Because of the changes done in the previous commit, @host is already a
migratable CPU and there's no need to do any additional filtering.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
This new internal API makes a copy of virCPUDef while removing all
features which would block migration. It uses cpu_map.xml as a database
of such features, which should only be used as a fallback when we cannot
get the data from a hypervisor. The main goal of this API is to decouple
this filtering from virCPUUpdate so that the hypervisor driver can
filter the features according to the hypervisor.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The public API flags are handled by the cpuBaselineXML wrapper. The
internal cpuBaseline API only needs to know whether it is supposed to
drop non-migratable features.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
cpuBaseline is responsible for computing a baseline CPU while feature
expansion is done by virCPUExpandFeatures. The cpuBaselineXML wrapper
(used by hypervisor drivers to implement virConnectBaselineCPU API)
calls cpuBaseline followed by virCPUExpandFeatures if requested by
VIR_CONNECT_BASELINE_CPU_EXPAND_FEATURES flag.
The features in the three changed test files had to be sorted using
"sort -k 3" because virCPUExpandFeatures returns a sorted list of
features.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Having to use cpuBaseline with VIR_CONNECT_BASELINE_CPU_EXPAND_FEATURES
flag to expand CPU features is strange. Not to mention that cpuBaseline
can only expand host CPU definitions (i.e., it completely ignores
feature policies). The new virCPUExpandFeatures API is designed to work
with both host and guest CPU definitions.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
When starting a domain with custom guest CPU specification QEMU may add
or remove some CPU features. There are several reasons for this, e.g.,
QEMU/KVM does not support some requested features or the definition of
the requested CPU model in libvirt's cpu_map.xml differs from the one
QEMU is using. We can't really avoid this because CPU models are allowed
to change with machine types and libvirt doesn't know (and probably
doesn't even want to know) about such changes.
Thus when we want to make sure guest ABI doesn't change when a domain
gets migrated to another host, we need to update our live CPU definition
according to the CPU QEMU created. Once updated, we will change CPU
checking to VIR_CPU_CHECK_FULL to make sure the virtual CPU created
after migration exactly matches the one on the source.
https://bugzilla.redhat.com/show_bug.cgi?id=822148https://bugzilla.redhat.com/show_bug.cgi?id=824989
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
When creating host CPU definition usable with a given emulator, the CPU
should not be defined using an unsupported CPU model. The new @models
and @nmodels parameters can be used to limit CPU models which can be
used in the result.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
cpuNodeData has always been followed by cpuDecode as no hypervisor
driver is really interested in raw CPUID data for a host CPU. Let's
create a new CPU driver API which returns virCPUDefPtr directly.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
All Intel Haswell processors (except Xeon E7 v3 with stepping >= 4) have
TSX disabled by microcode update. As not all CPUs are guaranteed to be
patched with microcode updates we need to explicitly disable TSX on
affected CPUs to avoid its accidental usage.
https://bugzilla.redhat.com/show_bug.cgi?id=1406791
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The API is useful for creating virCPUData in a hypervisor driver from
data we got by querying the hypervisor.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The API is useful for creating virCPUData in a hypervisor driver from
data we got by querying the hypervisor.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The API is useful for creating virCPUData in a hypervisor driver from
data we got by querying the hypervisor.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The CPU driver provides APIs to create and free virCPUDataPtr. Thus all
APIs exported from the driver should work with that rather than
requiring the caller to pass a pointer to an internal part of the
structure.
In other words
virCPUx86DataAddCPUID(cpudata, &cpuid)
is much better than the original
virCPUx86DataAddCPUID(&cpudata->data.x86, &cpuid)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The new API is called virCPUDataFree. Individual CPU drivers are no
longer required to implement their own freeing function unless they need
to free architecture specific data from virCPUData.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Strings associated with virDomainHyperv values in domain_conf.c are used to
construct HyperV CPU features names to be compared with names defined in
cpu_x86_data.h and the names for HyperV "spinlocks" feature don't match.
This leads to a misleading warning:
"host doesn't support hyperv 'spinlocks' feature" even when it's supported.
Let's fix it and rename along with it VIR_CPU_x86_KVM_HV_SPINLOCK to
VIR_CPU_x86_KVM_HV_SPINLOCKS.
Signed-off-by: Maxim Nestratov <mnestratov@virtuozzo.com>
virCPUDefStealModel is called with keepVendor == true which means the
cpu structure will keep its original vendor/vendor_id values. Thus it
makes no sense to copy them to the translated definition as they won't
be used there anyway. Except that the translated->vendor pointer might
get lost in x86Decode.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
We have couple of functions that operate over NULL terminated
lits of strings. However, our naming sucks:
virStringJoin
virStringFreeList
virStringFreeListCount
virStringArrayHasString
virStringGetFirstWithPrefix
We can do better:
virStringListJoin
virStringListFree
virStringListFreeCount
virStringListHasString
virStringListGetFirstWithPrefix
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Guest CPU definitions with mode='custom' and missing <vendor> are
expected to run on a host CPU from any vendor as long as the required
CPU model can be used as a guest CPU on the host. But even though no CPU
vendor was explicitly requested we would sometimes force it due to a bug
in virCPUUpdate and virCPUTranslate.
The bug would effectively forbid cross vendor migrations even if they
were previously working just fine.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Both cpuCompare* APIs are renamed to virCPUCompare*. And they should now
work for any guest CPU definition, i.e., even for host-passthrough
(trivial) and host-model CPUs. The implementation in x86 driver is
enhanced to provide a hint about -noTSX Broadwell and Haswell models
when appropriate.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The function is similar to virCPUDataCheckFeature, but it works directly
on CPU definition rather than requiring it to be transformed into CPU
data first.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The API is supposed to make sure the provided CPU definition does not
use a CPU model which is not supported by the hypervisor (if at all
possible, of course).
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Keeping nfeatures_max set to 0 while nfeatures > 0 and some features are
already stored in features array is just asking for problems once we
want to add a new feature into the array.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The reworked API is now called virCPUUpdate and it should change the
provided CPU definition into a one which can be consumed by the QEMU
command line builder:
- host-passthrough remains unchanged
- host-model is turned into custom CPU with a model and features
copied from host
- custom CPU with minimum match is converted similarly to host-model
- optional features are updated according to host's CPU
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
x86ModelFromCPU is used to provide CPUID data for features matching
@policy. This patch allows callers to set @policy to -1 to get combined
CPUID for all CPU features (including those implicitly provided a CPU
model) specified in CPU def.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
When starting a guest and copying host vendor cpuid to the guest
cpu, libvirtd would crash if the host cpu contained a NULL vendor
field. Avoid the crash by checking for a valid vendor in the host
cpu before copying the cpuid to the guest cpu.
For completeness, here is a backtrace from the crash
(gdb) bt
f0 0x00007ffff739bf33 in x86DataCpuid (cpuid=0x8, cpuid=0x8,
data=data@entry=0x7fffb800ee78) at cpu/cpu_x86.c:287
f1 virCPUx86DataAddCPUID (data=data@entry=0x7fffb800ee78, cpuid=0x8)
at cpu/cpu_x86.c:355
f2 0x00007ffff739ef47 in x86Compute (host=<optimized out>, cpu=0x7fffb8000cc0,
guest=0x7fffecca7348, message=<optimized out>) at cpu/cpu_x86.c:1580
f3 0x00007fffd2b38e53 in qemuBuildCpuModelArgStr (migrating=false,
hasHwVirt=<synthetic pointer>, qemuCaps=0x7fffb8001040, buf=0x7fffecca7360,
def=0x7fffc400ce20, driver=0x1c) at qemu/qemu_command.c:6283
f4 qemuBuildCpuCommandLine (cmd=cmd@entry=0x7fffb8002f60,
driver=driver@entry=0x7fffc80882c0, def=def@entry=0x7fffc400ce20,
qemuCaps=qemuCaps@entry=0x7fffb8001040, migrating=<optimized out>)
at qemu/qemu_command.c:6445
(gdb) f2
(gdb) p *host_model
$23 = {name = 0x7fffb800ec50 "qemu64", vendor = 0x0, signature = 0, data = {
len = 2, data = 0x7fffb800e720}}
Since the introduction of CMT features (commit v1.3.5-461-gf294b83)
starting a domain with host-model CPU on a host which supports CMT fails
because QEMU complains about unknown 'cmt' feature:
qemu-system-x86_64: CPU feature cmt not found
https://bugzilla.redhat.com/show_bug.cgi?id=1355857
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
By removing a non-migratable feature in a for loop we would fail to drop
every second non-migratable feature if the features array contained
several of them in a row.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Our current detection code uses just the number of CPU features which
need to be added/removed from the CPU model to fully describe the CPUID
data. The smallest number wins. But this may sometimes generate wrong
results as one can see from the fixed test cases. This patch modifies
the algorithm to prefer the CPU model with matching signature even if
this model results in a longer list of additional features.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
CPUID instruction normally takes its parameter from EAX, but sometimes
ECX is used as an additional parameter. This patch prepares the x86 CPU
driver code for the new 'ecx_in' CPUID parameter.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The internal features are only used in explicit checks with
cpuHasFeature. Loading them into the CPU map is dangerous since the
features may accidentally be reported to users when decoding CPUID data.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
virCPUData, virCPUx86Feature, and virCPUx86Model all contained a pointer
to virCPUx86Data, which was not very nice since the real CPUID data were
accessible by yet another pointer from virCPUx86Data. Moreover, using
virCPUx86Data directly will make static definitions of internal CPU
features a bit easier.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
CPUID instruction normally takes its parameter from EAX, but sometimes
ECX is used as an additional parameter. Let's rename 'function' to
'eax_in' in preparation for adding 'ecx_in'.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
