port-sparc64/53833: Booting sparc64 install ISO prints disklabel warnings

[gson%gson.org@localhost (Andreas Gustafsson)]

>Number:         53833
>Category:       port-sparc64
>Synopsis:       Booting sparc64 install ISO prints disklabel warnings
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    port-sparc64-maintainer
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Jan 04 18:15:00 +0000 2019
>Originator:     Andreas Gustafsson
>Release:        NetBSD-current, source date >= 2018.11.12.20.54.03
>Organization:

>Environment:
System: NetBSD
Architecture: sparc64
Machine: sparc64
>Description:

Booting a NetBSD-current/sparc64 install CD image in qemu prints some
warning messages about the cd0 disklabel:

  [   7.3040075] atapibus0 at atabus1: 2 targets
  [   7.3040075] cd0 at atapibus0 drive 0: <QEMU DVD-ROM, QM00003, 2.5+> cdrom removable
  [   7.3980303] WARNING: 1 error while detecting hardware; check system log.
  [   7.4320367] WARNING: cd0: total sector size in disklabel (640640) != the size of cd0 (160160)
  [   7.4320367] WARNING: cd0: end of partition `a' exceeds the size of cd0 (160160)
  [   7.4320367] WARNING: cd0: end of partition `f' exceeds the size of cd0 (160160)
  [   7.4449390] root on cd0a dumps on cd0b
  [   7.4566987] WARNING: cd0: total sector size in disklabel (640640) != the size of cd0 (160160)
  [   7.4566987] WARNING: cd0: end of partition `a' exceeds the size of cd0 (160160)
  [   7.4566987] WARNING: cd0: end of partition `f' exceeds the size of cd0 (160160)
  [   7.4869062] root file system type: cd9660

Since 640640 is exactly four times 160160, perhaps there is some kind
of confusion between 512 and 2048 byte sectors.

The warnings appeared with the commits:

   2018.11.12.20.54.03 jdolecek src/sys/dev/ic/mvsata.c 1.46
   2018.11.12.20.54.03 jdolecek src/sys/dev/scsipi/atapi_wdc.c 1.133

Before that, a different warning was printed instead:

  [   8.5335726] cd0: 25955248 trailing sectors not covered by disklabel

Installation succeeds despite the warnings.

>How-To-Repeat:

>Fix: