Libguestfs - Feb 2019 - Re: virt-v2v: default graphics driver for SUSE guests

Hi Mike,

in 2013 you added the support for SUSE guests in the old virt-v2v (the
one written in Perl); the commit doing it is attached, since the old
virt-v2v was hosted on fedorahosted.org, which is no more.
As part of that change, the default graphics driver was changed to be
cirrus for SUSE guests, and qxl (as before) for any other.

When Rich Jones rewrote virt-v2v in 2014 in OCaml, he kept the same
logic [1]; this is still there today [2], and none of the other
SUSE-related changes that were done (mostly by another SUSE guy,
Cédric Bosdonnat) changed that in any way.

My question is: is using cirrus still the best choice for SUSE guests?
If not, what about using qxl as well, as done for any non-SUSE guest?
(We can also do that depending on the version of the guest, in case
only newer SUSE versions work fine with qxl).

[1]
https://github.com/libguestfs/libguestfs/commit/3d1cb74b3eee51c5d015032ad964892be914ea9c
[2]
https://github.com/libguestfs/libguestfs/blob/master/v2v/convert_linux.ml#L774

Thanks,
-- 
Pino Toscano

Hi Pino,

On 2/21/19 3:07 AM, Pino Toscano wrote:
> in 2013 you added the support for SUSE guests in the old virt-v2v (the
> one written in Perl); the commit doing it is attached, since the old
> virt-v2v was hosted on fedorahosted.org, which is no more.
> As part of that change, the default graphics driver was changed to be
> cirrus for SUSE guests, and qxl (as before) for any other.
Ah, yes! I remember fighting through that process...  ;)
> When Rich Jones rewrote virt-v2v in 2014 in OCaml, he kept the same
> logic [1]; this is still there today [2], and none of the other
> SUSE-related changes that were done (mostly by another SUSE guy,
> Cédric Bosdonnat) changed that in any way.
>
> My question is: is using cirrus still the best choice for SUSE guests?
> If not, what about using qxl as well, as done for any non-SUSE guest?
> (We can also do that depending on the version of the guest, in case
> only newer SUSE versions work fine with qxl).
At the time of my commit, we had to use cirrus. However, I believe all
the currently supported SUSE versions should now work with qxl. Let me
verify that, and hopefully the exception can be removed.

Thanks for reaching out, and I'll be in touch as soon as I've got a more
complete answer.

Best,
Mike

Hi Pino,

On 2/26/19 5:52 PM, Mike Latimer wrote:
> On 2/21/19 3:07 AM, Pino Toscano wrote:
>> My question is: is using cirrus still the best choice for SUSE guests?
>> If not, what about using qxl as well, as done for any non-SUSE guest?
>> (We can also do that depending on the version of the guest, in case
>> only newer SUSE versions work fine with qxl).
> At the time of my commit, we had to use cirrus. However, I believe all
> the currently supported SUSE versions should now work with qxl. Let me
> verify that, and hopefully the exception can be removed.
After a bit of checking, defaulting to qxl for SUSE guests is a better
choice, and should work fine for all versions we expect to encounter in
the wild. Do you mind pulling this out yourself, or would you prefer I
submit a patch containing this change? I've moved on to other things,
and really only have enough bandwidth for a minimal change like:

diff -Nurp a/v2v/convert_linux.ml b/v2v/convert_linux.ml
--- a/v2v/convert_linux.ml    2019-02-28 16:30:58.668800431 -0700
+++ b/v2v/convert_linux.ml    2019-02-28 16:33:14.729907825 -0700
@@ -104,7 +104,7 @@ let convert (g : G.guestfs) inspect sour
 
     let video        match rcaps.rcaps_video with
-      | None -> get_display_driver ()
+      | None -> QLX
       | Some video -> video in
 
     let block_type @@ -771,9 +771,6 @@ let convert (g : G.guestfs) inspect sour
     else
       true
 
-  and get_display_driver () -    if family = `SUSE_family then Cirrus else QXL
-
   and configure_display_driver video      let video_driver = match video with
QXL -> "qxl" | Cirrus ->
"cirrus" in

I'd be happy to submit this as an official patch, or just let you do it
with some of your planned changes.

Thanks!
Mike