When I started using UML with SystemImager, the partitioning with sfdisk
failed with the following message:
Warning: start=2 - this looks like a partition rather than
the entire disk. Using fdisk on it is probably meaningless.
[Use the --force option if you really want this]
I looked through the ubd code and found that it was always reporting 2
as the starting sector, instead of returning the actual value. The
attached patch returns the correct starting sector for the HDIO_GETGEO