Re: [usb-storage] [Merging ATA passthru] on integrating SMART/ATA-Security in usb-storage driver

James Bottomley
2005-11-04T20:49:55Z

On Fri, 2005-11-04 at 12:30 -0800, Matthew Dharm wrote:
> > What happens if you prevent USB mangling the scsi_level? I think, for
> > the most part, we would handle 0 in about the same way as we handle 2.
> > However, we could gate the if around the CDB[1] mangling as
> >
> > if (scsi_level != SCSI_UNKNOWN && scsi_level <= SCSI_2)
> >
> > which should fix your problem, I think.
>
> A long time ago, usb-storage didn't mangle the scsi_level. And almost
> nothing worked. Without a SCSI level, 6-byte commands get sent; only
> 10-byte commands will do.

That area of the scsi subsystem has been changed significantly ...
mainly for usb storage. I don't believe your assertion about
SCSI_UNKOWN only producing 6 byte CDBs to be correct, the behaviour is
now governed by two scsi_device flags: use_10_for_rw and use_10_for_ms
which you can control in slave configure.

Can you just try it with a modern kernel and see if anything still
breaks?

Thanks,

James