bb4aa8a3ea
When importing a BO, if it is already imported, then the handle will alias an existing BO instance. It is possible for the existing owner to free the BO after the import and leave a dangling handle before we get a chance to increase the refcount, so we need to lock the BO table mutex before importing, to make sure nobody else goes through the free path during that window. Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com> Signed-off-by: Asahi Lina <lina@asahilina.net> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20403>