DVD/CD reading issues with -CURRENT from 2004-06-27

[Kevin Oberman]

> Date: Mon, 12 Jul 2004 15:36:26 +0800
> From: Ariff Abdullah <skywizard at MyBSD.org.my>
> 
> On Sun, 11 Jul 2004 22:12:44 -0700
> "Kevin Oberman" <oberman at es.net> wrote:
> 
> > > From: Justin Hibbits <jrh29 at po.cwru.edu>
> > > Date: Sat, 10 Jul 2004 20:05:15 -0400
> > > Sender: owner-freebsd-current at freebsd.org
> > > 
> > > Hi,
> > > 
> > > I updated to -CURRENT a couple weeks ago, for various reasons, from 
> > > 5.2.1, but now DVD and CD reading is flaking out.  When trying to
> > > play DVDs with mplayer, they stop after a random amount of time,
> > > probably after reading a complete buffer.  With 'dd', trying to
> > > create iso images of CDs, it stops after a random amount of data is
> > > copied.  Attached is the backtrace of a 'dd' run.
> > > 
> > > Specs of the system:
> > > 
> > > 5.2-CURRENT as of 2004-06-27
> > > Athlon XP 1800+
> > > ASUS A7V266-E/A motherboard (VIA KT-266 chipset)
> > > 
> > > The 2 drives I tested are:
> > > iomega Zip-CD CD-RW drive (acd0)
> > > Toshiba DVD-ROM (acd1)
> > > 
> > > Any more info required, just ask.
> > > 
> > > Additional, I'm not on the list, so if you could CC me, that'd be 
> > > great, otherwise, I'll just check the archives.
> > 
> > I reported this a couple of weeks ago. I had not used the drive
> > heavily for a while, so I don't know exactly when the problem started.
> > I have discovered that accessing the drive again (another mplayer)
> > will release the drive. I suspect that an interrupt may be getting
> > lost, but I'm far from sure.
> >
> 
> My trick is, to include atapicam support in kernel and access the cdrom
> using /dev/cd0 instead of /dev/acd0 .
> 
> mplayer dvd://1 -dvd-device /dev/cd0 etc.

I'm afraid not. I was already running ATAPICAM and accessing /dev/cd0. I
don't think it's an ATAPICAM issue and, since ATAPICAM is shim between
SCSI and ATAPI, it is unlikely to fix a problem like this. It could
cause a problem, I suppose, but the only way I can see for it to fix a
low-level problem would be if a race condition was involved (which still
might be the case).
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634