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=-10.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=ham 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 228B3C4361B for ; Fri, 18 Dec 2020 10:44:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0AC423A5B for ; Fri, 18 Dec 2020 10:44:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389252AbgLRKoz (ORCPT ); Fri, 18 Dec 2020 05:44:55 -0500 Received: from mail.kernel.org ([198.145.29.99]:38434 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1733203AbgLRKoy (ORCPT ); Fri, 18 Dec 2020 05:44:54 -0500 Date: Fri, 18 Dec 2020 10:44:10 +0000 From: Catalin Marinas To: kernel test robot Cc: Ionela Voinescu , kbuild-all@lists.01.org, linux-kernel@vger.kernel.org, Sudeep Holla Subject: Re: arch/arm64/kernel/topology.c:367:22: sparse: sparse: dereference of noderef expression Message-ID: <20201218104410.GB5258@gaia> References: <202012180512.hxAiUO00-lkp@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <202012180512.hxAiUO00-lkp@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Dec 18, 2020 at 05:00:16AM +0800, kernel test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master > head: 74f602dc96dd854c7b2034947798c1e2a6b84066 > commit: 68c5debcc06d6d24f15dbf978780fc5efc147d5e arm64: implement CPPC FFH support using AMUs > date: 5 weeks ago > config: arm64-randconfig-s032-20201217 (attached as .config) > compiler: aarch64-linux-gcc (GCC) 9.3.0 > reproduce: > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > chmod +x ~/bin/make.cross > # apt-get install sparse > # sparse version: v0.6.3-184-g1b896707-dirty > # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=68c5debcc06d6d24f15dbf978780fc5efc147d5e > git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > git fetch --no-tags linus master > git checkout 68c5debcc06d6d24f15dbf978780fc5efc147d5e > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arm64 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot > > > "sparse warnings: (new ones prefixed by >>)" > >> arch/arm64/kernel/topology.c:367:22: sparse: sparse: dereference of noderef expression > > vim +367 arch/arm64/kernel/topology.c > > 362 > 363 int cpc_read_ffh(int cpu, struct cpc_reg *reg, u64 *val) > 364 { > 365 int ret = -EOPNOTSUPP; > 366 > > 367 switch ((u64)reg->address) { That's not a dereference but I guess sparse complains of dropping the __iomem. We could change the cast to (__force u64) to silence sparse. Thanks for the report. -- Catalin