From: Michel D?nzer <michel.daen...@amd.com>

entry->size is the size of the node, not the size of the hole after it.
So the code would actually find the hole which can satisfy the
constraints and which is preceded by the smallest node, not the smallest
hole satisfying the constraints.

Reported-by: "Huang, FrankR" <FrankR.Huang at amd.com>
Signed-off-by: Michel D?nzer <michel.daenzer at amd.com>
---

v2: Less invasive fix.

 drivers/gpu/drm/drm_mm.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/drm_mm.c b/drivers/gpu/drm/drm_mm.c
index a2d45b74..8b16a10 100644
--- a/drivers/gpu/drm/drm_mm.c
+++ b/drivers/gpu/drm/drm_mm.c
@@ -392,6 +392,8 @@ static struct drm_mm_node *drm_mm_search_free_generic(const 
struct drm_mm *mm,
        best_size = ~0UL;

        drm_mm_for_each_hole(entry, mm, adj_start, adj_end) {
+               unsigned long hole_size = adj_end - adj_start;
+
                if (mm->color_adjust) {
                        mm->color_adjust(entry, color, &adj_start, &adj_end);
                        if (adj_end <= adj_start)
@@ -404,9 +406,9 @@ static struct drm_mm_node *drm_mm_search_free_generic(const 
struct drm_mm *mm,
                if (!(flags & DRM_MM_SEARCH_BEST))
                        return entry;

-               if (entry->size < best_size) {
+               if (hole_size < best_size) {
                        best = entry;
-                       best_size = entry->size;
+                       best_size = hole_size;
                }
        }

@@ -433,6 +435,8 @@ static struct drm_mm_node 
*drm_mm_search_free_in_range_generic(const struct drm_
        best_size = ~0UL;

        drm_mm_for_each_hole(entry, mm, adj_start, adj_end) {
+               unsigned long hole_size = adj_end - adj_start;
+
                if (adj_start < start)
                        adj_start = start;
                if (adj_end > end)
@@ -450,9 +454,9 @@ static struct drm_mm_node 
*drm_mm_search_free_in_range_generic(const struct drm_
                if (!(flags & DRM_MM_SEARCH_BEST))
                        return entry;

-               if (entry->size < best_size) {
+               if (hole_size < best_size) {
                        best = entry;
-                       best_size = entry->size;
+                       best_size = hole_size;
                }
        }

-- 
1.9.0

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