bug#24448: Interpretation of partition entry sizes on "4kn" disks

In partition tables, GPT entries specifically, there are 8 byte fields for
the first and last LBA of the partition. Traditionally logical blocks are
512 bytes, but some new disks report sector sizes of up to 4096 bytes as
both logical and physical sector size.  For these so-called 4kn disks,
should the partition table entries be interpreted as representing units of
4096 bytes, or does the magic number 512 still apply to their partition
table entries?

I have been having a hard time determining which would be the expected
interpretation.

Thanks much,
Cris