Where are framebuffers/visuals created?

[Bengt Ahlgren]

Greg V <greg at unrelenting.technology> writes:

> On Wed, Sep 26, 2018 at 4:32 PM, Bengt Ahlgren <bengt.ahlgren at ri.se>
> wrote:
>> I'd like to try to debug and find the cause of this issue with Kwin,
>> but
>> I don't know where in the graphics stack to start digging:
>>
>> https://mail.kde.org/pipermail/kde-freebsd/2018-April/027704.html
>>
>> In short, after an update of Mesa, Kwin complained about not finding
>> the
>> appropriate framebuffer, and refused doing compositing with opengl.
>>
>> So, my question is: where in the graphics stack are the
>> framebuffers/visuals created?
>
> Looks like a somewhat common issue with KWin, people have had it with
>
> - Xinerama enabled on Nvidia:
> https://bbs.archlinux.org/viewtopic.php?id=123715
> - Dual GPU laptops: https://bugs.kde.org/show_bug.cgi?id=323134
>
> And this 32-bit requirement was dropped in KWin:
> https://git.reviewboard.kde.org/r/126262/
> But that fix is probably only in Plasma5, not KDE4. (Time to drop
> KDE4! ;))

Thanks for the pointer - I'll have a look at that fix!

> Have you tried modesetting DDX (w/ glamor acceleration) instead of the
> (terrible) intel DDX?
> Just deleting the intel driver should accomplish that, but just in
> case, manual xorg.conf config looks like:
>
> Section "Device"
>    Identifier  "GPU"
>    Driver      "modesetting"
>    Option      "AccelMethod"    "glamor"
> EndSection

Yes, I tried - no difference in this regard.  The modsetting driver
results in some artifacts, e.g. on window decorations, on my laptop
(Intel Ironlake), so I'll stick with the Intel driver.

Bengt