mesa/progs/xdemo/texture_from_pixmap crashes xserver on 2nd run

[Pierre Willenbrock]

Hi again,

Pierre Willenbrock schrieb:
> Hi list,
> 
> while trying to find out why kwin of kde4 does only display a black
> screen when using opengl compositing, i wanted to check if the texture
> from pixmap gl extension works. For that, i modified
> mesa/progs/xdemo/texture_from_pixmap to ignore the missing bits of the
> fbconfigs, and ran it. Showed the correct image for the first run, but
> crashed the xserver on the second run(same xserver).
> 
> I am using git master of drm, mesa, xserver, xf86-video-intel.
> 
> Valgrinding X results in these errors(after the usual uninitialised
> ioctls/jumps in bios code):
> 
> ==7683== Invalid read of size 4
> ==7683==    at 0x4933923: __glXDRIleaveServer (glxdri.c:131)
> ==7683==    by 0x48FD94B: __glXleaveServer (glxext.c:442)
> ==7683==    by 0x48FDEB9: __glXDispatch (glxext.c:488)
> ==7683==    by 0x808A618: Dispatch (dispatch.c:468)
> ==7683==    by 0x8071134: main (main.c:448)
> ==7683==  Address 0x194c26d0 is 72 bytes inside a block of size 88 free'd
> ==7683==    at 0x402398C: free (in
> /usr/lib/valgrind/x86-linux/vgpreload_memcheck.so)
> ==7683==    by 0x8130B10: Xfree (utils.c:1451)
> ==7683==    by 0x4933C57: __glXDRIdrawableDestroy (glxdri.c:199)
> ==7683==    by 0x48FF2A6: __glXUnrefDrawable (glxutil.c:136)
> ==7683==    by 0x48FDD7A: DrawableGone (glxext.c:112)
> ==7683==    by 0x8073538: FreeClientResources (resource.c:812)
> ==7683==    by 0x80842C8: CloseDownClient (dispatch.c:3689)
> ==7683==    by 0x808A641: Dispatch (dispatch.c:479)
> ==7683==    by 0x8071134: main (main.c:448)

the attached patch makes this go away, but it is a bit clumsy. The
problem is, the pDraw-member of the drawable is already NULLed, so i see
no other way to get to the screen at that point.

Regards,
  Pierre
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