On Fri, Dec 13, 2024 at 09:10:30AM +0000, David Woodhouse wrote: > <fantasy> > A: The guest OS just hands the device a standard MSI message encoding > the target guest APIC ID and vector (etc.), and the IOMMU does the > rest. Nothing 'intercedes' between the guest and the device to mess > with that MSI message. > /me wakes up... Well, I share your dream at least. :\ Have the VMM shadow the virtual interrupt remapping tables and assign it to the phyiscal remapping so that the physical addr/data pair doesn't change. Driving interrupt routing fully via the remapping HW and not via MSI interception. IIRC Alex had a patch series for qemu to capture and rewrite the ath non-standard MSI locations, so virtualization worries should not block moving ath to use the device-specific MSI.. Jason
