Re: Problem with libata-pata, ATAPI DVD reader and a"copy-protected" audio cd

From: GhePeU
Date: Thu Mar 08 2007 - 08:36:31 EST


Il giorno sab, 03/03/2007 alle 12.00 +0100, GhePeU ha scritto:
> Hello,
>
> when kernel 2.6.20 was released I switched to the new libata-pata
> infrastructure for my EIDE hard disk and ATAPI dvd-reader.
>
> Until yesterday I didn't have any problem, then I tried to play an audio
> CD and my media player hanged. Looking to the logs, I found that the DVD
> reader (a Toshiba SD-M1612) was having problems reading the disk and
> that the kernel dropped its speed from UDMA/33 to PIO3 before I could
> eject the CD. Attached to this mail are the relevant lines of the system
> log.
>
> After a careful scrutiny of the box, I noticed that the disk was one of
> those "Copy protected" non-standard CD. With the old ide driver I could
> play and rip the CD without problems, so from a user point of view this
> is a regression.
>
> Besides, with the reduced speed the DVD reader was almost unusable, and
> since the new libata layer doesn't support forcing the driver speed with
> hdparm, I had to reboot the machine.
>
> So my questions are:
>
> 1) it is possible to implement a command to force re-detection of the
> better transfer mode available? I suppose that by unloading and
> reloading the module, the transfer mode should become again the better
> available, but when the driver is compiled in-kernel, this is not
> possible.
>
> 2) is there a way to access copy protected audio CD again? the only
> change here was ide -> libata, so there has to be some difference in the
> error handling of the two layer that caused this pseudo-regression.
>
> Thank you in advance
>
> Giacomo
>
> PS. I'm not subscribed to the list. I'm going to regularly check the
> archives in the next days to see if there are responses, CC me if you
> can. Thank you.
>
>

Well, it happened again, with a different cd, and this time I never
started the player: hal/g-v-m tried to access the CD and now my driver
is in PIO2 mode and pretty much unusable. Is there a way to fix this
without rebooting?

Giacomo

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