Author: Kulikov Vasiliy <segooon@gmail.com> ‘cnt’ is unsigned, so this code may become wrong in future as dmatest_add_threads() can return error code: cnt = dmatest_add_threads(dtc, DMA_MEMCPY); thread_count += cnt > 0 ? cnt : 0; ^^^^^^^ Now it can return only -EINVAL if and only if second argument of dmatest_add_threads() is not one of DMA_MEMCPY, DMA_XOR, …