[PATCH 3.16 045/136] drm/ttm: once more fix ttm_buffer_object_transfer

[Ben Hutchings]

3.16.54-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Christian KÃnig <christian.koenig@xxxxxxx>

commit 4d98e5ee6084f6d7bc578c5d5f86de7156aaa4cb upstream.

When the mutex is locked just in the moment we copy it we end up with a
warning that we release a locked mutex.

Fix this by properly reinitializing the mutex.

Signed-off-by: Christian KÃnig <christian.koenig@xxxxxxx>
Reviewed-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
 drivers/gpu/drm/ttm/ttm_bo_util.c | 1 +
 1 file changed, 1 insertion(+)

--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -463,6 +463,7 @@ static int ttm_buffer_object_transfer(st
 	INIT_LIST_HEAD(&fbo->lru);
 	INIT_LIST_HEAD(&fbo->swap);
 	INIT_LIST_HEAD(&fbo->io_reserve_lru);
+	mutex_init(&fbo->wu_mutex);
 	drm_vma_node_reset(&fbo->vma_node);
 	atomic_set(&fbo->cpu_writers, 0);