Devices not supporting read-6....

[Gerard Roudier]

T10/990D (SBC) rev. 8b, 8 July 1997.
excerpt from 6.1.4 speaking about READ(6) 

" this command has been maintained as mandatory since some system
  initialization routines require that the READ(6) command be 
  used. Application clients should migrate from the READ(6) command 
  to the READ(10) command ....... "

This let me think like OSes and pass-through applications are suggested
since a long time to no longer use READ(6), even with devices that are
still required to implement it.

On Fri, 21 Jan 2000, Rogier Wolff wrote:
 
> Hi,
> 
> As far as I know, "read-6" is a very mandatory command. However
> there is a device, the 
> 
>    {"TOSHIBA","DVD-RAM SD-W1101","*", BLIST_GHOST},

The MMC specs does not tell about READ(6) being mandatory (assuming the
device model is that one).

> which doesn't implement it.
>
> What do we do? 
> 
> 	- Blacklist it as "doesn't support read-6" and implement
>           stuff to prevent read-6 if that flag is set?
> 
> 	- Ignore the issue, and just let people with this hardware
> 	  live with a non-working drive?

We should not use READ(6) at all in our current SCSI stuff.
I remember having posted about that years ago.
 
> Is there maybe already something implemented? Anybody the "owner" of
> that piece of code?
> 
> I seem to own the "blist_ghost" stuff, so it's going to be listed
> there, but then the system runs into not-working read-6 commands.

Using READ(6) is irrelevant since years. I do think it is severe bug 
to still use READ(6) as default read command in current SCSI access
methods.

  Gérard.

PS: people that have old devices that donnot implement READ(6) should 
    upgrade their hardware or use old softwares, but not require softwares 
    to support everything that has ever existed. 

 				Roger.
> 
> P.S. (I'm not on linux-scsi, and I'm on vacation starting saturday).
> I had been hoping it would've been as easy as listing the drive as
> a 'blist_ghost' thing, but now things are more complicated... 
> 
> 
> -- 
> ** R.E.Wolff en BitWizard.nl ** http://www.BitWizard.nl/ ** +31-15-2137555 **
> *-- BitWizard writes Linux device drivers for any device you may have! --*
>  "I didn't say it was your fault. I said I was going to blame it on you."


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