Re: Difficulty playing DVDs under AHCI/CAM?

on 01/09/2010 21:21 Garrett Wollman said the following:
> <<On Wed, 01 Sep 2010 19:16:03 +0300, Andriy Gapon <avg_at_icyb.net.ua> said:
> 
>> Just want to draw attention of those who use ahci, have hald running and burn
>> optical media to couple of known issues:
> 
> What about those of us who use ahci, don't have hald running, and just
> want to read their DVDs?

I am not aware of any known but not resolved issues in this context.
But I think that I gave you a good advice.

> I never heard any response from you when I
> asked for a more specific debugging procedure.

Sorry about that, forgot to tell you about google.
Now, apologies about the joke, no offense meant :-)
These links should give a good overview for the start:
http://wiki.freebsd.org/DTrace
http://wiki.freebsd.org/DTrace/Examples
http://www.freebsd.org/doc/handbook/dtrace.html
http://wikis.sun.com/display/DTrace/Documentation

And, oh, here is a script that I used to investigate a somewhat similar problem
with failing ioctl.  I think you should be able to easily adapt it to your needs.

syscall::ioctl:entry
/execname == "k3b" && arg1 == 3299349762/
{
        self->trace = 1;
}

fbt:::entry
/self->trace/
{
}

fbt:::return
/self->trace/
{
        printf("%d", arg1);
}

syscall::ioctl:return
{
        self->trace = 0;
}

> My next step was going
> to be enabling CAMDEBUG and trying to find out which specific
> operation was failing, but I'm not a SCSI expert by any means....

Not sure if debugging with CAMDEBUG would be easier or not.
There could be lots of output.

-- 
Andriy Gapon