From: Jason Gunthorpe <jgg@nvidia.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: kwankhede@nvidia.com, acurrid@nvidia.com, kevin.tian@intel.com,
yishaih@nvidia.com, cjia@nvidia.com, kvm@vger.kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
jhubbard@nvidia.com, dri-devel@lists.freedesktop.org,
apopple@nvidia.com, ankita@nvidia.com,
shameerali.kolothum.thodi@huawei.com,
linux-kernel@vger.kernel.org, vsethi@nvidia.com,
alex.williamson@redhat.com, targupta@nvidia.com,
aniketa@nvidia.com, David Airlie <airlied@redhat.com>,
danw@nvidia.com
Subject: Re: [PATCH v7 1/1] vfio/nvgpu: Add vfio pci variant module for grace hopper
Date: Wed, 30 Aug 2023 12:39:05 -0300 [thread overview]
Message-ID: <ZO9imcoN5l28GE9+@nvidia.com> (raw)
In-Reply-To: <ZO9JKKurjv4PsmXh@infradead.org>
On Wed, Aug 30, 2023 at 06:50:32AM -0700, Christoph Hellwig wrote:
> I know I'm chiming in a bit late, but what ultimate user space is going
> to use this? We should not add anything to the kernel that can't
> be used without fully open user space.
qemu will get the matching VFIO userspace patches, I think they were
posted someplace already.
> vfio has traditionally been a bit special as it "just" passes devices
> through, so any user space could just be a user space driver for a
> random device on $FOO bus, including an actual Linux driver in a VM,
> but this driver has very specific semantics for a very specific piece
> of hardware, so it really needs to be treated like a generic GPU driver
> or accelerator driver.
This is basically a pre-CXL driver. It takes a PCI device and some
non-standard CXL-ish metadata and adapts it to VFIO.
In a post-CXL world this same functionality of managing the 'cache
coherent BAR' for VFIO would be done generically by some generic
vfio-cxl driver.
Jason
WARNING: multiple messages have this Message-ID (diff)
From: Jason Gunthorpe <jgg@nvidia.com>
To: Christoph Hellwig <hch@infradead.org>
Cc: ankita@nvidia.com, alex.williamson@redhat.com,
yishaih@nvidia.com, shameerali.kolothum.thodi@huawei.com,
kevin.tian@intel.com, aniketa@nvidia.com, cjia@nvidia.com,
kwankhede@nvidia.com, targupta@nvidia.com, vsethi@nvidia.com,
acurrid@nvidia.com, apopple@nvidia.com, jhubbard@nvidia.com,
danw@nvidia.com, kvm@vger.kernel.org,
linux-kernel@vger.kernel.org,
Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
David Airlie <airlied@redhat.com>,
dri-devel@lists.freedesktop.org, Daniel Vetter <daniel@ffwll.ch>
Subject: Re: [PATCH v7 1/1] vfio/nvgpu: Add vfio pci variant module for grace hopper
Date: Wed, 30 Aug 2023 12:39:05 -0300 [thread overview]
Message-ID: <ZO9imcoN5l28GE9+@nvidia.com> (raw)
In-Reply-To: <ZO9JKKurjv4PsmXh@infradead.org>
On Wed, Aug 30, 2023 at 06:50:32AM -0700, Christoph Hellwig wrote:
> I know I'm chiming in a bit late, but what ultimate user space is going
> to use this? We should not add anything to the kernel that can't
> be used without fully open user space.
qemu will get the matching VFIO userspace patches, I think they were
posted someplace already.
> vfio has traditionally been a bit special as it "just" passes devices
> through, so any user space could just be a user space driver for a
> random device on $FOO bus, including an actual Linux driver in a VM,
> but this driver has very specific semantics for a very specific piece
> of hardware, so it really needs to be treated like a generic GPU driver
> or accelerator driver.
This is basically a pre-CXL driver. It takes a PCI device and some
non-standard CXL-ish metadata and adapts it to VFIO.
In a post-CXL world this same functionality of managing the 'cache
coherent BAR' for VFIO would be done generically by some generic
vfio-cxl driver.
Jason
next prev parent reply other threads:[~2023-08-30 15:39 UTC|newest]
Thread overview: 23+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-08-22 20:23 [PATCH v7 1/1] vfio/nvgpu: Add vfio pci variant module for grace hopper ankita
2023-08-22 22:29 ` Alex Williamson
2023-08-23 13:56 ` Jason Gunthorpe
2023-08-23 14:18 ` Ankit Agrawal
2023-08-23 14:25 ` Jason Gunthorpe
2023-08-23 14:26 ` Alex Williamson
2023-08-23 14:50 ` Ankit Agrawal
2023-08-23 15:14 ` Alex Williamson
2023-08-23 15:16 ` Jason Gunthorpe
2023-08-23 15:24 ` Alex Williamson
2023-08-30 13:50 ` Christoph Hellwig
2023-08-30 15:39 ` Jason Gunthorpe [this message]
2023-08-30 15:39 ` Jason Gunthorpe
2023-08-31 12:26 ` Christoph Hellwig
2023-08-31 13:51 ` Ankit Agrawal
2023-08-31 13:51 ` Ankit Agrawal
2023-08-31 14:04 ` Christoph Hellwig
2023-08-31 18:21 ` Alex Williamson
2023-08-31 18:21 ` Alex Williamson
2023-09-01 0:44 ` Jason Gunthorpe
2023-09-01 0:44 ` Jason Gunthorpe
2023-09-01 5:48 ` Christoph Hellwig
2023-09-01 5:47 ` 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=ZO9imcoN5l28GE9+@nvidia.com \
--to=jgg@nvidia.com \
--cc=acurrid@nvidia.com \
--cc=airlied@redhat.com \
--cc=alex.williamson@redhat.com \
--cc=aniketa@nvidia.com \
--cc=ankita@nvidia.com \
--cc=apopple@nvidia.com \
--cc=cjia@nvidia.com \
--cc=danw@nvidia.com \
--cc=dri-devel@lists.freedesktop.org \
--cc=gregkh@linuxfoundation.org \
--cc=hch@infradead.org \
--cc=jhubbard@nvidia.com \
--cc=kevin.tian@intel.com \
--cc=kvm@vger.kernel.org \
--cc=kwankhede@nvidia.com \
--cc=linux-kernel@vger.kernel.org \
--cc=shameerali.kolothum.thodi@huawei.com \
--cc=targupta@nvidia.com \
--cc=vsethi@nvidia.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.