4.8-stable review patch. If anyone has any objections, please let me know.
------------------ From: Ben Skeggs <bske...@redhat.com> commit 10dcab3e7f477bffee88d518aad57d06777cfdf4 upstream. TTM was changed a while back to allow for pipelining of buffer moves, and part of this was the removal of waiting for a BO to idle before calling move(), placing the responsibility on the driver to do this if required. That's all well and good, except, we make use of move_notify() to handle mapping/unmapping from the GPU VMM as move() isn't called on all paths. This commit adds a wait before unmapping from a VMM in move_notify(), to prevent GPU page faults where a buffer is still being accessed. Signed-off-by: Ben Skeggs <bske...@redhat.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/gpu/drm/nouveau/nouveau_bo.c | 1 + 1 file changed, 1 insertion(+) --- a/drivers/gpu/drm/nouveau/nouveau_bo.c +++ b/drivers/gpu/drm/nouveau/nouveau_bo.c @@ -1209,6 +1209,7 @@ nouveau_bo_move_ntfy(struct ttm_buffer_o nvbo->page_shift != vma->vm->mmu->lpg_shift)) { nvkm_vm_map(vma, new_mem->mm_node); } else { + WARN_ON(ttm_bo_wait(bo, false, false)); nvkm_vm_unmap(vma); } }