Re: [Qemu-devel] [big lock] Discussion about the convention of device's DMA each other after breaking down biglock

[Paolo Bonzini]

Il 27/09/2012 11:16, Avi Kivity ha scritto:
> needs to be a little more complicated.  After translation, we need to
> look up the address again in a different phys_map.  So a MemoryRegion
> that is an iommu needs to hold its own phys_map pointer for the lookup.
> 
> But let's ignore the problem for now, we have too much on our plate.
> With a recursive big lock, there is no problem with iommus, yes?  So as
> long as there is no intersection between converted devices and platforms
> with iommus, we're safe.

pSeries has both PCI and iommu, but I think no one should be using e1000
on a pSeries.  virtio-net is per-spec not going through the iommu.

Paolo