> On Wed, Nov 25, 2015 at 12:21 AM, Lan Tianyu <tianyu....@intel.com> wrote: > > On 2015年11月25日 13:30, Alexander Duyck wrote: > >> No, what I am getting at is that you can't go around and modify the > >> configuration space for every possible device out there. This > >> solution won't scale. > > > > > > PCI config space regs are emulation by Qemu and so We can find the > > free PCI config space regs for the faked PCI capability. Its position > > can be not permanent. > > Yes, but do you really want to edit every driver on every OS that you plan to > support this on. What about things like direct assignment of regular Ethernet > ports? What you really need is a solution that will work generically on any > existing piece of hardware out there.
The fundamental assumption of this patch series is to modify the driver in guest to self-emulate or track the device state, so that the migration may be possible. I don't think we can modify OS, without modifying the drivers, even using the PCIe hotplug mechanism. In the meantime, modifying Windows OS is a big challenge given that only Microsoft can do. While, modifying driver is relatively simple and manageable to device vendors, if the device vendor want to support state-clone based migration. Thx Eddie