On Thu, 2010-06-17 at 23:01 +0100, Paul Brook wrote: > > > ### Paul proposes to require all buses to define bus addresses. Make > > > one up if necessary. > > > > That seems arbitrary and prone to breakage. How do we handle a subtle > > change in device instantiation order and still allow migration? If by > > code change or command line ordering my frobnitz moves from: > > > > /i440FX-pcihost/pci.0/PIIX3/@01.0/isa.0/0 > > > > to > > > > /i440FX-pcihost/pci.0/PIIX3/@01.0/isa.0/1 > > Two things are apparent here. > (a) You've clearly misunderstood the proposals. The paths above make no sense.
Sorry, hastily created paths. Though yes, I am a little unclear of the proposal, feel free to code up how it should work. I hope the other follow-up I just sent is more correct. > (b) You've picked a particularly poor definition of device address for the > ISA > bus. We can do much better than device creation order. Ok, how? > > ... > > I can live with PATH/@BUS-ADDR if it's still felt that > > PATH/id...@bus-addr isn't canonical. What that means is that I'll > > probably code up vmstate and ramblocks to append IDENT themselves to > > keep all the goodness of having per PATH/IDENT namespaces. > > As discussed elsewhere in this thread, addition of IDENT to the device path > is > neither necessary nor sufficient for migration. > > I really feel like we're going round in circles here. Um, I believe I just agreed to remove IDENT from the canonical path and append it in a usage specific way. I think I've cited a couple relevant examples of how this can improve the robustness of migration and I have yet to hear anything but conjecture that this is only a false sense of security. Alex
