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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 4D0ABC352A1 for ; Tue, 6 Dec 2022 14:01:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=vVONVhFIMozKQMIv6+ud8+0mfKas86XM8jPahKm21a4=; b=fpoZWTSGQalOgwGqb+0TzyjDJ6 gzlOMj1YtYu9VFIBs/WOdsjJ45icspWvOaKfWx5GonY6Ema/I8wE7lNHovLcnfTGcg7edrnINSffN rX5/eXyjcqTDmwwdCIM8KrC9mq9uRTzT7tdM9o4A0LWPi/9itcIYUKCVsvfJzzTCkM0VzO17Db41M NRiA4iZXeI8bhjHIOshZsBM/w63PaxlxWWnVKNePK7qE5DZRTlMYv1j/TV56AJGDyOe88jWdsRQfi w71P53PqzLYG6RGxM5H+QHVH/N1cKgWG59HqKprSuS+eognJi93wWu2ks60dqg3KQ2DBu0NUNDJX5 cxYcnapg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1p2YVR-00AA5f-5a; Tue, 06 Dec 2022 14:01:09 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1p2YUX-00A95u-AG for linux-nvme@lists.infradead.org; Tue, 06 Dec 2022 14:00:21 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 8B58B68B05; Tue, 6 Dec 2022 15:00:03 +0100 (CET) Date: Tue, 6 Dec 2022 15:00:02 +0100 From: Christoph Hellwig To: Jason Gunthorpe Cc: Christoph Hellwig , Lei Rao , kbusch@kernel.org, axboe@fb.com, kch@nvidia.com, sagi@grimberg.me, alex.williamson@redhat.com, cohuck@redhat.com, yishaih@nvidia.com, shameerali.kolothum.thodi@huawei.com, kevin.tian@intel.com, mjrosato@linux.ibm.com, linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, kvm@vger.kernel.org, eddie.dong@intel.com, yadong.li@intel.com, yi.l.liu@intel.com, Konrad.wilk@oracle.com, stephen@eideticom.com, hang.yuan@intel.com Subject: Re: [RFC PATCH 5/5] nvme-vfio: Add a document for the NVMe device Message-ID: <20221206140002.GB27689@lst.de> References: <20221206055816.292304-1-lei.rao@intel.com> <20221206055816.292304-6-lei.rao@intel.com> <20221206062604.GB6595@lst.de> <20221206130901.GB24358@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221206_060013_972789_048BB356 X-CRM114-Status: GOOD ( 19.41 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Dec 06, 2022 at 09:52:54AM -0400, Jason Gunthorpe wrote: > On Tue, Dec 06, 2022 at 02:09:01PM +0100, Christoph Hellwig wrote: > > On Tue, Dec 06, 2022 at 09:05:05AM -0400, Jason Gunthorpe wrote: > > > In this case Intel has a real PCI SRIOV VF to expose to the guest, > > > with a full VF RID. > > > > RID? > > "Requester ID" - PCI SIG term that in Linux basically means you get to > assign an iommu_domain to the vfio device. Yeah I now the Requester ID, I've just never seen that shortcut for it. > >From what I understood this series basically allows two Intel devices > to pass a big opaque blob of data. Intel didn't document what is in > that blob, so I assume it captures everything you mention above. Which would be just as bad, because it then changes the IDs under the live OS on a restore. This is not something that can be done behind the back of the hypervisors / control plane OS.