Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1949825AbdDYQ7J (ORCPT ); Tue, 25 Apr 2017 12:59:09 -0400 Received: from ale.deltatee.com ([207.54.116.67]:49357 "EHLO ale.deltatee.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1432405AbdDYQ7A (ORCPT ); Tue, 25 Apr 2017 12:59:00 -0400 To: Marta Rybczynska References: <1490911959-5146-1-git-send-email-logang@deltatee.com> <63d73995-4dfa-6270-ca13-972e0628011b@deltatee.com> <117239810.400362790.1493121533234.JavaMail.zimbra@kalray.eu> Cc: Sinan Kaya , Christoph Hellwig , Sagi Grimberg , "James E.J. Bottomley" , "Martin K. Petersen" , Jens Axboe , Steve Wise , Stephen Bates , Max Gurtovoy , Dan Williams , Keith Busch , Jason Gunthorpe , linux-pci@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nvme@lists.infradead.org, linux-rdma@vger.kernel.org, linux-nvdimm@ml01.01.org, linux-kernel@vger.kernel.org, Alex Williamson , Bjorn Helgaas From: Logan Gunthorpe Message-ID: <190d9a89-e227-e410-5886-ee2e20a9b941@deltatee.com> Date: Tue, 25 Apr 2017 10:58:40 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <117239810.400362790.1493121533234.JavaMail.zimbra@kalray.eu> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-SA-Exim-Connect-IP: 172.16.1.111 X-SA-Exim-Rcpt-To: bhelgaas@google.com, alex.williamson@redhat.com, linux-kernel@vger.kernel.org, linux-nvdimm@lists.01.org, linux-rdma@vger.kernel.org, linux-nvme@lists.infradead.org, linux-scsi@vger.kernel.org, linux-pci@vger.kernel.org, jgunthorpe@obsidianresearch.com, keith.busch@intel.com, dan.j.williams@intel.com, maxg@mellanox.com, sbates@raithlin.com, swise@opengridcomputing.com, axboe@kernel.dk, martin.petersen@oracle.com, jejb@linux.vnet.ibm.com, sagi@grimberg.me, hch@lst.de, okaya@codeaurora.org, mrybczyn@kalray.eu X-SA-Exim-Mail-From: logang@deltatee.com Subject: Re: [RFC 1/8] Introduce Peer-to-Peer memory (p2pmem) device 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: 366 Lines: 11 On 25/04/17 05:58 AM, Marta Rybczynska wrote: > I would add one issue that doesn't seem to be addressed: in my experience > P2P doesn't work when IOMMU activated. It works best with deactivation at > the BIOS level, even the kernel options are not enough in some cases. Well this would likely be addressed by 'arch_p2p_cross_segment' as proposed by Jason. Logan