[Coco] BUG with rbsuper and tc3 drivers SOLVED!

[Tormod Volden]

On Tue, Feb 14, 2017 at 8:00 PM, Tormod Volden wrote:
> dmode doesn't call the driver so that sounds strange. Can you please
> send these descriptors to me. At least dmode issues I can reproduce
> without having SCSI disks :)
>
> What remains unclear to me is whether the DRV field has to be unique
> per controller, for every target and partition. I get a vague
> impression of this after reading the SuperDriver manual, and I also
> see rbsuper use the DRV number for its cache matching logic.
>
> I wonder if reading a sector from target 4 just after writing to the
> same sector number to target 3 would return what was written to target
> 3, unless also the DRV numbers are different? Especially since rbsuper
> is unaware of DNS being used for target number. Or likewise reading
> from one partition after writing to the same logical sector on another
> partition, because although it is rbsuper that adds the partition
> offsets, it does so after checking for cache hit and only just before
> calling the low-level driver on cache miss.

Yup, see the Partitioning section on
http://nitros9.sourceforge.net/wiki/index.php/SuperDriver
"Do NOT allow two device descriptors share the same logical drive
number if they have different LSN offsets."

I guess the same applies for different SCSI target IDs, so we should
fix the stock descriptors to both have different DRV and DNS.

Tormod