CD-ROM Crashing Mandrake 9.1
 

complete linux newbie, trying to make a MythTV / DVD Player / MP3 Player / Etc. for the house. No internet yet, moved out to the boonies and I can't seem to get up the energy to order dial-up =). Burned the three install discs at work and took them home with a 4th with MythTV and all the stuff I think I'll need (including all the PLF RPMs). Anyways...

A-Bit BH6 Mobo
Celeron 500
384 megs memory
GeForce 2 w/ TV out
Hauppauge PVR-250 TV Card
SoundBlaster 128PCI
some generic 10/100 network card
10 gig system drive
120 gig storage drive
52X Sony CD-ROM (until the DVD-ROM gets here)
Mandrake 9.1, formatted HD

The problem is in the CD-ROM, me thinks. Whenever I try to access it in GNOME or KDE the machine locks up (no mouse or anything). My instinct said 'DMA problems' so i removed the 120gig and put the 10gig on one IDE line and the CD-ROM on the other. Still no worky-worky. I know the drive is good because I've installed Man9.1 three times now from it.

Like I said, complete and utter linux newbie. The _only_ linux experience I have is shell accounts back in the day and maybe a couple weeks of admining an old machine like 8 years ago (it was old back then!). Can't say I miss 'man -k' much. So it's probably something small and stupid I'm missing.

Any thoughts? Thanks.

Does this only happen in Gnome and KDE?

What I mean is, have you tried using the command line to browse a CD? (ls -l /mnt/cdrom or something)

How about from another window manager (like blackbox)?

I would have said the same as you (DMA problem) but you did install Mdk 9.1 from that CD ROM right? I mean I'm not sure DMA problems would "kick in" only after that.

Also, are you using supermount? It works for me, but I know quite a few people with whom this has caused a lot of problems.

I haven't tried accessing it from the command line yet. Actually I did try, but I was trying /dev/cdrom in my newbie mind-set =). I will try the /mnt/ directory instead next time.

Yes, supermount is on. I did try changing the type from 'auto' to 'iso9886' but it didn't help. I'll try manually mounting the device. Do you have to mount and un-mount whenever the CD-ROM changes?

If you have supermount, you don't. That's what it does, mounts and unmounts removable drives for you.

If you disable supermount (I forget the command, but I'm sure if you google around you'll find it real easy) then yes, you have to mount and unmount your CDs before you read them.

This could be being caused by APIC being turned on in the BIOS. APIC (Advanced Programmable Interrupt Controller) is normally used with multiple CPUs and is known to cause problems with some motherboards with a single CPU. You can either turn it off in the BIOS, or add 'noapic' to the 'append=' line in /etc/lilo.conf so that it is turned off when Linux boots. For example, if the 'append=' line says:

append="quiet devfs=mount hdd=ide-scsi acpi=off"

then change it with a text editor, as root, to read:

append="quiet noapic devfs=mount hdd=ide-scsi acpi=off"

Then open a console as root and run the command:

lilo

which re-configures the bootloader according to the changes you made in /etc/lilo.conf. Once you re-boot the computer, APIC is turned off by the bootloader. It's possible that APIC could be causing your problem, so it's worth a try. You should also make sure that Plug n Play OS is disabled in the BIOS, so that hardware detection is performed correctly on bootup. Other Mandrake 9.1 installation tips here:

http://www.mandrake.tips.4.free.fr/install.html

I re-installed Mandrake with the main HD on one IDE and the CD-ROM on the other and got it working well. Installed some RPMS and started working on getting MythTV going. Then I turned the machine off and re-configured the drives to the way I had it initially. Now it's not working again.

Any access to the cdrom drive locks the computer completely. Accessing it from the command line locks it. Even just trying to install RPMs off of the Mandrake distro will lock the machine when it trys to access the CD-ROM.

How would I turn DMA off on an IDE channel or device?

I'll try the ACPI thing and get back to you with results.

Turning DMA off (as root):

hdparm -d0 /dev/hdx

where x=a, b, c, or d, according to:

hda = Primary IDE Master
hdb = Primary IDE Slave
hdc = Secondary IDE Master
hdd = Secondary IDE Slave

turning off ACPI didn't help, still locks. I've been playing with mount trying to see if I can get it to work manually, but so far it has locked every time I try to mount the CD-ROM. Reading the man and info on mount isn't sinking in yet, I'm not sure what 90% of the commands do, could be working it wrong.

I'll try the DMA trick and see if I can get it to work. Thanks.

It worked, my CD-ROM works fine now. But it doesn't stick, I need to run this command every time I boot. How do I make it perminent? Thanks.

Put that command as a separate line at the end of /etc/rc.d/rc.local. That will ensure it is activated each time on boot.