Comment # 20 on bug 91704 from Andy Furniss

(In reply to Christian König from comment #19)
> Nice catch!
> 
> And Andy is right this could explain some of the problem we had with VDPAU
> interop as well, cause there the device is also opened from multiple sides
> at the same time.

New version of the patch seems good for startx.

Also tried harder than yesterday with vdpau interop and it also seems good.