From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D5267C3A589 for ; Thu, 15 Aug 2019 23:36:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AEDDB206C2 for ; Thu, 15 Aug 2019 23:36:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726329AbfHOXgu (ORCPT ); Thu, 15 Aug 2019 19:36:50 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:52260 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725440AbfHOXgu (ORCPT ); Thu, 15 Aug 2019 19:36:50 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 658A812651255; Thu, 15 Aug 2019 16:36:49 -0700 (PDT) Date: Thu, 15 Aug 2019 16:36:48 -0700 (PDT) Message-Id: <20190815.163648.1684648819390926444.davem@davemloft.net> To: sr@denx.de Cc: netdev@vger.kernel.org, opensource@vdorst.com, daniel@makrotopia.org, sean.wang@mediatek.com, john@phrozen.org Subject: Re: [PATCH net-next 4/4 v2] net: ethernet: mediatek: Add MT7628/88 SoC support From: David Miller In-Reply-To: <20190814111825.10855-4-sr@denx.de> References: <20190814111825.10855-1-sr@denx.de> <20190814111825.10855-4-sr@denx.de> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Thu, 15 Aug 2019 16:36:49 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Stefan Roese Date: Wed, 14 Aug 2019 13:18:25 +0200 > +static int txd_to_idx(struct mtk_tx_ring *ring, struct mtk_tx_dma *dma) > +{ > + return ((u32)dma - (u32)ring->dma) / sizeof(*dma); > +} This will definitely warn on 64-bit, and you should avoid that even if this driver can not possibly be built on 64-bit platforms. You cannot truncate a pointer to an integer which is potentially smaller in representation size than a pointer could potentially be. Just can avoid all of these issues by using real pointer arithmetic and casting to (char *), or even better, (void *).