Re: ide-cd doesn't replace ide-scsi?

[Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>]

On 11/28/05, Bill Davidsen <davidsen@tmr.com> wrote:
> Luke-Jr wrote:
> > Note: results are with 2.6.13 (-gentoo-r4 + supermount) and 2.6.14 (-gentoo)
> > I've been struggling with burning DVD+R DL discs and upgrading the firmware on
> > my DVD burner, and just today decided to rmmod ide-cd and try using ide-scsi.
> > Turns out it works... so is ide-cd *supposed* to handle cases other than
> > simple reading and burning or is this a bug? If not a bug, should ide-scsi
> > really be marked as deprecated?
> > Also, two bugs with ide-scsi:
> > 1. On loading the module, it detects and allocates 6 SCSI devices for a single
> > DVD burner (Toshiba ODD-DVD SD-R5272); kernel log for this event attached
> > 2. On attempted unloading of the module, rmmod says 'Killed' and the module
> > stays put, corrupt. There was some kind of error in dmesg, but it appears to
> > have avoided syslog-- If I see it again, I'll save it.
>
> I think you may have the probe-all-LUNs set, and a CD burner which
> responds to more than one. That's one possible cause for this.

That may be it.

> Unfortunately using ide-cd still doesn't have the code set to allow all
> burning features to work if you are not root. Even if you have
> read+write there's one command you need to do multi-session which is
> only allowed to root. Works fine for single sessions, I guess that's all
> someone uses.

Interesting because both drivers ide-cd and sr+ide-scsi use exactly
the same code (block/scsi_ioctl.c) to verify which commands don't
need root privileges.  Care to give details?

> Haven't tried unloading the module, so I have no advice on that other
> than "don't do that."

Known problem with ide-scsi, reference counting for "virtual" SCSI host
is missing (it was always buggy but was exposed in 2.6.x something by
sr.c changes).

Bartlomiej