Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752158AbcLET7q (ORCPT ); Mon, 5 Dec 2016 14:59:46 -0500 Received: from ale.deltatee.com ([207.54.116.67]:46010 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752037AbcLET7k (ORCPT ); Mon, 5 Dec 2016 14:59:40 -0500 To: Jason Gunthorpe References: <61a2fb07344aacd81111449d222de66e.squirrel@webmail.raithlin.com> <20161205171830.GB27784@obsidianresearch.com> <20161205180231.GA28133@obsidianresearch.com> <20161205191438.GA20464@obsidianresearch.com> <10356964-c454-47fb-7fb3-8bf2a418b11b@deltatee.com> <20161205194614.GA21132@obsidianresearch.com> Cc: Dan Williams , Stephen Bates , Haggai Eran , "linux-kernel@vger.kernel.org" , "linux-rdma@vger.kernel.org" , "linux-nvdimm@ml01.01.org" , "christian.koenig@amd.com" , "Suravee.Suthikulpanit@amd.com" , "John.Bridgman@amd.com" , "Alexander.Deucher@amd.com" , "Linux-media@vger.kernel.org" , "dri-devel@lists.freedesktop.org" , Max Gurtovoy , "linux-pci@vger.kernel.org" , "serguei.sagalovitch@amd.com" , "Paul.Blinzer@amd.com" , "Felix.Kuehling@amd.com" , "ben.sander@amd.com" From: Logan Gunthorpe Message-ID: Date: Mon, 5 Dec 2016 12:59:29 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Icedove/45.4.0 MIME-Version: 1.0 In-Reply-To: <20161205194614.GA21132@obsidianresearch.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 50.66.97.235 X-SA-Exim-Rcpt-To: ben.sander@amd.com, felix.kuehling@amd.com, paul.blinzer@amd.com, serguei.sagalovitch@amd.com, linux-pci@vger.kernel.org, maxg@mellanox.com, dri-devel@lists.freedesktop.org, linux-media@vger.kernel.org, alexander.deucher@amd.com, john.bridgman@amd.com, suravee.suthikulpanit@amd.com, christian.koenig@amd.com, linux-nvdimm@ml01.01.org, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, haggaie@mellanox.com, sbates@raithlin.com, dan.j.williams@intel.com, jgunthorpe@obsidianresearch.com X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: Enabling peer to peer device transactions for PCIe devices X-SA-Exim-Version: 4.2.1 (built Mon, 26 Dec 2011 16:24:06 +0000) X-SA-Exim-Scanned: Yes (on ale.deltatee.com) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 740 Lines: 19 On 05/12/16 12:46 PM, Jason Gunthorpe wrote: > NVMe might have to deal with pci-e hot-unplug, which is a similar > problem-class to the GPU case.. Sure, but if the NVMe device gets hot-unplugged it means that all the CMB mappings are useless and need to be torn down. This probably means killing any process that has mappings open. > In any event the allocator still needs to track which regions are in > use and be able to hook 'free' from userspace. That does suggest it > should be integrated into the nvme driver and not a bolt on driver.. Yup, that's correct. And yes, I've never suggested this to be a bolt on driver -- I always expected for it to get integrated into the nvme driver. (iopmem was not meant for this.) Logan