On Thu, Jun 20, 2013 at 01:27:14PM +0100, Chris Wilson wrote: > On Thu, Jun 20, 2013 at 01:29:10PM +0300, Ville Syrj?l? wrote: > > On Thu, Jun 20, 2013 at 10:14:36AM +0100, Chris Wilson wrote: > > > On Thu, Jun 20, 2013 at 11:17:16AM +0300, Ville Syrj?l? wrote: > > > > We already have a bit of pitch checking in intel_framebuffer_init(). > > > > In fact there's a FIXME about pre-ilk limits there. > > > > > > It looks tidier to fix that check. We still need to double check the > > > values though as the tiling mode is independent of the fb config and may > > > be changed by the user. > > > > True, some checking needs to be done after pinning. > > > > I guess we could have one function that has the checks, and just call it > > from both places. > > I'm thinking we note the tiling (and anything else of significance) > during framebuffer_init() and reject the set-base if the object changes. > I don't think any userspace depends upon being able to change the object > after AddFB, and I don't think we want to allow the fb/obj to so easily > become inconsistent. An alternative idea I've been tossing around is that we'd reject tiling changes while we have drm_framebuffers pointing at the object. So some kind of fb_refcount on the object. That would make buggy user space trip over a bit earlier. But either way seems reasonable to me. -- Ville Syrj?l? Intel OTC
