On Wed, Apr 27, 2016 at 04:15:35PM +0100, David Woodhouse wrote: > On Wed, 2016-04-27 at 18:05 +0300, Michael S. Tsirkin wrote: > > > > I really don't get it. > > > > There's exactly one device that works now and needs the work-around and > > so that we need to support, and that is virtio. It happens to have > > exactly the same issue on all platforms. > > False. We have other devices which are currently *not* translated by > the emulated IOMMU and which aren't going to be in the short term > either. > > We also have other devices (emulated hardware NICs) to which precisely > the same "we don't need protection" arguments apply, and which we > *could* expose to the guest without an IOMMU translation if we really > wanted to. It makes as much sense as exposing virtio without an IOMMU, > going forward. The reasons for virtio are mostly dealing legacy. We don't need protection is a separate issue that I'd rather drop for now. > > Why would we want to work hard to build platform-specific > > solutions to a problem that can be solved in 5 lines of > > generic code? > > Because it's a dirty hack in the *wrong* place. No one came up with a better one so far :( > -- > dwmw2 -- 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
