In the next few patches, we will depend upon there being no
uninitialised bits inside the ggtt_view. To ensure this we add the
__packed attribute and double check with a build bug that gcc hasn't
expanded the struct to include some padding bytes.

Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursu...@intel.com>
---
 drivers/gpu/drm/i915/i915_gem_gtt.h | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_gtt.h 
b/drivers/gpu/drm/i915/i915_gem_gtt.h
index 5dd3755a5a45..57cbd532dae1 100644
--- a/drivers/gpu/drm/i915/i915_gem_gtt.h
+++ b/drivers/gpu/drm/i915/i915_gem_gtt.h
@@ -156,12 +156,22 @@ struct intel_rotation_info {
                /* tiles */
                unsigned int width, height, stride, offset;
        } plane[2];
-};
+} __packed;
+
+static inline void assert_intel_rotation_info_is_packed(void)
+{
+       BUILD_BUG_ON(sizeof(struct intel_rotation_info) != 8*sizeof(unsigned 
int));
+}
 
 struct intel_partial_info {
        u64 offset;
        unsigned int size;
-};
+} __packed;
+
+static inline void assert_intel_partial_info_is_packed(void)
+{
+       BUILD_BUG_ON(sizeof(struct intel_partial_info) != sizeof(u64) + 
sizeof(unsigned int));
+}
 
 struct i915_ggtt_view {
        enum i915_ggtt_view_type type;
-- 
2.11.0

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