[Libguestfs] [virt-v2v wave 2 PATCH v1 03/16] output: handle Standard_VGA in the OpenStack format

[Laszlo Ersek]

Hi Kashyap,

On 11/15/21 14:54, Kashyap Chamarthy wrote:
> On Sat, Nov 13, 2021 at 11:29:46PM +0100, Laszlo Ersek wrote:
>> Convert the Standard_VGA value of "guestcaps.gcaps_video" to the string
>> "vga", in the OpenStack image properties.
> 
> Hi,
> 
> Your patch reminds me that I neglected to update upstream Glance
> documentation to add "bochs" video model when I added support for it [1]
> in Nova.  So I just submitted[2] a docs patch to Glance to rectify that.
> 
> Thanks for the reminder. :-)
> 
> 
> [1] https://opendev.org/openstack/nova/commit/c590843974 (Allow 'bochs'
>     as a display device option)
> [2] https://review.opendev.org/c/openstack/glance/+/817950 (Add "bochs"
>     as a possible video model)
> 
> 
>> Reference:
>> https://docs.openstack.org/glance/xena/admin/useful-image-properties.html
>>
>> Cc: Kashyap Chamarthy <kchamart at redhat.com>
>> Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1961107
>> Signed-off-by: Laszlo Ersek <lersek at redhat.com>
>> ---
>>
>> Notes:
>>     v1:
>>     
>>     - new in v1
>>
>>  output/openstack_image_properties.ml | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/output/openstack_image_properties.ml b/output/openstack_image_properties.ml
>> index 72f3e9d9261d..9d466ecfbf0f 100644
>> --- a/output/openstack_image_properties.ml
>> +++ b/output/openstack_image_properties.ml
>> @@ -43,7 +43,7 @@ let create source inspect { target_buses; guestcaps; target_firmware } =
>>       | RTL8139 -> "rtl8139");
>>      "hw_video_model",
>>      (match guestcaps.gcaps_video with
>> -     | Standard_VGA -> assert false
>> +     | Standard_VGA -> "vga"
>>       | QXL -> "qxl"
>>       | Cirrus -> "cirrus");
> 
> Please also add an entry for "bochs" video model.

That is not useful for us in this BZ / patch series. The purpose of
virt-v2v here is that the converted domain start with *some* usable
video device. After discussing the potential options with Gerd at length
(especially based on his blog post), it became clear that VGA was the
best choice -- smaller attack surface than QXL, performance-wise just as
fine for the above-stated virt-v2v purpose, and universally recognized
by all guests we care about. Therefore VGA replaces QXL and also the
older (compat) Cirrus. The whole idea is to simplify / unify as much as
possible.

Adding a mapping for Bochs is not useful here, as virt-v2v will not
intend (in the foreseeable future) to produce such output (= converted)
domains. Once the converted domain lives in OpenStack, the admin can
easily change the video device, but that's beyond virt-v2v's mandate.

> 
> With that amended, FWIW:
> 
>     Reviewed-by: Kashyap Chamarthy <kchamart at redhat.com>    

So, can I take your R-b only for the correctness of "vga"?
("Completeness", with regard to Bochs for example, is not a goal here,
again.)

Thank you!
Laszlo

> 
>>      "hw_machine_type",
>> -- 
>> 2.19.1.3.g30247aa5d201
>>
>>
>