[RFC PATCH] tests/qemuxml2*/graphics-spice-timeout: skip CPU model check

[Daniel Henrique Barboza]

On 11/17/21 08:02, Boris Fiuczynski wrote:
> On 11/17/21 1:11 AM, Daniel Henrique Barboza wrote:
>> Commit 65b0b746b516 changed spice tests to use latest caps. Before this
>> change, "FLAG_REAL_CAPS" wasn't being set in testQemuInfoInitArgs(). The
>> absence of this flag triggered the code path inside
>> testCompareXMLToArgv() that executed testUpdateQEMUCaps(). This function
>> will update the host CPU via virQEMUCapsUpdateHostCPUModel() into
>> virQEMUCapsInitHostCPUModel().  In this function,
>> virQEMUCapsInitCPUModel() would end up updating the hostCPU inside the
>> qemuCaps (via virQEMUCapsProbeHostCPU()). Before the forementioned
>> commit, the host CPU was being defaulted to x86_64, vendor Intel, for
>> the 'graphics-spice-timeout' test that is using the 'pc' machine type
>> and 'accel=kvm'.
>>
>> Today, "FLAG_REAL_CAPS" is being set because we're using the latest caps
>> from x86_64. This means that the whole code path mentioned above is
>> skipped. qemuCaps are now being loaded via virQEMUCapsLoadCache()
>> directly.  Without the handling being done by testUpdateQEMUCaps(), the
>> host CPU is being retrieved later on, down below
>> qemuProcessCreatePretendCmdPrepare() into qemuProcessUpdateGuestCPU().
>> The latter will attempt to update the domain cpu and executing a
>> virCPUCompare with the hostCPU and def->cpu.
>>
>> All this logic ended up causing a failure of the
>> 'graphics-spice-timeout' test in ppc64 and s390x hosts. This test is
>> being run with KVM acceleration, and the KVM driver for ppc64 and s390x
>> will return a default x86_64 CPU with vendor "AMD", making
>> virCPUCompare() fail with the following message:
>>
>> "QEMU XML-2-ARGV graphics-spice-timeout.x86_64-latest   ... libvirt: CPU
>> Driver error : the CPU is incompatible with host CPU: host CPU vendor does
>> not match required CPU vendor Intel"
>>
>> Fix this test by setting cpu check='none' and avoid the virCPUCompare()
>> that causes the problem for ppc64 and s390x hosts.
>>
>> Reported-by: Boris Fiuczynski <fiuczy at linux.ibm.com>
>> Signed-off-by: Daniel Henrique Barboza <danielhb413 at gmail.com>
>> ---
>>
>> Sending as a RFC because I'm not sure if this patch fixes the
>> problem for s390x. Boris, can you please test and see if this
>> fix works for you?
> 
> The proposed patch works on s390x as well.
> 
> Reviewed-by: Boris Fiuczynski <fiuczy at linux.ibm.com>


Thanks for checking. I'll hold this patch a little* to see if we can fix the
real cause of the bug, which can be something to do with how we are defaulting
x86_64 cpus for ppc64 and s390x.



* just a couple of days. No need to let the build being broken more than that.



Daniel


> 
>>
>>
>>   tests/qemuxml2argvdata/graphics-spice-timeout.xml               | 2 +-
>>   .../qemuxml2xmloutdata/graphics-spice-timeout.x86_64-latest.xml | 2 +-
>>   2 files changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/tests/qemuxml2argvdata/graphics-spice-timeout.xml b/tests/qemuxml2argvdata/graphics-spice-timeout.xml
>> index 065318651f..33dae5c4bf 100644
>> --- a/tests/qemuxml2argvdata/graphics-spice-timeout.xml
>> +++ b/tests/qemuxml2argvdata/graphics-spice-timeout.xml
>> @@ -15,7 +15,7 @@
>>       <apic/>
>>       <pae/>
>>     </features>
>> -  <cpu match='exact'>
>> +  <cpu match='exact' check='none'>
>>       <model>core2duo</model>
>>       <vendor>Intel</vendor>
>>       <topology sockets='1' dies='1' cores='2' threads='1'/>
>> diff --git a/tests/qemuxml2xmloutdata/graphics-spice-timeout.x86_64-latest.xml b/tests/qemuxml2xmloutdata/graphics-spice-timeout.x86_64-latest.xml
>> index fd34a6caf5..9e6782d00b 100644
>> --- a/tests/qemuxml2xmloutdata/graphics-spice-timeout.x86_64-latest.xml
>> +++ b/tests/qemuxml2xmloutdata/graphics-spice-timeout.x86_64-latest.xml
>> @@ -15,7 +15,7 @@
>>       <apic/>
>>       <pae/>
>>     </features>
>> -  <cpu mode='custom' match='exact' check='partial'>
>> +  <cpu mode='custom' match='exact' check='none'>
>>       <model fallback='allow'>core2duo</model>
>>       <vendor>Intel</vendor>
>>       <topology sockets='1' dies='1' cores='2' threads='1'/>
>>
> 
>