[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add
From: |
Alex Williamson |
Subject: |
Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support] |
Date: |
Tue, 31 May 2016 08:29:26 -0600 |
On Tue, 31 May 2016 10:29:10 +0800
Jike Song <address@hidden> wrote:
> On 05/28/2016 10:56 PM, Alex Williamson wrote:
> > On Fri, 27 May 2016 22:43:54 +0000
> > "Tian, Kevin" <address@hidden> wrote:
> >
> >>
> >> My impression was that you don't like hypervisor specific thing in VFIO,
> >> which makes it a bit tricky to accomplish those tasks in kernel. If we
> >> can add Xen specific logic directly in VFIO (like vfio-iommu-xen you
> >> mentioned), the whole thing would be easier.
> >
> > If vfio is hosted in dom0, then Xen is the platform and we need to
> > interact with the hypervisor to manage the iommu. That said, there are
> > aspects of vfio that do not seem to map well to a hypervisor managed
> > iommu or a Xen-like hypervisor. For instance, how does dom0 manage
> > iommu groups and what's the distinction of using vfio to manage a
> > userspace driver in dom0 versus managing a device for another domain.
> > In the case of kvm, vfio has no dependency on kvm, there is some minor
> > interaction, but we're not running on kvm and it's not appropriate to
> > use vfio as a gateway to interact with a hypervisor that may or may not
> > exist. Thanks,
>
> Hi Alex,
>
> Beyond iommu, there are other aspects vfio need to interact with Xen?
> e.g. to pass-through MMIO, one have to call hypercalls to establish EPT
> mappings.
If it's part of running on a Xen platform and not trying to interact
with a VM in ways that are out of scope for vfio, I might be open to
it, I'd need to see a proposal. This also goes back to my question of
how does vfio know whether it's configuring a device for a guest driver
or a guest VM, with kvm these are one and the same. Thanks,
Alex
- Re: [Qemu-devel] [RFC PATCH v4 1/3] Mediated device Core driver, (continued)
[Qemu-devel] [RFC PATCH v4 3/3] VFIO Type1 IOMMU: Add support for mediated devices, Kirti Wankhede, 2016/05/24
Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support], Tian, Kevin, 2016/05/25
- Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support], Alex Williamson, 2016/05/25
- Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support], Tian, Kevin, 2016/05/27
- Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support], Alex Williamson, 2016/05/27
- Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support], Tian, Kevin, 2016/05/27
- Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support], Alex Williamson, 2016/05/28
- Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support], Jike Song, 2016/05/30
- Re: [Qemu-devel] [RFC PATCH v4 0/3] Add Mediated device support[was: Add vGPU support],
Alex Williamson <=