Re: 2.9test9-mm1 and DAO ATAPI cd-burning corrupt

From: Prakash K. Cheemplavam
Date: Thu Nov 06 2003 - 16:39:14 EST


Prakash K. Cheemplavam wrote:
bill davidsen wrote:

In article <3FA8CA87.2070201@xxxxxx>,
Prakash K. Cheemplavam <prakashkc@xxxxxx> wrote:

| Sorry, I wasn't precise: The data is on the disc, as my DVD-ROM restores | the full image (md5sum matches), but the CD-RW does not.

There is a problem with ide-scsi in 2.6, and rather than fix it someone
came up with a patch to cdrecord to allow that application to work

b) The writing or reading issue mentioned above. It is a bit hard to find out, whether cdrecord actually *writes* an incomplete image (without using -pad), ie. throwing away the last 4096 bytes, which *only* happens in non-TAO mode. The programme CDRDAO shows the same behaviour. Strange enough reading this DAO written image out with my DVD-ROM makes this (missing?) 4096 bytes reappear... Well, maybe I should patch the image and put some other bytes instead of the 00s at the end to see, whether it is a write issue, a read issue of the writer or a read issue of the reader. Anyway, it doesn't sound right to me, what is happening at the moment...

So tested further: I patched the very last byts of the image and these are my findings:

In DAO mode, the complete image is actually written, but the writer is not able to read it out! The last 4096 bytes are not read. I put the CD-RW into my DVD-ROM, and it reads it out completely.

So: Is cdrecord/cdrdao making something wrong (yes, I know I can use -pad, but I want an *identical copy*) or has the kernel ATAPI reading routine a bug? (Or has my drive a bug???? Well, I need to read the disc out in windows I guess...)

Prakash

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/