Re: partion code doesn't consider 2048 bytes sectors

Gerard Roudier (groudier@club-internet.fr)
Tue, 16 Sep 1997 22:39:54 +0200 (MET DST)


On Mon, 15 Sep 1997, Paul Slootman wrote:

> -=Magick=- <owner-linux-kernel@vger.rutgers.edu> wrote:
> >
> >I have a scsi MO-drive, and it uses a hardware sectorsize
> >of 2048 bytes. The partitions I make on a disk under dos/windoze
> >have a sectorsize of 2048 bytes. But under linux the partition
> >code assumes a sectorsize of 512 bytes.
>
> Are you sure the problem is in the partition code?
>
> I recently tried a SCSI disk formatted to 1K sectors. It looked
> like it worked (fdisk seemed to be OK), but accessing partitions
> after this failed with all sorts of horrifying errors. Before
> you say, "Aha, partitions!", when I replaced the NCR810 SCSI
> controller with an Adaptec 1542CF, it worked perfectly. I think
> it also works with my Buslogic card.
>
> So, I think there is some problem with the NCR810 code.
> You don't mention what SCSI adapter you're using?

To *think* is always allowed, but did you first *do* the following for
*each* controller and *each* possible secteur size?

1 - Fill the medium with all *zeros* (cat /dev/zero >/dev/sdX (replace X
by the driver letter).
2 - Partition the disk using *Linux*.
3 - Check if the geometry is coherent using *fdisk*.
4 - Check your SCSI bus and terminators.
5 - Run your tests.

Low-level drivers are not concerned by sector size. If the problem seems
to be due to the sector size, you should suspect another kernel module.

Gerard.