Re: UFS and Digital CDs

Francois-Rene Rideau (I+fare+WANT@tunes.NO.org.SPAM)
03 Sep 1998 14:32:51 +0200


macro@ds2.pg.gda.pl (Maciej W. Rozycki) writes:
>> On Wed, Sep 02, 1998 at 09:31:14PM -0400, Steven N. Hirsch wrote:
>>> 1) Place DEC distribution CD in drive.
>>> 2) Type:
>>> # mount -t ufs /dev/hda /mnt
>>>
>>> and... she's dead Jim.
>>>
>>> Instantaneous full kernel lock-up. 100% repeatable on any machine with
>>> any type (IDE or SCSI) of drive. No error messages, no log messages.
Thanks for reporting, but this has already been reported, and fixed,
as far as lock-up is concerned (the CD still can't be mounted, tho).

>>> Who would be the person to look into this little show-stopper?
>>>
> The problem lies in the UFS code. See a temporary patch at
> 'http://www.tunes.org/~fare/files/bu-2.1.117.patch.gz' which does not make
> UFS work but at least prevents it from halting the kernel.
Correct, except that since my pnatch evolves a bit with time
(and kernel releases), the address has changed. Point your browser to:
http://www.tunes.org/~fare/files/linux-ufs/
Currently, a patch for 2.1.119 is available (submitted to Linus already,
no ACK -- am I missing something, like a special address to submit patches?
And what about submitting to vger?).

> I believe Francois-Rene Rideau <fare@tunes.org> will be happy to see any
> corrections.

I sure will be happy to see them. However, I won't be writing them,
as I'm no more an active UFS developer (or user, even).
SO, if you really do need to read that CD, your options are
1) fix the driver (hints given in patch). I believe our friend
"Albert D. Cahalan" <acahalan@cs.uml.edu> has info about DEC UFS,
for whoever's ready to code support for them. Or you may "just" disable
cylinder groups when the partition is mounted read-only.
OR
2) use the old read-only driver, which can handle DEC CDs (at least, it could
when mounted thru the loop driver -- man losetup). Grab it from kernel 2.1.111
(files fs/ufs/* include/linux/ufs*). Then be sure to add a NULL entry
for the new flush method of various vfs ops tables.

Good luck, and happy kernel hacking!

## Faré | VN: Уng-Vû Bân | Join the TUNES project! http://www.tunes.org/ ##
## FR: François-René Rideau | TUNES is a Useful, Not Expedient System ##
## Reflection&Cybernethics | Project for a Free Reflective Computing System ##
I agree to pay for the *opportunity* to read a book or use a program;
I do not agree to pay for the *right* to do so.

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.altern.org/andrebalsa/doc/lkml-faq.html