Re: ide-cd.c, "MEDIUM_ERROR" handling

[Gunther Mayer <gunther.mayer@gmx.net>]

Zinx Verituse wrote:

> I recently bought a DVD drive which appears to not retry enough when it's
> having trouble reading a disc - I'm requesting an option (or changing the
> default behavior) so that this drive is actually usable with the Linux
> ide-cd drivers - specificly, the code:
> 	} else if (sense_key == MEDIUM_ERROR) {
> 		/* No point in re-trying a zillion times on a bad
> 		 * sector...  If we got here the error is not correctable */
> 		ide_dump_status (drive, "media error (bad sector)", stat);
> 		do_end_request = 1;
> 	}
> needs to be disabled for my drive to read CDs properly.
>
> With this code enabled, no retries are made, and the kernel sees medium errors
> and returns bad data to the application reading; 
It would be a kernel bug if it returns bad data. It should return an 
error code to the application.

- The device should implement a decent retry strategy.
- There are special forensic applications which can be tuned to re-read 
bad sectors multiple times if needed.
-
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