From: Jason Gunthorpe <jgg@nvidia.com>
To: "joro@8bytes.org" <joro@8bytes.org>
Cc: "Tian, Kevin" <kevin.tian@intel.com>,
Jason Wang <jasowang@redhat.com>,
"Liu, Yi L" <yi.l.liu@intel.com>,
"alex.williamson@redhat.com" <alex.williamson@redhat.com>,
"eric.auger@redhat.com" <eric.auger@redhat.com>,
"baolu.lu@linux.intel.com" <baolu.lu@linux.intel.com>,
"jacob.jun.pan@linux.intel.com" <jacob.jun.pan@linux.intel.com>,
"Raj, Ashok" <ashok.raj@intel.com>,
"Tian, Jun J" <jun.j.tian@intel.com>,
"Sun, Yi Y" <yi.y.sun@intel.com>,
"jean-philippe@linaro.org" <jean-philippe@linaro.org>,
"peterx@redhat.com" <peterx@redhat.com>,
"Wu, Hao" <hao.wu@intel.com>,
"stefanha@gmail.com" <stefanha@gmail.com>,
"iommu@lists.linux-foundation.org"
<iommu@lists.linux-foundation.org>,
"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
"Michael S. Tsirkin" <mst@redhat.com>
Subject: Re: (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs
Date: Tue, 3 Nov 2020 09:23:35 -0400 [thread overview]
Message-ID: <20201103132335.GO2620339@nvidia.com> (raw)
In-Reply-To: <20201103131852.GE22888@8bytes.org>
On Tue, Nov 03, 2020 at 02:18:52PM +0100, joro@8bytes.org wrote:
> On Tue, Nov 03, 2020 at 08:56:43AM -0400, Jason Gunthorpe wrote:
> > On Tue, Nov 03, 2020 at 10:52:09AM +0100, joro@8bytes.org wrote:
> > > So having said this, what is the benefit of exposing those SVA internals
> > > to user-space?
> >
> > Only the device use of the PASID is device specific, the actual PASID
> > and everything on the IOMMU side is generic.
> >
> > There is enough API there it doesn't make sense to duplicate it into
> > every single SVA driver.
>
> What generic things have to be done by the drivers besides
> allocating/deallocating PASIDs and binding an address space to it?
>
> Is there anything which isn't better handled in a kernel-internal
> library which drivers just use?
Userspace needs fine grained control over the composition of the page
table behind the PASID, 1:1 with the mm_struct is only one use case.
Userspace needs to be able to handle IOMMU faults, apparently
The Intel guys had a bunch of other stuff too, looking through the new
API they are proposing for vfio gives some flavour what they think is
needed..
Jason
next prev parent reply other threads:[~2020-11-03 13:23 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-12 8:38 (proposal) RE: [PATCH v7 00/16] vfio: expose virtual Shared Virtual Addressing to VMs Tian, Kevin
2020-10-13 6:22 ` Jason Wang
2020-10-14 3:08 ` Tian, Kevin
2020-10-14 23:10 ` Alex Williamson
2020-10-15 7:02 ` Jason Wang
2020-10-15 6:52 ` Jason Wang
2020-10-15 7:58 ` Tian, Kevin
2020-10-15 8:40 ` Jason Wang
2020-10-15 10:14 ` Liu, Yi L
2020-10-20 6:18 ` Jason Wang
2020-10-20 8:19 ` Liu, Yi L
2020-10-20 9:19 ` Jason Wang
2020-10-20 9:40 ` Liu, Yi L
2020-10-20 13:54 ` Jason Gunthorpe
2020-10-20 14:00 ` Liu, Yi L
2020-10-20 14:05 ` Jason Gunthorpe
2020-10-20 14:09 ` Liu, Yi L
2020-10-13 10:27 ` Jean-Philippe Brucker
2020-10-14 2:11 ` Tian, Kevin
2020-10-14 3:16 ` Tian, Kevin
2020-10-16 15:36 ` Jason Gunthorpe
2020-10-19 8:39 ` Liu, Yi L
2020-10-19 14:25 ` Jason Gunthorpe
2020-10-20 10:21 ` Liu, Yi L
2020-10-20 14:02 ` Jason Gunthorpe
2020-10-20 14:19 ` Liu, Yi L
2020-10-21 2:21 ` Jason Wang
2020-10-20 16:24 ` Raj, Ashok
2020-10-20 17:03 ` Jason Gunthorpe
2020-10-20 19:51 ` Raj, Ashok
2020-10-20 19:55 ` Jason Gunthorpe
2020-10-20 20:08 ` Raj, Ashok
2020-10-20 20:14 ` Jason Gunthorpe
2020-10-20 20:27 ` Raj, Ashok
2020-10-21 11:48 ` Jason Gunthorpe
2020-10-21 17:51 ` Raj, Ashok
2020-10-21 18:24 ` Jason Gunthorpe
2020-10-21 20:03 ` Raj, Ashok
2020-10-21 23:32 ` Jason Gunthorpe
2020-10-21 23:53 ` Raj, Ashok
2020-10-22 2:55 ` Jason Wang
2020-10-22 3:54 ` Liu, Yi L
2020-10-22 4:38 ` Jason Wang
2020-11-03 9:52 ` joro
2020-11-03 12:56 ` Jason Gunthorpe
2020-11-03 13:18 ` joro
2020-11-03 13:23 ` Jason Gunthorpe [this message]
2020-11-03 14:03 ` joro
2020-11-03 14:06 ` Jason Gunthorpe
2020-11-03 14:35 ` joro
2020-11-03 15:22 ` Jason Gunthorpe
2020-11-03 16:55 ` joro
2020-11-03 17:48 ` Jason Gunthorpe
2020-11-03 19:14 ` joro
2020-11-04 19:29 ` Jason Gunthorpe
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