Re: Testers for OpenBSD & NetBSD needed
On Fri, Aug 20, 2004 at 03:18:52AM +0200, Frederick Page wrote:
> Hi Joerg,
> Joerg Schilling wrote on Fri, Aug 20 2004:
> >>> Aug 19 18:39:45 thebetteros /bsd: cd0: transfer error, downgrading to
> >>> DMA mode 2
> >Your problem is caused by a OpenBSD kernel bug. The kernel does not
> >handle odd DMA counts for ATA correctly.
> Are you sure it's a kernel-bug? (Please see below).
> >If you install cdda2wav suid root and call it as non root user, does
> >it work?
> To my total astonishment: YES. After suid it also works as root!
> -r-sr-xr-x 1 root bin 261K Aug 19 18:18 /usr/local/bin/cdda2wav
> >In order to avoid the Kernel bug from preventing you to do the test,
> >check the number of tracks on the CD. It it was a CD with an even
> >number of tracks, use one with an odd number of tracks or vice versa.
> Did that a couple of times, but the number of tracks seems to be
> irrelevant. After suid'ing cdda2wav it works with each and every CD
> now, as root and as fpage.
> I'm totally confused about what might be going on here :-(
> Thanks for the hints, now I got a working cdda2wav on OpenBSD ;-)
Well, I have been using cdda2wav on OpenBSD for years ... and
I have been the cdrtools port maintainer for a good while now.
I've only seen such problems in two situations:
1) bad hardware: drive, cable, or IDE device (95%)
2) cd and hdd with heavy i/o on same IDE channel (5%)
Of course, you shouldn't be able to use /dev/rcd?c at all unless
either you're part of the operator group, or the programs that access
the drive are suid root or sgid operator, or you change permissions
on the device. I usually add my user to the operator group and
then chmod g+w /dev/rcd0c so I can also write to it.