Re: debian-hppa install notes with some CD trouble
Meelis Roos wrote:
> The only CD-related errors in dmesg are in the form of not being able to
> read past end of device:
> [ 35.918389] sr 0:0:6:0: [sr0] tag#46 Sense Key : 0x3 [current]
> [ 35.973370] sr 0:0:6:0: [sr0] tag#46 ASC=0x6 ASCQ=0x0
> [ 36.019042] sr 0:0:6:0: [sr0] tag#46 CDB: opcode=0x28 28 00 00 01 9c 2c 00 00 02 00
> track:lout lba: 105518 ( 422072) 23:28:68 adr: 1 control: 4 mode: -1
This is probably the CD-TAO-Read-Ahead bug.
It can be avoided by burning the CD with write type SAO (wodim option -sao).
Most CD drives report the media size including the two TAO Run-Out blocks,
which are not readable by SCSI command 28h READ(10). This is due to an
ambiguity of SCSI/MMC specs for command 25h READ CAPACITY which only some
few drives interpret like Linux expects.
See my futile attempt to bring it to the attention of linux-scsi
The remedy would be reading the last two blocks always separately from
previous blocks and to interpret their failure as End-Of-Medium if they are
not ASC 0x11 (read error) or ASC 0x15 (positioning error). No reliable
prediction of the readability of these sectors seems possible.
(I could need contact to a kernel developer for this and some other
- Concurrent burn slowdown
- Failure to wait for loaded tray to become ready
- ioctl(BLKRRPART) refusing to re-assess CD/DVD/BD size after burning
- undocumented old SCSI command feature used to determine start of last
Have a nice day :)