[PATCH xserver] modesetting: Fix page flipping under DRI 3.2.

[Daniel Stone]

Hi Mario,

On 3 April 2018 at 15:44, Mario Kleiner <mario.kleiner.de at gmail.com> wrote:
> Those are fine according to my testing, they fix mode-setting under
> both depth24 and 30.
>
> However as testing shows, still not sufficient for pageflipping if the
> kms driver doesn't support full atomic (as tested on radeon-kms, and
> as well under nouveau-kms without the nouveau.atomic=1 kernel boot
> parameter). Even with atomic (nouveau.atomic=1, or intel-kms)
> pageflipping doesn't get used when it should be if the driver exposes
> num_modifiers==0, e.g., Intel Ivybridge under Linux 4.13 (whereas
> Linux 4.15-something was fine under Intel).
>
> The following snippet made pageflipping work on radeon-kms, intel-kms
> (Tested Linux 4.13 and some slightly outdated drm-next), nouveau-kms
> with/without nouveau.atomic=1 module parameter. I can turn it into a
> proper patch later today:

Thanks for tracking this down! That looks like the right thing to do,
modulo the obvious debug lines.

Cheers,
Daniel