Bug#981722: DRM: Segfault on Etnaviv

[Simon McVittie]

On Wed, 03 Feb 2021 at 09:56:21 +0100, Guido Günther wrote:
> SDL2 currently segfaults on imx8 hardware with the DRM backend when trying to
> use osk-sdl (currenty in NEW) when trying to use a cursor plane (so
> other applications should hit this as well)

The KMSDRM backend is quite new and I suspect none of the maintainers
either upstream or in Debian use it (X11 or Wayland are a lot more
interesting for most SDL users), so if it works, that's lucky, and if
it doesn't work, we are not really well-placed to resolve that.

> The buster version works

With which backend? I didn't think we had KMSDRM enabled until August 2020?
(Unfortunately I can't find the bug report or merge request that asked for
it to be enabled.)

> and above changes were reverted in
> current hg so 2.0.15 is working as well but a backport is non trivial
> since most of the code there got rolled back so backporting that would
> be rather invasive.

If you can prepare a tested patch, I'd consider it: hopefully the changes
would be isolated to KMSDRM files and so could not cause regressions for
X11 or Wayland?

Or, if the KMSDRM backend doesn't actually work in its current state, we
could disable it to stop it from making people think it ought to work?

If this functionality is important to you, an autopkgtest would also be
welcome, although I realise that probably isn't feasible because it would
need to be run on suitable (real or virtual) hardware.

    smcv