Re: WD_QUIRK_FORCE_LBA48

[Manuel Bouyer <bouyer%antioche.eu.org@localhost>]

On Mon, Dec 07, 2009 at 01:34:18PM -0500, der Mouse wrote:
> >> Even that much could be avoided by the "cap at 128G and fall back to
> >> non-LBA48 on error", unless there exist interfaces which react to
> >> LBA48 accesses with neither correct LBA48 operation nor an easily
> >> detectible and retryable error.  Er, unless such interfaces exist
> >> and are common enough to care about - we can't work around _all_
> >> broken hardware.
> > It's not broken.  These controllers were designed before LBA48 was
> > specified.
> 
> Sure, it's not broken for them to fail to provide LBA48 operation.
> 
> But, depending on exactly how LBA48 works, it might be fair to call
> them broken if they don't produce an easily detectible error.  (I don't
> know much about LBA48, but I'd tend to assume it's something like the
> difference between 6-byte and 10-byte SCSI commands; if so, not
> producing an error does seem broken to me.)

Well, SCSI is sane in this respect. ATA is not, and full of hacks.
LBA48 is a hack to avoid adding extra registers addresses.

-- 
Manuel Bouyer <bouyer%antioche.eu.org@localhost>
     NetBSD: 26 ans d'experience feront toujours la difference
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