My CD/DVD drive is not showing any more. The physical drive is okay; for testing, i'm running knoppix off a CD in this drive right now.

The machine normally runs Ubuntu 7.04 with kernel 2.6.17-12-386. I should have /dev/cdrom symlink to /dev/hdc, but hdc is missing. The drive is identified as LTN486S, found by the kernel but followed by "ERROR, PORTS ALREADY IN USE" and other suspicious claims. The relevant snippet of dmesg is below. The main hard drive hda, containing / and /home, works fine, though suspicious statements are made about ide0 too. There are no other ide devices. I vaguely suspect some sorta kernel module problem.

In trying various potential solutions, it's possible i screwed up something; make no assumptions! Several people in various linux/ubuntu forums have the similar problems, but i have found no solution yet. Any good ideas for further diagnostics?


[ 46.138383] md: raid6 personality registered for level 6
[ 46.141565] ICH4: IDE controller at PCI slot 0000:00:1f.1
[ 46.141640] ICH4: chipset revision 2
[ 46.141687] ICH4: not 100% native mode: will probe irqs later
[ 46.141746] ide0: BM-DMA at 0xfc00-0xfc07, BIOS settings: hdaMA, hdbio
[ 46.141882] ide1: BM-DMA at 0xfc08-0xfc0f, BIOS settings: hdcMA, hddio
[ 46.142013] Probing IDE interface ide0...
[ 46.189319] ieee1394: Initialized config rom entry `ip1394'
[ 46.204986] md: raid10 personality registered for level 10
[ 46.246664] ide0: I/O resource 0x3F6-0x3F6 not free.
[ 46.246719] ide0: ports already in use, skipping probe
[ 46.246769] Probing IDE interface ide1...
[ 46.255735] usb 1-1: new low speed USB device using uhci_hcd and address 2
[ 46.430156] hda: ST340015A, ATA DISK drive
[ 46.433268] usb 1-1: configuration #1 chosen from 1 choice
[ 46.685758] usb 2-1: new full speed USB device using uhci_hcd and address 2
[ 46.870782] usb 2-1: configuration #1 chosen from 1 choice
[ 46.981653] hdc: LTN486S, ATAPI CD/DVD-ROM drive
[ 47.101672] ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
[ 47.102068] ide1: I/O resource 0x376-0x376 not free.
[ 47.102122] hdc: ERROR, PORTS ALREADY IN USE
[ 47.102183] ide1 at 0x170-0x177,0x376 on irq 15
[ 47.102350] PCI: Setting latency timer of device 0000:00:1d.7 to 64
[ 47.102355] ehci_hcd 0000:00:1d.7: EHCI Host Controller
[ 47.102687] ehci_hcd 0000:00:1d.7: new USB bus registered, assigne

for comparison, here is a snippet containing the interesting part of dmesg when i boot up knoppix: the CD works, /dev/hdc appears.

FDC 0 is a post-1991 82077
RAMDISK driver initialized: 16 RAM disks of 100000K size 1024 blocksize
Uniform Multi-Platform E-IDE driver Revision: 7.00alpha2
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
ICH4: IDE controller at PCI slot 0000:00:1f.1
ACPI: PCI Interrupt Link [LNKC] enabled at IRQ 5
PCI: setting IRQ 5 as level-triggered
ACPI: PCI Interrupt 0000:00:1f.1[A] -> Link [LNKC] -> GSI 5 (level, low) -> IRQ 5
ICH4: chipset revision 2
ICH4: not 100% native mode: will probe irqs later
ide0: BM-DMA at 0xfc00-0xfc07, BIOS settings: hdaMA, hdbio
ide1: BM-DMA at 0xfc08-0xfc0f, BIOS settings: hdcMA, hddio
Probing IDE interface ide0...
hda: ST340015A, ATA DISK drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Probing IDE interface ide1...
hdc: LTN486S, ATAPI CD/DVD-ROM drive
ide1 at 0x170-0x177,0x376 on irq 15
Probing IDE interface ide2...
Probing IDE interface ide3...
Probing IDE interface ide4...
Probing IDE interface ide5...
hda: max request size: 128KiB
hda: 78165360 sectors (40020 MB) w/2048KiB Cache, CHS=65535/16/63
hda: cache flushes supported
hda: hda1 hda2 hda3 hda4
hdc: ATAPI 48X CD-ROM drive, 120kB Cache
Uniform CD-ROM driver Revision: 3.20
libata version 1.11 loaded.
mice: PS/2 mouse device common for all mice
EISA: Probing bus 0 at eisa.0
EISA: Detected 0 cards.
NET: Registered protocol family 2