[Intel-gfx] [PATCH 1/2] drm/core: Preserve the framebuffer after removing it.

[Daniel Vetter]

On Wed, Sep 9, 2015 at 6:36 PM, Tvrtko Ursulin
<tvrtko.ursulin at linux.intel.com> wrote:
> I am not even going that far, just talking about last frame stuck on screen.
> For me making that easier is a regression.

So let's look at various systems:
- super-modern fbdev less system: logind keeps a dup of every
master-capabel drm fd. Compositor crashing won't ever result in
close() getting called since logind still has its copy. Cleanup needs
to be done manually anyway with the system compositor.
- Current systems: Compositor restarts and cleans up the mess we left behind.
- Greybeards who start X with startx: Those folks also have fbdev,
which will do the recover.

In the strictest sense the screen leaks for a bit. In practice no one
will ever notice, at least assuming I haven't missed a use-case. And
for regression it only counts as one if you can actually spot a
difference ;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch