patch to fix burncd bug

[George Hartzell]

Jaakko Heinonen writes:
 > 
 > Hi,
 > 
 > On 2009-01-09, George Hartzell wrote:
 > > I have a mac pro running 7.1-PRERELEASE system (not sure when I last
 > > updated it) on which burncd seems to successfully burn the data but
 > > then fails while fixating.
 > > 
 > > I applied the above patch by hand, with a little bit of fuzz, and now
 > > it fails to burn the data but fixating no longer bombs out. 
 > 
 > It can't see how it could be possible that the patch (correctly applied)
 > causes this. Are you sure that this is repeatable behavior and burning
 > always works with an unpatched kernel? Does dmesg show any error
 > messages after failed burn?

Hmmmm.

I upgraded the machine to 7.1-STABLE and now the patch applies
cleanly (using 'patch').

I still get the behaviour that I described above.

So I backed out the patch, rebuilt, and it turns out that I see the
same behaviour on the stock kernel.  "It didn't use to do that. (tm)"  

There's a line in dmesg that says:

 acd0: TIMEOUT - WRITE_BIG retrying (1 retry left)

I have a feeling I've seen a thread about cd drives and BIG, but I
can't find it online or in the PR's.  I see some recent discussion or
READ_BIG, but no conclusion.

This is with the stock DVD drive in a Mac PRO, dmesg reports it to be

  acd0: DVDR <PIONEER DD-RW DR-112D/BC14> at ata2-master UDMA66

g.