linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Christoph Hellwig <hch@lst.de>, Lei Rao <lei.rao@intel.com>,
	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 1/5] nvme-pci: add function nvme_submit_vf_cmd to issue admin commands for VF driver.
Date: Tue, 6 Dec 2022 17:55:03 +0100	[thread overview]
Message-ID: <20221206165503.GA8677@lst.de> (raw)
In-Reply-To: <Y49k++D3i8DfLOLL@ziepe.ca>

On Tue, Dec 06, 2022 at 11:51:23AM -0400, Jason Gunthorpe wrote:
> That is a big deviation from where VFIO is right now, the controlled
> function is the one with the VFIO driver, it should be the one that
> drives the migration uAPI components.

Well, that is one way to see it, but I think the more natural
way to deal with it is to drive everyting from the controlling
function, because that is by definition much more in control.

More importantly any sane design will have easy ways to list and
manipulate all the controlled functions from the controlling
functions, while getting from the controlled function to the
controlling one is extremely awkward, as anything that can be
used for that is by definition and information leak.  It seems
mlx5 just gets away with that by saying controlled functions are
always VFs, and the controlling function is a PF, but that will
break down very easily, especially once you want to nest the
controlling scheme (and yes, I'm not making this up, as the
nesting scheme is being proposed for nvme privately).

  reply	other threads:[~2022-12-06 16:55 UTC|newest]

Thread overview: 65+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-06  5:58 [RFC PATCH 0/5] Add new VFIO PCI driver for NVMe devices Lei Rao
2022-12-06  5:58 ` [RFC PATCH 1/5] nvme-pci: add function nvme_submit_vf_cmd to issue admin commands for VF driver Lei Rao
2022-12-06  6:19   ` Christoph Hellwig
2022-12-06 13:44     ` Jason Gunthorpe
2022-12-06 13:51       ` Keith Busch
2022-12-06 14:27         ` Jason Gunthorpe
2022-12-06 13:58       ` Christoph Hellwig
2022-12-06 15:22         ` Jason Gunthorpe
2022-12-06 15:38           ` Christoph Hellwig
2022-12-06 15:51             ` Jason Gunthorpe
2022-12-06 16:55               ` Christoph Hellwig [this message]
2022-12-06 19:15                 ` Jason Gunthorpe
2022-12-07  2:30                   ` Max Gurtovoy
2022-12-07  7:58                     ` Christoph Hellwig
2022-12-09  2:11                       ` Tian, Kevin
2022-12-12  7:41                         ` Christoph Hellwig
2022-12-07  7:54                   ` Christoph Hellwig
2022-12-07 10:59                     ` Max Gurtovoy
2022-12-07 13:46                       ` Christoph Hellwig
2022-12-07 14:50                         ` Max Gurtovoy
2022-12-07 16:35                           ` Christoph Hellwig
2022-12-07 13:34                     ` Jason Gunthorpe
2022-12-07 13:52                       ` Christoph Hellwig
2022-12-07 15:07                         ` Jason Gunthorpe
2022-12-07 16:38                           ` Christoph Hellwig
2022-12-07 17:31                             ` Jason Gunthorpe
2022-12-07 18:33                               ` Christoph Hellwig
2022-12-07 20:08                                 ` Jason Gunthorpe
2022-12-09  2:50                                   ` Tian, Kevin
2022-12-09 18:56                                     ` Dong, Eddie
2022-12-11 11:39                                   ` Max Gurtovoy
2022-12-12  7:55                                     ` Christoph Hellwig
2022-12-12 14:49                                       ` Max Gurtovoy
2022-12-12  7:50                                   ` Christoph Hellwig
2022-12-13 14:01                                     ` Jason Gunthorpe
2022-12-13 16:08                                       ` Christoph Hellwig
2022-12-13 17:49                                         ` Jason Gunthorpe
2022-12-06  5:58 ` [RFC PATCH 2/5] nvme-vfio: add new vfio-pci driver for NVMe device Lei Rao
2022-12-06  5:58 ` [RFC PATCH 3/5] nvme-vfio: enable the function of VFIO live migration Lei Rao
2023-01-19 10:21   ` Max Gurtovoy
2023-02-09  9:09     ` Rao, Lei
2022-12-06  5:58 ` [RFC PATCH 4/5] nvme-vfio: check if the hardware supports " Lei Rao
2022-12-06 13:47   ` Keith Busch
2022-12-06  5:58 ` [RFC PATCH 5/5] nvme-vfio: Add a document for the NVMe device Lei Rao
2022-12-06  6:26   ` Christoph Hellwig
2022-12-06 13:05     ` Jason Gunthorpe
2022-12-06 13:09       ` Christoph Hellwig
2022-12-06 13:52         ` Jason Gunthorpe
2022-12-06 14:00           ` Christoph Hellwig
2022-12-06 14:20             ` Jason Gunthorpe
2022-12-06 14:31               ` Christoph Hellwig
2022-12-06 14:48                 ` Jason Gunthorpe
2022-12-06 15:01                   ` Christoph Hellwig
2022-12-06 15:28                     ` Jason Gunthorpe
2022-12-06 15:35                       ` Christoph Hellwig
2022-12-06 18:00                         ` Dong, Eddie
2022-12-12  7:57                           ` Christoph Hellwig
2022-12-11 12:05                     ` Max Gurtovoy
2022-12-11 13:21                       ` Rao, Lei
2022-12-11 14:51                         ` Max Gurtovoy
2022-12-12  1:20                           ` Rao, Lei
2022-12-12  8:09                           ` Christoph Hellwig
2022-12-09  2:05         ` Tian, Kevin
2022-12-09 16:53           ` Li, Yadong
2022-12-12  8:11             ` Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20221206165503.GA8677@lst.de \
    --to=hch@lst.de \
    --cc=Konrad.wilk@oracle.com \
    --cc=alex.williamson@redhat.com \
    --cc=axboe@fb.com \
    --cc=cohuck@redhat.com \
    --cc=eddie.dong@intel.com \
    --cc=hang.yuan@intel.com \
    --cc=jgg@ziepe.ca \
    --cc=kbusch@kernel.org \
    --cc=kch@nvidia.com \
    --cc=kevin.tian@intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=lei.rao@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nvme@lists.infradead.org \
    --cc=mjrosato@linux.ibm.com \
    --cc=sagi@grimberg.me \
    --cc=shameerali.kolothum.thodi@huawei.com \
    --cc=stephen@eideticom.com \
    --cc=yadong.li@intel.com \
    --cc=yi.l.liu@intel.com \
    --cc=yishaih@nvidia.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).