[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vI
From: |
Michael S. Tsirkin |
Subject: |
Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present |
Date: |
Tue, 15 Mar 2016 09:00:17 +0200 |
On Mon, Mar 14, 2016 at 07:58:23PM +0100, Jan Kiszka wrote:
> On 2016-03-14 19:52, Marcel Apfelbaum wrote:
> > On 03/12/2016 06:13 PM, Aviv B.D. wrote:
> >> From: "Aviv B.D." <address@hidden <mailto:address@hidden>>
> >>
> >> * Fix bug that prevent qemu from starting up when vIOMMU and VFIO
> >> device are present.
> >> * Advertise Cache Mode capability in iommu cap register.
>
> For the final version: Please keep that feature optional, for the sake
> of emulation accuracy (no modern hw exposes it any more). Maybe turn it
> one once a vfio device is in the scope of the IOMMU?
That would be hard to implement: VFIO supports hotplug and there's no way to
change this on the fly.
I would say
- make the feature an optional flag
- deny adding a VFIO device if the flag is not set
> >> * Register every VFIO device with IOMMU state.
> >> * On page cache invalidation in vIOMMU, check if the domain belong to
> >> VFIO device and mirror the guest requests to host.
> >>
> >> Not working (Yet!):
> >> * Tested only with network interface card (ixgbevf) and
> >> intel_iommu=strict in guest's kernel command line.
> >> * Lock up under high load.
> >> * Errors on guest poweroff.
> >> * High relative latency compare to VFIO without IOMMU.
> >
> > Adding (possibly) interested developers to the thread.
>
> Thanks,
> Jan
>
> --
> Siemens AG, Corporate Technology, CT RDA ITP SES-DE
> Corporate Competence Center Embedded Linux
- [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Aviv B.D., 2016/03/12
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Marcel Apfelbaum, 2016/03/14
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Jan Kiszka, 2016/03/14
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present,
Michael S. Tsirkin <=
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Peter Xu, 2016/03/15
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Aviv B.D., 2016/03/17
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Peter Xu, 2016/03/17
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Aviv B.D., 2016/03/19
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Peter Xu, 2016/03/20
- Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Aviv B.D., 2016/03/22
Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Michael S. Tsirkin, 2016/03/15
Re: [Qemu-devel] [PATCH][RFC] IOMMU: Add Support to VFIO devices with vIOMMU present, Michael S. Tsirkin, 2016/03/23