Re: [PATCH-for-9.0 v2 01/19] tests/avocado: Add 'guest:xen' tag to tests running Xen guest

[David Woodhouse <dwmw2@xxxxxxxxxxxxx>]

On 14 November 2023 10:13:14 GMT-05:00, "Philippe Mathieu-Daudé" 
<philmd@xxxxxxxxxx> wrote:
>On 14/11/23 16:08, David Woodhouse wrote:
>> On 14 November 2023 10:00:09 GMT-05:00, "Philippe Mathieu-Daudé" 
>> <philmd@xxxxxxxxxx> wrote:
>>> On 14/11/23 15:50, David Woodhouse wrote:
>>>> On 14 November 2023 09:37:57 GMT-05:00, "Philippe Mathieu-Daudé" 
>>>> <philmd@xxxxxxxxxx> wrote:
>>>>> Add a tag to run all Xen-specific tests using:
>>>>> 
>>>>>    $ make check-avocado AVOCADO_TAGS='guest:xen'
>>>>> 
>>>>> Signed-off-by: Philippe Mathieu-Daudé <philmd@xxxxxxxxxx>
>>>>> ---
>>>>> tests/avocado/boot_xen.py      | 3 +++
>>>>> tests/avocado/kvm_xen_guest.py | 1 +
>>>>> 2 files changed, 4 insertions(+)
>>>> 
>>>> Those two are very different. One runs on Xen, the other on KVM. Do we 
>>>> want to use the same tag for both?
>>> 
>>> My understanding is,
>>> - boot_xen.py runs Xen on TCG
>>> - kvm_xen_guest.py runs Xen on KVM
>>> so both runs Xen guests.
>> 
>> Does boot_xen.py actually boot *Xen*? And presumably at least one Xen guest 
>> *within* Xen?
>
>I'll let Alex confirm, but yes, I expect Xen guest within Xen guest within 
>TCG. So the tags "accel:tcg" (already present) and "guest:xen".
>
>> kvm_xen_guest.py boots a "Xen guest" under KVM directly without any real Xen 
>> being present. It's *emulating* Xen.
>
>Yes, so the tag "guest:xen" is correct.
>
>> They do both run Xen guests (or at least guests which use Xen hypercalls and 
>> *think* they're running under Xen). But is that the important classification 
>> for lumping them together?
>
>The idea of AVOCADO_TAGS is to restrict testing to what you want to cover. So 
>here this allow running 'anything that can run Xen guest'
>in a single command, for example it is handy on my macOS aarch64 host.

Ok, that makes sense then. Thanks for your patience.

Reviewed-by: David Woodhouse <dwmw@xxxxxxxxxxxx>