[PATCH v4 2/6] drm/i915: sanitize mem_flags for stolen buffers

[Robert Beckett]

Stolen regions are not page backed or considered iomem.
Prevent flags indicating such.
This correctly prevents stolen buffers from attempting to directly map
them.

See i915_gem_object_has_struct_page() and i915_gem_object_has_iomem()
usage for where it would break otherwise.

Signed-off-by: Robert Beckett <bob.beckett at collabora.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
index 358f8a1a30ce..9fe8132de3b2 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm_move.c
@@ -122,8 +122,9 @@ void i915_ttm_adjust_gem_after_move(struct drm_i915_gem_object *obj)
 
 	obj->mem_flags &= ~(I915_BO_FLAG_STRUCT_PAGE | I915_BO_FLAG_IOMEM);
 
-	obj->mem_flags |= i915_ttm_cpu_maps_iomem(bo->resource) ? I915_BO_FLAG_IOMEM :
-		I915_BO_FLAG_STRUCT_PAGE;
+	if (obj->mm.region->id != INTEL_REGION_STOLEN_SMEM)
+		obj->mem_flags |= i915_ttm_cpu_maps_iomem(bo->resource) ? I915_BO_FLAG_IOMEM :
+			I915_BO_FLAG_STRUCT_PAGE;
 
 	cache_level = i915_ttm_cache_level(to_i915(bo->base.dev), bo->resource,
 					   bo->ttm);
-- 
2.25.1