when allocating a resource in place it is common to free the buffer's resource, then allocate a new resource in a different placement. e.g. amdgpu_bo_create_kernel_at calls ttm_resource_free, then calls ttm_bo_mem_space. In this situation, bo->resource will be null as it is cleared during the initial freeing of the previous resource. This leads to a null deref. Fixes: d3116756a710 (drm/ttm: rename bo->mem and make it a pointer) Signed-off-by: Robert Beckett <bob.beckett@xxxxxxxxxxxxx> --- drivers/gpu/drm/ttm/ttm_bo.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c index db3dc7ef5382..62b29ee7d040 100644 --- a/drivers/gpu/drm/ttm/ttm_bo.c +++ b/drivers/gpu/drm/ttm/ttm_bo.c @@ -875,7 +875,7 @@ int ttm_bo_mem_space(struct ttm_buffer_object *bo, } error: - if (bo->resource->mem_type == TTM_PL_SYSTEM && !bo->pin_count) + if (bo->resource && bo->resource->mem_type == TTM_PL_SYSTEM && !bo->pin_count) ttm_bo_move_to_lru_tail_unlocked(bo); return ret; -- 2.25.1
