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 D114DC83004 for ; Wed, 29 Apr 2020 07:42:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AEC9E2083B for ; Wed, 29 Apr 2020 07:42:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726760AbgD2HmZ (ORCPT ); Wed, 29 Apr 2020 03:42:25 -0400 Received: from mout.kundenserver.de ([212.227.126.130]:59929 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726554AbgD2HmX (ORCPT ); Wed, 29 Apr 2020 03:42:23 -0400 Received: from mail-qt1-f169.google.com ([209.85.160.169]) by mrelayeu.kundenserver.de (mreue012 [212.227.15.129]) with ESMTPSA (Nemesis) id 1Mx0VH-1jEmjV0fTn-00ySHt; Wed, 29 Apr 2020 09:42:22 +0200 Received: by mail-qt1-f169.google.com with SMTP id b1so1117838qtt.1; Wed, 29 Apr 2020 00:42:21 -0700 (PDT) X-Gm-Message-State: AGi0PuYMx5cbpuTZKzYOJvRyKo4AlymN5WrSecm0QOs1GfFxiWKpzBCs 4TqODyDtwHxrCIrooQoHWMN+OsCU2EbxIlvnbtA= X-Google-Smtp-Source: APiQypJpUvYWo2LU3ZngNQ2JW3D6wR/VR7VqZhY2dctva2ZkWquiJEYUHe1E74mkf1lS1pWa7NroBC/zYcEQxa9gQho= X-Received: by 2002:ac8:4c8d:: with SMTP id j13mr32009866qtv.142.1588146140928; Wed, 29 Apr 2020 00:42:20 -0700 (PDT) MIME-Version: 1.0 References: <20200427200626.1622060-2-hch@lst.de> <20200428120207.15728-1-jk@ozlabs.org> <20200428171133.GA17445@lst.de> <20200429061514.GD30946@lst.de> <2014678ca837f6aaa4cf23b4ea51e4805146c36d.camel@ozlabs.org> In-Reply-To: <2014678ca837f6aaa4cf23b4ea51e4805146c36d.camel@ozlabs.org> From: Arnd Bergmann Date: Wed, 29 Apr 2020 09:42:04 +0200 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [RFC PATCH] powerpc/spufs: fix copy_to_user while atomic To: Jeremy Kerr Cc: Christoph Hellwig , Linus Torvalds , "Eric W . Biederman" , Andrew Morton , Alexander Viro , Michael Ellerman , linuxppc-dev , Linux FS-devel Mailing List , "linux-kernel@vger.kernel.org" Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:0F+MXJdpbdc8prDZpJ1o0fXcWKpXA6GHBMcS6NM7GMZHddCJt3d lSJ13n+AikE9nKXFORVKe4Qs0Jh+HErHj5vnWBO5TNyhOf60oSgbiK+ra4/t09GZ2ddMWaV C5oz1NxXyh/7ozpWKqx9XlmyTYkp/856b70jnOFs1QRSI7UGbYzzaJ612bwdGEvgrsOVFME F3lF04orawvvqY6a+6Ihw== X-UI-Out-Filterresults: notjunk:1;V03:K0:0lGVva0neKE=:8/YCBhn/FU+mNBnNGbE08T OodQyvsqEpg/TpLsQauCtU7AfaV2xkMHDzG241UV9cxGPDV6V/7+L7RXzRhUMWL+VMpJLXXLP hDsTpoymddUSb0x3jbsDJQDtO4aJ4fVX3VoRZQOrdLhcNf7D1XbqJlsmnX46pmUt2elXerNTj bo2Cqgc2yxjBzdFjKTgvrK7D3ik/bayNYiPV8jy/+q/ZDb4i5eK6VRuWRy6D1Q9VMlAQ4KKQW rM2skiyjNg26/+ebCJUDaIaWtoURJE8rpJiHVmBDUiW406B0ufXXzhUKQT/Hj8fh/8spSY9Qs 9GaRR6IqmSSQvBJBa7tt/LgC7zDrOfswUgtOhqINmvyIAMBJfSQoMxAJeUOpqg9pOk0dmue7G oh+CUX+H/DPSXezN5P80PDjII94v6ylyUaKWv6Q27iloLV6OXbemGpiHGwNwKsT2ZTL7bQ29J L1FL8jYEtu7QsaDu2tYYn3LvyGsgoaBTERLrTK97E0Ipj0hwJFVwk5i/vrq8fSjoV1YazLGTb WDL2QCAxWhrVLujC0Eo/UdKXhRgHMiaMzKFFzaJQ6kzAa9B2uIc5JS/KDoJjoeoLHwW9kZ5EB alaZ155sRgdBp2cUv+6VJmMdOVW+BrKJDqrJlU6cnzilgNv43OBJDdxecYkg9n1KQp3yxLepo 5RkXKXEX94NGeT3kYHuJKjJ2ULG4U1C4EquOp55vAMTCKDhJNDXTYL73t1caOreK6mM7VU5OT kwdwmwvuK0/zjI/yzSTCccCF7sHRvtu/nfjwouqr8JDj0Cw6WfbVOVxXXvw1JelzbK9jw+aTc 22MrAs4CbMG3smYXxlE/9WIdlJPBBn/QHteMAxFOolE/AQhB/0= Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 29, 2020 at 8:33 AM Jeremy Kerr wrote: > > Hi Christoph, > > > And another one that should go on top of this one to address Al's other > > compaint: > > Yeah, I was pondering that one. The access_ok() is kinda redundant, but > it does avoid forcing a SPU context save on those errors. > > However, it's not like we really need to optimise for the case of > invalid addresses from userspace. So, I'll include this change in the > submission to Michael's tree. Arnd - let me know if you have any > objections. Sounds good. A lot of the access_ok() checks in the kernel are redundant or wrong, I think it makes a lot of sense to remove these. Arnd