On Thu, Dec 24, 2009 at 02:56:00PM +0800, Sheng Yang wrote: > > > >And, of course, disabling the IOMMU requirement using the old: > > > > > > > > -pcidevice host=[addr],dma=none > > > > > > > >or the newer: > > > > > > > > -device pci-assign,host=[addr],iommu=0 > > > > > > > >will do what it always did (not require an IOMMU, and fail to work > > > >properly). > > > > > > Yay! > > > > Sounds good to me. Though I am curious to know the reasoning > > behind the current logic. > > > Sounds pretty good. :) > > I think maybe it due to we are interested in implementing PV DMA? Yes, we are. The current defaults came from the desire to support both pvdma and also 1-1 host mappings. There were patches floating around for both. Having said that, I fully agree with this change---the default should be to require IOMMU. Anything else is "highly experimental". Cheers, Muli -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
