Quoting Chris Wilson (2017-11-09 08:20:48) > When we close the VMA, we unbind it from the ppgtt and tear down the > page directory pointing at it. That may trigger us to return WC pages > back to the system, requiring conversion back to WB which itself may > sleep. That makes i915_vma_close() unsuitable for use inside the RCU > read lock, which we need to hold to iterate the radixtree. > > The fix is quite simple, we can close all the VMA as we close the ppgtt, > we only need to do that instead of closing them during destruction of > the LUT.
The flaw is that i915_vma_close() frees the vma; destroying our backpointer from the lut to the object. Definitely time for tea. :( -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/intel-gfx
