[Mesa-dev] [PATCH 1/3] dri3_glx.c: Pass NULL DRI drawables into driver for None GLX drawables

[Zhang, Xiong Y]

 Hi Xiong Zhang,
> On 25 March 2015 at 08:05, Xiong Zhang <xiong.y.zhang at intel.com> wrote:
> > GLX_ARB_create_context spec says:
> > If either <draw> or <read> are not a valid GLX drawable, a
> > GLXBadDrawable error is generated, unless <draw> and <read> are both
> > None and the OpenGL version supported by <ctx> is 3.0 or greater.
> >
> > So when both <draw> and <read> are None, it could pass NULL drawable
> > into driver instead of returing GLXBadDrawable.
> >
> I'm a bit fresh in the area, but where do we check that the OpenGL version
> supported is 3.0 or greater ? Is there an assumption that all
> dri2/3 modules support it ?

[Zhang, Xiong Y] the patch lack of checking of OpenGL version >= 3.0, I will add it.
> 
> A similar commit has landed for dri2 in mesa 10.2 f658150639c(glx:
> Pass NULL DRI drawables into the DRI driver for None GLX drawables).
> Shouldn't a similar one be due for dri(1), drisw etc ? Not suggesting that you
> should prep one, just asking.
> 
[Zhang, Xiong Y] yes, Both patches resolve the same issues. I think it should be applied to
Dri(1), drisw also

> From a quick look - if it wasn't for indirect glx, most of these (and patch 2/3)
> changes could be pushed one level up to glxcurrent.c:MakeContextCurrent. Bit
> unfortunate about the duplication but that's another story.
>
[Zhang, Xiong Y] yes, I want to push these to top level also to reduce replicate code. But
There are two difficulties:
1. indirect glx and applegl glx are exception, they use a different bind() code structure as driX
2. Until call psc->core->bindContext(), we don't know whether glx_context is a bad context. And
Psc->core->bindContext() should be called in driX_bind_context. I mean patch 3 couldn't move
 To glxCurrent.c
 
> Cheers
> Emil