Re: WD_QUIRK_FORCE_LBA48

[der Mouse <mouse%Rodents-Montreal.ORG@localhost>]

>> I would not suggest doing this unless (a) the drive claims to be
>> LBA48-capable and (b) the drive claims to be at least 0x10000000
>> sectors long.
> Make that 0x10000001.  128Gb drives don't need LBA48 to access the
> last sector.

In theory, maybe.  As I remarked upthread, I own a drive which errors
on non-LBA48 accesses to sector 0xfffffff. (Admittedly, it's
substantially over 128G, but I see no reason a drive of exactly 128G
couldn't exhibit the same syndrome.)

> But then you'd break actually-working setups.

The only setups such a change would break would be those with >128G
drives onj non-LBA48 controllers but which do not actually access the
drive beyond the 128G mark.

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.

The "try it and see if it errors" approach could maybe also be used to
detect the "broken 0xfffffff" syndrome too....

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