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=-7.2 required=3.0 tests=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 B2C16C3A59C for ; Fri, 16 Aug 2019 15:41:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 857B7206C2 for ; Fri, 16 Aug 2019 15:41:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727385AbfHPPlL (ORCPT ); Fri, 16 Aug 2019 11:41:11 -0400 Received: from mx2.suse.de ([195.135.220.15]:58810 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727376AbfHPPlK (ORCPT ); Fri, 16 Aug 2019 11:41:10 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 5584DAD0F; Fri, 16 Aug 2019 15:41:09 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id B6F151E4009; Fri, 16 Aug 2019 17:41:08 +0200 (CEST) Date: Fri, 16 Aug 2019 17:41:08 +0200 From: Jan Kara To: John Hubbard Cc: Ira Weiny , Jan Kara , Andrew Morton , Christoph Hellwig , Dan Williams , Dave Chinner , Jason Gunthorpe , =?iso-8859-1?B?Suly9G1l?= Glisse , LKML , linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-rdma@vger.kernel.org Subject: Re: [RFC PATCH 2/2] mm/gup: introduce vaddr_pin_pages_remote() Message-ID: <20190816154108.GE3041@quack2.suse.cz> References: <90e5cd11-fb34-6913-351b-a5cc6e24d85d@nvidia.com> <20190814234959.GA463@iweiny-DESK2.sc.intel.com> <2cbdf599-2226-99ae-b4d5-8909a0a1eadf@nvidia.com> <20190815132622.GG14313@quack2.suse.cz> <20190815133510.GA21302@quack2.suse.cz> <20190815173237.GA30924@iweiny-DESK2.sc.intel.com> <58b75fa9-1272-b683-cb9f-722cc316bf8f@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <58b75fa9-1272-b683-cb9f-722cc316bf8f@nvidia.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Thu 15-08-19 19:14:08, John Hubbard wrote: > On 8/15/19 10:41 AM, John Hubbard wrote: > > On 8/15/19 10:32 AM, Ira Weiny wrote: > >> On Thu, Aug 15, 2019 at 03:35:10PM +0200, Jan Kara wrote: > >>> On Thu 15-08-19 15:26:22, Jan Kara wrote: > >>>> On Wed 14-08-19 20:01:07, John Hubbard wrote: > >>>>> On 8/14/19 5:02 PM, John Hubbard wrote: > ... > >> Ok just to make this clear I threw up my current tree with your patches here: > >> > >> https://github.com/weiny2/linux-kernel/commits/mmotm-rdmafsdax-b0-v4 > >> > >> I'm talking about dropping the final patch: > >> 05fd2d3afa6b rdma/umem_odp: Use vaddr_pin_pages_remote() in ODP > >> > >> The other 2 can stay. I split out the *_remote() call. We don't have a user > >> but I'll keep it around for a bit. > >> > >> This tree is still WIP as I work through all the comments. So I've not changed > >> names or variable types etc... Just wanted to settle this. > >> > > > > Right. And now that ODP is not a user, I'll take a quick look through my other > > call site conversions and see if I can find an easy one, to include here as > > the first user of vaddr_pin_pages_remote(). I'll send it your way if that > > works out. > > > > OK, there was only process_vm_access.c, plus (sort of) Bharath's sgi-gru > patch, maybe eventually [1]. But looking at process_vm_access.c, I think > it is one of the patches that is no longer applicable, and I can just > drop it entirely...I'd welcome a second opinion on that... I don't think you can drop the patch. process_vm_rw_pages() clearly touches page contents and does not synchronize with page_mkclean(). So it is case 1) and needs FOLL_PIN semantics. Honza -- Jan Kara SUSE Labs, CR