On Fri, Jan 22, 2016 at 04:33:18PM +0000, Tvrtko Ursulin wrote: > I was confused by the current code which does the reset after unpinning: > > ... > i915_gem_reset(dev); > > simulated = dev_priv->gpu_error.stop_rings != 0; > > ret = intel_gpu_reset(dev); > ... > > > What is right then?
Yeah, it would be better to do the sw reset after the hw reset so that the GPU is a known state when we tear down everything. > Sounds bad to be unpinning with the GPU in unknown state. But > obviously it has been like this for who knows how long. So I have no > idea. :( i915_reset() is only called on a hung GPU, and I expect we simply haven't stressed the system enough with an active-vs-hung pair of engines to be able to see stray writes and whatnot. The downside is that if we jiggle the i915_gem_reset() we have to ask the awkward question of what to do with state when reset fails? We should keep it around because the hw state is unknown - but that can be a significant amount of memory trapped. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
