John Ferlan reported the following Coverity warning:
In libxlDomainCoreDump() Coverity has noted a FORWARD_NULL reference:
2004 if ((flags & VIR_DUMP_CRASH) && !vm->persistent) {
2005 virDomainObjListRemove(driver->domains, vm);
(20) Event assign_zero: Assigning: "vm" = "NULL".
Also see events: [var_deref_model]
2006 vm = NULL;
2007 }
2008
2009 ret = 0;
2010
2011 cleanup_unpause:
(21) Event var_deref_model: Passing null pointer "vm" to function
"virDomainObjIsActive(virDomainObjPtr)", which dereferences it. [details]
Also see events: [assign_zero]
2012 if (virDomainObjIsActive(vm) && paused) {
2013 if (libxl_domain_unpause(priv->ctx, dom->id) != 0) {
2014 virReportError(VIR_ERR_INTERNAL_ERROR,
Removing the vm from domain obj list and setting it to NULL can be
done in the previous 'if (flags & VIR_DUMP_CRASH)' conditional. Fix
the Coverity warning by ensuring vm is not NULL before testing if it
is still active.
Now that most fields of libxlDriverPrivate struct are immutable
or self-locking, there is no need to acquire the driver lock in
much of the libxl driver.
The libxlDriverPrivate struct contains an variety of data with
varying access needs. Similar to the QEMU and LXC drivers,
move all the static config data into a dedicated libxlDriverConfig
object. The only locking requirement is to hold the driver lock
while obtaining an instance of libxlDriverConfig. Once a reference
is held on the config object, it can be used completely lockless
since it is immutable.
libxlDomainGetInfo() uses the driver-wide libxl ctx when
it would be more appropriate to use the per-domain ctx
associated with the domain. Switch to using the per-domain
libxl ctx.
libxlMakeDomCreateInfo() uses the driver-wide libxl ctx when
it would be more appropriate to use the per-domain ctx
associated with the domain. Switch to using the per-domain
libxl ctx.
libxl version info is static data as far as the libxl driver
is concerned, so retrieve this info when the driver is initialized
and stash it in the libxlDriverPrivate object. Subsequently use
the stashed info instead of repeatedly calling libxl_get_version_info().
Detect early on in libxl driver initialization if the driver
should be loaded at all, avoiding needless initialization steps
that only have to be undone later. While at it, move the
detection to a helper function to improve readability.
After detecting that the driver should be loaded, subsequent
failures such as initializing the log stream, allocating libxl
ctx, etc. should be treated as failure to initialize the driver.
Create libxl_domain.[ch] and move all functions operating on
libxlDomainObjPrivate to these files. This will be useful for
future patches that e.g. add job support for libxlDomainObjPrivate.
More fallout from commit d72ef888. When reconnecting to running
domains, the libxl_ctx in libxlDomainObjPrivate was used before
initializing it, causing a segfault in libxl and consequently
crashing libvirtd.
Initialize the libxlDomainObjPrivate libxl_ctx in libxlReconnectDomain,
and while at it use this ctx in libxlReconnectDomain instead of the
driver-wide ctx.
If we reached cleanup: prior to allocating cpus, it was possible that
'nr_nodes' had a value, but cpus was NULL leading to a possible NULL
deref. Add a 'cpus' as an end condition to for loop
From: Dario Faggioli <dario.faggioli@citrix.com>
Starting from Xen 4.2, libxl has all the bits and pieces in place
for retrieving an adequate amount of information about the host
NUMA topology. It is therefore possible, after a bit of shuffling,
to arrange those information in the way libvirt wants to present
them to the outside world.
Therefore, with this patch, the <topology> section of the host
capabilities is properly populated, when running on Xen, so that
we can figure out whether or not we're running on a NUMA host,
and what its characteristics are.
[raistlin@Zhaman ~]$ sudo virsh --connect xen:/// capabilities
<capabilities>
<host>
<cpu>
....
<topology>
<cells num='2'>
<cell id='0'>
<memory unit='KiB'>6291456</memory>
<cpus num='8'>
<cpu id='0' socket_id='1' core_id='0' siblings='0-1'/>
<cpu id='1' socket_id='1' core_id='0' siblings='0-1'/>
<cpu id='2' socket_id='1' core_id='1' siblings='2-3'/>
<cpu id='3' socket_id='1' core_id='1' siblings='2-3'/>
<cpu id='4' socket_id='1' core_id='9' siblings='4-5'/>
<cpu id='5' socket_id='1' core_id='9' siblings='4-5'/>
<cpu id='6' socket_id='1' core_id='10' siblings='6-7'/>
<cpu id='7' socket_id='1' core_id='10' siblings='6-7'/>
</cpus>
</cell>
<cell id='1'>
<memory unit='KiB'>6881280</memory>
<cpus num='8'>
<cpu id='8' socket_id='0' core_id='0' siblings='8-9'/>
<cpu id='9' socket_id='0' core_id='0' siblings='8-9'/>
<cpu id='10' socket_id='0' core_id='1' siblings='10-11'/>
<cpu id='11' socket_id='0' core_id='1' siblings='10-11'/>
<cpu id='12' socket_id='0' core_id='9' siblings='12-13'/>
<cpu id='13' socket_id='0' core_id='9' siblings='12-13'/>
<cpu id='14' socket_id='0' core_id='10' siblings='14-15'/>
<cpu id='15' socket_id='0' core_id='10' siblings='14-15'/>
</cpus>
</cell>
</cells>
</topology>
</host>
....
Cleanup the libxl capabilities code to be a bit more extensible,
splitting out the creation of host and guest capabilities. This
should make it easier to implement additional capabilities in the
future, such as NUMA topology reporting.
There is a potential leak of a newly created libxlDomainObjPrivate
when subsequent allocation of the object's chrdev field fails.
Unref the object on such an error so that it is properly disposed.
Commit d72ef888 introduced a bug in the libxl driver that will
segfault libvirtd if libxl reports an error message, e.g. when
attempting to initialize the driver on a non-Xen system. I
assumed it was valid to pass a NULL logger to libxl_ctx_alloc(),
but that is not the case since any errors associated with the ctx
that are emitted by libxl will dereference the logger and crash
libvirtd.
Errors associated with the libxl driver-wide ctx could be useful
for debugging anyway, so create a 'libxl-driver.log' to capture
these errors.
introduced by cs 4b9eec50fe ("libxl: implement per
NUMA node free memory reporting"). What was wrong was that
libxl_get_numainfo() put in nr_nodes the actual number of
host NUMA nodes, not the highest node ID (like libnuma's
numa_max_node() does instead).
While at it, turn the failure of libxl_get_numainfo() from
a simple warning to a proper error, as requested during the
review of another patch of the original series.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Daniel P. Berrange <berrange@redhat.com>
Currently, only one log file is created by the libxl driver, with
all output from libxl for all domains going to this one file.
Create a per-domain log file based on domain name, making sifting
through the logs a bit easier. This required deferring libxl_ctx
allocation until starting the domain, which is fine since the
ctx is not used when the domain is inactive.
Tested-by: Dario Faggioli <dario.faggioli@citrix.com>
this patch introduce the console api in libxl driver for both pv and
hvm guest. and import and update the libxlMakeChrdevStr function
which was deleted in commit dfa1e1dd.
Signed-off-by: Bamvor Jian Zhang <bjzhang@suse.com>
The avail_vcpu bitmap has to be allocated before it can be used (using
the maximum allowed value for that). Then for each available VCPU the
bit in the mask has to be set (libxl_bitmap_set takes a bit position
as an argument, not the number of bits to set).
Without this, I would always only get one VCPU for guests created
through libvirt/libxl.
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Although, having it depending on Xen >= 4.3 (by using the proper
libxl feature flag).
Xen currently implements a NUMA placement policy which is basically
the same as the 'interleaved' policy of `numactl', although it can
be applied on a subset of the available nodes. We therefore hardcode
"interleave" as 'numa_mode', and we use the newly introduced libxl
interface to figure out what nodes a domain spans ('numa_nodeset').
With this change, it is now possible to query the NUMA node
affinity of a running domain:
[raistlin@Zhaman ~]$ sudo virsh --connect xen:/// list
Id Name State
----------------------------------------------------
23 F18_x64 running
[raistlin@Zhaman ~]$ sudo virsh --connect xen:/// numatune 23
numa_mode : interleave
numa_nodeset : 1
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
domainGetNumaParameters has a string typed parameter, hence it
is necessary for the libxl driver to support this.
This change implements the connectSupportsFeature hook for the
libxl driver, advertising that VIR_DRV_FEATURE_TYPED_PARAM_STRING
is supported.
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
Cc: Eric Blake <eblake@redhat.com>
Convert the type of loop iterators named 'i', 'j', k',
'ii', 'jj', 'kk', to be 'size_t' instead of 'int' or
'unsigned int', also santizing 'ii', 'jj', 'kk' to use
the normal 'i', 'j', 'k' naming
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Use virDomainObjListRemoveLocked instead of virDomainObjListRemove, as
driver->domains is already taken by virDomainObjListForEach.
Above deadlock can be triggered when libvirtd is started after some
domain have been started by hand (in which case driver will not find
libvirt-xml domain config).
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
By providing the implementation of nodeGetCellsFreeMemory for
the driver. This is all just a matter of properly formatting, in
a way that libvirt like, what Xen provides via libxl_get_numainfo().
[raistlin@Zhaman ~]$ sudo virsh --connect xen:/// freecell --all
0: 25004 KiB
1: 105848 KiB
--------------------
Total: 130852 KiB
Signed-off-by: Dario Faggioli <dario.faggioli@citrix.com>
libxl supports the LIBXL_DISK_BACKEND_QDISK disk backend, where qemu
is used to provide the disk backend. This patch simply maps the
existing <driver name='qemu'/> to LIBXL_DISK_BACKEND_QDISK.
Specifying an unsupported disk format with the tap driver resulted in
a less than helpful error message
error: Failed to start domain test-hvm
error: internal error libxenlight does not support disk driver qed
Change the message to state that the qed format is not supported by
the tap driver, e.g.
error: Failed to start domain test-hvm
error: internal error libxenlight does not support disk format qed
with disk driver tap
While at it, check for unsupported formats in the other driver
backends.
libxl contains logic to determine an appropriate devid for new devices
that do not specify one in their configuration. For all device types
except NICs, the libxl driver allows libxl to determine devid. Do the
same for NICs.
Do not leave uninitialized variables, not all parameters are set in
libxlMake*.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
libxl uses some xenstore entries for hints in memory management
(especially when starting new domain). This includes dom0 memory limit
and Xen free memory margin, based on current system state. Entries are
created at first function usage, so force such call at daemon startup,
which most likely will be before any domain startup.
Also prevent automatic memory management if dom0_mem= option passed to
xen hypervisor - it is known to be incompatible with autoballoon.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
When creating a timer/event handler reference counting is used. So it could
be possible (in theory) that libxlDomainObjPrivateFree is called with
reference counting >1. The problem is that libxlDomainObjPrivateFree leave
the object in an invalid state with ctx freed (but still having dandling
pointer). This can lead timer/event handler to core.
This patch implements a dispose method for libxlDomainObjPrivate, and moves
freeing the libxl ctx to the dispose method, ensuring the ctx is valid while
the object's reference count is > 0.
Signed-off-by: Frediano Ziglio <frediano.ziglio@citrix.com>
Actually only those interface types are handled correctly so reject
others instead of ignoring settings (i.e. treating as bridge/ethernet
anyway).
Also allow <script/> in 'ethernet' (which should be the only
script-allowing type). Keep <script/> allowed in bridge to be compatible
with legacy 'xen' driver.
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
The legacy xen toolstack will set pygrub as the bootloader if not
specified. For compatibility, do the same in the libxl driver
iff not using direct kernel boot.
Currently, the libxl driver reports a connection type of "xenlight".
To be compatible with the legacy Xen driver, it should return "Xen".
Note: I noticed this while testing the libxl driver on OpenStack.
After switching my Xen compute nodes to use the libxl stack, I
could no longer launch instances on those nodes since
hypervisor_type was reported as "xenlight" instead of "xen".
