From: Imre Deak Date: Fri, 22 Mar 2013 21:10:44 +0000 (+0200) Subject: drm/i915: set dummy page for stolen objects X-Git-Url: http://drtracing.org/?a=commitdiff_plain;h=5bd4687e57bbacec20930f580d025aee9fa1f4d8;p=deliverable%2Flinux.git drm/i915: set dummy page for stolen objects This is needed since currently sg_for_each_page assumes that we have a valid page in each sg item. It is only a real problem for CONFIG_SPARSEMEM where the page is dereferenced, in other cases the iterator works ok with an invalid page pointer. We can remove this workaround when we have fixed sg_page_iter to work on scatterlists without backing pages. Signed-off-by: Imre Deak --- diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c index 69d97cbac13c..efaaba5c4194 100644 --- a/drivers/gpu/drm/i915/i915_gem_stolen.c +++ b/drivers/gpu/drm/i915/i915_gem_stolen.c @@ -222,8 +222,8 @@ i915_pages_create_for_stolen(struct drm_device *dev, } sg = st->sgl; - sg->offset = offset; - sg->length = size; + /* we set the dummy page here only to make for_each_sg_page work */ + sg_set_page(sg, dev_priv->gtt.scratch_page, size, offset); sg_dma_address(sg) = (dma_addr_t)dev_priv->mm.stolen_base + offset; sg_dma_len(sg) = size;