Subject: Re: kern/10430: Wd driver cannot handle bad144 table properly?
To: None <gnats-bugs@gnats.netbsd.org, netbsd-bugs@netbsd.org>
From: Greg A. Woods <woods@weird.com>
List: netbsd-bugs
Date: 06/24/2000 13:59:09
[ On Saturday, June 24, 2000 at 07:01:01 (+0900), Takahiro Kambe wrote: ]
> Subject: Re: kern/10430: Wd driver cannot handle bad144 table properly?
>
> But bad144 is still useful when one bad sector was created by sudden
> poewr failure, in my little experience.

I'm not sure I understand how this can be.

If the sector has been damaged in such a way that it can no longer be
written to then it should be automatically reallocated by the drive when
it fails to verify after being written to (perhaps after several
retries).

I'm not sure what happens with the 'wd' drives these days but on SCSI
drives one often has to turn on the AWRE (and ARRE) flags because
they're usually not on in the factory default configuration (nor do any
NetBSD SCSI drivers turn them on automatically so far as I know).
Perhaps there's a similar "feature" on 'wd' drives?

On the other hand if nothing's really wrong with the physical sector
then all you have to do is write the correct data back to it.
Allocating it as a "bad" sector is, it seems, counter-productive.

-- 
							Greg A. Woods

+1 416 218-0098      VE3TCP      <gwoods@acm.org>      <robohack!woods>
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