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>
Pretending (partial) support for something we don't understand is risky.
Reporting a failure is much better.
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>
Both ARM and AArch64 drivers are exactly the same (modulo function
names). Let's use just one driver for all ARM architectures.
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>
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>
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>
For two reasons:
- 0x00000001 is very similar to 0x80000001, but 0x01 is visually
different
- 0x01 format is consistent with CPUID manual
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 and struct ppc64_model structures contained a pointer to
virCPUppc64Data, which was not very nice since the real data were
accessible by yet another level of pointers from virCPUppc64Data.
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>
A CPU data XML file already contains the architecture, let the parser
use it to detect which CPU driver should be used to parse the rest of
the file.
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>
cpu/cpu_ppc64.c: In function 'ppc64Compute':
cpu/cpu_ppc64.c:620:27: error: potential null pointer dereference [-Werror=null-dereference]
if (STRNEQ(guest_model->name, host_model->name)) {
~~~~~~~~~~~^~~
cpu/cpu_ppc64.c:620:9: note: in expansion of macro 'STRNEQ'
if (STRNEQ(guest_model->name, host_model->name)) {
^~~~~~
cc1: all warnings being treated as errors
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
All callers of cpuGetModels expect @models to be NULL-terminated. Once
both x86GetModels and ppc64GetModels were fixed to meet this
expectation, we can explicitly document it.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
The architecture specific loaders are now called with a list of all
elements of a given type (rather than a single element at a time). This
avoids the need to reallocate the arrays in CPU maps for each element.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
There's no reason for keeping the models in a linked list. Especially
when we know upfront the total number of models we are loading.
As a nice side effect, this fixes ppc64GetModels to always return a
NULL-terminated list of models.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
There's no reason for keeping the vendors in a linked list. Especially
when we know upfront the total number of models we are loading.
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>
There's no reason for keeping the vendors in a linked list. Especially
when we know upfront the total number of models we are loading.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
There's no reason for keeping the models in a linked list. Especially
when we know upfront the total number of models we are loading.
As a nice side effect, this fixes x86GetModels to always return a
NULL-terminated list of models.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
When searching for the best CPU model for CPUID data we can easily
ignore models with non-matching vendor before spending time on CPUID
data to virCPUDef conversion.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
Splitting the comparison into a separate function makes the code cleaner
and easier to update in the future.
Signed-off-by: Jiri Denemark <jdenemar@redhat.com>
