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=-11.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable 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 54456C432BE for ; Tue, 10 Aug 2021 11:34:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 326B96101E for ; Tue, 10 Aug 2021 11:34:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238332AbhHJLec (ORCPT ); Tue, 10 Aug 2021 07:34:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:49968 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229527AbhHJLeb (ORCPT ); Tue, 10 Aug 2021 07:34:31 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 40E386101E; Tue, 10 Aug 2021 11:34:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628595249; bh=U4Zld7mAu6v7/9xMDyWvpT/NNYAWTiUJU4He5dD/eL4=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=lJZtsLaj7jaRkxeJSZpFbApjAOcERUr6k3R9FD36dUPQtws4z6KYPDzXzDfxVdwp+ I4Rx380OJYH4+KsXFBVtVm/uNG5+BdcR8Ahwh6jgjxh0K/tABjGp27T2Hg8JZBXE66 8vBTJdpdvoQehoE9FCEvW0W8q/WWprPCty3ERtdmGnbv+mapiDKrWvnX8QiMmTnYa2 eYoAva5zQNUQpGzDJ8+QTXuMJ98dyx8tkIJ3Dt2Fuj9PHNrLQFBRSE/kIXBj0GOi3Z 1go5tRWI2r6aELq/bjZcQ5B37g3vK98ee8qExwrQ3Eb4Nk0uOW3E9PugjHiPxx5cBQ drvvS5gCGI1tg== Received: by mail-wr1-f54.google.com with SMTP id i4so8337645wru.0; Tue, 10 Aug 2021 04:34:09 -0700 (PDT) X-Gm-Message-State: AOAM5305gi1q9rTqsanlIG5ZRWYeUAyZc58HNcj3DqN4dPj1uy6WfPms 1x7VI5hCJVipRmNQey0KM6Dgbqvl+ToDS2hZJIs= X-Google-Smtp-Source: ABdhPJyjNp84V0PWdniYskkVm3tgBt8qm+LU5nYRyMlh1QdiRB65+ZJ6dm/n9ev4DK0S0p/m2pg884gI41cWjwdHPfc= X-Received: by 2002:adf:a309:: with SMTP id c9mr12971585wrb.99.1628595247894; Tue, 10 Aug 2021 04:34:07 -0700 (PDT) MIME-Version: 1.0 References: <5e8dfbd2-a6c0-6d02-53e9-1f29aebcc44e@huawei.com> In-Reply-To: From: Arnd Bergmann Date: Tue, 10 Aug 2021 13:33:52 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [GIT PULL 1/2] asm-generic: rework PCI I/O space access To: John Garry Cc: Linus Torvalds , linux-arch , linux-pci , Linux Kernel Mailing List , Niklas Schnelle Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Aug 10, 2021 at 11:19 AM John Garry wrote: > On 04/08/2021 09:52, Arnd Bergmann wrote: > > This seems a reasonable approach. Do you have a plan for this work? Or > still waiting for the green light? I'm rather busy with other work at the moment, so no particular plans for any time soon. > I have noticed the kernel test robot reporting the following to me, > which seems to be the same issue which was addressed in this series > originally: > > config: s390-randconfig-r032-20210802 (attached as .config) > compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project > 4f71f59bf3d9914188a11d0c41bedbb339d36ff5) > ... > All errors (new ones prefixed by >>): > > In file included from drivers/block/null_blk/main.c:12: > In file included from drivers/block/null_blk/null_blk.h:8: > In file included from include/linux/blkdev.h:25: > In file included from include/linux/scatterlist.h:9: > In file included from arch/s390/include/asm/io.h:75: > include/asm-generic/io.h:464:31: warning: performing pointer > arithmetic on a null pointer has undefined behavior > [-Wnull-pointer-arithmetic] > val = __raw_readb(PCI_IOBASE + addr); > > So I imagine lots of people are seeing these. Right, this is the original problem that Niklas was trying to solve. If Niklas has time to get this fixed, I can probably find a way to work with him on finishing up my proposed patch with the changes you suggested. Arnd