On 19/09/2017 16:12, Alexey Kardashevskiy wrote: >>> What is the exact concern about the "[PATCH qemu v3 01/13] memory: Postpone >>> flatview and dispatch tree building till all devices are added"? Is it that >>> you missed that modern AS thing in virtio and thought we can do well even >>> without it? >> I am afraid that some of the special sysbus devices (not PCI, those go >> through the bus master DMA region and it's empty on startup) might write >> to memory during initialization. > > And somehow QEMU guarantees that all RAM MRs are rendered to FlatViews even > though some might be added via -device (can they btw?)?
I don't know, but as discussed on IRC, I think this is a pretty different change from the rest of the series---which should have zero change except for going faster---so I'd prefer to keep it out for now and see where optimization can get us. Paolo
