On 08/01/2011 11:27 PM, Alex Williamson wrote:
On Sun, 2011-07-31 at 17:09 +0300, Avi Kivity wrote: > On 07/30/2011 02:58 AM, Benjamin Herrenschmidt wrote: > > Due to our paravirt nature, we don't need to masquerade the MSI-X table > > for example. At all. If the guest configures crap into it, too bad, it > > can only shoot itself in the foot since the host bridge enforce > > validation anyways as I explained earlier. Because it's all paravirt, we > > don't need to "translate" the interrupt vectors& addresses, the guest > > will call hyercalls to configure things anyways. > > So, you have interrupt redirection? That is, MSI-x table values encode > the vcpu, not pcpu? > > Alex, with interrupt redirection, we can skip this as well? Perhaps > only if the guest enables interrupt redirection? It's not clear to me how we could skip it. With VT-d, we'd have to implement an emulated interrupt remapper and hope that the guest picks unused indexes in the host interrupt remapping table before it could do anything useful with direct access to the MSI-X table.
Yeah. We need the interrupt remapping hardware to indirect based on the source of the message, not just the address and data.
Maybe AMD IOMMU makes this easier? Thanks,
No idea. -- error compiling committee.c: too many arguments to function -- 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
