From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <SRS0=K8VO=Y4=vger.kernel.org=linux-fsdevel-owner@kernel.org>
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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED,
	DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,
	SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 69BD2CA9ECF
	for <linux-fsdevel@archiver.kernel.org>; Mon,  4 Nov 2019 20:40:57 +0000 (UTC)
Received: from vger.kernel.org (vger.kernel.org [209.132.180.67])
	by mail.kernel.org (Postfix) with ESMTP id 407002089C
	for <linux-fsdevel@archiver.kernel.org>; Mon,  4 Nov 2019 20:40:57 +0000 (UTC)
Authentication-Results: mail.kernel.org;
	dkim=pass (2048-bit key) header.d=nvidia.com header.i=@nvidia.com header.b="NHQ1Q0ia"
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1729530AbfKDUkv (ORCPT
        <rfc822;linux-fsdevel@archiver.kernel.org>);
        Mon, 4 Nov 2019 15:40:51 -0500
Received: from hqemgate16.nvidia.com ([216.228.121.65]:2725 "EHLO
        hqemgate16.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1728519AbfKDUku (ORCPT
        <rfc822;linux-fsdevel@vger.kernel.org>);
        Mon, 4 Nov 2019 15:40:50 -0500
Received: from hqpgpgate101.nvidia.com (Not Verified[216.228.121.13]) by hqemgate16.nvidia.com (using TLS: TLSv1.2, DES-CBC3-SHA)
        id <B5dc08cd80000>; Mon, 04 Nov 2019 12:40:56 -0800
Received: from hqmail.nvidia.com ([172.20.161.6])
  by hqpgpgate101.nvidia.com (PGP Universal service);
  Mon, 04 Nov 2019 12:40:49 -0800
X-PGP-Universal: processed;
        by hqpgpgate101.nvidia.com on Mon, 04 Nov 2019 12:40:49 -0800
Received: from [10.110.48.28] (10.124.1.5) by HQMAIL107.nvidia.com
 (172.20.187.13) with Microsoft SMTP Server (TLS) id 15.0.1473.3; Mon, 4 Nov
 2019 20:40:48 +0000
Subject: Re: [PATCH v2 05/18] mm/gup: introduce pin_user_pages*() and FOLL_PIN
To:     Jason Gunthorpe <jgg@ziepe.ca>
CC:     Jerome Glisse <jglisse@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Alex Williamson <alex.williamson@redhat.com>,
        Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        =?UTF-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn.topel@intel.com>,
        Christoph Hellwig <hch@infradead.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Dave Chinner <david@fromorbit.com>,
        David Airlie <airlied@linux.ie>,
        "David S . Miller" <davem@davemloft.net>,
        Ira Weiny <ira.weiny@intel.com>, Jan Kara <jack@suse.cz>,
        Jens Axboe <axboe@kernel.dk>, Jonathan Corbet <corbet@lwn.net>,
        Magnus Karlsson <magnus.karlsson@intel.com>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Michal Hocko <mhocko@suse.com>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Paul Mackerras <paulus@samba.org>,
        Shuah Khan <shuah@kernel.org>,
        Vlastimil Babka <vbabka@suse.cz>, <bpf@vger.kernel.org>,
        <dri-devel@lists.freedesktop.org>, <kvm@vger.kernel.org>,
        <linux-block@vger.kernel.org>, <linux-doc@vger.kernel.org>,
        <linux-fsdevel@vger.kernel.org>, <linux-kselftest@vger.kernel.org>,
        <linux-media@vger.kernel.org>, <linux-rdma@vger.kernel.org>,
        <linuxppc-dev@lists.ozlabs.org>, <netdev@vger.kernel.org>,
        <linux-mm@kvack.org>, LKML <linux-kernel@vger.kernel.org>
References: <20191103211813.213227-1-jhubbard@nvidia.com>
 <20191103211813.213227-6-jhubbard@nvidia.com>
 <20191104173325.GD5134@redhat.com>
 <be9de35c-57e9-75c3-2e86-eae50904bbdf@nvidia.com>
 <20191104191811.GI5134@redhat.com>
 <e9656d47-b4a1-da8a-e8cc-ebcfb8cc06d6@nvidia.com>
 <20191104195248.GA7731@redhat.com>
 <25ec4bc0-caaa-2a01-2ae7-2d79663a40e1@nvidia.com>
 <20191104203117.GE30938@ziepe.ca>
From:   John Hubbard <jhubbard@nvidia.com>
X-Nvconfidentiality: public
Message-ID: <1c428985-6ede-ef75-62bd-26ccf99f6d38@nvidia.com>
Date:   Mon, 4 Nov 2019 12:40:48 -0800
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101
 Thunderbird/60.8.0
MIME-Version: 1.0
In-Reply-To: <20191104203117.GE30938@ziepe.ca>
X-Originating-IP: [10.124.1.5]
X-ClientProxiedBy: HQMAIL105.nvidia.com (172.20.187.12) To
 HQMAIL107.nvidia.com (172.20.187.13)
Content-Type: text/plain; charset="utf-8"
Content-Language: en-US
Content-Transfer-Encoding: 7bit
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nvidia.com; s=n1;
        t=1572900056; bh=DgUGakiDqU+H/jvLHI+F9dgZlEqXtDj8YZcQ5jdUUnc=;
        h=X-PGP-Universal:Subject:To:CC:References:From:X-Nvconfidentiality:
         Message-ID:Date:User-Agent:MIME-Version:In-Reply-To:
         X-Originating-IP:X-ClientProxiedBy:Content-Type:Content-Language:
         Content-Transfer-Encoding;
        b=NHQ1Q0iautz1x5eS1rpVt2XzAK+GdsKg4fHxuWzyx4M7tJpV+1UB6d5ZpY+LJM8ME
         TR31xYhwAxi1K+5UUf+wF2rdwAdcBiJd7g9PZ9zQdxs0smNT0eXx/EK23GNTVWWsim
         vmxoebMT8yRD8emjw4hl+mywMz6dGLzA9qU4y5rdocqaRh8e0dGYAC8/oxGzxQkYvT
         MWkQm/cvgwbgyxMEdYQt09KoKCaZDdAw2q8ktAtZsrow9mFYWcec570DR/POlaG1aB
         FjnA7v+FO5AVWFmkxPStSbC6bck0U4AV8Oy7tJVJh18dLUfTlW6x2kgIg6rLYkBdDJ
         g//zR0Vfe3smA==
Sender: linux-fsdevel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-fsdevel.vger.kernel.org>
X-Mailing-List: linux-fsdevel@vger.kernel.org

On 11/4/19 12:31 PM, Jason Gunthorpe wrote:
> On Mon, Nov 04, 2019 at 12:09:05PM -0800, John Hubbard wrote:
> 
>> Note for Jason: the (a) or (b) items are talking about the vfio case, which is
>> one of the two call sites that now use pin_longterm_pages_remote(), and the
>> other one is infiniband:
>>
>> drivers/infiniband/core/umem_odp.c:646:         npages = pin_longterm_pages_remote(owning_process, owning_mm,
> 
> This is a mistake, it is not a longterm pin and does not need FOLL_PIN
> semantics

OK! So it really just wants to be get_user_pages_remote() / put_page()? I'll
change it back to that.

> 
>> Jason should weigh in on how he wants this to go, with respect to branching
>> and merging, since it sounds like that will conflict with the hmm branch 
> 
> I think since you don't need to change this site things should be
> fine?
> 

Right. 


thanks,

John Hubbard
NVIDIA