[PATCH] drm/i915: Fix comparison bug

[Rasmus Villemoes <linux@rasmusvillemoes.dk>]

->stolen->start has type unsigned long; relying on the difference
(effectively cast to int) for sorting is wrong.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
---
 drivers/gpu/drm/i915/i915_debugfs.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index 063b44817e08..adfb863bb580 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -236,7 +236,11 @@ static int obj_rank_by_stolen(void *priv,
 	struct drm_i915_gem_object *b =
 		container_of(B, struct drm_i915_gem_object, obj_exec_link);
 
-	return a->stolen->start - b->stolen->start;
+	if (a->stolen->start < b->stolen->start)
+		return -1;
+	if (a->stolen->start > b->stolen->start)
+		return 1;
+	return 0;
 }
 
 static int i915_gem_stolen_list_info(struct seq_file *m, void *data)
-- 
2.1.3