Comment # 18 on bug 1005323 from Antonio Larrosa

Finally I could reproduce the Qt webengine crashes with akregator (thanks Max
for pointing that out) and I could test my qt webengine patch. The patch
disabled the use of the GPU by the library (it sets an internal disableGpu
variable to true). There's another internal flag called
EnableThreadedCompositing, but it seems only disabling threaded compositing
isn't enough to fix the crashes. So the way I see it, we have two options:

1) Patch kwin so that it defaults to XRender and patch Qt webengine so it
disables the use of the GPU (both only with nouveau, of course). That would fix
kwin and all kde applications using the library while other applications would
be able to use it. I understand that breaks the experience for people that have
a graphics card that works fine with nouveau, but option 2 breaks it equally
and this feels to me less intrusive.

Option 1.5 would be to allow setting an USE_NOUVEAU_GPU_I_KNOW_WHAT_I_AM_DOING
environment variable to "disable" the patches and allow people to test their
hardware and report working cards to us so we can create a cards whitelist that
is read by kwin and qtwebengine, and that we can update via a (new)
"nouveau-whitelist" package updated regularly. So at some point in the future,
people with working cards will just feel their desktop is faster after they
update their systems.

2) Disable the Nouveau 3D/DRI driver in Leap as it's currently done and try to
get upstream to fix it. This, indeed it's much easier for us, as people will
just see bad performance and switch to the propietary nvidia drivers.

I'm not sure which option I prefer. I think I like option 1 (or 1.5) more, but
option 2 doesn't look bad either (and is, in fact, much easier for us).
Opinions?