On 14/05/2015 11:36, Michael S. Tsirkin wrote: > > There are three answers: > 1. Yes, it's sure to get detected because everything gets shifted > and then you get an unexpected string instead of next device name. > 2. If you want a more generic way to detect this, then please work > on changing format for devices generally so each device > section has a byte length attached to it. Then we know that > when we make changes, they are detected as device will end > earlier/later than expected.
No need for that. Subsections were introduced exactly to allow a change to be compatible in the common case and incompatible in the uncommon case. Check out "git log -- grep subsection -- savevm.c". > 3. You can have a different workaround: add property "skip config vec > on migration" and set it for old spapr machine types. > old types continue losing config vec; new ones work better. Why in the world would you want that? Paolo
