Commit Graph

3044 Commits

Author SHA1 Message Date
Martin Kletzander
45ad1adb4a qemu: Reject unsupported tuning in session mode
When domain is started with setting that cannot be done, i.e. those
that require cgroups, there is no error reported and it succeeds
without any message whatsoever.

When setting with API, virsh, an error is reported, but only due to
the fact that no cgroups are mounted (priv->cgroup == NULL).

Given the above it seems reasonable to reject such unsupported
settings.

This patch effectively changes the error message from:

$ virsh -c qemu:///session schedinfo dummy
Scheduler      : Unknown
error: Requested operation is not valid: cgroup CPU controller is not mounted

to:

$ virsh -c qemu:///session schedinfo dummy
Scheduler      : Unknown
error: Operation not supported: CPU tuning is not available in session mode

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1023366

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-03-06 15:29:07 +01:00
Peter Krempa
3e04d65a07 qemu: monitor: Provide more information in generic block job error
The qemuMonitorJSONBlockJob handles a few errors internally. If qemu
returns a different error we would report a rather unhelpful message:

 $ virsh blockpull gluster-job vda --base /dev/null
 error: internal error: Unexpected error

As the actual message from qemu contains a bit more info, let's use it
to report something a little more useful:

 $ virsh blockpull gluster-job vda --base /dev/null
 error: internal error: Unexpected error: (GenericError) 'Base '/dev/null' not found'
2014-03-05 15:08:56 +01:00
Chunyan Liu
de6fa535b0 add 'driver' info to used_by
Specify which driver and which domain in used_by area to avoid conflict among
different drivers.

Signed-off-by: Chunyan Liu <cyliu@suse.com>
2014-03-04 12:24:13 +00:00
Peter Krempa
a31bd18f43 qemu: monitor: Fix error message and comment when getting cpu info
In qemuMonitorJSONExtractCPUInfo an error message hinted on missing
character device data which is wrong.

Also a comment states that only qemu-kvm tree includes the thread_id
field. This is no longer true.
2014-03-04 11:17:52 +01:00
Peter Krempa
d410e6f19d qemu: snapshot: Use better check when reverting external snapshots
https://bugzilla.redhat.com/show_bug.cgi?id=1071264

Reverting of external snapshots is not supported currently. The check
that is present doesn't properly check for all aspects that make a
snapshot external. Use virDomainSnapshotIsExternal() to do the check.
2014-03-04 11:12:44 +01:00
Michal Privoznik
042c4ab1c9 qemuBuildNicDevStr: Adapt to new advisory on multiqueue
As I did previously in 4f588a1b46, libvirt needs to set virtio vectors.
Previously, we were advised to use vectors=N, where

N = 2 * (number of queues) + 1

However, just recently this advisory has changed on the Multiquue wiki
page [1] to:

N = 2 * (number of queues) + 2

1: http://www.linux-kvm.org/page/Multiqueue#Enable_MQ_feature

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-03-04 10:43:05 +01:00
Eric Blake
b9dd878ff8 util: make it easier to grab only regular command exit
Auditing all callers of virCommandRun and virCommandWait that
passed a non-NULL pointer for exit status turned up some
interesting observations.  Many callers were merely passing
a pointer to avoid the overall command dying, but without
caring what the exit status was - but these callers would
be better off treating a child death by signal as an abnormal
exit.  Other callers were actually acting on the status, but
not all of them remembered to filter by WIFEXITED and convert
with WEXITSTATUS; depending on the platform, this can result
in a status being reported as 256 times too big.  And among
those that correctly parse the output, it gets rather verbose.
Finally, there were the callers that explicitly checked that
the status was 0, and gave their own message, but with fewer
details than what virCommand gives for free.

So the best idea is to move the complexity out of callers and
into virCommand - by default, we return the actual exit status
already cleaned through WEXITSTATUS and treat signals as a
failed command; but the few callers that care can ask for raw
status and act on it themselves.

* src/util/vircommand.h (virCommandRawStatus): New prototype.
* src/libvirt_private.syms (util/command.h): Export it.
* docs/internals/command.html.in: Document it.
* src/util/vircommand.c (virCommandRawStatus): New function.
(virCommandWait): Adjust semantics.
* tests/commandtest.c (test1): Test it.
* daemon/remote.c (remoteDispatchAuthPolkit): Adjust callers.
* src/access/viraccessdriverpolkit.c (virAccessDriverPolkitCheck):
Likewise.
* src/fdstream.c (virFDStreamCloseInt): Likewise.
* src/lxc/lxc_process.c (virLXCProcessStart): Likewise.
* src/qemu/qemu_command.c (qemuCreateInBridgePortWithHelper):
Likewise.
* src/xen/xen_driver.c (xenUnifiedXendProbe): Simplify.
* tests/reconnect.c (mymain): Likewise.
* tests/statstest.c (mymain): Likewise.
* src/bhyve/bhyve_process.c (virBhyveProcessStart)
(virBhyveProcessStop): Don't overwrite virCommand error.
* src/libvirt.c (virConnectAuthGainPolkit): Likewise.
* src/openvz/openvz_driver.c (openvzDomainGetBarrierLimit)
(openvzDomainSetBarrierLimit): Likewise.
* src/util/virebtables.c (virEbTablesOnceInit): Likewise.
* src/util/viriptables.c (virIpTablesOnceInit): Likewise.
* src/util/virnetdevveth.c (virNetDevVethCreate): Fix debug
message.
* src/qemu/qemu_capabilities.c (virQEMUCapsInitQMP): Add comment.
* src/storage/storage_backend_iscsi.c
(virStorageBackendISCSINodeUpdate): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-03-03 12:40:32 -07:00
Daniel P. Berrange
36ff4ed1ec Generate a unique journald log for QEMU capabilities failure
When probing QEMU capabilities fails for a binary generate a
log message with MESSAGE_ID==8ae2f3fb-2dbe-498e-8fbd-012d40afa361.

This can be directly queried from journald based on the UUID
instead of needing string grep. This lets tools like libguestfs'
bug reporting tool trivially do automated sanity tests on the
host they're running on.

 $ journalctl MESSAGE_ID=8ae2f3fb-2dbe-498e-8fbd-012d40afa361
 Feb 21 17:11:01 localhost.localdomain lt-libvirtd[9196]:
 Failed to probe capabilities for /bin/qemu-system-alpha:
 internal error: Child process (LC_ALL=C LD_LIBRARY_PATH=
 /home/berrange/src/virt/libvirt/src/.libs PATH=/usr/lib64/
 ccache:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:
 /usr/bin:/root/bin HOME=/root USER=root LOGNAME=root
 /bin/qemu-system-alpha -help) unexpected exit status 127:
 /bin/qemu-system-alpha: error while loading shared libraries:
 libglapi.so.0: cannot open shared object file: No such file
 or directory

 $ journalctl MESSAGE_ID=8ae2f3fb-2dbe-498e-8fbd-012d40afa361 --output=json
 { ...snip...
  "LIBVIRT_SOURCE" : "file",
  "PRIORITY" : "3",
  "CODE_FILE" : "qemu/qemu_capabilities.c",
  "CODE_LINE" : "2770",
  "CODE_FUNC" : "virQEMUCapsLogProbeFailure",
  "MESSAGE_ID" : "8ae2f3fb-2dbe-498e-8fbd-012d40afa361",
  "LIBVIRT_QEMU_BINARY" : "/bin/qemu-system-xtensa",
  "MESSAGE" : "Failed to probe capabilities for /bin/qemu-system-xtensa:
   internal error: Child process (LC_ALL=C LD_LIBRARY_PATH=/home/berrange
   /src/virt/libvirt/src/.libs PATH=/usr/lib64/ccache:/usr/local/sbin:
   /usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin HOME=/root
   USER=root LOGNAME=root /bin/qemu-system-xtensa -help) unexpected
   exit status 127: /bin/qemu-system-xtensa: error while loading shared
   libraries: libglapi.so.0: cannot open shared object file: No such
    file or directory\n" }

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-03-03 11:42:37 +00:00
Michal Privoznik
1df00e2b22 virDomainBlockStats(Flags): Produce saner error message on empty disk path
As of 0bd2ccdec an empty disk path for virDomainBlockStats (or the one
with Flags) is allowed meaning "get me overall summarized statistics".
However, running 'virsh domblkstat $dom' throws a misleading error:

  # ./tools/virsh domblkstat dom
  error: Failed to get block stats dom
  error: invalid argument: invalid path:

while after this commit

  # virsh domblkstat dom
  error: Operation not supported: summary statistics are not supported yet

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-28 09:50:01 +01:00
Eric Blake
60f7303c15 qemu: adjust maxmem/maxvcpu computation
https://bugzilla.redhat.com/show_bug.cgi?id=1038363

If a domain has a different maximum for persistent and live maxmem
or max vcpus, then it is possible to hit cases where libvirt
refuses to adjust the current values or gets halfway through
the adjustment before failing.  Better is to determine up front
if the change is possible for all requested flags.

Based on an idea by Geoff Franks.

* src/qemu/qemu_driver.c (qemuDomainSetMemoryFlags): Compute
correct maximum if both live and config are being set.
(qemuDomainSetVcpusFlags): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-02-20 11:27:16 -07:00
Thorsten Behrens
65158899b7 Make qemuGetDomainTotalCPUStats a virCgroup function.
To reuse this from other drivers, like lxc.
2014-02-20 16:20:09 +01:00
Oleg Strikov
41b9b71877 qemu: Use virtio network device for aarch64/virt
This patch changes network device type used by default from rtl8139
to virtio when architecture type is aarch64 and machine type is virt.
Qemu doesn't support any other machine types for aarch64 right now and
we can't make any other aarch64-specific tuning in this function yet.

Signed-off-by: Oleg Strikov <oleg.strikov@canonical.com>
2014-02-19 10:46:10 -05:00
Li Zhang
cffa51b81d Add a default USB keyboard and USB mouse for PPC64
There is no keyboard working on PPC64 and PS2 mouse is only for X86
when graphics are enabled.

Add a USB keyboard and USB mouse for PPC64 when graphics are enabled.

Signed-off-by: Li Zhang <zhlcindy@linux.vnet.ibm.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2014-02-19 09:16:31 +01:00
Li Zhang
78730478aa qemu: format qemu command line for USB keyboard
Format qemu command line for USB keyboard
and add test cases for it.

Signed-off-by: Li Zhang <zhlcindy@linux.vnet.ibm.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2014-02-19 09:16:31 +01:00
Li Zhang
f5ffd45f4c qemu: Add USB keyboard capability
Add USB keyboard capability probing and test cases.

Signed-off-by: Li Zhang <zhlcindy@linux.vnet.ibm.com>
Signed-off-by: Ján Tomko <jtomko@redhat.com>
2014-02-19 09:16:31 +01:00
Michal Privoznik
f1ab06e43d network: Introduce network hooks
There might be some use cases, where user wants to prepare the host or
its environment prior to starting a network and do some cleanup after
the network has been shut down. Consider all the functionality that
libvirt doesn't currently have as an example what a hook script can
possibly do.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-18 14:46:49 +01:00
Michal Privoznik
3b2c279449 qemu: Implement VIR_DOMAIN_TAINT_HOOK
Currently, there's just one place where we care if hook script is
changing the domain XML: migration hook for incoming migration. In
all other places where a hook script is executed, we don't read the
XML back from the script.

Anyway, the hook script can alter domain XML and hence we should taint
it if the script did.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-17 11:38:15 +01:00
Peter Krempa
3cf074ee40 qemu: snapshot: Add support for external active snapshots on gluster
Add support for gluster backed images as sources for snapshots in the
qemu driver. This will also simplify adding further network backed
volumes as sources for snapshot in case qemu will support them.
2014-02-14 11:07:29 +01:00
Peter Krempa
7183d7d2e8 qemu: snapshot: Use new APIs to detect presence of existing storage files
Use the new storage driver based "stat" api to detect exiting files just
as we did with local files.
2014-02-14 11:07:29 +01:00
Peter Krempa
8f4091d677 qemu: Switch snapshot deletion to the new API functions
Use the new storage driver APIs to delete snapshot backing files in case
of failure instead of directly relying on "unlink". This will help us in
the future when we will be adding network based storage without local
representation in the host.
2014-02-14 11:07:29 +01:00
Peter Krempa
6fb5a397bf conf: Move qemuSnapshotDiskGetActualType to virDomainSnapshotDiskGetActualType
All the data for getting the actual type is present in the snapshot
config. There is no need to have this function private to the qemu
driver and it will be re-used later in other parts of libvirt
2014-02-14 10:47:56 +01:00
Peter Krempa
f8f020da0a conf: Move qemuDiskGetActualType to virDomainDiskGetActualType
All the data for getting the actual type is present in the domain
config. There is no need to have this function private to the qemu
driver and it will be re-used later in other parts of libvirt
2014-02-14 10:47:56 +01:00
Pradipta Kr. Banerjee
cd921cf077 Handle non-sequential NUMA node numbers
On some platforms like IBM PowerNV the NUMA node numbers can be
non-sequential. For eg. numactl --hardware o/p from such a machine looks
as given below

node distances:
   node   0   1  16  17
     0:  10  40  40  40
     1:  40  10  40  40
    16:  40  40  10  40
    17:  40  40  40  10

The NUMA nodes are 0,1,16,17

Libvirt uses sequential index as NUMA node numbers and this can
result in crash or incorrect results.

Signed-off-by: Shivaprasad G Bhat <sbhat@linux.vnet.ibm.com>
Signed-off-by: Pradipta Kr. Banerjee <bpradip@in.ibm.com>
2014-02-11 14:44:20 +00:00
Martin Kletzander
d27e6bc40f qemu: introduce spiceport chardev backend
Add a new backend for any character device.  This backend uses channel
in spice connection.  This channel is similar to spicevmc, but
all-purpose in contrast to spicevmc.

Apart from spicevmc, spiceport-backed chardev will not be formatted
into the command-line if there is no spice to use (with test for that
as well).  For this I moved the def->graphics counting to the start
of the function so its results can be used in rest of the code even in
the future.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-02-11 13:43:55 +01:00
Martin Kletzander
296a4791eb qemu: remove pointless condition
This patch is here just to ease the code review and make related
changes look more sensible.  Apart from removing the condition this is
merely a whitespace (indentation) change.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-02-11 13:43:55 +01:00
Martin Kletzander
a53e504052 qemu: rework '-serial none'
Limiting ourselves to qemu without QEMU_CAPS_DEVICE capability, we
used '-serial none' only if there was no serial device defined in the
domain XML.  This means that if we want to have a possibility of the
device being defined in XML, but not used in the command-line
(e.g. when it's pointless), we'll fail to attach '-serial none' to the
command-line (when skipping the device's command-line building and the
device being the only one).

Since there is no such device, this patch doesn't actually do
anything, but enables easier future additions in this manner.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-02-11 13:43:55 +01:00
Martin Kletzander
5b189541ac conf: introduce spiceport chardev backend
Add a new character device backend called 'spiceport' that uses
spice's channel for communications and apart from spicevmc can be used
as a backend for any character device from libvirt's point of view.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-02-11 13:43:55 +01:00
Peter Krempa
9bf629ab60 qemu: Use correct permissions when determining the image chain
The code took into account only the global permissions. The domains now
support per-vm DAC labels and per-image DAC labels. Use the most
specific label available.
2014-02-10 15:49:59 +01:00
Peter Krempa
600bca592b qemu: hyperv: Add support for timer enlightenments
Add a new <timer> for the HyperV reference time counter enlightenment
and the iTSC reference page for Windows guests.

This feature provides a paravirtual approach to track timer events for
the guest (similar to kvmclock) with the option to use real hardware
clock on systems with a iTSC with compensation across various hosts.
2014-02-10 11:30:10 +01:00
Peter Krempa
8ffaa42d7b conf: Enforce supported options for certain timers
According to the documentation various timer options are only supported
by certain timer types. Add a post parse check to verify that the user
didn't specify invalid options.

Also fix the qemu command line parsing function to set correct default
values for the kvmclock timer so that it passes the new check.
2014-02-10 11:17:32 +01:00
Martin Kletzander
440a1aa508 qemu: keep pre-migration domain state after failed migration
Couple of codepaths shared the same code which can be moved out to a
function and on one of such places, qemuMigrationConfirmPhase(), the
domain was resumed even if it wasn't running before the migration
started.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1057407

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-02-07 10:07:38 +01:00
Matthieu Coudron
0778fc1ab9 qemu_driver: Introduce <filesystem/> support in device attach/detach
This commit allows to attach/detach a <filesystem> device in qemu. For
this purpose I'm introducing two new functions: virDomainFSInsert() and
virDomainFSRemove() and adding necessary code in the qemu driver.  It
compares filesystems based on their "destination" folder. So if two
filesystems share the same destination, they are considered equal and
the qemu driver would reject the insertion.

Signed-off-by: Matthieu Coudron <mattator@gmail.com>
2014-02-06 17:20:03 +01:00
Jiri Denemark
05bf937572 qemu: Fix crash in virDomainMemoryStats with old qemu
If virDomainMemoryStats was run on a domain with virtio balloon driver
running on an old qemu which supports QMP but does not support qom-list
QMP command, libvirtd would crash. The reason is we did not check if
qemuMonitorJSONGetObjectListPaths failed and moreover we even stored its
result in an unsigned integer type.
2014-02-06 11:29:29 +01:00
Peter Krempa
5d2691cc4c qemu: blockjob: Print correct file name in error message
When attempting a blockcommit from the top layer, the base argument
passed is NULL. This will be dereferenced when attempting a commit with
an empty image chain. Output the real volume path instead:

virsh blockcommit --verbose --path vda --domain DOMNAME --wait
error: invalid argument: top '/path/somefile' in chain for 'vda' has no backing file

instead of:

error: invalid argument: top '(null)' in chain for 'vda' has no backing file
2014-02-06 10:43:57 +01:00
Michal Privoznik
51bea5df5d qemuBuildClockArgStr: Allow localtime clock basis
https://bugzilla.redhat.com/show_bug.cgi?id=1046192

Commit b8bf79a, which adds clock='variable', forgets to check
localtime basis in qemuBuildClockArgStr(). So that localtime
basis could not be used.

Reported-by: Jincheng Miao <jmiao@redhat.com>
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
2014-02-06 07:51:07 +01:00
Eric Blake
f34ea654de maint: fix grammar in conf file
Noticed a misuse of 'to' while testing my event regression under
polkit ACLs, and decided to review the entire conf files for
other legibility bugs.

* daemon/libvirtd.conf: Use correct grammar.
* src/qemu/qemu.conf: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-02-05 10:40:14 -07:00
Eric Blake
11f20e43f1 event: move event filtering to daemon (regression fix)
https://bugzilla.redhat.com/show_bug.cgi?id=1058839

Commit f9f56340 for CVE-2014-0028 almost had the right idea - we
need to check the ACL rules to filter which events to send.  But
it overlooked one thing: the event dispatch queue is running in
the main loop thread, and therefore does not normally have a
current virIdentityPtr.  But filter checks can be based on current
identity, so when libvirtd.conf contains access_drivers=["polkit"],
we ended up rejecting access for EVERY event due to failure to
look up the current identity, even if it should have been allowed.

Furthermore, even for events that are triggered by API calls, it
is important to remember that the point of events is that they can
be copied across multiple connections, which may have separate
identities and permissions.  So even if events were dispatched
from a context where we have an identity, we must change to the
correct identity of the connection that will be receiving the
event, rather than basing a decision on the context that triggered
the event, when deciding whether to filter an event to a
particular connection.

If there were an easy way to get from virConnectPtr to the
appropriate virIdentityPtr, then object_event.c could adjust the
identity prior to checking whether to dispatch an event.  But
setting up that back-reference is a bit invasive.  Instead, it
is easier to delay the filtering check until lower down the
stack, at the point where we have direct access to the RPC
client object that owns an identity.  As such, this patch ends
up reverting a large portion of the framework of commit f9f56340.
We also have to teach 'make check' to special-case the fact that
the event registration filtering is done at the point of dispatch,
rather than the point of registration.  Note that even though we
don't actually use virConnectDomainEventRegisterCheckACL (because
the RegisterAny variant is sufficient), we still generate the
function for the purposes of documenting that the filtering
takes place.

Also note that I did not entirely delete the notion of a filter
from object_event.c; I still plan on using that for my upcoming
patch series for qemu monitor events in libvirt-qemu.so.  In
other words, while this patch changes ACL filtering to live in
remote.c and therefore we have no current client of the filtering
in object_event.c, the notion of filtering in object_event.c is
still useful down the road.

* src/check-aclrules.pl: Exempt event registration from having to
pass checkACL filter down call stack.
* daemon/remote.c (remoteRelayDomainEventCheckACL)
(remoteRelayNetworkEventCheckACL): New functions.
(remoteRelay*Event*): Use new functions.
* src/conf/domain_event.h (virDomainEventStateRegister)
(virDomainEventStateRegisterID): Drop unused parameter.
* src/conf/network_event.h (virNetworkEventStateRegisterID):
Likewise.
* src/conf/domain_event.c (virDomainEventFilter): Delete unused
function.
* src/conf/network_event.c (virNetworkEventFilter): Likewise.
* src/libxl/libxl_driver.c: Adjust caller.
* src/lxc/lxc_driver.c: Likewise.
* src/network/bridge_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/remote/remote_driver.c: Likewise.
* src/test/test_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/vbox/vbox_tmpl.c: Likewise.
* src/xen/xen_driver.c: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-02-05 08:03:31 -07:00
Laine Stump
0d0a7bf45a qemu: be sure we're using the updated value of backend during hotplug
commit f094aaac changed qemuPrepareHostdevPCIDevices() such that it
may modify the "backend" (vfio vs. legacy kvm) setting in the
virHostdevDef. However, qemuDomainAttachHostPciDevice() (used by
hotplug) copies the backend setting into a local *before* calling
qemuPrepareHostdevPCIDevices(), and then later makes a decision based
on that pre-change value.

The result is that, if the backend had been set to "default" (i.e. not
specified in the config) and was later updated to "VFIO" by
qemuPrepareHostdevPCIDevices(), the qemu process' MacMemLock is not
increased (as is required for VFIO device assignment).

This patch delays making the local copy of backend until after its
potential modification.
2014-02-04 14:05:09 +02:00
Martin Kletzander
b44f9e7ec9 spice: don't force user to specify spicevmc channel
We support only one spicevmc channel name anyway and the code is
prepared to use the default one, there's only one check missing.  It
is also mentioned in the documentation already and helps defining
domains with spice vdagent for people using virsh.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
2014-02-03 09:46:47 +01:00
Daniel P. Berrange
6e5c79a1b5 Push nwfilter update locking up to top level
The NWFilter code has as a deadlock race condition between
the virNWFilter{Define,Undefine} APIs and starting of guest
VMs due to mis-matched lock ordering.

In the virNWFilter{Define,Undefine} codepaths the lock ordering
is

  1. nwfilter driver lock
  2. virt driver lock
  3. nwfilter update lock
  4. domain object lock

In the VM guest startup paths the lock ordering is

  1. virt driver lock
  2. domain object lock
  3. nwfilter update lock

As can be seen the domain object and nwfilter update locks are
not acquired in a consistent order.

The fix used is to push the nwfilter update lock upto the top
level resulting in a lock ordering for virNWFilter{Define,Undefine}
of

  1. nwfilter driver lock
  2. nwfilter update lock
  3. virt driver lock
  4. domain object lock

and VM start using

  1. nwfilter update lock
  2. virt driver lock
  3. domain object lock

This has the effect of serializing VM startup once again, even if
no nwfilters are applied to the guest. There is also the possibility
of deadlock due to a call graph loop via virNWFilterInstantiate
and virNWFilterInstantiateFilterLate.

These two problems mean the lock must be turned into a read/write
lock instead of a plain mutex at the same time. The lock is used to
serialize changes to the "driver->nwfilters" hash, so the write lock
only needs to be held by the define/undefine methods. All other
methods can rely on a read lock which allows good concurrency.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2014-01-30 18:00:20 +00:00
Osier Yang
f406aa25f2 qemu: Fix the error message for scsi host device's shareable checking
This fixes the wrong argument order.
2014-01-30 16:50:10 +08:00
Osier Yang
10c9ceff6d util: Add one argument for several scsi utils
To support passing the path of the test data to the utils, one
more argument is added to virSCSIDeviceGetSgName,
virSCSIDeviceGetDevName, and virSCSIDeviceNew, and the related
code is changed accordingly.

Later tests for the scsi utils will be based on this patch.

Signed-off-by: Osier Yang <jyang@redhat.com>
2014-01-30 15:48:28 +08:00
Osier Yang
fd243fc4ad qemu: Don't fail if the SCSI host device is shareable between domains
It doesn't make sense to fail if the SCSI host device is specified
as "shareable" explicitly between domains (NB, it works if and only
if the device is specified as "shareable" for *all* domains,
otherwise it fails).

To fix the problem, this patch introduces an array for virSCSIDevice
struct, which records all the names of domain which are using the
device (note that the recorded domains must specify the device as
shareable).  And the change on the data struct brings on many
subsequent changes in the code.

Prior to this patch, the "shareable" tag didn't work as expected,
it actually work like "non-shareable".  So this patch also added notes
in formatdomain.html to declare the fact.

* src/util/virscsi.h:
  - Remove virSCSIDeviceGetUsedBy
  - Change definition of virSCSIDeviceGetUsedBy and virSCSIDeviceListDel
  - Add virSCSIDeviceIsAvailable

* src/util/virscsi.c:
  - struct virSCSIDevice: Change "used_by" to be an array; Add
    "n_used_by" as the array count
  - virSCSIDeviceGetUsedBy: Removed
  - virSCSIDeviceFree: frees the "used_by" array
  - virSCSIDeviceSetUsedBy: Copy the domain name to avoid potential
    memory corruption
  - virSCSIDeviceIsAvailable: New
  - virSCSIDeviceListDel: Change the logic, for device which is already
    in the list, just remove the corresponding entry in "used_by". And
    since it's only used in one place, we can safely removing the code
    to find out the dev in the list first.
  - Copyright updating

* src/libvirt_private.sys:
  - virSCSIDeviceGetUsedBy: Remove
  - virSCSIDeviceIsAvailable: New

* src/qemu/qemu_hostdev.c:
  - qemuUpdateActiveScsiHostdevs: Check if the device existing before
    adding it to the list;
  - qemuPrepareHostdevSCSIDevices: Error out if the not all domains
    use the device as "shareable"; Also don't try to add the device
    to the activeScsiHostdevs list if it already there; And make
    more sensible error w.r.t the current "shareable" value in
    driver->activeScsiHostdevs.
  - qemuDomainReAttachHostScsiDevices: Change the logic according
    to the changes on helpers.

Signed-off-by: Osier Yang <jyang@redhat.com>
2014-01-30 15:46:24 +08:00
Peter Krempa
7076b4b72c snapshot: Add support for specifying snapshot disk backing type
Add support for specifying various types when doing snapshots. This will
later allow to do snapshots on network backed volumes. Disks of type
'volume' are not supported by snapshots (yet).

Also amend the test suite to check parsing of the various new disk
types that can now be specified.
2014-01-29 12:56:35 +01:00
Pradipta Kr. Banerjee
c6320d3463 Add hw random number generator (/dev/hwrng) to cgroup ACL
Creating a qemu VM with /dev/hwrng as backend RNG device throws the
following error - "Could not open '/dev/hwrng': Permission denied"
This patch fixes the issue

Signed-off-by: Pradipta Kr. Banerjee <bpradip@in.ibm.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-27 09:48:39 -07:00
John Ferlan
46a0737e13 Block info query: Add check for transient domain
Currently the qemuDomainGetBlockInfo will return allocation == physical
for most backing stores. For a qcow2 block backed device it's possible
to return the highest lv extent allocated from qemu for an active guest.
That is a value where allocation != physical and one would hope be less.
However, if the guest is not running, then the code falls back to returning
allocation == physical. This turns out to be problematic for rhev which
monitors the size of the backing store. During a migration, before the
VM has been started on the target and while it is deemed inactive on the
source, there's a small window of time where the allocation is returned
as physical triggering the code to extend the file unnecessarily.

Since rhev uses transient domains and this is edge condition for a transient
domain, rather than returning good status and allocation == physical when
this "window of opportunity" exists, this patch will check for a transient
(or non persistent) domain and return a failure to the caller rather than
returning the defaults. For a persistent domain, the defaults will be
returned. The description for the virDomainGetBlockInfo has been updated
to describe the phenomena.
2014-01-24 11:37:18 -05:00
Gao feng
71f7d5840f qemu: remove memset params array to zero in qemuDomainGetPercpuStats
the array params is allocated by VIR_ALLOC_N in
remoteDispatchDomainGetCPUStats. it had been set
to zero. No need to reset it to zero again, and
this reset here is incorrect too, nparams * ncpus
is the array length not the size of params array.

Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
2014-01-24 16:31:53 +08:00
Osier Yang
2b66504ded util: Add "shareable" field for virSCSIDevice struct
Unlike the host devices of other types, SCSI host device XML supports
"shareable" tag. This patch introduces it for the virSCSIDevice struct
for a later patch use (to detect if the SCSI device is shareable when
preparing the SCSI host device in QEMU driver).
2014-01-23 17:52:33 +08:00
Eric Blake
7f2d27d1e3 api: require write permission for guest agent interaction
I noticed that we allow virDomainGetVcpusFlags even for read-only
connections, but that with a flag, it can require guest agent
interaction.  It is feasible that a malicious guest could
intentionally abuse the replies it sends over the guest agent
connection to possibly trigger a bug in libvirt's JSON parser,
or withhold an answer so as to prevent the use of the agent
in a later command such as a shutdown request.  Although we
don't know of any such exploits now (and therefore don't mind
posting this patch publicly without trying to get a CVE assigned),
it is better to err on the side of caution and explicitly require
full access to any domain where the API requires guest interaction
to operate correctly.

I audited all commands that are marked as conditionally using a
guest agent.  Note that at least virDomainFSTrim is documented
as needing a guest agent, but that such use is unconditional
depending on the hypervisor (so the existing domain:fs_trim ACL
should be sufficient there, rather than also requirng domain:write).
But when designing future APIs, such as the plans for obtaining
a domain's IP addresses, we should copy the approach of this patch
in making interaction with the guest be specified via a flag, and
use that flag to also require stricter access checks.

* src/libvirt.c (virDomainGetVcpusFlags): Forbid guest interaction
on read-only connection.
(virDomainShutdownFlags, virDomainReboot): Improve docs on agent
interaction.
* src/remote/remote_protocol.x
(REMOTE_PROC_DOMAIN_SNAPSHOT_CREATE_XML)
(REMOTE_PROC_DOMAIN_SET_VCPUS_FLAGS)
(REMOTE_PROC_DOMAIN_GET_VCPUS_FLAGS, REMOTE_PROC_DOMAIN_REBOOT)
(REMOTE_PROC_DOMAIN_SHUTDOWN_FLAGS): Require domain:write for any
conditional use of a guest agent.
* src/xen/xen_driver.c: Fix clients.
* src/libxl/libxl_driver.c: Likewise.
* src/uml/uml_driver.c: Likewise.
* src/qemu/qemu_driver.c: Likewise.
* src/lxc/lxc_driver.c: Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
2014-01-22 16:52:41 -07:00
Peter Krempa
7f0fd42741 qemu: Avoid crash in qemuDiskGetActualType
Libvirtd would crash if a domain contained an empty cdrom drive of
type='volume' as the disk def->srcpool member would be dereferenced. Fix
it by checking if the source pool is present before dereferencing it.

Also alter tests to catch this issue in the future.

Reported by: Kevin Shanahan
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1056328
2014-01-22 11:33:31 +01:00