This problem appears at any time during normal operation.
As you can see I have a CD-ROM.
If the ide cable is unplugged from the CD-ROM (on hdc) the problem never 
seems to happen.
If the ide cable is plugged into the CD-ROM (on hdc), the problem 
happens quite often, even it I never use the CD-ROM.

This is with kernel.org kernel 2.6.0-test1 without any patches.
If I use kernel 2.4.21, I have not seen these problems, but I have other 
problems with 2.4.21 so I cannot use it. E.g. In kernel 2.4.21, the NIC 
card does not receive any IRQs so therefore does not work. The system is 
a Dell Dimension 2400.
I cannot use any ALT-SYSRQ-T to output any stack trace, although the 
ALT-SYSRQ-T outputs properly when the fault is not present, i.e. before 
it hangs.

Has anyone seen this problem? The searches I did, did not result in any 
useful comments about my specific problem.
I am subscribed to linux-ide but not linux-kernel.

uname -a
Linux server 2.6.0-test1 #4 SMP Thu Jul 24 11:29:21 BST 2003 i686 GNU/Linux

Output to console screen, but not reaching log file: -

hda: dma_timer_expiry: dma status==0x20
hda: timeout waiting for DMA
hda: timeout waiting for DMA
hda: (__ide_dma_test_irq) called while not waiting
hda: status timeout: status=0x80 {busy}

/* Then a slight delay */
hda: drive not ready for command

ide0: reset: success
/* Then a slight delay */
hda: dma_timer_expiry: dma status==0x21
hda: timeout waiting for DMA
hda: timeout waiting for DMA
hda: (__ide_dma_test_irq) called while not waiting
hda: status timeout: status=0x80 {busy}

Details of ide setup from kern.log: -
Jul 23 16:40:48 server kernel: Uniform Multi-Platform E-IDE driver 
Revision: 7.00alpha2
Jul 23 16:40:48 server kernel: ide: Assuming 33MHz system bus speed for 
PIO modes; override with ide
bus=xx
Jul 23 16:40:48 server kernel: ICH4: IDE controller at PCI slot 0000:00:1f.1
Jul 23 16:40:48 server kernel: ICH4: chipset revision 1
Jul 23 16:40:48 server kernel: ICH4: not 100%% native mode: will probe 
irqs later
Jul 23 16:40:48 server kernel:     ide0: BM-DMA at 0xffa0-0xffa7, BIOS 
settings: hda:DMA, hdb:pio
Jul 23 16:40:48 server kernel:     ide1: BM-DMA at 0xffa8-0xffaf, BIOS 
settings: hdc:DMA, hdd:pio
Jul 23 16:40:48 server kernel: hda: ST3120026A, ATA DISK drive
Jul 23 16:40:48 server kernel: ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
Jul 23 16:40:48 server kernel: hdc: HL-DT-ST GCE-8481B, ATAPI CD/DVD-ROM 
drive
Jul 23 16:40:48 server kernel: ide1 at 0x170-0x177,0x376 on irq 15
Jul 23 16:40:48 server kernel: hda: max request size: 1024KiB
Jul 23 16:40:48 server kernel: hda: host protected area => 1
Jul 23 16:40:48 server kernel: hda: 234375000 sectors (120000 MB) 
w/8192KiB Cache, CHS=14589/255/63,
  UDMA(100)
Jul 23 16:40:48 server kernel:  hda: hda1 hda2 hda3 < hda5 hda6 hda7 >


Attached is output from "lspci -v"