This patch adds an inline python code for reading MSR features. Since
reading MSRs is a privileged operation, we have to read them from
/dev/cpu/*/msr if it is readable (i.e., the script runs as root) or
fallback to using KVM ioctl which can be done by any user that can start
virtual machines.
The python code is inlined rather than provided in a separate script
because whenever there's an issue with proper detection of CPU features,
we ask the reporter to run cpu-gather.sh script to give us all data we
need to know about the host CPU. Asking them to run several scripts
would likely result in one of them being ignored or forgotten.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The parseMapFeature for parsing features from CPU map XML can be easily
generalized to support more feature types.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Let's make sure the current CPUID specific code is only applied to CPUID
features.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This will let us simplify the code since the dictionary keys will match
attribute names in various XMLs.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
leaf["eax"] & eax > 0 check works correctly only if there's at most 1
bit set in eax. Luckily that's been always the case, but fixing this
could save us from future surprises.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The function will have to deal with both CPUID and MSR features.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
We don't really need to parse CPU data from QEMU older than 2.9 (i.e.,
before query-cpu-model-expansion) at this point. But even if there's a
need to do so, we can always use an older version of this script to do
the conversion.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
Introduced in QEMU 3.1.0 by commit
c7a88b52f62b30c04158eeb07f73e3f72221b6a8
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This fixes several CPUs which were incorrectly detected as
Skylake-Client.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
This fixes several CPUs which were incorrectly detected as a different
CPU model.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The signature computation code is not too complicated and it will likely
never change so testing it is not very important. We do it mostly for a
nice side effect of easily accessible signature numbers for all CPU
data files.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The tests/cputestdata/cpu-parse.sh would produce JSON files with QEMU
replies which wouldn't pass syntax-check. Let's fix this by not emitting
an extra new line after reformatting the JSON file.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The tests/cputestdata/cpu-parse.sh script has been broken since the
cpu_map.xml file was split into several XMLs.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
The feature was added to QEMU in 3.1.0 and it is currently blocking
migration, which is expected to change in the future. Luckily 3.1.0 is
new enough to give us migratability hints on each feature via
query-cpu-model-expension, which means we don't need to use the
"migratable" attribute on the CPU map XML.
The kernel calls this feature arch_capabilities and RHEL/CentOS 7.* use
arch-facilities. Apparently some CPU test files were gathered with the
RHEL version of QEMU. Let's update the test files to avoid possible
confusion about the correct naming.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
QEMU commits:
e37a5c7fa4 (v2.12.0)
i386: Add Intel Processor Trace feature support
c2f193b538 (v2.7.0)
target-i386: Add support for UMIP and RDPID CPUID bits
aff9e6e46a (v2.12.0)
x86/cpu: Enable new SSE/AVX/AVX512 cpu features
f77543772d (v2.9.0)
x86: add AVX512_VPOPCNTDQ features
5131dc433d (v3.1.0)
i386: Add CPUID bit for PCONFIG
59a80a19ca (v3.1.0)
i386: Add CPUID bit for WBNOINVD
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Replace the print statement, that is only available in Py2, with a
print function that is available in both Py2 and Py3 and drop the
explicit python version in the shebang.
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Radostin Stoyanov <rstoyanov1@gmail.com>
PEP8 recommends not having spaces around = in a keyword argument or
a default parameter value.
https://www.python.org/dev/peps/pep-0008/#other-recommendations
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Radostin Stoyanov <rstoyanov1@gmail.com>
This is a variant of EPYC with indirect branch prediction protection.
The only difference between EPYC and EPYC-IBPB is the added "ibpb"
feature.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
This is a variant of Skylake-Server with indirect branch prediction
protection. The only difference between Skylake-Server and
Skylake-Server-IBRS is the added "spec-ctrl" feature.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
This is a variant of Skylake-Client with indirect branch prediction
protection. The only difference between Skylake-Client and
Skylake-Client-IBRS is the added "spec-ctrl" feature.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
This is a variant of Broadwell with indirect branch prediction
protection. The only difference between Broadwell and Broadwell-IBRS is
the added "spec-ctrl" feature.
The Broadwell-IBRS model in QEMU is a bit different since Broadwell got
several additional features since we added it in cpu_map.xml:
abm, arat, f16c, rdrand, vme, xsaveopt
Adding them only to the -IBRS variant would confuse our CPU detection
code.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
This is a variant of Haswell-noTSX with indirect branch prediction
protection. The only difference between Haswell-noTSX and
Haswell-noTSX-IBRS is the added "spec-ctrl" feature.
The Haswell-noTSX-IBRS model in QEMU is a bit different since
Haswell-noTSX got several additional features since we added it in
cpu_map.xml:
arat, abm, f16c, rdrand, vme, xsaveopt
Adding them only to the -IBRS variant would confuse our CPU detection
code.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The CPU contains the updated microcode for CVE-2017-5715.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The CPU contains the updated microcode for CVE-2017-5715.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The CPU contains the updated microcode for CVE-2017-5715.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The CPU contains the updated microcode for CVE-2017-5715.
The *-guest.xml and *-json.xml CPU definitions use Skylake-Client CPU
model rather than Broadwell. This is similar to Xeon-E5-2650-v4 and it
is caused by our CPU model selection code when no model matches the CPU
signature (family + model). We'd need to maintain a complete list of CPU
signatures for our CPU models to fix this.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The CPU contains the updated microcode for CVE-2017-5715.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The cpuidMap in cpu-cpuid.py was created for converting old data files
(with QEMU's feature-words bits) to the new model-expansion based data.
When I added tests for CPU live update based on disabled/enabled feature
lists I shamelessly used the existing cpuidMap for generating the
*-{enabled,disabled}.xml data files. Thus any new CPUID bits which are
not present in the original cpuidMap would be ignored. The correct thing
to do is to use cpu_map.xml.
All data files were fixed by running the following command:
./cpu-cpuid.py diff *.json
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Without the fix in the previous patch the JSON data from QEMU would be
interpreted as Haswell-noTSX because x86DataFilterTSX would filter rtm
and hle features as a result of
family == 6 && model == 63 && stepping < 4
test even though this CPU has stepping == 4.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
xsaveopt is artificially removed from the host to test disabled feature
which is only included in QEMU's version of the CPU model.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
arat is now enabled even if the hardware does not support it.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
This CPU was incorrectly detected as SandyBridge before because the
number of additional <feature> elements was the same for both
SandyBridge and Westmere CPU models, but SandyBridge is newer (the CPU
signature does not help here because it doesn't match any signature
defined in cpu_map.xml). But since QEMU's version of SandyBridge CPU
model contains xsaveopt which needs to be disabled, Westmere becomes the
best CPU model when translating CPUID data to virCPUDef. Unfortunately,
this doesn't help with translating the data we got from QEMU and the CPU
model is still computed as SandyBridge in this case.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
The unavailable features do not make any difference in this case,
because this is a SandyBridge CPU which has an empty list of unavailable
features.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Gather query-cpu-definitions results and use them for testing CPU model
usability blockers in CPUID to virCPUDef translation.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
Various version of json_reformat use different number of spaces for
indenting. Let's use a simple python reformatter to gain full control
over the formatting for consistent results.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: John Ferlan <jferlan@redhat.com>
In the past we updated host-model CPUs with host CPU data by adding a
model and features, but keeping the host-model mode. And since the CPU
model is not normally formatted for host-model CPU defs, we had to pass
the updateCPU flag to the formatting code to be able to properly output
updated host-model CPUs. Libvirt doesn't do this anymore, host-model
CPUs are turned into custom mode CPUs once updated with host CPU data
and thus there's no reason for keeping the hacks inside CPU XML
formatters.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
This is particularly useful on operating systems that don't ship
Python as part of the base system (eg. FreeBSD) while still working
just as well as it did before on Linux.
While at it, make it explicit that our scripts are only going to
work with Python 2, and remove the usage of unbuffered I/O, which
as far as I can tell has no effect on the output files.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Available since QEMU 2.10.0 (specifically commit
v2.9.0-2233-g53f9a6f45f).
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
The features were added to QEMU by commit v2.4.0-1690-gf7fda28094 as
Skylake Server features.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
Add a new CPU model called 'EPYC' to model processors from AMD EPYC
family (which includes EPYC 76xx,75xx,74xx, 73xx and 72xx).
The following features bits have been added/removed compare to Opteron_G5
Added: monitor, movbe, rdrand, mmxext, ffxsr, rdtscp, cr8legacy, osvw,
fsgsbase, bmi1, avx2, smep, bmi2, rdseed, adx, smap, clfshopt, sha
xsaveopt, xsavec, xgetbv1, arat
Removed: xop, fma4, tbm
The patch is depend on EPYC CPU model supported introduced in qemu [1]
[1] https://patchwork.kernel.org/patch/9902205/
Cc: Tom Lendacky <Thomas.Lendacky@amd.com>
Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Reviewed-by: Pavel Hrdina <phrdina@redhat.com>
CPU features unknown to a hypervisor will not be present in dataDisabled
even though the features won't naturally be enabled because.
Thus any features we asked for which are not in dataEnabled should be
considered disabled.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
All CPU features which QEMU does not know about but libvirt knows them
(currently "cmt" is the only one) are implicitly disabled by QEMU and
should be present in x86_64-cpuid-*-disabled.xml.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Commit v3.1.0-26-gd60012b4e started filtering hle and rtm features from
broken Intel Haswell CPUs. QEMU implemented similar functionality and
thus it doesn't report rtm and hle features as enabled for Core i5-4670T
CPU anymore.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The new command can be used to generate test data for virCPUUpdateLive.
When "cpu-cpuid.py diff x86-cpuid-Something.json" is run, it reads raw
CPUID data stored in x86-cpuid-Something.xml and CPUID data from QEMU
stored in x86-cpuid-Something.json to produce two more CPUID files:
x86-cpuid-Something-enabled.xml and x86-cpuid-Something-disabled.xml.
- x86-cpuid-Something-enabled.xml will contain CPUID bits present in
x86-cpuid-Something.json (i.e., enabled by QEMU for the "host" CPU)
- x86-cpuid-Something-disabled.xml will contain all CPUID bits from
x86-cpuid-Something.xml which are not present in
x86-cpuid-Something.json (i.e., CPUID bits which the host CPU
supports, but QEMU does not enable them for the "host" CPU)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The new script is going to be more general and the original
functionality can be requested by "cpu-cpuid.py convert".
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>
All existing Haswell CPUID data were gathered from CPUs with broken TSX.
Let's add new data for Haswell with correct TSX implementation.
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 original test didn't use family/model numbers to make better
decisions about the CPU model and thus mis-detected the model in the two
cases which are modified in this commit. The detected CPU models now
match those obtained from raw CPUID data.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Converted by running the following command, renaming the files as
*.new, and committing only the *.new files.
(cd tests/cputestdata; ./cpu-convert.py *.json)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Instantiating "host" CPU and querying it using qom-get has been the only
way of probing host CPU via QEMU until 2.9.0 implemented
query-cpu-model-expansion for x86_64. Even though libvirt never really
used the old way its result can be easily converted into the one
produced by query-cpu-model-expansion. Thus we can reuse the original
test data and possible get new data from hosts where QEMU does not
support the new QMP command.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
While "x86" is a CPU sub driver name, it is not a recognized name of any
architecture known to libvirt. Let's use "x86_64" prefix which can be
used with virArch APIs.
Signed-off-by: Jiri Denemark <jdenemar@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>
The API is no longer used anywhere else since it was replaced by a much
saner work flow utilizing new APIs that work on virCPUDefPtr directly:
virCPUCompare, virCPUUpdate, and virCPUTranslate.
Not testing the new work flow caused some bugs to be hidden. This patch
reveals them, but doesn't attempt to fix them. To make sure all test
still pass after this patch, all affected test results are modified to
pretend the tests succeeded. All of the bugs will be fixed in the
following commits and the artificial modifications will be reverted.
The following is the list of bugs in the new CPU model work flow:
- a guest CPU with mode='custom' and missing <vendor/> gets the vendor
copied from host's CPU (the vendor should only be copied to host-model
CPUs):
DO_TEST_UPDATE("x86", "host", "min", VIR_CPU_COMPARE_IDENTICAL)
DO_TEST_UPDATE("x86", "host", "pentium3", VIR_CPU_COMPARE_IDENTICAL)
DO_TEST_GUESTCPU("x86", "host-better", "pentium3", NULL, 0)
- when a guest CPU with mode='custom' needs to be translated into
another model because the original model is not supported by a
hypervisor, the result will have its vendor set to the vendor of the
original CPU model as specified in cpu_map.xml even if the original
guest CPU XML didn't contain <vendor/>:
DO_TEST_GUESTCPU("x86", "host", "guest", model486, 0)
DO_TEST_GUESTCPU("x86", "host", "guest", models, 0)
DO_TEST_GUESTCPU("x86", "host-Haswell-noTSX", "Haswell-noTSX",
haswell, 0)
- legacy POWERx_v* model names are not recognized:
DO_TEST_GUESTCPU("ppc64", "host", "guest-legacy", ppc_models, 0)
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
In some cases preferred model doesn't really do anything since the
result remains the same even if it is removed.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Using a preferred CPU model which is not in the list of CPU models
supported by a hypervisor does not make sense.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Guest CPUs with match='minimum' should always be updated to match host
CPU model. Trying to get different results by supplying preferred models
does not make sense.
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>
Some Intel processor families (e.g. the Intel Xeon processor E5 v3
family) introduced some PQos (Platform Qos) features, including CMT
(Cache Monitoring technology) and MBM (Memory Bandwidth Monitoring),
to monitor or control shared resource. This patch add them into x86
part of cpu_map.xml to be used for applications based on libvirt to
get cpu capabilities. For example, Nova in OpenStack schedules guests
based on the CPU features that the host has.
Signed-off-by: Qiaowei Ren <qiaowei.ren@intel.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>
The CPU model was implemented in QEMU by commit f6f949e929.
The change to i7-5600U is wrong since it's a 5th generation CPU, i.e.,
Broadwell rather than Skylake, but that's just the result of our CPU
detection code (which is fixed by the following commit).
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The actual CPU model in the data files is Penryn which makes the file
name look rather strange. Well, one of them contains Nehalem, but that's
a bug which will be fixed soon.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
As a side effect this changes the order of CPU features in XMLs
generated by libvirt, but that's not a big deal since the order there is
insignificant.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
So far we only test CPUID -> CPU def conversion on artificial CPUID data
computed from another CPU def. This patch adds the infrastructure to
test this conversion on real data gathered from a host CPU and two
helper scripts for adding new test data:
- cpu-gather.sh runs cpuid tool and qemu-system-x86_64 to get CPUID data
from the host CPU; this is what users can be asked to run if they run
into an issue with host CPU detection in libvirt
- cpu-parse.sh takes the data generated by cpu-gather.sh and creates
data files for CPU detection tests
The CPUID data queried from QEMU will eventually switch to the format
used by query-host-cpu QMP command once QEMU implements it. Until then
we just spawn QEMU with -cpu host and query the guest CPU in QOM. They
should both provide the same CPUID results, but query-host-cpu does not
require any guest CPU to be created by QEMU.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
When computing CPU data for a given guest CPU we should set CPUID vendor
bits appropriately so that we don't lose the vendor when transforming
CPU data back to XML description.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
There's no reason for keeping the features in a linked list. Especially
when we know upfront the total number of features we are loading.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Limitations of the POWER architecture mean that you can't run
eg. a POWER7 guest on a POWER8 host when using KVM. This applies
to all guests, not just those using VIR_CPU_MATCH_STRICT in the
CPU definition; in fact, exact and strict CPU matching are
basically the same on ppc64.
This means, of course, that hosts using different CPUs have to be
considered incompatible as well.
Change ppc64Compute(), called by cpuGuestData(), to reflect this
fact and update test cases accordingly.
Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1250977
QEMU 2.3 adds these new models to cover Haswell and Broadwell CPUs with
updated microcode. Luckily, they also reverted former the machine type
specific changes to existing models. And since these changes were never
released, we don't need to hack around them in libvirt.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Commit fba6bc4 introduced support for the 'invtsc' feature,
which blocks migration. We should not include it in the
host-model CPU by default, because it's intended to be used
with migration.
https://bugzilla.redhat.com/show_bug.cgi?id=1138221
https://bugzilla.redhat.com/show_bug.cgi?id=1049391
When all source CPU XMLs contain just a single CPU model (with a
possibly varying set of additional feature elements),
virConnectBaselineCPU will try to use this CPU model in the computed
guest CPU. Thus, when used on just a single CPU (useful with
VIR_CONNECT_BASELINE_CPU_EXPAND_FEATURES), the result will not use a
different CPU model.
If the computed CPU uses the source model, set fallback mode to 'forbid'
to make sure the guest CPU will always be as close as possible to the
source CPUs.
Currently the virConnectBaselineCPU API does not expose the CPU features
that are part of the CPU's model. This patch adds a new flag,
VIR_CONNECT_BASELINE_CPU_EXPAND_FEATURES, that causes the API to explicitly
list all features that are part of that model.
Signed-off-by: Don Dugger <donald.d.dugger@intel.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Until now CPU features inherited from a specified CPU model could only
be overridden with 'disable' policy. With this patch, any explicitly
specified feature always overrides the same feature inherited from a CPU
model regardless on the specified policy.
The CPU in x86-exact-force-Haswell.xml would previously be incompatible
with x86-host-SandyBridge.xml CPU even though x86-host-SandyBridge.xml
provides all features required by x86-exact-force-Haswell.xml.
We found few more AMD-specific features in cpu64-rhel* models that
made it impossible to start qemu guest on Intel host (with this
setting) even though qemu itself starts correctly with them.
This impacts one test, thus the fix in tests/cputestdata/.
Recently (or not so recently) QEMU added the kvm32 and kvm64
architectures, representing a least common denominator of all
hosts that can run KVM. Add them to the machine map.
Also, some features that TCG supports were added to qemu64.
Add them to the cpu_map.xml whenever KVM is guaranteed to support
those. We still have to leave some out, because they would not
be available to guests running on older hosts.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VIR_DOMAIN_XML_UPDATE_CPU flag for virDomainGetXMLDesc may be used to
get updated custom mode guest CPU definition in case it depends on host
CPU. This patch implements the same behavior for host-model and
host-passthrough CPU modes.
The mode can be either of "custom" (default), "host-model",
"host-passthrough". The semantics of each mode is described in the
following examples:
- guest CPU is a default model with specified topology:
<cpu>
<topology sockets='1' cores='2' threads='1'/>
</cpu>
- guest CPU matches selected model:
<cpu mode='custom' match='exact'>
<model>core2duo</model>
</cpu>
- guest CPU should be a copy of host CPU as advertised by capabilities
XML (this is a short cut for manually copying host CPU specification
from capabilities to domain XML):
<cpu mode='host-model'/>
In case a hypervisor does not support the exact host model, libvirt
automatically falls back to a closest supported CPU model and
removes/adds features to match host. This behavior can be disabled by
<cpu mode='host-model'>
<model fallback='forbid'/>
</cpu>
- the same as previous returned by virDomainGetXMLDesc with
VIR_DOMAIN_XML_UPDATE_CPU flag:
<cpu mode='host-model' match='exact'>
<model fallback='allow'>Penryn</model> --+
<vendor>Intel</vendor> |
<topology sockets='2' cores='4' threads='1'/> + copied from
<feature policy='require' name='dca'/> | capabilities XML
<feature policy='require' name='xtpr'/> |
... --+
</cpu>
- guest CPU should be exactly the same as host CPU even in the aspects
libvirt doesn't model (such domain cannot be migrated unless both
hosts contain exactly the same CPUs):
<cpu mode='host-passthrough'/>
- the same as previous returned by virDomainGetXMLDesc with
VIR_DOMAIN_XML_UPDATE_CPU flag:
<cpu mode='host-passthrough' match='minimal'>
<model>Penryn</model> --+ copied from caps
<vendor>Intel</vendor> | XML but doesn't
<topology sockets='2' cores='4' threads='1'/> | describe all
<feature policy='require' name='dca'/> | aspects of the
<feature policy='require' name='xtpr'/> | actual guest CPU
... --+
</cpu>
In case a hypervisor doesn't support the exact CPU model requested by a
domain XML, we automatically fallback to a closest CPU model the
hypervisor supports (and make sure we add/remove any additional features
if needed). This patch adds 'fallback' attribute to model element, which
can be used to disable this automatic fallback.
