no /dev/cdrom with 2.6.2 kernel

sohmc · 02-21-2004, 09:51 AM

I'm having problems getting my CD-RW/DVD drive to work correctly in 2.6.2

I've loaded the correct modules, I think, I'm unable to mount the drive. There is no /dev/cdrom. When I do an lsmod, it looks like the modules are installed.

I have a IDE CD-RW/DVD combo drive. It works correctly in 2.4.22 (with ide-scsi). Here is the lsmod for 2.6.2:

Code:

Module                  Size  Used by
snd_pcm_oss            47908  0 
snd_mixer_oss          17024  2 snd_pcm_oss
nfs                   151996  1 
lockd                  57288  2 nfs
sunrpc                116936  5 nfs,lockd
snd_seq_midi            7072  0 
snd_emu10k1_synth       7168  0 
snd_emux_synth         33792  1 snd_emu10k1_synth
snd_seq_virmidi         6272  1 snd_emux_synth
snd_seq_midi_event      6656  2 snd_seq_midi,snd_seq_virmidi
snd_seq_midi_emul       7296  1 snd_emux_synth
snd_seq                51984  5 snd_seq_midi,snd_emux_synth,snd_seq_virmidi,snd_
seq_midi_event,snd_seq_midi_emul
snd_emu10k1            89348  2 snd_emu10k1_synth
snd_rawmidi            20256  3 snd_seq_midi,snd_seq_virmidi,snd_emu10k1
snd_pcm                84768  2 snd_pcm_oss,snd_emu10k1
snd_timer              21380  2 snd_seq,snd_pcm
snd_seq_device          6920  6 snd_seq_midi,snd_emu10k1_synth,snd_emux_synth,sn
d_seq,snd_emu10k1,snd_rawmidi
snd_ac97_codec         51204  1 snd_emu10k1
snd_page_alloc          9476  2 snd_emu10k1,snd_pcm
snd_util_mem            3840  2 snd_emux_synth,snd_emu10k1
snd_hwdep               7712  1 snd_emu10k1
snd                    43364  15 snd_pcm_oss,snd_mixer_oss,snd_seq_midi,snd_emux
_synth,snd_seq_virmidi,snd_seq_midi_event,snd_seq,snd_emu10k1,snd_rawmidi,snd_pc
m,snd_timer,snd_seq_device,snd_ac97_codec,snd_util_mem,snd_hwdep
soundcore               7648  2 snd
lp                     10152  0 
autofs                 14592  0 
af_packet              17544  2 
e100                   58760  0 
ohci1394               31876  0 
ieee1394               67888  1 ohci1394
sg                     33176  0 
parport_pc             24232  1 
usblp                  11648  0 
floppy                 54132  0 
usb_storage            63168  0 
hid                    30528  0 
uhci_hcd               29584  0 
usbcore                94940  6 usblp,usb_storage,hid,uhci_hcd
thermal                11536  0 
processor              12336  1 thermal
unix                   23600  102 
ide_cd                 37764  0
sr_mod                 13860  0 
cdrom                  36000  2 ide_cd,sr_mod

Is there a special way that I need to configure this kernel? I know that 2.6 moved away from ide-scsi for cd-rw's but that doesn't explain why it won't recignize the drive on boot.

any thoughts?

Sideshow Bob · 02-21-2004, 04:04 PM

I am really new to linux, so I cannot give too much detail. I have the same problem and found an earlier posting with a possible solution. Kernel 2.6.x no longer uses scsi emulation for the cd drive. The solution was to remove scsi emulation from the kernel and change the bootloader from "hdn=ide-scsi" to "hdn=ide-cd" or possibly to "hdn=ide-cdrom". I checked make menuconfig to see if I could remove scsi emulation there, but no luck. If you know how to do it, please let me know. Hope it works.

sohmc · 02-21-2004, 04:18 PM

actually, I ended up fixing the problem. I had to recompile with IDE-CD as a module and disable ide-scsi. I also changed the kernel option to hdX=ide-cd

You *technically* don't need to remove ide-scsi if it's compiled as a module.

Try rmmod ide-scsi and then modprobe ide-cd.

When you change the kernel options, it should load ide-cd because you specified it.

Hope this helps.

sohmc · 02-21-2004, 04:18 PM

oh, as an FYI, in 2.6, ide-scsi is specified in the ATA/IDE section of "Device Drivers"

Sideshow Bob · 02-21-2004, 05:45 PM

Yep, it worked. Thanks for the info. One down, two to go.