Re: [PATCH] radeon: fix front-buffer rendering

[Pierre W. <pi...@pi...>]

Ian Romanick schrieb:
> Joel Bosveld wrote:
>> This fixes rendering when using dri2 (so, that means, radeon-rewrite and
>> radeon-gem-cs) and a near-master xserver (the front-buffer changes). It
>> is mostly just copied from the changes to intel.
> 
> Strong work. :)
> 
> There's a bug in the Intel Mesa code, however.  Some cases of
> single-buffer rendering don't get is_front_buffer_rendering set.  I
> haven't tracked it down yet.  This manifests as a segfault in
> intel_region_buffer.  I don't know exactly how it will manifest in the
> Radeon drivers, but it will probably be similar.

In src/mesa/drivers/dri/intel/intel_buffers.c:327 only
mode==GL_FRONT_LEFT is checked, but everywhere else mode==GL_FRONT
implies using the same buffer as mode==GL_FRONT_LEFT (plus the buffer
for GL_FRONT_RIGHT). Checking for GL_FRONT makes the segfaults go away
for me.

Regards,
  Pierre