Mark McLoughlin wrote: > On Wed, 2009-06-10 at 20:27 +0100, Jamie Lokier wrote: > >> Michael S. Tsirkin wrote: >> >>>> I think the right long term answer to all this is a way to get QEMU to >>>> dump it's current machine configuration in glorious detail as a file >>>> which can be reloaded as a machine configuration. >>>> >>> And then we'll have the same set of problems there. >>> >> We will, and the solution will be the same: options to create devices >> as they were in older versions of QEMU. It only needs to cover device >> features which matter to guests, not every bug fix. >> >> However with a machine configuration which is generated by QEMU, >> there's less worry about proliferation of obscure options, compared >> with the command line. You don't necessarily have to document every >> backward-compatibility option in any detail, you just have to make >> sure it's written and read properly, which is much the same thing as >> the snapshot code does. >> > > This is a sensible plan, but I don't think we should mix these compat > options in with the VM manager supplied configuration. > > There are two problems with that approach. > > = Problem 1 - VM manager needs to parse qemu config = > > Your proposal implies: > > - VM manager supplies a basic configuration to qemu > > - It then immediately asks qemu for a dump of the machine > configuration in all its glorious detail and retains that > config > > - If the VM manager wishes to add a new device it needs to parse the > qemu config and add it, rather than just generate an entirely new > config > What's the problem with parsing the device config and modifying it? Is it just complexity? If we provided a mechanism to simplify manipulating a device config, would that eliminate the concern here? Regards, Anthony Liguori _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/virtualization