Re: DVD/CD Read Problem: cdrom_decode_status: status=0x51 {DriveReady SeekComplete Error}

[Adam Kessel <adam@bostoncoop.net>]

On Sun, Jul 13, 2003 at 07:51:07PM +0400, Andrey Borzenkov wrote:
> this is ide-cd problem. drivers/ide/ide-cd:cdrom_decode_status():
> [ ... ]
>                } else if ((err & ~ABRT_ERR) != 0) {
> [ ... ]
>                } else if (sense_key == MEDIUM_ERROR) {
> [ ... ]
> they are not user-space issues. Try to swap two conditions above and see what 
> happens. I cannot test it anymore for reason below ...

Swapping these conditions improved the situation quite a lot.
Subjectively, I would say it's 90% better. By extending the read-ahead
cache to 32M, I can play the DVD almost perfectly with those conditions
(ABRT_ERR and MEDIUM_ERROR) swapped.  

Also, for the first time, I get messages of this sort in syslog:

Jul 13 22:22:47 joehill kernel: end_request: I/O error, dev hdc, sector 7865320
Jul 13 22:22:47 joehill kernel: Buffer I/O error on device hdc, logical block 983165

Before, the only sorts of errors I ever got were:

Jul 13 00:14:35 joehill kernel: hdc: cdrom_decode_status: status=0x51 { DriveReady SeekComplete Error }
Jul 13 00:14:35 joehill kernel: hdc: cdrom_decode_status: error=0x30LastFailedSense 0x03 
Jul 13 00:14:35 joehill kernel: hdc: ide_intr: huh? expected NULL handler on exit

Is there a reason these conditions should *not* be swapped? Is there
something I can test? Otherwise, my problem is basically fixed by this
change.

--Adam Kessel