> If I have a chance later on, I can try reformatting the scratch drive with
> smaller and smaller partitions to see if there is a boundary point below
> which mount_ntfs works fine, but above which it fails.  This might give a
> clue as to where to look for the problem.  (Or it might not, if MS simply
> decided arbitrarily to format smaller disks using NTFS4 and larger ones
> using NTFS5...)

Okay, I did some further testing, and it looks like the boundary point is
around 512MB.  I was able to successfully mount a 500MB NTFS partition, but
a 520MB partition would not mount, with the usual errors:

  e:  1064385       63       NTFS                        # (Cyl.    0*- 1055)
[7] root@jdarrowp5:ttyp2:/var:# mount -t ntfs -o ro /dev/wd1e /mnt
mount_ntfs: /dev/wd1e on /mnt: Argument list too long
ntfs_readntvattr_plain: POSSIBLE RUN ERROR
ntfs_readattr_plain: ntfs_readntvattr_plain failed: o: 0, s: 66528
ntfs_readattr_plain: attrib: 0 - 64

Once again, I've made images available (though this time partial) through
ftp, at ftp://ftp.wheaton.edu/pub/jdarrow/

wd1.head.500m.gz : first 1MB of the disk when it has the mountable 500MB
   partition
wd1.head.520m.gz : first 1MB of the disk when it has the unmountable 520MB
   partition
wd1.tail.500m.gz : the 40MB approximately centering on the tail end of the
   500MB partition (starting at offset 480MB)
wd1.tail.520m.gz : the 40MB approximately centering on the tail end of the
   520MB partition (starting at offset 500MB)

(note that I did not rezero the disk between partitionings, as that would
have required an additional reboot into netbsd plus the time taken to do
the zeroing, so the 520MB tail image may contain remnants from the 500MB
tail image near the beginning...)

Hopefully this will help in tracking down the problem.  I can build and
test patched kernels and mount binaries, but would prefer they stay 1.5
branch-based if possible, as I make frequent use of union mounts, which
are known to have some trouble with UBC (at the moment).

jdarrow

-- 
John Darrow - Senior Technical Specialist               Office: 630/752-5201
Computing Services, Wheaton College, Wheaton, IL 60187  Fax:    630/752-5968
Alphapage: 6303160707@alphapage.airtouch.com            Pager:  630/316-0707
Email:     John.P.Darrow@wheaton.edu