1:1 mapping

1:1 mapping

[Marty Kurtz]

Hi all

I work in the embedded world and am evaluating potential hypervisors
and kvm looks suitable for what we want
However, I see some old references to 1:1 mapping which would allow a
guest to see a PCI device even without an IOMMU

Is this currently incorporated into the qemu-0.11 and kvm-88 release?

Is dma=none equivalent to this by any chance or is it only meant for
devices that do not use DMA?

If 1:1 mapping is not in the tree, is there a reasonable chance that
the old patch would work with the latest?

Thanks
Marty

Re: 1:1 mapping

[Avi Kivity]

On 11/17/2009 01:39 AM, Marty Kurtz wrote:
> Hi all
>
> I work in the embedded world and am evaluating potential hypervisors
> and kvm looks suitable for what we want
> However, I see some old references to 1:1 mapping which would allow a
> guest to see a PCI device even without an IOMMU
>
> Is this currently incorporated into the qemu-0.11 and kvm-88 release?
>
>    

No.

> Is dma=none equivalent to this by any chance or is it only meant for
> devices that do not use DMA?
>
> If 1:1 mapping is not in the tree, is there a reasonable chance that
> the old patch would work with the latest?
>    

The interest in 1:1 has waned as more hardware now has an iommu, and 
because 1:1 can only support one guest, and insecurely at that.  The 
patches may work, but are unlikely to make it upsteam now.

-- 
error compiling committee.c: too many arguments to function