Re: [RFC 0/3] qtest: pick tests that require KVM at runtime

[Philippe Mathieu-Daudé]

On 6/22/21 9:20 AM, Thomas Huth wrote:
> On 16/06/2021 17.24, Igor Mammedov wrote:
>>
>> Sometimes it's necessary to execute a test that depends on KVM,
>> however qtest is not aware if tested QEMU binary supports KVM
>> on the host it the test is executed.
>>
>> For an example:
>>   test q35 machine with intel_iommu
>>   This test will run only is KVM is available and fail
>>   to start QEMU if it fallsback to TCG, thus failing whole test.
>>   So if test is executed in VM where nested KVM is not enabled
>>   or on other than x86 host, it will break 'make check-qtest'
>>
>> Series adds a lightweight qtest_has_kvm() check, which abuses
>> build system and should help to avoid running KVM only tests
>> on hosts that do not support it.
> 
> You also might want to update the check in tests/qtest/migration-test.c
> while you're at it.
> 
>> PS:
>> there is an alternative 'query-accels' QMP command proposal
>> https://patchwork.kernel.org/project/qemu-devel/patch/20210503211020.894589-3-philmd@redhat.com/
>>
>> which I think is more robust compared to qtest_has_kvm() and
>> could be extended to take into account machine type.
> 
> Could you please get in touch with Philippe directly and discuss which
> way to go? We certainly don't need two approaches in the end...

I'm certainly fine if Igor wants to restart this effort :)

Maybe doing as Claudio suggested, start have qtest_has_accel()
tests accel with Igor's shortpath first, then fallback to
'query-accels' QMP command?