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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_PASS 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 441F7C43381 for ; Wed, 20 Mar 2019 14:55:40 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id EFBC12146E for ; Wed, 20 Mar 2019 14:55:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="FE175wIn" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EFBC12146E Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=oracle.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id A405A6B0006; Wed, 20 Mar 2019 10:55:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9EF336B0007; Wed, 20 Mar 2019 10:55:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 904E56B0008; Wed, 20 Mar 2019 10:55:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from mail-yw1-f69.google.com (mail-yw1-f69.google.com [209.85.161.69]) by kanga.kvack.org (Postfix) with ESMTP id 6C5BE6B0006 for ; Wed, 20 Mar 2019 10:55:39 -0400 (EDT) Received: by mail-yw1-f69.google.com with SMTP id p1so3432257ywm.6 for ; Wed, 20 Mar 2019 07:55:39 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:dkim-signature:mime-version:subject:from :in-reply-to:date:cc:content-transfer-encoding:message-id:references :to; bh=vyTalyJPAp/99xZSU46vuHhBhzH/5qMxRbhLufZJza8=; b=WpripNtxe+9xYbYcz2y0sNhUgd3hWwB67Dzt2IQAVCC1Lh3nByU9/QiT3PTgMDlDN7 Fyiv5OTXUgmgq7xFx4FpFUIUD3qcTOUJiFgS/M9BAXSzEur+DiejFbMWthBvuAkVtN2w +5nUAzjv4HyD8Lzv7tkyLQNQmV8eAgdOQPAqzw1zyDRA91pGl57oWJdRtOXmkG59+4EF UmkwF8pd6WmW5Eub8hc9wm8h4gQaCfncv7LT2oMIPxz1Pq9lt8Pv7FtP8YYwAdXzkDew Ji8/tHd4jpg5uvBNAmQb1vuKamf++O6EbdgiHwqhPVsKKiS+lxWz9DTdWIdU9myXeH+W dADA== X-Gm-Message-State: APjAAAXAkH7yw77+4pSJiWXUuZP0oZrcjpf8UN/em4Aq7cuadUi0DSFY azd3RPxKPLL7lpCZsHzNImLqZa3pXjiKpPWprmL+yfFnRM1y2jki/cQiXv/ZyOSJoz0YWJtI/nx smAiCt8tjOk0Cbk0bU9wSejXizLbUIC9kARxvD8yvRKrzaR0dcjlgsMe+XJMygCMDng== X-Received: by 2002:a25:5782:: with SMTP id l124mr7473680ybb.114.1553093739208; Wed, 20 Mar 2019 07:55:39 -0700 (PDT) X-Google-Smtp-Source: APXvYqyZUVbJy71pEbJSFBMpsku/D8awdc3CurIqeK671YN68ziDIxAkYdC2+gTxeiOuVnFGzjIm X-Received: by 2002:a25:5782:: with SMTP id l124mr7473639ybb.114.1553093738596; Wed, 20 Mar 2019 07:55:38 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1553093738; cv=none; d=google.com; s=arc-20160816; b=oTHklRfhol5lRJc3Hwa/wfWXwIbzs0j6TUcvb2XYhGy7M74ziUJTS4m9b7Vfk9a/PD mxcJuvAymiSSgPOuZZd7aix9pLMnAC8cpaTENHwQ2kpsYmqxpMvupPXackLbftoTYT5g G4fWB4pkszRihj6pux0omb+EWegRCg/5fsYJaWqe3kBA7NAiHaJTTyNPZsVsGoatjAFn 3e1X5k70yH2hbR22A4btCiMQ7JYlyZWzVQbJa4Y+Z/+8cMK6w00HdSLXJI+0o4o0aL7k VCNKr2ZY9dGww7yOGGU+WZB5UJVijv3C5n30xRTQxJhQES7DNZ36NakGpCRLwsRqQ/7s uvMg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:dkim-signature; bh=vyTalyJPAp/99xZSU46vuHhBhzH/5qMxRbhLufZJza8=; b=pAAsK4xWhfEF00uJtIghel0PrhEQfl48WVbSUXEpFPvKzrsr6IlUXPfs6udmuo5lgI hbAm4zA8mJ00u0cy5HSQ/myMqOGP2kryUfRezK6thSwoXwImxCX7ZbBVRn/7E/lj7QX3 Phl/cmDiYLJNkw07Kp3CgEBaZN25pobvvwOU+1NsKOC5B0CSgSa43Lr9VxYykj1MUydZ j59TV9v8vq5OkSJu3qCCnYuscR89sJDNju6z88JAPMDufQ4mLQcTrTNdzxOONoWO0SYP HwP2H46NweTWAXw5nSWeqSr0YHVwoV0mZIa2phNphYqp8V/h4P0DPXcKsTn2AxMdvZB/ Qczg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2018-07-02 header.b=FE175wIn; spf=pass (google.com: domain of william.kucharski@oracle.com designates 156.151.31.86 as permitted sender) smtp.mailfrom=william.kucharski@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Received: from userp2130.oracle.com (userp2130.oracle.com. [156.151.31.86]) by mx.google.com with ESMTPS id v64si1348407ywb.297.2019.03.20.07.55.38 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 20 Mar 2019 07:55:38 -0700 (PDT) Received-SPF: pass (google.com: domain of william.kucharski@oracle.com designates 156.151.31.86 as permitted sender) client-ip=156.151.31.86; Authentication-Results: mx.google.com; dkim=pass header.i=@oracle.com header.s=corp-2018-07-02 header.b=FE175wIn; spf=pass (google.com: domain of william.kucharski@oracle.com designates 156.151.31.86 as permitted sender) smtp.mailfrom=william.kucharski@oracle.com; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=oracle.com Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.27/8.16.0.27) with SMTP id x2KEhaFt051492; Wed, 20 Mar 2019 14:55:24 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=content-type : mime-version : subject : from : in-reply-to : date : cc : content-transfer-encoding : message-id : references : to; s=corp-2018-07-02; bh=vyTalyJPAp/99xZSU46vuHhBhzH/5qMxRbhLufZJza8=; b=FE175wIndmjYqE9O1h9gs5/x/125rxIpTQyFuF9GQH3a6Qt22P3l4AlfYcZkplEIkwNy gL7VbxXqStMmQzDd7xdU1b0A57BVB8eoyezOVk6OCl1t5a1UMdVoKFq4Vw0/CxJ6C1ni hmF07JbaCWoErWy1V+EBBGOgYuvfftQ/Hclxb2Zh2YcX3qht8+vjjFLgvQpBSmpNyZeV FgHRKu1XeXc2w2qeNDJlMGA6OfsAYO+/xVIdbTPWmIgQ6xIjue2c/pJSTFqvDG7ArIP8 poCyhKg1J2b1Do1V6MWmoC7XL59Xaz+0GVdd/oY+2XtrqWGOcat534VBi/iLvPAvW5y6 dQ== Received: from userv0021.oracle.com (userv0021.oracle.com [156.151.31.71]) by userp2130.oracle.com with ESMTP id 2r8rjuubhn-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 20 Mar 2019 14:55:24 +0000 Received: from aserv0121.oracle.com (aserv0121.oracle.com [141.146.126.235]) by userv0021.oracle.com (8.14.4/8.14.4) with ESMTP id x2KEtMju002103 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 20 Mar 2019 14:55:23 GMT Received: from abhmp0022.oracle.com (abhmp0022.oracle.com [141.146.116.28]) by aserv0121.oracle.com (8.14.4/8.13.8) with ESMTP id x2KEtKfb010967; Wed, 20 Mar 2019 14:55:20 GMT Received: from [192.168.0.110] (/73.243.10.6) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 20 Mar 2019 07:55:20 -0700 Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.8\)) Subject: Re: [PATCH v4 1/1] mm: introduce put_user_page*(), placeholder versions From: William Kucharski In-Reply-To: <20190320043319.GA7431@redhat.com> Date: Wed, 20 Mar 2019 08:55:17 -0600 Cc: John Hubbard , Dave Chinner , "Kirill A. Shutemov" , john.hubbard@gmail.com, Andrew Morton , Linux MM , Al Viro , Christian Benvenuti , Christoph Hellwig , Christopher Lameter , Dan Williams , Dennis Dalessandro , Doug Ledford , Ira Weiny , Jan Kara , Jason Gunthorpe , Matthew Wilcox , Michal Hocko , Mike Rapoport , Mike Marciniszyn , Ralph Campbell , Tom Talpey , LKML , linux-fsdevel@vger.kernel.org, Andrea Arcangeli Content-Transfer-Encoding: 7bit Message-Id: References: <20190308213633.28978-1-jhubbard@nvidia.com> <20190308213633.28978-2-jhubbard@nvidia.com> <20190319120417.yzormwjhaeuu7jpp@kshutemo-mobl1> <20190319134724.GB3437@redhat.com> <20190319141416.GA3879@redhat.com> <20190319212346.GA26298@dastard> <20190319220654.GC3096@redhat.com> <20190319235752.GB26298@dastard> <20190320000838.GA6364@redhat.com> <20190320043319.GA7431@redhat.com> To: Jerome Glisse X-Mailer: Apple Mail (2.3445.104.8) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=9200 signatures=668685 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=913 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1903200113 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > On Mar 19, 2019, at 10:33 PM, Jerome Glisse wrote: > > So i believe best we could do is send a SIGBUS to the process that has > GUPed a range of a file that is being truncated this would match what > we do for CPU acces. There is no reason access through GUP should be > handled any differently. This should be done lazily, as there's no need to send the SIGBUS unless the GUPed page is actually accessed post-truncate.