[PATCH 1/2] drm/ttm: unbind ttm before destroying node in accel move cleanup

[skeg...@gmail.com]

From: Ben Skeggs <bske...@redhat.com>

Nouveau makes the assumption that if a TTM is bound there will be a mm_node
around for it and the backwards ordering here resulted in a use-after-free
on some eviction paths.

Signed-off-by: Ben Skeggs <bskeggs at redhat.com>
---
 drivers/gpu/drm/ttm/ttm_bo_util.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c 
b/drivers/gpu/drm/ttm/ttm_bo_util.c
index 77dbf40..ae3c6f5 100644
--- a/drivers/gpu/drm/ttm/ttm_bo_util.c
+++ b/drivers/gpu/drm/ttm/ttm_bo_util.c
@@ -635,13 +635,13 @@ int ttm_bo_move_accel_cleanup(struct ttm_buffer_object 
*bo,
                if (ret)
                        return ret;

-               ttm_bo_free_old_node(bo);
                if ((man->flags & TTM_MEMTYPE_FLAG_FIXED) &&
                    (bo->ttm != NULL)) {
                        ttm_tt_unbind(bo->ttm);
                        ttm_tt_destroy(bo->ttm);
                        bo->ttm = NULL;
                }
+               ttm_bo_free_old_node(bo);
        } else {
                /**
                 * This should help pipeline ordinary buffer moves.
-- 
1.7.6