drm/ttm: Fix spinlock imbalance

commit a8ff3ee211fccf708e1911bbc096625453ebf759 upstream.

This imbalance may cause hangs when TTM is trying to swap out a buffer
that is already on the delayed delete list.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 0bb0f5f..0d27bff 100644 (file)
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -1816,6 +1816,7 @@ static int ttm_bo_swapout(struct ttm_mem_shrink *shrink)
                        spin_unlock(&glob->lru_lock);
                        (void) ttm_bo_cleanup_refs(bo, false, false, false);
                        kref_put(&bo->list_kref, ttm_bo_release_list);
+                       spin_lock(&glob->lru_lock);
                        continue;
                }