In <199912101623.IAA12956@jericho.one-o.com>
eeh@one-o.com wrote:

> Both ffs and swap code know about the disklabel and bootblocks and
> skip over the first 8K of the partition, so you can use a partition
> that starts at sector 0 for a filesystem or swapping without damaging
> the label.  Other filesystems may not be so obliging.

/sys/uvm/uvm_swap.c:swapon() seems to skip only the first PAGE_SIZE
of the partition, not 8Kbytes.
---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp