.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com> Signed-off-by: Maxim Nestratov <mnestratov@virtuozzo.com>
ACL check on perform step should be in API call itself to make ACL
checking script pass. Thus we need to reorganize code to obtain
domain object in perform API itself. Most of this is straight
forward, the only nuance is dropping locks on lengthy remote
operations.
The other motivation is to have only perform step ACL checks for
p2p migration instead of both begin in perform if we can leave
ACL check in vzDomainMigratePerformStep.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com>
The original motivation is to expand API calls like start/stop etc so that
the ACL checks could be added. But this patch has its own befenits.
1. functions like prlsdkStart/Stop use common routine to wait for
job without domain lock. They become more self contained and do
not return intermediate PRL_RESULT.
2. vzDomainManagedSave do not update cache twice.
Signed-off-by: Nikolay Shirokovskiy <nshirokovskiy@virtuozzo.com> Signed-off-by: Maxim Nestratov <mnestratov@virtuozzo.com>
Upon entry to qemuDomainAttachVirtioDiskDevice, src->encryption points
at a valid 'secret' buffer w/ nsecrets == 1; however, the call to
qemuDomainDetermineDiskChain will call virStorageFileGetMetadata
and eventually virStorageFileGetMetadataInternal where the src->encryption
was overwritten when probing the volume.
Commit id 'a48c7141' added code to virStorageFileGetMetadataInternal
to determine if the disk/volume would use/need encryption and allocated
a meta->encryption. This overwrote an existing encryption buffer
already provided by the XML
This patch adds a check for meta->encryption already present before
just allocating and overwriting an existing buffer. It then checks the
existing encryption data to ensure the XML provided format for the
disk matches the expected format read from the disk and errors if there
is a mismatch.
Laine Stump [Fri, 12 Aug 2016 02:28:27 +0000 (22:28 -0400)]
network: allow limiting a <forwarder> element to certain domains
For some unknown reason the original implementation of the <forwarder>
element only took advantage of part of the functionality in the
dnsmasq feature it exposes - it allowed specifying the ip address of a
DNS server which *all* DNS requests would be forwarded to, like this:
<forwarder addr='192.168.123.25'/>
This is a frontend for dnsmasq's "server" option, which also allows
you to specify a domain that must be matched in order for a request to
be forwarded to a particular server. This patch adds support for
specifying the domain. For example:
would forward requests for bob.example.com, ftp.example.com and
joe.corp.example.com all to the DNS server at 192.168.1.1, but would
forward requests for travesty.org and www.travesty.org to
10.0.0.1. And due to the second line, requests for www.example.com,
and odd.www.example.com would be resolved by the libvirt network's own
DNS server (i.e. thery wouldn't be immediately forwarded) even though
they also match 'example.com' - the match is given to the entry with
the longest matching domain. DNS requests not matching any of the
entries would be resolved by the libvirt network's own DNS server.
Laine Stump [Thu, 11 Aug 2016 21:29:43 +0000 (17:29 -0400)]
network: allow disabling dnsmasq's DNS server
If you define a libvirt virtual network with one or more IP addresses,
it starts up an instance of dnsmasq. It's always been possible to
avoid dnsmasq's dhcp server (simply don't include a <dhcp> element),
but until now it wasn't possible to avoid having the DNS server
listening; even if the network has no <dns> element, it is started
using default settings.
This patch adds a new attribute to <dns>: enable='yes|no'. For
backward compatibility, it defaults to 'yes', but if you don't want a
DNS server created for the network, you can simply add:
<dns enable='no'/>
to the network configuration, and next time the network is started
there will be no dns server created (if there is dhcp configuration,
dnsmasq will be started with "port=0" which disables the DNS server;
if there is no dhcp configuration, dnsmasq won't be started at all).
Laine Stump [Wed, 10 Aug 2016 23:09:55 +0000 (19:09 -0400)]
network: new network forward mode 'open'
The new forward mode 'open' is just like mode='route', except that no
firewall rules are added to assure that any traffic does or doesn't
pass. It is assumed that either they aren't necessary, or they will be
setup outside the scope of libvirt.
==18324== 32 bytes in 1 blocks are still reachable in loss record 41 of 114
==18324== at 0x4C2C070: calloc (vg_replace_malloc.c:623)
==18324== by 0x4EA479B: virAlloc (viralloc.c:144)
==18324== by 0x4EA674A: virBitmapNewQuiet (virbitmap.c:77)
==18324== by 0x4EA67F7: virBitmapNew (virbitmap.c:106)
==18324== by 0x4EC777D: dnsmasqCapsNewEmpty (virdnsmasq.c:801)
==18324== by 0x4EC781B: dnsmasqCapsNewFromBuffer (virdnsmasq.c:815)
==18324== by 0x407CF4: mymain (networkxml2conftest.c:99)
==18324== by 0x409CF0: virTestMain (testutils.c:982)
==18324== by 0x4080EA: main (networkxml2conftest.c:136)
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
This patch fixes a bug which occurs when we check a bus and unit number
for a new attached disk. We should do this check in ValidadionCallback,
not in PostParse callback. Because in PostParse we have not initialized
disk->info.addr.drive struct yet.
Move part of code from domainPostParseCallback to domainValidateCallback
and part from devicesPostParseCallback to deviceValidateCallback.
PostParse callbacks are for modification data.
ValidateCallbacks are only for checks.
Olga Krishtal [Thu, 18 Aug 2016 12:37:00 +0000 (15:37 +0300)]
vz: fixed race in vzDomainAttach/DettachDevice
While dettaching/attaching device in OpenStack, nova
calls vzDomainDettachDevice twice, because the update of the internal
configuration of the ct comes a bit latter than the update event.
As the result, we suffer from the second call to dettach the same device.
Signed-off-by: Olga Krishtal <okrishtal@virtuozzo.com>
Maxim Nestratov [Wed, 3 Aug 2016 09:41:53 +0000 (12:41 +0300)]
vz: reset errors after ignoring return values
If we are going to ignore return value of a functions
that can raise an error, it's not enough to use ignore_value
construction. We should explicitly call virResetLastError