The code was making a copy of a struct ttm_resource. However, recently the struct ttm_resources were allowed to be subclassed and also were allowed to be malloced, hence the driver could end up assuming the copy we handed it was subclassed and worse, the original could have been freed at this point.

Fix this by using the original struct ttm_resource before it is potentially freed in ttm_bo_move_sync_cleanup()

v2: Base on drm-misc-next-fixes rather than drm-tip.

Reported-by: Ben Skeggs skeggsb@gmail.com Reported-by: Dave Airlie airlied@gmail.com Cc: Christian König christian.koenig@amd.com Fixes: 3bf3710e3718 ("drm/ttm: Add a generic TTM memcpy move for page-based iomem") Signed-off-by: Thomas Hellström thomas.hellstrom@linux.intel.com Reviewed-by: Christian König christian.koenig@amd.com Reviewed-by: Ben Skeggs bskeggs@redhat.com --- drivers/gpu/drm/ttm/ttm_bo_util.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/ttm/ttm_bo_util.c b/drivers/gpu/drm/ttm/ttm_bo_util.c index 763fa6f4e07d..1c5ffe2935af 100644 --- a/drivers/gpu/drm/ttm/ttm_bo_util.c +++ b/drivers/gpu/drm/ttm/ttm_bo_util.c @@ -143,7 +143,6 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo, struct ttm_resource *src_mem = bo->resource; struct ttm_resource_manager *src_man = ttm_manager_type(bdev, src_mem->mem_type); - struct ttm_resource src_copy = *src_mem; union { struct ttm_kmap_iter_tt tt; struct ttm_kmap_iter_linear_io io; @@ -173,11 +172,11 @@ int ttm_bo_move_memcpy(struct ttm_buffer_object *bo, }

ttm_move_memcpy(bo, dst_mem->num_pages, dst_iter, src_iter); - src_copy = *src_mem; - ttm_bo_move_sync_cleanup(bo, dst_mem);

if (!src_iter->ops->maps_tt) - ttm_kmap_iter_linear_io_fini(&_src_iter.io, bdev, &src_copy); + ttm_kmap_iter_linear_io_fini(&_src_iter.io, bdev, src_mem); + ttm_bo_move_sync_cleanup(bo, dst_mem); + out_src_iter: if (!dst_iter->ops->maps_tt) ttm_kmap_iter_linear_io_fini(&_dst_iter.io, bdev, dst_mem);