On Sun, Jun 14, 2015 at 08:06:22PM +0200, Michael S. Tsirkin wrote:
To summarise, you feel that modifying bus id without reordering bus ids between roots is likely, modifications that would cause reordering are unlikely, thus counting bus ids in order gives a stable index. Is that right?
Yes.
To be on the safe side, it would be nice to have bios skip some fields/properties when parsing paths, so that if we want to use another id in the future, we can supply both id types. I haven't looked at the parsing code - maybe it does this already?
SeaBIOS already does that. (SeaBIOS doesn't parse the bootorder file - it generates a "glob" like pattern for each device and then sees if that pattern matches a line in the bootorder file.)
Also, I don't have a strong objection to Laszlo's SeaBIOS patch (the one that does the runningOnQEMU() check). (I still think it's quirky to use bus-id in the file, but it's not a show stopper if it's just for QEMU.)
-Kevin