Libguestfs - Sep 2022 - another GTK3 regression...

On 09/28/22 19:02, Daniel P. Berrang? wrote:
> On Wed, Sep 28, 2022 at 02:01:11PM +0200, Laszlo Ersek wrote:
>> (this reproduces at commit 0687cea6a86e; IOW the regression is not from
>> the recent GTK-related patches, but due to building p2v with GTK3. as
>> opposed to GTK2)
>>
>> In the first dialog, when the Test Connection button is clicked, a
>> spinner is supposed to be shown to the left, while p2v communicates via
>> v2v over ssh. This spinner is seen when running virt-p2v directly, but
>> not when running virt-p2v from a VM (using either a Live CD, or the
>> "run-virt-p2v-in-a-vm" makefile target).
>>
>> This difference is not seen when virt-p2v is built with GTK2; in that
>> case, *both* scenarios (direct & VM) show the spinner properly.
>>
>> I don't have an idea what the cause is. I vaguely suspect it could
be
>> related to the windowing environment (window manager) in use. It pretty
>> much looks like a GTK3 bug to me; whatever the windowing environment,
>> the spinner should either be there or not. (It's possible that we
have a
>> virt-p2v bug, of course, but why isn't the symptom consistent then?
GTK3
>> should not have a dependency at all on the Window Manager.)
> 
> There certainly are dependancies on both the window manager, and the
> desktop system (X11 vs wayland). There's a huge set of features that
> widget toolkits can negotiate with window managers,  and each window
> manager supports a different set of extensions, just one example
> being support for client side window decorations. In theory GTK should
> adapt to expose the same functionality to users whereever possible but
> there are certainly edge cases where this doesn't work, and bugs will
> certainly be present for more obscure combinations like X11 + any non
> mainstream window manager.
> 
> It is also not surprising to see a differnce from GTK2 to 3, as it
> radically changed under the hood, most notably with native Wayland
> support.
Very good points, thanks.

The tricky question is why the spinner works fine (using GTK3) in my
quite-non-standard environment (namely, forwarding X11 over ssh to my
local IceWM environment), but does not work in the Live VM environment,
which should be identical (including the Window Manager, if any) for
Rich and myself. IOW the discrepancy does not manifest itself where the
environments are obviously different, but it shows where the
environments appear more uniform.

I've got two ideas:

- Build and ISO (using my current env) for Rich to try out. (It seems
impossible that Rich will see the spinner that I *don't* see, booting
the same ISO image in a VM; but who knows?)

- Upgrade my environment (both my v2v development workstation, and the
livecd-creator VM) to Fedora 36, and retest.

I'll follow up.

Thanks
Laszlo

On 09/29/22 11:27, Laszlo Ersek wrote:
> The tricky question is why the spinner works fine (using GTK3) in my
> quite-non-standard environment (namely, forwarding X11 over ssh to my
> local IceWM environment), but does not work in the Live VM environment,
> which should be identical (including the Window Manager, if any) for
> Rich and myself. IOW the discrepancy does not manifest itself where the
> environments are obviously different, but it shows where the
> environments appear more uniform.
It gets worse.

I've determined (using the XTerm button in the first dialog) that in the
LiveCD environment, the gtk3 version is "gtk3-3.24.30-4.fc35.x86_64"
<https://koji.fedoraproject.org/koji/buildinfo?buildID=1837672>, from
"27 Sep 2021". This build is tagged "f35".

More recent builds exist, tagged as "f35-updates", but livecd-creator
does not pull them in.

Therefore, it seems that livecd-creator does not use the
"fedora-updates" repo, only the base "fedora" repo.

So I got (transitorily) happy -- I had found the bug! We'd *just* need
to make livecd-creator honor the "fedora-updates" repository!

Unfortunately, that won't suffice. Namely, I've also checked the gtk3
version in the VM that's launched by the command

  make run-virt-p2v-in-a-vm

using the same XTerm + "rpm -q" method.

Here, I do get "gtk3-3.24.34-1.fc35.x86_64"
<https://koji.fedoraproject.org/koji/buildinfo?buildID=1968341>, which
is the latest build -- from "fedora-updates".

And this exact same gtk3 version (3.24.34-1.fc35.x86_64) works well,
concerning the spinner, when I launch

  make run-virt-p2v-directly

!

But it does not work when I launch

  make run-virt-p2v-in-a-vm

In other words, *even though* livecd-creator uses an outdated gtk3
version (due to ignoring the "fedora-updates" repository for some
reason), the bug I'm witnessing is not due to that problem; that is,
it's not something affecting

  gtk3-3.24.30-4.fc35.x86_64

but fixed in

  gtk3-3.24.34-1.fc35.x86_64

Because, the latter still misbehaves in "run-virt-p2v-in-a-vm".

With that in mind, I'm going to claim that the same bug reproduces with
the earlier

  gtk3-3.24.30-4.fc35.x86_64

that's built into the ISO by livecd-creator, and therefore the ISO
should be good enough for Rich to please try out:
> I've got two ideas:
> 
> - Build and ISO (using my current env) for Rich to try out. (It seems
> impossible that Rich will see the spinner that I *don't* see, booting
> the same ISO image in a VM; but who knows?)
http://lacos.interhost.hu/livecd-p2v-202209291608-gitc213ae00a337.iso

(built at c213ae00a337)

sha256: f3a149aeab0179213d74bb1eac30d5d6f807d4c9cf3a548667903d5434d5699a

Thanks!
Laszlo
> - Upgrade my environment (both my v2v development workstation, and the
> livecd-creator VM) to Fedora 36, and retest.
> 
> I'll follow up.